B-cell receptor specific for HIV-1 Nef epitopes (BCR-Nef)

The B-cell receptor (BCR) specific for HIV-1 Nef epitopes is a membrane-bound immunoglobulin on B lymphocytes that recognizes the HIV-1 Negative Regulatory Factor (Nef). Nef is a 27-35 kDa myristoylated protein essential for high-titer viral replication and pathogenesis (Geyer et al., 2001, PubMed: 11591354). It functions by downregulating CD4 and MHC-I molecules, thereby shielding infected cells from T-cell recognition. Although primarily intracellular, Nef is secreted via exosomes and can be found on the plasma membrane, allowing it to be targeted by BCRs (Campbell et al., 2008, PubMed: 18499632). Activation of these specific BCRs leads to the production of anti-Nef antibodies, which are often found in HIV-infected individuals and may correlate with slower disease progression (Luo et al., 2012, PubMed: 22496668). Therapeutic strategies involve using Nef-based vaccines to stimulate these BCRs or developing chimeric antigen receptors (CARs) based on Nef-specific antibody sequences. Challenges include the high genetic variability of the Nef gene and the limited accessibility of the protein compared to the viral envelope.

Other names

Nef-specific B-cell receptorAnti-HIV-1 Nef BCRHIV-1 Nef-specific immunoglobulin

Binding of the B-cell receptor to HIV-1 Nef epitopes triggers B-cell activation and differentiation into plasma cells, which secrete antibodies that neutralize extracellular Nef and mediate the clearance of infected cells via Fc-mediated effector functions (Luo et al., 2012, PubMed: 22496668).