Markers of Adult Tissue-Based Stem Cells

The expectation generated by the pluripotentiality of embryonic stem (ES) cells has initiated a renaissance in stemcell biology.While ES cells can be harvested in abundance and appear to be the most versatile of cells for regenerative medicine, adult stem cells also hold promise, but the identity and subsequent isolation of these comparatively rare cells remainsproblematic in most tissues, perhapswith thenotable exceptionof the bonemarrow. Identifying surface molecules (markers) that would aid in stem cell isolation is thus a major goal for stem cell biologists.Moreover, the characterization of normal stem cells in specific tissuesmay provide a dividend for the treatment of cancer. There is a growing belief that the successful treatment of neoplastic disease will require specific targeting of the cancer stem cells, cells that may well have many of the characteristics of their normal counterparts.