The changes of CD34~+ cells in bone marrow of blood deficiency mice induced by cyclophosphamide

Objective:To observe the changes of CD34 + cells and characterize the cell cycle status of bone marrow cells of blood deficiency mice induced by cyclophosphamide (CTX). Methods:Establishment of the blood deficiency model in mice by injected i.p with CTX. Flow cytometric enumeration of CD34 +hematopoietic stem and progenitor cells by double fluorescent labeling, and cell cycle detection by PI labeling at the indicated detection time. Results:①Compared with normal group, the rate of CD34 + cells in bone marrow nuclear cells decreased at first, then increased for some days, and then decreased. ②Bone marrow cell cycle perturbed after CTX injected, a large fraction of bone marrow cells are relatively more quiescent at first, then are in an actived state and proliferated, then a significant increase in the number of quiescent bone marrow cells. These changes matched those changes of CD34 + cells. Conclusion: CTX mobilize more hematopietic stem and progenitor cells into S/G2/M cycle, and the number of stem and progenitor cells increased, this result in the exhaustion of pool of stem and progenitor cells and a lot of damage to bone marrow. This may be one of causes of blood deficiency induced by CTX.