Hemagglutinin-specific B-cell receptor (HA-BCR)

The B-cell receptor (BCR) on HA-specific B lymphocytes is a membrane-bound immunoglobulin molecule that specifically recognizes the hemagglutinin (HA) protein of the influenza virus. HA is the primary surface glycoprotein of influenza, responsible for viral entry into host cells by binding to sialic acid receptors (Krammer, F. Nature 2019). When the BCR on these specific B cells binds to HA, it initiates intracellular signaling cascades via the CD79a/b heterodimer that lead to B cell activation, clonal expansion, and differentiation into antibody-secreting plasma cells or memory B cells (Victora & Nussenzweig, Annu Rev Immunol 2022). This process is the fundamental basis for the efficacy of influenza vaccines, which aim to elicit a robust population of HA-specific B cells and high-affinity neutralizing antibodies (CDC, 2023). Therapeutic strategies often focus on targeting the conserved stem region of the HA protein to induce broadly neutralizing antibodies (bnAbs) through these BCRs, providing protection against multiple influenza strains (NIH, 2021). Monitoring the frequency and affinity of HA-specific BCRs serves as a critical metric for evaluating vaccine immunogenicity and the longevity of the immune response.

Other names

B-cell receptor on HA-specific B lymphocytesInfluenza hemagglutinin-binding B-cell receptorHA-reactive B-cell receptorHemagglutinin-binding BCR

Antigen-mediated cross-linking of the B-cell receptor by the influenza hemagglutinin protein triggers intracellular signaling via the CD79a/b heterodimer, leading to B cell proliferation and differentiation into plasma cells that secrete neutralizing antibodies (Victora & Nussenzweig, Annu Rev Immunol 2022).