查看文章

Myeloid derived suppressor cells (MDSCs) suppress innate and adaptive immunity, thereby limiting anti‐tumor immune responses in cancer patients. In patients with advanced melanoma, the phenotype and function of MDSCs remains controversial. In our study, we further explored two distinct subpopulations of MDSCs and investigated the impact of Vemurafenib on these cells. Flow cytometry analysis revealed that in comparison to healthy donors and patients with localized disease, PBMCs from patients with metastatic melanoma showed an increased frequency of CD14⁺HLA‐DR^−/low monocytic MDSCs (moMDSCs) and of a previously unrecognized population of CD14⁻CD66b⁺Arginase1⁺ granulocytic MDSCs (grMDSCs). In vitro, both populations suppressed autologous T‐cell proliferation, which was tested in CFSE‐based proliferation assays. Vemurafenib treatment of melanoma patients reduced the …