Granulocyte-macrophage colony-stimulating factor effectively induces CD14+ HLA-DR-iNOS+ myeloid derived suppressor cells from peripheral blood monocytes / 中华器官移植杂志

ABSTRACT

Objective To investigate the effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) on the generation of human myeloid derived suppressor cells (MDSCs) relied on peripheral blood monocytes,and to establish efficient induction system in vitro of MDSCs.Methods Kidney transplantation recipients between January and March 2017 were included in this study.Purified CD14 + cells isolated from peripheral blood were cultured in the presence of GM-CSF with different concentrations for 7 days.Phenotypes and immunosuppressive abilities of induced MDSCs (iMDSCs) were investigated with FACS analyses.Inducible nitric oxide synthase (iNOS) mRNA expression was detected by qRT-PCR to determine the influence of iNOS-pathway on the immunosuppressive abilities of iMDSCs.Results A total of 11 recipients were included in this study.HLA-DR expression decreased sharply after the culture with GM-CSF.iMDSCs showed the similar phenotype characteristics with monocytic-MDSCs (M-MDSCs) as well as significant ability to suppress T cells proliferation and cytokines production.iMDSCs expressed higher levels of iNOS than monocytes,and the inhibitor effects of iMDSCs were significantly reduced after treatment with L-NMMA (1 mmol/L).The variations of phenotype and suppressive ability were concentrationdependent,and more significant changes could be revealed in the group of 10 μg/L GM-CSF.Conclusion GM-CSF-treated peripheral blood monocytes can be efficiently transformed to M-MDSCs,and suppress T cells proliferation and cytokines secretion via iNOS-dependent pathway.These results may contribute to establish MDSCs induction system,which would provide a basis for the clinical application of MDSCs.