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an antibody that renders bacteria and other cells susceptible to phagocytosis. adj., adj opson´ic.
immune opsonin an antibody that sensitizes a particulate antigen to phagocytosis.
antibodies formed in response to stimulation by a specific antigen, either as a result of an attack of a disease or as a result of injections with a suitably prepared suspension of the specific microorganism.
Opsonin formed after stimulation by a specific antigen.
See also: opsonin
a substance such as antibody, complement or properdin that renders bacteria and other cells more susceptible to phagocytosis.
an antibody that, when bound to particulate antigen, enhances in vivo or in vitro phagocytosis; the Fc portion of the antibody binds to an Fc receptor on the surface of the phagocytic cell.