Human Mucosa-Associated Invariant T Cells Accumulate in Colon Adenocarcinomas but Produce Reduced Amounts of IFN-γ.

摘要: Mucosa-associated invariant T (MAIT) cells are innate-like with a conserved TCR α-chain recognizing bacterial metabolites presented on the MHC-related 1 molecule. MAIT present in intestinal tissues and liver, they rapidly secrete IFN-γ IL-17 response to insult. In colon cancer, IL-17-driven inflammation promotes tumor progression, whereas production is essential for antitumor immunity. Thus, tumor-associated may affect immune responses by their secreted cytokines. However, knowledge of cell presence function tumors virtually absent. this study, we determined frequency, phenotype, functional capacity adenocarcinomas unaffected lamina propria. Flow cytometric analyses showed significant accumulation tissue, irrespective stage or localization. Colonic displayed an activated memory phenotype expression chemokine receptors CCR6 CCR9. Most produced IFN-γ, only few IL-17. also TNF-α, IL-2, granzyme B. tumors, significantly lower frequencies IFN-γ-producing were seen, there no differences other cytokines analyzed, vitro studies that factors from tissue reduced cells. conclusion, infiltrate but ability produce substantially reduced. We suggest have promote local microenvironment act reduce production.