(Immunity 2025, cover story)
Emerging studies reveal that neurotransmitters and neuropeptides play critical roles in regulating anti-helminth immune responses, hinting at the potential of intrinsic enteric neurons (iENs) in orchestrating intestinal immunity. Whether and how iENs are activated during infection and the potential neuroimmune interactions involved remain poorly defined. Here, we found that helminth infection activated a subset of iENs. Single-nucleus RNA sequencing (snRNA-seq) of iENs revealed alterations in the transcriptional profile of interleukin (IL)-13R+ intrinsic primary afferent neurons (IPANs), including the upregulation of the neuropeptide β-calcitonin gene-related peptide (CGRP). Using genetic mouse models and engineered viral tools, we demonstrated that group 2 innate lymphoid cell (ILC2)-derived IL-13 was required to activate iENs via the IL-13R, leading to iEN production of β-CGRP, which subsequently inhibited ILC2 responses and anti-helminth immunity. Together, these results reveal a previously unrecognized bi-directional neuroimmune crosstalk in the intestine between a subset of iENs and ILC2s, which influences pathogen clearance.
(JACI 2024)
Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are life-threatening drug-induced skin reactions traditionally attributed to CD8⁺ T cell–mediated keratinocyte death. In this study, we reveal a crucial role for neural elements in enhancing the immune response. Using single-cell RNA sequencing and functional assays, we showed that CD8⁺ T cells from SJS/TEN patients upregulate RAMP1, the receptor for the neuropeptide CGRP, and respond more strongly to inflammatory cytokines IL-15 and IL-18. Affected skin exhibits increased CGRP+ nerve fibers, elevated CGRP levels, and enhanced cytotoxic activity of CD8⁺ T cells, which is dependent on calcium influx mediated by the HCN2 ion channel. These findings highlight a neuroimmune axis that promotes tissue damage in SJS/TEN and suggest new therapeutic targets for severe cutaneous drug reactions.