Eosinophilic esophagitis (EoE) arises in the setting of type 2 cytokine-driven inflammation, is characterized by the infiltration of eosinophils in the esophageal mucosa, and is associated with dysphagia and fibrostenotic complications. Disease development and progression involve complex interactions between epithelial cells, stromal cells and immune cells. Indeed, increased epithelial permeability is consistently found in EoE, potentially leading to increased antigen exposure and inflammation. Persistent inflammation can in turn lead to fibroblast activation and fibrosis, which, together with the mediators produced by eosinophils and mast cells, leads to dysmotility. To decipher the interactions between these cell types across distinct disease states, we obtained biopsies from 7 healthy controls and 15 EoE subjects, including both active disease and clinical remission, to perform single cell RNA-sequencing (scRNA-seq).Each biopsy sample was enzymatically digested within 3 hours of collection with collagenase/dispase to generate a single cell suspension. Suspensions were then loaded on a 10x Chromium controller, and libraries were generated with the 3' Chemistry pipeline (v2 or v3) before sequencing on an Illumina sequencer. The resulting sequence data was demultiplexed and analyzed with the CellRanger pipeline to generate raw fastq files and processed gene-count matrices for each sample. Altogether, our study generated transcriptomic profiles from 421,312 individual cells after quality control and filtering.Our analyses reveal 60 cell subsets and functional alterations in cell states, compositions, and interactions that highlight previously unknown features of EoE. Active disease displayed enrichment of <a href="https://www.ncbi.nlm.nih.gov/gene/246">ALOX15</a>+ macrophages, novel <a href="https://www.ncbi.nlm.nih.gov/gene/63976">PRDM16</a>+ dendritic cells expressing the EoE risk gene <a href="https://www.ncbi.nlm.nih.gov/gene/57194">ATP10A</a>, and cycling mast cells, with concomitant reduction of TH17 cells. Receptor–ligand expression uncovered eosinophil recruitment programs, increased fibroblast interactions in disease, and IL-9+IL-4+IL-13+TH2 and endothelial cells as potential mast cell interactors. Resolution of inflammation-associated signatures included mast and CD4+ Tissue-resident memory T (TRM) cell contraction and cell type-specific downregulation of eosinophil chemoattractant, growth, and survival factors.

Adult Eosinophilic Esophagitis Registry Atlas