婴儿人巨细胞病毒感染的不同临床表现与糖蛋白B基因型关系的研究

Association between clinical manifestations of infants with human cytomegalovirus infection and glycoprotein B genotype

目的研究婴儿人巨细胞病毒(HCMV)感染的不同临床表现与巨细胞病毒糖蛋白 B(gB)基因型的关系。方法 HCMV 感染且有临床症状的婴儿107例,无临床症状的婴儿25例,用套式 PCR 法扩增 gB 基因片段,限制性片段长度多态性分析(RFLP)对 gB 基因进行分型,并对部分标本通过测序进行验证。结果在有临床症状的107例婴儿中,检出 gB Ⅰ型53例,gBⅡ型20例,gBⅢ型18例,gB Ⅰ、Ⅱ混合型7例,gB Ⅰ、Ⅲ混合型5例,gBⅡ、Ⅲ混合型4例,未发现 gB Ⅳ型。其中有肝功能损害的53例婴儿中检出 gB Ⅰ型36例,gBⅡ型5例,gB Ⅲ型7例,gB Ⅰ、Ⅱ混合型3例,gBⅠ、Ⅲ混合型2例,gB Ⅰ型明显占多数(P<0.05)。在无临床症状的25例婴儿中检出 gB Ⅰ型10例,gBⅡ型6例,gBⅢ型8例,gB Ⅰ、Ⅱ混合型1例。对132例婴儿中的24例标本进行测序,结果与相应的典型菌株序列比较,相似性为97.06%～99.64%。结论 RFLP 对 HCMV 的 gB 基因分型明确可靠。有肝功能损害的 HCMV 感染婴儿,gB Ⅰ型为优势基因型。

Objective To investigate the association between the clinical manifestations of infants with human cytomegalovirus （HCMV） infection and glycoprotein B （gB） genotype. Methods Urine samples were obtained from 107 symptomatic infants with HCMV infection confirmed by flurescence quantitative PCR, 70 male and 37 female, aged 5 d-8 months, and 25 asymptomatic infants with HCMV infection, 16 male and 9 female, aged 21 d-7 months. A fragment of glycoprotein B gene was amplified by nested PCR （nPCR）. HCMV gB genotyping was carried out by restriction fragment length polymorphism （RFLP）, and some of the amplified DNA fragments were verified by DNA sequencing. Results Of the HCMV specimens from 107 infants, 53 were typed as gB group Ⅰ , 20 as gB Ⅱ, 18 as gBⅢ, 7 as gB Ⅰ and gB Ⅱ, 5 as gB Ⅰ and gBⅢ, and 4 as gB Ⅱ and gBⅢ, and gB Ⅳ was not found. The HCMV gB genotype from 53 infants with hepatic function damage showed that 36 were classified as gB Ⅰ , 5 as gB Ⅱ , 7 as gB Ⅲ, 3 as gB Ⅰ and gB Ⅱ , and 2 as gB Ⅰ and gBⅢ. The gB Ⅰ genotype was more common among the infants with hepatic function damage （ P 〈 0.05 ）. The distribution of gB genotype in the asymptomatic infants was as follow： gB Ⅰ, 10/25; gBⅡ, 6/25; gBⅢ, 8/25; and gB Ⅰ and gBⅡ, 1/25. The homology of PCR products of HCMV gB in 24 strains amplified compared with the sequences of prototype strains in GenBank was from 97.06% to 99.64%. Conclusion RFLP analysis of HCMV gB genotype is definite and reliable. The gB Ⅰ genotype is more common among the infants with hepatic function damage.