The 3C10 antibody recognizes the Valpha7.2 T cell antigen receptor (TCR) alpha-chain segment which, joined with the Jalpha33 segment, constitutes an invariant TCR that is characteristics of the mucosal-associated invariant T cells (MAIT cells). MAIT cells are restricted by a nonpolymorphic class Ib major histocompatibility complex (MHC) molecule, MHC-related molecule 1 (MR1). MAIT cells are present in human blood (1-8% of T cells), mesenteric lymph nodes, liver, and intestinal mucosa. MAIT cells play a role in detecting and fighting off microbial infections.