Project description:The somatosensory nervous system surveils external stimuli at barrier tissues, regulating innate immune cells under infection and inflammation. The roles of sensory neurons in controlling the adaptive immune system, and more specifically immunity to the microbiota, however, remain elusive. Here, we identified a novel mechanism for direct neuroimmune communication between commensal-specific T lymphocytes and somatosensory neurons mediated by the neuropeptide calcitonin gene-related peptide (CGRP) in the skin. Intravital imaging revealed that commensal-specific T cells are in close proximity to cutaneous nerve fibers in vivo. Correspondingly, we observed upregulation of the receptor for the neuropeptide CGRP, RAMP1, in CD8+ T lymphocytes induced by skin commensal colonization. Neuroimmune CGRP-RAMP1 signaling axis functions in commensal-specific T cells to constrain Type 17 responses and moderate the activation status of microbiota-reactive lymphocytes at homeostasis. As such, modulation of neuroimmune CGRP-RAMP1 signaling in commensal-specific T cells shapes the overall activation status of the skin epithelium, thereby impacting the outcome of responses to insults such as wounding. The ability of somatosensory neurons to control adaptive immunity to the microbiota via the CGRP-RAMP1 axis underscores the various layers of regulation and multisystem coordination required for optimal microbiota-reactive T cell functions under steady state and pathology.
Project description:The somatosensory nervous system surveils external stimuli at barrier tissues, regulating innate immune cells under infection and inflammation. The roles of sensory neurons in controlling the adaptive immune system, and more specifically immunity to the microbiota, however, remain elusive. Here, we identified a novel mechanism for direct neuroimmune communication between commensal-specific T lymphocytes and somatosensory neurons mediated by the neuropeptide calcitonin gene-related peptide (CGRP) in the skin. Intravital imaging revealed that commensal-specific T cells are in close proximity to cutaneous nerve fibers in vivo. Correspondingly, we observed upregulation of the receptor for the neuropeptide CGRP, RAMP1, in CD8+ T lymphocytes induced by skin commensal colonization. Neuroimmune CGRP-RAMP1 signaling axis functions in commensal-specific T cells to constrain Type 17 responses and moderate the activation status of microbiota-reactive lymphocytes at homeostasis. As such, modulation of neuroimmune CGRP-RAMP1 signaling in commensal-specific T cells shapes the overall activation status of the skin epithelium, thereby impacting the outcome of responses to insults such as wounding. The ability of somatosensory neurons to control adaptive immunity to the microbiota via the CGRP-RAMP1 axis underscores the various layers of regulation and multisystem coordination required for optimal microbiota-reactive T cell functions under steady state and pathology.
Project description:Endometriosis is a debilitating and painful gynecological inflammatory disease affecting approximately 15% of women. Current treatments are ineffective for a significant fraction of patients, underscoring the need for new medical therapies with long-term benefits. Given the relevance of neuroimmune communication in different disease outcomes, we investigated the role of CGRP-mediated neuroimmune communication in endometriosis. We found that mouse and human endometriosis lesions contained CGRP and RAMP1. In mice, nociceptor ablation reduced pain, monocyte recruitment, and lesion size, suggesting that nociceptor activation and neuropeptide release contribute to endometriosis lesion growth and pain. In vitro, CGRP-induced pro-endometriosis macrophages (PEMs) showed impaired efferocytosis and supported endometrial cell growth in a RAMP1-dependent manner. Treatment with FDA-approved drugs that block CGRP-RAMP1 signaling reduced mechanical hyperalgesia, spontaneous pain, and lesion size in mice. Altogether, our data demonstrates the effectiveness, cellular mechanisms and pre-clinical safety of non-hormonal and non-opioid CGRP/RAMP1 blocking therapies, which may lead to clinical benefit for endometriosis patients.
Project description:Peripheral nerves are emerging regulators of the tumor microenvironment, but how sensory innervation shapes breastcancer immunity remains poorly defined. Here we show that triple-negative breast cancers (TNBCs) co-opt nociceptorneurons to suppress antitumor immunity and promote disease progression. Across orthotopic TNBC models, we foundthat primary tumors and tumor-draining lymph nodes were densely innervated by CGRP⁺ sensory fibers. Tumor-derivedcues directly activated dorsal root ganglion neurons, increased calcium responsiveness, induced Ngfr and Atf3, andtriggered release of CGRP and substance P. Mechanistically, a tumor-derived proNGF-NGFR axis reprogrammednociceptors and promoted neuropeptide secretion. Soluble mediators from activated nociceptors suppressed CD8⁺ Tcell-mediated tumor-cell killing, whereas sensory-neuron silencing or ablation curtailed tumor growth and remodeled theimmune microenvironment toward dendritic-cell activation, myeloid reprogramming, and enhanced CD8⁺ T cell and NK-cell effector states. Subset-specific analysis revealed nonredundant sensory control of immune states, with MrgD⁺neurons selectively shaping macrophage-centered programs. Finally, blockade of CGRP signaling through RAMP1 reduced tumor growth and markedly enhanced PD-1 blockade, nearly eliminating primary tumor burden and lungmetastasis in vivo. T cell-specific Ramp1 deletion similarly restrained tumor growth, and RAMP1⁺ CD8⁺ T cells in humanTNBC displayed an exhaustion-associated phenotype. Together, these findings define a tumor-promoting proNGF-nociceptor-CGRP-RAMP1 axis and identify neuroimmune signaling as a therapeuticall
Project description:Innate and adaptive lymphocytes work in concert to maintain tissue homeostasis and to mediate host defense at mucosal barriers. Herein, we used single cell analysis to show substantial diversity of gene expression in ILCs and T helper cells during a helminth infection in the lung. Notably, we found that the Calca gene, which is spliced to generate the neuropeptide CGRP, was selectively transcribed in ILC2s and Th2 cells in an activation dependent manner. The Calca locus acquired chromatin accessibility at the ILC2 precursor stage and is pre-programmed for rapid production of CGRP upon ILC2 activation. CGRP globally antagonized actions of neuromedin U (NMU) and the alarmin IL-33. However, CGRP selectively acted in concert with NMU and IL-33 to promote IL-5 expression, but not IL-13. The complex interplay among neuropeptides and alarmin fine-tunes type 2 immune responses and will undoubtedly become more relevant as therapeutic neuropeptide blockade advances in the clinic.
Project description:Since the immune system plays a critical role in orchestrating tissue healing, regenerative strategies that control immune components have proven effective. This is particularly relevant when immune dysregulation resulting from conditions such as diabetes or advanced age impairs tissue healing following injury. Nociceptive sensory neurons play a crucial role as immunoregulators, exerting both protective and harmful effects depending on the context. However, how neuro-immune interactions impact tissue repair and regeneration after acute injury is unclear. Here, we show that Nav1.8+ nociceptor ablation impairs skin wound repair and muscle regeneration after acute tissue injuries. Nociceptor endings grow into injured skin and muscle tissues and signal to immune cells through the neuropeptide calcitonin gene-related peptide (CGRP) during the healing process. CGRP acts via receptor activity modifying protein 1 (RAMP1) on neutrophils and macrophages to inhibit recruitment, accelerate death, enhance efferocytosis, and polarise macrophages towards a pro-repair phenotype. CGRP effects on neutrophils and macrophages are mediated via thrombospondin-1 release and its subsequent autocrine/paracrine effects. In mice without nociceptors and diabetic mice with peripheral neuropathies, delivering an engineered version of CGRP accelerated wound healing and promoted muscle regeneration. Harnessing neuro-immune interactions holds potential to treat non-healing tissues where dysregulated neuro-immune interactions impair tissue healing.
Project description:Neurogenic inflammation is one component that sculpts the immune milieu of solid tumors. However, it remains unclear how the sensory-neuroimmune axis shapes the immune microenvironment in cold tumors to bolster treatment resistance. Using orthotopic head and neck squamous cell carcinoma (HNSCC) models, we demonstrate that tumor growth-induced sensory hyperexcitability, and surgical sensory signaling interruption reduced tumor growth. Genetic knockout of a key neuropeptide released by sensory neurons, calcitonin gene-related peptide (CGRP), encoded by Calca, produced eradication when paired with multimodal radioimmunotherapy (RT + αPD1). Such treatment reduced Treg infiltration and immunosuppressive function in Calca knockout mice. We also observed that high-dose psilocybin functions as a CGRP inhibitor and transiently reduces tumor growth by increasing antitumor immunity. Additionally, psilocybin increased circulating serotonin, which was partially reversed with platelet activation inhibitor, clopidogrel. We observed differential effects on CD8 and Treg functionality by psilocin in vitro. Correlational analyses in plasma from human subjects following a single-dose psilocybin corroborated these findings. Together, this work underscores the complex interaction of neurogenic inflammation and the tumor immune microenvironment, highlighting potentially new therapeutic avenues for HNSCC and other solid tumors.
Project description:Study of the expression profiles of brain regions (amygdala, hippocampus and cerebral cortex) and trigeminal ganglia collected from rats treated with fremanezumab, an anti-calcitonin gene related peptide (CGRP) mAb, used for the prevention of migraine.