Stem Cell Potential Grows

A number of recent publications have added to scientists' understanding of embryonic stem cell (ESC) differentiation and adult stem cell plasticity. For example, Ron McKay and coworkers at the National Institute of Neurological Disorders and Stroke, demonstrated that they can direct murine ESCs to differentiate into a particular type of dopamine-producing neuron, which could aid in the treatment of Parkinson disease.1 Transplantation of stem cell precursors derived from the fetal midbrain leads to functional recovery in animal models of Parkinson, explains McKay, but researchers' ability to grow these cells in the laboratory is limited. "A solution to that problem would be to start with the embryonic stem cell, because [it] can essentially be expanded in the lab without limit," says McKay. "If you could get the right kind of dopamine neuron from an embryonic stem cell, ... it would show for the first time that you could really use stem ...