The finding both supports the existence of these splenic stem cells and also suggests they may be able to produce an even greater variety of tissues. The report appears in the January 19 issue of SAGE KE (http://sageke.sciencemag.org ), an online resource on the science of aging from the publishers of the journal Science.
"There may be a previously undiscovered pocket of primitive stem cells in the spleen that are important for healing several types of damage or injury," says Denise Faustman, MD, PhD, director of the MGH Immunobiology Laboratory and senior author of the SAGE KE report. "If so, these cells could have much broader therapeutic applications than suggested by our earlier work."
In 2001 Faustman's team found that a treatment designed to address the autoimmune reaction underlying type 1 diabetes actually cured the disease in diabetic mice. Late in 2003 they reported the mechanism behind the earlier discovery: cells from the spleens of donor mice intended to train the diabetic animals' immune systems not to attack islet cells were actually producing new islets. The result suggested that the adult spleen previously regarded as playing a fairly minor role in regenerative medicine might contain a population of potential islet stem cells.
In their pursuit of that finding, the MGH researchers investigated the possible presence of a protein called Hox11 in these cells. In mammals, Hox11 is a controller of key steps in embryonic development including the formatio
Contact: Sue McGreevey
Massachusetts General Hospital