广东阳江地区隐匿性乙型肝炎病毒检出率与分子生物学特性分析

目的调查和分析广东省阳江地区人群的隐匿性乙型肝炎病毒感染(OBI)的检出率与分子生物学特征。方法随机收集广东阳江地区非肝脏性疾病住院患者和健康人群HBsAg阴性血清标本138(人)份,采用巢式聚合酶链反应(Nested-PCR)扩增标本中HBV BCP/PC DNA片段(核苷酸序列区间位nt1679—1973)并测定序列;采用荧光定量聚合酶链反应(QPCR)测定OBI病毒载量。结果在138人(份)HBsAg阴性血清标本中,29份为HBV DNA阳性,确认为OBI,其病毒载量介于不可定量(<1IU/ml)至1008.9IU/ml之间,中位数(M)为8.8IU/ml;抗-HBc阳性健康人群中OBI的检出率名显高于其他HBV血清学标记阳性的标本(P<0.05)。29份OBI标本中有19份的BCP/PC序列出现变异,3份出现缺失,1份出现G1896A/G1899A双位点变异,1份出现G1764A变异;10份标本在CURS和Enh2调控区发生变异。结论阳江地区健康人群的OBI检出率较高,OBI的产生及其低病毒载量存在可能与病毒核心蛋白(C)调控区序列变异相关。

The detection rate and molecular characterization of occult hepatitis B virus infection in Yangjiang area of Guangdong province,China

Objective To investigate the prevalence and molecular characteristics of occult hepatitis B virus infection (OBI) in the populations from Yangjiang area, Guangdong. Methods A total of 138 serum samples were collected randomly from non-hepatopathic patients and healthy people with negative HBsAg in Yangjiang. The BCP/PC (nt1679—1973) fragment was amplified by the nested PCR and then sequenced. Viral loads of OBIs were quantified by QPCR. Results Among the 138 serum samples with origin HBsAg negative, 29 were DNA positive and were identified as OBIs. Viral loads of OBIs ranged between unquantifiable(<1 IU/ml) and 1008.9 IU/ml, with the median(M) of 8.8 IU/ml. The prevalence of OBI was significantly higher in health people than in samples with sero-positive makers(P<0.05). Among 29 OBIs samples,19 mutations, 3 deletions, 1 ntG1896A/G1899A and 1 G1764A were found in BCP/PC region, respectively; 10 mutated in CURS and Enh2 regulatory regions. Conclusion The prevalence of occult HBV infection in health people of Yangjiang was relatively higher than that of other cities. The generation of OBI and the low viral load are supposed to be related with the mutations in regulatory element of core region.