Tag Archives: stem cells

Protein that keeps stem cells poised for action identified

From dnaindia.com

Scientists from Stanford University School of Medicine have identified a protein that appears to play a critical role in keeping stem cells poised to quickly become more specialised cell types.

The protein called Jarid2 maintains a delicate balancing act – one that both recruits other regulatory proteins to genes important in differentiation and also modulates their activity to keep them in a state of ongoing readiness.

“Understanding how only the relevant genes are targeted and remain poised for action is a hot topic in embryonic stem cell research,” said Dr Joanna Wysocka, assistant professor of developmental biology and of chemical and systems biology.

“Our results shed light on both these questions,” Wysocka added.

Jarid2 works through a protein complex called PRC2, for Polycomb Repressive Complex 2, which is necessary to regulate the expression of developmentally important genes in many types of cells.

According to the researchers, PRC2 activity allows the cell to carefully manage its degree of readiness for the subsequent unwrapping and expression of genes involved in differentiation of the embryonic stem cells into more specialised cells.

“It was just as we would have predicted,” said Wysocka. “Without Jarid2, which keeps the genes silent yet poised for activation, the embryos stop developing.”

The researchers now plan to further investigate the mechanism by which Jarid2 summons PRC2 to differentiation-specific genes in the stem cells, and how it affects gene expression.

The interaction may be important in human cancers as well.

The study appears in journal Cell.

Pioneering stem cell treatment restores sight

By Richard Alleyne, Telegraph.co.uk

Russell Turnbull, 38, lost most of the vision in his right eye when he had ammonia sprayed into it as he tried to break up a fight on a late night bus journey home.

The attack, which badly burned and scarred his cornea, left him with permanent blurred sight and pain whenever he blinked.

Now however his sight has been almost fully restored thanks to a new technique where doctors regrow the outside membrane of his cornea from stem cells taken from his healthy eye.

The new operation involves cutting away a millimetre squared section of his left eye complete with stem cells and growing it to 400 times that size in the laboratory.

The new outer skin of the eye is then stitched onto the badly damaged cornea in place of the damaged membrane.

The technique, developed by scientists and eye surgeons at the North East England Stem Cell Institute (NESCI). has been used on eight patients and for most of them including Mr Turnbull it has almost completely restored their vision.

Dr Francisco Figueiredo, Consultant Eye Surgeon at NESCI team, who co-led the project, said: “Corneal cloudiness has been estimated to cause blindness in eight million people worldwide each year.

“The stem cell treatment option is aimed at total cure rather than symptom relief only. This new treatment will alleviate patient suffering and remove the need for long term multiple medications as well as returning the patient to functional and social independence.”

Dr Sajjad Ahmad, who developed the Newcastle method for culturing limbal stem cells, said “This study shows that stem cell research conducted in the laboratory can have a major impact on the quality of life of patients with corneal disease. This work has been a team effort involving stem cell researchers and hospital doctors working together effectively.”

A larger study involving 24 new patients is currently underway with funding from the UK’s Medical Research Council.

Mr Turnbull, a storeman, said: “The operation was a complete success and I now have my sight back. This really has given me my life back.”

Details of the treatment have been published in the American journal, Stem Cells.

Stem Cells Save Legs

From Ivanhoe Newswire

Two million people in the United Sates suffer from critical limb ischemia, or poor blood flow to their legs. As the number of diabetics soars, the number of those affected is expected to almost double by 2020. The condition causes severe pain and chronic infection. Surgery to open blocked veins is often the treatment, but for 40 percent of patients it doesn’t work and they lose their leg to amputation. Now, doctors are turning to a patient’s own body to heal itself.

Cathy Ballzigler doesn’t take one moment of her life for granted. A few years ago, she came close to losing it.

“He told my husband that I was about 11 weeks from dying,” Ballzigler told Ivanhoe.

Ballzigler was losing feeling in her leg. Her doctor said it was critical limb ischemia. The arteries in her leg were blocked. A year of surgeries didn’t help, and she was told amputation was her last resort.

“He really wanted to take my leg off, but I would beg and plead and say don’t take it off, just do what you can,” Ballzigler said.

“They’ll often have unresolving wounds — wounds that just will not heal because they don’t have the blood supply to the tissues,” George Geils, Jr., M.D., medical director of the Blood and Marrow Transplant Program at Roper St. Francis Healthcare in Charleston, S.C., told Ivanhoe.

An experimental 20-minute procedure is helping patients who’ve run out of options. Doctors remove stem cells from the pelvic bone and inject them back into the leg along the course of the diseased artery.

“If you take those stem cells out and put them into another organ, they can actually function and grow a different tissue in the body,” Dr. Geils said.

After four to six weeks, new arteries start to grow.

“I went from 17 percent oxygen to over 66 percent oxygen after my surgery,” Ballzigler said.

Today, she toasts to her future and is thankful for a second chance.

Smoking, diabetes and high blood pressure put patients at risk for critical limb ischemia. The stem cell treatment costs less than conventional limb-saving procedures like bypass surgery and stents.

See Related Article:
Bioheart Makes Breakthrough In Critical Limb Ischemia Therapy With Stem Cells Obtained From Fat Tissue

Stem cell therapies for hearts inching closer to wide use

By Elizabeth Landau, CNN.com

If you’ve just had your first heart attack, doctors may one day be able to reverse the damage done with stem cell therapy.

An intravenous method of injecting stem cells into patients who had experienced heart attacks within the previous 10 days suggested that this method works to repair — not just manage — heart damage, a recent study found.

The study is a step forward in a field in which a lot of approaches have been tried in animals and preliminary human trials, but none has been approved for widespread clinical use for heart patients.

The new results are a milestone in stem cell research, and for patients, said Jeffrey Karp, a researcher at Brigham and Women’s Hospital in Boston, Massachusetts, who runs a stem cell biology lab at Harvard University. He was not involved in the study.

Most current clinical approaches are focused on managing problems, not addressing the root of the damage, he said.

“Many patients who have a heart attack will go on to suffer heart failure,” he said. “It’s imperative to try and fix the root of the problem as quickly as possible.”

The research, published in the Journal of the American College of Cardiology, were part of a phase I study that set out to show safety. The trial has moved on to phase II, which is taking place in 50 hospitals in the United States, said Dr. Joshua Hare, director of the Interdisciplinary Stem Cell Institute at the University of Miami’s Miller School of Medicine and lead author of the study.

“We’re looking on the time frame here of five years, in the best-case scenario, to have approved cardiac stem cell therapies,” Hare said.

Coronary heart disease, which causes heart attacks and angina — chest pain resulting from the heart not getting enough blood — is the leading cause of death in the United States, with nearly 450,000 in 2005, according to the American Heart Association. About 1.1 million people have attacks occur in the United States each year, according to the National Heart Lung and Blood Institute.

The particular kind of cells used in this research are called mesenchymal stem cells, and come from adults, not embryos.

The researchers are using a mesenchymal stem cell therapy that is marketed by Osiris Therapeutics Inc. under the name Prochymal. The drug, which consists of stem cells from donor bone marrow, gets injected into the vein. The cells then travel through the bloodstream and take up residence in the heart.

Mesenchymal stem cells have some natural homing capability, and injury serves as a homing beacon for them, Karp said.

The stem cells reduce the amount of scar tissue and increase the pumping strength of the heart in heart attack patients, Hare said. To a limited extent, they also grow new heart muscle.

The phase I results from 53 patients are not definitive proof that the treatment is effective, but do suggest so, Hare said. In accordance with clinical trial regulations set by the Food and Drug Administration, phase I is meant to show safety, while phase II and phase III trials are done on a larger group of subjects and evaluate how well the drug works.

In this trial, patients’ doses ranged from 35 million cells to 350 million cells. There was no change or increase in side effects in treatments getting higher doses of cells, but it seemed that the treatment was more effective — at least in terms of reducing electrical problems — in the high dose group, he said.

In separate trials, researchers are looking at how the technique works in patients who have had heart attacks many month or years in the past, Hare said.

The study shows the results of a six-month follow-up with patients in 2007, and researchers are presently working with data from the two-year follow-up.

More broadly, besides bone marrow transplantations, there have not been any major successes in the stem cell field in terms of helping large numbers of patients, Karp said.

“Mesenchymal stem cells are poised to really be the next major success in cell therapy that could be used to treat tens of thousands of patients,” he said.

There are several advantages to using mesenchymal stem cells for heart therapy. First, they are adult stem cells, so there are no ethical issues that surround research on embryonic stem cells. Secondly, at least from a safety perspective, mesenchymal stem cells do not require matching — any donor can give cells to any other donor, and no immunosuppresant drugs are necessary, he said.

Still, millions of cells are required in order for enough stem cells to reach the heart and have a therapeutic benefit, and it’s costly to get the required numbers of cells for each patient, Karp said. An area of improvement would be making the stem cell treatment more efficient, he said.

“If we could increase the number of cells that could reach the heart, that would have significant advantages to this approach,” Karp said.

This method of intravenous injection means that the procedure theoretically could be performed in a doctor’s office or clinic, increasing the accesibility to patients, Karp said.

A more invasive stem cell delivery technique has been showing positive results in other clinical trials, involving injecting patients’ own stem cells directly into heart muscle.

The largest national stem cell study for heart disease, sponsored by Baxter Inc., uses this surgical method, and recently announced success in a 12-month phase II trial for patients with severe angina. Researchers found that participants had less pain and an improved ability to walk.

Because stem cells are delivered through a catheter in this method, there is a risk of perforation of about 1 percent, Dr. Douglas Losordo, cardiologist at Northwestern Memorial Hospital in Chicago, Illinois, told CNN earlier this year. The drug, GCSF, which mobilizes stem cells, also carries a small risk of blood clotting.

For the Osiris trials, further research is ongoing determine whether patients would benefit more from more infusions of the stem cells, or if it’s better for the stem cells to come from their own bodies instead of from a donor, Hare said.

While there’s less chance of a person’s body rejecting his or her own stem cells than from a donor, there is a time delay, he said. Taking bone marrow and amplifying the stem cells in it could take up to five weeks, whereas donor cells could be made readily available, he said. On the other hand, it is unclear whether a donor could potentially transmit a disease to the recipient in the process.

If you are interested in enrolling in a clinical trial, you can find one at clinicaltrials.gov.  The Orisis trial is still recruiting participants.

Ground-breaking stem cell treatment being used on dogs

By Christi Myers, abclocal.go.com

There’s one area of medicine where vets may be ahead of physicians — in stem cell therapy for arthritis and joint pain. Some Houston pets are already feeling the effects of stem cells injections. It’s a treatment that’s just become available here. The Canine Health Institute has performed six stem cell transplants on dogs.

Sally is only a year old, but she has so much pain in her hips, she moves like an old dog.

Sally’s owner Charlotte Liberda said, “We want her to run, to play, to jump on the bed.”

Liberda, who rescued Sally from the pound, had an idea. She’d heard about stem cells and went to the Canine Health Institute in Houston to give it a shot. Stem cells are the same cutting edge human treatment that can also help dogs.

Dr. Adrianne Brode, DVM, explained, “Our main goal would be to treat orthopedic cases, arthritis, cruciate injuries, post-operative kind of things. Those are the kind of treatments we know that stem cells can make a big difference.”

They get the stem cells from the fat in Sally’s belly. They’re using a machine that’s used to get human stem cells and when they put the fat in, it separates the fat from the stem cells.

It’s one of half a dozen machines in the world that can isolate stem cells right in the operating room. That saves having to do two surgeries on the animal. Four other stem cell machines like this one are in human hospitals, including Houston’s Texas Heart Institute.

The separation procedure takes more than an hour. Dr. Brode counts the stem cells and gives Sally a shot of stem cells in each hip.

Daisy the beagle got stem cell therapy two weeks ago for pain after surgery.

Daisy’s owner Suzanne Taylor said, “I noticed a dramatic improvement within one week after the procedure. She was able to walk on all four legs and she wasn’t in so much pain and seemed much happier.”

Dexter also had stem cell therapy for pain after surgery to repair a torn ligament.

“He was better, better, better,” said Dexter’s owner Kirby Attwell. “I’m hesitant because it’s so soon after surgery, but he had a real improvement almost immediately.”

“They’re walking around better, not limping as much and they’re all doing very good so far,” Dr. Brode said.

This great idea of taking stem cells from your fat is being tested in humans here. Houston researchers at the Texas Heart Institute use the same machine to take stem cells from a patient’s fat, and use them to strengthen the heart.

See video here.

NIH approves 27 more stem cell lines

By Dan Vergano, blogs.USAtoday.com

National Institutes of Health chief Francis Collins approved another 27 human embryonic stem cell lines for federal research funding Monday, but limited support to diabetes-related pancreatic cell experiments.

The 27 Harvard University cell lines join 13 from Children’s Hospital Boston added earlier this month to a NIH stem cell registry. Human embryonic stem cells are the precursors to every type of tissue. Cell “lines”, or colonies, are grown from the collected inner cells of an embryo destroyed in the process of collection. Researchers hope to study organ development, screen drugs and someday perhaps grow rejection-free transplant tissues from the cells.

In an Oct. 12 application for NIH approval, the Harvard researchers had noted they gathered the embryos from donations by fertility clinic patients, using consent forms that listed their use as diabetes research. For that reason, “NIH-funded research with this line is limited,” says the registry, to “study the embryonic development of (tissue) with a focus on pancreatic formation,” with the aim of “producing cells that produce insulin, for transplantation into diabetics.” An advisory committee last week had recommended the limitation, and Collins apparently agreed with their recommendation.

The Harvard cells have been used in privately-funded studies of ALS, Alzheimer’s disease, Huntington’s disease, Parkinson’s disease, spinal injury, heart disease, cancer infertility and other ailments. A Proceedings of the National Academies of Science journal report last year called them the “gold standard”  for comparison with cells claimed to possess tissue-forming properties.

The approval puts 40 cell lines on the NIH registry, beating the Bush Administration 2001 to 2008 total of 21 lines on its registry.

Scientists use Dental Stem Cells in First Successful Human Transplant

From Benzinga.com

BioEDEN, the world-leader in dental stem cell extraction and storage, is celebrating the first successful human medical trial using stem cells from teeth.

Scientists at The Second University of Naples, Italy have successfully used stem cells taken from dental pulp found in teeth to create new bone tissue and graft it onto a human jaw. The success yields a vast number of medical possibilities for dental stem cells, and for those people who store them for future use.

BioEDEN, based in Daresbury, Cheshire, with laboratory facilities in Austin Texas, and Bangkok Thailand, holds the global patent for the extraction, cryopreservation and storage of dental stem cells for medical use. BioEDEN stores stem cells found in children’s milk teeth, with the hope that one day they will save the donor’s life by being able to repair damaged or diseased tissue.

“For BioEDEN, this achievement is an immaculate demonstration of how vital dental stem cells will come to be in the future of medicine,” said Jim Curtis, Managing Director of BioEDEN. “This is the first time dental stem cell research has moved from the laboratory to human medical trials, and the announcement is truly groundbreaking. It opens up a great deal of medical hope for the future.”

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New human embryonic stem cell lines eligible for federal research dollars for the first time since 2001

By Karen Kaplan,  LATimes.com

The number of human embryonic stem cell lines eligible to be used in government-funded research just went up by 13.

The National Institutes of Health announced today that 11 new cell lines from Dr. George Daley at Children’s Hospital Boston and two lines from Ali Brivanlou at Rockefeller University in New York became the first additions to the NIH Human Embryonic Stem Cell Registry since President Obama reversed his predecessor’s policy. Under President Bush, only human embryonic stem cells prior to August 2001 were eligible for federal funding.

The new lines were derived from embryos created for fertility treatments and donated by couples who went through a rigorous informed consent process.

And more may be on the way. The NIH said that 96 more lines have been submitted by researchers, including 20 that will be vetted by an advisory committee on Friday.

The additions come nearly nine months after Obama signed an executive order that directed the NIH to make federal research funds available to newer lines of human embryonic stem cells. Scientists were overjoyed and said the decision would accelerate the pace of research into such ailments as diabetes, Alzheimer’s and spinal cord injuries. Details of the policy are available here.

Stem Cells’ Next Use: Fighting Extinction

By JONATHAN PARKINSON, VoiceofSandiego.org

It’s a lonely world for the two northern white rhinos at Escondido’s Wild Animal Park. They are among less than a dozen of their kind left on Earth.

Conservationists work constantly through habitat protection and other means to save these and other endangered species. And now they are adding a new technology to their list of possible solutions to extinction — stem cells.

Scientists at the San Diego Zoo’s Institute for Conservation are working on two separate projects that employ some of the same stem cell breakthroughs that might someday treat disorders like Alzheimer’s and Parkinson’s diseases in humans.

“This is a very preliminary experiment,” said Oliver Ryder, director of genetics at the Institute for Conservation Research. “We want to see if the process that’s worked on human cells will work in animals.”

Ryder’s group wants to reprogram adult cells from drill monkeys and northern white rhinos into stem cells. Using a type of virus called a retrovirus, scientists introduce genes into the DNA of an adult cell that cause it to behave like an embryonic stem cell, a versatile cell that can divide to form any other cell type in the body.

The Zoo researchers are working in collaboration with world-renowned stem cell researcher Jeanne Loring and her lab at the Scripps Research Institute.

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First Reconstitution of an Epidermis from Human Embryonic Stem Cells

From ScienceDaily.com

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