A fungi-derived cyclic peptide enhances Th9-mediated antitumor immunity by targeting ZAP70 and SREBP1.

ABSTRACT: Adoptive cell therapy (ACT) relies on durable and functional T cells to mediate tumor clearance. Th9 cells are a metabolically fit CD4+ T cell subset with strong persistence but limited cytotoxicity. Here, we identified endomelipeptide A (EpA), a cyclic peptide isolated from Ganoderma lucidum-associated endophytic fungi, as a potent enhancer of Th9 cell differentiation. EpA promoted a cytotoxic Th9 phenotype with enhanced mitochondrial function and metabolic fitness. Mechanistically, EpA dually targeted ZAP70 and SREBP1, coupling T cell receptor signaling activation with lipid metabolism suppression. EpA-treated Th9 cells mediated robust, CD8+ T cell-dependent tumor control and enhanced the efficacy of human Th9 CAR T cell therapy in vivo. These findings establish EpA as a distinct cyclic

SUBMITTER: Zhao W 

PROVIDER: S-EPMC12867150 | biostudies-literature | 2026 Feb

REPOSITORIES: biostudies-literature