Tumor cells opsonized by therapeutic antibodies

Tumor cells opsonized by therapeutic antibodies represent a biological complex where malignant cells are coated with monoclonal antibodies (mAbs), marking them for recognition and destruction by the immune system. This opsonization process is a critical step in the mechanism of action for many cancer immunotherapies, as it facilitates Antibody-Dependent Cellular Cytotoxicity (ADCC) and Antibody-Dependent Cellular Phagocytosis (ADCP) (Frontiers in Immunology, 2024). Effector cells, such as Natural Killer (NK) cells, macrophages, and neutrophils, recognize the Fc portion of the bound antibodies via various Fc gamma receptors (FcγRs), such as CD16, CD32, and CD64 (NIH, 2023). Additionally, the interaction between CD47 on the tumor cell and SIRP alpha on the macrophage acts as a "don't eat me" signal that can inhibit the phagocytosis of these opsonized cells. Therapeutic strategies targeting this complex include the use of SIRP alpha-CD47 inhibitors to unleash the phagocytic potential of macrophages against opsonized tumor cells, as well as Fc-engineered antibodies designed to enhance binding affinity to activating Fc receptors (Nature Reviews Drug Discovery, 2022).

Other names

Opsonized tumor cellsAntibody-coated tumor cellsmAb-opsonized tumor cellsAntibody-dependent cellular phagocytosis targetAntibody-dependent cellular cytotoxicity target

Enhancement of Antibody-Dependent Cellular Phagocytosis (ADCP) and Antibody-Dependent Cellular Cytotoxicity (ADCC) by blocking inhibitory signals (e.g., CD47-SIRP alpha axis) or improving Fc receptor engagement on effector cells.