Browsing by Author "Oker-Blom, Christian (7004056386)"

Background: The three structural proteins of rubella virus (RV), the capsid protein C and the envelope glycoproteins E1 and E2, were produced individually in soluble form in Sf9 insect cells using the baculovirus system. All proteins were equipped with a polyhistidine tag at their C-terminal ends to enable gentle purification by metal ion affinity chromatography. In addition, the E1 and E2 proteins were engineered to display the FLAG epitope tag at their N-terminal ends. Study design: The diagnostic potential of the recombinant purified proteins was evaluated by immunoblot and enzyme immuno assays (EIA) using a total of 57 well-characterised serum samples obtained at various time points after natural RV infection, congenital rubella syndrome (CRS), MMR vaccination or from controls with past RV immunity. In addition, acute and convalescent phase serum pools from a total of 20 patients were evaluated. Authentic RV proteins were used as a reference. Results: The recombinant E1 and C proteins were predominant in eliciting the immune responce in both postnatal and vaccinal RV infections, being much weaker in the vaccinal ones. The IgG responce to the recombinant C protein was very strong after the first month post infection and decreased with time. The immune responce against the recombinant E2 protein, however, was generally poor, but notably stronger after congenital infection. Together, the results showed that the individual recombinant protein antigens could be suitable for diagnosis of RV infection and for study of the immune response to rubella vaccination. Copyright (C) 1999 Elsevier Science B.V.

Background: The three structural proteins of rubella virus (RV), the capsid protein C and the envelope glycoproteins E1 and E2, were produced individually in soluble form in Sf9 insect cells using the baculovirus system. All proteins were equipped with a polyhistidine tag at their C-terminal ends to enable gentle purification by metal ion affinity chromatography. In addition, the E1 and E2 proteins were engineered to display the FLAG epitope tag at their N-terminal ends. Study design: The diagnostic potential of the recombinant purified proteins was evaluated by immunoblot and enzyme immuno assays (EIA) using a total of 57 well-characterised serum samples obtained at various time points after natural RV infection, congenital rubella syndrome (CRS), MMR vaccination or from controls with past RV immunity. In addition, acute and convalescent phase serum pools from a total of 20 patients were evaluated. Authentic RV proteins were used as a reference. Results: The recombinant E1 and C proteins were predominant in eliciting the immune responce in both postnatal and vaccinal RV infections, being much weaker in the vaccinal ones. The IgG responce to the recombinant C protein was very strong after the first month post infection and decreased with time. The immune responce against the recombinant E2 protein, however, was generally poor, but notably stronger after congenital infection. Together, the results showed that the individual recombinant protein antigens could be suitable for diagnosis of RV infection and for study of the immune response to rubella vaccination. Copyright (C) 1999 Elsevier Science B.V.

Background: the structural proteins of rubella virus, the capsid protein C and the envelope glycoproteins E1 and E2 were produced in lepidopteran insect cells using baculovirus expression vectors. The C-terminal ends of the corresponding proteins were fused to a polyhistidine tag for easy and gentle purification by metal ion affinity chromatography. Objectives: to investigate the maturation of natural and vaccinal IgG avidity against individual authentic and recombinant rubella virus (RV) structural proteins. Study design: the analysis was carried out using a modified immunoblotting technique where the purified baculovirus-expressed proteins were compared with authentic rubella virus proteins. Altogether, 47 well-characterised serum samples from both naturally infected patients and vaccines were studied. Results: after natural RV infection, IgG antibodies specific for the E1 protein were predominant not only in terms of levels, but also in terms of rate and magnitude of avidity maturation. The avidity development of the IgG antibodies was much slower in vaccines than in patients after a natural RV infection. Conclusions: together, our results indicate that IgG avidity determination in conjunction with immunoblot analysis is useful in the diagnosis of a RV infection. The recombinant proteins showed similar reactivity patterns in the immunoblot analyses as compared with the authentic viral structural proteins, suggesting suitability for serodiagnostics. Copyright © 2001 Elsevier Science B.V.

Background: the structural proteins of rubella virus, the capsid protein C and the envelope glycoproteins E1 and E2 were produced in lepidopteran insect cells using baculovirus expression vectors. The C-terminal ends of the corresponding proteins were fused to a polyhistidine tag for easy and gentle purification by metal ion affinity chromatography. Objectives: to investigate the maturation of natural and vaccinal IgG avidity against individual authentic and recombinant rubella virus (RV) structural proteins. Study design: the analysis was carried out using a modified immunoblotting technique where the purified baculovirus-expressed proteins were compared with authentic rubella virus proteins. Altogether, 47 well-characterised serum samples from both naturally infected patients and vaccines were studied. Results: after natural RV infection, IgG antibodies specific for the E1 protein were predominant not only in terms of levels, but also in terms of rate and magnitude of avidity maturation. The avidity development of the IgG antibodies was much slower in vaccines than in patients after a natural RV infection. Conclusions: together, our results indicate that IgG avidity determination in conjunction with immunoblot analysis is useful in the diagnosis of a RV infection. The recombinant proteins showed similar reactivity patterns in the immunoblot analyses as compared with the authentic viral structural proteins, suggesting suitability for serodiagnostics. Copyright © 2001 Elsevier Science B.V.