Antigen handling by guinea pig macrophages: further evidence for the sequestration of antigen relevant for activation of primed T lymphocytes.
Guinea pig macrophages can take up sufficient 2,4 dinitrophenyl guinea pig albumin during a brief in vitro exposure at 37 degrees C to trigger proliferation and lymphokine production with primed T lymphocytes on subsequent co-culture. Treatment of such antigen-bearing macrophages with trypsin, a procedure which removes surface antigen, does not alter the ability of such macrophage to initiate the release of migration inhibition factor from sensitized T lymphocytes. In addition, formation of antigen-specific rosettes between primed T cells and antigen-bearing macrophages is not blocked by high concentrations of antibody directed against the antigen mediating this interaction. Similarly, primed T lymphocyte DNA synthesis induced by antigen-bearing macrophages is not inhibited by specific antibody to that antigen. These data support the conclusion that the fraction of macrophage-associated antigen which is relevant to T lymphocyte activation does not reside on the macrophage surface but rather remains in a restricted compartment from which it is accessible to the T cell but unavailable to either blockade by specific antibody or removal by proteolytic enzymes.
D000818:Animals; D000941:Antigens; D002462:Cell Membrane / Q000276:immunology; D004136:Dinitrobenzenes / Q000276:immunology; D006168:Guinea Pigs; D008213:Lymphocyte Activation; D008263:Macrophage Migration-Inhibitory Factors / Q000096:biosynthesis; D008264:Macrophages / Q000276:immunology*; D012709:Serum Albumin / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D014357:Trypsin / Q000494:pharmacology
D000941:Antigens; D004136:Dinitrobenzenes; D008263:Macrophage Migration-Inhibitory Factors; D012709:Serum Albumin; D014357:Trypsin