Identification of Whole Blood Transcriptome and QTLs/eQTLs in Pigs with Extreme in vivo dsRNA-Induced Serum IFN-A

A number of QTL studies have been conducted in the pig, but few studies focused on anti-viral immune response. In this study, identification of transcriptome , QTLs / eQTLs for anti-viral immune response in the pig were performed in a Duroc-Erhualian F2 population. Poly (I:C), a synthetic analog of double-stranded RNA, which can induce interferon and enhance the capability of disease resistance to various viral pathogens, were used to trigger the potential immune capability for each F2 pig. For each F2 pig, blood samples were harvested by jugular venipuncture at 20, 33 and 35 days old. The stimulation with 0.5mg/kg poly (I:C) for each pig at 4 hours before drawing blood at 35 days old. Hematological parameters, blood T-cell subgroup and serum cytokines were measured for all samples. All the F2 and F1 pigs were genotyped by Illumina porcine 60k SNP chips. Interesting chromosome regions harboring QTLs for some T-cell subgroup traits were found. The interesting eQTL regions for IFNA and IFNG were found as well. The interferon-dependent antiviral responsiveness through the IFN-stimulated genes (ISGs) was found more effective in pigs with high dsRNA-induced serum IFN-a, it was likely due to the enhanced expression of IRF-7 in TLR or RIG- I/MDA5 signaling pathways.