Junctional Gating: The Achilles' Heel of Epithelial Cells in Pathogen Infection

SummaryMucosal epithelial cells are a major barrier restricting pathogen entry and, paradoxically, an important entry port for respiratory and enteric viruses. Elegant studies in this issue of Cell Host & Microbe describe how coxsackievirus B3 (related to human poliovirus) infects polarized epithelial cells by engaging two transmembrane proteins of the tight junctions, occludin and CAR. A distinctive endocytic mechanism opens the junctions and gates infectious virus entry.