Scientists identifies gene that regulates blood-forming fetal stem cells

In the rancorous public debate over federal research funding, stem cells are generally assigned to one of two categories: embryonic or adult. But that’s a false dichotomy and an oversimplification. A new University of Michigan study adds to mounting evidence that stem cells in the developing fetus are distinct from both embryonic and adult stem cells.

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Researchers create genetically matched embryonic stem cells for transplantation

Researchers at Children’s Hospital Boston report a new and efficient strategy, using eggs alone, for creating mouse embryonic stem cells that can be transplanted without the risk of rejection because the cells are compatible with the recipient’s immune system. The findings are published online in the journal Science on December 14.

Though done in mice, the work establishes the principle of using unfertilized eggs as a source of customized embryonic stem cells that are genetically matched to the egg donor at the genes that control recognition of cells by the immune system, making them potentially useful for transplantation therapies. There are several caveats, including the fact that only females could benefit from this technique, donating their own eggs to generate the stem cells, and concerns that the tissues derived from this special type of embryonic stem cells might not function normally.

Scientists provide insights into how the immune system avoids attacking itself

finding by University of Pennsylvania School of Medicine researchers about how immune cells “decide” to become active or inactive may have applications in fighting cancerous tumors, autoimmune diseases, and organ transplant rejection. Pathology and Laboratory Medicine Professor Gary A. Koretzky, MD, PhD, director of the Signal Transduction Program at Penn’s Abramson Family Cancer Research Institute describes, in the current issue of Nature Immunology, one way in which T cells may develop tolerance to host cells and proteins. Koretzky and colleagues found that small fatty acids called diacylglycerols (DAGs), and the enzymes that metabolize them, are critical players in the molecular pathway that leads to activity versus inactivity.

Landmark study of islet transplantation reveals potential benefits in uncontrolled type 1 diabetes

The results of the world’s first multicenter clinical trial of islet transplantation have confirmed the technique’s potential benefits in patients with difficult-to-control type 1 (or “juvenile”) diabetes. Published in the September 28, 2006 issue of the New England Journal of Medicine, the international team of investigators report that the Edmonton Protocol for islet transplantation can safely and successfully promote long-term stabilization of blood sugar levels in “brittle” diabetes patients and in some cases, relieve them of the need for insulin injections altogether for at least two years.