In vitro infection with classical swine fever virus inhibits the transcription of immune response genes

Background: Classical swine fever virus (CSFV) can evade the immune response and establish chronic infection under natural and experimental conditions. Some genes related to antigen processing and presentation and to cytokine regulation are known to be involved in this response, but the precise mechanism through which each gene responds to CSFV infection remains unclear. Results: In this study, the amplification standard curve and corresponding linear regression equations for the genes SLA-2, TAP1, SLA-DR, Ii, CD40, CD80, CD86, IFN-alpha, and IFN-gamma were established successfully. Real-time RT-PCR was used to quantify the immune response gene transcription in PK-15 cells post CSFV infection. Results showed that: (1) immune response genes were generally down-regulated as a result of CSFV infection, and (2) the expression of SLA-2, SLA-DR, Ii and CD80 was significantly decreased (p<0.001). Conclusion: We conclude that in vitro infection with CSFV inhibits the transcription of host immune response genes. These findings may facilitate the development of effective strategies for controlling CSF.