Regulation of intestinal immunity and tissue repair by enteric glia (Single-cell expression analysis of small intestinal glia cells in naïve and H. poly-infected mice.)

Tissue maintenance and repair depend on the integrated activity of multiple cell types. Whereas the contributions of epithelial, immune and stromal cells in intestinal tissue integrity are well understood, the role of intrinsic neuroglia networks remains largely unknown. Here, we uncover pivotal roles of enteric glial cells (EGCs) in intestinal homeostasis, immunity and tissue repair. We demonstrate that infection of mice with Heligmosomoides polygyrus (H. poly) leads to enteric gliosis and upregulation of the interferon gamma (IFN-γ) gene signature. Single-cell transcriptomics of tunica muscularis (TM) showed that glia-specific abrogation of IFN-γ signaling leads to tissue-wide activation of pro-inflammatory transcriptional programs. In addition, disruption of the IFN-γ-EGC signaling axis enhanced the inflammatory and granulomatous response of TM to helminths. Mechanistically, we show that upregulation of Cxcl10 is an early immediate response of EGCs to IFN-γ signaling and provide evidence that this chemokine and the downstream amplification of IFN-γ signaling in the TM are required for a measured inflammatory response to helminths and resolution of granulomatous pathology. Our study demonstrates that IFN-γ signaling in enteric glia is central to intestinal homeostasis and reveals critical roles of the IFN-γ-EGC-Cxcl10 axis in immune response and tissue repair following infectious challenge. To characterize the response of enteric glia to helminth infection at single cell resolution, we next performed scRNAseq (C1 Fluidigm platform) of tdT+ cells from the TM of naïve and H. poly-infected mice. To investigate how EGCs respond to pathogen invasion, tamoxifen-treated Sox10CreERT2;Rosa26tdTomato mice, which express the fluorescent reporter tdTomato (tdT) specifically in the intrinsic glia cell network of the gut, were infected with H. poly. At 7 days post, we isolated enteric glia cells (EGCs) from five biological samples (2x naïve and 3x H. poly infected animals (7 dpi)) from both male and female Sox10CreERT2;Rosa26tdTomato adult mice at 24 hours after tamoxifen induction.