Antibody opsonization

Antibody opsonization is a process by which a pathogen is marked for phagocytosis through coating of a target cell with antibodies. Immunoglobulins participate in molecular tagging of pathogens which display antigens recognised by their specific paratope. The binding of antibodies enhances pathogen identification and recruitment of immune effector cells, ultimately accelerating microbial clearance through phagocytic destruction or antibody-dependent cellular cytotoxicity.

1) Antibodies (A) and pathogens (B) circular in the blood. 2) The antibodies bind to pathogens with complementary antigen sequences, engaging in opsonization (2a), neutralisation (2b), and agglutination (2c). 3) A phagocyte (C) approaches the pathogen, and Fc region (D) of the antibody binds to one of the Fc receptors (E) on the phagocyte. 4) Phagocytosis of antibody-marked pathogen