Type 2 cytokines act on enteric sensory neurons to regulate neuropeptide-driven host defense [RNA-Seq]
Enteric nervous system (ENS)-derived neuropeptides modulate immune cell function, yet our understanding of how inflammatory cues directly influence enteric neuron responses during infection is considerably lacking. Here, we characterize a primary enteric sensory neuron (PSN) subset that produces the neuropeptides neuromedin U (NMU) and calcitonin gene-related peptide beta (CGRPß) and co-expresses receptors for the type 2 cytokines IL-4 and IL-13. Type 2 cytokines were sufficient to upregulate NMU and CGRPß expression in PSNs, in vitro and in vivo, which was abrogated by PSN-specific Il13ra1 deletion. Importantly, PSN-specific Il13ra1 deletion impaired host defense to the gastrointestinal helminth H. polygyrus, diminished enteric sensory neuron populations, and blunted muscularis immune responses. Co-administration of NMU23 and CGRPß rescued helminth clearance deficits and restored anti-helminth immunity. Mechanistically, we show that CGRPß signaling synergizes with IL-4 in intestinal macrophages, inducing alternatively-activated macrophage defense responses, altogether illustrating the critical role of bi-directional neuro-immune crosstalk in regulating intestinal type 2 immunity. Overall design: Bulk RNA-seq was performed on FACS-purified muscularis and lamina propria (LP) ILC2s from the ilea of Calb2-cre; Il13ra1 flox/flox (Calb2?Il13ra1) cKO mice (n = 4) and littermate control Il13ra1 flox/flox mice (n = 5) infected with H. polygyrus (7 days post-infection)