Specific binding of T lymphocytes to macrophages. I. Kinetics of binding.
Peritoneal exudate lymphocytes obtained from immune guinea pigs and cultured for 1 week on antigen-pulsed autologous macrophages were tested for their ability to bind to fresh antigen-pulsed autologous macrophages or to macrophages pulsed with an irrelevant antigen. Up to 30% of the lymphocytes bound to macrophages bearing the relevant antigen whereas only 2 to 5% remained nonspecifically bound to macrophages after vigorous washing. Specific binding was observed in cultures as early as 1 hr. Analysis of the kinetics of binding suggests that the observed nonspecific binding is not a step in specific binding. The possibility that weaker antigen-independent association between lymphocytes and macrophages precedes specific binding cannot be excluded. No evidence was obtained that serum antibody adsorbed to the macrophage or T cell plays a role in this cell interaction or that the T cell can bind antigen directly. We suggest that the observed specific binding represents the initial event in stimulation of T lymphocytes by antigen.
D000818:Animals; D000941:Antigens; D001202:Ascitic Fluid / Q000166:cytology / Q000276:immunology; D002462:Cell Membrane / Q000276:immunology; D006168:Guinea Pigs; D007109:Immunity; D007141:Immunoglobulin Fc Fragments; D066298:In Vitro Techniques; D007700:Kinetics; D008198:Lymph Nodes / Q000166:cytology / Q000276:immunology; D008213:Lymphocyte Activation; D008264:Macrophages / Q000276:immunology*; D011947:Receptors, Antigen, B-Cell; D013601:T-Lymphocytes / Q000276:immunology*
D000941:Antigens; D007141:Immunoglobulin Fc Fragments; D011947:Receptors, Antigen, B-Cell