Mucosal-associated invariant T cell
From Wikipedia, the free encyclopedia
Mucosal-associated invariant T cells (MAIT cells) make up a subset of T cells in the immune system that display innate, effector-like qualities.[1][2] In humans, MAIT cells are found in the blood, liver, lungs, and mucosa, defending against microbial activity and infection.[1] The MHC class I-like protein, MR1, is responsible for presenting bacterially-produced vitamin B2 and B9 metabolites to MAIT cells.[3][4][5][6] After the presentation of foreign antigen by MR1, MAIT cells secrete pro-inflammatory cytokines and are capable of lysing bacterially-infected cells.[1][6] MAIT cells can also be activated through MR1-independent signaling.[6] In addition to possessing innate-like functions, this T cell subset supports the adaptive immune response and has a memory-like phenotype.[1] Furthermore, MAIT cells are thought to play a role in autoimmune diseases, such as multiple sclerosis, arthritis and inflammatory bowel disease,[7][8] although definitive evidence is yet to be published.