CCR5介导小鼠肝癌微环境中骨髓来源抑制性细胞的迁移

CCR5 gene mediates migration of myeloid-derived suppressor cells in the mouse liver cancer microenvironment

目的探索CCR5在小鼠肝癌微环境中MDSCs迁移的作用。方法建立原位肝癌小鼠模型,流式检测其骨髓来源抑制性细胞(myeloid-derived suppressor cells,MDSCs)水平。分选MDSCs,用CCR5抑制剂100 nmol/L预处理后观察小鼠肝癌细胞H22条件培养基(tumor conditional medium,TCM)及CCR5抑制剂对MDSCs迁移的影响。最后在小鼠肝癌原位模型尾静脉注射DiR标记的CCR5抑制剂处理MDSCs,观察体内肝癌微环境下CCR5抑制剂对MDSCs的迁移影响。结果在原位肝癌小鼠模型中,MDSCs在骨髓、脾、肝中的水平与正常小鼠相比显著性升高;分选得到MDSCs纯度可达94.5%,且MDSCs高表达CCR5。细胞迁移结果显示,CCR5抑制剂能够抑制TCM对MDSCs的募集作用。小动物活体成像结果显示,MDSCs经CCR5抑制剂处理后其在体内向脾和肝迁移的作用也减弱。结论在小鼠肝癌微环境中CCR5介导MDSCs在肿瘤微环境中迁移,抑制MDSCs的CCR5可能为肝癌的临床治疗提供新思路。

Objective To explore the role of CCR5 gene in the migration of myeloid-derived suppressor cells(MDSCs)into the mouse liver cancer microenvironment.Methods A mouse model of orthotopic liver cancer was established and changes in the MDSCs were detected by flow cytometry.To observe the effect of mouse liver cancer cell H22(T-cell)conditional medium(TCM)on the migration of MDSCs,these cells were sorted and pretreated with 100 nmol/L CCR5 inhibitor.Finally,DiR-labeled MDSCs were injected into the tail vein of mice with in situ hepatocarcinoma to observe the effect of the CCR5 inhibitor on the migration of MDSCs in vivo.Results The expression of MDSCs in bone marrow,spleen,and liver was significantly higher in the mouse model of orthotopic liver cancer than that in normal mice.The purity of MDSCs was 94.5%,and MDSCs expressed CCR5.Cell migration result showed that CCR5 inhibitor reduced the recruitment of MDSCs by TCM.The in vivo imaging analysis showed that the ability of MDSCs to migrate to the spleen and liver in vivo was weakened after treatment with CCR5 inhibitor.Conclusions CCR5-mediated MDSCs accumulate in the mouse liver cancer microenvironment.Inhibition of CCR5 in MDSCs may provide a new idea for cancer treatment.