无血清免疫学标志的乙型肝炎病毒株分子生物学某些特性的初步探讨

Preliminary study on changes of molecular biological characteristics of hepatitis B viruses without serum immunological markers

目的了解无血清免疫学标志的HBV株分子生物学的改变。方法收集104例不明原因性肝炎患者的血清,套式PCR扩增HBV S、X、C基因,HBV S、X区扩增产物测序和变异位点分析。结果检测出隐匿性HBV感染13例。S基因区未发现有义突变,X基因区及重叠核心启动子区、增强子Ⅱ区发现多位点变异。结论X基因区及重叠核心启动子区、增强子Ⅱ区多位点变异可能是无血清免疫学标志HBV株的分子基础。为深入研究隐匿性HBV感染的临床检测及防治奠定基础。

Objective To investigate the molecular biological characteristics changes of hepatitis B viruses without serum immunological marker. Methods One hundred and four patients with liver disease of unknown etiology were enrolled in this study. The S, X and C genes were amplified by a nested polymerase chain reaction（PCR） and the purified PCR products were directly sequenced, the nucleotides and predicted amino acid sequences of S and X gene were analyzed. Results Thirteen cases were confirmed as HBV infection. Sequencing of the amplified fragments showed mutations in the region of X gene and the overlapping core promoter, enhancer Ⅱ. No significant mutations were founded in the region of S gene. Conclusions The molecular mechanism of HBV without serum immunological marker is associated with mutations in X gene and the overlapping core promoter, enhancer Ⅱ. This findings can be used to improve the clinical testing, diagnosis and treatment of occult HBV infection.