母婴传播后母子体内乙型肝炎病毒前S/S基因变异研究  

PreS/S gene mutations in HBV in children infected through mother-to-infant transmission and in their mothers

作　　者：许红梅[1] 彭明利[1] 凌宁[1] 卿玉玲[1] 任红[1] 

机构地区：[1]重庆医科大学病毒性肝炎研究所,400010

出　　处：《中华肝脏病杂志》2003年第7期398-401,共4页Chinese Journal of Hepatology

基　　金：国家自然科学基金(396-30280)

摘　　要：目的 通过经母婴传播获得乙型肝炎病毒(HBV)感染的慢性无症状乙型肝炎表面抗原携带者(ASC)母子体内HBV PreS/S基因序列研究,了解来源相同的HBV在不同程度病毒血症情况下PreS/S基因变异的特点。方法 选择15对母孕前为HBV感染、未接种过乙型肝炎疫苗且均未使用过抗HBV药物的ASC母子。应用T-A克隆技术构建重组质粒pGEM-PreS/S、双酶切进行鉴定,每个患者选2个酶切鉴定正确的克隆测序并进行分析。结果 选择15对ASC母子,根据HBV病毒血症高低分为3组,每组5对,A组母子均为高病毒血症,B组子女为高病毒血症、母亲为低病毒血症,C组子女为低病毒血症、母亲为高病毒血症。高病毒血症患者均为乙型肝炎e抗原(+),低病毒血症均为抗-HBe(+)。母子HBV亚型相同,各组中有4/5对母子为B/adw2、1/5对母子为C/adrq+亚型。对每组中B/adw2亚型HBV患者的PreS/S基因进行分析显示:高病毒血症组间或低病毒血症组间HBV PreS/S基因变异数目及位点差异均无显著性,变异与年龄无关,低病毒血症患者变异数目及位点明显高于高病毒血症患者。两个低病毒血症组PreS/S基因绝大多数变异位点相同(113个),其中变异热点85个、可引起37个氨基酸变异,这些变异的氨基酸大多位于免疫表位内或(和)其附近。结论 HBV变异可能与感染的时间长短无关;Objective To investigate the characteristics of mutations in PreS/S gene of HBV in children infected through mother-to-infant transmission and in their mothers with different degree of viremia. Methods There were 15 pairs of child and mother in this study. Mothers of all children were chronic asymptomatic HBsAg carrier (ASC) before pregnancy and the children were not inoculated against HBV after birth. Anti-HBV medicine was never administrated to all subjects. The serological markers of hepatitis A, B, C, D and E virus were tested and the liters of serum HBV DNA were quantitated. PreS/S gene was amplified by PCR and cloned into pGEM-T vector with T-A cloning technique. The recombinant plasmid pGEM- PreS/S was confirmed by digestion with restriction enzyme Apa I and Sac I . Two clones were selected to be sequenced from each patient. Results According to the degree of viremia in every pair of mother and child, 15 pairs of child and mother were divided into three groups: group A (both children and mothers had high viremia with HBeAg-positive), group B (high in children and low in mothers with anti-HBe positive), and group C (low in children and high in mothers), and there were 5 pairs in each group. The subtype of each pair was the same. There were 4/5 pairs of HBV with B/adw2 and 1/5 pair of HBV with C/adrq+ in each group. It was shown that there were no difference among the four high viremia groups or between the two low viremia groups in the number of mutations and the number of mutational positions. However, there was significant difference between high viremia group and low viremia group. The mutation was not related to age. There were 56 mutational positions and there was no mutational hotspot in high viremia patients. In two low viremia groups (the mothers in group B and the children in group C), there were 113 mutational positions and 85 mutational positions were hotspots (owned by 5/8 clones in each) which could make 37 amino acids changed. Most of mutational amino acids were located within T and B cell epi

关 键 词：母婴传播 母子体 乙型肝炎病毒 S/S基因变异 HBV 疫苗 

分 类 号：R512.62[医药卫生—内科学]