Stem cells in myelotoxicity.

Myelotoxicity describes bone marrow failure due to adverse effect of xenobiotic on hematopoiesis. Hematopoiesis is a complex system in which pluripotent hematopoietic stem cells (PHSCs) differentiate into many highly specialized circulating blood cells involving the interaction of many cell types as well as the interaction of local and systemic growth factors. With respect to blood cell formation, two functional systems must be considered: the hematopoietic stem cells (PHSCs) and the progenitor cells, on one hand, and the stromal cells, which constitute the hematopoietic environment niche, on the other hand. There are three types of assays for hematopoietic progenitor clonogenic assays useable in myelotoxicology: CFU-GM assay for Colony Forming Unit Granulocyte and Macrophage, BFU-E assay for Burst Forming Unit Erythroid, and CFU-MK assay for Colony Forming Unit Megakaryocyte from several species as well as from murine as from mammalian and human. Clonogenic assays have been used to detect myelotoxicity induced by chemicals, drug, food and environmental contaminants. Designs and applications are described in this review.