Abstract: Objective To investigate the effects of immunospressive drugs supplemented in culture media which provided the microenvironment for the generation of marophages bone marrow progenitor cells (BMPCs) differentiating into macrophages. BR> Methods BMPCs were prepared asepticly from C57BL/6 mice killed by cervical dislocation and EM>in vitro/EM> cultured in the media containing macrophage colony-stimulating factor (M-CSF) and rapamycin (rapa), cyclosporin A (CsA) and paclitaxel respectively. The morphology and phenotype of induced macrophages from BMPCs were analyzed by microscopy and flow cytometry (FCM). Results Induced cells from BMPCs presented specific macrophage morphology. There were high expressions of F4/80 and CD11 in surface molecules of induced macrophages and a dramatically decreased expression of CD11c. However, compared with the control group, there was a significant decrease in counts of differentiating macrophages. There was no significant effect on cell cycle of induced macrophages from BMPCs treated with cyclosporin A and a significant effect on apoptosis of those treated with paclitaxel. BR> Conclusion Three immunosuppressive drugs used in the experiment may affect the development and differentiation of macrophages from BMPCs. BR>

Key words: Rapamycin, Cyclosporin A, Paclitaxel, Bone marrow progenitor cell, Macrophage, Induce, Differentiation, Mouse