Opsonization / Opsonin

The ability of a phagocyte to bind to a microorganism is enhanced if the microorganism has antibodies bound to it. Antibodies act as bridges to attach the microbe to the antibody receptor FC on the phagocytic cell. If the activated complement protein C3b is bound to the microbe, the degree of binding is further increased by the C3b receptor. If both antibody and C3b opsonize, binding is maximal
Willey et al. 2023 McGraw Hill, USA, ISBN 978-1-265-12303-1

Opsonization is coating of a pathogen by antibodies and/or complement proteins

see also:
Phagocytes