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

CD79b / Tubulin represents a dual-target system utilized by antibody-drug conjugates (ADCs) like polatuzumab vedotin for the treatment of B-cell malignancies [1, 3]. CD79b is a transmembrane protein and a critical component of the B-cell receptor (BCR) complex, expressed almost exclusively on the surface of mature B cells and most B-cell lymphomas [6, 8]. Tubulin is a structural protein that polymerizes into microtubules, which are essential for mitotic spindle formation and intracellular transport [12, 18]. In this therapeutic approach, a monoclonal antibody specifically binds to CD79b, triggering receptor-mediated endocytosis and internalization of the ADC [2, 5]. Once inside the lysosome, the cytotoxic payload (typically monomethyl auristatin E, or MMAE) is released and binds to tubulin, inhibiting its polymerization [4, 11]. This disruption of the microtubule network leads to G2/M phase cell cycle arrest and subsequent apoptosis of the malignant B cell [5, 16]. This targeted delivery mechanism allows for high concentrations of the cytotoxic agent within tumor cells while minimizing systemic exposure and damage to healthy tissues [5, 10]. CD79b is considered an ideal target due to its high expression in B-cell cancers and its rapid internalization upon antibody binding [3, 10].

Other names

CD79BB-cell-specific glycoprotein B29IGBIg-betaTubulinMicrotubule

Antibody-drug conjugate (ADC) targeting CD79b to deliver a microtubule-disrupting payload that binds to tubulin.