口蹄疫病毒感染后猪PD-1及其配体转录水平变化和免疫抑制机制分析OA北大核心CSTPCD

This study investigated the mRNA transcription levels of programmed death-1(PD-1)and its ligands(PD-L1,PD-L2),cytokines[interleukin-2(IL-2),interleukin-10(IL-10),interferon-γ(IFN-γ)],and proliferation ability of peripheral blood mononuclear cells(PBMCs)in pigs infected with foot and mouth disease virus(FMDV),to explore the mechanism of the PD-1/PD-Ls pathway in the immunosuppressive process induced by FMDV.The results showed that at 3,7,14 and 17 days after infection with FMDV,the transcription level of PD-1 mRNA significantly or extremely significantly increased,reaching a peak at 7 days after infection,and then gradually decreased.At 3 and 7 days after infection with FMDV,the transcription level of PD-L1 mRNA extremely significantly increased.At 3 days after infection with FMDV,the transcription level of PD-L2 mRNA significantly increased.At 3 and 7 days after infection with FMDV,the transcription level of IL-2 mRNA significantly decreased.At 1 and 3 days after infection with FMDV,the transcription levels of IFN-γ mRNA extremely significantly decreased.The change trend of transcription levels of IL-2 and IFN-γ mRNA showed opposite to those of PD-1 and its ligands mRNA.At 3,7 and 14 days after infection with FMDV,the transcription level of IL-10 mRNA significantly or extremely significantly increased,which was consistent with the change trend of the transcription levels of PD-1 and its ligands mRNA.After infection with FMDV,the viral load of FMDV in the whole blood gradually increased with the progression of infection time,reaching a peak at 7 days after infection,which was generally consistent with the change trend of PD-1 and its ligand mRNA transcription levels.At 7 days after infection,the proliferation ability of PBMCs obviously decreased.Overall,after FMDV infection,the transcription levels of PD-1 and its ligands mRNA are upregulated,which is an important pathogenic mechanism for immune suppression caused by FMDV infection.