摘要髓系来源抑制细胞(MDSC)是髓系来源的一群异质细胞,在荷瘤小鼠模型及肿瘤患者均发挥免疫抑制作用.肿瘤MDSC免疫逃逸作用的机制目前已取得了很多进展,这群细胞可以通过上调精氨酸酶1(ARN1),诱导一氧化氮合酶(iNOS or NOS-2)表达,增加一氧化氮(NO)、活化氧自由基(ROS)等的释放,分解肿瘤微环境中的半胱氨酸、下调T细胞表面L选择素水平并抑制T细胞功能,MDSC还可诱导体内调节性T细胞(Tr)形成、调节固有免疫.此外,MDSC可通过分化为肿瘤相关巨噬细胞(TAM)、分泌Th-2型细胞因子、促进肿瘤血管生成及肿瘤转移等一系列机制促进肿瘤细胞逃避免疫监视.

abstractsMyeloid derived suppressor cells (MDSC) are a group of heterogeneous myeloid cells,which play a role in immune suppression in tumour-bearing mice and cancer patients. MDSC may suppress T cells by upregulating the expression or release of arginase1 ( ARN1 ), inducible nitric oxide synthase ( iNOS or NOS-2), nitric oxide ( NO), reactive oxygen species ( ROS), and disintegrating cysteine in tunour microenvironment, downregulating L-selectin of T cell. In addition, MDSC could enhance immune escape by inducing T regulatory cells, modulating innate immune, differentiating to tumor associated macrophage (TAM), secreting Th-2 type cytokines, or promoting vascular formation of tumor.