Abstract
BackgroundFlavivirus cross-reactive antibodies in human sera interfere with the definitive identification of dengue virus (DENV) infections especially in areas with multiple co-circulating flaviviruses. Use of DENV envelope domain-III (EDIII) can partially resolve the problem. This study has examined the effect of (i) incorporating the EDIIIs of four DENV serotypes into a single chimeric antigen, and (ii) immobilizing the antigen through specific interaction on the sensitivity and specificity of anti-DENV antibody detection.MethodsA sera panel (n = 164) was assembled and characterized using commercial kits for infection by DENV and a host of other pathogens. Anti-DENV antibodies of both IgM and IgG classes in this panel were detected in indirect ELISAs using a mixture of monovalent EDIIIs, a chimeric EDIII-based tetravalent antigen, EDIII-T, and a biotinylated version of the latter as coating antigens. The sensitivity and specificity of these assays were compared to those obtained using the PanBio Dengue IgG/IgM ELISAs.ResultsThe performance of dengue IgG and IgM indirect ELISAs, using either a physical mixture of four EDIIIs or the single chimeric EDIII-T antigen, were comparable. Coating of a biotinylated version of the tetravalent antigen on streptavidin plates enhanced sensitivity without compromising specificity.ConclusionsThe incorporation of the EDIIIs of the four DENV serotypes into a single chimeric antigen did not adversely affect assay outcome in indirect ELISAs. Oriented, rather than random, immobilization of the tetravalent antigen enhanced sensitivity of detection of anti-DENV antibodies with retention of 100% specificity.
Highlights
Flavivirus cross-reactive antibodies in human sera interfere with the definitive identification of dengue virus (DENV) infections especially in areas with multiple co-circulating flaviviruses
The major aims of this study were to (i) compare the performance of single envelope domain-III (EDIII)-T antigen with a physical mixture of monovalent EDIIIs corresponding to the four DENV serotypes; and, (ii) evaluate if oriented immobilization of the tetravalent antigen influences the sensitivity of detection of both IgG and IgM classes of anti-DENV antibodies, in indirect enzyme linked immunosorbent assays (ELISA)
Comparison of EDIII antigen mixture versus a single chimeric EDIII-T antigen in indirect ELISAs The reactivity of an antigen mixture comprising the EDIIIs of the four DENV serotypes towards anti-DENV antibodies was compared to that of a single tetravalent antigen incorporating all these four EDIIIs in a single molecule [5]. For this purpose indirect IgM and IgG ELISAs were performed using 164 human sera collected from endemic and non-endemic countries which were pre-characterized for the presence or absence of antiDENV IgM and IgG antibodies using a commercial kit from PanBio Diagnostics
Summary
Flavivirus cross-reactive antibodies in human sera interfere with the definitive identification of dengue virus (DENV) infections especially in areas with multiple co-circulating flaviviruses. As DENVs. Efforts to eliminate the problem of cross-reactivity have begun to focus on the utility of DENV envelope protein domain III (EDIII), as a diagnostic intermediate of high specificity [3,4,5]. Efforts to eliminate the problem of cross-reactivity have begun to focus on the utility of DENV envelope protein domain III (EDIII), as a diagnostic intermediate of high specificity [3,4,5] As this domain contains both serotype-specific as well as DENV complex-specific epitopes [6], it is necessary to utilize EDIIIs of all four DENV serotypes to detect anti-DENV antibodies.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
