Anti-Human CD79b (Polatuzumab) [Clone RG7596] (C1090-GRP)

CD79 is a covalent heterodimer, composed of CD79a and CD79b, that acts as the signaling component of the B cell receptor (BCR) 1 and is also a tumor associated antigen 2. CD79 together with surface Ig forms the BCR complex, and cross-linking of BCR triggers downstream signaling that can lead either to apoptosis or, when rescue signals from T cells are present, cell activation 1. Cross-linked BCR is internalized and targeted by a lysosome-like compartment, the major histocompatibility complex class II positive compartment, making CD79b a target antigen for antibody drug conjugates (ADC) against cancerous B cells 1. Polatuzumab is an ADC composed of an antibody directed against CD79b on B cells covalently bound via a cleavable linker to Microtubule-disrupting anti-mitotic agent monomethyl auristatin (MMAE) 2, an apoptosis stimulant that inhibits mitosis, tubulin, and tubulin polymerization 2. This research grade biosimilar has the same specificity as the original therapeutic antibody but lacks the conjugated MMAE drug. Polatuzumab was generated by immunizing mice with the extracellular domain of CD79b 1, 4. Recombinant technology was then used to humanize the anti-CD79b antibody and sequence optimize it. Polatuzumab has been approved for the treatment of some adults with relapsed/refractory diffuse large B cell lymphoma (DLBCL) and various clinical trials are in progress 1.