PRRSV感染对猪肺泡巨噬细胞Bax和Bcl-2 mRNA表达的影响

Bax and Bcl-2 gene expression in porcine alveolar macrophages infected by porcine reproductive and respiratory syndrome virus

凋亡过程的启动直接决定了细胞的"命运"。在细胞凋亡的线粒体和死亡受体信号转导途径中,Bcl-2家族成员的构成比例是凋亡调控的关键因素,尤其是Bcl-2/Bax比率是启动细胞凋亡的"分子开关"。为研究Bcl-2和Bax在猪繁殖与呼吸综合征病毒(porcine reproductive and respiratory syndrome virus,PRRSV)感染过程中的表达情况,为PRRSV的发病机制研究积累资料,本试验以PRRSV的易感细胞—猪肺泡巨噬细胞(porcine alveolar macrophage,PAM)为试验材料,应用SYBR GreenⅠ实时定量PCR方法检测了PRRSV感染PAM后不同时间Bcl-2和Bax的表达变化。结果表明,与对照组相比,PRRSV感染PAM后6、12h,Bax的表达下降,而Bcl-2的表达升高;且12h时与对照组相比均差异显著(P<0.05);感染后24h,与对照组相比,Bax的表达基本无变化,而Bcl-2的表达降低且与对照组存在显著差异;感染后48h,Bax的表达升高而Bcl-2的表达降低,且与对照组均差异显著。提示感染初期,PRRSV为了自身的复制使细胞处于抑凋亡状态,而病毒感染的后期增加了细胞凋亡。

The beginning of apoptosis directly determines the cell＂destiny＂.In mitochondrial pathway and death receptor pathway of cell apoptosis,the composition of Bcl-2 family members,especially the ratio of Bcl-2/Bax,is＂molecular switch＂which starts the cell apoptosis.In order to detect Bcl-2 and Bax gene expression in porcine alveolar macrophages infected by porcine reproductive and respiratory syndrome virus（PRRSV）and accumulate data for PRRSV＇s pathogenesis research.We detected Bax and Bcl-2 mRNA expression in porcine alveolar macrophages infected by porcine reproductive and respiratory syndrome virus by SYBR GreenⅠ real-time PCR method.The results showed that at 6h and 12h after PRRSV infected,Bax expression decreased while Bcl-2 expression increased compared with those of not infected PAM.What＇s more,those of 12h infected PAM had significant difference compared with those of control group.At 24h after inoculation,Bax expression had no noticeable change,but Bcl-2 expression reduced and had significant difference compared with those of control group.At 48h after inoculation,Bax expression improved and Bcl-2 expression reduced and all had significant difference compared with those of control group.Those results suggested that the cells were in condition of suppression apoptosis at the beginning of PRRSV infection and it was conducive to PRRSV replication.However,cell apoptosis was increased at late stage of PRRSV infection.