B-cell antigen receptor complex-associated protein subunit beta (CD79b) (CD79b)

B-cell antigen receptor complex-associated protein subunit beta (CD79b) is a critical transmembrane protein that, together with CD79a, forms the signaling component of the B-cell receptor (BCR) complex (UniProt). It is essential for B-cell development and activation, as its cytoplasmic immunoreceptor tyrosine-based activation motif (ITAM) initiates intracellular signaling cascades upon antigen binding (PubMed). CD79b is highly expressed on the surface of most B-cell malignancies, including diffuse large B-cell lymphoma (DLBCL) and mantle cell lymphoma, but is notably absent on plasma cells, making it a specific target for immunotherapy (GeneCards). Mutations in the CD79B gene are frequently observed in the activated B-cell (ABC) subtype of DLBCL, where they contribute to chronic, oncogenic BCR signaling (PubMed). The most prominent therapeutic targeting CD79b is polatuzumab vedotin, an antibody-drug conjugate (ADC) that utilizes the receptor's rapid internalization to deliver the microtubule inhibitor monomethyl auristatin E (MMAE) directly into malignant cells (NIH). Other therapeutic approaches under investigation include bispecific antibodies and CAR-T cell therapies designed to exploit CD79b's restricted expression profile (PubMed).

Other names

CD79BB29IGBIg-betaImmunoglobulin-associated betaB-cell-specific glycoprotein B29AGM6

Antibody-drug conjugate (ADC) targeting with cytotoxic payload delivery, B-cell receptor signaling inhibition, and B-cell depletion.