Characterization of IL-6 receptor expression by monoclonal and polyclonal antibodies.
mAb and polyclonal antibodies against human IL-6R were prepared by using a murine transfectant cell line expressing the human IL-6R and a synthetic oligopeptide made on the basis of the deduced amino acid sequence as immunogens. Immunoprecipitation of radiolabeled IL-6R with these antibodies showed that the Mr of a mature IL-6R was 80 kDa and its value was reduced to 50K after treatment with O- and N-glycanase and neuraminidase, indicating that IL-6R is a glycoprotein. Two mAb recognizing different epitopes were prepared. One, PM1 inhibited the binding of 125I-IL-6 to the receptor and blocked the IL-6-dependent growth of a T lymphoma line, KT3. PM1 could not bind to IL-6R when it was saturated with IL-6, indicating that this antibody recognizes the IL-6 binding or the adjacent site on IL-6R. The other, MT18 was not inhibited by IL-6 for its recognition of IL-6R, therefore, this could be used for cytofluorometric staining of normal cells. Nonstimulated B cells expressed undetectable amount of IL-6R regardless of the expression of surface IgD. However, after the stimulation with PWM, IL-6R was observed on IgD- B cells with a relatively large size, but subtly on IgD- small B cells and not on IgD+ B cells, fitting the function of IL-6 which acts on activated B cells to induce Ig production. In contrast, IL-6R was detected on non-stimulated CD4+/CD8- and CD4-/CD8+ T cells. The level of IL-6R on both T cell subpopulations was not significantly changed after stimulation with phytohemagglutinin.
Hirata
Y
Y
Division of Immunology, Osaka University, Japan.
Taga
T
T
Hibi
M
M
Nakano
N
N
Hirano
T
T
Kishimoto
T
T
D000911:Antibodies, Monoclonal / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D001667:Binding, Competitive; D005455:Fluorescent Antibody Technique; D006801:Humans; D015850:Interleukin-6 / Q000502:physiology*; D008562:Membrane Glycoproteins / Q000276:immunology*; D008970:Molecular Weight; D011233:Precipitin Tests; D011971:Receptors, Immunologic / Q000276:immunology / Q000502:physiology; D019947:Receptors, Interleukin-6; D013601:T-Lymphocytes / Q000276:immunology*; D014162:Transfection
D000911:Antibodies, Monoclonal; D015850:Interleukin-6; D008562:Membrane Glycoproteins; D011971:Receptors, Immunologic; D019947:Receptors, Interleukin-6