Cellular proteases involved in the pathogenicity of human immunodeficiency and influenza viruses.

Current understanding of the interactions between animal viruses and host cellular factors, such as virus receptors in the membrane and intracellular factors for viral replication, which determine the pathogenicity and infectious tropism of viruses, has considerably progressed. Current knowledge of membrane receptors for animal viruses are summarized in Table I. Viruses recognize and specifically bind to adhesion molecules in the membrane as receptors, many of which are members of the immunoglobulin (IgG) superfamily. These include the 70K IgG family of proteins for poliovirus, ICAM-1 for rhinovirus and CD4 for human immunodeficiency virus type-1 (HIV-1). Other virus receptors are receptors for hormones and proteins, such as the EGF receptor for vaccinia virus and s-adrenergic receptor for reovirus, complement receptor for EB virus and sialic acid for influenza and Sendai viruses.