ES Cells essays

Ideas for My Paper/ ES Cells essays Embryonic stem (ES) cells are considered the ultimate stem cell because of their dual ability to proliferate and to differentiate into all the cells and tissues of the body. But they are ethically contentious because five-day-old embryos have to be destroyed to derive them. Adult stem cells show promise as an ethically preferable alternative, but scientists have not been able to show that they are as versatile as ES cells. The two papers featured in this web focus highlight the promise of both avenues of research, one describing a kind of adult stem cell that may turn out to be just as versatile as ES cells, and the other showing that ES cells can generate neurons to effectively treat symptoms of Parkinson's disease in a rat model. Now, Catherine Verfaillie and her colleagues at the University of Minnesota, Minneapolis, have isolated an adult stem cell from cultured human, rat and mouse bone marrow mesenchymal stem cells, called MAPCs - for mesenchymal adult progenitor cells. Like ES cells, these cells multiply indefinitely in culture. Injected into mouse embryos, the mouse cells differentiate into most, if not all, of the cell types in the body. In a separate paper, Ron McKay and colleagues at the National Institute of Neurological Disorders and Stroke, Bethesda, Maryland, show that mouse ES cells be used in cell replacement therapy in an animal model of Parkinson's disease. From cultured ES cells, the group generated a large supply of neurons that produce dopamine. The neurons functioned normally and gave clear behavioural responses when grafted into the brains of rats that model Parkinson's disease. Together the papers show two different approaches for isolating powerful, pluripotent stem cells with clear therapeutic potential. However many fundamental questions remain about how ES cells and MAPCs function in a biological context, and how they can best be harnessed for medical benefit. It will be exciting to watch the ans ...