IDENTIFICATION OF A MAJOR CORECEPTOR FOR PRIMARY ISOLATES OF HIV-1

Entry of HIV-1 into target cells requires cell-surface CD4 and additio nal host cell cofactors. A cofactor required for infection with virus adapted for growth in transformed T-cell lines was recently identified and named fusin. However, fusin does not promote entry of macrophage- tropic viruses, which are believed to be the key pathogenic strains in vivo. The principal cofactor for entry mediated by the envelope glyco proteins of primary macrophage-tropic strains of HIV-1 is CC-CKR-5, a receptor for the beta-chemokines RANTES, MIP-1 alpha and MIP-1 beta.