Factor Ba neoepitope, Human, mAb D22/3

Monoclonal antibody D22/3 actively targets human complement factor Ba (fBa), playing a pivotal role in the innate immune defense against pathogens. It engages factor Ba at the heart of the alternative pathway (AP) of complement activation, emerging from complement factor B (fB) cleavage by factor D in the presence of Mg2+. This cleavage generates Ba and Bb, positioning Ba as a key attractor of neutrophils and macrophages and a modulator of B cell function. Significantly, high Ba levels in chronic renal disease could signal a compromised immune response.

The D22/3 antibody distinctly recognizes the 234 amino acid glycoprotein Ba, formulated against a synthetic peptide from Ba’s carboxy terminus. It’s important to recognize that the epitope might become exposed in intact factor B under denaturing conditions, such as in SDS-PAGE or western blotting. However, in the fluid phase, D22/3’s precise specificity to Ba stands out, making it a crucial resource for complement research and a potential tool in understanding immune and renal disease mechanisms.