Specifically, the study found that L. reuteri within melanoma mouse model promotes an immune-stimulatory tumor microenvironment through the release of dietary tryptophan catabolite I3A, which promotes the infiltration of IFNγ-producing CD8+ T cells mediated by AhR signaling, thereby enhancing the response to PD-L1 therapy in patients [104]. Here, CD8A is linked to neoplasm.