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Posts Tagged ‘Induced pluripotent stem cell’

Parkinson’s patients fund their own stem cell research

In BUSINESS OF STEM CELLS, SCIENCE & STEM CELLS, STEM CELLS IN THE NEWS on March 19, 2013 at 9:00 am

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Healing Parkinson’s patients with their own stem cells

Up to 1 million Americans have Parkinson’s, according to the Parkinson’s Disease Foundation. Because aging is the chief risk factor for the disease, the patient population is expected to increase as the baby boom generation gets older.  Parkinson’s selectively kills brain cells that make the neurotransmitter dopamine, which enables movement. No one knows how it happens, or how to stop it. Researchers expect that transplanted dopamine-producing brain cells will eventually die, but perhaps not for 10 to 15 years.

The most visible symptoms of Parkinson’s include tremors, slowed movement, stooped posture and loss of balance, and trouble speaking. People sometimes walk with a shuffling gait, and they may experience severe and chronic pain. Patients’ faces can assume a mask-like expression.  Drugs that provide dopamine or mimic its effects can partially relieve the symptoms, but they produce side effects such as uncontrolled movement. Also, their effectiveness decreases over time.

A groundbreaking stem cell treatment for Parkinson’s disease is getting close to moving from lab research in La Jolla to therapy for patients. The research, funded by the patients and their supporters, could also pioneer a new model for moving medical advances from the lab into the clinic.

Eight Parkinson’s patients have allied with scientists from The Scripps Research Institute and medical professionals from Scripps Clinic for the project, which involves creating new brain cells from other cells in their own bodies. Because of the unusual, personalized nature of the research, the patients are participating with scientists and doctors as equals, meeting regularly to review the progress.

The ambitious goal is to relieve the movement difficulties Parkinson’s causes by replacing the brain cells the disease destroys. In theory, it would restore near-normal movement for a decade or more, and the procedure could be repeated as needed.

Research is far enough along that scientists and health care professionals in the project are talking to regulators about beginning clinical trials, perhaps as soon as next year.

The replacement brain cells are now being grown in a lab at The Scripps Research Institute. Patches of skin the diameter of a pencil eraser were removed from the patients’ arms and turned into a new kind of stem cell that acts like embryonic stem cells. Called induced pluripotent stem cells, they were discovered in 2006, a feat honored by a Nobel Prize last year.

These IPS cells can become nearly any kind of cell in the body… Another potential advantage of IPS cells over embryonic stem cells is that they should be less prone to rejection by the patients’ immune systems, because the transplanted cells come from the individuals themselves.

Patient Cassandra Peters, 57, learned of the reality of Parkinson’s and the hope of a new treatment in a visit with Dr. Houser, her neurologist.  “Interestingly, when I first had a conversation with her, when she definitively told me I had Parkinson’s, she said to me, quote, “You will have a stem cell procedure in your lifetime.”  I took that ball and held it in my heart, thinking, this is going to be my ‘get out of jail free’ card.  Not a day goes by when I don’t have an opportunity to share what I’m going through now and what the future might hold,” Peters said.

Ileana Slavin, a research associate in the lab of Jeanne Loring, and Suzanne Peterson, a staff scientist, discuss what it means for scientists to directly meet the people they’re trying to help.  Diabetes researcher Matthias von Herrath of the La Jolla Institute for Allergy & Immunology said the work could help scientists developing stem cell therapies for diabetics,” von Herrath said. “And that’s going to open the door for these type of stem cells.”

Loring’s researchers are reaching the final stages of their part of the project. They have made induced pluripotent stem cells from all eight patients, and have turned those into the needed brain cells for two of them. The work continues for the other six.

Parkinson’s represents the “low-hanging fruit” of neurological diseases for stem cell therapy.  We know what cell types are lost in Parkinson’s disease,” Bratt-Leal said in a March 8 meeting of the group. “We can make them from stem cells.  And now we can make stem cells from adult tissues.  The next logical step is to make these cells from people and put them back into them.”

“With IPS cells grown from the patient, rejection should be less of a worry”, Bratt-Leal said.

Now that the research side of the project has overcome its greatest hurdles, the focus is shifting to medicine, Loring said. The replacement brain cells will be grown in a clinical grade facility at the City of Hope in Los Angeles.  As part of the transition to the medical side, Houser will provide expertise in setting up the clinical trial, assuming approval is granted by the U.S. Food and Drug Administration.

Beyond the potential benefit to the eight patients, the project may provide an answer to what Loring and other researchers call the “Valley of Death,” the period that halts promising research before it can become a medical treatment.  Most scientific research is federally funded, but commercialization is left to the private sector. If companies don’t see a way to make money, they won’t pursue a therapy, even if it works.  This problem is especially forbidding for treatments customized to individual patients. These don’t produce economies of scale, and hence are not attractive to pharmaceutical companies.  Advocates of the customized Parkinson’s therapy said it will pay off in the long run. Patients will require less medical care, and find it easier to maintain their jobs.

To Read Full Article click HERE.

MUSCLE REPAIR THROUGH STEM CELLS

In SCIENCE & STEM CELLS, STEM CELLS IN THE NEWS on March 13, 2013 at 9:00 am

Researchers from the University of Minnesota Use Genetically Corrected Stem Cells To Repair Muscles

University of Minnesota researchers from the Lillehei Heart Institute have combined genetic engineering techniques to repair mutations in abnormal muscle cells with cellular reprogramming to generate stem cells that can repair and regenerate muscle regeneration in a mouse model for Duchenne Muscular Dystrophy (DMD). This research is a proof-of-principle experiment that determines the feasibility of combining induced pluripotent stem cell technology and genetic engineering techniques that correct mutations to treat muscular dystrophy. Experimental strategies such as these could represent a major step forward in autologous cell-based therapies for DMD. Furthermore, it might pave the way for clinical trials to test this approach in reprogrammed human pluripotent cells from muscular dystrophy patients.

University of Minnesota researchers combined three groundbreaking technologies to achieve effective muscular dystrophy therapy in a mouse model of DMD. First, researchers reprogrammed skin cells into induced pluripotent stem cells (iPSCs). iPSCs are capable of differentiating into any of the mature cell types within an adult organism. In this case, the University of Minnesota researchers generated pluripotent cells from the skin of mice that carry mutations in two genes; the dystrophin and utrophin genes. Mice with mutations in both the dystrophin and utrophin genes develop a severe case of muscular dystrophy that resembles the type of disease observed in human DMD patients. This provided a model system platform that successfully mimicked what would theoretically occur in humans.

The second technology employed is a genetic correction tool developed at the University of Minnesota. In this case, they used a transposon, which is a segment of DNA that can jump from one location to another within the genome. The specific transposon used is the “Sleeping Beauty Transposon.” The use of this transposon allowed them to transport genes into cells in a convenient manner. The Lillehei Heart Institute researchers used the Sleeping Beauty transposon to deliver a gene called “micro-utrophin” into the iPSCs made from the DMD mice.

Sleeping Beauty Transposon

Human micro-utrophin can support muscle fiber strength and prevent muscle fiber injury throughout the body. However, there is one essential difference micro-utrophin and dystrophin: dystrophin is absent in muscular dystrophy patients, but if it is introduced into the bodies of DMD patients, their immune system will initiate a devastating immune response against it. However, in those same patients, utrophin is active and functional, which makes it essentially “invisible” to the immune system. This invisibility allows the micro-utrophin to replace dystrophin build and repair muscle fibers within the body.

Utrophin

The third technology utilized is a method to produce skeletal muscle stem cells from pluripotent cells. This procedure was developed in the laboratory of Rita Perlingeiro, who is also the principal investigator of this latest study.

Perlingeiro’s technology gives pluripotent cells a short pulse of a muscle stem cell protein called Pax3, which nudges the pluripotent cells to become skeletal muscle stem cells, which can then be exponentially expanded in culture. These Pax3-induced muscle stem cells were then transplanted back into the same strain of DMD mice from which the pluripotent stem cells were originally derived.

Pax3 and 7

When combined, these platforms created muscle-generating stem cells that would not be rejected by the body’s immune system. According to Perlingeiro, the transplanted cells performed very well in the dystrophic mice, and they generated functional muscle and responded to muscle fiber injury.

“We were pleased to find the newly formed myofibers expressed the markers of the correction, including utrophin,” said Perlingeiro, a Lillehei endowed scholar within the Lillehei Heart Institute and an associate professor in the University of Minnesota Medical School. “However, a very important question following transplantation is if these corrected cells would self-renew, and produce new muscle stem cells in addition to the new muscle fibers.”

By injuring the transplanted muscle and watching it repair itself, the researchers demonstrated that the transplanted muscle stem cells endowed the recipient mice with fully functional muscle cells. This latest project provides the proof-of-principle for the feasibility of combining induced pluripotent stem cell technology and genetic correction to treat muscular dystrophy.

“Utilizing corrected induced pluripotent stem cells to target this specific genetic disease proved effective in restoring function,” said Antonio Filareto, Ph.D., a postdoctoral fellow in Perlingeiro’s laboratory and the lead author on the study. “These are very exciting times for research on muscular dystrophy therapies.”

These studies pave the way for testing this approach in a clinical trial that would use reprogrammed human pluripotent cells from muscular dystrophy patients.

According to Perlingeiro, “Developing methods to genetically repair muscular dystrophy in human cells, and demonstrating efficacy of muscle derived from these cells are critical near-term milestones, both for the field and for our laboratory. Testing in animal models is essential to developing effective technologies, but we remained focused on bringing these technologies into use in human cells and setting the stage for trials in human patients.”

This research was published in Nature Communications.

Article written by: mburatov

PLURIPOTENT CELLS DISCOVERED IN ADULT BREAST TISSUE

In STEM CELLS IN THE NEWS on March 12, 2013 at 9:00 am

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The top middle panel shows endogenous pluripotent somatic (ePS) cells, which can give rise to many tissue derivatives, including pancreas, bone, intestine, breast and cartilage cells.

“More evidence that any part of the body associated with reproduction has powerful stem cells with significant regenerative abilities!” – DG

New Type of Pluripotent Cell Discovered In Adult Breast Tissue

UC San Francisco researchers have found that certain rare cells extracted from adult breast tissue can be instructed to become different types of cells – a discovery that could have important potential for regenerative medicine.  As with human embryonic stem cells, the newly found cells are pluripotent, or capable of turning into most cell types, the authors said. The scientists discovered that when the cells were put either in mice, or in cell culture, the cells could differentiate to produce multiple cell types, including those that proceed to make heart, intestine, brain, pancreas and even cartilage.  The finding is significant, the authors said, because scientists previously believed that pluripotent cells did not exist in the body after the embryonic stage of human development.

“The ability of cells from an adult body to make so many tissue derivatives was completely unexpected,” said senior author Thea D. Tlsty, PhD, a UCSF professor of pathology. “When we saw that they could make cartilage, bone, gut, brain, pancreas cells – and even beating heart tissue – we were excited and intrigued.”

Though the newly discovered cells share some characteristics of embryonic stem cells, they appear to be unique to themselves, said Tlsty. They are mortal and genetically stable – characteristics that are barriers to subsequent cancer formation, which is a factor that could prove valuable if the cells are to be used for regenerative medicine, she explained. By contrast, human embryonic stem cells as well as engineered induced pluripotent stem cells, also known as iPS cells, are immortal and genetically unstable.

Additionally, the cells can expand to an extensive yet finite number before they stop growing. One cell can grow for almost 60 population doublings, producing in excess of one billion daughter cells, conceptually providing enough cells to help in the recovery of damaged or diseased tissue.  The scientists are currently searching for the rare cells in other organs of the body. They hypothesize that these “universal patch kits” are scattered throughout the body of adult men and women.

The special cells were discovered and isolated in healthy breast tissue from women of various ages and ethnicities who were undergoing breast reductions. All tissues used in the study were devoid of visible disease or contamination.

From Breast Tissue to Beating Heart Cells

Even a single one of these endogenous pluripotent somatic (ePS) cells, when placed in the appropriate conditions, exhibited the same pluripotent power to self-renew and to generate multiple lineages – both in vitro and in vivo – as embryonic stem cells. The cells could develop into any of the three germ layers: endoderm (such as the pancreas and gastrointestinal tract), the mesoderm (bone, heart muscle, blood vessel), or ectoderm (breast tissues and nervous system).

For example, when properly instructed, some ePS cells made human breast tissue that produced milk in transplanted mice, while other cells generated cartilage structures. To the surprise of the researchers, when the cells were differentiated into heart muscle, they even demonstrated the spontaneous beating seen in cardiomyocytes, or “beating heart” cells.

“The cells we describe here exist in the body devoid of commitment,” the authors wrote. “Taken together, these studies provide morphological, molecular and functional evidence of lineage plasticity of these cells. They will make human milk, bone, fat – they will beat like a heart.”

Only a small fraction of certain mammary cells have “this complete and sustained” unique profile capable of morphing themselves, the researchers said.

“Future research will tell us if we lose access to these cells as we age, if they are found in all tissues, and if they can be used to rescue diseased tissues,” said Tlsty.

“The observation that rare cells within an adult human body have the capacity to differentiate into many tissue types under different physiological cues will facilitate a fascinating area of research into the physiology and therapeutic potential of these cells,” said lead author Somdutta Roy, PhD, Department of Pathology and the UCSF Helen Diller Family Comprehensive Cancer Center.

To read entire article – http://www.ucsf.edu

JAPAN TO HOLD FIRST STEM CELL CLINICAL TRIAL

In ALL ARTICLES, SCIENCE & STEM CELLS, STEM CELLS IN THE NEWS on February 15, 2013 at 9:00 am

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World’s first stem cell clinical trial

Researchers in Japan are looking to use the recent discoveries of Nobel Prize winning Shinya Yamanaka to treat a degenerative eye disease in what would be the world’s first clinical trial of induced pluripotent stem cells (iPS cells). An ethics committee at the Institute for Biomedical Research and Innovation gave its approval this week for the trial, meaning work could begin as early as the 2013 fiscal year.

Scientists plan to use iPS cells in a therapy for age-related macular degeneration, or vision loss. The trial will be conducted by a team led by Dr. Masayo Takahashi, and will be done in cooperation with Riken, a scientific research foundation affiliated with Japan’s Ministry of Science and Technology.

Age-related macular degeneration mostly occurs in people who are middle-aged or older, and, if left untreated, often leads to blindness. The current drugs on the market are known for only treating symptoms and not fighting the disease itself. The goal of the clinical trial is to create retinal cell sheets from iPS cells, which take the form of any other cells from the body, and transplant them into patients’ eyes. Six patients, all aged 50 or older and for whom existing drugs do not work, will be chosen from the institute’s hospital and, if successful, have corrected vision below 0.3 on the Japanese scale. The Japanese government has already stated it will be spending 110 billion yen (approx. $1.18 billion) over the next 10 years to sponsor research on the application of iPS cells.

“Japan is yet another country that has envisioned the potential stem cell therapies hold for regenerative medicine. ” – DG

To see full article click HERE.

KILLER T-CELLS PRODUCED TO ATTACK DISEASE

In ALL ARTICLES, SCIENCE & STEM CELLS, STEM CELLS IN THE NEWS on January 14, 2013 at 9:00 am

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Cells Grown By Japanese Researchers Kills Cancer

A team of researchers from both the University of Tokyo and the Riken Research Centre for Allergy and Immunology may have found a cure for HIV and Cancer. The research team was able to “extract live T-cells, the vital powerhouses of the human immune system, from patients, specifically targeting specialized cytotoxic T-cells which have the ability to recognize and attack signs of infection.  Researchers then converted the T-cells back to induced pluripotent stem cells (iPS) by exposing them to a group of compounds called the “Yamanaka factors,” in part so they could study the stem cells’ differentiation processes. Then the team reconverted the stem cells back into specialized disease-fighters, the T-cells known as “killer T-cells”or “killer T lymphocytes.” Among other critical findings, researchers discovered that the skin-cancer fighting T-cells remained capable of producing the crucial anti-tumor compound interferon.

“Stem cells can be grown at a much faster pace in a laboratory than in the human body, enabling researchers to create killer T lymphocytes that are—at least theoretically—ready for therapeutic human injection.”

“While the iPS cells did reconvert back into their original specializations, it’s unsure whether lab-grown cells will behave similarly to the immune system’s own disease-fighters when injected into the human body. Furthermore, the risk of rejection is high when cells from one patient are grown and converted for use in another.  Perhaps most importantly, it’s hard to predict whether cells that fight cancer in the lab will restrict their deadly effects to cancer cells in the body. Lead researcher Hiroshi Kawamoto, in a press release from the Riken Center, states, “the next step will be to test whether these T cells can selectively kill tumor cells but not other cells in the body.” It’s possible that lab-grown cells could attack normal, healthy human cells after therapeutic injection.  But medical and scientific experts remain cautiously optimistic.

“A lot of work needs to be done before we can think about clinical trials, but the initial data are promising.” Said Dr. Dusko Ilic, Senior Lecturer in Stem Cell Science, King’s College London.

The main challenge researchers face is the cost of producing large amounts of killer T lymphocytes safely. Numerous expensive confirmatory studies and trials will need to be conducted before the new therapy is approved for human use.

“The implications for the health of humankind, on the other hand, are immediate, and clear. If science has indeed provided a novel means of fighting our most persistent and deadly infections, untold amounts of suffering could be mitigated—and, ultimately, eradicated.”

http://www.usnewsuniversitydirectory.com/articles/cells-grown-by-japanese-researchers-kills-cancer_12861.aspx#.UPNh2GeAoTA

STEM CELLS TECHNOLOGY HARNESSES POTENTIAL TO USE A PATIENTS IMMUNE CELLS TO FIGHT DISEASE

In ALL ARTICLES, SCIENCE & STEM CELLS, STEM CELLS IN THE NEWS on January 5, 2013 at 10:22 am

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“In two separate papers contained in the January 4th issue of the Cell Press Journal, Scientists in Japan have used old immune T-cells and regenerated them into T-cells that multiplied in greater numbers, had longer life spans and showed a greater ability to target diseased cells in HIV-infected cells and cancer cells. These discoveries could lead to more effective immune therapies.”

STEM CELLS TECHNOLOGY HARNESSES POTENTIAL TO USE A PATIENTS IMMUNE CELLS TO FIGHT DISEASE

The human body contains immune cells programmed to fight cancer and viral infections, but they often have short life spans and are not numerous enough to overcome attacks by particularly aggressive malignancies or invasions.

The techniques the groups employed involved using known factors to revert mature immune T cells into induced pluripotent stem cells (iPSCs), which can differentiate into virtually any of the body’s different cell types. The researchers then expanded these iPSCs and later coaxed them to re-differentiate back into T cells. Importantly, the newly made T cells were “rejuvenated” with increased growth potential and lifespan, while retaining their original ability to target cancer and HIV-infected cells. These findings suggest that manipulating T cells using iPSC techniques could be useful for future development of more effective immune therapies.

In one study, investigators used T cells from an HIV-infected patient. The re-differentiated cells they generated had an unlimited lifespan and contained long telomeres, or caps, on the ends of their chromosomes, which protect cells from aging. This is significant because normal aging of T cells limits their expansion, making them inefficient as therapies. “The system we established provides ‘young and active’ T cells for adoptive immunotherapy against viral infection or cancers,” says senior author Dr. Hiromitsu Nakauchi, of the University of Tokyo.

The other research team focused on T cells from a patient with malignant melanoma. The re-differentiated cells they created recognized the protein MART-1, which is commonly expressed on melanoma tumors. “The next step we are going to do is examine whether these regenerated T cells can selectively kill tumor cells but not other healthy tissues. If such cells are developed, these cells might be directly applied to patients,” says senior author Dr. Hiroshi Kawamoto, of the RIKEN Research Center for Allergy and Immunology. “This could be realized in the not-so-distant future.”

http://www.sciencedaily.com

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TASK FORCE REJECTS EMBRYONIC STEM CELLS

In STEM CELLS IN THE NEWS on December 31, 2012 at 9:32 am
(BIS Photo/Patrick Hanna)

(BIS Photo/Patrick Hanna)

The National Task Force on Stem Cell Therapy Treatment, which comprises a group of respected doctors, with influence from the archdiocese, proposed to the Minister of Health, Dr. Perry Gomez calling for an overhaul of existing legislation concerning medical tourism in the Bahamas.  Stem Cell research and therapy has the potential to generate over $100 million in the medical tourism industry, according to the government’s task force, which delivered its verdict on the country’s proposed plunge into the controversial science yesterday.  “We put together the framework for stem cell work to be carried out to the benefit of Bahamians in an ethical way and to support the potential for a medical tourism industry, and we delved into the specifics of what can be done and what should not be done.” said Dr Arthur Porter.

-DG

The National Task Force on Stem Cell Therapy Treatment has recommended to the Bahamas Government that embryonic stem cells should not be used to create human stem cells in this country, said the Task Force’s chairman and managing director of the Cancer Centre, Professor Arthur T. Porter.

Professor Porter presented a copy of the Task Force’s recommendations to Minister of Health the Hon. Dr. Perry Gomez during a press conference held at the Ministry of Health, Thursday, December 27, 2012.  The Chairman told Dr. Gomez that the Task Force’s members unanimously support all of the recommendations within the report.

In November 2012, the Bahamas Government appointed the Task Force to develop a series of recommendations regarding the possible use of Stem Cell Therapy in The Bahamas.  The Committee had to weigh all the pros and cons associated with Stem Cell use, including the more controversial use of embryonic Stem Cells. The Task Force also had to look at how adult Stem Cells would be used.

Members of the Task Force include Dr. Robin Roberts, Director, University of the West Indies School of Clinical Medicine and Research, Bahamas Campus; Rev. Angela Palacious, Anglican Archdiocese; Dr. Duane Sands, Senior Cardiovascular Surgeon, Princess Margaret Hospital; Dr. Paul Ward, Chief of Services, Rand Memorial Hospital, Grand Bahama; Dr. Barrett McCartney, Senior Anesthesiologist and Pain Specialist, Doctors Hospital and Dr. Indira Martin, Laboratory Research, Ministry of Health.

Dr. Wesley Francis, President of the Medical Association of The Bahamas; Dr. Glen Beneby, Medical Director, Public Hospitals Authority and Mrs. Michelle Pindling-Sands, Attorney-at-law, also sit on the Task Force.  When the Task Force was first introduced, Professor Porter explained that there are two types of stem cells.

“Embryonic cells usually derive from a five-day embryo or earlier, which have the ability to become any cell in the body whether a brain cell, a fat cell or a nerve cell. They are pluripotent (capable of differentiating into one of many cell types).

“The second type are the adult stem cells, which are smaller in quantity and can be found in most tissue and organ systems, but which lack the flexibility of what they can be, and so scientist have tried to take some of the adult Stem Cells and make them able to be more or less like embryonic stem cells to sort of get around the problem.”  Professor Porter explained that during the Task Force’s deliberations, it was found that there is no need for the use of embryonic Stem Cells, because research is finding that adult Stem Cells can be transformed to be able to act as Induced Pluripotent Stem Cells.  As a result, he said there is no need to focus on embryonic stem cells in The Bahamas.

Professor Porter said the use of umbilical cord blood, which has been used for over 15 years in different parts of the world, should also be permitted in The Bahamas.  “The use of somatic cell nuclear transfer, which is a type of technique in which adult Stem Cells are encouraged to behave, as early Stem Cells should also be used.  “But again recognizing that we are on the frontiers of new science, so the appropriate clinical trials, the appropriate committees, the appropriate ethics support should be given to the use of these areas.”

Professor Porter said many have asked the Task Force for an opinion regarding reproductive human cloning. “The Task Force was quite committed in its opinion that reproductive cloning should not be permitted.”  He added that the Task Force felt that it was important that there be widespread education and consultation with various stakeholder groups that will be involved in making the ultimate decision, so people would become aware of the importance of Stem Cells, some of the ethical issues and be able to opine in this regard.  Professor Porter said the Task Force believed that Stem Cells would be an important part of the country’s medical tourism thrust, but the Government needs to broadly review what is necessary for a successful medical tourism industry.  Dr. Sands added, “We have to understand that this is a rapidly evolving field and there are many countries in the world that have embraced medical tourism and as such have tried desperately to ensure the process of approval or the rapid acceleration of new projects is done in a timely fashion.  “Similarly, efforts have been made to ensure that phenomenal scrutiny of the proposed projects, the participants, etc., is carefully done.

He said legislation in The Bahamas has to be robust enough to protect the integrity and the reputation of the country while at the same time promoting good science and this is an on-going process. “We need to make sure the laws are constantly keeping up with what is happening on the ground.”  Dr. Gomez said after he reviews the report, he would present it to Cabinet early next year so that policies can be made surrounding Stem Cell Therapy in the country.

http://www.bahamaislandsinfo.com

PANCREATIC STEM CELLS, ONE STEP CLOSER TO A CURE

In SCIENCE & STEM CELLS, STEM CELLS IN THE NEWS on December 12, 2012 at 9:00 am

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Millions of people in the United States suffer with type 1 diabetes and are unable to produce sufficient insulin. “As of 2010, 25.8 million people—8.3% of the population—have diabetes; 1.9 million new cases of diabetes were diagnosed in people aged 20 years or older in 2010.” (http://www.cdc.gov/diabetes/consumer/research.htm) “… About 27 percent of those with diabetes—7 million Americans—do not know they have the disease. Pre-diabetes affects 35 percent of adults aged 20 and older. (http://www.cdc.gov/media/releases/2011/p0126_diabetes.html) The potential to transplant insulin-producing cells into patients suffering from Diabetes would be a critical step forward and could offer hope for a long-term cure.
-DG

The potential to one day treat type 1 diabetes using transplants of insulin-producing beta-cells derived from pancreatic progenitors may have just crept a tad closer, if findings by a group of researchers at the University of California, San Diego (UCSD) can be verified. The team has identified a cell surface marker on a subpopulation of cells in the pancreas that appears to identify them as pancreatic stem cells (PnSCs), a cell type which has never actually been firmly demonstrated in human or animal tissues.

A current approach to cell replacement therapy for diabetes involves the transplantation of pancreatic islets, which involves numerous transplant procedures. Although it is feasibly possible to derive insulin-producing cells from either human embryonic stem cells (hESCs) or induced pluripotent stem cells (iPSCs), there are technical issues which have yet to be solved. What is ideally needed is a source of stem cells derived directly from the pancreas that can readily be prompted to differentiate into the desired cell type.

Research by Alberto Hayek, Ph.D., and colleagues now indicates that human pancreatic ductal cells that express the cell surface stem cell marker stage-specific embryonic antigen 4 (SSEA4) may represent this elusive population of PnSCs that has long been postulated but never quite isolated. The cells, located in the exocrine portion of the adult human pancreas but not inside islets themselves, also express ductal, pancreatic progenitor, and stem cell protein markers. Interestingly, the investigators found that SSEA4-expressing cells isolated from fetal pancreatic tissue additionally express a recognized marker of endocrine progenitor cells.

Notably, when the UCSDF team then isolated adult human pancreatic SSEA4+ cells and cultured them in media containing high levels of glucose and B27 supplements, the cells formed aggregate-like spheres and differentiated readily into pancreatic hormone-expressing cells.
“Accumulated evidence supports the concept that pancreatic stem/progenitor cells may originate in the pancreatic duct, where they reside in a quiescent stage,” the authors remark. “We are first to identify SSEA4+ cells in the adult human pancreas with characteristics of pancreatic progenitors. Further clonal analysis would confirm their stemness…. The discovery of specific markers for the identification and purification of human PnSCs would greatly facilitate studies aimed at the expansion of these cells and the development of targeting tools for their potential induction to insulin-producing cells.

Dr. Hayek et al., report on their findings in BioResearch Open Access, in a paper titled “Is stage-specific embryonic antigen 4 a marker for human ductal/stem/progenitor cells?”

http://www.genengnews.com/gen-news-highlights/pancreatic-stem-cells-could-they-treat-diabetes/81247218/

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