title: Selective killing of target cells by antibody-ricin A chain or antibody-gelonin hybrid molecules: comparison of cytotoxic potency and use in immunoselection procedures.
abstract: Ricin A chain and gelonin, two plant proteins that can powerfully reduce the protein synthetic capacity of ribosome preparations, were covalently coupled to a monoclonal anti-Thy-1.2 antibody. Two conjugates were prepared by using N-succinimidyl-3-2(-pyridyldithio)propionate, which generates a disulfide linkage between the component molecules. Both conjugates specifically killed Thy-1.2 antigen-bearing EL-4 cells, but had no effect on Thy-1.2- BW5147 cells. The cytotoxic potency of both reagents was determined by comparing the cloning efficiency of E1-4 target cells after treatment with the conjugate. The frequency of cells surviving treatment with 45 micrograms/10(6) cells of the gelonin conjugate was 1/72, whereas this frequency was 1/836 after exposure to 7 micrograms of the Ricin A chain conjugate. Both reagents could be successfully used to select Thy-1.2- cells from cell mixtures consisting of Thy-1.2+ and Thy-1.2- cells.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000918:Antibody Specificity; D000920:Antibody-Dependent Cell Cytotoxicity; D000954:Antigens, Surface / Q000032:analysis; D000961:Antilymphocyte Serum / Q000494:pharmacology; D002460:Cell Line; D002470:Cell Survival; D006825:Hybridomas / Q000276:immunology; D051379:Mice; D008819:Mice, Nude; D010940:Plant Proteins / Q000276:immunology*; D054789:Ribosome Inactivating Proteins, Type 1; D012276:Ricin / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology; D018800:Thy-1 Antigens
chemical_list: D000911:Antibodies, Monoclonal; D000954:Antigens, Surface; D000961:Antilymphocyte Serum; D010940:Plant Proteins; D054789:Ribosome Inactivating Proteins, Type 1; D018800:Thy-1 Antigens; C025674:GEL protein, Gelonium multiflorum; D012276:Ricin