Utilization of Immunoglobulin G Fc Receptors by Human Immunodeficiency Virus Type 1: a Specific Role for Antibodies against the Membrane-Proximal External Region of gp41

Broad Neutralization of Human Immunodeficiency Virus Type 1 Mediated by Plasma Antibodies against the gp41 Membrane Proximal External Region

“…Consistent with this, MAbs 2F5, 4E10, and Z13e1, as well as plasma BB34, neutralize JR-FL after CD4 and CCR5 attachment, when this occluded epitope is exposed (2,3). Furthermore, BB34 neutralization was potentiated by coexpression of Fc␥RI on JC53bl-13 cells, also a feature of 2F5 and 4E10, possibly by providing a kinetic advantage through prepositioning of these antibodies close to the MPER (22). However, it remains unclear how these antibodies are induced in the context of natural infection despite the exposure constraints of this epitope.…”

Neutralizing IgG at the Portal of Infection Mediates Protection against Vaginal Simian/Human Immunodeficiency Virus Challenge

“…2F5 IgG was most potent against infection of MDM, although this was reduced in the presence of serum, as previously described (56). Comparison of 2F5 IgG and Fab highlighted the important influence of Fc-mediated effects in the different in vitro models.…”

FCGR2C polymorphisms associate with HIV-1 vaccine protection in RV144 trial

“…FCGR2C shares the extracellular sequence of FCGR2B but signals through the ITAM like FCGR2A. Interestingly, FCGR2C has been reported capable of mediating ADCC (30)(31)(32) and may play a role in anti-HIV-1 Ab-neutralizing activity, similar to FCGR2B (33). In this study, we identified a tag SNP in FCGR2C (FCGR2C 126C>T, rs114945036) that significantly modified VE to prevent infection with CRF01_AE circulating strains in Thailand that expressed lysine at position 169 (169K).…”