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Recommendation and review posted by Bethany Smith
Woman’s genetic counselors can help you understand your genetic risks for certain diseases, such as cancer, or for passing an existing disease on to a child. Genetic counseling can lead to the earliest detection of diseases you or your baby may be at-risk of developing.
If you are concerned about diseases that run in your family, talk to you doctor about genetic counseling.
Genetics is the study of heredity, the process in which parents pass certaingenesonto their children. A person’s physical appearance height, hair color, skin color and eye color are determined by genes. Other characteristics affected by heredity include:
Humans have an estimated 100,000 different genes that contain specific genetic information, and these genes are located on stick-like structures in the nucleus of cells called chromosomes.
When a gene is abnormal, or when entire chromosomes are left off or duplicated, defects in the structure or function of the body’s organs or systems can occur. These mutations or abnormalities can result in disorders such as cystic fibrosis, a recessive genetic disease, or Down syndrome, an abnormality that occurs when a baby receives three No. 21 chromosomes.
Each person has more than 100,000 genes that direct the growth and development of every part of the body. These genes carry instructions for dominant or recessive traits that can be passed on to a child.
People who might be especially interested in genetic counseling for pregnancy include:
Women who might be especially interested in genetic testing regarding disease specific genes include:
Should it be necessary, Woman’s genetics team,which includes geneticist,Dr. Duane Superneau,can work with your oncologists and breast surgeons in determining a need forgenetic testing and your course of treatment.
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Genetic Counseling | Woman’s Hospital | Baton Rouge, LA
Recommendation and review posted by Bethany Smith
Presented at the 8th World Congress for Hair Research (2014) Jeju Island, South Korea.
Understanding molecular mechanisms for regeneration of hair follicles during wound healing provides new opportunities for developing treatments for hair loss and other skin disorders. We show that fibroblast growth factor 9 (fgf9) modulates hair follicle regeneration following wounding of adult mice. Inhibition of fgf9 during wound healing severely impedes this wound-induced hair follicle neogenesis (WIHN). Conversely, overexpression of fgf9 results in a 2-3 fold increase in the number of neogenic hair follicles. Remarkably, gamma-delta T cells in the wound dermis are the initial source of fgf9. Deletion of fgf9 gene in T cells in Lck-Cre;floxed fgf9 results in a marked reduction in WIHN. Similarly, mice lacking gamma-delta T cells demonstrate impaired follicular neogenesis.
We found that fgf9, secreted by gamma-delta T cells, initiates a regenerative response by triggering Wnt expression and subsequent Wnt activation in wound fibroblasts. Employing a unique feedback mechanism, activated fibroblasts then express fgf9, thus amplifying Wnt activity throughout the wound dermis during a critical phase of skin regeneration. Strikingly, humans lack a robust population of resident dermal gamma-delta T cells, potentially explaining their inability to regenerate hair.
These findings which highlight the essential relationship between the immune system and tissue regeneration, establish the importance of fgf9 in hair follicle regeneration and suggests its applicability for therapeutic use in humans.
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Dr George Cotsarelis: Hair Follicle Stem Cells & Skin …
Recommendation and review posted by Bethany Smith
Genetics is the branch of science that deals with how you inherit physical and behavioural characteristics including medical conditions.
Your genes are a set of instructions for the growth and development of every cell in your body. For example, they determine characteristics such as your blood group and the colour of your eyes and hair.
However, many characteristics aren’t due to genes alone environment also plays an important role. For example, children may inherit ‘tall genes’ from their parents, but if their diet doesn’t provide them with the necessary nutrients, they may not grow very tall.
Genes are packaged in bundles called chromosomes. In humans, each cell in the body contains 23 pairs of chromosomes 46 in total.
You inherit one of each pair of chromosomes from your mother and one from your father. This means there are two copies of every gene in each cell, with the exception of the sex chromosomes, X and Y.
The X and Y chromosomes determine the biological sex of a baby. Babies with a Y chromosome (XY) will be male, whereas those without a Y chromosome will be female (XX). This means that males only have one copy of each X chromosome gene, rather than two, and they have a few genes found only on the Y chromosome and play an important role in male development.
Occasionally, individuals inherit more than one sex chromosome. Females with three X chromosomes (XXX) and males with an extra Y (XYY) are normal, and most never know they have an extra chromosome. However, females with one X have a condition known as Turner syndrome, and males with an extra X have Klinefelter syndrome.
The whole set of genes is known as the genome. Humans have about 21,000 genes on their 23 chromosomes, so the human genome contains two copies of those 21,000 (except for those on X and Y in males).
Deoxyribonucleic acid (DNA) is the long molecule found inside chromosomes that stores genetic information. It is tightly coiled into a double helix shape, which looks like a twisted ladder.
Each ‘rung’ of the ladder is made up of a combination of four chemicals adenine, thymine, cytosine and guanine which are represented as the letters A, T, C and G.
These ‘letters’ are ordered in particular sequences within your genes and they contain the instructions to make a particular protein, in a particular cell, at a particular time. Proteins are complex chemicals that are the building blocks of the body. For example, keratin is the protein in hair and nails, while haemoglobin is the red protein in blood.
There arearound six billion letters of DNA code within each cell.
As well as determining characteristics such as eye and hair colour, your genes can also directly cause or increase your risk of a wide range of medical conditions.
Although not always the case, many of these conditions occur when a child inherits a specific altered (mutated) version of a particular gene from one or both of their parents.
Examples of conditions directly caused by genetic mutations include:
There are also many conditions that are not directly caused by genetic mutations, but can occur as the result of a combination of an inherited genetic susceptibility and environmental factors, such as a poor diet, smoking and a lack of exercise.
Read more about how genes are inherited.
Genetic testing can be used to find out whether you are carrying a particular genetic mutation that causes a medical condition.
This can be useful for a number of purposes, including diagnosing certain genetic conditions, predicting your likelihood of developing a certain condition and determining if any children you have are at risk of developing an inherited condition.
Testing usually involves taking a blood or tissue sample and analysing the DNA in your cells.
Genetic testing can also be carried to find out if a foetus is likely to be born with a certain genetic condition by extracting and testing a sample of cells from the womb.
Read more about genetic testing and counselling.
The Human Genome Project is an international scientific project that involves thousands of scientists around the world.
The initial project ran from 1990 to 2003. Its objective was to map the immense amount of genetic information found in every human cell.
As well as identifying specific human genes, the Human Genome Project has enabled scientists to gain a better understanding of how certain traits and characteristics are passed on from parents to children.
It has also led to a better understanding of the role of genetics in a number of genetic and inherited conditions.
Page last reviewed: 08/08/2014
Next review due: 08/08/2016
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Genetics – NHS Choices
Recommendation and review posted by Bethany Smith
Breast Cancer Research for Your Doubting Doctor Beautifully done research from Italy shows how progesterone protects against breast cancer and looks at the underlying causes of breast cancer.
Open Letter to Oprah about Bioidentical Hormones An open letter to Oprah about her show on bioidentical hormones.
Bioidentical (Natural) Hormones and Heart Disease Bioidentical (natural) hormones, used wisely, may lower heart disease risk in women.
The Wiley Protocol The Wiley Protocol involves mega-doses of hormones and menopausal menstruation.
Bioidentical (Natural) Hormones and Breast Cancer Bioidentical (natural) hormones, used wisely, do not increase the risk of breast cancer in women, and there is plenty of evidence-based science to back this up.
Dr. John Lee’s 3 Rules for BHRT A Dr. John Lee classic – clear, commonsense guidelines for when and how to use bioidentical hormone replacement therapy (BHRT), also called natural hormone replacement therapy (NHRT).
Progesterone Cream FAQs Dr. John Lee and Virginia Hopkins answer frequently asked questions about natural progesterone cream include: what is natural progesterone; how to use natural progesterone cream; what dosage to use; real progesterone vs. progestins; how safe is progesterone, and when to use progesterone cream.
How to Get Off HRT Questions and Answers from Dr. Lee and Virginia Hopkins about how to get off HRT and onto natural hormones, also known as bioidentical hormone therapy (BHRT). How to have balanced hormones, and relief from menopausal symptoms, without using conventional HRT.
HRT, Breast Cancer and the Women’s Health Initiative An article by Dr. John Lee about why the risks of conventional HRT outweigh the benefits, and how major research, including the Women’s Health Inititive (WHI) and the Million Women Study have finally made that clear.
Menopause Book Chapter 1 Here’s where you can read chapter one of Dr. John Lee and Virginia Hopkins’ best-selling book, What Your Doctor May Not Tell You About Menopause.
Natural Progesterone – What Women Say What women say about how natural progesterone has helped them restore hormone balance and combat estrogen dominance, plus what natural progesterone is and its effects in the body.
Progesterone and Estrogen Effects Progesterone and estrogen balance each other in the body. Here is a list of estrogen’s effects on the body, and the complementary effects of progesterone. Both hormones have important effects throughout the body.
Cancer Warning on Progesterone Cream Labels Does the warning on progesterone cream labels that progesterone may cause cancer really mean anything? Not much, and here’s why.
Symptoms of Estrogen Dominance Estrogen dominance is a term coined by Dr. Lee, and this is his famous (and much copied) list of the symptoms and conditions associated with estrogen dominance.
Estrogen Pill vs. Estrogen Cream or Patch – Which Works Best? Dr. Jane Murray explains why the estrogen patch or estrogen cream is better for a woman’s body than an estrogen pill.
Estriol – the Safe Estrogen Hormone Estriol is a safe estrogen hormone that has been used for decades in Europe to treat hot flashes and vaginal dryness.
Estrogen Advice from Dr. John Lee Dr. John Lee gives straight answers to what women want to know about estrogen, including what kind of estrogen to take and how much.
Brain Research and Progesterone Emerging brain research shows that progesterone affects every neural cell in the brain and is made in some parts of the brain.
NEW! 10 Steps to Hormone Balance – the e-booklet! A downloadable e-booklet designed especially to help women approach hormone balance one step at a time. Includes Hormone Balance Test and Symptoms Chart.
Test Hormone Levels The blood spot test is a hormone test kit that measures hormone levels in women and men.
Follow this link:
How to Find a Bioidentical Hormone Doctor
Recommendation and review posted by Bethany Smith
Reviewed January 2010
The Y chromosome is one of the two sex chromosomes in humans (the other is the X chromosome). The sex chromosomes form one of the 23 pairs of human chromosomes in each cell. The Y chromosome spans more than 59 million building blocks of DNA (base pairs) and represents almost 2 percent of the total DNA in cells.
Each person normally has one pair of sex chromosomes in each cell. The Y chromosome is present in males, who have one X and one Y chromosome, while females have two X chromosomes.
Identifying genes on each chromosome is an active area of genetic research. Because researchers use different approaches to predict the number of genes on each chromosome, the estimated number of genes varies. The Y chromosome likely contains 50 to 60 genes that provide instructions for making proteins. Because only males have the Y chromosome, the genes on this chromosome tend to be involved in male sex determination and development. Sex is determined by the SRY gene, which is responsible for the development of a fetus into a male. Other genes on the Y chromosome are important for male fertility.
Many genes are unique to the Y chromosome, but genes in areas known as pseudoautosomal regions are present on both sex chromosomes. As a result, men and women each have two functional copies of these genes. Many genes in the pseudoautosomal regions are essential for normal development.
Genes on the Y chromosome are among the estimated 20,000 to 25,000 total genes in the human genome.
Many genetic conditions are related to changes in particular genes on the Y chromosome. This list of disorders associated with genes on the Y chromosome provides links to additional information.
Changes in the structure or number of copies of a chromosome can also cause problems with health and development. The following chromosomal conditions are associated with such changes in the Y chromosome.
In most individuals with 46,XX testicular disorder of sex development, the condition results from an abnormal exchange of genetic material between chromosomes (translocation). This exchange occurs as a random event during the formation of sperm cells in the affected person’s father. The translocation affects the gene responsible for development of a fetus into a male (the SRY gene). The SRY gene, which is normally found on the Y chromosome, is misplaced in this disorder, almost always onto an X chromosome. A fetus with an X chromosome that carries the SRY gene will develop as a male despite not having a Y chromosome.
Males with 47,XYY syndrome have one X chromosome and two Y chromosomes in each cell, for a total of 47 chromosomes. It is unclear why an extra copy of the Y chromosome is associated with tall stature, learning problems, and other features in some boys and men.
Some males with 47,XYY syndrome have an extra Y chromosome in only some of their cells. This phenomenon is called 46,XY/47,XYY mosaicism.
48,XXYY syndrome is caused by the presence of an extra X chromosome and an extra Y chromosome in a male’s cells. Extra genetic material from the X chromosome interferes with male sexual development, preventing the testes from functioning normally and reducing the levels of testosterone (a hormone that directs male sexual development) in adolescent and adult males. Extra copies of genes from the pseudoautosomal region of the extra X and Y chromosome contribute to the signs and symptoms of 48,XXYY syndrome; however, the specific genes have not been identified.
Y chromosome infertility is usually caused by deletions of genetic material in regions of the Y chromosome called azoospermia factor (AZF) A, B, or C. Genes in these regions are believed to provide instructions for making proteins involved in sperm cell development, although the specific functions of these proteins are unknown.
Deletions in the AZF regions may affect several genes. The missing genetic material likely prevents production of a number of proteins needed for normal sperm cell development, resulting in an inability to father children.
Chromosomal conditions involving the sex chromosomes often affect sex determination (whether a person has the sexual characteristics of a male or a female), sexual development, and the ability to have children (fertility). The signs and symptoms of these conditions vary widely and range from mild to severe. They can be caused by missing or extra copies of the sex chromosomes or by structural changes in these chromosomes.
Rarely, males may have more than one extra copy of the Y chromosome in every cell (polysomy Y). For example, the presence of two extra Y chromosomes is written as 48,XYYY. The extra genetic material in these cases can lead to skeletal abnormalities, decreased IQ, and delayed development, but the features of these conditions are variable.
Geneticists use diagrams called ideograms as a standard representation for chromosomes. Ideograms show a chromosome’s relative size and its banding pattern. A banding pattern is the characteristic pattern of dark and light bands that appears when a chromosome is stained with a chemical solution and then viewed under a microscope. These bands are used to describe the location of genes on each chromosome.
You may find the following resources about the Y chromosome helpful. These materials are written for the general public.
You may also be interested in these resources, which are designed for genetics professionals and researchers.
The Handbook provides basic information about genetics in clear language.
These links provide additional genetics resources that may be useful.
The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? in the Handbook.
The rest is here:
Y chromosome – Genetics Home Reference
Recommendation and review posted by Bethany Smith
Ifyou are reading this book, you are probably interested in life extension and antiaging concepts. Aging makes us increasingly vulnerable to alcohol-induced hangover, liver injury, and damage to the central nervous system. Because alcohol consumption produces toxic compounds and causes vitamin deficiencies, in the best of all possible worlds it would be better not to drink alcohol at all. For those who still want to drink, it is possible to do so more safely. The first piece of advice would be to drink only moderately and follow the preventive measures outlined in this protocol.
Warning:What follows is for those who choose to drink moderately. This advice is not for those who suffer from alcoholism. Simply put, an alcoholic has “lost the power of choice in drink” and is “without defense against the first drink.” In short, an alcoholic cannot drink safely. The Foundation is all too aware that an alcoholic may easily misinterpret the following information as a license to drink. It is not. It is only for those who drink by choice and do so in moderation.
The consumption of alcohol results in the formation of two very toxic compounds, acetaldehyde and malondialdehyde. These compounds generate massive free-radical damage to cells throughout the body. The free-radical damage generated by these alcohol metabolites creates an effect in the body similar to that caused by radiation poisoning. That is the reason why people feel so sick the day after consuming too much alcohol. If the proper combination of antioxidants is taken at the time the alcohol is consumed or before the inebriated individual goes to bed, the hangover and much of the cellular damage caused by alcohol may be prevented.
Aging makes us increasingly vulnerable to alcohol-induced hangover, liver injury, and damage to the central nervous system. In the elderly, alcohol- and drug-induced injury are more common and more serious, and recovery is more difficult.
Nutrients that neutralize alcohol byproducts and protect cells against the damaging effects of alcohol include vitamin C, vitamin B1, the amino acids S-allyl-cysteine and glutathione, vitamin E, and selenium (Sprince et al. 1975; Hell et al. 1976; Loguercio et al. 1993; van Zandwijk 1995; Marotta et al. 2001). There are several commercial preparations that can be taken at the time the alcohol is consumed or before bedtime to help prevent a hangover. One of these is called Anti-Alcohol Antioxidants. The ingredients in this formula will help prevent hangover while providing protection against the damaging byproducts of alcohol metabolism.
A study in the journal Alcohol showed how antioxidants could protect against brain damage. The study concluded by stating:
chronic pretreatment with vitamin E prevents alcohol-induced vascular injury and pathology in the brain (Altura et al. 1999).
Another study in the journalArteryconfirmed a specific toxic metabolite of alcohol (acetaldehyde) and identified an antidote (N-acetyl-cysteine) (Vasdev et al. 1995). Here is an excerpt:
All known pathways of ethanol metabolism result in the production of acetaldehyde, a highly reactive compound. N-acetyl cysteine, an analogue of the dietary amino acid cysteine, binds acetaldehyde, thus preventing its damaging effect on physiological proteins.
These findings should not surprise anyone who understands that the ingestion of alcohol inflicts massive free-radical damage throughout the body. When a person is exposed to a known toxic substance (such as alcohol), it makes sense to take an antidote (antioxidants) to provide at least partial protection against the short-term (hangover) and long-term (degenerative disease) effects.
Supplementation with 400-800 mg of SAMe twice a day will help support healthy liver function. For those who cannot afford SAMe, supplementation with 500 mg of trimethylglycine (TMG, also known as glycine betaine), 800 micrograms of folic acid, and 500 micrograms of vitamin B12, taken twice a day, could help the liver to synthesize S-adenosylmethionine.
A study inAnnals of Internal Medicinecompiled the enormous cost of lost productivity induced by hangovers (Wiese et al. 2000). Here is an excerpt from this study:
The alcohol hangover is characterized by headache, tremulousness, nausea, diarrhea, and fatigue combined with decreased occupational, cognitive, or visual-spatial skill performance. In the United States, related absenteeism and poor job performance cost $148 billion annually (average annual cost per working adult, $2000). Although hangover is associated with alcoholism, most of its cost is incurred by the light-to-moderate drinker. Patients with hangover may pose substantial risk to themselves and others despite having a normal blood alcohol level. Hangover may also be an independent risk factor for cardiac death.
Based on these statistics, hangover causes a significant economic loss in the United States. The staggering cost of alcoholic hangover could be significantly mitigated if drinkers took the right antioxidants before going to bed.
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Ann Arbor Life Extension
Recommendation and review posted by Bethany Smith
In the past year, Japan has accelerated its position as a hub for regenerative medicine research, largely driven by support from Prime Minister Shinzo Abe who has identified regenerative medicine and cellular therapy as key to the Japans strategy to drive economic growth. The Prime Minister has encouraged a growing range of collaborations between private industry and academic partners through an innovative legal framework approved last fall. He has also initiated campaigns to drive technological advances in drugs and devices by connecting private companies with public funding sources. The result has been to drive progress in both basic and applied research involving induced pluripotent stem cells (iPS cells) and related stem cell technologies.
Indeed, 2013 represented a landmark year in Japan, as it saw the first cellular therapy involving transplant of iPS cells into humans initiated at the RIKEN Center in Kobe, Japan. The RIKEN Center is Japans largest, most comprehensive research institution, backed by both Japans Health Ministry and government. To speed things along, RIKEN did not seek permission for a clinical trial involving iPS cells, but instead applied for a type of pretrial clinical research allowed under Japanese regulations.
As such, this pretrial clinical research allowed the RIKEN research team to test the use of iPS cells for the treatment of wet-type age-related macular degeneration (AMD) on a very small scale, in only a handful of patients. Unfortunately, this trial was paused in 2015 due to safety concerns and is currently on hold pending further investigation. Regardless, the trial has set a new international standard for considering iPS cells as a viable cell type to investigate for clinical purposes.
If this iPS cell trial is ultimately reinstated, it will help to accelerate the acceptance of cellular therapies within other countries. Currently, the main concern surrounding iPS cell-based cellular therapy isthe fear of creating multiplying cell populations within patients. Even treatments using embryonic stem cells, which have been cultured and studied for decades, are still in very early clinical trials, so it is not surprising that clinical trials using iPS cells are being conducted on a small-scale, experimental level.
Japan has a unique affection for iPS cells, as the cells were originally discovered by the Japanese scientist, Shinya Yamanaka of Kyoto University. Mr. Yamanaka was awarded the Nobel Prize in Physiology or Medicine for 2012, an honor shared jointly with John Gurdon, for the discovery that mature cells can be reprogrammed to become pluripotent. In addition, Japans Education Ministry said its planning to spend 110 billion yen ($1.13 billion) on induced pluripotent stem cell research during the next 10 years, and the Japanese parliament has been discussing bills that would speed the approval process and ensure the safety of such treatments. In April, Japanese parliament even passed a law calling for Japan to make regenerative medical treatments like iPSC technology available for its citizens ahead of the rest of the world. If those forces were not enough, Masayo Takahashi of the RIKEN Center for Developmental Biology in Kobe, Japan, who is heading the worlds first clinical research using iPSCs in humans, was also chosen by the journal Natureas one of five scientists to watch in 2014.
In summary, Japan is the clear global leader with regard to investment in iPS cell technologies and therapies. While progress with stem cells has not been without setbacks within Japan, including a recent scandal at the RIKEN Institute that involved falsely manipulated research findings and the aforementioned hold on the first clinical trial involving transplant of an iPS cell product into humans, Japan has emerged from these troubles to become the most liberalized and progressive nation pursuing the development of iPS cell products and services.
To learn more about induced pluripotent stem cell (iPSC)industry trends and events, view the Compete 2015-16 Induced Pluripotent Stem Cell (iPSC) Industry Report.
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BioInformant is the only research firm that has served the stem cell sector since it emerged. Our management team comes from a BioInformatics background the science of collecting and analyzing complex genetic codes and applies these techniques to the field of market research. BioInformant has been featured on news outlets including the Wall Street Journal, Nature Biotechnology, CBS News, Medical Ethics, and the Center for BioNetworking.
Serving Fortune 500 leaders that include GE Healthcare, Pfizer, Goldman Sachs, Beckton Dickinson, and Thermo Fisher Scientific, BioInformant is your global leader in stem cell industry data.
Footnotes  Dvorak, K. (2014).Japan Makes Advance on Stem-Cell Therapy [Online]. Available at: http://online.wsj.com/news/articles/SB10001424127887323689204578571363010820642. Web. 14 Apr. 2015.  Note: In the United States, some patients have been treated with retina cells derived from embryonic stem cells (ESCs) to treat macular degeneration. There was a successful patient safety test for this stem cell treatment last year that was conducted at the Jules Stein Eye Institute in Los Angeles. The ESC-derived cells used for this study were developed by Advanced Cell Technology, Inc, a company located in Marlborough, Massachusetts.  Dvorak, K. (2014).Japan Makes Advance on Stem-Cell Therapy [Online]. Available at: http://online.wsj.com/news/articles/SB10001424127887323689204578571363010820642. Web. 8 Apr. 2015.  Ibid.  Riken.jp. (2014).RIKEN researcher chosen as one of five scientists to watch in 2014 | RIKEN [Online]. Available at: http://www.riken.jp/en/pr/topics/2014/20140107_1/. Web. 14 Apr. 2015.
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Japan Most Liberalized Market for iPS Cell Therapy …
Recommendation and review posted by Bethany Smith
We observed similar stem cell plasticity when we purified and tested the myoepithelial stem cells from sweat glands (Lu et al., 2012; Blanpain and Fuchs, 2014). Similar to myoepithelial stem cells of mammary glands, these stem cells normally act unipotently and only replenish dying myoepithelial cells of the gland. However, when purified by fluorescence activated cell sorting (FACS) and transplanted directly into a mammary fat pad, the stem cells can regenerate the complete bi-layered gland, and the new luminal cells secrete sweat. Moreover, when engrafted to the skin, these stem cells can make epidermis. An area of interest in my lab is to understand the environmental cues that dictate the fascinating plasticity of epithelial stem cells, and to elucidate the chromatin remodeling that leads to the changes in gene expression necessary to generate different tissues from a common progenitor.
To understand how a stem cell chooses its differentiation pathway, we have taken several approaches. An ongoing approach of the lab is to express different fluorescent proteins under the control of various skin promoters, active at different stages in stem cells and their lineages. Through FACS, we’ve purified cells at different time points along the lineages and generated a battery of lineage-specific profiles, enabling us to define at an mRNA (RNA-seq) and chromatin (ChIP-seq) level how stem cells change as they transition from quiescence to activation to lineage determination. Our global objective is to exploit this information to understand how stem cells receive signals, change their program of gene expression and select a lineage. We also want to understand the functional significance of these changes. The beauty of the hair follicle as a model is that it is currently the only system where sufficient quantities of stem cells can be isolated directly from their native niche in order to carry out whole-genome wide analyses in vivo. This eliminates the caveats arising from culturing cells, namely induction of a stress response and large-scale epigenetic changes in gene expression.
For the hair follicle, >150 mRNAs are selectively upregulated in the bulge stem cells relative to their short-lived progeny (Tumbar et al., 2004; Blanpain et al., 2004; Keyes et al., 2013). A number of these changes are in transcription factors and epigenetic regulators. Weve conducted in vivo chromatin immunoprecipitation and high throughput sequencing (ChIP-seq) on chromatin from hair follicle stem cells (HFSCs) and their short-lived progeny. Bioinformatics reveals which genes bind these transcription factors, and how this changes as the stem cells progress to form transiently dividing cells that then terminally differentiate along one of the 7 distinct concentric cell layers that constitute the hair and its channel. By conducting high throughput RNA sequencing (RNA-seq) on HFSCs lacking each of these genes, weve learned which target genes depend upon binding these transcription factors. Finally, by engineering inducible-conditional knockouts to selectively remove these transcription factors in the stem cells, weve learned the physiological relevance of these factors.
Based upon these analyses, TCF3/TCF4, LHX2 and SOX9 are all essential for maintaining the hair follicle stem cells in their native niche (Nguyen et al., 2006; 2009; Rhee et al., 2006; Folgueras et al., 2013; Lien et al., 2011; 2014; Nowak et al., 2008; Kadaja et al., 2014). In addition, LHX2 represses sebaceous gland differentiation: following its loss, the stem cell niche soon becomes a sebaceous gland (Folgueras et al., 2013). SOX9 represses epidermal differentiation: following its loss, the niche becomes an epidermal cyst (Kadaja et al., 2014). TCF3 and TCF4 repress HF differentiation: following their loss, quiescent HFSCs precociously activate a new hair cycle (Lien et al., 2014). TCF3 and TCF4 can partner with -catenin, which is stabilized and becomes nuclear upon Wnt signaling: if -catenin is silenced in the quiescent HFSCs, they never reenter a new hair cycle. In their native niche, quiescent HFSCs express a transcriptional repressor TLE4 which binds to TCF3 and TCF4: our findings are consistent with the view that Wnt signaling functions by relieving TCF3/4/TLE4-mediated repression (Lien et al., 2014).
NFATc1 is required for maintaining HFSC quiescence, and in its absence, HFs cycle precociously (Horsley et al., 2008). Additionally, NFATc1 is downstream of BMP signaling, offering a potential explanation as to why BMP signaling must be lowered to activate hair cycling. A major feature of the aging HFSC signature is elevated NFATc1 target genes, and we can stimulate old follicles by inhibiting NFATc1 (Keyes et al., 2013). A major question still to be answered is whether HFSCs have an endless capacity for hair cycling and whether this same phenomenon operates in aging scalp hairs in humans. If so, these findings may open new doors for future therapeutics.
NFiB is a transcription factor which is specific to the HFSCs, but functions by repressing the expression of genes that are essential for the differentiation of the melanocyte stem cells, which reside within the same stem cell niche (Chang et al., 2013). These two stem cell populations must be activated at the same time so that differentiating melanocytes can transfer pigment to the differentiating hair cells to provide the natural coloring to our hair. Loss of NFiB uncouples this crosstalk and leads to the precocious activation of a key NFiB target gene that encodes a secreted melanocyte differentiation factor (Chang et al., 2013).
There are a number of additional transcription factors and epigenetic regulators which are enhanced in the complex milieu of HF stem cell chromatin, and there is still much to be learned. Of the epigenetic regulators, weve thus far examined only the role of polycomb chromatin repressor complexes, which weve shown function critically in controlling the fate switch from a stem cell to a committed, transit-amplifying state (Ezhkova et al., 2009; 2011; Lien et al., 2011). In coming years, we will continue to systematically work our way through the functional significance and mechanism of action of epigenetic and transcriptional controls on stem cells as they transit from a quiescent to activated to committed state. When coupled with our recent ability to efficiently knockdown genes in a few days using lentiviral-mediated shRNA delivery (Beronja et al., 2010), this now becomes a powerful tool for exploiting bioinformatics analyses to gain biological insights.
Our ultimate goal is to understand how external signals from the surrounding niche microenvironment impact chromatin dynamics to achieve tissue production. Equally important will be the expression of specific genes that enables them to remodel their cytoskeleton and adhesive contacts and either form a stratified epidermis or an epithelial bud that can then develop into a hair follicle (Perez-Moreno et al., 2003; Blanpain and Fuchs, 2009; Hsu et al., 2014). While our model is the skin, the problem is a general one of how a single epithelial stem cell gives rise to a spatially organized, functional tissue. It is also integrally linked to understanding the basis of cancer progression.
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The Rockefeller University Stem Cells of the Skin and …
Recommendation and review posted by Bethany Smith
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For years, the cornerstones of cancer treatment have been surgery, chemotherapy, and radiation therapy. Over the last decade, targeted therapies like imatinib (Gleevec) and trastuzumab (Herceptin)drugs that target cancer cells by homing in on specific molecular changes seen primarily in those cellshave also emerged as standard treatments for a number of cancers.
Illustration of the components of second- and third-generation chimeric antigen receptor T cells. (Adapted by permission from the American Association for Cancer Research: Lee, DW et al. The Future Is Now: Chimeric Antigen Receptors as New Targeted Therapies for Childhood Cancer. Clin Cancer Res; 2012;18(10); 278090. doi:10.1158/1078-0432.CCR-11-1920)
And now, despite years of starts and stutter steps, excitement is growing for immunotherapytherapies that harness the power of a patients immune system to combat their disease, or what some in the research community are calling the fifth pillar of cancer treatment.
One approach to immunotherapy involves engineering patients own immune cells to recognize and attack their tumors. And although this approach, called adoptive cell transfer (ACT), has been restricted to small clinical trials so far, treatments using these engineered immune cells have generated some remarkable responses in patients with advanced cancer.
For example, in several early-stage trials testing ACT in patients with advanced acute lymphoblastic leukemia (ALL) who had few if any remaining treatment options, many patients cancers have disappeared entirely. Several of these patients have remained cancer free for extended periods.
Equally promising results have been reported in several small trials involving patients with lymphoma.
These are small clinical trials, their lead investigators cautioned, and much more research is needed.
But the results from the trials performed thus far are proof of principle that we can successfully alter patients T cells so that they attack their cancer cells, said one of the trial’s leaders, Renier J. Brentjens, M.D., Ph.D., of Memorial Sloan Kettering Cancer Center (MSKCC) in New York.
Adoptive cell transfer is like giving patients a living drug, continued Dr. Brentjens.
Thats because ACTs building blocks are T cells, a type of immune cell collected from the patients own blood. After collection, the T cells are genetically engineered to produce special receptors on their surface called chimeric antigen receptors (CARs). CARs are proteins that allow the T cells to recognize a specific protein (antigen) on tumor cells. These engineered CAR T cells are then grown in the laboratory until they number in the billions.
The expanded population of CAR T cells is then infused into the patient. After the infusion, if all goes as planned, the T cells multiply in the patients body and, with guidance from their engineered receptor, recognize and kill cancer cells that harbor the antigen on their surfaces.
Although adoptive cell transfer has been restricted to small clinical trials so far, treatments using these engineered immune cells have generated some remarkable responses in patients with advanced cancer.
This process builds on a similar form of ACT pioneered by Steven Rosenberg, M.D., Ph.D., and his colleagues from NCIs Surgery Branch for patients with advanced melanoma.
The CAR T cells are much more potent than anything we can achieve with other immune-based treatments being studied, said Crystal Mackall, M.D., of NCIs Pediatric Oncology Branch (POB).
Even so, investigators working in this field caution that there is still much to learn about CAR T-cell therapy. But the early results from trials like these have generated considerable optimism.
CAR T-cell therapy eventually may become a standard therapy for some B-cell malignancies like ALL and chronic lymphocytic leukemia, Dr. Rosenberg wrote in a Nature Reviews Clinical Oncology article.
More than 80 percent of children who are diagnosed with ALL that arises in B cellsthe predominant type of pediatric ALLwill be cured by intensive chemotherapy.
For patients whose cancers return after intensive chemotherapy or a stem cell transplant, the remaining treatment options are close to none, said Stephan Grupp, M.D., Ph.D., of the Childrens Hospital of Philadelphia (CHOP) and the lead investigator of a trial testing CAR T cells primarily in children with ALL. This treatment may represent a much-needed new option for such patients, he said.
Trials of CAR T cells in adults and children with leukemia and lymphoma have used T cells engineered to target the CD19 antigen, which is present on the surface of nearly all B cells, both normal and cancerous.
In the CHOP trial, which is being conducted in collaboration with researchers from the University of Pennsylvania, all signs of cancer disappeared (a complete response) in 27 of the 30 patients treated in the study, according to findings published October 16 in the New England Journal of Medicine.
Nineteen of the 27 patients with complete responses have remained in remission, the study authors reported, with 15 of these patients receiving no further therapy and 4 patients withdrawing from the trial to receive other therapy.
According to the most recent data from a POB trial that included children with ALL, 14 of 20 patients had a complete response. And of the 12 patients who had no evidence of leukemic cells, called blasts, in their bone marrow after CAR T-cell treatment, 10 have gone on to receive a stem cell transplant and remain cancer free, reported the studys lead investigator, Daniel W. Lee, M.D., also of the POB.
Dr. Crystal Mackall
Our findings strongly suggest that CAR T-cell therapy is a useful bridge to bone marrow transplant for patients who are no longer responding to chemotherapy, Dr. Lee said.
Similar results have been seen in phase I trials of adult patients conducted at MSKCC and NCI.
In findings published in February 2014, 14 of the 16 participants in the MSKCC trial treated to that point had experienced complete responses, which in some cases occurred 2 weeks or sooner after treatment began. Of those patients who were eligible, 7 underwent a stem cell transplant and are still cancer free.
The NCI-led trial of CAR T cells included 15 adult patients, the majority of whom had advanced diffuse large B-cell lymphoma. Most patients in the trial had either complete or partial responses, reported James Kochenderfer, M.D., and his NCI colleagues.
Our data provide the first true glimpse of the potential of this approach in patients with aggressive lymphomas that, until this point, were virtually untreatable, Dr. Kochenderfer said. [NCI Surgery Branch researchers have also reported promising results from one of the first trials testing CAR T cells derived from donors, rather than the patients themselves, to treat leukemia and lymphoma.]
Other findings from the trials have been encouraging, as well. For example, the number of CAR T cells increased dramatically after infusion into patients, as much as 1,000-fold in some individuals. In addition, after infusion, CAR T cells were detected in the central nervous system, a so-called sanctuary site where solitary cancer cells that have evaded chemotherapy or radiation may hide. In two patients in the NCI pediatric trial, the CAR T-cell treatment eradicated cancer that had spread to the central nervous system.
If CAR T cells can persist at these sites, it could help fend off relapses, Dr. Mackall noted.
CAR T-cell therapy can cause several worrisome side effects, perhaps the most troublesome being cytokine-release syndrome.
The infused T cells release cytokines, which are chemical messengers that help the T cells carry out their duties. With cytokine-release syndrome, there is a rapid and massive release of cytokines into the bloodstream, which can lead to dangerously high fevers and precipitous drops in blood pressure.
Cytokine-release syndrome is a common problem in patients treated with CAR T cells. In the POB and CHOP trials, patients with the most extensive disease prior to receiving the CAR T cells were more likely to experience severe cases of cytokine-release syndrome.
For most patients, trial investigators have reported, the side effects are mild enough that they can be managed with standard supportive therapies, including steroids.
The research team at CHOP noticed that patients experiencing severe reactions all had particularly high levels of IL-6, a cytokine that is secreted by T cells and macrophages in response to inflammation. So they turned to two drugs that are approved to treat inflammatory conditions like juvenile arthritis: etanercept (Enbrel) and tocilizumab (Actemra), the latter of which blocks IL-6 activity.
The patients had excellent responses to the treatment, Dr. Grupp said. We believe that [these drugs] will be a major part of toxicity management for these patients.
The other two teams subsequently used tocilizumab in several patients. Dr. Brentjens agreed that both drugs could become a useful way to help manage cytokine-release syndrome because, unlike steroids, they dont appear to affect the infused CAR T cells activity or proliferation.
Even with these encouraging preliminary findings, more research is needed before CAR T-cell therapy becomes a routine option for patients with ALL.
We need to treat more patients and have longer follow-up to really say what the impact of this therapy is [and] to understand its true performance characteristics, Dr. Grupp said.
We need to treat more patients and have longer follow-up to really say what the impact of this therapy is [and] to understand its true performance characteristics.
Dr. Stephan Grupp
Several other trials testing CAR T cells in children and adults are ongoing and, with greater interest and involvement from the pharmaceutical and biotechnology sector, more trials testing CAR T cells are being planned.
Researchers are also studying ways to improve on the positive results obtained to date, including refining the process by which the CAR T cells are produced.
Research groups like Dr. Brentjens are also working to make a superior CAR T cell, including developing a better receptor and identifying better targets.
For example, Dr. Lee and his colleagues at NCI have developed CAR T cells that target the CD22 antigen, which is also present on most B cells, although in smaller quantities than CD19. The CD22-targeted T cells, he believes, could be used in concert with CD19-targeted T cells as a one-two punch in ALL and other B-cell cancers. NCI researchers hope to begin the first clinical trial testing the CD22-targeted CAR T cells in November 2014.
Based on the success thus far, several research groups across the country are turning their attention to developing engineered T cells for other cancers, including solid tumorslike pancreatic and brain cancers.
The stage has now been set for greater progress, Dr. Lee believes.
NCI investigators, for example, now have a platform to plug and play better CARs into that system, without a lot of additional R&D time, he continued. Everything else should now come more rapidly.
See the rest here:
CAR T-Cell Immunotherapy for ALL – National Cancer Institute
Recommendation and review posted by Bethany Smith
Proband, proposito (male proband), or proposita (female proband) is a term used most often in medical genetics and other medical fields to denote a particular subject (person or animal) being studied or reported on. On pedigrees, the proband is noted with a square (male) or circle (female) shaded accordingly. It is important to denote the proband, so that the relationship to other individuals can be seen and patterns established.
In most cases, the proband is the first affected family member who seeks medical attention for a genetic disorder. Among the ancestors of the proband, there may be other subjects with the manifest disease, but the proband typically refers to the member seeking medical attention or being studied, even if affected ancestors are known. Often affected ancestors are unknown due to the lack of information regarding those individuals or about the disease at the time they lived. Other ancestors might be undiagnosed due to the incomplete penetrance or variable expressivity.
The diagnosis of a proband raises the index of suspicion for the proband’s relatives and some of them may be diagnosed with the same disease. Conventionally, when drawing a pedigree chart, instead of the first diagnosed person, the proband may be chosen from among the affected ancestors (parents, grandparents) from the first generation where the disease is found.
The term proband is also used in genealogy, where it denotes the root node of an ahnentafel, also referred to as the progenitor.
Go here to read the rest:
Proband – Wikipedia, the free encyclopedia
Recommendation and review posted by Bethany Smith
A bone marrow transplant, alsoknown as a haemopoietic stem cell transplant, replaces damaged bone marrow with healthy bone marrow stem cells.
Bone marrow is aspongytissue found in the hollow centres of some bones. It contains specialist stem cells, which produce the body’s blood cells.
Stem cells in bone marrow produce three important types of blood cells:
Bone marrow transplants are often needed to treat conditions thatdamage bone marrow. If bone marrow is damaged, it is no longer able to produce normal blood cells. The new stem cells take over blood cellproduction.
Conditions that bone marrow transplants are used to treat include:
Read more about why a bone marrow transplantis needed.
A bone marrow transplant involves taking healthy stem cells from the bone marrow of one person and transferring them to the bone marrow of another person.
In some cases, it may be possible to take the bone marrow from your own body. This is known as an autologous transplantation. Before it is returned, the bone marrow is cleared of any damaged or diseased cells.
A bone marrowtransplant has five stages. These are:
Having a bone marrow transplant can be an intensive and challenging experience. Many people take up to a year to fully recover from the procedure.
Read more about what happens during a bone marrow transplant.
Bone marrow transplants are usually only recommended if:
Read more about who can have a bone marrow transplant.
Bone marrow transplants arecomplicated procedures with significant risks.
In some cases, the transplanted cells (graft cells) recognise the recipient’s cells as “foreign”and try to attack them. This is known as graft versus host disease (GvHD).
The risk of infectionis alsoincreased because your immune system is weakened when you’re conditioned (prepared) for the transplant.
Read more about the risks of having a bone marrow transplant.
It’s nowpossible to harvest stem cells from sources other than bone marrow.
Peripheral blood stem cell donation involves injectinga medicine into the donor’s blood thatcauses the stem cells to moveout of the bone marrow and into the bloodstream where theycan be harvested (collected).
The advantage of this type of stem cell donation is that the donor doesn’t needa general anaesthetic.
Stem cells can also be collectedfrom the placenta and umbilical cord of a newborn baby and stored in a laboratory until they’re needed.
Cord blood stem cells are very usefulbecause they don’t need to be as closely matched as bone marrow or peripheral blood stem cells for a successful outcome.
Find out more about theNHS Cord Blood Bank(external link).
Page last reviewed: 18/02/2014
Next review due: 18/02/2016
Originally posted here:
Bone marrow transplant – NHS Choices
Recommendation and review posted by Bethany Smith
GMAP: A Genomic Mapping and Alignment Program for mRNA and EST Sequences, and GSNAP: Genomic Short-read Nucleotide Alignment Program
Links are provided below in parentheses for users who wish to download the files with a command-line tool, like wget.
As of December 2011, there is a new mailing list at gsnap-users for issues relating to both GMAP and GSNAP. You can sign up there to receive release notices, ask questions, or see previous messages. If you have a bug to report or a feature to request, you can send email to firstname.lastname@example.org (you will have to subscribe to the list first, though, or the message will be held for me to approve) or directly to me at Thomas Wu (email@example.com).
Pre-built genome database for GMAP and GSNAP. This will work only with versions 2013-10-01 until 2014-03-28, and lacks the suffix array that helps GSNAP achieve high speeds. An example database for the current versions 2014-04-01 and later is pending. In the meantime, you should build your own genome database with the gmap_build program included with this software.
README file from the source code distribution. Contains basic usage information.
Software demonstration given at ISMB 2005. Contains various examples of GMAP usage. [Slides]
Supplementary information for Bioinformatics 2005 publication on GMAP:
GMAP – Genentech
Recommendation and review posted by Bethany Smith
CTBR/RTRN collaboration uncovers new neurological disorder treatment and prevention properties of green tea.
CC Image courtesy of Brandie Kajino on Flickr
Come chat with us at our exhibitor boothsat this year’s scientific conferencesto learn more about CTBR’s research programs, activities, and opportunities.
Pictured: CTBR member Dr. Ben Ortiz (left) and RISE student Devin Cohen (right).
You can help keep our resources available for all future research. Simply cite the NIH/NIMHD RCMI Program at Hunter College, CUNY MD007599 in your posters and publications.
Read ScienceInsider’s interview with Dr. Eliseo Prez-Stable.
Follow us on twitter @CTBRHunter for the latest news and announcements!
7 of our members received professional development awards for pilot projects, seed funding, and more. Read about the awards.
UPDATE: Visit the symposium page for video links to all presentations, the meeting report and photos!
Read this article:
Welcome to The Center for Translational and Basic Research …
Recommendation and review posted by Bethany Smith
Genetic testing can be used to find out whether a person is carrying aspecific genetic mutation (altered gene) that causes a particular medical condition.
Itmay be carried out for anumber of reasons, including:
You will usually need to get a referral from your GP, or a specialist doctor if you have one, for genetic testing to be carried out speak to your GP or your doctor about the possibility of testing if you think you may need it.
Genetic testing usually involves having a sample of your blood or tissue taken. The sample will contain cells containing your DNA and can be tested to find out whether you are carrying a particular mutation and are at risk of developing a particular genetic condition.
In some cases, genetic testing can be carried out to see if a foetus is likely to be born with a certain genetic condition by testing samples of amniotic fluid (the fluid that surrounds the foetus in the womb) or chorionic villi cells (cells that develop into the placenta) extracted from the mother’s womb using a needle.
Depending on the condition(s) being tested for, the blood or cell samples will then be tested and examined in a genetics laboratory to check fora specific gene, a certain mutation on a specific gene or any mutation on aspecific gene.
In some cases, it may be necessary to check an entire gene for mutations, using a process called gene sequencing. This has to be done very carefully, and it can take a long time compared to most other hospital laboratory tests.
Depending on the specific mutation being tested for, it can take weeks or even months for the results of genetic tests to become available. This can be because the laboratory has to gather information to help them interpret what has been found.
It is also important to realise that it is not always possible to give definite answers after genetic testing. Sometimes it is necessary to wait to see if the person being tested or other relatives do, or do not develop a condition, and other tests may need to be performed.
You can find out more about genetic testing and how it is carried out by reading the leaflet: ‘What happens in a genetics laboratory?’ (PDF, 1.90Mb).
If your doctor thinks genetic testing may be appropriate in your case, you will usually be referred for genetic counselling as well.
Genetic counselling is a service that provides support, information and advice about genetic conditions. It is conducted by healthcare professionals who have been specially trained in the science of human genetics (a genetic counsellor or a clinical geneticist).
What happens during genetic counselling will depend on exactly why you’ve been referred. It may involve:
You will be given clear, accurate information so you can decide what’s best for you.
Your appointment will usually take place at your nearest NHS regional genetics centre. The British Society for Genetic Medicine has details for each of the genetics centres in the UK.
For couples at risk of having a child with a serious genetic condition, pre-implantation genetic diagnosis (PGD) may be an option.
PGD involves using in-vitro fertilisation (IVF), where eggs are removed from a woman’s ovaries before being fertilised with sperm in a laboratory. After a few days, the resulting embryos can be tested fora particular genetic mutation and a maximum of two unaffected embryos are transferred into the uterus.
While PGD has the advantage of avoiding the termination of foetuses affected byserious conditions, it also has a number of drawbacks. These include the modest success rate of achieving a pregnancy after IVF, as well as the substantial financial (PGD is not always available on the NHS) and emotional burdens of the combined IVF and PGD process.
Page last reviewed: 08/08/2014
Next review due: 08/08/2016
Follow this link:
Genetics – Genetic testing and counselling – NHS Choices
Recommendation and review posted by Bethany Smith
Thanks to advances in science and technology, Dr. Oz says people will one day be able to live longer, healthier lives. Dr. Oz says Wake Forest University is home of one of the country’s foremost tissue regeneration labs. “These are technologies that fascinate me because they could add decades to our life,” he says.
What is regenerative medicine? Dr. Anthony Atala, director of Wake Forest’s program, says his team is working to create cells, tissues and organs for patients who may need them. “Right now, of course, we have a limited life span because your parts are breaking down,” he says. “But imagine a time in the future when, once those parts start breaking down, you can just plug a new one right in.”
Watch Dr. Oz’s visit to the tissue regeneration lab.
Over the years, Dr. Atala’s researchers have grown nearly two dozen different types of body parts, including muscle, bones and a working heart valve. “I think if we start combining things like better prevention, better care, doing things better for your body, and just with regenerative medicine, we may push [our life spans] up to 120, 130 years,” Dr. Atala says.
Published on March 24, 2009
Recommendation and review posted by Bethany Smith
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Read more here:
Challenges in identifying the best source of stem cells …
Recommendation and review posted by Bethany Smith
In 2006, Shinya Yamanaka of Kyoto University in Japan was the first to disprove the previous notion that reversible cell differentiation of mammals was impossible. He reprogrammed a fully differentiated mouse cell into a pluripotent stem cell by introducing four genes, Oct-4, SOX2, KLF4, and Myc, into the mouse fibroblast through gene-carrying viruses. With this method, he and his coworkers created induced pluripotent stem cells (iPS cells), the key component in this experiment. Scientists have been able to conduct experiments that show the ability of iPS cells to treat and even cure diseases. In this experiment, tests were run on mice with inherited sickle-cell anemia. Skin cells were turned into cells containing genes that transformed the cells into iPS cells. These replaced the diseased sickled cells, curing the test mice. The reprogramming of the pluripotent stem cells in mice was successfully duplicated with human pluripotent stem cells within about a year of the experiment on the mice.
Sickle-cell anemia is a disease in which the body produces abnormally shaped red blood cells. Red blood cells are flexible and round, moving easily through the blood vessels. Infected cells are shaped like a crescent or sickle (the namesake of the disease). As a result of this disorder the hemoglobin protein in red blood cells is faulty. Normal hemoglobin bonds to oxygen, then releases it into cells that need it. The blood cell retains its original form and is cycled back to the lungs and re-oxygenated.
Sickle cell hemoglobin, however, after giving up oxygen, cling together and make the red blood cell stiff. The sickle shape also makes it difficult for the red blood cell to navigate arteries and causes blockages. This can cause intense pain and organ damage. The sickled red blood cells are fragile and prone to rupture. When the number of red blood cells decreases from rupture (hemolysis), anemia is the result. Sickle cells die in 1020 days as opposed to the traditional 120-day lifespan of a normal red blood cell.
Sickle cell anemia is inherited as an autosomal (meaning that the gene is not linked to a sex chromosome) recessive condition. This means that the gene can be passed on from a carrier to his or her children. In order for sickle cell anemia to affect a person, the gene must be inherited from both the mother and the father, so that the child has two recessive sickle cell genes (a homozygous inheritance). People who inherit one sickle cell gene from one parent and one normal gene from the other parent, i.e. heterozygous patients, have a condition called sickle cell trait. Their bodies make both sickle hemoglobin and normal hemoglobin. They may pass the trait on to their children.
The effects of sickle-cell anemia vary from person to person. People who have the disease suffer from varying degrees of chronic pain and fatigue. With proper care and treatment, the quality of health of most patients will improve. Doctors have learned a great deal about sickle cell anemia since its discovery in 1979. They know its causes, its effects on the body, and possible treatments for complications. Sickle cell anemia has no widely available cure. A bone marrow transplant is the only treatment method currently recognized to be able to cure the disease, though it does not work for every patient. Finding a donor is difficult and the procedure could potentially do more harm than good. Treatments for sickle cell anemia are generally aimed at avoiding crises, relieving symptoms, and preventing complications. Such treatments may include medications, blood transfusions, and supplemental oxygen.
During the first step of the experiment, skin cells (also known as fibroblasts) were collected from infected test mice and put in a culture. The fibroblasts were reprogrammed by infecting them with retroviruses that contained genes common to embryonic stem cells. These genes were the same four used by Yamanaka (Oct-4, SOX2, KLF4, and Myc) in his earlier study. The investigators were trying to produce cells with the potential to differentiate into any type of cell needed (i.e. pluripotent stem cells). As the experiment continued, the fibroblasts multiplied into identical copies of iPS cells. The cells were then treated to form the mutation needed to reverse the anemia in the mice. This was accomplished by restructuring the DNA containing the defective globin gene into DNA with the normal gene through the process of homologous recombination. The iPS cells then differentiated into blood stem cells, or hematopoietic stem cells. The hematopoietic cells were injected back into the infected mice, where they proliferate and differentiate into normal blood cells, curing the mice of the disease.[verification needed]
To determine whether the mice were cured from the disease, the scientists checked for the usual symptoms of sickle cell disease. They examined the blood for mean corpuscular volume (MCV) and red cell distribution width (RDW) and urine concentration defects. They also checked for sickled red blood cells. They examined the DNA through gel electrophoresis, checking for bands that display an allele that causes sickling. Compared to the untreated mice with the disease, which they used as a control, “the treated animals had marked increases in RBC counts, healthy hemoglobin, and packed cell volume levels”.
Researchers examined “the urine concentration defect, which results from RBC sickling in renal tubules and consequent reduction in renal medullary blood flow, and the general deteriorated systemic condition reflected by lower body weight and increased breathing.” They were able to see that these parts of the body of the mice had healed or improved. This indicated that “all hematological and systemic parameters of sickle cell anemia improved substantially and were comparable to those in control mice.” They cannot say if this will work in humans because a safe way to inject the genes for the induced pluripotent cells is still needed.
The reprogramming of the induced pluripotent stem cells in mice was successfully duplicated in humans within a year of the successful experiment on the mice. This reprogramming was done in several labs and it was shown that the iPS cells in humans were almost identical to original embryonic stem cells (ES cells) that are responsible for the creation of all structures in a fetus. An important feature of iPS cells is that they can be generated with cells taken from an adult, which would circumvent many of the ethical problems associated with working with ES cells. These iPS cells also have potential in creating and examining new disease models and developing more efficient drug treatments. Another feature of these cells is that they provide researchers with a human cell sample, as opposed to simply using an animal with similar DNA, for drug testing.
One major problem with iPS cells is the way in which the cells are reprogrammed. Using gene-carrying viruses has the potential to cause iPS cells to develop into cancerous cells. Also, an implant made using undifferentiated iPS cells, could cause a teratoma to form. Any implant that is generated from using these iPS cells would only be viable for transplant into the original subject that the cells were taken from. In order for these iPS cells to become viable in therapeutic use, there are still many steps that must be taken.
In the future, researchers hope that induced pluripotent cells may be used to treat other diseases. Pluripotency is a crucial part of disease treatment because iPS cells are capable of differentiation in a way that is very similar to embryonic stem cells which can grow into fully differentiated tissues. iPS cells also demonstrate high telomerase activity and express human telomerase reverse transcriptase, a necessary component in the telomerase protein complex. Also, iPS cells expressed cell surface antigenic markers expressed on ES cells. Also, doubling time and mitotic activity are cornerstones of ES cells, as stem cells must self-renew as part of their definition. As said, iPS cells are morphologically similar to embryonic stem cells. Each cell has a round shape, a large nucleolus and a small amount of cytoplasm. One day, the process may be used in practical settings to provide a fundamental way of regeneration.
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Induced pluripotent stem cells (also known as iPS cells or iPSCs) are a type of pluripotent stem cell that can be generated directly from adult cells. The iPSC technology was pioneered by Shinya Yamanakas lab in Kyoto, Japan, who showed in 2006 that the introduction of four specific genes encoding transcription factors could convert adult cells into pluripotent stem cells. He was awarded the 2012 Nobel Prize along with Sir John Gurdon “for the discovery that mature cells can be reprogrammed to become pluripotent.” 
Pluripotent stem cells hold great promise in the field of regenerative medicine. Because they can propagate indefinitely, as well as give rise to every other cell type in the body (such as neurons, heart, pancreatic, and liver cells), they represent a single source of cells that could be used to replace those lost to damage or disease.
The most well-known type of pluripotent stem cell is the embryonic stem cell. However, since the generation of embryonic stem cells involves destruction (or at least manipulation)  of the pre-implantation stage embryo, there has been much controversy surrounding their use. Further, because embryonic stem cells can only be derived from embryos, it has so far not been feasible to create patient-matched embryonic stem cell lines.
Since iPSCs can be derived directly from adult tissues, they not only bypass the need for embryos, but can be made in a patient-matched manner, which means that each individual could have their own pluripotent stem cell line. These unlimited supplies of autologous cells could be used to generate transplants without the risk of immune rejection. While the iPSC technology has not yet advanced to a stage where therapeutic transplants have been deemed safe, iPSCs are readily being used in personalized drug discovery efforts and understanding the patient-specific basis of disease.
Depending on the methods used, reprogramming of adult cells to obtain iPSCs may pose significant risks that could limit their use in humans. For example, if viruses are used to genomically alter the cells, the expression of oncogenes (cancer-causing genes) may potentially be triggered. In February 2008, scientists announced the discovery of a technique that could remove oncogenes after the induction of pluripotency, thereby increasing the potential use of iPS cells in human diseases. In April 2009, it was demonstrated that generation of iPS cells is possible without any genetic alteration of the adult cell: a repeated treatment of the cells with certain proteins channeled into the cells via poly-arginine anchors was sufficient to induce pluripotency. The acronym given for those iPSCs is piPSCs (protein-induced pluripotent stem cells).
iPSCs are typically derived by introducing a specific set of pluripotency-associated genes, or reprogramming factors, into a given cell type. The original set of reprogramming factors (also dubbed Yamanaka factors) are the genes Oct4 (Pou5f1), Sox2, cMyc, and Klf4. While this combination is most conventional in producing iPSCs, each of the factors can be functionally replaced by related transcription factors, miRNAs, small molecules, or even non-related genes such as lineage specifiers.
iPSC derivation is typically a slow and inefficient process, taking 12 weeks for mouse cells and 34 weeks for human cells, with efficiencies around 0.01%0.1%. However, considerable advances have been made in improving the efficiency and the time it takes to obtain iPSCs. Upon introduction of reprogramming factors, cells begin to form colonies that resemble pluripotent stem cells, which can be isolated based on their morphology, conditions that select for their growth, or through expression of surface markers or reporter genes.
Induced pluripotent stem cells were first generated by Shinya Yamanaka’s team at Kyoto University, Japan, in 2006. Their hypothesis was that genes important to embryonic stem cell function might be able to induce an embryonic state in adult cells. They began by choosing twenty-four genes that were previously identified as important in embryonic stem cells, and used retroviruses to deliver these genes to fibroblasts from mice. The mouse fibroblasts were engineered so that any cells that reactivated the ESC-specific gene, Fbx15, could be isolated using antibiotic selection.
Upon delivery of all twenty-four factors, colonies emerged that had reactivated the Fbx15 reporter, resembled ESCs, and could propagate indefinitely. They then narrowed their candidates by removing one factor at a time from the pool of twenty-four. By this process, they identified four factors, Oct4, Sox2, cMyc, and Klf4, which as a group were both necessary and sufficient to obtain ESC-like colonies under selection for reactivation of Fbx15.
Similar to ESCs, these first-generation iPSCs showed unlimited self-renewal and demonstrated pluripotency by contributing to lineages from all three germ layers in the context of embryoid bodies, teratomas, fetal chimeras. However, the molecular makeup of these cells, including gene expression and epigenetic marks, was somewhere between that of a fibroblast and an ESC, and the cells also failed to produce viable chimeras when injected into developing embryos.
In June 2007, the same group published a breakthrough study along with two other independent research groups from Harvard, MIT, and the University of California, Los Angeles, showing successful reprogramming of mouse fibroblasts into iPS cells. Unlike the first generation of iPS cells, these cells could produce viable chimeric mice and could contribute to the germline, the ‘gold standard’ for pluripotent stem cells. These cells were derived from mouse fibroblasts by retroviral-mediated expression of the same four transcription factors (Oct4, Sox2, cMyc, Klf4), but the researchers used a different marker to select for pluripotent cells. Instead of Fbx15, they used Nanog, a gene that is functionally important in ESCs. By using this different strategy, the researchers were able to create iPS cells that were more similar to ESCs than the first generation of iPS cells, and independently proved that it was possible to create iPS cells that are functionally identical to ESCs.
Unfortunately, two of the four genes used (namely, c-Myc and KLF4) are oncogenic, and 20% of the chimeric mice developed cancer. In a later study, Yamanaka reported that one can create iPSCs even without c-Myc. The process takes longer and is not as efficient, but the resulting chimeras didn’t develop cancer.
Induced pluripotent cells have been made from adult stomach, liver, skin cells, blood cells, prostate cells and urinary tract cells.
In November 2007, a milestone was achieved by creating iPSCs from adult human cells; two independent research teams’ studies were released one in Science by James Thomson at University of WisconsinMadison and another in Cell by Shinya Yamanaka and colleagues at Kyoto University, Japan. With the same principle used earlier in mouse models, Yamanaka had successfully transformed human fibroblasts into pluripotent stem cells using the same four pivotal genes: Oct3/4, Sox2, Klf4, and c-Myc with a retroviral system. Thomson and colleagues used OCT4, SOX2, NANOG, and a different gene LIN28 using a lentiviral system.
On 8 November 2012, researchers from Austria, Hong Kong and China presented a protocol for generating human iPSCs from exfoliated renal epithelial cells present in urine on Nature Protocols. This method of acquiring donor cells is comparatively less invasive and simple. The team reported the induction procedure to take less time, around 2 weeks for the urinary cell culture and 3 to 4 weeks for the reprogramming; and higher yield, up to 4% using retroviral delivery of exogenous factors. Urinary iPSCs (UiPSCs) were found to show good differentiation potential, and thus represent an alternative choice for producing pluripotent cells from normal individuals or patients with genetic diseases, including those affecting the kidney.
Although the methods pioneered by Yamanaka and others have demonstrated that adult cells can be reprogrammed to iPS cells, there are still challenges associated with this technology:
The table at right summarizes the key strategies and techniques used to develop iPS cells over the past half-decade. Rows of similar colors represents studies that used similar strategies for reprogramming.
One of the main strategies for avoiding problems (1) and (2) has been to use small compounds that can mimic the effects of transcription factors. These molecule compounds can compensate for a reprogramming factor that does not effectively target the genome or fails at reprogramming for another reason; thus they raise reprogramming efficiency. They also avoid the problem of genomic integration, which in some cases contributes to tumor genesis. Key studies using such strategy were conducted in 2008. Melton et al. studied the effects of histone deacetylase (HDAC) inhibitor valproic acid. They found that it increased reprogramming efficiency 100-fold (compared to Yamanakas traditional transcription factor method). The researchers proposed that this compound was mimicking the signaling that is usually caused by the transcription factor c-Myc. A similar type of compensation mechanism was proposed to mimic the effects of Sox2. In 2008, Ding et al. used the inhibition of histone methyl transferase (HMT) with BIX-01294 in combination with the activation of calcium channels in the plasma membrane in order to increase reprogramming efficiency. Deng et al. of Beijing University reported on July 2013 that induced pluripotent stem cells can be created without any genetic modification. They used a cocktail of seven small-molecule compounds including DZNep to induce the mouse somatic cells into stem cells which they called CiPS cells with the efficiency at 0.2% comparable to those using standard iPSC production techniques. The CiPS cells were introduced into developing mouse embryos and were found to contribute to all major cells types, proving its pluripotency.
Ding et al. demonstrated an alternative to transcription factor reprogramming through the use of drug-like chemicals. By studying the MET (mesenchymal-epithelial transition) process in which fibroblasts are pushed to a stem-cell like state, Dings group identified two chemicals ALK5 inhibitor SB431412 and MEK (mitogen-activated protein kinase) inhibitor PD0325901 which was found to increase the efficiency of the classical genetic method by 100 fold. Adding a third compound known to be involved in the cell survival pathway, Thiazovivin further increases the efficiency by 200 fold. Using the combination of these three compounds also decreased the reprogramming process of the human fibroblasts from four weeks to two weeks. 
Another key strategy for avoiding problems such as tumor genesis and low throughput has been to use alternate forms of vectors: adenovirus, plasmids, and naked DNA and/or protein compounds.
In 2008, Hochedlinger et al. used an adenovirus to transport the requisite four transcription factors into the DNA of skin and liver cells of mice, resulting in cells identical to ESCs. The adenovirus is unique from other vectors like viruses and retroviruses because it does not incorporate any of its own genes into the targeted host and avoids the potential for insertional mutagenesis. In 2009, Freed et al. demonstrated successful reprogramming of human fibroblasts to iPS cells. Another advantage of using adenoviruses is that they only need to present for a brief amount of time in order for effective reprogramming to take place.
Also in 2008, Yamanaka et al. found that they could transfer the four necessary genes with a plasmid. The Yamanaka group successfully reprogrammed mouse cells by transfection with two plasmid constructs carrying the reprogramming factors; the first plasmid expressed c-Myc, while the second expressed the other three factors (Oct4, Klf4, and Sox2). Although the plasmid methods avoid viruses, they still require cancer-promoting genes to accomplish reprogramming. The other main issue with these methods is that they tend to be much less efficient compared to retroviral methods. Furthermore, transfected plasmids have been shown to integrate into the host genome and therefore they still pose the risk of insertional mutagenesis. Because non-retroviral approaches have demonstrated such low efficiency levels, researchers have attempted to effectively rescue the technique with what is known as the piggyBac transposon system. The lifecycle of this system is shown below. Several studies have demonstrated that this system can effectively deliver the key reprogramming factors without leaving any footprint mutations in the host cell genome. As demonstrated in the figure, the piggyBac transposon system involves the re-excision of exogenous genes, which eliminates issues like insertional mutagenesis
In January 2014, two articles were published claiming that a type of pluripotent stem cell can be generated by subjecting the cells to certain types of stress (bacterial toxin, a low pH of 5.7, or physical squeezing); the resulting cells were called STAP cells, for stimulus-triggered acquisition of pluripotency.
In light of difficulties that other labs had replicating the results of the surprising study, in March 2014, one of the co-authors has called for the articles to be retracted. On 4 June 2014, the lead author, Obokata agreed to retract both the papers  after she was found to have committed research misconduct as concluded in an investigation by RIKEN on 1 April 2014.
Studies by Blelloch et al. in 2009 demonstrated that expression of ES cell-specific microRNA molecules (such as miR-291, miR-294 and miR-295) enhances the efficiency of induced pluripotency by acting downstream of c-Myc . More recently (in April 2011), Morrisey et al. demonstrated another method using microRNA that improved the efficiency of reprogramming to a rate similar to that demonstrated by Ding. MicroRNAs are short RNA molecules that bind to complementary sequences on messenger RNA and block expression of a gene. Morriseys team worked on microRNAs in lung development, and hypothesized that their microRNAs perhaps blocked expression of repressors of Yamanakas four transcription factors. Possible mechanisms by which microRNAs can induce reprogramming even in the absence of added exogenous transcription factors, and how variations in microRNA expression of iPS cells can predict their differentiation potential discussed by Xichen Bao et al.
The generation of iPS cells is crucially dependent on the genes used for the induction.
Oct-3/4 and certain members of the Sox gene family (Sox1, Sox2, Sox3, and Sox15) have been identified as crucial transcriptional regulators involved in the induction process whose absence makes induction impossible. Additional genes, however, including certain members of the Klf family (Klf1, Klf2, Klf4, and Klf5), the Myc family (c-myc, L-myc, and N-myc), Nanog, and LIN28, have been identified to increase the induction efficiency.
Induced pluripotent stem cells are similar to natural pluripotent stem cells, such as embryonic stem (ES) cells, in many aspects, such as the expression of certain stem cell genes and proteins, chromatin methylation patterns, doubling time, embryoid body formation, teratoma formation, viable chimera formation, and potency and differentiability, but the full extent of their relation to natural pluripotent stem cells is still being assessed.
Gene expression and genome-wide H3K4me3 and H3K27me3 were found to be extremely similar between ES and iPS cells. The generated iPSCs were remarkably similar to naturally isolated pluripotent stem cells (such as mouse and human embryonic stem cells, mESCs and hESCs, respectively) in the following respects, thus confirming the identity, authenticity, and pluripotency of iPSCs to naturally isolated pluripotent stem cells:
Recent achievements and future tasks for safe iPSC-based cell therapy are collected in the review of Okano et al.
The task of producing iPS cells continues to be challenging due to the six problems mentioned above. A key tradeoff to overcome is that between efficiency and genomic integration. Most methods that do not rely on the integration of transgenes are inefficient, while those that do rely on the integration of transgenes face the problems of incomplete reprogramming and tumor genesis, although a vast number of techniques and methods have been attempted. Another large set of strategies is to perform a proteomic characterization of iPS cells. The Wu group at Stanford University has made significant progress with this strategy. Further studies and new strategies should generate optimal solutions to the five main challenges. One approach might attempt to combine the positive attributes of these strategies into an ultimately effective technique for reprogramming cells to iPS cells.
Another approach is the use of iPS cells derived from patients to identify therapeutic drugs able to rescue a phenotype. For instance, iPS cell lines derived from patients affected by ectodermal dysplasia syndrome (EEC), in which the p63 gene is mutated, display abnormal epithelial commitment that could be partially rescued by a small compound
An attractive feature of human iPS cells is the ability to derive them from adult patients to study the cellular basis of human disease. Since iPS cells are self-renewing and pluripotent, they represent a theoretically unlimited source of patient-derived cells which can be turned into any type of cell in the body. This is particularly important because many other types of human cells derived from patients tend to stop growing after a few passages in laboratory culture. iPS cells have been generated for a wide variety of human genetic diseases, including common disorders such as Down syndrome and polycystic kidney disease. In many instances, the patient-derived iPS cells exhibit cellular defects not observed in iPS cells from healthy patients, providing insight into the pathophysiology of the disease. An international collaborated project, StemBANCC, was formed in 2012 to build a collection of iPS cell lines for drug screening for a variety of disease. Managed by the University of Oxford, the effort pooled funds and resources from 10 pharmaceutical companies and 23 universities. The goal is to generate a library of 1,500 iPS cell lines which will be used in early drug testing by providing a simulated human disease environment.
A proof-of-concept of using induced pluripotent stem cells (iPSCs) to generate human organ for transplantation was reported by researchers from Japan. Human liver buds (iPSC-LBs) were grown from a mixture of three different kinds of stem cells: hepatocytes (for liver function) coaxed from iPSCs; endothelial stem cells (to form lining of blood vessels) from umbilical cord blood; and mesenchymal stem cells (to form connective tissue). This new approach allows different cell types to self-organize into a complex organ, mimicking the process in fetal development. After growing in vitro for a few days, the liver buds were transplanted into mice where the liver quickly connected with the host blood vessels and continued to grow. Most importantly, it performed regular liver functions including metabolizing drugs and producing liver-specific proteins. Further studies will monitor the longevity of the transplanted organ in the host body (ability to integrate or avoid rejection) and whether it will transform into tumors. Using this method, cells from one mouse could be used to test 1,000 drug compounds to treat liver disease, and reduce animal use by up to 50,000.
Embryonic cord-blood cells were induced into pluripotent stem cells using plasmid DNA. Using cell surface endothelial/pericytic markers CD31 and CD146, researchers identified ‘vascular progenitor’, the high-quality, multipotent vascular stem cells. After the iPS cells were injected directly into the vitreous of the damaged retina of mice, the stem cells engrafted into the retina, grew and repaired the vascular vessels.
In a study conducted in China in 2013, Superparamagnetic iron oxide (SPIO) particles were used to label iPSCs-derived NSCs in vitro. Labeled NSCs were implanted into TBI rats and SCI monkeys 1 week after injury, and then imaged using gradient reflection echo (GRE) sequence by 3.0T magnetic resonance imaging (MRI) scanner. MRI analysis was performed at 1, 7, 14, 21, and 30 days, respectively, following cell transplantation. Pronounced hypointense signals were initially detected at the cell injection sites in rats and monkeys and were later found to extend progressively to the lesion regions, demonstrating that iPSCs-derived NSCs could migrate to the lesion area from the primary sites. The therapeutic efficacy of iPSCs-derived NSCs was examined concomitantly through functional recovery tests of the animals. In this study, we tracked iPSCs-derived NSCs migration in the CNS of TBI rats and SCI monkeys in vivo for the first time. Functional recovery tests showed obvious motor function improvement in transplanted animals. These data provide the necessary foundation for future clinical application of iPSCs for CNS injury.
In 2014, type O red blood cells were synthesized at the Scottish National Blood Transfusion Service from iPSC. The cells were induced to become a mesoderm and then blood cells and then red blood cells. The final step was to make them eject their nuclei and mature properly. Type O can be transfused into all patients. Each pint of blood contains about two trillion red blood cells, while some 107 million blood donations are collected globally every year. Human transfusions were not expected to begin until 2016.
The first human clinical trial using autologous iPSCs is approved by the Japan Ministry Health and will be conducted in 2014 in Kobe. iPSCs derived from skin cells from six patients suffering from wet age-related macular degeneration will be reprogrammed to differentiate into retinal pigment epithelial (RPE) cells. The cell sheet will be transplanted into the affected retina where the degenerated RPE tissue has been excised. Safety and vision restoration monitoring is expected to last one to three years. The benefits of using autologous iPSCs are that there is theoretically no risk of rejection and it eliminates the need to use embryonic stem cells.
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Founded in 2009 by Nobel prize winner Professor Sir Martin Evans and Ajan Reginald, former Global Head of Emerging Technologies at Roche, CTL develops life-saving and life altering regenerative medicines. CTLs team of scientists, physicians, and experienced management have discovered and developed a pipeline of world-class regenerative medicines.
Sir Martin Evans’ unique expertise in discovering rare stem cells led to CTLs innovative drug discovery engine that can uniquely isolate very rare and potent tissue specific stem cells. This exceptional class of cells is then engineered into unique disease-specific cellular regenerative medicines. Each medicine is disease specific and forms part of CTLs world-class portfolio of four off the shelf blockbuster medicines all scheduled for launch before 2020.
The products in late stage clinical trials include Heartcel which regenerates the damaged heart of adults with coronary artery malformations and children with Kawasaki Disease and Bland White Garland Syndrome. In 2014, Heartcel reported unprecedented heart regeneration clinical trial results and is scheduled to launch in 2018 to treat ~400,000 patients worldwide. Myocardion is in Phase II/III trials and treats mild-moderate heart failure affecting 10 million patients worldwide. Tendoncel is the worlds first topical regenerative medicine, for early intervention of severe tendon injuries, and has completed Phase II trials. It is designed to treat the >1 million severe tendon injuries each year in the US and Europe. Skincel is for skin regeneration, and is due to complete Phase II trials in 2015. It is designed to address ulceration and wrinkles.
CTL combines world-class science and management expertise to bring life-saving regenerative medicines to market.
European Society of Gene and Cell Therapy Congress, 17-20 September 2015, Helsinki,Finland (ESGCT 2015)
4th International Conference and Exhibition on Cell & Gene Therapy, August 10-12, 2015, London (CGT 2015)
The International Society for Stem Cell Research Annual Meeting, 24th-27th June 2015, Stockholm, Sweden (ISSCR 2015)
British Society for Gene and Cell Therapy Annual Conference, 9th-11th June 2015, Strathclyde, Glasgow (BSGCT 2015)
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Cell Therapy Ltd
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A treatment for Cystic Fibrosis. A cure for AIDS. The end of cancer. That’s what the newspapers promised us in the early 1990’s. Gene therapy was the answer to what ailed us. Scientists had at last learned how to insert healthy genes into unhealthy people. And those healthy genes would either replace the bad genes causing diseases like CF, sickle-cell anemia and hemophilia or stimulate the body’s own immune system to rid itself of HIV and some forms of cancer. A decade later, none of these treatments have come to fruition and research into gene therapy has become politically unpopular, making clinical trials hard to approve and research dollars hard to come by. But some researchers who are taking a different approach to gene therapy could be on the road to more success than ever before. – – – – – – – – – – – –
Almost as soon as Watson and Crick unwound the double helix in the 1950’s, researchers began considering the possibility- and ethics- of gene therapy. The goals were lofty- to fix inherited genetic diseases such as Cystic Fibrosis and hemophilia forever.
Gene therapists planned to isolate the relevant gene in question, prepare good copies of that gene, then deliver them to patients’ cells. The hope was that the treated cells would give rise to new generations of healthy cells for the rest of the patient’s life. The concept was elegant, but would require decades of research to locate the genes that cause illnesses.
By 1990, it was working in the lab. By inserting healthy genes into cells from CF patients, scientists were able to transmogrify the sick cells as if by magic into healthy cells.
That same year, four-year-old Ashanti DeSilva became the first person in history to receive gene therapy. Dr. W. French Anderson of the National Heart, Lung and Blood Institute and Dr. Michael Blaese and Dr. Kenneth Culver, both of the National Cancer Institute, performed the historic and controversial experiment.
DeSilva suffered from a rare immune disorder known as ADA deficiency that made her vulnerable to even the mildest infections. A single genetic defect- like a typo in a novel- left DeSilva unable to produce an important enzyme. Without that enzyme, DeSilva was likely to die a premature death.
Anderson, Blaese and Culver drew the girl’s blood and treated her defective white blood cells with the gene she lacked. The altered cells were then injected back into the girl, where- the scientists hoped- they would produce the enzyme she needed as well as produce future generations of normal cells.
Though the treatment proved safe, its efficacy is still in question. The treated cells did produce the enzyme, but failed to give rise to healthy new cells. DeSilva, who is today relatively healthy, still receives periodic gene therapy to maintain the necessary levels of the enzyme in her blood. She also takes doses of the enzyme itself, in the form of a drug called PEG-ADA, which makes it difficult to tell how well the gene therapy would have worked alone.
“It was a very logical approach,” says Dr. Jeffrey Isner, Chief of Vascular Medicine and Cardiovascular Research at St. Elizabeth’s Medical Center in Boston as well as Professor of Medicine at Tufts University School of Medicine. “But in most cases the strategy failed, because the vectors we have today are not ready for prime time.” – – – – – – – – – – – – 4 pages: | 1 | 2 | 3 | 4 |
Photo: Dr. W. French Anderson
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As people age, their hormone levels decline, starting in their twenties and thirties. In addition, toxins and other insults from the environment and food supply are believed to contribute to the development of hormonal imbalances.
Bioidentical hormones are hormones that are identical to those that the body makes on its own. Some are available through regular retail pharmacies. Others are only available through compounding pharmacies. The main advantages of bioidentical hormones are that they are very well tolerated and that they have no side effects when they are properly dosed and integrated in a holistic treatment plan. This cannot be said of non-bioidentical hormones, such as Premarin, PremPro, and Provera, that most physicians prescribe. We should avoid using the term hormones when we refer to these non-bioidentical chemicals. These chemicals have many known side effects, in many cases even at the recommended dosage levels. Most people do not realize that treatment with non-bioidentical chemicals cannot even be monitored properly because physicians and laboratories do not offer testing for drugs like Premarin, PremPro, and Provera. We certainly dont know what the optimal levels of horse estrogens are in human beings!
THE WILEY PROTOCOL
When I first started helping my patients with bioidentical hormone replacement therapy I used non-rhythmic, statically dosed protocols. What this meant in the context of replacement of estrogens and progesterone was that I used the same dosages of estradiol (with or without estriol and estrone) and progesterone for specified number of days in a 28- to 30-day cycle.
In February 2007 I started treating patients with the Wiley Protocol. The Wiley Protocol is different in that the dosing of estradiol and progesterone is not static. Instead, the dosages of estradiol and progesterone change cyclically, following either a womans personal cycle (if she still has a regular menstrual cycle) or the cycle of the moon (lunar cycle) if has stopped having periods or her menstrual cycle is irregular.
In a healthy young woman the levels of estradiol and progesterone are low on day 1 of the cycle. Estradiol levels rise gradually during the follicular phase, peak on day 12, and drop abruptly on day 13. After ovulation and after development of the corpus luteum the progesterone levels start rising on day 14, peak on day 21, and finally decrease gradually over the next 7 days if a woman does not get pregnant. When a woman is on the Wiley Protocol the hormone levels follow the pattern that we see in healthy young women. My patients have responded very well to this protocol, especially in cases where they did not respond to other types of hormone replacement therapy.
The Wiley Protocol has been found to be beneficial for women of all ages who experience signs and symptoms related to disorders of reproductive function. These include women with a diagnosis of PCOS (polycystic ovarian syndrome), endometriosis, uterine fibroids, PMS (premenstrual syndrome), irregular periods, painful periods, heavy periods, infertility, hot flashes, insomnia, and acne.
The main reasons that patients have responded so well is that I carefully monitor my patients signs and symptoms and hormone levels on day 12 and day 21 of the menstrual cycle.
Unlike other methods of bioidentical hormone replacement, women of all ages who follow the Wiley Protocol will have a period every month unless they dont have a uterus. More than 90% of female patients who are bioidentical hormone replacement therapy are on the Wiley Protocol because it results in superior symptom relief and because the cyclical dosing schedule makes sense to them intuitively and physiologically. For postmenopausal women who prefer not to have a menstrual period every month again I offer statically dosed therapy.
The following rhythmic, bioidentical Wiley Protocol hormones are available:
Here is information about the Wiley Protocol Face Creme from the Wiley Protocol website:
Wiley Protocol Face Creme We all yearn for a more youthful appearance and Wiley Protocol Face creme provides this option by replenishing the sub-dermal fat base which plumps up the fine lines that make us look old. There are estrogen receptors everywhere in a womans body, including in her skin. As a woman ages, she begins to lose collagen as the levels of estrogen diminish. Many dermatologists and doctors have noted that even systemic hormone therapy seems to improve the appearance of aging skin. Some studies have shown that estrogen, when applied in a cream penetrates the skin due to its small molecular size, and increases the production of collagen. Applied daily, this creme is non-greasy and absorbs quickly.
To find out more about the Wiley Protocol I recommend the following resources:
OTHER BIOIDENTICAL HORMONES
Often patients are deficient in other hormones, such as thyroid hormone, testosterone, cortisol, DHEA, and growth hormone. I offer bioidentical therapies for these hormonal imbalances as well.
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Hormone Replacement | Fred Bloem, MD Holistic Physician …
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Endogenous cardiac stem cells (eCSCs) are tissue-specific stem progenitor cells harboured within the adult mammalian heart.
They were first discovered in 2003 by Bernardo Nadal-Ginard, Piero Anversa and colleagues  in the adult rat heart and since then have been identified and isolated from mouse, dog, porcine and human hearts.
The adult heart was previously thought to be a post mitotic organ without any regenerative capability. The identification of eCSCs has provided an explanation for the hitherto unexplained existence of a subpopulation of immature cycling myocytes in the adult myocardium. Indeed, recent evidence from a genetic fate-mapping study established that stem cells replenish adult mammalian cardiomyocytes lost by cardiac wear and tear and injury throughout the adult life. Moreover, it is now accepted that myocyte death and myocyte renewal are the two sides of the proverbial coin of cardiac homeostasis in which the eCSCs play a central role. These findings produced a paradigm shift in cardiac biology and opened new opportunities and approaches for future treatment of cardiac diseases by placing the heart squarely amongst other organs with regenerative potential such as the liver, skin, muscle, CNS. However, they have not changed the well-established fact that the working myocardium is mainly constituted of terminally differentiated contractile myocytes. This fact does not exclude, but is it fully compatible with the heart being endowed with a robust intrinsic regenerative capacity which resides in the presence of the eCSCs throughout the individual lifespan.
Briefly, eCSCs have been first identified through the expression of c-kit, the receptor of the stem cell factor and the absence of common hematopoietic markers, like CD45. Afterwards, different membrane markers (Sca-1, Abcg-2, Flk-1) and transcription factors (Isl-1, Nkx2.5, GATA4) have been employed to identify and characterize these cells in the embryonic and adult life. eCSCs are clonogenic, self renewing and multipotent in vitro and in vivo, capable of generating the 3 major cell types of the myocardium: myocytes, smooth muscle and endothelial vascular cells. They express several markers of stemness (i.e. Oct3/4, Bmi-1, Nanog) and have significant regenerative potential in vivo. When cloned in suspension they form cardiospheres, which when cultured in a myogenic differentiation medium, attach and differentiate into beating cardiomyocytes.
In 2012, it was proposed that Isl-1 is not a marker for endogenous cardiac stem cells. That same year, a different group demonstrated that Isl-1 is not restricted to second heart field progenitors in the developing heart, but also labels cardiac neural crest. It has also been reported that Flk-1 is not a specific marker for endogenous and mouse ESC-derived Isl1+ CPCs. While some eCSC discoveries have been brought into question, there has been success with other membrane markers. For instance, it was demonstrated that the combination of Flt1+/Flt4+ membrane markers identifies an Isl1+/Nkx2.5+ cell population in the developing heart. It was also shown that endogenous Flt1+/Flt4+ cells could be expanded in vitro and displayed trilineage differentiation potential. Flt1+/Flt4+ CPCs derived from iPSCs were shown to engraft into the adult myocardium and robustly differentiate into cardiomyocytes with phenotypic and electrophysiologic characteristics of adult cardiomyocytes.
With the myocardium now recognized as a tissue with limited regenerating potential, harbouring eCSCs that can be isolated and amplified in vitro  for regenerative protocols of cell transplantation or stimulated to replicate and differentiate in situ in response to growth factors, it has become reasonable to exploit this endogenous regenerative potential to replace lost/damaged cardiac muscle with autologous functional myocardium.
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Endogenous cardiac stem cell – Wikipedia, the free …
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Hematopoietic stem cell transplantation (HSCT) is the transplantation of multipotent hematopoietic stem cells, usually derived from bone marrow, peripheral blood, or umbilical cord blood. It may be autologous (the patient’s own stem cells are used) or allogeneic (the stem cells come from a donor). It is a medical procedure in the field of hematology, most often performed for patients with certain cancers of the blood or bone marrow, such as multiple myeloma or leukemia. In these cases, the recipient’s immune system is usually destroyed with radiation or chemotherapy before the transplantation. Infection and graft-versus-host disease are major complications of allogeneic HSCT.
Hematopoietic stem cell transplantation remains a dangerous procedure with many possible complications; it is reserved for patients with life-threatening diseases. As survival following the procedure has increased, its use has expanded beyond cancer, such as autoimmune diseases.
Indications for stem cell transplantation are as follows:
Many recipients of HSCTs are multiple myeloma or leukemia patients who would not benefit from prolonged treatment with, or are already resistant to, chemotherapy. Candidates for HSCTs include pediatric cases where the patient has an inborn defect such as severe combined immunodeficiency or congenital neutropenia with defective stem cells, and also children or adults with aplastic anemia who have lost their stem cells after birth. Other conditions treated with stem cell transplants include sickle-cell disease, myelodysplastic syndrome, neuroblastoma, lymphoma, Ewing’s sarcoma, desmoplastic small round cell tumor, chronic granulomatous disease and Hodgkin’s disease. More recently non-myeloablative, “mini transplant(microtransplantation),” procedures have been developed that require smaller doses of preparative chemo and radiation. This has allowed HSCT to be conducted in the elderly and other patients who would otherwise be considered too weak to withstand a conventional treatment regimen.
A total of 50,417 first hematopoietic stem cell transplants were reported as taking place worldwide in 2006, according to a global survey of 1327 centers in 71 countries conducted by the Worldwide Network for Blood and Marrow Transplantation. Of these, 28,901 (57 percent) were autologous and 21,516 (43 percent) were allogeneic (11,928 from family donors and 9,588 from unrelated donors). The main indications for transplant were lymphoproliferative disorders (54.5 percent) and leukemias (33.8 percent), and the majority took place in either Europe (48 percent) or the Americas (36 percent). In 2009, according to the World Marrow Donor Association, stem cell products provided for unrelated transplantation worldwide had increased to 15,399 (3,445 bone marrow donations, 8,162 peripheral blood stem cell donations, and 3,792 cord blood units).
Autologous HSCT requires the extraction (apheresis) of haematopoietic stem cells (HSC) from the patient and storage of the harvested cells in a freezer. The patient is then treated with high-dose chemotherapy with or without radiotherapy with the intention of eradicating the patient’s malignant cell population at the cost of partial or complete bone marrow ablation (destruction of patient’s bone marrow function to grow new blood cells). The patient’s own stored stem cells are then transfused into his/her bloodstream, where they replace destroyed tissue and resume the patient’s normal blood cell production. Autologous transplants have the advantage of lower risk of infection during the immune-compromised portion of the treatment since the recovery of immune function is rapid. Also, the incidence of patients experiencing rejection (graft-versus-host disease) is very rare due to the donor and recipient being the same individual. These advantages have established autologous HSCT as one of the standard second-line treatments for such diseases as lymphoma.
However, for others cancers such as acute myeloid leukemia, the reduced mortality of the autogenous relative to allogeneic HSCT may be outweighed by an increased likelihood of cancer relapse and related mortality, and therefore the allogeneic treatment may be preferred for those conditions. Researchers have conducted small studies using non-myeloablative hematopoietic stem cell transplantation as a possible treatment for type I (insulin dependent) diabetes in children and adults. Results have been promising; however, as of 2009[update] it was premature to speculate whether these experiments will lead to effective treatments for diabetes.
Allogeneics HSCT involves two people: the (healthy) donor and the (patient) recipient. Allogeneic HSC donors must have a tissue (HLA) type that matches the recipient. Matching is performed on the basis of variability at three or more loci of the HLA gene, and a perfect match at these loci is preferred. Even if there is a good match at these critical alleles, the recipient will require immunosuppressive medications to mitigate graft-versus-host disease. Allogeneic transplant donors may be related (usually a closely HLA matched sibling), syngeneic (a monozygotic or ‘identical’ twin of the patient – necessarily extremely rare since few patients have an identical twin, but offering a source of perfectly HLA matched stem cells) or unrelated (donor who is not related and found to have very close degree of HLA matching). Unrelated donors may be found through a registry of bone marrow donors such as the National Marrow Donor Program. People who would like to be tested for a specific family member or friend without joining any of the bone marrow registry data banks may contact a private HLA testing laboratory and be tested with a mouth swab to see if they are a potential match. A “savior sibling” may be intentionally selected by preimplantation genetic diagnosis in order to match a child both regarding HLA type and being free of any obvious inheritable disorder. Allogeneic transplants are also performed using umbilical cord blood as the source of stem cells. In general, by transfusing healthy stem cells to the recipient’s bloodstream to reform a healthy immune system, allogeneic HSCTs appear to improve chances for cure or long-term remission once the immediate transplant-related complications are resolved.
A compatible donor is found by doing additional HLA-testing from the blood of potential donors. The HLA genes fall in two categories (Type I and Type II). In general, mismatches of the Type-I genes (i.e. HLA-A, HLA-B, or HLA-C) increase the risk of graft rejection. A mismatch of an HLA Type II gene (i.e. HLA-DR, or HLA-DQB1) increases the risk of graft-versus-host disease. In addition a genetic mismatch as small as a single DNA base pair is significant so perfect matches require knowledge of the exact DNA sequence of these genes for both donor and recipient. Leading transplant centers currently perform testing for all five of these HLA genes before declaring that a donor and recipient are HLA-identical.
Race and ethnicity are known to play a major role in donor recruitment drives, as members of the same ethnic group are more likely to have matching genes, including the genes for HLA.
As of 2013[update], there were at least two commercialized allogeneic cell therapies, Prochymal and Cartistem.
To limit the risks of transplanted stem cell rejection or of severe graft-versus-host disease in allogeneic HSCT, the donor should preferably have the same human leukocyte antigens (HLA) as the recipient. About 25 to 30 percent of allogeneic HSCT recipients have an HLA-identical sibling. Even so-called “perfect matches” may have mismatched minor alleles that contribute to graft-versus-host disease.
In the case of a bone marrow transplant, the HSC are removed from a large bone of the donor, typically the pelvis, through a large needle that reaches the center of the bone. The technique is referred to as a bone marrow harvest and is performed under general anesthesia.
Peripheral blood stem cells are now the most common source of stem cells for allogeneic HSCT. They are collected from the blood through a process known as apheresis. The donor’s blood is withdrawn through a sterile needle in one arm and passed through a machine that removes white blood cells. The red blood cells are returned to the donor. The peripheral stem cell yield is boosted with daily subcutaneous injections of Granulocyte-colony stimulating factor, serving to mobilize stem cells from the donor’s bone marrow into the peripheral circulation.
It is also possible to extract stem cells from amniotic fluid for both autologous or heterologous use at the time of childbirth.
Umbilical cord blood is obtained when a mother donates her infant’s umbilical cord and placenta after birth. Cord blood has a higher concentration of HSC than is normally found in adult blood. However, the small quantity of blood obtained from an Umbilical Cord (typically about 50 mL) makes it more suitable for transplantation into small children than into adults. Newer techniques using ex-vivo expansion of cord blood units or the use of two cord blood units from different donors allow cord blood transplants to be used in adults.
Cord blood can be harvested from the Umbilical Cord of a child being born after preimplantation genetic diagnosis (PGD) for human leucocyte antigen (HLA) matching (see PGD for HLA matching) in order to donate to an ill sibling requiring HSCT.
Unlike other organs, bone marrow cells can be frozen (cryopreserved) for prolonged periods without damaging too many cells. This is a necessity with autologous HSC because the cells must be harvested from the recipient months in advance of the transplant treatment. In the case of allogeneic transplants, fresh HSC are preferred in order to avoid cell loss that might occur during the freezing and thawing process. Allogeneic cord blood is stored frozen at a cord blood bank because it is only obtainable at the time of childbirth. To cryopreserve HSC, a preservative, DMSO, must be added, and the cells must be cooled very slowly in a controlled-rate freezer to prevent osmotic cellular injury during ice crystal formation. HSC may be stored for years in a cryofreezer, which typically uses liquid nitrogen.
The chemotherapy or irradiation given immediately prior to a transplant is called the conditioning regimen, the purpose of which is to help eradicate the patient’s disease prior to the infusion of HSC and to suppress immune reactions. The bone marrow can be ablated (destroyed) with dose-levels that cause minimal injury to other tissues. In allogeneic transplants a combination of cyclophosphamide with total body irradiation is conventionally employed. This treatment also has an immunosuppressive effect that prevents rejection of the HSC by the recipient’s immune system. The post-transplant prognosis often includes acute and chronic graft-versus-host disease that may be life-threatening. However, in certain leukemias this can coincide with protection against cancer relapse owing to the graft versus tumor effect.Autologous transplants may also use similar conditioning regimens, but many other chemotherapy combinations can be used depending on the type of disease.
A newer treatment approach, non-myeloablative allogeneic transplantation, also termed reduced-intensity conditioning (RIC), uses doses of chemotherapy and radiation too low to eradicate all the bone marrow cells of the recipient.:320321 Instead, non-myeloablative transplants run lower risks of serious infections and transplant-related mortality while relying upon the graft versus tumor effect to resist the inherent increased risk of cancer relapse. Also significantly, while requiring high doses of immunosuppressive agents in the early stages of treatment, these doses are less than for conventional transplants. This leads to a state of mixed chimerism early after transplant where both recipient and donor HSC coexist in the bone marrow space.
Decreasing doses of immunosuppressive therapy then allows donor T-cells to eradicate the remaining recipient HSC and to induce the graft versus tumor effect. This effect is often accompanied by mild graft-versus-host disease, the appearance of which is often a surrogate marker for the emergence of the desirable graft versus tumor effect, and also serves as a signal to establish an appropriate dosage level for sustained treatment with low levels of immunosuppressive agents.
Because of their gentler conditioning regimens, these transplants are associated with a lower risk of transplant-related mortality and therefore allow patients who are considered too high-risk for conventional allogeneic HSCT to undergo potentially curative therapy for their disease. The optimal conditioning strategy for each disease and recipient has not been fully established, but RIC can be used in elderly patients unfit for myeloablative regimens, for whom a higher risk of cancer relapse may be acceptable.
After several weeks of growth in the bone marrow, expansion of HSC and their progeny is sufficient to normalize the blood cell counts and re-initiate the immune system. The offspring of donor-derived hematopoietic stem cells have been documented to populate many different organs of the recipient, including the heart, liver, and muscle, and these cells had been suggested to have the abilities of regenerating injured tissue in these organs. However, recent research has shown that such lineage infidelity does not occur as a normal phenomenon.
HSCT is associated with a high treatment-related mortality in the recipient (1 percent or higher), which limits its use to conditions that are themselves life-threatening. Major complications are veno-occlusive disease, mucositis, infections (sepsis), graft-versus-host disease and the development of new malignancies.
Bone marrow transplantation usually requires that the recipient’s own bone marrow be destroyed (“myeloablation”). Prior to “engraftment” patients may go for several weeks without appreciable numbers of white blood cells to help fight infection. This puts a patient at high risk of infections, sepsis and septic shock, despite prophylactic antibiotics. However, antiviral medications, such as acyclovir and valacyclovir, are quite effective in prevention of HSCT-related outbreak of herpetic infection in seropositive patients. The immunosuppressive agents employed in allogeneic transplants for the prevention or treatment of graft-versus-host disease further increase the risk of opportunistic infection. Immunosuppressive drugs are given for a minimum of 6-months after a transplantation, or much longer if required for the treatment of graft-versus-host disease. Transplant patients lose their acquired immunity, for example immunity to childhood diseases such as measles or polio. For this reason transplant patients must be re-vaccinated with childhood vaccines once they are off immunosuppressive medications.
Severe liver injury can result from hepatic veno-occlusive disease (VOD). Elevated levels of bilirubin, hepatomegaly and fluid retention are clinical hallmarks of this condition. There is now a greater appreciation of the generalized cellular injury and obstruction in hepatic vein sinuses, and hepatic VOD has lately been referred to as sinusoidal obstruction syndrome (SOS). Severe cases of SOS are associated with a high mortality rate. Anticoagulants or defibrotide may be effective in reducing the severity of VOD but may also increase bleeding complications. Ursodiol has been shown to help prevent VOD, presumably by facilitating the flow of bile.
The injury of the mucosal lining of the mouth and throat is a common regimen-related toxicity following ablative HSCT regimens. It is usually not life-threatening but is very painful, and prevents eating and drinking. Mucositis is treated with pain medications plus intravenous infusions to prevent dehydration and malnutrition.
Graft-versus-host disease (GVHD) is an inflammatory disease that is unique to allogeneic transplantation. It is an attack of the “new” bone marrow’s immune cells against the recipient’s tissues. This can occur even if the donor and recipient are HLA-identical because the immune system can still recognize other differences between their tissues. It is aptly named graft-versus-host disease because bone marrow transplantation is the only transplant procedure in which the transplanted cells must accept the body rather than the body accepting the new cells. Acute graft-versus-host disease typically occurs in the first 3 months after transplantation and may involve the skin, intestine, or the liver. High-dose corticosteroids such as prednisone are a standard treatment; however this immuno-suppressive treatment often leads to deadly infections. Chronic graft-versus-host disease may also develop after allogeneic transplant. It is the major source of late treatment-related complications, although it less often results in death. In addition to inflammation, chronic graft-versus-host disease may lead to the development of fibrosis, or scar tissue, similar to scleroderma; it may cause functional disability and require prolonged immunosuppressive therapy. Graft-versus-host disease is usually mediated by T cells, which react to foreign peptides presented on the MHC of the host.
Graft versus tumor effect (GVT) or “graft versus leukemia” effect is the beneficial aspect of the Graft-versus-Host phenomenon. For example, HSCT patients with either acute, or in particular chronic, graft-versus-host disease after an allogeneic transplant tend to have a lower risk of cancer relapse. This is due to a therapeutic immune reaction of the grafted donor T lymphocytes against the diseased bone marrow of the recipient. This lower rate of relapse accounts for the increased success rate of allogeneic transplants, compared to transplants from identical twins, and indicates that allogeneic HSCT is a form of immunotherapy. GVT is the major benefit of transplants that do not employ the highest immuno-suppressive regimens.
Graft versus tumor is mainly beneficial in diseases with slow progress, e.g. chronic leukemia, low-grade lymphoma, and some cases multiple myeloma. However, it is less effective in rapidly growing acute leukemias.
If cancer relapses after HSCT, another transplant can be performed, infusing the patient with a greater quantity of donor white blood cells (Donor lymphocyte infusion).
Patients after HSCT are at a higher risk for oral carcinoma. Post-HSCT oral cancer may have more aggressive behavior with poorer prognosis, when compared to oral cancer in non-HSCT patients.
Prognosis in HSCT varies widely dependent upon disease type, stage, stem cell source, HLA-matched status (for allogeneic HCST) and conditioning regimen. A transplant offers a chance for cure or long-term remission if the inherent complications of graft versus host disease, immuno-suppressive treatments and the spectrum of opportunistic infections can be survived. In recent years, survival rates have been gradually improving across almost all populations and sub-populations receiving transplants.
Mortality for allogeneic stem cell transplantation can be estimated using the prediction model created by Sorror et al., using the Hematopoietic Cell Transplantation-Specific Comorbidity Index (HCT-CI). The HCT-CI was derived and validated by investigators at the Fred Hutchinson Cancer Research Center (Seattle, WA). The HCT-CI modifies and adds to a well-validated comorbidity index, the Charlson Comorbidity Index (CCI) (Charlson et al.) The CCI was previously applied to patients undergoing allogeneic HCT but appears to provide less survival prediction and discrimination than the HCT-CI scoring system.
The risks of a complication depend on patient characteristics, health care providers and the apheresis procedure, and the colony-stimulating factor used (G-CSF). G-CSF drugs include filgrastim (Neupogen, Neulasta), and lenograstim (Graslopin).
Filgrastim is typically dosed in the 10 microgram/kg level for 45 days during the harvesting of stem cells. The documented adverse effects of filgrastim include splenic rupture (indicated by left upper abdominal or shoulder pain, risk 1 in 40000), Adult respiratory distress syndrome (ARDS), alveolar hemorrage, and allergic reactions (usually expressed in first 30 minutes, risk 1 in 300). In addition, platelet and hemoglobin levels dip post-procedure, not returning to normal until one month.
The question of whether geriatrics (patients over 65) react the same as patients under 65 has not been sufficiently examined. Coagulation issues and inflammation of atherosclerotic plaques are known to occur as a result of G-CSF injection. G-CSF has also been described to induce genetic changes in mononuclear cells of normal donors. There is evidence that myelodysplasia (MDS) or acute myeloid leukaemia (AML) can be induced by GCSF in susceptible individuals.
Blood was drawn peripherally in a majority of patients, but a central line to jugular/subclavian/femoral veins may be used in 16 percent of women and 4 percent of men. Adverse reactions during apheresis were experienced in 20 percent of women and 8 percent of men, these adverse events primarily consisted of numbness/tingling, multiple line attempts, and nausea.
A study involving 2408 donors (1860 years) indicated that bone pain (primarily back and hips) as a result of filgrastim treatment is observed in 80 percent of donors by day 4 post-injection. This pain responded to acetaminophen or ibuprofen in 65 percent of donors and was characterized as mild to moderate in 80 percent of donors and severe in 10 percent. Bone pain receded post-donation to 26 percent of patients 2 days post-donation, 6 percent of patients one week post-donation, and
In one metastudy that incorporated data from 377 donors, 44 percent of patients reported having adverse side effects after peripheral blood HSCT. Side effects included pain prior to the collection procedure as a result of GCSF injections, post-procedural generalized skeletal pain, fatigue and reduced energy.
A study that surveyed 2408 donors found that serious adverse events (requiring prolonged hospitalization) occurred in 15 donors (at a rate of 0.6 percent), although none of these events were fatal. Donors were not observed to have higher than normal rates of cancer with up to 48 years of follow up. One study based on a survey of medical teams covered approximately 24,000 peripheral blood HSCT cases between 1993 and 2005, and found a serious cardiovascular adverse reaction rate of about 1 in 1500. This study reported a cardiovascular-related fatality risk within the first 30 days HSCT of about 2 in 10000. For this same group, severe cardiovascular events were observed with a rate of about 1 in 1500. The most common severe adverse reactions were pulmonary edema/deep vein thrombosis, splenic rupture, and myocardial infarction. Haematological malignancy induction was comparable to that observed in the general population, with only 15 reported cases within 4 years.
Georges Math, a French oncologist, performed the first European bone marrow transplant in November 1958 on five Yugoslavian nuclear workers whose own marrow had been damaged by irradiation caused by a criticality accident at the Vina Nuclear Institute, but all of these transplants were rejected. Math later pioneered the use of bone marrow transplants in the treatment of leukemia.
Stem cell transplantation was pioneered using bone-marrow-derived stem cells by a team at the Fred Hutchinson Cancer Research Center from the 1950s through the 1970s led by E. Donnall Thomas, whose work was later recognized with a Nobel Prize in Physiology or Medicine. Thomas’ work showed that bone marrow cells infused intravenously could repopulate the bone marrow and produce new blood cells. His work also reduced the likelihood of developing a life-threatening complication called graft-versus-host disease.
The first physician to perform a successful human bone marrow transplant on a disease other than cancer was Robert A. Good at the University of Minnesota in 1968. In 1975, John Kersey, M.D., also of the University of Minnesota, performed the first successful bone marrow transplant to cure lymphoma. His patient, a 16-year-old-boy, is today the longest-living lymphoma transplant survivor.
At the end of 2012, 20.2 million people had registered their willingness to be a bone marrow donor with one of the 67 registries from 49 countries participating in Bone Marrow Donors Worldwide. 17.9 million of these registered donors had been ABDR typed, allowing easy matching. A further 561,000 cord blood units had been received by one of 46 cord blood banks from 30 countries participating. The highest total number of bone marrow donors registered were those from the USA (8.0 million), and the highest number per capita were those from Cyprus (15.4 percent of the population).
Within the United States, racial minority groups are the least likely to be registered and therefore the least likely to find a potentially life-saving match. In 1990, only six African-Americans were able to find a bone marrow match, and all six had common European genetic signatures.
Africans are more genetically diverse than people of European descent, which means that more registrations are needed to find a match. Bone marrow and cord blood banks exist in South Africa, and a new program is beginning in Nigeria. Many people belonging to different races are requested to donate as there is a shortage of donors in African, Mixed race, Latino, Aboriginal, and many other communities.
In 2007, a team of doctors in Berlin, Germany, including Gero Htter, performed a stem cell transplant for leukemia patient Timothy Ray Brown, who was also HIV-positive. From 60 matching donors, they selected a [CCR5]-32 homozygous individual with two genetic copies of a rare variant of a cell surface receptor. This genetic trait confers resistance to HIV infection by blocking attachment of HIV to the cell. Roughly one in 1000 people of European ancestry have this inherited mutation, but it is rarer in other populations. The transplant was repeated a year later after a leukemia relapse. Over three years after the initial transplant, and despite discontinuing antiretroviral therapy, researchers cannot detect HIV in the transplant recipient’s blood or in various biopsies of his tissues. Levels of HIV-specific antibodies have also declined, leading to speculation that the patient may have been functionally cured of HIV. However, scientists emphasise that this is an unusual case. Potentially fatal transplant complications (the “Berlin patient” suffered from graft-versus-host disease and leukoencephalopathy) mean that the procedure could not be performed in others with HIV, even if sufficient numbers of suitable donors were found.
In 2012, Daniel Kuritzkes reported results of two stem cell transplants in patients with HIV. They did not, however, use donors with the 32 deletion. After their transplant procedures, both were put on antiretroviral therapies, during which neither showed traces of HIV in their blood plasma and purified CD4 T cells using a sensitive culture method (less than 3 copies/mL). However, the virus was once again detected in both patients some time after the discontinuation of therapy.
Since McAllister’s 1997 report on a patient with multiple sclerosis (MS) who received a bone marrow transplant for CML, there have been over 600 reports of HSCTs performed primarily for MS. These have been shown to “reduce or eliminate ongoing clinical relapses, halt further progression, and reduce the burden of disability in some patients” that have aggressive highly active MS, “in the absence of chronic treatment with disease-modifying agents”.
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