Macrophage interactions with antibodies and soluble immune complexes.

In vitro studies aimed at characterising (1) the binding of monomeric immunoglobulins from a variety of animal species to homologous mononuclear phagocytes, (2) the enhancement in phagocyte binding when antibodies are reacted with soluble antigens to form complexes of defined size, (3) the kinetics of complex ingestion and catabolism by macrophages and the biochemical mechanisms involved, (4) the role of complement in soluble complex catabolism and (5) the stimulatory effects of soluble complexes on phagocyte activity are reviewed. Insights gained from these studies into the in vivo clearance of soluble complexes and into the part played by circulating immune complexes in disease are discussed.