title: Nature of the antigenic complex recognized by T lymphocytes. IX. Direct immunochemical demonstration of nominal antigen on the macrophage cell surface.
abstract: As an initial approach to macrophage (M phi) antigen handling, guinea pig M phi pulsed with the radiolabeled terpolymer L-glutamic acid, L-lysine, L-tyrosine (GLT) were modified with the cell surface-specific probe 2,4,6-trinitrobenzenesulfonic acid either immediately after pulsing (fresh) or 24 h after pulsing (aged); nonidet P-40 extracts were prepared from these cells and analysis of these extracts with anti-trinitrophenyl antisera was performed in a quantitative radioimmunoassay. Such experiments indicated that fresh GLT-pulsed M phi contained a pool of intracellular GLT as well as a distinct pool of cell surface GLT. In contrast, aged GLT-pulsed M phi lacked intracellular GLT but expressed GLT on the cell surface. In addition, a pool of cell surface GLT was also detected on Ia-M phi and on M phi from guinea pigs which were nonresponders to GLT. Thus, this study provides a direct demonstration of the presence of exogenous antigen on the M phi cell surface. However, the cell surface expression of GLT does not appear to be an exclusive property expressed by functional Ia+ antigen-presenting M phi.
mesh_terms: D000818:Animals; D000954:Antigens, Surface / Q000032:analysis* / Q000235:genetics / Q000276:immunology; D002470:Cell Survival; D004306:Dose-Response Relationship, Immunologic; D005802:Genes, MHC Class II; D006168:Guinea Pigs; D006433:Hemocyanins / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D008264:Macrophages / Q000032:analysis* / Q000378:metabolism; D017830:Octoxynol; D010455:Peptides / Q000276:immunology; D011092:Polyethylene Glycols / Q000494:pharmacology; D011108:Polymers; D011863:Radioimmunoassay; D013601:T-Lymphocytes / Q000032:analysis / Q000276:immunology* / Q000378:metabolism; D014301:Trinitrobenzenes / Q000276:immunology
chemical_list: D000954:Antigens, Surface; D000949:Histocompatibility Antigens Class II; D010455:Peptides; D011108:Polymers; D014301:Trinitrobenzenes; C022272:glutamic acid-lysine-tyrosine terpolymer; D011092:Polyethylene Glycols; D017830:Octoxynol; D006433:Hemocyanins; C010615:Nonidet P-40