Project description:Neuroimmune crosstalk is critical for intestinal and tissue homeostasis. Yet the role of molecularly distinct subsets of gut-innervating neurons in regulating the activity of gut immunocytes, and the mechanisms of this neuroimmune signaling remain unclear. Here, we performed a chemogenetic and flow cytometry-based analysis of mice targeting eight different peripheral neuron subsets to assess how gut immunocytes are altered following neural activation. We found that distinct neurons modulated discreet anatomical populations of immunocytes in the gut in ileum, cecum, and colon. Nos1+ neuron activation decreased the percentage of RORg+ ileal conventional CD4+ T cells, whereas ChAT+ neuron activation decreased ileal neutrophils. Trpv1+ neuron activation displayed the most robust immunomodulatory phenotype, causing downregulation of RORg+ T regulatory cells in the colon and cecum. The immune cells exhibited decreased proliferation, enhanced cell stress, and altered cell activation markers. Further genetic and pharmacological approaches showed that spinal afferent Trpv1+ neurons specifically decreased Treg cells by signaling via the neuropeptide CGRP. Our study provided a comprehensive understanding of neuro-immune interactions, revealing a role for mechanisms by which Trpv1+ neurons regulate gut Treg cells.
Project description:To probe molecular distinctions in the specification of motor neurons innervating digit muscles we performed a screen for genetic markers that distinguish digit innervating motor neurons from other motor pools. Here, we compare the gene expression profiles of motor neurons that supply muscles with defined biomechanical functions.
Project description:Using RNA sequencing of FACS sorted retro-labeled sensory neurons innervating tongue tissue, we determined changes in transcriptomic profiles in males and female mice under naïve as well as tongue-tumor bearing conditions Our data revealed the following interesting findings: 1) Naïve female neurons innervating the tongue exclusively expressed immune cell markers such as Csf1R, C1qa and others, that weren’t expressed in males. 2) Male neurons were more tightly regulated than female neurons upon tumor growth; 3) While very few differentially expressed genes (DEGs) overlapped between males and females post-tumor growth, several biological processes (BPs) were similar between two sexes. However, additional distinct processes were sex-specific; 4) Post-tumor growth, male DEGs contained an equal mix of transcription factors, ligands, growth factors, receptors and channels, whereas female DEGs predominantly contained channels/receptors, enzymes, cytokines and chemokines.
Project description:We have generated CRISPR edited versions of hESC line MShef11 to produce MFN2 R94Q/+ and MFN2 R94Q/R94Q lines as a model for Charcot Marie Tooth Disease (CMT) 2A. This were differentiated to limb innervating motor neurons, the predominantly affected cell time in CMT2A and RNA was examined to investigate differences in cell lines.
Project description:Mechanosensory neurons innervating the skin underlie our sense of touch. Fast-conducting, rapidly adapting mechanoreceptors innervating glabrous (non-hairy) skin form Meissner corpuscles, while in hairy skin, they associate with hair follicles, forming longitudinal lanceolate endings. How mechanoreceptors develop axonal endings appropriate for their skin targets is unknown. We report that mechanoreceptor morphologies across different skin regions are indistinguishable during early development but diverge post-natally, in parallel with skin maturation. Neurons terminating along the glabrous and hairy skin border exhibit hybrid morphologies, forming both Meissner corpuscles and lanceolate endings. Additionally, molecular profiles of neonatal glabrous and hairy skin-innervating neurons largely overlap. In mouse mutants with ectopic glabrous skin, mechanosensory neurons form end-organs appropriate for the altered skin type. Finally, BMP5 and BMP7 are enriched in glabrous skin, and signaling through type I bone morphogenetic protein (BMP) receptors in neurons is critical for Meissner corpuscle morphology. Thus, mechanoreceptor morphogenesis is flexibly instructed by target tissues.
Project description:Human pluripotent stem cells are a promising source of diverse cells for developmental studies, cell transplantation, disease modeling, and drug testing. However, their widespread use even for intensely studied cell types like spinal motor neurons, is hindered by the long duration and low yields of existing protocols for in vitro differentiation and by the molecular heterogeneity of the populations generated. We report a combination of small molecules that induce up to 50% motor neurons within 3 weeks from human pluripotent stem cells with defined subtype identities that are relevant to neurodegenerative diseases. Despite their accelerated differentiation, motor neurons expressed combinations of HB9, ISL1 and column-specific markers that mirror those observed in vivo in human fetal spinal cord. They also exhibited spontaneous and induced activity, and projected axons towards muscles when grafted into developing chick spinal cord. Strikingly, this novel protocol preferentially generates motor neurons expressing markers of limb-innervating lateral motor column motor neurons (FOXP1+/LHX3-). Access to high-yield cultures of human limb-innervating motor neuron subtypes will facilitate in-depth study of motor neuron subtype-specific properties, disease modeling, and development of large-scale cell-based screening assays. We analyze 3 samples including 2 positive samples and 1 negative sample. Descriptions are as follow: a) Positive Sample 1: SHH-derived, day 21 GFP-high FACS purified motor neurons.b) Positive Sample 2: S+P-derived, day 21 GFP-high FACS purified motor neurons. c) Negative: S+P condition, day 21 no GFP FACS purified motor neurons
Project description:The goal of this study was to analyze global gene expression in specific populations of nociceptor sensory neurons, the neurons that detect damaging/noxious stimuli. The dorsal root ganglia (DRG), trigeminal ganglia, and nodose ganglia are anatomically distinct peripheral sensory ganglia that contain nociceptors which innervate skin, gut, lungs, and other distinct organ tissues. We used flow cytometry to purify nociceptors from these ganglia and profiled their global gene expression signatures to compare gene expression between these different anatomically distinct nociceptors. Nav1.8-Cre were bred with Rosa26-TdTomato to generate Nav1.8-Cre/R26-TdTomato reporter progeny, where all peripheral nociceptor neurons are genetically marked with red fluroescence due to specific expression of the TTX- resistant sodium channel Nav1.8. Lumbar region dorsal root ganglia (DRG), trigeminal ganglia, and nodose ganglia were dissected from mice (3 mice were pooled/sample). Highly red fluorescent neurons were Facs purified, RNA extracted, and processed for microarray analysis.