CD40

Class

Anti-CD40 monoclonal antibody

Notes

original target text: CD40 | original target text: CD40 (inhibitor)

CD40 is a receptor found on antigen-presenting immune cells, including B cells, dendritic cells, and macrophages. It is engaged by CD40 ligand (CD40L), a protein displayed on activated T cells, and this interaction is a central costimulatory signal in adaptive immunity. When CD40 is engaged, B cells are prompted to proliferate, switch the type of antibody they produce, and form germinal centers—specialized structures where high-affinity antibody responses are generated; dendritic cells become more effective at activating T cells. In autoimmune and inflammatory diseases, this costimulatory circuit can become chronically overactive, sustaining harmful antibody production and T cell activation against the body's own tissues. Antagonist antibodies directed against CD40, such as the molecule described here, are designed to bind the receptor and physically block its engagement by CD40L, thereby dampening this costimulatory signal without directly killing or depleting the cells that carry it. This approach is being explored across conditions where excessive B cell and T cell cooperation drives disease, including inflammatory bowel disease, lupus, and rejection of transplanted organs. The therapeutic rationale rests on interrupting a proximal, rate-limiting step in adaptive immune activation rather than broadly suppressing immune function.