Human immunodeficiency virus type 1 envelope glycoprotein 120 (gp120)

The HIV-1 envelope glycoprotein 120 (gp120) is a heavily glycosylated protein that forms the outer layer of the HIV-1 envelope spikes, playing a critical role in the early stages of viral infection. It functions by binding to the CD4 receptor on the surface of host immune cells, such as T-helper cells and macrophages, which triggers a conformational change allowing subsequent binding to co-receptors like CCR5 or CXCR4. This interaction is the essential first step for viral entry and subsequent replication within the host. Because of its exposed position on the virion surface, gp120 is a primary target for the host immune response and a major focus for the development of entry inhibitors and vaccines. However, its high mutation rate and dense glycan shield present significant challenges for therapeutic intervention, as the virus can rapidly evolve to escape neutralization. Current drugs like fostemsavir specifically target gp120 to prevent viral attachment, offering a vital option for patients with multidrug-resistant HIV-1 infections.

Other names

Envelope surface glycoprotein gp120Surface proteinSUHIV-1 gp120Env

Gp120-directed attachment inhibitors bind directly to the gp120 subunit of the viral envelope, preventing the initial interaction between the virus and the host CD4 receptor, thereby blocking viral entry into the cell.