Single-cell census of the colonic epithelium reveals goblet cell drivers of barrier breakdown in inflammatory bowel disease

Colonic epithelial cells facilitate host-microbe interactions to control mucosal immunity, and they also coordinate recycling and forming the mucus barrier. Epithelial barrier breakdown underpins inflammatory bowel disease (IBD). However, we do not know the specific contributions of each epithelial cell subtype to this process. Here, we profiled single colonic epithelial cells in health and IBD. Our results identified previously unknown subtypes and crypt gradients of progenitors, colonocytes and goblet cells. We also revealed a novel specialized metal ion storage and chloride secretory cell. In IBD, we discovered a unique cluster of disease associated goblet cells that remodels the barrier. We found downregulated WFDC2, a novel goblet cell expressing anti-protease that inhibited bacterial growth. Our in vivo studies demonstrated WFDC2 preserved tight junction integrity and prevented commensal invasion and mucosal inflammation. We delineate markers and transcriptional states, identify a new colonic epithelial cell and uncover fundamental principles of epithelial plasticity and barrier breakdown in IBD. Thus, our study reveals new therapeutic targets and disease-related mechanisms in IBD