Influence of the transcription factor ROR gamma t on the development of NKp46(+) cell populations in gut and skin

NKp46(+)CD3(-) natural killer lymphocytes isolated from blood, lymphoid organs, lung, liver and uterus can produce granule-dependent cytotoxicity and interferon-gamma. Here we identify in dermis, gut lamina propria and cryptopatches distinct populations of NKp46(+)CD3(-) cells with a diminished capacity to degranulate and produce interferon-gamma. In the gut, expression of the transcription factor ROR gamma t, which is involved in the development of lymphoid tissue-inducer cells, defined a previously unknown subset of NKp46+CD3- lymphocytes. Unlike ROR gamma t(-) lamina propria and dermis natural killer cells, gut ROR gamma t(+)NKp46(+) cells produced interleukin 22. Our data show that lymphoid tissue-inducer cells and natural killer cells shared unanticipated similarities and emphasize the heterogeneity of NKp46(+)CD3(-) cells in innate immunity, lymphoid organization and local tissue repair.