Developments in stem cell transplantation: promises, promises…

Stem cells are simple in structure but have the unique potential to differentiate into any complex cell type. In culture, they self-replicate without limit; they form the early embryo and give rise to all cells in the fetus, the neonate, then to the adult (i.e. they are pluripotent). The term ‘stem cell’ encompasses a diverse group of cell types extending beyond fetal development and even into adult life, when they may lose the ability to differentiate into any body cell type but can give rise to specialized cells. Bone marrow stem cells are examples of multipotent stem cells because they can differentiate into the several cell types of the haemopoietic system. Current knowledge of stem cells and how they might be used for treatment of diseases including Parkinson’s, diabetes, ischaemic injury and muscular disease are summarized in this review.