乙型肝炎病毒转录体血清学检测及其在母婴垂直传播中的意义

Serodetection of hepatitis B virus transcripts and its significance in vertical transmission

目的:探讨乙型肝炎病毒(hepatitisBvirus,HBV)转录体的检测在母婴传播中的意义.方法:自HBV表面抗原(HBsAg)阳性母亲及其新生儿血清中提取核酸,经PCR及RTPCR扩增HBVDNA,全长型RNA(FulllengthRNA,fRNA)和顿挫型RNA(TruncatedRNA,trRNA),琼脂糖凝胶电泳显示产物.结果:HBeAg(+)/HBeAg(-)母亲血样病毒DNA,fRNA和trRNA的阳性率分别为75%,65%,70%和37.5%,20.8%,58.3%,两组间前两项指标相差显著.44例新生儿血样HBsAg,病毒DNA和fRNA阳性率分别为9.1%,4.5%和6.8%,显著低于其母亲;儿血中trRNA阳性率达52.3%,与其母亲trRNA的存在有一定关联.15例乙肝五项检测仅显示HBsAb阳性的新生儿血样中均未见到病毒DNA和fRNA,但其中11例(73.3%)可检测到trRNA.结论:与HBsAg、病毒DNA及fRNA相比,trRNA可能是HBV母婴传播过程中早期出现的血清学指标,这一指标的应用可能有助于更精确的确定新生儿HBV感染的状态.

AIM: To investigate the significance of viral transcripts in HBV vertical transmission through serodetection.METHODS: Viral nucleic acids were extracted from sera of the HBV surface antigen positive mothers and of their newborn infants. HBV DNA and RNAs, including the full-length and truncated RNA molecules, were amplified respectively through PCR and RT-PCR targeted to the HBV X protein-encoding region. RESULTS: The viral DNA, fRNA and trRNA were detected in HBeAg(+)/ HBeAg(-)mothers at frequencies of 75%, 65%, 70% and 37.5%, 20.8%, 58.3%, respectively. The differences between these two groups were significant for the former two parameters. HBsAg,viral DNA and fRNA were detected in much less infant samples, respectively at frequencies of 9.1%,4.5% and 6.8%. Strikingly, trRNA was detected in 23 samples (52.3%), whose occurrence appearing correlative to the presence of the RNA element in the sera of the mothers. A signal for trRNA was also observed in 11 of the 15 (73.3%) infant samples in which immune seroassays only revealed presence of anti-HBsAg antibodies. CONCLUSION: Compared with HBsAg, viral DNA and fRNA, trRNA appears early in the blood circulation of most infected infants, thereby being likely to be a sensitive marker for the identification of the vertical transmission of HBV. Its application is helpful for a better understanding of the HBV expression profiles in the infected infants.