An assay capable of distinguishing between the immune response generated by recent exposure to rubella virus and the immune response existing as a result of past exposure or immunization is required for the diagnosis of primary rubella virus infection, especially in pregnant women. Avidity assays, which are based on the premise that chaotropic agents can be used to selectively dissociate the low-avidity antibodies generated early in the course of infection, have become routinely used in an effort to accomplish this. We have thoroughly investigated the immunological basis of an avidity assay using a viral lysate-based assay and an enzyme-linked immunosorbent assay (ELISA) based on a peptide analogue of the putative immunodominant region of the E1 glycoprotein (E1 208-239 ). The relative affinities of the antibodies directed against E1 208-239 were measured by surface plasmon resonance and were found to correlate well with the avidity index calculated from the ELISA results. We found that the immune response generated during primary rubella virus infection consists of an initial low-affinity peak of immunoglobulin M (IgM) reactivity followed by transient peaks of low-avidity IgG3 and IgA reactivity. The predominant response is an IgG1 response which increases in concentration and affinity progressively over the course of infection. Incubation with the chaotropic agent used in the avidity assay abolished the detection of the early low-affinity peaks of IgM, IgA, and IgG3 reactivity while leaving the high-affinity IgG1 response relatively unaffected. The present study supported the premise that avidity assays based on appropriate antigens can be useful to confirm primary rubella virus infection.Rubella virus is a positive-sense, single-stranded RNA virus belonging to the Togaviridae family in the genus Rubivirus (17). Infection with rubella virus usually results in a mild disease that only rarely produces significant sequelae. However, primary rubella virus infection during the first trimester of pregnancy may result in the transmission of virus through the placenta and infection of the fetus. This may in turn result in congenital rubella syndrome (CRS), the most common manifestations of which are blindness, mental retardation, and deafness (15). The risk of the fetus developing CRS is 40 to 60% if infection occurs during first two months of pregnancy, 35 to 40% if it occurs in the third month of pregnancy, and 10% if it occurs in the fourth month of pregnancy (19).Rubella virus infection occurs worldwide, with a seasonal peak of infections in spring in temperate climates. Globally, only 57% of countries have rubella vaccination programs, and it is estimated that more than 100,000 cases of CRS occur each year in developing countries (27).The humoral immune response to infection commences with the production of low-affinity immunoglobulin M (IgM) molecules. Class switch recombination then results in the generation of antibody isotypes with the appropriate effector function to eliminate the invading organism. Concurre...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.