IL17A and chronic obstructive pulmonary disease: In a murine model of COPD, all ILC subsets including T-bet+ ILC1s, ST2+ ILC2s, and RORγt+ ILC3s were increased markedly in the smoking group associated with the level of IFN-γ or IL-17, indicating the prominent role of ILC1s and ILC3s (Blomme et al., 2018).