mTORC1 controls ILC2 activation and allergic lung inflammation through NMUR1-mediated neuronal regulation [WT-KO ILC2s RNA-seq]
Group 2 innate lymphoid cells (ILC2s) play critical roles in allergic lung inflammation through initiating and amplifying type 2 immune responses. However, the molecular mechanisms underlying pathogenic ILC2 activation remain largely unknown. Here, we show that lung ILC2s exhibit increased mTORC1 activation in allergic asthma. Genetic ablation of RAPTOR, an adaptor protein of the mTORC1 complex, results in reduced IL-5 and IL-13 production in ILC2s and protects mice from allergic inflammation. Pharmacological inhibition of mTORC1 by rapamycin also suppresses ILC2 pathogenic activation and ameliorates allergic lung inflammation. Mechanistically, mTORC1 signaling promotes ILC2 activation through metabolic regulation of epigenetics to maintain neurointerin U receptor 1 (NMUR1) expression, which mediates neural-ILC2 interaction via the NMU-NMUR1 axis. These findings identify mTORC1 as a novel regulator to control the neural-ILC2 interaction and highlight mTORC1 as a potential therapeutic target for allergic asthma. Overall design: lung ILC2s mRNA profiles of  R5/+ (WT) and R5/+Rptorf/f (KO) mice after papain treament