Fig. 6.

Type I interferon and innate viral sensing gene response in IBV infected chicken embryo tracheal organ cultures (TOCs). Relative mRNA expression of (A) INF-α, (B) INF-β, (C) TLR3, (D) TLR7 in TOCs infected with IBV strains 885, QX, or M41 at a dose of 4log₁₀ CD₅₀ per individual ring or mock-infected and gene expression was analysed at 9 and 24 hpi (hours post-infection). Relative mRNA expression was determined by real-time PCR normalised to 18S rRNA. Graphed values are the mean of three biological replicates with error bars as standard error and are expressed as fold change relative to the mocked-infected group. Different letters indicate that the differences between groups at that time point are significant (p<0.05).