Diabetes Reversed in Mice Using stem Cells

Canadian scientists were able to reverse diabetes in mice with a human stem cell transplant, igniting hopes for a cure for the widespread disease, caused by the failure of the pancreas to produce enough insulin to stabilize blood sugar levels in humans.

A paper outlining the work, led by Timothy Kieffer of the University of British Columbia and conducted in partnership with New Jersey-based company BetaLogics, appeared in the journal Diabetes on Tuesday.

Diabetic mice were weaned off of insulin after receiving the pancreatic stem cell transplant, which restarted the cycle in which insulin production rises or falls based on blood sugar levels.  Three to four months later, the mice could maintain healthy blood sugar levels even after being fed a lot of sugar.

"We are very excited by these findings, but additional research is needed before this approach can be tested clinically in humans," Kieffer said in a statement on Tuesday.

The researchers cautioned that their study used mice that had a suppressed immune system, the better to prevent rejection of the transplanted cells.

"We now need to identify a suitable way of protecting the cells from immune attack so that the transplant can ultimately be performed in the absence of any immunosuppression," Kieffer said.

In 2009, a different team of researchers led by scientists from the University of Sao Paulo in Brazil and Northwestern University reported in the Journal of the American Medical Association that they were able to successfully reverse type 1 diabetes by injecting 8 patients with some of their own stem cells.

Some studies have shown that this kind of stem cell transplantation is only a temporary fix - after anywhere between six months to three years, the insulin-producing cells are again attacked by the patient's immune system.

SOURCE: Rezania et al. "Maturation of Human Embryonic Stem Cell-Derived Pancreatic Progenitors into Functional Islets Capable of Treating Pre-existing Diabetes in Mice." Diabetes 27 June 2012.

SPIONs Track Functioning of Stem Cells Inside Body

UK's Liverpool Scientists have developed a method to track the stem cells in our body, according to a new report.

Scientists from the University of Liverpool have developed new methods to track stem cells and the changes that happen to them after they have been in the body for a significant period of time.

Scientists "labeled" the cells with superparamagnetic iron oxide nanoparticles (SPIONs) before they were administered to the patients.

The magnetic resonance imaging (MRI) scans clearly showed movement of the stem cells and the scientists could determine whether the stem cells reached their intended target or not.

However, scientists warn that conditions within the body's cells can lead to the degradation of SPIONs and reduce the ability of MRI scans to pick up on their signal in the long-term.

To overcome this drawback, scientists are developing new methods to visualise SPION's in the cells before they enter the body to learn their performance in the long-term.

Photothermal technique, a unique optical imaging system is used to improve SPION labelling so that particles survive for longer and have minimal impact on the function of the transplanted cells.

"In order to fully explore this potential, however, more technological developments are needed to understand how stem cells behave in the body after transplantation.

If we can't monitor stem cells effectively, it can have serious implications for patient health. Studies have already shown that if cells migrate to the circulatory system, beyond their target organ or tissue site, then it can cause inflammation in the body," said Dr Lara Bogart, scientist at the University's Institute of Integrative Biology in a statement.

"Labelling stem cells is hugely valuable to tracking their movements in the body, but we need to know more about how the particles used interact with stem cells.

Using new imaging systems we can work out their precise location in the cell and how they behave over time.

We hope to use this information to improve understanding of the MRI signal that tracks SPIONs once stem cells have been transplanted," she added.

Stem cells are used to treat conditions such as leukaemia and have the potential to treat many more diseases and disorders where patient survival is reliant on organ and tissue donation.

Nature: Biologists grow human-eye precursor from stem cells

A stem-cell biologist has had an eye-opening success in his latest effort to mimic mammalian organ development in vitro.

Yoshiki Sasai of the RIKEN Center for Developmental Biology (CBD) in Kobe, Japan, has grown the precursor of a human eye in the lab.

The structure, called an optic cup, is 550 micrometres in diameter and contains multiple layers of retinal cells including photoreceptors.

The achievement has raised hopes that doctors may one day be able to repair damaged eyes in the clinic.

But for researchers at the annual meeting of the International Society for Stem Cell Research in Yokohama, Japan, where Sasai presented the findings this week, the most exciting thing is that the optic cup developed its structure without guidance from Sasai and his team.

The human eye is a complex structure — but the cues to build it come from inside the growing cells. Credit: Dougal Waters/Getty

“The morphology is the truly extraordinary thing,” says Austin Smith, director of the Centre for Stem Cell Research at the University of Cambridge, UK.

Until recently, stem-cell biologists had been able to grow embryonic stem-cells only into two-dimensional sheets. But over the past four years, Sasai has used mouse embryonic stem cells to grow well-organized, three-dimensional cerebral-cortex¹, pituitary-gland² and optic-cup³ tissue. His latest result marks the first time that anyone has managed a similar feat using human cells.

Read the full article here: Biologists grow human-eye precursor from stem cells : Nature

Sylene stenophylla plant regenerated from tissue of fossil fruit

This photo provided by the Institute of Cell Biophysics of the Russian Academy of Sciences show a Sylene stenophylla plant regenerated from tissue of fossil fruit. 

The plant has been regenerated from tissues found in a squirrel burrow that had been stuck in Siberian permafrost for over 30,000 years.

 It is the oldest plant ever to be regenerated and it is fertile, producing white flowers and viable seeds.

Picture: The Institute of Cell Biophysics of the Russian Academy of Sciences / AP

First Patients Shown to Improve With Embryonic Stem Cells

Before treatment, the 51-year-old graphic artist was legally blind, unable to read a single letter on a standard eye chart.

She has suffering from Stargardt's disease, the most common form of macular degeneration in young patients, since she was a teenager, and it was getting progressively worse.

A second patient, aged 78, suffered from dry macular degeneration -- the leading cause of blindness in the elderly -- and could not even see well enough to go shopping.

But after being treated with stem cells from a donated human embryo, both women have improved dramatically, researchers said on Monday.

Stem cells are master cells that can differentiate into any of the 200 kinds of cells in the human body.

Their results are the first-ever report of the medical use of stem cells taken from human embryos, making them crucial barometers of whether the controversial technique will ever find widespread therapeutic uses.

In a paper published online in The Lancet on Monday, physicians at the University of California, Los Angeles, and scientists at biotechnology company Advanced Cell Technology (ACT) report that the first two patients in the clinical trial suffered no adverse health effects from the treatment and seem to have benefited from it.

A week after having cells derived from a days-old embryo injected into her eye, the graphic artist could count fingers, and after one month she could read the top five letters on the eye chart.

She can see more color and contrast, has started using her computer, and for the first time in years can read her watch and thread a needle. The macular degeneration patient recently went to the mall for the first time in years.

The safety findings, not any vision improvement, is what people should focus on, said Dusko Ilic, senior lecturer in stem cell science at Kings College London, who was not involved in the work.

"If everyone expects that the blind patients will see after being treated ... it will end up as disaster," he said.

Nevertheless, advocates for the blind are already hailing the results. "At last we are seeing fruits of human embryonic stem cell research entering clinical trials," said Peter Coffey, Director of the London Project to Cure Blindness.

OBJECTIONS AND RISKS
Using human embryonic stem cells for research or treatment has incited controversy for ethical and medical reasons. Some opponents argue that because removing stem cells from days-old human embryos almost always destroys the embryo, the technique amounts to murder.

ACT is the only company currently testing human embryonic stem cells in study patients. Last November, stem-cell pioneer Geron announced that it was halting what had been the first-ever clinical trial of the cells-testing them in patients with spinal cord injuries - and leaving the field.

When Robert Lanza, chief scientific officer of ACT, approached ophthalmic surgeon Steven Schwartz of UCLA about leading the clinical trial, Schwartz asked for ethical advice from two of his patients: elderly nuns. They gave him the go-ahead, he said last year.

Even scientists who support stem cell research argue that they could be dangerous to use therapeutically. The very property that makes them so valuable in research - stem cells can morph into any of the kinds of cells in the human body - also makes them risky.

They can form teratomas, a type of tumor that arises when stem cells differentiate into a profusion of cell types.

Another concern is that transplanting cells derived from human embryos could be rejected by the patient's immune system. The ACT team got around that by targeting the eye, which is an "immuno-privileged" site that does not produce a strong immune response to foreign tissue.

In the study, physicians led by Schwartz injected what are called retinal epithelial cells into one eye of each patient.

RPE cells lie at the back of the eye and bathe the retina's rods and cones in substances called growth factors. When RPE cells die, as they do in macular degeneration, so do the photoreceptors, eventually causing blindness.

Transplanting RPE cells grown from stem cells, Lanza reasoned when he began this research almost a decade ago, might rejuvenate the eye's rods and cones, restoring lost vision.

To produce RPE cells, Lanza and his colleagues arranged to obtain days-old embryos created by in vitro fertilization.

The parents, who no longer wanted the embryos, donated them for research. The scientists then removed a single stem cell from one embryo, grew it in the lab to obtain millions of cells, and differentiated them into RPE cells.

The primary purpose of the clinical trial was to determine whether the implanted cells caused any harm. So far, neither patient has experienced inflammation, an indication that their immune system is not attacking the foreign cells.

And there is no evidence that a teratoma formed in either patient. Researchers also found that the RPE cells still survive after being implanted four months ago.

NOT A CURE FOR THE BLIND
The goal of the study was to determine safety and, at most, see whether the therapy can slow down or arrest vision loss, not restore it. "The fact that we're seeing measurable improvements in their vision, persisting for more than four months, is a bonus," Lanza said in an interview.

Although rods and cones cannot be brought back from the dead, he explains, "until you lose them completely you can rescue them." He believes that the transplanted RPE cells both bathed the deteriorating rods and cones in nourishing growth factors and gobbled up fragments of dead rods and cones, keeping the retinal environment healthier for the survivors.

The UCLA physicians plan to enroll a total of 12 Stargardt's patients and 12 macular degeneration patients in the ongoing clinical trial, with groups of three patients each receiving a different number of retinal epithelial cells.

The two patients being reported on Monday each received the smallest dose, 50,000 cells. Other patients will receive at least twice that many. The trial is also expanding across the Atlantic: the first patient was treated at Moorfields Eye Hospital in London last Friday. In a later trial, they hope to treat patients with earlier-stage disease, before so much of their vision has been lost.

David Prentice of the Family Research Council, a pro-life group that has opposed the use of human embryos for research, says the results will require more scrutiny.

"You have to follow the patients longer to know if it's safe," he told Reuters. "People will also want to know if there are other routes to the same end," using sources of stem cells other than human embryos.

Lanza is planning just that. He believes that skin cells "re-programmed" to revert to embryonic status might prove just as good a source or RPE and other specialized cells as human embryonic stem cells.

Called IPS (for "induced pluripotent stem") cells, they can be derived from a patient's own skin cells and pose no risk of immune rejection.

"I think we can be up and running in the clinic with IPS cells in one or two years," Lanza says.

Reversing age-associated effects in MS patients

New research highlights the possibility of reversing ageing in the central nervous system for multiple sclerosis (MS) patients.

The study is published today, 06 January, in the journal Cell Stem Cell.

As we get older, our bodies' ability to regenerate decreases. This is not only true for our skin (which is evident in the wrinkles that develop as we age) but also true for other tissues in the body, including the regenerative processes in the brain.

For diseases which often span several decades and are affected by regenerative processes, such as multiple sclerosis, this can have massive implications.

In multiple sclerosis, the insulating layers that protect nerve fibres in the brain, known as myelin sheaths, become damaged.

The loss of myelin in the brain prevents nerve fibres from sending signals properly and will eventually lead to the loss of the nerve fibre itself.

However, early in the disease, a regenerative process, or remyelination, occurs and the myelin sheaths are restored. Unfortunately, as people with MS age, remyelination decreases significantly, resulting in more nerve fibres being permanently lost.

However, a new study in mice shows that the age-associated decline in the regeneration of the nerve's myelin sheath, or remyelination, is reversible.

The proof of principle study demonstrates that when old mice are exposed to the inflammatory cells (called monocytes) from young mice, the ageing remyelination process can be reversed.

Professor Robin Franklin, Director of the MS Society's Cambridge Centre for Myelin Repair at the University of Cambridge, said: "What we have shown in our study, carried out in collaboration with Dr Amy Wagers and colleagues at Harvard University, is that the age-associated decline in remyelination is reversible.

We found that remyelination in old adult mice can be made to work as efficiently as it does in young adult mice.

"For individuals with MS, this means that in theory regenerative therapies will work throughout the duration of the disease.

Specifically, it means that remyelination therapies do not need to be based on stem cell transplantation since the stem cells already present in the brain and spinal cord can be made to regenerate myelin - regardless of the patient's age."

MS affects approximately 100,000 people in the United Kingdom, 400,000 in the United States and several million worldwide. Symptoms of the disease can include the loss of physical skills, sensation, vision, bladder control, and intellectual abilities.


More information: The paper 'Rejuvenation of regeneration in the aging central nervous system' will be published in the 06 January edition of Cell Stem Cell.

Researchers identify seventh and eighth bases of DNA

For decades, scientists have known that DNA consists of four basic units -- adenine, guanine, thymine and cytosine. Those four bases have been taught in science textbooks and have formed the basis of the growing knowledge regarding how genes code for life. Yet in recent history, scientists have expanded that list from four to six.

Now, with a finding published online in the July 21, 2011, issue of the journal Science, researchers from the UNC School of Medicine have discovered the seventh and eighth bases of DNA.

These last two bases -- called 5-formylcytosine and 5 carboxylcytosine -- are actually versions of cytosine that have been modified by Tet proteins, molecular entities thought to play a role in DNA demethylation and stem cell reprogramming.

Thus, the discovery could advance stem cell research by giving a glimpse into the DNA changes -- such as the removal of chemical groups through demethylation -- that could reprogram adult cells to make them act like stem cells.

"Before we can grasp the magnitude of this discovery, we have to figure out the function of these new bases," said senior study author Yi Zhang, Ph.D., Kenan Distinguished Professor of biochemistry and biophysics at UNC and an Investigator of the Howard Hughes Medical Institute. "Because these bases represent an intermediate state in the demethylation process, they could be important for cell fate reprogramming and cancer, both of which involve DNA demethylation."

Much is known about the "fifth base," 5-methylcytosine, which arises when a chemical tag or methyl group is tacked onto a cytosine. This methylation is associated with gene silencing, as it causes the DNA's double helix to fold even tighter upon itself.

Last year, Zhang's group reported that Tet proteins can convert 5 methylC (the fifth base) to 5 hydroxymethylC (the sixth base) in the first of a four step reaction leading back to bare-boned cytosine. But try as they might, the researchers could not continue the reaction on to the seventh and eighth bases, called 5 formylC and 5 carboxyC.

The problem, they eventually found, was not that Tet wasn't taking that second and third step, it was that their experimental assay wasn't sensitive enough to detect it. Once they realized the limitations of the assay, they redesigned it and were in fact able to detect the two newest bases of DNA. The researchers then examined embryonic stem cells as well as mouse organs and found that both bases can be detected in genomic DNA.

The finding could have important implications for stem cell research, as it could provide researchers with new tools to erase previous methylation patterns to reprogram adult cells.

It could also inform cancer research, as it could give scientists the opportunity to reactivate tumor suppressor genes that had been silenced by DNA methylation.

Shuttle Atlantis Carried Adult Stem Cells Into Space

On its 135th and final flight in NASA's shuttle program, the shuttle Atlantis carried the stem cells of six adults to the International Space Station. Alberto Sant Antonio, MD, a Weston, Florida general surgeon, was selected to obtain the tissue samples from the six adults.

NASA is hopeful the Human adult stem cell experiments will lead to the reversal of the rapid aging process that zero gravity has on astronauts.

"The stem cell research being conducted now will benefit all of us in the future," said Dr. Sant Antonio. "I am confident that NASA's stem cell experiments will help astronauts stay younger and healthier in space, and this will eventually apply to people here on earth.

Dr. Sant Antonio has for the past two years submitted specimens for NASA's evaluation. Not until the final shuttle mission did the adult stem cells end up in space. "NASA came through in a huge way," said Dr. Sant Antonio. "Astronauts age much more quickly because of harmful gamma rays that bombard their bodies. Injecting future astronauts may slow the aging process in space. This is a critical step in space exploration. This is history in the making."

Read More: Atlantis Carries Adult Stem Cells Into Space

First human trials for stem cell blindness therapy

The pioneering treatment could help people losing their sight due to Stargardt, a currently untreatable disease that is one of the most common forms of youth blindness

Photo: GETTY

The first human trials of a stem cell therapy for an eye disease that causes blindness in young people could start next year (2010).

The pioneering treatment could help people losing their sight due to Stargardt, a currently untreatable disease that is one of the most common forms of youth blindness.

Studies on rats and mice have found that the therapy prevents further vision loss without adverse side effects, and the firm behind the breakthrough has now applied to US authorities to test it on humans.

The treatment would consist of a single injection of retinal cells derived from embryonic stem cells left over from IVF treatment.

"After years of research and political debate, we're finally on the verge of showing the potential clinical value of embryonic stem cells," said Robert Lanza, the chief scientific officer at Advanced Cell Technology, the firm which developed the therapy. "The field desperately needs a big clinical success."

The trials would involve 12 Stargardt patients currently losing their sight, and could begin early in 2010 if the Food and Drug Administration grants approval.

Embryonic stem cell research has been controversial because human embryos are destroyed in order to obtain the cells capable of developing into almost every tissue of the body but it also holds great promise for treating cancer, diabetes, Alzheimer's and other diseases.

Rogue Stem cell clinic raided by police

Stem cell tourism – patients paying for treatment at illegal "guerrilla" clinics – continues to be a lucrative racket. Police in Hungary last week arrested four individuals they suspect of running an illegal stem cell treatment clinic in Budapest.

Reuters reported the police saying that the treatments were unproven, based on stem cells taken from embryos or aborted fetuses, and cost as much as $25,000 per person.

Gabor Bucsek, leading the police investigation, was quoted as saying that the arrests were "on suspicion of a banned use of the human body".

The Health Ministry issued a brief statement saying that no institutions in the country have permission at present to carry out stem cell treatment, and only Hungary's Healthcare Scientific Council has authority to issue permission to conduct research. At least eight patients had been treated, although some bloggers report that there may have been as many as 100.

Unproven treatments

Stem cell researchers alarmed by the reports from Hungary praised the police action.

"If the people that have been arrested have done something illegal their arrest is good news," says Robin Lovell-Badge of the National Institute of Medical Research in London.

"I hope it scares others from offering untested treatments and will be a cautionary tale to members of the public," added Lovell-Badge, urging them to consult global guidelines issued last year by the International Society for Stem Cell Research.

Stem cell therapy is promising, but there are major hurdles to overcome, not least the risk of the cells causing cancer.

"There's no proven benefit of any of the treatments on offer at commercial clinics, and there's risks of infection, not getting the stem cells at all, or them growing into something you don't want," says Stephen Barrett, a retired psychiatrist in Chapel Hill, North Carolina, who runs the Quackwatch website. "So to go for treatment is a very foolish thing to do."