Inflammasome activation and pro-inflammatory cytokine genes expression following exposure of PPRV in vero cells

Peste des petits ruminants (PPR), a contagious and fatal infection of small ruminants, caused by PPR virus (PPRV). Detection of microbes is mediated by pattern recognition receptors (PRRs). These PRRs trigger the assembly of a multi-protein signaling platform known as inflammasome. It detects the pathogens and induces the synthesis of pro-inflammatory cytokines interleukins (IL) i.e. IL-1β and IL-18. Aim of present study was to assess the expression of inflammasome related genes, following exposure to PPRV in Vero Cells and was to assess the effect of activation of inflammasome on downstream pro-inflammatory cytokines IL-1β and IL-18 gene expression.

Vero cells were infected with PPRV. The cells were incubated for different periods. Total RNA was reverse transcribed and used for amplification by quantitative real time PCR (qRT-PCR) to detect the relative change in expression of NLRP3, ASC, Caspase-1 and cytokines IL-1β and IL-18 genes.

It was revealed that 1 MOI of PPRV was appropriate for NLRP3 inflammasome activation. NLRP3 and ASC showed an increased level of expression at 2-4 hrs post inoculation (hpi). While, the Caspase-1 showed biphasic expression on 2-4 and 24 hpi, further, in the synchrony to it, IL-1β and IL-18 gene expression were also found increased at 2-4 and 24 hpi.