•Rethinking colitis: MrgprD puts macrophages in the driver's seat†
•MrgprD-mediated macrophage polarization drives chemically induced colitis in mice
•Engineered E. coli Nissle 1917 alleviates colitis-associated depression via gut-brain axis restoration
•Akkermansia muciniphila WW001 protects against DSS-induced colitis by restoring intestinal barrier integrity and modulating inflammatory responses
•PSC-DM: A Validated Clinical Diagnostic Model for Distinguishing Primary From Secondary Sclerosing Cholangitis