Mucosal Associated Invariant T (MAIT) cells are unconventional T cells present abundantly in human tissues. MAIT cells interact with antigens presented by MR1, an MHC class I protein, to fight microbial infections. They also reportedly activate through cytokines to combat viruses. While MAIT cells exhibit the innate-like characteristic of rapid responses to infections, they also display adaptive-like qualities such as an effector-memory phenotype. Defining the role of MAIT cells in the immune system is essential to understand lung immune responses against bacterial infections. The following protocol outlines the expansion of MAIT cells via a cultured Salmonella Typhimurium BRD509 vaccine strain. Six days after infecting mice retro-pharyngeally with BRD509, MAIT cells were extracted from the lungs. The cells were then enriched and labeled with fluorescence for sorting. Once sorted, MAIT cells were plated and activated with anti-CD3/CD28. The cells were then analyzed with flow cytometry.