Nociceptor sensory neurons suppress neutrophil and ᵞδ T cell responses in bacterial lung infections and lethal pneumonia

Baral, Pankaj; Umans, Benjamin D; Li, Lu; Wallrapp, Antonia; Bist, Meghna; Kirschbaum, Talia; Wei, Yibing; Zhou, Yan; Kuchroo, Vijay K; Burkett, Patrick R; Yipp, Bryan G; Liberles, Stephen D; Chiu, Isaac M

Lung-innervating nociceptor sensory neurons detect noxious or harmful stimuli and consequently protect organisms by mediating coughing, pain, and bronchoconstriction. However, the role of sensory neurons in pulmonary host defense is unclear. Here, we found that TRPV1(+) nociceptors suppressed protective immunity against lethal Staphylococcus aureus pneumonia. Targeted TRPV1(+)-neuron ablation increased survival, cytokine induction, and lung bacterial clearance. Nociceptors suppressed the recruitment and surveillance of neutrophils, and altered lung ᵞδ T cell numbers, which are necessary for immunity. Vagal ganglia TRPV1(+) afferents mediated immunosuppression through release of the neuropeptide calcitonin gene–related peptide (CGRP). Targeting neuroimmunological signaling may be an effective approach to treat lung infections and bacterial pneumonia.