The first line of host defence against both encroaching commensal bacteria and invading enteric pathogens is the intestinal mucosal barrier, which is composed of epithelial cells and a host-secreted mucous layer. In this Review, Martens and colleagues discuss the complex interactions of commensal and pathogenic microorganisms with the intestinal mucosal barrier.
- Eric C. Martens
- Mareike Neumann
- Mahesh S. Desai