In the gastrointestinal tract, intraepithelial lymphocytes are tasked with protecting the epithelium against pathogens and participating in wound repair and correct mucosal barrier functioning. In a study published in the Sept. 15, 2023, issue of Science, researchers at King’s College London and collaborators have identified a specific subset of gamma-delta (γδ) T cells in the human gut, Vγ4 cells, which seems to protect against inflammatory bowel disease (IBD) progression.