Variability of NS1 proteins among H9N2 avian influenza viruses isolated in Israel during 2000–2009
Variability of NS1 proteins among H9N2 avian influenza viruses isolated in Israel during 2000–2009
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DOI：
10.1007/s11262-010-0522-3
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发表时间：
2010-08
期刊：
影响因子：
1.6
通讯作者：
A. Panshin;N. Golender;Irit Davidson;S. Nagar;M. Garsia;M. Jackwood;E. Mundt;A. Alturi;S. Perk
中科院分区：
文献类型：
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作者：
A. Panshin;N. Golender;Irit Davidson;S. Nagar;M. Garsia;M. Jackwood;E. Mundt;A. Alturi;S. Perk
本研究的主要目的是表征以色列分离的H9 N2禽流感病毒（AIV）的NS 1蛋白，并探讨使用基于NS 1的间接ELISA的可能性。为了实现这些目的，对2000-2009年在以色列分离的79株H9 N2亚型禽流感病毒的非结构基因（NS 1）进行了测序和遗传分析。系统发育分析表明，在此期间，以色列发生了四次不同的H9 N2传入。NS 1蛋白质的推断氨基酸序列的分析显示，第3和第4次引入的病毒之间存在约10%的高差异。以重组NS 1蛋白为抗原，用间接ELISA法检测免疫血清中的抗体。从实验感染H9 N2的鸡在感染后4、7、10、14和21天获得免疫血清。用酶联免疫吸附试验（NS 1-ELISA）检测到所有实验感染第3次或第4次引入AIV的鸡的血清含有抗NS 1抗体，即使用作NS 1-ELISA抗原的重组NS 1在其氨基酸序列上与引起实验鸟感染的AIV的NS 1蛋白显著不同。这些发现表明，属于第3次和第4次引入的病毒在抗原表位位置之外的NS 1蛋白的位点是基于NS 1的iELISA结果的原因。
The main aims of the present study were to characterize NS1 protein from H9N2 avian influenza viruses (AIVs) isolated in Israel and to investigate the possibility to use NS1-based indirect ELISA. To achieve these purposes, the non-structural gene (NS1) of 79 AIVs of the H9N2 subtype isolated in Israel in 2000–2009 was sequenced and genetically analyzed. The phylogenetic analysis demonstrated that four distinct introductions of H9N2 occurred in Israel during this period. Analysis of the inferred amino acid sequences of the NS1 proteins showed high, about 10%, differences between viruses of the 3rd and 4th introductions. Antibodies against NS1 protein in immune sera were tested by means of indirect ELISA using recombinant NS1 as antigen. Immune sera were obtained from experimentally H9N2-infected chicken after infection on 4, 7, 10, 14, and 21 days. All sera from chickens experimentally infected with 3rd- or 4th-introduction AIV contained anti-NS1 antibodies that were detected by enzyme-linked immunosorbent assay (NS1-ELISA) even though the recombinant NS1 used as antigen for NS1-ELISA differed significantly in its amino acid sequences from the NS1 protein of AIV that caused infection in experimental birds. These findings indicate that the sites of the NS1 protein by which viruses belonging to 3rd and 4th introduction are out of antigenic epitope positions were responsible for the results of NS1-based iELISA.