The majority of T lymphocytes recognize antigenic peptide fragments presented by MHC
molecules, and this confers antigen specificity to the adaptive immune system. However, a
significant part of T lymphocytes in fact recognize different types of antigenic structures. A
fairly recently discovered T cell subset is the Mucosa-associated Invariant T (MAIT) cells, which
constitutes up to 10% of circulating T cells in human peripheral blood. MAIT cells were
recently shown to recognize microbial vitamin metabolite antigens presented by the highly
conserved MHC class-like molecule MR1. Another type of non-classical T cells is the invariant
Natural Killer T (iNKT) cells that recognize CD1d-presented glycolipids. Despite that MAIT cells
and iNKT cells recognize very different antigenic structures they have their innate-like response
characteristics in common. In our studies we aim to understand the roles that these innate-like
T cell subsets play in infectious diseases.