Mucosal tissues, lying at the interface with the external environment, are constantly challenged by microbial, physical and chemical assaults. To provide the necessary immune defence to such challenges, lymph nodes and Peyer's patches are formed in utero in response to inductive signals from lymphoid-tissue inducer (LTi) cells. As discussed in this Progress article, a series of recent reports has identified a population of interleukin-22-producing mucosal cells in the gut and tonsils that share features with both LTi cells (by expressing RORγt) and natural killer cells (by expressing NKp46) and that might be involved in immunity and homeostasis in mucosal tissues.

T lymphocyte subpopulation, cell isolation, cytokine production, human, innate immunity, interleukin 17, interleukin 17F, interleukin 22, intestine epithelium cell, lymph node cell, mucosal immunity, natural killer cell, nonhuman, priority journal, protein p46, review, tissue repair, tonsil cell, transcription factor, transcription factor rorc, unclassified drug,
Nature Reviews. Immunology
Erasmus MC: University Medical Center Rotterdam

Vivier, E, Spits, H, & Cupedo, T. (2009). Interleukin-22-producing innate immune cells: New players in mucosal immunity and tissue repair?. Nature Reviews. Immunology (Vol. 9, pp. 229–234). doi:10.1038/nri2522