为深入了解我国H5亚型高致病性禽流感病毒的抗原性变异情况及其规律，对我国2012—2015年分离的H5亚型高致病性禽流感病毒进行了HA基因的扩增、测序与遗传进化分析。结果发现这些流行毒株主要分布在第2.3.2.1分支、第2.3.4.4分支和第7.2分支。制备流行毒株的单因子阳性血清，与相应疫苗株进行交叉血凝抑制试验，计算抗原相关系数，并对各分支流行毒与相应疫苗之间的HA1主要抗原位点差异进行分析。结果表明，Re-4、Re-5、Re-6、Re-7、Re-8疫苗株之间的血凝抑制抗原相关系数在0.17~0.67之间，表明不同分支之间的抗原性有较大差异。随着时间的推移，分支内流行毒与疫苗之间的血凝抑制抗原相关性差异会越来越大，抗原性变异程度增加，这与HA1主要抗原位点差异分析的结果一致。因此，要取得理想的防控效果，必须及时更新疫苗，使用与流行毒匹配性更好的疫苗。这些数据为深入了解H5亚型高致病性禽流感病毒的抗原变异和对该病毒的防控提供了技术支持。%To further understand the situation of antigenic variation of H5 subtype highly pathogenic avian influenza viruses and its regularity,in this paper,the HA genes of H5 subtype highly pathogenic avian influenza viruses isolated from 2012 to 2015 were amplified,sequenced and analyzed with genetic evolution. It was showed that the epidemic strains were mainly distributed into the clades 2.3.2.1,7.2,and 2.3.4.4. The single factor positive sera against pan-demic strains were prepared and cross hemagglutination inhibition tests were done with standard positive sera against corresponding vaccines. The relativity of antigen index was calculated and the differences of major antigen sites in HA1 genes between popular strains and corresponding vaccine strains were analyzed. The results showed that the relativity of hemagglutination inhibition antigen index of Re-4,Re-5,Re-6,Re-7,Re-8 was between 0.17~0.67,indicated that the antigenicities between the different clades had big differences. With the passage of time,the relativity of hemag-glutination inhibition antigen between popular strains and vaccine strains in one clade will be more and more low,the degree of antigenic variation will increase. It was consistent with the results of variance analysis of the main antigen sites in HA1 region. In order to obtain ideal control effect,vaccines must be updated timely,so as to make them are more married with popular strains. These data will provide technical support for understanding the antigenic variation and the prevention and control of this virus.
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