Human stem cells may heal diabetic ulcers

Podiatry Now, August, 2009

SCIENTISTS IN BRISTOL have found that human foetal stem cells can effectively treat back leg ischaemic ulcers in a model of type 1 diabetes.

The researchers found that the culture in which the stem cells have been grown mimicked the wound-healing ability of the cells, suggesting that they could be used as a factory of wound-healing substances. Alternatively, the active ingredients in the culture once identified could be used instead, which would avoid the ethical concerns of using human foetal stem cells.

The healing activity of stem cells is recognised for the ability to separate into various component cells of injured tissues as well as to discharge growth factors that may encourage the formation of new blood cells in the patient.

Paolo Madeddu, Professor of Experimental Cardiovascular Medicine, and colleagues at the Bristol Health Institute previously used stem cells in models of back leg ischaemia, showing that foetal stem cells could be more therapeutically effective than adult stem cells. They have a more effective ability to multiply and to graft onto host tissue and to separate into other cell types to replace those in the damaged tissue. The scientists found that the foetal stem cells accelerate the closure of ischaemic diabetic ulcers while stem cells from blood of adult donors are ineffective.

They discovered that a particular type of stem cell--CD133 cell--promoted blood vessel formation in order to salvage the diabetic limb. Three days following the graft consisting of collagen plus CD133 cells, hardly any CD133 cells were detected in the ischaemic diabetic ulcer, indicating that transplanted cells had done their task in the very first days after transplantation, possibly by boosting the generation of new vessels through an indirect mechanism.

It is known that wounds heal so well in foetuses that no scar can be visible at birth.