“Latest Stem Cells News”

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 (…)

UW-Milwaukee researcher Andrew Cohen has successfully developed a software program that facilitates predicting the evolution of stem cells. The program essentially speeds up what has been a tedious process for researchers in the past.

The program was published last week in the journal Nature Methods. It applies algorithmic information theory to the growth and movement of stem cells tracked over time to show what type of cells (i.e. brain, skin, etc.) they will eventually develop into.

“People look at images and take measurements by hand,” Cohen explained. “It takes a long time, and using computers makes the process a lot less tedious.”

Stem cells all start out the same before they develop into the different cells of our bodies. Scientists do not know what triggers the stem cell’s future growth pattern into a particular type of cell, but researchers like Cohen are figuring out how to predict the cell’s future based on measurements and math.

Researchers at Queen Mary, University of London, studied equivalent cells taken from mouse brains. Principal investigator Silvia Marino, Professor of Neuropathology at Queen Mary, University of London, and her team showed that medulloblastomas can grow from a type of brain stem cell and that these cancers are a distinct form of the disease which may require a completely different approach to treatment.

Like a Hole in the Head: Living with a Brain Tumour

Dr. Karen Aboody estimates that she has cured several hundred mice of a cancer of the central nervous system called neuroblastoma.
First she injected them with specialized neural stem cells that naturally zero in on the tumors and surround them. Then she administered an anti-cancer agent that the cells converted into a highly toxic drug (…)

For 3 1/2 years, the agency focused on the basic groundwork needed to someday use human embryonic stem cells to replace body parts damaged by injury or disease. Such cures are still far in the future.
Now the institute has a more immediate goal: boosting therapies that are much further along in development and more often rely on less glamorous adult stem cells. It is concentrating its vast financial resources on projects that could cure conditions such as age-related macular degeneration, AIDS, sickle cell disease and various types of cancer (…)