HIV-1 envelope glycoprotein CD4 binding site (None established; sometimes referred to as HIV-1 Env CD4bs or gp120 CD4bs in literature, but no universal abbreviation.)

The HIV-1 envelope glycoprotein CD4 binding site is a highly conserved surface region on the gp120 subunit of the HIV-1 Env trimer, mediating the primary attachment of the virus to the CD4 receptor on host T cells[1][3][8][6]. This interaction is essential for viral entry, with subsequent conformational changes in gp120 and gp41 enabling membrane fusion and infection[2][1][7]. The CD4 binding site is a major target for neutralizing antibodies, especially broadly neutralizing antibodies, and for antiviral drug development. Its structural complexity, conformational flexibility, and partial masking by glycans and variable loops facilitate immune evasion and present significant challenges for vaccine and therapeutic design[4][5][8]. The site is the subject of intense research for vaccines and monoclonal antibody interventions due to its functional indispensability and relative conservation across HIV-1 strains[5][6].

Other names

HIV-1 Env CD4 binding sitegp120 CD4 binding siteCD4bsHIV-1 gp120 CD4bs

Inhibition of gp120-CD4 interaction to prevent viral entry (antibodies/mimetics compete for the binding site); Induction of conformational change in Env, reducing or blocking the ability of HIV-1 to infect host cells; Antibody-mediated neutralization (broadly neutralizing antibodies bind and block receptor interaction)