Integrin ανβ1 is an adenovirus coreceptor

The human embryonic kidney (HEK293) cell line, commonly used for recombinant adenovirus (Ad) propagation, does not express the Ad coreceptor alphav beta3 or alphav beta5 integrins, yet these cells are efficiently infected by Ad vectors. Here we demonstrate that Ad binds to HEK293 cells via the fiber receptor CAR and is subsequently internalized via interaction with integrin (alphav beta1, Function-blocking antibodies directed against alphav or beta1, but not beta3, beta5, or alpha5, integrin subunits block Ad infection and viral endocytosis, Therefore, alphav beta1 serves as a coreceptor for Ad infection, and the lack of beta3 and/or beta5 but the relatively high expression of alphav beta1 integrins on certain tumor cell types may explain why these cells are readily transduced by Ad vectors.