Immunity surveillance of mumps and rubella: improved methods for the detection of virus-specific antibody

摘要

The aim of these studies was to improve laboratory methods for the detection of virus-specific antibody to mumps and rubella. The presence of virus-specific antibody is indicative of immunity to disease so simple and effective antibody detection allows for the planning and monitoring of immunisation programmes.ududIn facilitating antibody surveillance, oral fluid has advantages as a sample compared with blood. It is simple, safe and cheap to collect and being non-invasive encourages subject recruitment. In this study, an ‘IgG’ antibody capture enzyme-linked immunosorbent assay (GACELISA) was developed and evaluated for the detection of mump-specific IgG in oral fluid. Compared to an indirect commercial ELISA for the detection of mumps-specific IgG in serum, the oral fluid GACELISA was 100% sensitive and specific. The GACELISA should therefore be useful for future antibody prevalence studies.ududThe limitation of oral fluid samples compared with blood are that they contain lower antibody concentrations. Immuno-polymerase chain reaction (I-PCR) is an ultrasensitive method and in this study was adapted to detect antibodies to mumps virus. Though the method was shown to be feasible for antibody detection and quantification, its sensitivity and specificity did not exceed that of a conventional ELISA. Sensitivity was limited by non-specific binding of human IgG to the solid phase. It is necessary to further develop reagents and assay formats to fully exploit the potential of quantitative I-PCR, so that potential improvements in the sensitivity of viral-specific IgG detection can be realised.ududIncreasingly, recombinant antigens are being employed in ELISAs as cell culture antigens are difficult and expensive to produce, and are potentially infectious. In this study, the PinPoint Xa-1 T-Vector system was used to produce recombinant rubella virus (RV) El fusion proteins in Escherichia coli. Their antigenicity was assessed by Western blotting and ELISA. One of these antigens may be a suitable reagent for immunity studies as it reacted with RV El-specific monoclonal antibodies (MAb's) and a high percentage (80%) of RV antibody positive sera.