HBeAg阳性慢性乙型肝炎患者HBV前C/BCP突变/准种与HBeAg和HBV DNA的关系

Relationship between HBV pre-C/BCP mutation/quasispecies and HBeAg and HBV DNA in HBeAg positive patients with chronic hepatitis B

目的探讨HBeAg阳性慢性乙型肝炎(eP-CHB)HBV前C/BCP突变/准种及其与HBeAg、HBV DNA水平的关系。方法采用断面研究对2016年1月至2018年12月就诊于首都医科大学附属北京佑安医院的220例eP-CHB患者进行前C/BCP突变检测,其中24例患者进行前C/BCP区扩增、克隆,同步检测血清HBeAg和HBV DNA水平,分析前C/BCP突变/准种的发生情况及其与HBeAg和HBV DNA水平的关系。结果220例eP-CHB患者中,HBV前C/BCP总突变率为70.0%(154/220),前C/BCP共同突变率为18.2%(40/220),前C突变率为30.9%(68/220),BCP突变率为57.3%(126/220)。HBV DNA≥5 lgIU/ml患者上述4种突变检出率均高于HBV DNA<5 lgIU/ml者,其中前C/BCP总突变和BCP突变患者差异有统计学意义(χ^2=5.809、P=0.016,χ^2=5.081、P=0.024)。HBeAg水平越低(<500 COI、500~1000 COI和>1000 COI共3组患者比较),以上4种突变检出率越高,差异有统计学意义(χ^2=31.738、17.291、16.263、22.164,P均<0.001)。HBV DNA≥5 lgIU/ml患者中,HBeAg水平越低,以上4种突变检出率越高,差异亦均有统计学意义(χ^2=40.503、19.654、16.727、29.119,P<0.001)。准种检测中,前C区高突变组患者HBeAg水平低于低突变组,差异有统计学意义(t=2.230、P=0.017),前C、BCP高突变组与低突变组间HBV DNA水平差异无统计学意义(t=0.624、P=0.462,t=0.893、P=0.317)。结论eP-CHB患者中仍存在广泛的前C/BCP突变。高HBV DNA、低HBeAg表达者,前C和BCP突变的发生率较高;前C区突变株在准种中比率高者更影响HBeAg的表达。推测前C/BCP突变可能是eP-CHB出现低HBeAg、高HBV DNA,并导致抗病毒治疗停药后易复发的原因。

Objective To investigate the pre-C/BCP mutation and quasispecies in patients with hepatitis B virus e antigen(HBeAg)positive(eP-CHB)and the relationship with the levels of HBeAg and HBV DNA.Methods The pre-C/BCP mutation was detected in 220 patients with eP-CHB from January 2016 to December 2018 admitted in Beijing You’an Hospital,Capital Medical University by cross-sectional study.Among whom,the pre-C/BCP region in 24 patients was amplified and cloned.Serum HBeAg and HBV DNA levels were detected simultaneously.The pre-C/BCP mutation and quasispecies and the relationship with HBeAg and HBV DNA levels were analyzed,respectively.Results Among the 220 patients with eP-CHB,total mutation rate of pre-C/BCP was 70.0%(154/220),co-mutation rate of pre-C/BCP was 18.2%(40/220)and mutation rate of pre-C and BCP were 30.9%(68/220)and 57.3%(126/220),respectively.The detection rates of the above four mutations in patients with HBV DNA≥5 lgIU/ml were all higher than those of patients with HBV DNA<5 lgIU/ml,the rates of BCP mutation and pre-C/BCP total mutation were significantly different(χ^2=5.809,P=0.016;χ^2=5.081,P=0.024).The lower HBeAg level was(<500 COI,500-1000 COI and>1000 COI),the higher detection rates of the above four mutations were,all with significant difference(χ^2=31.738,17.291,16.263,22.164;all P<0.001).Similarly,among the cases with HBV DNA≥5 lgIU/ml,the detection rates of the above four mutations were higher among the cases with lower HBeAg level,with significant differences(χ^2=40.503,19.654,16.727,29.119;all P<0.001).In quasispecies detection,HBeAg level of cases with high mutation of the pre-C region was lower than that with low mutation,with significant difference(t=2.230,P=0.017).There was no significant difference between HBV DNA levels of cases with high mutation and low mutation of the pre-C region(t=0.624,P=0.462)and BCP(t=0.893,P=0.317).Conclusions There were still extensive pre-C/BCP mutations in eP-CHB.The mutation rates of pre-C and BCP were higher in patients with high HBV DNA and low HBeAg level.The high proportion of pre-C mutants in quasispecies had more influence on HBeAg expression.Combined with the previous studies,it was speculated that the pre-C/BCP mutation may be the cause of low HBeAg and high HBV DNA in eP-CHB and lead to the recurrence after withdrawal of antiviral therapy.