Entry of viruses through the epithelial barrier: pathogenic trickery

Mucosal surfaces — such as the lining of the gut or the reproductive tract — are the main point of entry for viruses into the body. As such, almost all viruses interact with epithelial cells, and make use of the normal epithelial signalling and trafficking pathways of the host cell. In addition to protein receptors, carbohydrate chains of proteoglycans and epithelial-membrane glycosphingolipids have emerged as a new class of receptors for viral attachment to the host cell.