Type 2 innate lymphoid cells in the induction and resolution of tissue inflammation

Summary Type 2 immunity against pathogens is tightly regulated to ensure appropriate inflammatory responses that clear infection and prevent excessive tissue damage. Recent research has shown that type 2 innate lymphoid cells ( ILC 2s) contribute to steady‐state tissue integrity and exert tissue‐specific functions. However, upon exposure to inflammatory stimuli, they also initiate and amplify type 2 inflammation by inducing mucus production, eosinophilia, and Th2 differentiation. In this review, we discuss the regulation of ILC 2 activation by transcription factors and metabolic pathways, as well as by extrinsic signals such as cytokines, lipid mediators, hormones, and neuropeptides. We also review recent discoveries about ILC 2 plasticity and heterogeneity in different tissues, as revealed partly through single‐cell RNA sequencing of transcriptional responses to various stimuli. Understanding the tissue‐specific pathways that regulate ILC 2 diversity and function is a critical step in the development of potential therapies for allergic diseases.