Fig. 4

Tumor-secreted IFI35 promotes CD8⁺ T cells proliferation. A ELISA analysis in the supernatant of IFI35 overexpressed or knocked down CT26 and MC38 cells. B–G Effect of IFI35 protein on T cell migration, apoptosis and proliferation in vitro. T cell migration, apoptosis and proliferation in the presence of supernatant from murine colon cancer cells expressing shRNA against IFI35 (shIFI35) and scrambled sequence control (shRNA) for 72 h. In all experiments, mouse splenic CD8⁺ T cells were stimulated with plate-bound anti-CD3/CD28 mAbs. B, C Migration of CD8⁺ T cells by flow cytometric analysis. D, E Flow cytometric analysis of mouse splenic CD8⁺ T cells apoptosis. F, G Proliferation of CFSE-labeled mouse splenic CD8⁺ T cells by flow cytometric analysis. n = 3. Error bars represent the mean ± SEM. Two tailed t-tests, ns not significant. ***P < 0.001, ****P < 0.0001. H, I Effect of IFI35 on T cell proliferation in vivo. H Gating strategy for Ki67⁺ CD8⁺ T cells in CT26 tumors. I Quantification of Ki67 expression among CD8⁺ T cells in CT26 tumors. n = 4 for both groups. Two tailed t-tests. **P < 0.01