【作者】 严菊英； 卢亦愚； 张健华； 冯燕； 史雯； 茅海燕； 龚黎明； 葛琼； 周敏； 李敏红；

【Author】 YAN Ju-ying,LU Yi-yu,ZHANG Jian-hua, FEN Yan, SHI Wen, MAO Hai-yan (Center for disease control and prevention of Zhejiang Province,Hangzhou 310009 China)

【机构】 浙江省疾病预防控制中心；

【摘要】 目的:研究浙江省1999-2003年麻疹病毒流行株的抗原性变化以及基因特性,阐明其基因特性与麻疹流行的关系,以及抗原性变化对疫苗免疫效果的影响.方法:从麻疹患者含漱液中分离麻疹病毒株,制备大鼠免疫血清,与疫苗株沪191和Edmonston株等进行交叉中和试验,测定各毒株之间抗原比;并采集儿童麻疹疫苗免疫前后血清,分别测定其对不同毒株的中和抗体滴度;采用RT-PCR法扩增麻疹毒株血凝素(H)及核蛋白(N) 基因,进行核苷酸序列测定.结果:浙江99-1和浙江02-2株与沪191株之间的抗原比分别为3.0和7.3;儿童免疫后血清对浙江02-2株的麻疹中和抗体平均几何滴度(GMT)为15.03, 明显低于沪191疫苗株(GMT为68.12);浙江省1999-2003年麻疹流行株之间,H基因氨基酸同源性为99.8%,N基因氨基酸同源性为98.5%-100%;与沪191疫苗株的H基因和N基因相比较,分离株与其在氨基酸水平上同源性分别为95.5%-95.7%和95.9%-96.3%。结论:从基因进化树显示,1999-2003年浙江省分离到的麻疹毒株属于H1基因型,但与疫苗株沪191在抗原性和基因特性上已存在明显的差异,并且对现行麻疹疫苗的免疫效果已形成一定的影响更多还原

【Abstract】 Objective Genetic characteristics and antigenic variation of the wild type measles viruses isolated in Zhejiang Province during 1999 - 2003 were studied in order to elucidate the relationship between genetic characteristics and measles outbreak and to indicate the influence of antigenic variation on measles vaccine effect Method The rats were immunized with the wild type measles virus isolated from the patients and the titer of the antiserum was measured by cross neutralization test with the antigen of the wild type measles virus, vaccine strain of shanghai191 and standard measles virus of Edmonston strain and the antigenic ratios between the strains were calculated. Meanwhile the serum samples collected from the children before and after immunized with the measles vaccine were tested of the titer of neutralizing (NT) antibody responding to the different measles strains. In addition, the N and H genes of measles virus were amplified by reverse transcription polymerase chain reaction (RT-PCR) and sequenced. Result Antigenic ratios of Zhejiang99-1 and Zhejiang02-2 to shanghai191 strain were 3.0 and 7.3 respectively; The geometric mean titer (GMT) of the NT antibody from the primary-vaccinated individuals to Zhejaing02-2 strain was 15.03 which was obviously lower than to the shanghai191 vaccine (GMT was 68.12); Besides, the identity of the amino acide sequence of HA protein and N protein was 99.8% and 98.5%-100% respectively between the wild type measles virus circulating during 1999-2003 in Zhejiang Province. Compare with china vaccine strain(shanghai191), the isolates had homogeneties of 95.5% - 95.7%. and 95.9% - 96.3% on H and N proteins respectively. Conclusion The measles isolates were all genotype H1 analysed by the phylogenic trees of H and N gene; it was obviously different from Shanghai191 strain which had influenced partily immunoprotective effect of current measles vaccine.更多还原