Drivers of IL-22 secretion

Innate Lymphoid Cells Secretion of the cytokine interleukin-22 (IL-22) by innate lymphoid cells and intestinal T cells in the gut promotes epithelial integrity and provides protection against intestinal pathogens. Bauche et al. investigated which cytokines and signal transducer and activator of transcription (STAT) proteins activate IL-22 production by group 3 innate lymphoid cells (ILC3s) in mice. They found that IL-2, acting through STAT5, contributed to the induction of IL-22 in ILC3s, bolstering the ability of T cell–deficient mice to fend off Citrobacter rodentium infection. IL-23 activated both STAT3 and STAT5 in ILC3s, enabling binding of a STAT3-STAT5 complex to the IL-22 promoter. These studies revealed that ILC3s and T cells use distinct sets of cytokines and STATs to achieve activation of IL-22 expression. Sci. Immunol. 5 , eaav1080 (2020).