不同基因型HBV对药物反应性和S基因突变位点研究

Drug reactivity and mutations of S gene from different genotypes of hepatitis B virus

目的分析HBV不同基因型对药物反应性及S基因变异情况。方法收集遵义医学院附属医院于2016年3月至2017年7月就诊的186例HBV DNA阳性乙型肝炎患者的血清样本,根据是否用药分为治疗组130例和对照组56例,治疗组根据用药不同分为干扰素组、核苷(酸)类似物组、保肝药组和中成药组,分别提取HBV DNA后扩增S基因并测序,结合临床资料分析疗效与基因型相关性。结果对照组共51例患者扩增出S基因[91.1%(51/56),其中B基因型30例,C基因型21例],治疗组共有104例患者样本扩增出S基因[80.0%(104/130),其中B基因型62例,C基因型42例],均以B、C基因型为主。两种基因型对核苷(酸)类似物的反应性(肝功能改变、HBV DNA拷贝数)与未治疗组差异有统计学意义(P <0.01)。B基因型HBV S基因经核苷(酸)类似物作用后,第597位碱基鸟嘌呤G变为腺嘌呤A即183位苯丙氨酸(Phe/F)突变为缬氨酸(Val/V),使翻译终止。保肝药和干扰素引起131位鸟嘌呤G突变为腺嘌呤A,进而甘氨酸(Gly/G)变为谷氨酸(Glu/E),且9和213位氨基酸突变率为100%。C基因型HBV则发生26位胞嘧啶C突变为胸腺嘧啶T,即脯氨酸(P)变为亮氨酸(L)及53位点丝氨酸(Ser/S)突变为亮氨酸L。保肝药物作用主要引起68位点异亮氨酸(Ile/I)突变为苏氨酸(Thr/T)和49位点P变L。干扰素和中成药均可引起225位酪氨酸-异亮氨酸(YI)变为异亮氨酸-组氨酸(IH)和9位氨基酸P变L。结论不同HBV基因型对药物反应不同,B、C基因型HBV对药物反应可产生相同突变位点。

Objective To investigate the different genotypes of HBV on drug reactivity and variation of S gene. Methods Total of 186 specimens of hepatitis B patients with HBV DNA positive were collected in Affiliated Hospital of Zunyi Medical University from March of 2016 to July of 2017. According to whether or not using drugs, 186 specimens were divided into experimental group with 130 cases and control group with 56 cases. And the experimental group was divided into interferon group, nucleoside analogue group, hepatoprotective drug group, and Chinese Traditional Medicine group. HBV DNA were extracted and amplified and S gene were sequenced. While the correlation between genotype and clinical treatment were analyzed by clinical data analysis. Results S gene were amplified in 91.1%（51/56） samples in untreated group and 80.0%（104/130） samples in experimental group, mainly with B and C genotypes. The reactivity of the two genotypes（the changes of ALT, AST and HBV DNA） were significantly different compared with untreated group（P 〈0.01）. After reacted with nucleos（t）ide analogues, guanine at the 597 th alkaline of S gene in B genotype mutated to adenine, and Phenylalanine（Phe/F） at the 183 rd amino acid mutated to valine（Val/V）, then translation was terminated. The hepatoprotective drugs and interferon mainly cause the 131 st guanine changed to adenine, and Glycine（Gly/G） mutated to glutamic acid（Glu/E）, the mutation rate of the 9 th and 213 rd amino acid were 100%. Among the C genotype, cytosine at the 26 th site mutated to thymine, then Proline（Pro/P） mutated to Leucine（Leu/L） and serine（Ser/S） at the 53 rd site mutated into Leu. In the hepatoprotective drugs group, Isoleucine mutated to Threonine at the 68 th site and P changed into L at the 49 th site. Interferon and Chinese Traditional Medicine caused a common mutation with 225 bit TyrosineIsoleucine（TI） changing into Isoleucine-Hlstidinein（IH） for both genotype B and C HBV, and the 9 th Proline mutated to Leucine. Conclusions Different genotypes of HBV showed different reactivity to drugs, genotypes B and C could show the same mutation sites in S gene.