猪瘟病毒C株共感染口蹄疫病毒影响口蹄疫病毒复制

Co-infection of classical swine fever virus C strain and foot-and-mouth disease virus affects foot-and-mouth disease virus replication

摘要:

【背景】猪瘟(Classical Swine Fever)是由猪瘟病毒(Classical Swine Fever Virus，CSFV)引起的猪高度接触性传染病，致死率极高。在临床中存在着CSFV与猪其他病原菌共感染的情况，例如CSFV与口蹄疫病毒(Foot-and-Mouth Disease Virus，FMDV)的共感染。【目的】利用CSFV与FMDV共感染猪源宿主细胞，研究CSFV与FMDV共感染对FMDV病毒复制的影响。【方法】构建体外共感染细胞模型，在正常PK-15细胞上进行CSFV共感染FMDV实验，通过观察细胞病变效应(Cytopathic Effect，CPE)、实时荧光定量PCR (RT-qPCR)、Western Blot、间接免疫荧光检测CSFV和FMDV共感染及FMDV单独感染情况下FMDV复制水平的差异。利用RT-qPCR筛选鉴定能够影响FMDV复制的CSFV蛋白。【结果】CSFV C株共感染FMDV能够抑制FMDV的复制，而且灭活的CSFV同样抑制FMDV的复制。通过筛选鉴定出CSFV的C蛋白能够抑制FMDV复制。【结论】研究发现CSFV C株共感染FMDV能够抑制FMDV复制，而其C蛋白具有抑制FMDV复制的能力。

Abstract:

[Background] Classical swine fever is caused by classical swine fever virus (CSFV), which is highly contagious and fatal to pigs. Co-infection of CSFV with other swine pathogens is present in clinical practice, such as, CSFV is co-infected with foot-and-mouth disease virus (FMDV) in pigs. [Objective] The effects of co-infection of CSFV and FMDV in porcine host cells on replication of FMDV were studied. [Methods] We constructed an in vitro model of co-infection of CSFV and FMDV. The PK-15 cells were first infected with CSFV and then infected with FMDV. The replication of FMDV in FMDV-infected cells and the cells with co-infection of CSFV and FMDV was analyzed by cytopathic effect, real-time quantification PCR (RT-qPCR), Western Blot and indirect immunofluorescence assay, respectively. The CSFV proteins that included the inhibitive function on FMDV replication was subsequently screened by RT-qPCR analysis. [Results] Co-infection of CSFV C strain and FMDV inhibited the replication of FMDV. Meanwhile, the inactivated CSFV also showed inhibitive activity on FMDV replication. A detailed screening identified that CSFV C protein include the function to suppress FMDV replication. [Conclusion] We found that CSFV C strain infection could inhibit FMDV infection, and the C protein of CSFV included a function to inhibit FMDV replication.