B-cell receptor specific for influenza A(H1N1)pdm09 hemagglutinin (BCR-HA (Apdm09))

The B-cell receptor (BCR) specific for the influenza A(H1N1)pdm09 hemagglutinin is a membrane-bound immunoglobulin complex on B lymphocytes that recognizes the hemagglutinin (HA) protein of the 2009 pandemic H1N1 virus (Xu et al., Science, 2010). This receptor is essential for the adaptive immune response, as its engagement by viral HA triggers signaling through the CD79a/CD79b heterodimer, leading to B-cell activation and the production of neutralizing antibodies (Reth & Wienands, Nature Reviews Immunology, 2010). In clinical practice, this BCR is the primary target of influenza vaccines, which aim to stimulate the expansion of B-cell clones capable of producing high-affinity antibodies against the HA head or stalk domains (Wrammert et al., Journal of Experimental Medicine, 2011). Research into these specific BCRs has facilitated the development of broadly neutralizing antibodies (bnAbs) that target conserved epitopes, offering a strategy for universal influenza protection (Corti et al., Nature, 2015). Understanding the repertoire and affinity maturation of these receptors is crucial for monitoring vaccine efficacy and predicting the impact of viral antigenic drift (Pappas et al., Cell, 2016).

Other names

H1N1pdm09 HA-specific B-cell receptorAnti-influenza A(H1N1)pdm09 hemagglutinin BCRA/California/04/2009 (H1N1) hemagglutinin-specific BCRAnti-HA BCR (Apdm09)

The hemagglutinin antigen in vaccines binds to the specific B-cell receptor, inducing receptor clustering and phosphorylation of immunoreceptor tyrosine-based activation motifs (ITAMs) on the CD79a/CD79b subunits. This triggers an intracellular signaling cascade involving Syk and PLC-gamma-2 that activates transcription factors, leading to B-cell proliferation, germinal center formation, and differentiation into antibody-secreting plasma cells.