(Left) The CD40 agonistic antibody, APX0005M, has mutations (indicated by stars) in the heavy chains that increase its specific binding to FcγRIIB and minimize its binding to FcγRIIA. The pink regions are the part of the antibody that recognizes CD40. (Middle) The unaltered CD40 antibody interacts with cell with both types of Fc receptors (yellow and green), such as macrophages, and CD40 (orange) on antigen-presenting dendritic cells to stimulate a weak anti-tumor response. (Right) The mutated antibody interacts with cells that have abundant FcγRIIB (yellow), such as B cells, which clusters the antibody and CD40 on the dendritic cells, and stimulates a strong anti-tumor response. [Credit: Heather McDonald]
Read more at
N. R. Gough, Optimizing anti-tumor therapies with engineered antibodies. BioSerendipity (18 September 2018) https://www.bioserendipity.com/optimizing-anti-tumor-therapies-with-engineered-antibodies/