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 response in both postnatal and vaccinal RV infections, being much weaker in the vaccinal ones. The IgG response to the recombinant C protein was very strong after the first month post infection and decreased with time. The immune response 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.
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 response in both postnatal and vaccinal RV infections, being much weaker in the vaccinal ones. The IgG response to the recombinant C protein was very strong after the first month post infection and decreased with time. The immune response 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.
Authors: Terri B Hyde; Helena Keico Sato; LiJuan Hao; Brendan Flannery; Qi Zheng; Kathleen Wannemuehler; Flávia Helena Ciccone; Heloisa de Sousa Marques; Lily Yin Weckx; Marco Aurélio Sáfadi; Eliane de Oliveira Moraes; Marisa Mussi Pinhata; Jaime Olbrich Neto; Maria Cecilia Bevilacqua; Alfredo Tabith Junior; Tatiana Alves Monteiro; Cristina Adelaide Figueiredo; Jon K Andrus; Susan E Reef; Cristiana M Toscano; Carlos Castillo-Solorzano; Joseph P Icenogle Journal: J Infect Dis Date: 2014-10-31 Impact factor: 5.226
Authors: Wayne Dimech; Lena Panagiotopoulos; Barbara Francis; Nicholas Laven; Joan Marler; David Dickeson; Tony Panayotou; Kim Wilson; Robyn Wootten; Elizabeth M Dax Journal: J Clin Microbiol Date: 2008-04-23 Impact factor: 5.948