Envelope glycoprotein GP120

It was discovered by Professors Tun-Hou Lee and Myron "Max" Essex of the Harvard School of Public Health in 1984.

[9] The diversity of env has been shown to increase by 1-2% per year in HIV-1 group M and the variable units are notable for rapid changes in amino acid sequence length.

[10] Further studies have shown that variability in potential N-linked glycosylation sites (PNGSs) also result in increased viral fitness.

Sequence data shows that initial viral variants in an immunologically naïve host have few glycosylation sites and shorter exposed variable loops.

Efforts to develop HIV vaccines targeting gp120, however, have been hampered by the chemical and structural properties of gp120, which make it difficult for antibodies to bind to it.

[16] [17] NIH research published in Science reports the isolation of 3 antibodies that neutralize 90% of HIV-1 strains at the CD4bs region of gp120, potentially offering a therapeutic and vaccine strategy.

[1] However, most antibodies that bind the CDbs region of gp120 do not neutralize HIV,[18] and rare ones that do such as IgG1-b12 have unusual properties such as asymmetry of the Fab arms[19] or in their positioning.

No agent targeting gp120's main first cellular interaction partner, CD4, is currently licensed since interfering with such a central molecule of the immune system can cause toxic side effects, such as the anti-CD4 monoclonal antibody OKT4.

[22] The HIV viral protein gp120 induces apoptosis of neuronal cells by inhibiting levels of furin and tissue plasminogen activator, enzymes responsible for converting pBDNF to mBDNF.