【摘要】 目的了解深圳市18~25岁抗-HBc阳性合格献血者隐匿性乙肝病毒感染情况,分析血清学和分子生物性特征。方法对HBs Ag(-)、NAT检测无反应性的18~25岁合格献血者血浆进行乙肝两对半检测和抗-HBs定量检测,对抗-HBc阳性标本进行病毒核酸提取和BCP/PC区及S区巢式PCR扩增,对扩增结果阳性产物纯化后进行基因测序及序列分析,同时进行QPCR定量检测。结果在889名18~25岁HBs Ag(-)、NAT检测无反应性的合格献血者中,抗-HBc(+)共231名,占总人数25.98%(231/889),其中18~21岁组70名,占该组19.72%(70/355),22~25岁组161名,占该组30.15%(160/534);抗-HBs(+)共568名,占总人数63.89%(568/889),其中18~21岁组218名,占该组61.41%(218/355),22~25岁组350名,占该组65.54%(350/534);对197例抗-HBc(+)标本利用巢式PCR对HBV S区及BCP/PC区扩增,2例S区阳性,占1.02%(2/197),5例BCP区阳性,占2.54%(5/197),且均属于22~25岁组。对S区阳性PCR产物测序,发现2例均为B型,DNA序列与野生型相比,1例在532号位点由T变异为G,即T532G,氨基酸序列未发生变异。另1例氨基酸序列发生E44U变异。结论经HBs Ag及NAT检测合格的抗-HBc(+)献血者,其血液中仍有一定几率含有HBV DNA,需进一步提高核酸检测方法的灵敏度。更多还原

【Abstract】 Objective To investigate the occult hepatitis B virus infection in anti-HBc positive healthy blood donors and to analyze the serological and biological characteristics of hepatitis B virus in Shengzheng. Methods Qualified volunteer plasma donors aged 18 to 25 who previously tested negative for HBs Ag and nonreactive in NAT were tested for two and a half pairs serum markers( HBs Ag,anti-HBs,HBe Ag,anti-HBe and anti-HBc). The quantity of anti-HBs were detected and determined. The viral nucleic acid from anti-HBc( +) samples were extracted and were amplified by nested PCR at the S and BCP / PC regions. The viral loads of HBV DNA + samples were quantified by QPCR. The resulting PCR products were sequenced and analyzed. Results Among 889 qualified blood donors aged 18 to 25,231 samples were positive for anti-HBc( 25. 98%). Of which,70 belonged to the age group of 18 to 21( 19. 72%) and 161 belonged to the the age group of 22 to 25( 30. 15%). 568 samples were positive for anti-HBs( 63.89%),of which,218 were between ages 18 and 21( 61. 41%),and 350 were between ages 22 and 25( 65. 54%). Using nested PCR to amplify the S and BCP / PC regions of HBV,among197 anti-HBc( +) cases,two cases were classified as S( +),accounting for 1. 02%( 2 /197). Five were classified as BCP / PC( +),accounting for 2. 54%( 5 /197). These cases belonged to the 22 ~ 25 age group. DNA sequence analysis showed that the former two S( +) samples had B genotypes. Comparing the DNA sequence with wild type,one case demonstrated that thymine switched to guanine at position 532 without inducing mutation,while another case E44 U had induced mutation as a result of amino acid variation. Conclusion A low rate of HBV infections still exists in anti-HBc positive healthy blood donors. It is necessary to improve the sensitivity of NAT.更多还原