CD4 and neoplasm: While acetate supplementation did not further improve ICB efficacy in WT tumor-bearing mice, it significantly improved therapeutic effects of ICB in Hif1α− / − tumor-bearing mice, evidenced by potent suppression of tumor growth (Fig. 7E), greatly reduced tumor weights (Fig. 7F), and significantly increased IFN-γ production in Hif1α− / − CD4+ (Fig. 7G) and CD8+ (Fig. S7D) TILs.