鸡传染性支气管炎病毒Jin13株的分离与鉴定

为了对近年从郑州郊区鸡群中分离到的1株传染性支气管炎病毒(Jin13株)进行定型鉴定,作者采用气管环(TOC)中和试验、血凝抑制(HI)试验、单抗交叉ELISA、序列分析和免疫试验对其进行了研究。气管环(TOC)中和试验和血凝抑制(HI)试验表明Jin13病毒只与M41阳性血清反应,而与其它ND、EDS76、H9AI、IBD标准阳性血清不发生反应,序列分析证实该分离毒Jin13株是IBV。在交叉气管环(TOC)中和试验和交叉血凝抑制(HI)试验中Jin13株与肾变型Y株不交叉(R≤0.25),而与马萨株血清型的M41株和H52株有明显交叉(0.25≤R≤0.8);单抗交叉ELISA结果显示Jin13株与针对M41株的J1单抗有很好的反应(≥640～1 280),而与针对肾变型Y株的单抗C2几乎不反应(≤40),这进一步证实了Jin13与呼吸型M41株、H52株属同一血清型。与M41株相比较,Jin13株S1氨基酸序列在第126,386,390,461位出现了突变,又在S1基因第1 166位出现一个新Aiu I酶切位点,是M41株的一个变异株。对Jin13株纯化后原代毒进行免疫效力检测证实其免疫原性优于M41株和H52株。Jin13毒株是一株免疫原性良好的IBV地方流行毒株。

Isolation and identification of the endemic strain Jin13 of avian infectious bronchitis virus

This experiment was conducted to study serotype identification of the endemic strain of avian in-fectious bronchitis virus,Jin13,isolated recently from the infected chicken flocks in the suburbs of Zhengzhou city.Trachea organ cultures(TOC)neutralization,hemagglutination inhibition(HI),cross-ELISA based on the monoclonal antibody,sequencing,and immunization test were adopted in this study.Jin13 strain could react to the sera against M41 virus but not to the standard positive serum against NDV,EDS-76V,H9 AIV and IBDV in TOC and HI test,and sequence analysis confirmed that Jin13 strain virus is avian infectious bronchitis virus.Jin13 strain showed significant cross-reaction to the Massachusetts serotype M41 strain and H52 strain(0.25≤R≤0.8),but not to the nephropathogenic strain Y(R≤0.25) in TOC and cross-HI test.The results of cross-ELISA based on the monoclonal antibody indicated Jin13 strain had a significant response to J1 monoclonal antibody to M41 virus strain(≥640~1280) but not to the C2 monoclonal antibody to Y virus strain(≤40).These results further con-firmed that Jin13 and respiratory-type M41 strain,H52 strain are the same serotype IBV.Compared with the M41 strain,S1 amino acid sequence of Jin13 strain had emergence of mutations in the sites 126,386,390,and 461.Moreover,a new restriction site,AIu I,occurred in the 1 166 site of the Jin13 strain S1 gene.These results sug-gested that Jin13 strain is a mutant strain of M41 IBV.Immunization test confirmed that immunogenicity of Jin13 was superior to that of M41 and H52 strain.Jin13 strain is an endemic strain of IBV with good immunogenicity.