A) MHC class Ib-restricted CD8+ T cells, e.g. iNKT cells and MAIT cells, have a faster effector response following infection, compared to MHC class Ia-restricted T cells. B) During chronic infection, microorganisms can employ immunoevasion mechanisms to dampen the classical T cell response and/or NK cell response. MHC class Ib-specific responses could represent a backup system that responds following MHC class Ib upregulation, for example HLA-E.