鸭呼肠孤病毒感染雏鸭后炎症因子与脾脏损伤之间的动态关系

Dynamic relationship between inflammation cytokines and splenic injury in duckling infected with duck reovirus

分析鸭呼肠孤病毒(DRV)人工感染雏鸭后病毒的复制、NF-κB、TNF-α、IL-6与脾脏损伤之间的动态关系,初步探讨DRV感染机制和病毒与宿主之间的作用关系,为DRV致病机制的研究提供一定理论基础。运用HE染色对脾脏损伤程度进行分级,免疫组化定位病毒所在位置,并运用qRT-PCR检测分析DRV、NF-κB、TNF-α及IL-6的相对表达量。HE染色结果显示,DRV感染后1d脾脏出现肿胀、出血,感染后5d出现坏死,随后形成“肉芽肿”结构,坏死灶较小的已经完全机化;免疫组化结果显示,DRV主要存在于巨噬细胞;qRT-PCR结果显示,NF-κB和TNF-α相对表达量均是在感染后5d达到峰值,IL-6从感染后3d开始上调,且感染后7d表达上调显著。结果表明,雏鸭感染DRV后病毒主要存在于巨噬细胞,且脾脏损伤与病毒的复制呈正相关;细胞因子NF-κB、TNF-α和IL-6在感染过程中表达上调,进而引发炎症反应,说明DRV感染雏鸡后引起脾脏损伤的过程中NF-κB、TNF-α和IL-6起着重要作用。

The dynamic relationship between replication of the virus,NF-κB,TNF-α,IL-6and spleen injury when duckling was artificially infected with the duck reovirus(DRV)was analyzed.The mechanism of the DRV infection and the interaction relationship between the virus and its host were explored initially,to provide a theoretical basis for DRV pathogenic mechanism.The experimental contents included grading the degree of spleen injury by HE staining,locating virus by immunohistochemistry,detecting and analyzing relative expression of DRV,NF-κB,TNF-α,IL-6 through qRT-PCR.The results of HE staining indicated that spleen was swelling and bleeding at 1 day and necrosis at 5days,followed by the formation of“granuloma”structure,and the smaller necrotic lesions was completely mechanized.The result of the immunohistochemistry showed that the DRV mainly appeared in macrophages.The fluorescent quantitation turned out that the relative expression amount of NF-κB and TNF-αboth reached the maximum at 5d.The relative expression amount of IL-6was upregulated from 3dand upregulated significantly at 7d.All of above demonstrated that the virus mainly existed in macrophages and the injury of spleen was positively correlated with the replication of the virus.Cytokines NF-κB,TNF-α,and IL-6expression were up-regulated during the process of infection and then triggered the inflammatory response,which illustrated that NF-κB,TNF-αand IL-6played important roles in spleen injury caused by DRV.