B-cell receptor on Hepatitis B virus-specific B cells (HBV-specific BCR)

The B-cell receptor (BCR) on Hepatitis B virus (HBV)-specific B cells is a specialized transmembrane protein complex that mediates the recognition of viral antigens, primarily the Hepatitis B surface antigen (HBsAg) and core antigen (HBcAg). In patients with chronic hepatitis B (CHB), these BCR-bearing B cells often exhibit a dysfunctional or exhausted phenotype, characterized by impaired proliferation and a failure to differentiate into antibody-secreting plasma cells (Burton et al., 2018, J Exp Med). This dysfunction contributes to the persistence of the virus and the lack of protective anti-HBs antibodies. Therapeutic strategies target these receptors using immunotherapeutic vaccines, such as BRII-179, to provide optimized antigenic stimuli that can bypass immune tolerance and re-activate the B-cell response (Brii Biosciences, 2023). Engagement of the HBV-specific BCR triggers signaling cascades through the CD79a and CD79b subunits, leading to the restoration of humoral immunity and the potential for a functional cure, defined by sustained HBsAg loss (Salimzadeh et al., 2018, J Clin Invest). Monitoring the frequency and activation state of these specific B cells is a critical component of evaluating the efficacy of novel HBV immunotherapies.

Other names

HBsAg-specific B-cell receptorHBcAg-specific B-cell receptorHepatitis B virus-specific B-cell receptorHBV-specific BCR complex

Binding of specific HBV antigens or vaccine-derived epitopes to the BCR triggers intracellular signaling pathways (via CD79a/b) that promote B-cell maturation, proliferation, and differentiation into plasma cells capable of secreting neutralizing anti-HBs antibodies.