Functionally distinct NKT cell subsets and subtypes.

Natural killer T (NKT) cells are a population of autoreactive cells that mediate both protective and regulatory immune functions. NKT cells comprise several subsets of cells, but it has been unclear whether these different NKT cell subsets possess distinct functions in vivo. New studies now demonstrate that subsets of NKT cells are indeed functionally distinct and that the specific functions of these cells may be dictated in part by organ-specific mechanisms.