乙型病毒性肝炎隐匿性感染与S基因氨基酸变异的研究

Study on occult hepatitis B infection and S gene amino acid mutation

目的了解新疆中小学生中乙型病毒性肝炎(HB)病毒(HBV)表面抗原(HBs Ag)阴性而HBV核酸(HBV DNA)阳性的隐匿性HBV的感染情况及S基因氨基酸变异。方法采用整群抽样的方法对新疆4所中小学校的学生进行检测,对HBs Ag阴性样本进行HBV DNA提取和S基因扩增,对扩增阳性的样本进行测序;采用分子遗传学分析(MEGA 5.0)软件对测得序列进行基因序列分析。结果 413例HBs Ag阴性样本中,33例在S基因测序中呈现阳性,其中9例学生S基因的亲水区(MHR)氨基酸发生了变异,分别发生7次T143S,5次I110L,5次S113T,5次T126I,3次K122R,3次K160R,2次F134Y和2次K159G。26例B基因型样本中有1例样本为ayw2血清型,其余25例均为adw2血清型。5例C基因型样本均为adrq+血清型。2例D基因型样本均为ayw2血清型。结论 HBs Ag阴性的学生血液中存在HBV隐匿性感染,S基因存在氨基酸突变,需重视HBV隐匿性感染的发生和发展。

[Objective]To investigate the occult hepatitis B virus infection （OBI） among primary and middle school students in Xinjiang, which the diagnostic criteria is negative HBsAg with positive HBV DNA, explore the S gene amino acid mutation at the same time.[Methods]The students were collected from 4 primary and middle schools in Xinjiang by cluster sampling. HBV DNA extraction and S gene amplification were conducted in the samples with negative HBsAg, and the genome sequencing was performed in positive amplification samples. The MEGA 5.0 software was used to analyze the gene sequence.[Results]Among 413 negative HBsAg samples, 33 cases were positive in the S gene sequencing. The MHR mutation of S gene amino acid were observed in 9 students, including seven T143S, five Ill0L, five Sll3T,five T126I, three K122R, three K160R, two F134Y and two KI59G. There was 1 ease of serotype ayw2 in 26 cases of genotype B, and rest 25 cases were serotype adw2. All of 5 genotype C cases were serotype adrq＋. Both 2 genotype D cases were serotype ayw2.[Conclusion]The HBV infection has been observed in students with negative HBsAg, and there are the S gene amino acid mutations. So it is neeessary to pay attention to OBI.