人类巨细胞病毒的变异性分析

Variability analysis of human cytomegalovirus

目的 探讨人巨细胞病毒 (HCMV)基因组的 4个片段在人群和单个病人病程中变异性的临床意义。方法 通过聚合酶链反应 (PCR)对编码糖蛋白B(UL5 5 )、编码DNA单链结合蛋白(UL5 7)、编码主要衣壳蛋白 (UL86 )、编码IE抗原 (UL12 2 ) 4个基因片段进行扩增后 ,用限制性内切酶对扩增片段进行酶切验证 ,再使用HCMV的标准株AD16 9进行试验条件的优化 ,然后对 2 0 0份临床可疑HCMV感染血标本进行检测。结果 2 0 0份血清标本中UL5 5基因PCR阳性率 12 5 % ,酶切阳性率 10 0 % ,与其他 3个基因片段比较差异有显著性 (P <0 0 5 ) ;在 3例HCMV感染持续阳性的病人血清系列标本中UL5 5基因存在阳性转阴性现象。结论 对HCMV进行PCR检测 ,应选择变异性较小的基因片段 ;HCMV通过UL5 5基因的变异可逃避人体免疫系统对其的攻击。

Objective Comparing the variability of four genes of HCMV in the population and the therapy process of single patient.Methods Using PCR to amplify the four genes and restriction enzyme to validate four fragments, These four genes are UL55,UL57,UL86 and UL122 whose coding products are glycoprotein B,single chain binding protein,main capsid protein and IE pp86 separately. Then we use AD169 to optimize the conditions of PCR and restriction enzyme. then we use these conditions to detect 200 blood specimens. Results The PCR positive rate of UL55 is 12.5% and restriction positive rate is 10.0%, which has marked difference with other 3 gene segments(P<0.05). The detection UL55 turned from positive to negative in the series of samples of 3 patient with continuous HCMV infection. Conclusion We should choose fragments with least variability when detecting HCMV with PCR, by using the mutation of UL55 gene, the virus escape the attack of human body immune system.