Development of a novel rapid micro-neutralization ELISA for the detection of neutralizing antibodies against Chandipura virus

摘要

Background: Chandipura virus (CHPV) is a leading cause of acute encephalitis with high mortality in paediatric population in India. A micro-neutralization ELISA (MN-ELISA) assay was developed for the detection of neutralizing antibodies (Nab) against CHPV. This novel method gives read-out in the form of ELISA optical density (OD) values and has a shorter turn-around time (TAT) as compared to the conventional cytopathic effect (CPE)-based neutralization assay (MN-CPE). The assay was developed using an Indian strain of CHPV. During the development of the assay different parameters such as cell count, dilution of primary and secondary antibodies and time point for the test termination were optimized. The new and conventional assays were run in parallel where known positive and negative human serum samples were used as test controls. The conventional MN-CPE was terminated at 48 h post-infection (p.i.) and stained with Amido black, while in the new assay, MN-ELISA was terminated at pre-determined 18 h p.i. and the infected cells were fixed with acetone, followed by in-situ ELISA. Results of both the assays were compared.