禽冠状病毒组织嗜性和固有免疫应答差异研究  

Study on the Differences in Tissue Tropism and Innate Immune Response with different Avian Coronavirus strains

作　　者：李雪妍 徐双[1] 朱瑾彦 阮文科[1] LI Xueyan;XU Shuang;ZHU Jinyan;RUAN Wenke(Animal Science and Technology College,Beijing Unirversity of Agriculture,Beijing,102206,China)

机构地区：[1]北京农学院动物科技学院,北京102206

出　　处：《病毒学报》2021年第3期658-666,共9页Chinese Journal of Virology

基　　金：国家自然科学基金(项目号:31572499)。

摘　　要：鸡传染性支气管炎(Infectious Bronchitis,IB)一直是危害世界养禽业的最重要的疫病之一。IBV变异频繁,导致出现多种不同致病性毒株,不同致病性IBV的出现可能与其感染后免疫系统的激活有关。对IBV组织嗜性和感染后的免疫机制的研究对疫病防控具有重要意义。本研究为了探究IBV不同毒株组织嗜性和固有免疫应答之间的关系。将不同IBV毒株接种原代细胞、鸡胚、SPF鸡,进行各器官的组织嗜性鉴定,应用荧光定量的方法测定TLR3、TLR7、MAVS、MDA5、IFN-β和IFN-γ等细胞因子在SPF鸡的不同组织器官包括气管、肾、胃、肺、脾和法氏囊中mRNA的表达差异。结果表明,除H52为已知疫苗毒株外,AH毒株对泌尿系统致病性强,TM毒株对消化系统有致病性。感染实验后显示,在气管中,AH感染组MDA5的mRNA表达显著下调,TM组IFN-β和IFN-γ的mRNA表达显著性上调,H52组MAVS与IFN-β表达上调;在肺脏中,AH组TLR3、TLR7、IFN-β和IFN-γ显著性上调,在TM组能看到MDA5和IFN-γ表达显著升高,H52组的TLR3、TLR7、MDA5、IFN-β和IFN-γ上调;在肾中,AH组和TM组IFNβ和TLR7表达下调,H52组TLR7、MAVS、IFN-β和IFN-γ表达上调;在腺胃中,AH组TLR7、MAVS、MDA5、IFN-β和IFN-γ表达上调,TM株IFN-γ表达上调,H52组TLR7表达显著性下调,MAVS、IFN-β和IFN-γ表达上调;在脾脏中,AH组MAVS表达上调,TM组TLR3、TLR7和MDA5表达显著性上调。H52组TLR7和IFN-γ的表达也显著提高;在法氏囊中,AH组各因子表达无显著性差异,TM组TLR7、MDA5和IFN-γ表达上调,H52组中TLR3、TLR7、MAVS、MDA5、IFN-β和IFN-γ表达均显著上调。不同组织嗜性的IBV毒株在各组织器官中各细胞因子表达量不同,不同组织嗜性毒株在固有免疫应答上存在差异且与免疫分子表达水平有相关性。本实验为不同IBV毒株感染机制、疫苗开发、病原与细胞相互作用的研究应用奠定理论基础。Infectious bronchitis(IB)has been one of the most important diseases that endanger the world’s poultry industry.Frequent mutations of IBV lead to the emergence of many different pathogenic strains.The appearance of different pathogenic IBV strains may be related to the activation of the immune system after infection.The study on IBV tissue tropism and the immune mechanism after infection is of great significance to the prevention and control of epidemic diseases.The purpose of this study is to investigate the relationship between the tissue tropism and innate immune responses of different strains of chicken infectious bronchitis virus(IB)in avian coronavirus.Different IBV strains were inoculated into primary cells,chicken embryos,and SPF chickens to identify the tissue tropism to each organ.TLR3,TLR7,MAVS,MDA5,IFN-β,and IFN-γand other cytokines were measured by fluorescence quantitative methods to find out different expressions of mRNA in different tissues and organs of SPF chicken including trachea,kidney,stomach,lung,spleen and bursa.The results showed that besides H52,a known vaccine strain,the AH strain is highly pathogenic to the urinary system and the TM strain is pathogenic to the digestive system.The infection experiment showed that in trachea,the mRNA expression of MDA5 in AH infection group was significantly down-regulated,the mRNA expression of IFN-βand IFN-γin TM group was significantly up-regulated,and the expression of MAVS and IFN-βin H52 group was up-regulated.In lung tissues,TLR3,TLR7,IFN-β,and IFN-γwere significantly upregulated in AH group.MDA5 and IFN-γexpressions were significantly increased in the TM group,and TLR3,TLR7,MDA5,IFN-βand IFN-γwere up-regulated in the H52 group.In the kidney,the expressions of IFNβand TLR7 were down-regulated in AH and TM groups,and the expressions of TLR7,MAVS,IFN-β,and IFN-γwere up-regulated in the H52 group.In the glandular stomach,TLR7,MAVS,MDA5,IFN-β,and IFN-γexpression were up-regulated in AH group,TM strain IFN-γexpression was up-regulate

关 键 词：禽冠状病毒IBV 组织嗜性 固有免疫应答 细胞因子 

分 类 号：S855.3[农业科学—临床兽医学]