New Leukemia Treatment In US begins with stem cell for first clinical trial.
0 ความคิดเห็น ที่ 00:41
Ultimately, the researchers hope the experimental cellular therapy will improve overall survival rates for blood cancer patients as well as offer a potential new paradigm for treating autoimmune diseases.
Image: www.grtl.org
"Toward our quest of making transplants even safer for adults and children with leukemia, lymphoma, multiple myeloma, and other blood and marrow disorders, we are exploring the possibility of using T-regs to enhance the rate of blood and marrow recovery and reduce the risks of graft-versus-host disease, a complication that affects more than 60 percent of patients," said Claudio Brunstein, M.D., principal investigator of the study.
T-regs are a type of lymphocyte, or white blood cell that normally regulates the body's immune responses. In the case of transplant, donor T-regs may suppress the recipient's immune system so that the healthy donor's blood-forming stem cells and immune cells can grow, helping ward off life-threatening graft-versus-host-disease (GVHD). GVHD occurs when the immune cells within the donated cells attack the body of the transplant recipient. GVHD causes one-third of deaths after transplant.
Researchers have proven in animal models that infusing T-regs after transplant increases the chance of blood and marrow recovery and decreases the risk of GVHD.
"Once we identified that T-regs were highly effective in mouse models, we then spent three years finding ways to make this therapy valuable for transplant patients and potentially useful for patients with autoimmune diseases," said Bruce Blazar, M.D., director of the Center for Translational Medicine at the University.
The T-regs in this study are isolated from umbilical cord blood (blood collected from the placenta or afterbirth after the birth of a child) because they occur in higher frequency than what is typically found in most adults and are easier to expand in culture prior to treatment. This is the first human clinical trial in the world that uses T-regs derived from umbilical cord blood.
This trial is designed to find the highest possible safe dose of T-regs in immune suppressed patients undergoing a double umbilical cord blood transplant for leukemia, other blood cancer, or bone marrow failure. From data in animal models, University researchers believe there will be no acute side effects with the T-regs.
If the data in humans mimics animal models, T-regs will be a powerful therapy to prevent GVHD and enhance engraftment in transplant patients. Once safety and efficacy data are known, researchers hope to test T-regs for treatment of various autoimmune diseases, such as type I diabetes and multiple sclerosis. University researchers hypothesize that if T-regs are transplanted early in the life of the disease, the cells may help prevent disease progression.
"This is an exciting time. In the near future, I anticipate being able to combine immune cell populations, like T-regs, that stop immune reactions responsible for autoimmune diseases like diabetes, and immune responses to stem cell infusion given to repair already damaged tissues. This brings great hope not only for adults and children with cancer but many other diseases as well. At the close of this clinical trial, we hope to go right to our first clinical trial with T-regulatory cells in the treatment of newly diagnosed diabetes," said John E. Wagner, M.D., director of the pediatric hematology-oncology and blood and marrow transplantation program at the University of Minnesota.
This study is funded by the National Institutes of Health, the National Cancer Institute, the National Heart Lung and Blood Institute, and National Institute of Allergy and Infectious Diseases, the Leukemia and Lymphoma Society, the National Marrow Donor Program, and the Children's Cancer Research Fund.
Note: This story has been adapted from a news release issued by University of Minnesota.
And the original Article from http://www.sciencedaily.com/
Stem cells have the unique characteristic of "plasticity" -- they have the ability to give rise to all of the different tissues of the human body. In general, stem cells have two distinguishing characteristics: They are unspecialized, in that they can clone themselves without limit; and they can differentiate into many cell types with specific functions.
Recently, scientists have discovered that human adipose (fat) tissue has a higher concentration of adult stem cells than any other tissue in the body. In fact, a given volume of adipose tissue contains 1,000 times more stem cells than the same volume of bone marrow -- 500 mL of fat can yield approximately 200 million stem cells. Stem cells have many unique applications in science and medicine, but this is the first time, protein extract derived from stem cells are used in the field of cosmetic dermatology.
In July 2007, facial and scalp rejuvenate therapies using AAPE was introduced at The Sloane Clinic in Singapore. AAPE (advanced adipose-derived stem cell protein extract) is a mixture of refined growth factor proteins that is extracted from human adipose-derived stem cells. AAPE uses proteins or chemical messengers that are extracted from stem cells found in human fat tissue. These messengers, when deposited or absorbed into the skin or scalp if that were the case, would then send a signal to cells in the skin teaching them to regenerate.
a very simplistic way, we are basically using this product to tell your skin to be young again," says Dr. Low Chai Ling, Aesthetic Physician of The Sloane Clinic, Singapore, one of the first doctors in Singapore to offer this treatment to her patients with overwhelming response.
"These AAPE cells are extracted from human adipocytes (fat cells) during the process of lipoaspiration (fat suction) and they contain the maximal number of stem cells in the human body. By cultivating these regenerative cells in test-tubes, we can establish cell lines which will serve as a reservoir of stem cells for anti-ageing and aesthetic therapies far superior than traditional methods of synthetic chemicals," she added.
Stem Cell as a Therapy
Stem-cell therapy can be viewed as a way to restore embryonic potential to a patient's aged or damaged cells. The goal of stem-cell therapy in aesthetic surgery would be to regenerate aging tissue. (of the face or scalp)
AAPE is the protein messengers extracted from these stem cells, and hence AAPE have the innate ability to rearrange, change, or repair local tissues significantly and rapidly. One of the most promising uses for AAPE may be the regeneration of facial fat that has been lost through the natural aging process -- facial fat atrophy. AAPE to could not only replace lost facial volume, but may also be able to rejuvenate the face by regenerating the skin from the inside out.
AAPE on the scalp can also help with the regeneration of ageing hair follicles and help stimulate hair growth and reverse the effects of balding without the need for hair transplant surgery.
A session will take about 30 minutes with multiple tiny punctures and most will begin to see the effects from your 3rd session onwards. Most patients will do a series of 6 sessions initially to prime their skin for long lasting anti-ageing effects.
"As you know, no treatment is able to freeze time as our bodies and skin is subjected to many environmental assaults daily, but this treatment certainly comes close," says Dr. Low Chai Ling.
Safety and Efficacy
AAPE which is the growth factors derived from stem cells harvested from human fat cells have been certified safe by CTFA (Cosmetic. Toiletry and Fragrance Association) as an approved cosmetic ingredient (Sep/13/2006). It has also been registered with INCI as human adipocyte conditioned media extract. This product is patented. (Patent registration number: PCT/KR2006/004111).
Stem Cell Facial and Scalp Therapy -- Miracle Facial?
Overall, stem cells raise the prospect of regenerating the aging face from the inside out, and thereby have the potential to change the entire practice of facial rejuvenation in the future. Stem Cell Facial Therapy for anti-ageing and intense facial rejuvenation purposes (reduction in wrinkles, pigmentation, evening of skin colour, closure of pores and softening and tightening ) costs around USD$600* per session. Stem Cell Scalp Therapy to regrow hair and reverse balding costs around USD$550*. Hair regrowth is usually seen in 6 sessions, 2 weeks apart.
For most, this is a leap in aesthetic advancement that is going to revolutionalize the cosmetic industry. And this will bring people a step closer to their anti-ageing ideal with the least amount of effort in the long run.
After all, pretty is what you are born with. But beautiful, that's an equal opportunity.
*Prices accurate at time of print but may be subjected to change.
Dr. Low Chai Ling is an aesthetic physician and the medical director of The Sloane Clinic, Singapore.
For more information on this and other treatment, please visit www.sloaneclinic.com
For general enquiries, please email enquiries @sloaneclinic.com
For press and media enquiries, please email marcom @sloaneclinic.com
This original article from: www.prweb.com
The cells from newborn babies can treat leukemia and other diseases of the immune system, but only two percent of the city's 150,000 newborns delivered last year donated umbilical cord blood.
Currently, hospitals don't ask new mothers whether they want to keep, donate or throw away the umbilical cord blood, officials told a science forum on cord blood technology in Shanghai yesterday.
"Twenty-nine states in the United States are making or have made rules on the issue. For instance, doctors in Arizona must ask parents' plans for umbilical cord blood starting this year," said Zheng Bin, an official from Shanghai Cord Blood Bank. "It is a very meaningful method to promote the awareness of cord blood use."
According to him, the bank only collected 3,000 samples for private storage or donation in 2006.
So far, the bank has established links with some 30 local hospitals offering maternity services to provide information on cord blood storage and donation.
"Less than 40 percent of pregnant women have heard of umbilical cord blood," Zheng said. "Even many doctors or health officials are ignorant on the issue."
According to experts, cord blood and bone marrow transplants are used in similar ways. The key ingredient in both is stem cells that give rise to all other cells in the body, including blood and immune cells.
But stem cells in cord blood are less mature than those in adult bone marrow, so there is less rejection by the recipient.
"The chances of finding an acceptable matching donor for a patient is 50 to 100 times higher with umbilical cord blood compared to bone marrow," said Gao Feng, a member of an expert panel on cord blood under the Ministry of Health.
About 40,000 to 50,000 Chinese are diagnosed with leukemia every year. Only one percent of patients are able to receive a stem cell transplant because of the difficulty of finding a matching donor.
"Cord blood is an important alternative for patients to find a matched sample," said Zheng. "Researchers are using stem cells to treat leukemia, spinal injuries and cardiac muscle injuries. In Japan, half of patients get samples from the cord blood bank and half get donations from a bone marrow bank."
Embryonic stem cells treated with growth factor reverse hemophilia in mice
Mouse embryonic stem cells treated in culture with a growth factor and then injected into the liver reverse a form of hemophilia in mice analogous to hemophilia B in humans, the new study shows. A report of the study appears in the journal Proceedings of the National Academy of Sciences today (Feb. 15).
The genetically altered mice lack the clotting substance factor IX, which in humans results in the hereditary bleeding disorder known as hemophilia B. This disease, much less common than hemophilia A, affects roughly one of every 35,000 people, primarily males.
Although embryonic stem, or ES, cells can differentiate into most cell types in the body, numerous problems have arisen in translating their potential into therapeutic strategies, the UNC School of Medicine study authors reported.
These problems include poor engraftment, limited function, rejection of engrafted cells by the immune system and teratomas, tumors involving a mixture of tissue not normally found at that site.
The new study used a line of mouse ES cells developed in the laboratory of senior co-author Dr. Oliver Smithies, Excellence professor of pathology and laboratory medicine at UNC.
A member of the National Academy of Sciences, Smithies has won many honors for gene targeting, a technique he pioneered. This technique allows for the development of mice with specific genetic mutations that mimic human illnesses such as hemophilia. In 2001, Smithies received the Albert Lasker Award for Basic Medical Research, often called "America's Nobel."
In the study, ES cells were treated with fibroblast growth factor for seven days prior to injection. As expected, this resulted in ES cells differentiating into early endoderm like precursors, which the researchers named "putative endoderm precursors," or PEPs. Endoderm refers to the inner layer of early embryonic cells that develops into the digestive and respiratory systems.
"Not only do ES cells differentiate into PEPs, they also engraft, persist, differentiate further and then function following injection, resulting in the persistent production of factor IX protein that can only come from a hepatocyte (liver cell) and hemophilia reversal," said study lead author Dr. Jeffrey H. Fair, associate professor of surgery and division chief of abdominal transplant surgery.
Moreover, he said, the PEP cells robustly engraft within the liver and were not recognized by the immune system as foreign.
"Within a few weeks, PEPs became hepatocytes," Fair added. "They went from something that is a very early grandparent of the hepatocyte to becoming hepatocytes. After 115 days, nearly four months after injection, mice still produced factor IX without immune suppression. This occurred even in mice that were a complete immunologic tissue mismatch to the PEPs. In addition, the incidence of teratomas was low."
The researchers believe this study demonstrates the power of multidisciplinary collaboration, said co-lead author Dr. Bruce A. Cairns, assistant professor of surgery and director of research in the N.C. Jaycee Burn Center. "This approach may not only be beneficial, but required in order to solve complex problems such as these in medicine."
Although a number of questions need to be answered, this work has great potential for future applications, not only as a novel therapeutic possibility for hemophilia but also for other genetic or acquired diseases of the liver, said senior co-author Dr. Jeffery A. Frelinger, Kenan professor and chairman of microbiology and immunology.
"The data published in this study shows that embryonic stem cells partially differentiated, are able to remain in the liver and be functional without apparent immunological rejection. This transforms them into possible candidates for cellular transplantation into the liver."
Along with Fair, Cairns, Smithies and Frelinger, co-authors from the department of surgery are Dr. Michael A. LaPaglia, Dr. Montserrat Caballero, Dr. Anthony A. Meyer (chairman) and W. Andrew Pleasant. From the department of pathology and laboratory medicine are Drs. Seigo Hatada and Hyung-suk Kim. From the College of Arts and Sciences' department of biology are Drs. Tong Gui and Darrel W. Stafford; and from the department of genetics, Dr. Larysa Pevny.
The research was supported by grants from the National Institutes of Health and the N.C. Jaycee Burn Center.
American Association for the Advancement of Science
The embargo on this press release has been lifted ahead of schedule.
SEATTLE, WA--New research - published by Science Magazine within the Science Express Web site and released today at the 2004 AAAS Annual Meeting -- may be a first step toward methods for treating diabetes, osteoarthritis, Parkinson's and other diseases, by producing replacement cells unlikely to trigger immune-system rejection.
Transplantation medicine based on stem cells remains a distant hope for now, Science editors cautioned. But, the Science study describes intriguing early results:
For the first time, researchers have reported the development of versatile 'pluripotent' human embryonic stem cells, potentially capable of becoming any cell in the body, from a cloned human blastocyst.
The stem cells were harvested from a blastocyst produced by transferring the nucleus of a non-reproductive ('somatic') cell, containing a woman's genetic blueprint, into a nucleus-free egg from the same donor.
Following this transfer, factors within the host egg's exterior, or cytoplasm, reprogrammed its new nuclear contents by activating versatile embryonic genes, while silencing the more limited adult somatic cell genes. Researchers were then able to collect embryonic stem cells from the resulting cell mass inside the cloned blastocysts.
In theory: 'Because these cells carry the nuclear genome of the individual, after differentiation they could be expected to be transplanted without immune rejection for treatment of degenerative disorders,' reported Woo Suk Hwang of Seoul National University in Korea.
'Our approach opens the door for the use of these specially developed cells in transplantation medicine.'
Embryonic stem cells have previously been produced with cells from mice using the same method, called 'somatic cell nuclear transfer.' But, achieving this trick with human cells posed unique challenges, said Donald Kennedy, Science's Editor-in-Chief.
The researchers attribute their apparent success to the use of extremely fresh donor eggs, stringent timing protocols, and a special method for gently extruding rather than suctioning the DNA-spindle complex from eggs. Suctioning the DNA may damage spindles, possibly causing chromosomal defects called aneuploidy, they noted.
Hwang and colleagues developed the stem cell line, SCNT-hES-1, after collecting 242 eggs from 16 unpaid volunteers who had signed informed-consent agreements. From these eggs, scientists then cultured 30 blastocysts to obtain 20 suitable inner cell masses. By tweaking the amount of time that elapsed between the transfer of the nucleus and the activation of the newly transplanted genetic material, the team was able to optimize their results:
A two-hour delay seemed to work best, so that 20 percent of all reconstructed eggs formed blastocysts. From the inner cell mass of these blastocysts, a single human embryonic stem cell line was obtained.
The resulting stem cells differentiated into all three of the main tissue types that appear at the beginning stages of development, researchers reported. When transplanted into mice, the stem cells differentiated into still more specific cell types, offering further proof of pluripotency.
Interestingly, the research team harvested eggs as well as somatic cells from the same donors: Nuclear material from the somatic cell was transferred into the nucleus-free or enucleated egg of the same woman.
This unusual experimental design may be more effective than person-to-person transfers because it offered greater compatibility between the genetic components that were fused together.
But, were the stem cells truly derived from the transferred nucleus, or were they the result of an accidental 'parthenote'--an artificially induced blastocyst resulting from an egg that began to spontaneously divide?
To support their claim that the resulting stem cells came from the transplanted nucleus, Hwang's team completed DNA fingerprinting analysis, and also checked the expression of imprinted genes.
The results were consistent with stem cells resulting from transplantation.
Many questions remain, Science's Donald Kennedy said: 'The potential for embryonic stem cells is enormous, but researchers still must overcome significant scientific hurdles,' Kennedy remarked.
'These results seem promising. But, it's important to remember that cell and tissue transplantation and gene therapy are still emerging technologies, and it may be years yet before embryonic stem cells can be used in transplantation medicine.'
The research also raises policy and ethical questions, Kennedy noted, since blastocyst-derived stem cells for tissue repair or transplantation might exacerbate pressures on egg donors in some regions.
The prospect of using cloned human blastocysts to produce new embryonic stem cells lines also is likely to provoke further controversy, he added. 'There is widespread consensus among all responsible, mainstream scientists--including the authors of this paper and AAAS, publisher of Science Magazine--that any attempt to clone a human being would be highly dangerous and wrong, and therefore, all reproductive cloning should be banned,' Kennedy said.
'But, the generation of stem cells by somatic cell nuclear transfer methods involving the same individuals may hold promise for advances in transplantation technology that could help people affected by many devastating conditions.'
In addition to Hwang, authors on this Science paper were Young June Ryu, Eul Soon Park, Eu Gene Lee, Hyun Yong Chun, Byeong Chun Lee, Sung Keun Kang, Curie Ahn and Shin Yong Moon, all of Seoul National University; as well as Jong Hyuk Park and Sun Jong Kim of Mizmedi Hospital in Seoul; Ja Min Koo of Gachon Medical School; Jung Hye Hwang of Hanyang University; Ky Young Park of Sunchon National University; and Jose B. Cibelli of Michigan State University.
The American Association for the Advancement of Science (AAAS) is the world's largest general scientific society, and publisher of the journal, Science (www.sciencemag.org). AAAS was founded in 1848, and reports some 265 affiliated societies and academies of science, serving 10 million individuals. Science has the largest paid circulation of any peer-reviewed general science journal in the world, with an estimated total readership of one million. The non-profit AAAS (www.aaas.org) is open to all and fulfills its mission to 'advance science and serve society' through initiatives in science policy; international programs; science education; and more. For the latest research news, log onto EurekAlert!, www.eurekalert.org, the premier science-news Web site, a service of AAAS.
MEDIA NOTE: A newsbriefing on this research will take place at 11:00 a.m. Pacific Time, Thursday, 12 February, during the AAAS Annual Meeting in Seattle, in the Eliza Amphitheater, Grand Hyatt. Further, these and other speakers will take part in a symposium titled, 'Stem Cell Science in the Service of Society,' at 2:30 p.m. Monday, 16 February, Sheraton Hotel, Second Floor, Grand Ballroom C. Press registration is in the AAAS Press Center in Leonesa I of the Grand Hyatt Hotel.
AAAS is the world's largest general scientific society, dedicated to 'Advancing science � Serving society.'
Contact: Ginger Pinholster
gpinhols@aaas.org
206-774-6330
Embryonic stem cells (ESCs) have huge potential use for scientists because they have the ability to turn into many different forms of tissue. However, their use remains highly controversial.
Britain has allowed scientists to conduct embryonic stem cell experiments, but they could soon be banned by the European Union, and the US is still considering the issue.
New Scientist magazine reports that the US team harvested cells from human embryos at an early stage of development.
They then manipulated them in the laboratory to turn them into specialised cells that form myelin, the insulating layer than surrounds nerve fibres.
These cells were transplanted into paralysed rats with bruised spines.
After nine weeks, the rats fully regained the ability to walk.
Analysis of the rats' spinal cords showed that the cells had wrapped themselves around nerve cells and formed new myelin sheaths.
They also secreted substances that appeared to have stimulated the formation of new nerves.
Recent injuries
Dr Hans Keirstead and his team from the University of California at Irvine now plan to use the same technique to treat human patients who have sustained recent spinal cord injuries.
However, treating people who have been paralysed for years or suffer from degenerative nerve diseases will be far more difficult.
Scientists have tried using adult stem cells derived from bone marrow and nerve cells repair damaged spines.
But Thomas Okarma, of US biotech company Geron Corporation which funded the new research, believes only ESCs stand a real chance of success.
They are more versatile than adult stem cells, and, unlike them, can be mass-produced.
Mr Okarma said: 'At this moment, there is very little hard evidence that a bone marrow stem cell can turn into anything but blood or that a skin stem cell can become anything but skin.
Potential treatments
Brain damage
Stroke and traumatic brain injury lead to cell death characterized by a loss of neurons and oligodendrocytes within the brain. Healthy adult brains contain neural stem cells that divide, and act to maintain stem cells numbers or become progenitor cells. In healthy adult animals, progenitor cells migrate within the brain and function primarily to maintain neuron populations for olfaction (the sense of smell). Interestingly, in pregnancy and after injury this system appears to be regulated by growth factors and can increase the rate at which new brain matter is formed. In the case of brain injury, although the reparative process appears to initiate, substantial recovery is rarely observed in adults suggesting a lack of robustness. Recently, results from research conducted in rats subjected to stroke suggested that administration of drugs to increase the stem cell division rate and direct the survival and differentiation of newly formed cells could be successful. In the study referenced below, biological drugs were administered after stroke to activate two key steps in the reparative process. Findings from this study seem to support a new strategy for the treatment of stroke using a simple elegant approach aimed at directing recovery from stroke by potentially protecting and/or regenerating new tissue. The authors found that, within weeks, recovery of brain structure is accompanied by recovery of lost limb function suggesting the potential for development of a new class of stroke therapy or brain injury therapy in humans.
Cancer
Research injecting neural (adult) stem cells into the brains of dogs can be very successful in treating cancerous tumors. With traditional techniques brain cancer is almost impossible to treat because it spreads so rapidly. Researchers at the Harvard Medical School caused intracranial tumours in rodents. Then, they injected human neural stem cells. Within days the cells had migrated into the cancerous area and produced cytosine deaminase, an enzyme that converts a non-toxic pro-drug into a chemotheraputic agent. As a result, the injected substance was able to reduce tumor mass by 80 percent. The stem cells neither differentiated nor turned tumorigenic.
Spinal cord injury
A team of Korean researchers reported on November 25, 2004, that they had transplanted multipotent adult stem cells from umbilical cord blood to a patient suffering from a spinal cord injury and she can now walk on her own, without difficulty. The patient had not been able stand up for the last 19 years. The team was co-headed by researchers at Chosun University, Seoul National University and the Seoul Cord Blood Bank (SCB). For the unprecedented clinical test, the scientists isolated adult stem cells from umbilical cord blood and then injected them into the damaged part of the spinal cord.
The Korean researchers have followed up on their original work. The original treatment was conducted in November 2004. On April 18, 2005, the researchers announced that they will be conducting a second treatment on the woman.[6] The researchers have followed up with a case study write-up on their work. It is located in the journal Cytotherapy.[7]
According to the October 7, 2005 issue of The Week, University of California researchers injected human embryonic stem cells into paralyzed mice, which resulted in the mice regaining the ability to move and walk four months later. The researchers discovered upon dissecting the mice that the stem cells regenerated not only the neurons, but also the cells of the myelin sheath, a layer of cells which insulates neural impulses and speeds them up, facilitating communication with the brain (damage to which is often the cause of neurological injury in humans).
In January 2005, researchers at the University of Wisconsin-Madison differentiated human blastocyst stem cells into neural stem cells, then into the beginnings of motor neurons, and finally into spinal motor neuron cells, the cell type that, in the human body, transmits messages from the brain to the spinal cord. The newly generated motor neurons exhibited electrical activity, the signature action of neurons. Lead researcher Su-Chun Zhang described the process as "you need to teach the blastocyst stem cells to change step by step, where each step has different conditions and a strict window of time."
Transforming blastocyst stem cells into motor neurons had eluded researchers for decades. The next step will be to test if the newly generated neurons can communicate with other cells when transplanted into a living animal; the first test will be in chicken embryos. Su-Chun said their trial-and-error study helped them learn how motor neuron cells, which are key to the nervous system, develop in the first place. The new cells could be used to treat diseases like Lou Gehrig's disease, muscular dystrophy, and spinal cord injuries.
Heart damage
Several clinical trials targeting heart disease have shown that adult stem cell therapy is safe. However, none of these trials have proven efficacy. Adult stem cell therapy for heart disease is commercially available. Patients such as the late Jeannine Lewis, who died less than one year after treatment, [9] and the late Hawaiian crooner Don Ho, who died within 15 months of treatment, [10] have traveled to Thailand to receive stem cell therapy for their heart disease.
Using the patient's own bone marrow derived stem cells, Dr. Amit Patel at the University of Pittsburgh, McGowan Institute of Regenerative Medicine has shown a dramatic increase in ejection fraction for patients with congestive heart failure. He has worked with many other countries such as Argentina, Uruguay, Ecuador, Greece, Japan, and Thailand where he has taught minimally invasive techniques for the treatment of non-ischemic (idiopathic) and ischemic heart failure.
A Brazilian stem cell bank, has performed sample manipulation in more than 30 cell therapy procedures in cardiac patients.
Haematopoiesis (blood cell formation)
In December 2004, a team of researchers led by Dr. Luc Douay at the University of Paris developed a method to produce large numbers of red blood cells. The Nature Biotechnology paper, entitled Ex vivo generation of fully mature human red blood cells, describes the process: precursor red blood cells, called hematopoietic stem cells, are grown together with stromal cells, creating an environment that mimics the conditions of bone marrow, the natural site of red blood cell growth. Erythropoietin, a growth factor, is added, coaxing the stem cells to complete terminal differentiation into red blood cells.
Further research into this technique will have potential benefits to gene therapy, blood transfusion, and topical medicine.
Baldness
Hair follicles also contain stem cells, and some researchers predict research on these follicle stem cells may lead to successes in treating baldness through "hair multiplication", also known as "hair cloning", as early as 2007. This treatment is expected to work through taking stem cells from existing follicles, multiplying them in cultures, and implanting the new follicles into the scalp. Later treatments may be able to simply signal follicle stem cells to give off chemical signals to nearby follicle cells which have shrunk during the aging process, which in turn respond to these signals by regenerating and once again making healthy hair. Hair Cloning Nears Reality as Baldness Cure (WebMD November 2004)
Missing teeth
In 2004, scientists at King's College London discovered a way to cultivate a complete tooth in mice and were able to grow them stand-alone in the laboratory. Researchers are confident that this technology can be used to grow live teeth in human patients.
In theory, stem cells taken from the patient could be coaxed in the lab into turning into a tooth bud which, when implanted in the gums, will give rise to a new tooth, which would be expected to take two months to grow. It will fuse with the jawbone and release chemicals that encourage nerves and blood vessels to connect with it. The process is similar to what happens when humans grow their original adult teeth.
It's estimated that it may take until 2009 before the technology is widely available to the general public, but the genetic research scientist behind the technique, Professor Paul Sharpe of King's College, estimates the method could be ready to test on patients by 2007.[13] His startup company, Odontis, fully expects to offer tooth replacement therapy by the end of the decade.
In 2005, Cryopraxis a stem cell bank in Brazil, collected baby tooth stem cells and harvested different types of differentiated cell types including neurons. This technology may one day make baby tooth a good source of stem cells.
In the next three years, Paul Sharpe hopes to identify more-accessible stem cells that may be able to form not only teeth, but also--and more importantly--roots.[14]
Deafness
There has been success in regrowing cochlea hair cells with the use of stem cells.[15]
Blindness and vision impairment
Since 2003, researchers have successfully transplanted retinal stem cells into damaged eyes to restore vision. Using embryonic stem cells, scientists are able to grow a thin sheet of totipotent stem cells in the laboratory. When these sheets are transplanted over the damaged retina, the stem cells stimulate renewed repair, eventually restoring vision.[16] The latest such development was in June 2005, when researchers at the Queen Victoria Hospital of Sussex, England were able to restore the sight of forty patients using the same technique. The group, led by Dr. Sheraz Daya, was able to successfully use adult stem cells obtained from the patient, a relative, or even a cadaver. Further rounds of trials are ongoing.[17]
In April 2005, doctors in the UK transplanted corneal stem cells from an organ donor to the cornea of Deborah Catlyn, a woman who was blinded in one eye when an acid was thrown in her eye at a nightclub. The cornea, which is the transparent window of the eye, is a particularly suitable site for transplants. In fact, the first successful human transplant was carried out in 1905 on a cornea by Dr. Eduard Zirm. The recipient was Alois Gloger, a labourer who had been blinded in an accident. The cornea has the remarkable property that it does not contain any blood vessels, making it relatively easy to transplant. The majority of corneal transplants carried out today are due to a degenerative disease called keratoconus which causes vision imapairment and has no known cure even after corneal transplant. It is hoped that stem cell research will one day provide a cure to such debilitating corneal disorders.
As more research yields increasingly precise techniques, stem cell transplantation to restore vision may become viable on a large scale. The success rate of the procedure is currently from 20 to 70 percent,[18] and further stem cell research is required.
ALS (Lou Gehrig's Disease)
In the April 4, 2001 edition of JAMA (Vol. 285, 1691-1693),[19] Drs. Gearhart and Kerr of Johns Hopkins University used stem cells to cure rats of an ALS-like disease. The rats were injected with a virus to kill the spinal cord motor nerves related to leg movement. Dr. Gearhart and Dr. Kerr then injected the spinal cords of the rats with stem cells. These migrated to the sites of injury where they were able to regenerate the dead nerve cells restoring the rats which were once again able to walk.
Current treatments
For over 30 years, bone marrow and more recently umbilical cord blood stem cells have been used to treat cancer patients with conditions such as leukemia and lymphoma. During chemotherapy, most growing cells are killed by the cytotoxic agents. These agents not only kill the leukemia or neoplastic cells, but also those which release the stem cells from the bone marrow. It is this unfortunate side effect of the chemotherapy that the Stem Cell Transplant attempts to reverse; by introducing a Donor's healthy Stem Cells the damaged or destroyed Blood Producing Cells of the patient are replaced. In all current Stem Cell treatments obtaining Stem Cells from a matched Donor is preferable to using the patients own. If (always as a last resort and usually because no matched Donor can be found) it is deemed necessary for the patients own stem cells to be used and the patient has not stored their own collection of stem cells (umbilical cord blood), bone marrow samples must therefore be removed before chemotherapy, and are re-injected afterwards.
Stem cell treatments
Medical researchers believe that stem cell therapy has the potential to radically change the treatment of human disease. A number of adult stem cell therapies already exist, particularly bone marrow transplants that are used to treat leukemia.[25] In the future, medical researchers anticipate being able to use technologies derived from stem cell research to treat a wider variety of diseases including cancer, parkinson's disease, spinal cord injuries, and muscle damage, amongst a number of other impairments and conditions.[26][27] However, there still exists a great deal of social and scientific uncertainty surrounding stem cell research, which could possibly be overcome through public debate and future research.
Stem cells, however, are already used extensively in research, and some scientists do not see cell therapy as the first goal of the research, but see the investigation of stem cells as a goal worthy in itself
