B-cell receptor recognizing Influenza A virus H9 hemagglutinin (BCR (H9 HA))

The B-cell receptor (BCR) recognizing H9 hemagglutinin epitopes is a membrane-bound immunoglobulin complex on B lymphocytes that specifically identifies the hemagglutinin (HA) surface glycoprotein of H9-subtype influenza viruses (Source: PubMed PMID 31434738). The BCR consists of an antigen-binding subunit and the CD79A/B signaling heterodimer, which together mediate the initial stage of the humoral immune response (Source: UniProt P11912, P40259). Upon binding to H9 HA epitopes, the BCR triggers intracellular signaling that leads to B-cell proliferation and the production of neutralizing antibodies (Source: PubMed PMID 28834717). This receptor is a critical target in the development of vaccines against H9N2 avian influenza, a virus with significant pandemic potential due to its widespread presence in poultry and occasional transmission to humans (Source: WHO Influenza Fact Sheet). Therapeutic strategies focus on eliciting BCRs that recognize conserved epitopes, such as the HA stem, to provide broad protection against diverse H9 strains (Source: PubMed PMID 30209165). Challenges in targeting this receptor include the rapid antigenic drift of the influenza virus, which can render previously effective BCR recognition obsolete (Source: CDC Influenza Viruses).

Other names

H9-specific B-cell receptorSurface immunoglobulin recognizing H9 HAAnti-H9 BCRB-cell receptor complex

Antigen-mediated BCR cross-linking and activation of downstream signaling cascades (e.g., Syk, PLC-gamma2) leading to B-cell differentiation into antibody-secreting plasma cells and memory B cells.