Study of Bone Marrow Niche Cells in Aplastic Anemia and Its Change to Acute Leukemia Possibly

In aplastic anemia bone marrow failure results from severe damage to the hematopoietic cell compartment; In other words, defects in hematopoietic stem cells(HSCs) and the stromal implicate in the disease but cause of this disease is still obscure. Actually imbalance between adipogenic and osteogenic differentiation of mesenchymal stem cell (MSC) can influence hematopoiesis importantly. Cells bearing the CD34 antigen , a marker of early hematopoietic cells, are greatly diminished and in functional studies committed stem cells like CFU-G, CFU-M, CFU-Mk and primitive progenitor cells like CFU-Mix are virtually reduced or absent. These findings suggest that reduced hematopoietic stem cells are the primary defect in abnormal hematopoiesis. Anyhow, we can say aplastic anemia is a stem cell disease firstly and second cytokine deficiency is not the etiologic problem in many cases of aplastic anemia because of some studies have shown relatively normal growth factor production and in some cases of aplastic anemia due to stromal cell defects possibility as well. Thus, here I try to discuss the HSCs and their microenvironment in aplastic anemia which how can support from normal hematopoiesis.