“Latest Stem Cells News”

Drs. Scott Kitchen, Zoran Galic, Jerry Zack of the UCLA Broad Stem Cell Research Center and AIDS Institute and their colleagues demonstrated for the first time that human blood stem cells can be engineered into cells that can target and kill HIV-infected cells. The process could potentially be used against a range of chronic viral diseases.

The study, published Dec. 7 in the-peer reviewed online journal PLoS ONE, provides proof-of-principle, a demonstration of feasibility, that human stem cells can be engineered into the equivalent of a genetic vaccine.

“We have demonstrated in this proof-of-principle study that this type of approach can be used to engineer the human immune system, particularly the T-cell response, to specifically target HIV-infected cells,” said lead investigator Scott G. Kitchen, assistant professor of medicine in the division of hematology and oncology at the David Geffen School of Medicine at UCLA and a member of the UCLA AIDS Institute. “These studies lay the foundation for further therapeutic development that involves restoring damaged or defective immune responses toward a variety of viruses that cause chronic disease, or even different types of tumors.”

Breast milk, long revered for the nutritional advantages it gives a newborn, could be just as vital in terms of infant development, a leading scientist will claim this week. Up to three different types of stem cells have been discovered in breast milk, according to revolutionary new research.

Dr Mark Cregan, medical director at the Swiss healthcare and baby equipment company Medela, believes the existence of stem cells means breast milk could help a child “fulfil its genetic destiny”, with a mother’s mammary glands taking over from her placenta to guide infant development once her child is born.

“Breast milk is the only adult tissue where more than one type of stem cell has been discovered. That is very unique and implies a lot about the impressive bioactivity of breast milk and the consequential benefits to the breastfed infant,” said Dr Cregan, who is speaking at Unicef’s Baby Friendly Initiative conference this week. His research has isolated adult stem cells of epithelial (mammary) and immune origin, with “very preliminary evidence” that breast milk also contains stem cells that promotes the growth of muscle and bone tissue.

Scientists will use his discovery, made at the University of Western Australia, in Perth, Australia, to attempt to harvest stem cells from breast milk for research on a range of issues – from why some mothers struggle to produce milk to testing out new drugs that could aid milk production. “There is a plentiful resource of tissue-specific stem cells in breast milk, which are readily available and from a non-invasive and completely ethical source,” Dr Cregan said.

Advocates hope the discovery will help to lift the UK’s breastfeeding rates: only one-third of babies are exclusively breastfed at one week, the number dropping to one-fifth at six weeks. At five months, only 3 per cent of mothers still exclusively nurse their babies – although the World Health Organisation recommends that babies should consume only breast milk until they are at least six months old.

Rosie Dodd, campaigns director at the National Childbirth Trust, said: “This finding highlights the many factors that are in breast milk that we know so little about and that all have different advantages, such as helping a baby’s immune system to develop.”

Dr Cregan said the discovery of immune stem cells was the “most exciting development”, adding, “It’s quite possible that immune cells in breast milk can survive digestion and end up in the infant’s circulation. This has been shown to be occurring in animals, and so it would be unsurprising if this was also occurring in human infants.”

British scientists gave a cautious welcome to Dr Cregan’s discovery, warning that just because stem cells exist in breast milk did not mean that they could be used to develop a therapy – the ultimate goal of stem cell research. Chris Mason, professor of regenerative medicine at University College London, said: “It may give us some insight into specific breast diseases and is potentially valuable when it comes to drug discovery and drug development but it is fanciful to think it could provide routine therapies.”

from http://www.independent.co.uk/news/science/stem-cel…hy-breast-is-best-1825558.html

For children born with immunodeficiencies, researchers may have found a better way for them to get the help they need from stem-cell transplants (…)

Children with primary immunodeficiencies have genetic defects in their immune system that leave them open to infection and other complications. Stem-cell transplants can replace the defective immune system with one derived from healthy donor bone marrow, but without a stem-cell transplant, many of these children might die, the researchers noted in a journal news release.

In order to create space for the donor stem cells and prevent rejection, the patient usually undergoes chemotherapy, radiotherapy or both. This chemoradiotherapy can cause severe liver or lung damage, as well as hair loss and sickness. It may also cause problems with growth, puberty and infertility in later life, according to the news release (…)

With this approach, the 16 children with primary immunodeficiencies in this study, who were too sick for a traditional stem-cell transplant, were able to avoid much of the toxicity caused by chemotherapy (…)

read full article on http://www.ajc.com/health/content/shared-auto/healthnews/bird/630592.html

A new experimental therapy to treat diabetes, which involves transplanting embryonic pig stem cells into the diseased tissue, is currently being researched. Experiments have been done on primates, but the results that have been obtained indicate that in the future the same technique could be applied to human beings. For many years, pig organs have been considered the most best match to be used in human transplants, but strong immune reactions and powerful combinations of anti-rejection drugs have always represented an important obstacle in their clinical use.

A study published in the Proceedings of the National Academy of Sciences demonstrates that embryonic tissue from pigs, if transplanted, can form a complete pancreas in the host organism. Yair Reisner and his colleagues say that using an embryonic pancreas in place of an adult pancreas in a transplant encourages the development of the organ and the network of blood vessels that supply and nourish the organ, helping reduce the intensity of the immune response against foreign tissues.

For now, researchers have transplanted embryonic pig pancreases into two groups of monkeys with diabetes, which caused the death of the animals in the first group. An analysis demonstrated that the dose of drugs administered to the first group to suppress the immune response was too high and was lowered in the second group of monkeys. This group survived for almost one year after the transplant.

The key result of this study, say researchers, is that they now understand that the monkeys that received the transplants did not need any insulin for at least four months after the operation. Differently from adult pancreatic tissues, embryonic Langerhans cells have a greater ability to tolerate stress and to regenerate.

Fondazione IRCCS Istituto Nazionale Tumori di Milano

Methods to provide safer stem cell transplants to individuals who are not completely compatible with the donor are being developed. Encouraging results have come from a post-transplant cellular therapy, which strengthens the immune system against viral infections and tumors, developed for the first time at the National Tumor Institute (INT) in Milan. The INT conducted the first phase I-II study in the world, published in ‘Blood’, whose main objective was to assess the use of a low dose radiochemotherapy, followed by low dose post-transplant infusions CD8-depleted donor lymphocytes after a 50% compatible hematopoietic stem cell transplant.

The objective of the study was to reduce transplant toxicity and improve immune system function after the transplant to reduce mortality due to infections and relapses. Stem cell transplants from fully compatible donors (HLA-identical) are an option for many individuals with blood-borne cancers. However, only 50-60% of these patients are able to find a fully compatible donor in their families or on the international donor registry. For leukemia and lymphoma patients with a high risk for early relapse who are not able to find an identical donor, the only concrete alternative is a transplant from a 50% compatible family donor (haploidentical donor) or umbilical cord stem cell transplants for child or low weight patients.

In the past, the use of partially compatible donors was prevented by severe side effects. New strategies to improve results are increasingly necessary. Twenty-eight adult patients affected by advanced hematological neoplasias who had no other alternative treatment in order to survive took part in the study. Twenty-four of the patients were suffering from lymphoma and four from acute leukemia.

Transplant-related mortality after two years was reduced from 40-50% to 25%. The two-year global survival rate was 44% with a better result for patients with chemosensitive diseases (2-year survival rate of 75%).
On the whole, 54 CD8 depleted donor lymphocyte infusions were performed on 23 patients, using three different doses of cells with the objective of defining which dose favored an efficient reconstitution of immunity against infective agents and residual tumor cells, reducing the probability of inducing aggressive immune responses against the recipient. The infusions were well tolerated by the patients and did not reduce the transplant from taking root and did not induce acute toxicity.

A DRUG said to cure diabetes could mean that sufferers will no longer need to take daily insulin injections.
The treatment uses stem cells made from human bone marrow and has been tested on patients suffering from Type 1 diabetes – which affects about 900,000 people in Britain.

Diabetes causes the immune system to attack the pancreas, the organ that makes insulin, which then controls blood-sugar levels.
Sufferers must take insulin injections to stay alive because if blood-sugar levels are allowed to rise too high or get too low, they could fall into a coma and die.
But early trials by American scientists have shown that the drug Prochymal can stop the immune system destroying the pancreas.
It is hoped the drug could be on the market in less than two years.

Professor Aaron Vinik, a hormone specialist in Norfolk, Virginia, said the cure could change diabetes sufferers’ lives.
He said: “This is a very exciting discovery.
Shock “When people get told they have diabetes, it comes as a tremendous shock.
“They have to live with having to take insulin injections for the rest of their lives.

“In future, we will have a cure that will stop the disease in its tracks.”
Prochymal has proved effective because stem cells in the drug form a barrier to protect the pancreas from attack. This allows the organ to recover and to continue making insulin.
The stem cells are taken from volunteers and then multiplied in the lab to produce hundreds of millions of cells.
In early tests, patients have been given three infusions of the cells into their bloodstream over 60 days.

It has been tested on 60 patients with early diabetes.
Those already on insulin were able to reduce the amount as the stem cells started saving the pancreas.
Prof Vinik said most patients would still need insulin at first but would probably be off it “in a matter of months”.

from Daily record