Human immunodeficiency virus 1 envelope glycoprotein gp120 V3-base glycan epitope (HIV-1 gp120 V3 glycan epitope)

The HIV-1 Env gp120 V3 glycan epitope is a critical antigenic region located on the surface of the HIV-1 envelope glycoprotein (Env). It is characterized by a cluster of high-mannose N-linked glycans, most notably the glycan at position N332, which serves as a focal point for recognition by several classes of broadly neutralizing antibodies (bNAbs) (Kong et al., 2013, Nature Structural & Molecular Biology). This epitope is part of the 'glycan shield' that the virus uses to hide its protein surface from the host immune system, yet it remains a vulnerable 'supersite' because the glycans themselves form a stable target for potent antibodies (Sok et al., 2016, Science Immunology). In the viral lifecycle, the gp120 subunit facilitates the initial attachment of HIV-1 to CD4+ T cells. Therapeutic targeting of the V3 glycan epitope is a major focus of HIV-1 cure and prevention research, utilizing monoclonal antibodies such as PGT121 and 10-1074 in clinical trials to suppress viremia and provide passive immunity (Caskey et al., 2017, Nature Medicine). Because this site is relatively conserved across many HIV-1 clades, it is also a primary candidate for immunogen design in vaccine development aimed at eliciting broad-spectrum protection (Sanders & Moore, 2017, Nature Reviews Immunology).

Other names

N332-glycan supersiteV3-glycan patchgp120 V3 loop glycan clusterMan9GlcNAc2 glycan epitopeV3-base glycan epitope

Neutralization of viral entry by binding to the gp120 V3 loop base and associated high-mannose glycans, thereby blocking the functional envelope trimer from interacting with host cell receptors.