摘要
为探讨乙型肝炎病毒（ＨＢＶ）感染血清学不典型表现的分子病毒学基础，用聚合酶链反应（ＰＣＲ）产物直接序列分析测定中国人感染的ＨＢＶＳ基因核背酸序列。结果发现：１５例ＨＢｓＡｇ阴性ＨＢＶ感染者中，１例第５５２位碱基胸腺嘧啶（Ｔ）被胞嘧啶（Ｃ）替换，导致ＨＢｓＡｇ第１３３位蛋氨酸被苏氨酸替代；３例第５４６位碱基Ｃ被Ｔ替换，导致ＨＢｓＡｇ第１３１位苏氨酸异亮氨酸替代；３例“Ａ”决定簇前密码子１２２～１２４间氨基酸插入。１例ＨＢｓＡｇ／抗ＨＢｓ共存个例可见ＨＢＶ第５８７位碱基鸟嘌呤（Ｇ）被腺嘌呤（Ａ）替换，导致ＨＢｓＡｇ第１４５位甘氨酸被精氨酸替代。结果说明ＨＢＶ感染血清学的不典型可能与感染ＨＢＶＳ基因插入和点突变变异株有关。研究同时提示：在中国这一ＨＢＶ感染高发区，血清学诊断的所谓的“非甲～戊”型肝炎中至少有部分病人为感染了ＨＢＶ变异株所致。
Serological and virological studies have been done to identify the envelope variant in subjects with or without detectable hepatitis B surface antigen(HBsAg).Two types of envelope vasriants of hepatitis B virus (HBV) were identified in HBsAg negative but HBV DNA positive carriers compared with HBsAg positive patients with chronic liver diseases.Amino acid substitutions in the immunodominant epitope region of the 'A' determinant could be detected in 5 cases of carriers.Presence of a isoleucine instead of threonine at position 131 was seen in consensus sequences from the Chinese isolates in 3 cases of paid blood donors.A substitution of a methionine to threonine was detected in one patient with chronic liver disease.In a vaccinated child,codon 145 variant was seen as described previously.The isolates from 3 cases of HBsAg negative patients are insertion mutants:additional aminoacids are inserted in the envelope gene of HBV.This study suggests that the envelope variants of HBV might be responsible for some cases of socalled non A E hepatitis serologically identified.
出处
《解放军医学杂志》
CAS
CSCD
北大核心
1996年第4期246-248,共3页
Medical Journal of Chinese People's Liberation Army
基金
国家和广东省自然科学基金
