乙型肝炎病毒相关慢加急性肝衰竭患者的病毒S基因准种变异特征分析

Analysis on quasispecies variation of S gene in patients with hepatitis B virus related acute-on-chronic liver failure

目的了解HBV相关慢加急性肝衰竭(HBV-ACLF)患者的病毒S基因准种变异特征,探讨HBV-ACLF可能的发生机制。方法将2016年1月至2018年10月高州市人民医院收治的HBV-ACLF患者和慢性乙型肝炎(CHB)患者纳入研究,收集患者基本资料以及治疗前血清样本。提取HBV DNA,巢式PCR法扩增HBV S基因,参照相应基因型标准序列,分析两组患者的HBV S基因的准种异质性差异,包括信息熵(Sn)、平均遗传距离(d*)、同义替换率(dS)、非同义替换率(dN)指标。结果成功扩增HBV S基因的患者共99例,其中HBV-ACLF患者56例,CHB患者43例。HBV S基因准种异质性分析显示,HBV-ACLF组的Sn(核苷酸、氨基酸)、dS、dN分别为(0.716±0.181)nt、(0.598±0.218)AA、8.259±2.607和7.103±3.081,均高于CHB组,差异均有统计学意义(t=2.579、2.546、8.232和5.297,P均<0.05)。S基因MHR区准种变异性分析结果显示,HBV-ACLF组的Sn(核苷酸、氨基酸)、d*(核苷酸、氨基酸)、dS、dN分别为(0.756±0.184)nt、(0.613±0.229)AA、(7.137±3.074)nt、(8.280±3.194)AA、9.091±2.720和7.429±2.860,明显高于CHB组,差异均有统计学意义(t=5.332,、5.020、3.599、5.772、4.093和3.857,P均<0.01)。结论HBV-ACLF患者更易发生S基因变异,尤其是MHR区变异,可能与HBV-ACLF产生相关。

Objective To understand the quasispecies variation of S gene in patients with HBV related acute-on-chronic liver failure(HBV-ACLF),so as to explore the possible mechanism of HBV-ACLF.Methods Patients with HBV infection in Gaozhou People's Hospital from January 2016 to October 2018 were enrolled and divided into HBV-ACLF group and chronic hepatitis B(CHB)group.The clinical data and blood samples before treatment were collected.HBV DNA in serum was extracted,and HBV S region was amplified by nest-PCR.According to the genotypic standard sequence,the quasispecies heterogeneity of HBV S gene including Shannon entropy(Sn),average genetic distance(d*),synonymous substitution rate(dS)and non-synonymous substitution rate(dN)was analyzed between the two groups.Results HBV S region was successfully amplified from 99 patients,including 56 cases in HBV-ACLF group and 43 cases in CHB group.The quasispecies heterogeneity of S gene showed that the Sn(nucleotide and amino acid),dS and dN in HBV-ACLF group were(0.716±0.181)nt,(0.598±0.218)AA,8.259±2.607 and 7.103±3.081,which were all significantly higher than those in CHB group(t=2.579,2.546,8.232 and 5.297,P all<0.05).The quasispecies heterogeneity of major hydrophilic region(MHR)in S gene showed that the Sn(nucleotide and amino acid),d*(nucleotide and amino acid),dS and dN in HBV-ACLF group were(0.756±0.184)nt,(0.613±0.229)AA,(7.137±3.074)nt,(8.280±3.194)AA,9.091±2.720 and 7.429±2.860,which were all significantly higher than those in CHB group(t=5.332,5.020,3.599,5.772,4.093 and 3.857,P all<0.01).Conclusions The S gene variation occurs more frequently in patients with HBV-ACLF,especially the MHRvariation which may be related to HBV-ACLF.