Epithelial–immune crosstalk in health and disease

Far from inert structures, our body's epithelial boundaries engage in a dynamic crosstalk with immune cells that is vital for immune surveillance and barrier function. Using the skin and gut epithelium, two structurally distinct but critical environmental interfaces, here we review the context-dependent interactions between myriad immune cells and epithelial subsets. We discuss immune communique reserved for epithelial progenitors and the enduring consequences for tissue fitness. Then, we delve into the cellular and molecular exchanges between differentiated epithelial subsets and adjacent immune cells. Therapeutically targeting stage-specific immune-epithelial interaction could boost regeneration and mitigate inflammatory pathologies.