A Novel 2006 Indian Outbreak Strain of Chikungunya Virus Exhibits Different Pattern of Infection as Compared to Prototype Strain

Abstract

BackgroundThe recent re-emergence of Chikungunya virus (CHIKV) in India after 32 years and its worldwide epidemics with unprecedented magnitude raised a great public health concern.Methods and FindingsIn this study, a biological comparison was carried out between a novel 2006 Indian CHIKV outbreak strain, DRDE-06 and the prototype strain S-27 in mammalian cells in order to understand their differential infection pattern. Results showed that S-27 produced maximum number of progenies (2.43E+06 PFU/ml) at 20 to 24 hours post infection whereas DRDE-06 produced more than double number of progenies around 8 hours post infection in mammalian cells. Moreover, the observation of cytopathic effect, detection of viral proteins and viral proliferation assay confirmed the remarkably faster and significantly higher replication efficiency of DRDE-06. Moreover, our mutational analysis of whole genome of DRDE-06 revealed the presence of nineteen mutations as compared to S-27, whereas the analysis of 273 global isolates showed the consistent presence of fifteen out of nineteen mutations in almost all outbreak isolates. Further analysis revealed that ∼46% of recent outbreak strains including DRDE-06 do not contain the E1-A226V mutation which was earlier shown to be associated with the adaptation of CHIKV in a new vector species, Aedes albopictus.ConclusionsA novel 2006 Indian CHIKV outbreak strain, DRDE-06 exhibits different pattern of infection as compared to prototype strain, S-27. This might be associated to some specific mutations observed in genome wide mutational analysis in DRDE-06 which emphasizes the need of future experimental investigation.

Development of novel antibodies against non-structural proteins nsP1, nsP3 and nsP4 of chikungunya virus: potential use in basic research

“…Similarly, in the present study, polyclonal antibodies against other nsPs of CHIKV (nsP1, nsP3 and nsP4) have been developed, characterized and evaluated as a tool for experimental studies using different biological techniques and an in vitro infection model in mammalian cells. These antibodies were also used to compare the protein profiles of two CHIKV strains (CHIKV prototype strain S 27 and 2006 Indian outbreak strain DRDE-06), supporting earlier reports of differences in their replication efficiency [37] and providing more insight into the process of replication of CHIKV.…”

“…Plaque assays were performed according to a procedure described previously [37,38]. The cells were fixed 3 to 4 days after infection and stained with crystal violet.…”

“…Virus titers of the supernatants were determined using a plaque assay [37,38]. Three independent experiments were performed, and the mean value was calculated.…”

Outbreak of Chikungunya virus in the north Caribbean area of Colombia: clinical presentation and phylogenetic analysis

“…It is important to identify the genotype involved in the Colombian outbreak because the presence of particular genotypes has been associated with more severe clinical manifestations, high pathogenicity or virulence, mortality, and even enhancement of mosquito infectivity [24].…”

Chikungunya Virus Interacts with Heat Shock Cognate 70 Protein to Facilitate Its Entry into Mosquito Cell Line

“…CHIKV strain DRDE-06 (GenBank accession number: EF210157.2), which does not contain the A226V mutation in the E1 gene, was used in this study [13]. CHIKV was propagated in Vero cells grown in Dulbecco's modified Eagle's media (DMEM) (Gibco, USA).…”