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: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: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.
Project description:alpha-CGRP is a neuropeptide that is also expressed in the fracture callus during bone regeneration. Our aim was to evaluate the role of alpha-CGRP in the context of fracture healing. Therefore we investigated the effect of alpha-CGRP deficiency on fracture callus formation. We used microarray analysis to compare the global gene expression of fracture calli from alpha-CGRP deficient mice and WT mice.
Project description:We compared the transcriptomes of OSCC cells (Cal27 cell line) with or without treatment of CGRP under different culture conditions.
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:Neuroimmune interactions have emerged as critical modulators of allergic inflammation, and type 2 innate lymphoid cells (ILC2s) are an important cell type for mediating these interactions. Here, we show that ILC2s expressed both the neuropeptide CGRP (Calcitonin Gene-Related Peptide) and its receptor. CGRP potently inhibited alarmin-driven type 2 cytokine production and proliferation by lung ILC2s both in vitro and in vivo. CGRP induced marked changes in ILC2 expression programs in vivo and in vitro, attenuating alarmin-driven proliferative and effector responses. A distinct subset of ILCs scored highly for a CGRP-specific gene signature after in vivo alarmin stimulation, suggesting CGRP regulated this response. Finally, we observed increased ILC2 proliferation and type 2 cytokine production and exaggerated responses to alarmins in mice lacking the CGRP receptor. Together, these data indicate that endogenous CGRP is a critical negative regulator of ILC2 responses in vivo.