福州市柯萨奇病毒A10型VP1区基因特征分析

Gene characteristics analysis for VP1 region of coxsackie A10 in Fuzhou

目的了解福州地区流行的柯萨奇病毒A10型（CV-A10）的VP1区基因特征及种系进化分布。方法采集临床诊断为手足口病患者的咽拭子或肛拭子样本，通过real—time PCR法确定样本的肠道病毒型别。选取部分CV—A10的临床样本，利用RD细胞进行病毒分离，RT—PCR扩增肠道病毒的VPl基因片段，并进行序列测定，利用DNAStar和MEGA5.1软件进行核苷酸和氨基酸同源性分析并构建亲缘进化树。结果检测出的1951份肠道病毒阳性样本中，肠道病毒71型（EV-A71）、柯萨奇病毒A16型（CV-A16）、CV-A10的阳性率分别为24．1％，16．7％，9．4％，不同肠道病毒阳性率差异有统计学意义。福州市CV-A10型各分离株的核苷酸和氨基酸同源性分别为94．0％～99．9％和97．7％～100．0％，与CV—A10原型株（Kowalik株）的同源性分别为76．4％～76．7％和91．9％～93．3％。亲缘进化树的分析结果显示福州地区CV-A10分离株属于D亚型。结论CV-A10是引起福州地区手足口病的常见病原体之一，本次分离到的CV—A10病毒株均属于D基因型。

Objective To understand the variation characteristics of VP1 gene and evolutionary distribution of the coxsackie A10 virus in Fuzhou. Methods The throat or anal swabs were collected from suspected hand- foot-mouth disease （HFMD） patients. Real-time PCR was used to identified the enterovirus types for all speci- mens. Viruses were isolated with RD cells. VP1 genes of coxsackie A10 viruses were amplified by RT- PCR. Then, nucleotide sequences were analyzed and amino acid sequences were deduced. The phylogenetic tree was constructed with MEGA 5.1 and DNASTAR MegAlign software. Results A total of 1 951 positive samples were detected where the positive rates of EV71, coxsackie A16 and Coxsackie At0 were 24.1%, 16.7%, 9.4%, respectively. Positive difference of different intestinal virus was statistically significant. The homology of nucleotide and amino acid among the CV-A10 isolated strains were 94.0%-99.9%, 7.7%- 100.0%, respectively, compared with the CV-A10 prototype strain （Kowalik strain） the homology of nucleo- tide and amino acid was 76.4%-76.7% and 91.9%-93.3% respectively. Phylogenetic tree showed that CV- A10 isolated strains were most similar to the type D. Conclusions Coxsackie A10 were the major pathogens of HFMD in Fuzhou. Evolution analysis showed that the CoxA10 strains isolated in Fuzhou got together into a cluster genotype D.