Influence of granulocyte-colony stimulating factor combined with adrenocortical steroid and/or immunosuppressants on immune system of donor mice during hematopoietic stem cell mobilization

Objective:To explore the influence of granulocyte-colony stimulating factor(G-CSF) combined with adrenocortical steroid and/or immunosuppressants on immune system of donor mice during hematopoietic stem cell mobilization.Methods: The donor C57BL/6 mice were divided into 4 groups according to the mobilization strategies,namely,the G-CSF group((250 μg/kg) for 4 days),G-CSF(250 μg/kg for 4 days) + methylprednisolone group(100 mg/kg on day 3),G-CSF((250 μg/kg) for 4 days) + methylprednisolone group(100 mg/kg on day 3) + cyclosporine A(100 mg/kg on day 3),and PBS control group.The post-mobilization T lymphocytes of C57BL/6 mice and the splenocytes of BALB/c mice were subjected to mixed lymphocyte reactions(MLR).The levels of IFN-γ,IL-4,and TGF-β_(1) were determined in the supernatants of donor mice splenocytes by ELISA method and the mRNA levels of IFN-γ and IL-4 were determined by RT-PCR.Results: The results showed that the MLR-inhibitory activities in the 3(G-CSF) mobilized groups were 42%,21%, and 39%,respectively;all lower than that in PBS control group(68%).IFN-γ levels in the 3 G-CSF mobilized groups were lower than that in PBS control group,but he levels of IL-4 and TGF-β_(1)were significantly higher than those in PBS group(P0.01),with no significant difference found between the 3 (G-CSF) mobilized groups.RT-PCR analysis found that the expression of IFNγ mRNA was obviously decreased and the expression of IL-4 was obviously increased(P0.01).Conclusion: G-CSF combined with adrenocortical steroid and/or immunosuppressants can decrease the allogenic reaction of T lymphocytes and change the types of secreted cytokines in donor mice during hematopoietic stem cell mobilization,which may induce immune resistance in the recipients.