B-cell receptor (BCR) and Autoantibody (BCR)

The B-cell receptor (BCR) is a transmembrane protein complex on B-lymphocytes composed of an antigen-binding immunoglobulin and signaling subunits CD79A and CD79B (UniProt: P11912, P40259). It plays a central role in the immune response by recognizing antigens and triggering signaling cascades, such as the Bruton's tyrosine kinase (BTK) pathway, which lead to B-cell activation and antibody production (NCBI: NBK538515). In autoimmune diseases, BCRs on autoreactive B-cells recognize self-antigens, resulting in the secretion of pathogenic autoantibodies that cause systemic inflammation and tissue damage (StatPearls: Autoimmunity). These autoantibodies are key drivers of conditions like systemic lupus erythematosus (SLE) and rheumatoid arthritis. Therapeutic interventions target this axis through B-cell depletion (e.g., Rituximab targeting CD20), inhibition of BCR signaling (e.g., Ibrutinib targeting BTK), or by accelerating the clearance of autoantibodies via FcRn inhibition (e.g., Efgartigimod) (DrugBank: DB00073, DB11903). Managing these targets is essential for treating both autoimmune disorders and B-cell malignancies, though it carries risks of significant immunosuppression.

Other names

B-cell antigen receptorSurface immunoglobulinAutoreactive antibodySelf-reactive antibodyBCR complex

Inhibition of Bruton's tyrosine kinase (BTK) signaling; Depletion of B-lymphocytes via CD20 targeting; Inhibition of neonatal Fc receptor (FcRn) to increase autoantibody clearance; Neutralization of B-cell activating factor (BAFF) to reduce B-cell survival.