GSE184423
Single cell RNA sequencing of mesenteric lymph node dendritic cells in segmented filamentous bacteria(SFB)-colonized C57BL/6 mice
Purpose: The goal of this study is to identify gut dendritic cells that induces CD4 Th17 cells that play an critical role in mucosal immunity Methods: C57BL/6 mice were orally gavaged with fecal material derived from SFB-positive donor mice. Five days post oral gavage, mesenteric lymph nodes were harvested and dendritic cells were FACS-sorted. cDNA library from migratory dendritic cells (MHCII-highCD11c+) and resident dendritic cells (MHCII+CD11c-high) were generated using Chromium Single Cell 3' Library v2 Kit (10x Genomics). RNA sequencing was performed using NovaSeq S4 flow cell (Illumina). Data was processed using the Cell Ranger software (10x Genomics) followed by analysis using the R-based package Seurat. Results: Gut colonization with SFB increased the migration of type 2 but not type 1 dendritic cells to the mesenteric lymph nodes. Based on transcriptomic profiles, migratory type 2 dendritic cells consist of 2 major cell clusters (Cd40-Ccl22 and Cd1d1-Tnfrsf4-enriched cells). The Th17 response inducing cytokine IL-6 co-localized with the Cd40-Ccl22-expressing cells. Conclusion: Our study represents the first to carefully characterize the mucosal dendritic cells at steady state and during acute CD4 Th17 response. Transcriptomic profiling enabled the subsetting of dendritic cells based on functional markers (such as cytokines and chemokines) that are otherwise difficult to measure at the protein level. These results provide a focused look at mucosal dendritic cells and their roles in dictating different T cell responses. Overall design: Examination of gut migratory dendritic cells and lymph node resident dendritic cells in naïve and SFB-colonized mice.