Study on the phenotype and function of CD8+Treg cells induced by ovarian cancer cell / 实用医学杂志

ABSTRACT

Objective To investigate the phenotype and function of CD8+T cells cultured with SK-OV-3. Methods Transwell coculture experiments were conducted in 24-well plates with inner wells to separate CD8+ T cells and SK-OV-3. After 5 days of culture, CD8+ T cells were washed, and 1 × 106 cells were collected for Foxp3, CD25, CD28, CTLA-4 and GITR mRNA analysis and 2 × 106 cells were collected to detect expression of Foxp3, CD25, CD28, CTLA-4 and GITR in CD8+ T cells by flow cytometry. CD8+T cells that cultured alone or with SK-OV-3 were added at ratios of 1∶0 , 1∶1 , 1∶5 , 1∶10 , and 0∶1 to na?ve CD4+ T cells in 96-well plates. All wells were cultured with the presence of irradiated PBMCs and anti-CD3 antibody. After 72 h, [3H]-thymidine was added for 16 h prior to the determination of proliferation by scintillation counting. Results Compared with CD8+ T cells cultured without SK-OV-3 , the expression of Foxp3 and CTLA-4 was increased and CD28 expression was decreased in CD8+ T cells cultured with SK-OV-3 (both P < 0.001). We found that CD8+T cells cultured with SK-OV-3 significantly suppressed the na?ve CD4+ T cell proliferation induced by the anti-CD3 stimulation in a dose-dependent manner. In contrast, CD8+ T cells cultured without SK-OV-3 did not suppress na?ve CD4+ T cell proliferation. Conclusion Ovarian cancer cell can induce the suppressive CD8+Treg, which is an important link of the immunosuppressive microenvironment in ovarian cancer.