Multifaceted roles of group 2 innate lymphoid cells in respiratory diseases

Group 2 innate lymphoid cells (ILC2s) play a canonical role in the induction of type 2 inflammation by producing type 2 cytokines, including interleukin (IL)-5 and IL-13, in response to stimuli such as IL-33. However, their functions are modulated by tissue- and disease-specific microenvironments, including cytokines, lipid mediators, neuropeptides, and hormones. These influences give rise to diverse ILC2 phenotypes that contribute to non-canonical roles, such as the production of type 1 and type 3 cytokines, thereby expanding their traditional functions. This review examines the multifaceted roles of ILC2s in various respiratory diseases, including asthma, chronic obstructive pulmonary disease, pulmonary fibrosis, lung cancer, and viral infections, and highlights their significant impact on disease pathophysiology. However, the mechanisms underlying ILC2 diversity remain poorly understood. A deeper understanding of this diversity is critical for the development of targeted therapeutic strategies to modulate ILC2 function. By examining the roles of ILC2s in respiratory diseases, this review offers valuable insights into their contribution to disease pathophysiology and potential as targets for innovative therapeutic strategies.