慢性HBV感染者低浓度HBsAg相关分子调查研究  

Molecular analysis on chronic hepatitis B patients with low-level HBsAg

作　　者：成军[1] 孙长贵[1] 陈瑜[2] 戴玉柱[1] 许志良[3] 孙关忠[1] 李晓军[4] 

机构地区：[1]解放军第一一七医院临床实验中心,杭州310013 [2]浙江大学医学院附属第一医院检验科 [3]浙江中医药大学附属第一医院检验科 [4]南京军区南京总医院实验诊断科

出　　处：《中华检验医学杂志》2009年第10期1128-1132,共5页Chinese Journal of Laboratory Medicine

基　　金：南京军区医药卫生基金课题项目（02MB018）

摘　　要：目的探讨低浓度HBsAg人群的分子生物学特征及流行病学意义。方法采用PCR及基因测序的方法对HBV慢性感染者136份低浓度HBsAg（低浓度HBsAg组）和44份高浓度HBsAg（高浓度HBsAg组）血清标本进行HBVDNA、酪氨酸-蛋氨酸-天冬氨酸-天冬氨酸（YMDD）变异检测，并分别对浓缩法HBVDNA〉10^5拷贝／L的47份低浓度HBsAg和37份高浓度HBsAg血清标本进行基因型检测，以及对直接法HBVDNA〉10^5拷贝／L的14份低浓度HBsAg和29份高浓度HBsAg血清标本进行S基因序列、血清型进行检测分析，S基因序列采用BioEdit软件与中国株参照序列进行比对。结果低浓度HBsAg组HBVDNA阳性率、YMDD变异率和HBVDNA对数值分别为34．6％（47／136）、0（0／136）和6．5±1．4，高浓度HBsAg组分别为84．1％（37／44）、9．1％（4／44）和8．9±1．8，两组之间差异有统计学意义（浓缩法χ^2=30．8，P〈0．05；直接法χ^2=53．5，P〈0．05；YMDD变异率精确概率法，P=0．003；HBVDNA对数值t=6．5，P〈0．05）；47例低浓度HBsAg病例中分别检出B基因型16例、C基因型5例、未分型26例，14例血清型分别为adw7例、ayw4例、adr2例、ayr1例，在两组人群中基因型的分布差异有统计学意义（χ^2=13．5，P〈0．05），血清型的分布差异无统计学意义（χ^2=4．7，P〉0．05），S基因测序结果未发现S基因变异，但6处16例次存在核苷酸碱基差异而氨基酸同义的多态性特征。结论低浓度HBsAg人群HBVDNA存在低复制现象，基因型、血清型分别以B型、adw／ayw为主，S基因呈多态性特征，低浓度HBsAg存在可能与HBVS基因特殊的分子生物学特征使HBsAg表达低下有关，或与患者感染HBV后机体免疫系统的个体反应导致低浓度HBsAg诱导机体免疫耐受有关。Objective To investigate the molecular characteristics and epidemiological signification of patients with low-level HBsAg. Methods PCR and gene sequencing were used to detect HBV DNA and Tyr-Met-Asp-Asp（YMDD） mutant in 136 serum samples with low-level HBsAg and 44 ser,,m samples with high-level HBsAg. Genotyping was performed in 47 cases with HBV DNA 〉 10^5 copies/L by concentration method and 37 cases with high-level HBsAg. S gene sequences and serotypes were analyzed in 14 cases with HBV DNA 〉 10^5copies/L and 29 cases with higb-level HBsAg. S gene sequences were compared with the consensus sequence of Chinese strain by BioEdit software. Results The HBV DNA-positive rate, YMDD mutation rate and HBV DNA load （logarithm） in low-level and high-level HBsAg group were 34. 6% （47/ 136）, 0% （0/136） , 6. 5 ±1.4 and 84. 1% （37/44）, 9. 1% （4/44）, 8.9 ± 1.8, respectively. There was statistically significant differences between two groups （ for concentration method,χ^2 = 30. 8, P 〈 0. 05 ; for direct method, χ^2 = 53.5, P 〈 0. 05 ; for YMDD mutation ratio, P = 0. 003, For HBV DNA（log） ,t = 6. 5, P 〈 0. 05 ）. The genotypes in low-level HBsAg group included type B（ 16/47 ）, type C （5/47） and non-classified ones （26/47）. There were significant differences between two groups （χ^2= 21.8, P 〈 0. 01 ）. The serotypes included adw （ 7/14 ）, ayw （ 4/14 ）, adr （ 2/14 ） and ayr （ 1/14 ）. There were significant differences in genotypes （χ^2 = 13.5, P 〈 0. 05 ） but not in serotypes between two groups （χ^2= 4. 7, P 〉 0. 05 ）. S gene sequencing results showed no S gene variation was detected, but there were 6 single nucleotide polymorphisms in 16 cases, which would not result in the alternation of amino acid. Conehlsions Low-replication phenomenon of HBV DNA was present in patients with low-level HBsAg. The major genotype and serotype was type B and adw/ayw, respectively. Polymorphic variants have been found in the S gene. The existence of low-l

关 键 词：肝炎 乙型 慢性 肝炎表面抗原 乙型 聚合酶链反应 基因型 

分 类 号：R686[医药卫生—骨科学]