Detection of Differential Expression of Porcine IFN- α Subtypes by Reverse Transcription Polymerase Chain Reaction

The porcine interferon-α (IFN-α) multigene family is a new IFN-α system in recent research. Characterization of the PoIFN-α multigene family has been described in our previous work, and 14 functional PoIFN-α genes were detected in the porcine genome. In this study, we designed subtype-specific primers and consensus primers for PoIFN-α. The expression of PoIFN-α was detected using the two PCR strategies in three systems, namely, poly(I).poly(C)-DEAE-dextran-induced PK15 cells, pseudorabies virus-infected PK15 cells, and infected PK15 cells with an attenuated strain of swine fever virus, respectively. In poly(I).poly(C)-DEAE-dextran-induced PK15 cells, the expression of IFN-α2, -α3, -α4, -α8, and -α9 after 6-h/24-h inducement in PK15 cells were observed. In pseudorabies virus-infected PK15 cells, the expression of PoIFN-α2, -α3, -α8, -α9, -α10, and -α13 was observed after 6-h/24-h infection, and in the attenuated strain of swine fever virus-infected PK15 cells, upregulation of PoIFN-α2, -α3, -α4, -α8, -α9, and -α10 was detected. The results of realtime quantitative PCR analysis suggested that the expression was time-dependent in pseudorabies virus/poly(I).poly(C)-DEAE-dextran-induced PK15 cells, but in the attenuated swine fever virus-infected PK15 system, the expression level of IFN-α subtypes was not obviously time dependent.