RESUMO
Interferon-alpha was detected in IFN pool produced by human leukocytes in the presence of gamma-globulin fraction proteins, copper and zinc cations, and metal-modified gamma-globulins. The cytokine appeared in culture medium at early terms (24 h) of incubation, is characterized by acid resistance, and is neutralized by antibodies to IFN-alpha. The content of IFN-alpha in supernatants of induced leukocytes reached 60-90 pg/ml and correlated with antiviral activity of the samples. Zinc bound to human serum gamma-globulin attenuated and copper stimulated the realization of IFN-inducing characteristics of the protein at early terms of incubation.
Assuntos
Interferon-alfa/metabolismo , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Albumina Sérica/farmacologia , Soroglobulinas/farmacologia , gama-Globulinas/farmacologia , Células Cultivadas , Cobre/química , Humanos , Técnicas Imunoenzimáticas , Albumina Sérica/química , Albumina Sérica Humana , Soroglobulinas/química , Zinco/química , gama-Globulinas/químicaRESUMO
Samples of human serum gamma-globulin with specifically bound copper or zinc cations were studied in Mancini's radial immunodiffusion test with human antibodies to IgG (H+L). The intensity of antibody binding to zinc-modified protein was 10-20% higher in comparison with the reference sample, while detection of gamma-globulin with bound copper by antibodies was 20-30% lower than in the corresponding reference sample. Comparison with the results of native gamma-globulin testing indicates limitations of Mancini's method as the quantitative assay for practical diagnosis, because under certain clinical conditions the traditional method can give over- and underestimated results.
Assuntos
Análise Química do Sangue/métodos , Cátions/metabolismo , Metais/metabolismo , gama-Globulinas/análise , gama-Globulinas/metabolismo , Análise Química do Sangue/normas , Cátions/química , Cátions/farmacologia , Cobre/química , Cobre/metabolismo , Humanos , Metais/química , Metais/farmacologia , Concentração Osmolar , Ligação Proteica , Testes Sorológicos/métodos , Testes Sorológicos/normas , Zinco/química , Zinco/metabolismoRESUMO
Plasma gamma-globulin fraction proteins, copper and zinc cations, and metal-modified gamma-globulins induce the production of IFN by human leukocytes. Binding of zinc cations attenuates the realization of the IFN-inducing effects of human serum gamma-globulin, while binding of copper cations potentiated this effect. Activity of IFN and the dynamics of its production correspond to those in response to phytohemagglutinin stimulation. The pool of induced IFN contains acid-labile (up to 60%) and acid-stable (up to 40%) constituents. Anti-IFN-alpha antibodies do not modify activity of produced IFN. The results indicate the possibility of gamma-globulin conformation allowing stimulation or attenuation of the protein capacity to induce the production of IFN pool with predominant content of IFN-gamma.
Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Interferons/metabolismo , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , gama-Globulinas/química , gama-Globulinas/farmacologia , Células Cultivadas , Cobre/metabolismo , Humanos , Interferon gama/metabolismo , Ligação Proteica , Conformação Proteica , Zinco/metabolismo , gama-Globulinas/metabolismoRESUMO
Samples of human serum gamma-globulin modified by equimolar binding of copper and zinc cations were obtained using the method of molecular ultrafiltration. Conformation characteristics of the protein were studied by UV spectrophotometry. Immunochemical study included radial immunodiffusion test, direct and sandwich enzyme immunoassays. Conformation changes in gamma-globulin caused by incorporation of solitary metal cations into the protein molecule modified presentation of antigenic determinants on the globule surface and their availability for recognition by specific antibodies. New antigenic determinants and new antigenic specificity of gamma-globulin are not formed under these conditions.
Assuntos
Cobre/metabolismo , Zinco/metabolismo , gama-Globulinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Epitopos/química , Epitopos/imunologia , Epitopos/metabolismo , Humanos , Ligação Proteica , Conformação Proteica , Espectrofotometria Ultravioleta , gama-Globulinas/química , gama-Globulinas/imunologiaRESUMO
Binding of copper cations to human serum gamma-globulin was studied using molecular ultrafiltration. The content of free metal in the filtrate was evaluated by the reaction with sodium diethyldithiocarbamate. Conformation characteristics of the protein were evaluated by UV spectrophotometry. gamma-Globulin molecule has several copper-binding sites differing by binding constants and filled one-by-one as the content of bound metal increased.
