Cytokine expression in three chicken host systems infected with H9N2 influenza viruses with different pathogenicities.

Cytokine expression in three chicken host systems infected with H9N2 influenza viruses with different pathogenicities. Avian Pathol. 2016 Dec;45(6):630-639 Authors: Wang J, Cao Z, Guo X, Zhang Y, Wang D, Xu S, Yin Y Abstract SD/818 and SD/196 are H9N2 influenza virus strains isolated from chickens from the same farm at different times that exhibited similar genetic evolution. However, strain SD/818 exhibited higher pathogenicity in chickens than strain SD/196 and other H9N2 influenza virus epidemic strains from China. The expression of cytokines is an important host defence mechanism following viral infection and their intensity is a major determinant of viral pathogenicity. To elucidate the mechanism underlying the increased pathogenicity of strain SD/818 from the host's perspective, viral replication and cytokine expression were dynamically studied using real-time quantitative reverse transcription PCR in chickens infected with strain SD/818 compared with chickens infected with strain SD/196 in this study. The results showed that the replication of strain SD/818 and the expressions of IL-1β, IL-6, TNF-α, IFN-α and IFN-β induced by strain SD/818 were higher than those induced by strain SD/196 in the chicken host system. Expression of these cytokines in chickens coincided with or followed virus replication. These results suggested that high-level viral replication and pro-inflammatory cytokine expression (but not decreased type I...
Source: Avian Pathology - Category: Pathology Authors: Tags: Avian Pathol Source Type: research