Distinct reactivities of four monoclonal antibodies with human interleukin 2 receptor.
Two new murine monoclonal IgG1 antibodies, H-31 and H-A26, were characterized in comparison with two previously obtained monoclonal antibodies against human interleukin 2 (IL-2) receptor (IL-2 R), anti-Tac and HIEI. In immunofluorescence assays with various human hematopoietic cells, H-31 and H-A26 antibodies both reacted with only IL-2 R-positive cells, and they precipitated IL-2 R molecules, glycoproteins with molecular weights of 60K and 53K daltons (gp60/gp53), from human T-cell leukemia virus type I (HTLV-I)-carrying MT-2 cells, as demonstrated by sequential immunoprecipitation after absorption of IL-2 R with anti-Tac. Antibody-binding competition assays showed that H-31 and anti-Tac, and H-A26 and HIEI, respectively, competed reciprocally in binding to the cells, and that anti-Tac also inhibited the binding of HIEI but not vice versa. H-31, like anti-Tac, strongly inhibited the IL-2-dependent proliferation of normal activated T-cells, absorption of IL-2 and direct binding of IL-2 to the cells, while H-A26, like HIEI, inhibited those processes only weakly. The spectra of reactivities of these antibodies with various simian cell lines derived by HTLV-I infection were different, as revealed by immunofluorescence studies. Human IL-2 R was shown to express a unique antigenic determinant, detected with HIEI, that was not detectable in IL-2 R molecules of Old and New World monkeys, and also to express determinants common to simian IL-2 R molecules. These observations indicate that H-31 and H-A26 recognize human IL-2 R molecules and that the antigenic sites on the IL-2 R molecule defined by H-31, H-A26, anti-Tac, and HIEI are different.
Tanaka
Y
Y
Tozawa
H
H
Hayami
M
M
Sugamura
K
K
Hinuma
Y
Y
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000918:Antibody Specificity; D000954:Antigens, Surface / Q000276:immunology; D001667:Binding, Competitive; D002472:Cell Transformation, Viral; D017977:Deltaretrovirus; D000939:Epitopes / Q000276:immunology; D000882:Haplorhini; D006801:Humans; D008213:Lymphocyte Activation; D051379:Mice; D010835:Phytohemagglutinins / Q000494:pharmacology; D011971:Receptors, Immunologic / Q000276:immunology*; D015375:Receptors, Interleukin-2; D013045:Species Specificity; D013601:T-Lymphocytes / Q000276:immunology; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7
D000911:Antibodies, Monoclonal; D000954:Antigens, Surface; D000939:Epitopes; D010835:Phytohemagglutinins; D011971:Receptors, Immunologic; D015375:Receptors, Interleukin-2; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7