A neutralization test for specific detection of Nipah virus antibodies using pseudotyped vesicular stomatitis virus expressing green fluorescent protein

Abstract

Nipah virus (NiV) is a new zoonotic paramyxovirus that emerged in 1998 and is now classified in the genus Henipavirus along with the closely related Hendra virus (HeV). NiV is highly pathogenic in several vertebrate species including humans, and the lack of available vaccines or specific treatment restricts it to biosafety level 4 (BSL4) containment. A serum neutralization test was developed for measuring NiV neutralizing antibodies under BSL2 conditions using a recombinant vesicular stomatitis virus (VSV) expressing green fluorescent protein (GFP) and bearing the F and G proteins of NiV (VSV-NiV-GFP). The neutralization titers were obtained by counting GFP-expressing cells or by measuring fluorescence. The performance of this new assay was compared against the conventional test using live NiV with panels of sera from several mammalian species, including sera from NiV outbreaks, experimental infections, as well as HeV-specific sera. The results obtained with the VSV-NiV-GFP based test correlated with those obtained using live NiV. Using a 50% reduction in VSV-NiV-GFP infected cells as the cut-off for neutralization, this new assay demonstrated its potential as an effective tool for detecting NiV neutralizing antibodies under BSL2 containment with greater speed, sensitivity and safety as compared to the conventional NiV serum neutralization test.

Complementing Defective Viruses That Express Separate Paramyxovirus Glycoproteins Provide a New Vaccine Vector Approach

“…To measure titers of nAbs to NiV G or F proteins, we used VSV⌬G-eGFP1 (19) pseudotyped with NiV G and F proteins. This is a neutralization assay similar to that described by others, which correlates well with direct determination of NiV neutralization titers (17,34).…”

Nipah virus infection: current scenario

“…Inf. Diseases, Japan [49] 17. Recombinant matrix protein produced in E. coli University Putra Malaysia Malaysia [82] 18.…”

Development and validation of serological assays for viral hemorrhagic fevers and determination of the prevalence of Rift Valley fever in Borno State, Nigeria

“…This assumption is supported by the observation that the NAb titers measured using pseudotyped VSV bearing the GP of Nipah virus or SARS-coronavirus are higher than those obtained by using infectious viruses. 21,29,30 The ROC and TG-ROC analyses indicated an appropriate cut-off value for the percent neutralization (75%) to demonstrate that the NAbs in the sera had high sensitivity and specificity. The conventional assay for measuring NAbs requires serial-dilutions of the test serum and takes several days for the virus to replicate to a level which results in plaque-forming or cytopathic effects in infected cells.…”