Interaction of coxsackievirus A21 with its cellular receptor, ICAM-1

Coxsackievirus A21 (CAV21), like human rhinoviruses (HRVs), is a causative agent of the common cold. It uses the same cellular receptor, intercellular adhesion molecule 1 (ICAM-1), as does the major group of HRVs; unlike HRVs , however, it is stable at acid pH. The cryoelectron microscopy (cryoEM) im age reconstruction of CAV21 is consistent with the highly homologous crysta l structure of poliovirus I; like other enteroviruses and HRVs, CAV21 has a canyon-like depression around each of the 12 fivefold vertices. A cryoEM r econstruction of CAV21 complexed with ICAM-1 shows all five domains of the extracellular component of ICAM-1. The known atomic structure of the ICAM-1 amino-terminal domains D1 and D2 has been fitted into the cryoEM density o f the complex. The site of ICAM-1 binding within the canyon of CAV21 overla ps the site of receptor recognition utilized by rhinoviruses and poliovirus es. Interactions within this common region may be essential for triggering viral destabilization after attachment to susceptible cells.