The impact of antepartum interruption of intrauterine infection on the mutations of precore and core promoter regions of hepatitis B virus / 中华传染病杂志

ABSTRACT

Objective To investigate the impact of injecting hepatitis B immune globulin(HBIG)at third trimester of pregnancy on the nucleotide sequences of precore and basal core promoter(BCP)regions of hepatitis B virus(HBV)DNA.Methods One hundred and twenty pregnant women(67 in HBIG group and 53 in no-HBIG group)were enrolled in this study.Serum HBV DNA level was determined using quantitative real-time polymerase chain reaction(RT-PCR).Relevant serum markers (HBeAg,HBsAg)of HBV were detected by enzyme-linked immunosorbent assay(ELISA).Nucleotide fragments of HBV precore and BCP regions were amplified by nested PCR and then sequenced by automated DNA sequencer.Data were analyzed using t test and chi-square test.Results Sera of 33 women in HBIG group were collected before interruption with HBIG and at delivery.Precore and BCP regions of HBV DNA were amplified and sequenced successfully from double sera of 23 among 33 women. The rates of total nucleotide substitute in precore and BCP regions, that in precore region, and that in BCP region before and after interruption were 1.5% and 1.4%, 0.7% and 0.6%, 1.7% and 1.7%, respectively (Fisher's exact test, X2 =0.627, 0.689, 1.000, respectively,all P＞0.05). The rates of total mutations of hot points including 1896G→A,1899G→A,1762A→T,1764G→A before and after interruption were 27.2% and 13.0%, respectively (x2=5.717, P=0. 017). But the prevalences of these hot points mutations before and after interruption were 30.4%and 17.4%, 17.40/00 and 4.3%, 26.1% and 13.0%, 34.80/00 and 17.4%, respectively, which were all not significantly different (P＞0.05). The rates of nucleotide substitute in precore and BCP regions,that in precore region, and that in BCP region of 53 women in HBIG group and 47 women in no-HBIG group at delivery were 0.9% and 0.8%, 0.3% and 0.3%, 1.1% and 0.9%, respectively (Fisher's exact test, )x2=0.434, 0.839, 0.340, respectively, all P＞0. 05). The rates of total mutations of hot points of women in HBIG group and those in no-HBIG group at delivery were 5.7% and 10.1%,respectively, which was not significantly different (P＞0.05). These hot points mutations including 1896G→A,1899G→A,1762A→T, 1764G→A of women in HBIG group and those in no-HBIG group at delivery were 9.4% and 14.9%, 0 and 2. 1%, 7.5%0 and 10.6%, 5.7% and 12.8%, respectively,which were all not significantly different ( P＞0.05). Conclusions Antepartum interruption of HBV intrauterine infection with HBIG may not raise the nucleotide mutations in precore and BCP regions of HBV DNA. On the other hand, antepartum interruption may decrease mutations of hot points in the precore and BCP regions of HBV DNA.