Fig. 1. ATP6V0A1 is required for HFD-induced suppression of anti-tumor immunity.

A Schematic diagram showing an animal model to investigate the significance of CRC cell-derived ATP6V0A1 in the suppression of anti-tumor immunity induced by elevated level of exogenous lipids. B–D C57BL/6 J mice were fed with high-fat diet (HFD) or control diet (CD) for 9 weeks prior to tumor cell implantation, and the body weight was measured (B); using a body-weight randomization grouping approach, HFD mice and CD mice were separately divided into two groups with similar body weights (C) and comparable serum levels of LDL-cholesterol (D). E–H Control MC38 (shNTC) cells or ATP6v0a1-knockdown (shv0a1) MC38 cells were subcutaneously injected to HFD mice and CD mice as shown in (A). Tumor volumes were monitored using calipers, and average tumor growth curves were plotted (E); photographs of the tumors are shown in (F). Tumor-infiltrating lymphocytes (TILs) were isolated and co-cultured with CFSE-labeled MC38 cells, and the cell mixture was analyzed by flow cytometry for the proportion of tumor cell death to assess the killing activities of TILs (G). The relative cytotoxicity of TILs between CD-treated and HFD-treated MC38-shNTC tumors or between CD-treated and HFD-treated MC38-shv0a1 tumors (H) were assessed by calculating the ratio of tumor cell-death proportion (G) between the cell mixture containing TILs from these tumors. For all experiments, data are shown as means ± s.e.m; *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. Statistical significance was determined using ordinary two-way ANOVA (in B, E) or unpaired two-sided Student’s t-test (in C, D, G, H). n = 10 (B), 5 (C–F), or 3 (G, H) mice in each group; Data representative three independent experiments (B–H). Source data and exact p-value are provided as a Source Data file.