Elucidation of the mechanism of immunosuppression by stromal cells and mesenchymal stem cells in ovarian cancer

在这项研究中，我们分析了间充质干细胞（MSC）在癌症微环境中的免疫学作用。在异种移植小鼠模型中，肿瘤组织中浸润了表达类似骨髓间充质干细胞标记物的基质细胞，与不表达MSC标记物的细胞相比，这些基质细胞高表达IL10、COX2、MCP-1、VEGF等免疫抑制分子。此外，MSC也存在于区域淋巴结中，这些MSC的MHC II类表达水平低于非区域淋巴结中的MHC II类表达水平。我们还在人肿瘤组织中检测到表达类似骨髓间充质干细胞标记物的基质细胞。上述结果提示，间充质干细胞可在肿瘤及肿瘤患者局部淋巴结内诱导免疫抑制微环境，可能是修复免疫抑制环境的治疗靶点。

In this study, we analyzed the immunological role of mesenchymal stem cells (MSC) in the cancer microenvironment. In xenografted mouse model, stromal cells expressing markers similar to bone marrow MSC were infiltrated in tumor tissues, and these stromal cells were highly expressed immunosuppressive molecules such as IL10, COX2, MCP-1 VEGF, compared to cells not expressing MSC marker. Further, MSC were also present in the regional lymph nodes and these MSC were expressed lower level of MHC class II than those exsisted in nonregional lymph nodes. We also detected stromal cells expressing markers similar to bone marrow MSC in human tumor tissue. These results indicated that immunosuppressive microenvironment was induced by MSC in tumor and regional lymph nodes of cancer patients, and the MSC may be a therapeutic target for restoration of immunosuppressive environment.