[Methodologies for isolation, expansion and differentiation of somatic stem cells(tissue stem cells)].

Recent studies have shown that pluriponten stem cells are also found in adult tissue. These adult stem cells has a great advantage over other stem cells sources, human embryos or human fetal tissue, that trouble many people on ethical grounds. While the adult stem cells have great potential for use in the cell therapy, we must pass numerous technical hurdles to reach a goal. Here we describe a subset of problems encountered in isolation and expansion of somatic stem cells for clinical application. As it is necessary to obtain the enough number of cells to supply the defect tissue and organ, we required purification and ex vivo expansion of stem cells, overcoming senescence. We also refer to the argument about plasticity of adult stem cells.