MR1-restricted MAIT cells are a T cell subset that recognize infection by a broad array of microbial pathogens important to human health, including respiratory pathogens like Mycobacterium tuberculosis (Mtb). MAIT cells are defined by the use of a semi-invariant T cell receptor which recognizes microbial small molecules derived from the riboflavin biosynthesis pathway presented on the HLA-Ib molecule MR1. Upon activation, MAIT cells have effector capacity that has been associated with the control of intracellular infection with Mtb (IFN-γ, TNF, and cytolytic capacity). Murine models of infection have shown that MAIT cells are important in the first days of an infection, and in shaping the subsequent adaptive immune response. At present, whether MAIT cells play a unique role in human pulmonary defense is unknown. Here we use whole-transcriptome RNA-sequencing to map the phenotype and function of MAIT cells in human lungs and blood. We map distinct gene sets unique to MAIT cells in comparison to conventional CD8⁺ T cells in each tissue. We anticipate that these gene sets will provide our field with a comparative MAIT cell transcriptome resource library. Here, we identify unexpected gene expression associated with antibacterial immunity that have not been previously associated with CD8⁺ T cells. We use controlled ex vivo assays to validate significant protein expression and analyze mycobacterial growth inhibition. Using an MR1/Ag-tetramer, we characterize the in situ organization of MAIT cells in the human respiratory tract. Our data suggest that mucosal MAIT cells form a functionally distinct subtype in comparison to those in the blood. We postulate that MAIT cells have additional antibacterial capabilities than conventional CD8⁺ T cells and serve as a targeted immune defense barrier at the mucosal interface. Our study highlights the relevance of analyzing human cell function at barrier tissues as an exploration into the breadth of antibacterial immunity.