“Latest Stem Cells News”

The great promise of induced pluripotent stem cells is that the all-purpose cells seem capable of performing all the same tricks as embryonic stem cells, but without the controversy.

However, a new study published this week (Feb. 15) in the Proceedings of the National Academy of Sciences comparing the ability of induced cells and embryonic cells to morph into the cells of the brain has found that induced cells — even those free of the genetic factors used to program their all-purpose qualities — differentiate less efficiently and faithfully than their embryonic counterparts.

The finding that induced cells are less predictable means there are more kinks to work out before they can be used reliably in a clinical setting, says Su-Chun Zhang, the senior author of the new study and a professor in the University of Wisconsin-Madison School of Medicine and Public Health.

Howard Hughes Medical Institute (HHMI) scientists have discovered that endothelial cells, the building blocks of the vascular system, keep blood stem cells dividing healthily in a lab dish much longer and more effectively than previous methods of growing the cells. The new advance dramatically improves scientists’ ability to manufacture large quantities of authentic adult blood stem cells, which may help revolutionize the field of bone marrow transplantation.

Shahin Rafii, an HHMI investigator at Weill Cornell Medical College in New York City, and his colleagues report on the development of an endothelial cell platform that supports self-renewal of the blood stem cells, known as long-term hematopoietic stem cells (LT-HSCs), in the March 2010 issue of the journal Cell Stem Cell. Their study also describes a novel mechanism by which endothelial cells support propagation of LT-HSCs in adult mice.

Scientists have developed a new tool that illuminates connections between stem cells and cancer.
Researchers have been successful in breaking apart human prostate tissue, extract the stem cells in the tissue, and alter those cells genetically so that they spur cancer.

Many tissues contain pools of stem cells that replenish the tissue when it’s damaged or when changes take place. For example, stem cells in the skin produce new cells to replace those irreparably damaged by the sun, and stem cells in the breast create milk-producing cells when a woman is pregnant.

A characteristic of these stem cells is that they self-renew. This means that in addition to making cells with a specific function, they also make many new stem cells.

The team at Children’s Hospital Boston and the Harvard Stem Cell Institute were working with a new type of cell called induced pluripotent stem cells or iPS cells, which closely resemble embryonic stem cells but are made from ordinary skin cells.

In this case, they wanted to study a rare, inherited premature aging disorder called dyskeratosis congenita. The blood marrow disorder resembles the better-known aging disease progeria and causes premature graying, warped fingernails and other symptoms as well as a high risk of cancer.

One of the benefits of stem cells and iPS cells is that researchers can make them from a person with a disease and study that disease in the lab. Harvard’s Dr. George Daley and colleagues were making iPS cells from dyskeratosis congenita patients to do this (…)

Cells from people with premature aging disease get “younger” with the help of stem cell technology.

Premature aging is one of the most difficult-to-deal with conditions in the world. In addition to its physical consequences, its psychological impact is devastating on a person suffering from it. At this point, experts believe that the disease is caused by the fact that people predisposed to it have very short telomeres, which are repetitive stretches of DNA attached to the end of each chromosome in each cell featuring genetic material in the human body. As chromosomes multiply, the telomeres naturally get shorter, and scientists believe that this may be playing a role in aging.

Korean scientists are moving closer to cloning embryonic stem cells, the unprecedented breakthrough that their compatriot and disgraced scientist Hwang Woo-suk claimed to have achieved in 2004, only to have this disproved later.

Currently, a team at the Cha Medical Center is working on a project after getting state approval last year, while another team headed by professor Park Se-pill at Jeju National University is also set to begin research.
Park and his associates are awaiting final approval from the National Bioethics Committee.

“If the endorsement is made before June, we should be able to clone human embryonic stem cells sometime next year,” said Park, who extracted stem cells from human embryos, not cloned ones, in 2000.
“Our embryologists’ technology is leading on the global scene. Hence, I believe that Korean teams should be able to create cloned embryonic stem cells in the not-so-distant future,” he said.