Enterocloster clostridioformis induces host intestinal epithelial responses that protect against Salmonella infection

Promoting resistance to enteric pathogen infection is a core function of the gut microbiota. However, many of the host-commensal interactions that likely mediate this protection remain uncharacterised. By screening gnotobiotic mice monocolonised with a range of mouse-derived commensal bacteria we have identified Enterocloster clostridioformis as a protective species against Salmonella Typhimurium infection. Unlike the colonisation resistance induced by some commensal bacteria, E. clostridioformis selectively induces a previously uncharacterised microbe adaptation response at the level of the caecal intestinal epithelium and the underlying mucosal immune system to mediate host-dependent resistance to infection. Triggering this pathway may therefore constitute a novel strategy to enhance protective responses against enteric infections.