我国主要乙型肝炎病毒流行株中C抗原18～27位细胞毒性T淋巴细胞表位特点分析  

Characteristics of HBcAg（18-27） CTL epitopes of the main epidemic HBV strains in China

作　　者：马世武[1] 梁敏锋[1] 于乐成[1] 王战会[1] 周彬[1] 侯金林[1] 

机构地区：[1]南方医科大学南方医院感染内科,广州510515

出　　处：《中华肝脏病杂志》2008年第2期93-96,共4页Chinese Journal of Hepatology

基　　金：国家自然科学基金（30571662）;中国博士后科学基金（2004036019）

摘　　要：目的探讨我国HBV感染者中人类白细胞抗原（HLA）-A＊0201限制性特异性细胞毒性T淋巴细胞（CTL）表位HBcAg（17-27）V／I变异体的病毒学背景特点。方法应用生物信息学方法分析GenBank中30条不同HBV基因型的病毒株HBcAg（18-27）区段的序列特点。设计错配引物，构建针对HBVB、C基因型HBcAg／18-27）V／I的PCR-限制性片段长度多态性分析（RFLP）筛选方法。以PCR—RFLP和测序方法检测来自我国8省区160份HBV基因型B、C标本的HBcAg（18-27）V／I基因特点。用表位预测网站分析不同HBcAg（18-27）特异性CTL表位基因变异体与HLA-A＊0201分子结合力的差异。结果成功构建了针对HBV基因B、C型HBcAg（18-27）V／I的PCR—RFLP筛选方法；在调查的HBVB、C基因型血清中发现HBcAg（18-27）V的阳性率仅为1．88％（3／160）；生物信息学分析显示HBcAg（18～27）I与HLA—A＊0201分子的结合力明显低于HBcAg（18-27）V（HLA Ligand评分123与156，SYFPEITHI评分22与24）。结论我国流行的主要HBV流行株中HBcAg（18～27）的最后一位氨基酸主要表现为异亮氨酸，而非缬氨酸；在进行细胞免疫学研究时，以HBcAg（18-27）V作为参照需要充分考虑这一病毒学背景。Objective To study the characteristics of the virology background of HLA-A2 restricted HBcAg（18-27） epitope mutations in HBV infected patients in China. Method 30 HBV sequences with different genotypes from Genbank were analyzed by bioinformatics and the mismatched primers were designed for constructing a PCR-RFLP method to screen HBcAg（18-27）V/I in China. The distributions of HBcAg（18-27）V/I of 160 samples with HBV genotype B/C infection from 8 areas in China were screened and analyzed by PCRRFLP and sequencing. The aiTmity of HBcAg（18-27）V/I to HLA-A0201 was analyzed through referencing the bioinformatics websites. Results We successfully constructed a PCR-RFLP method for screening nlcAg（18-27） V/I from genotype B/C, and only 3 samples with HBcAg（18-27）V sequence were found in the 160 samples （3/160, 1.88%）. The aiTmity of HBcAg（18-27）I to HLA-A＊0201 was lower than the one of HBcAg（18-27）V through bioinformatic analysis （HLA ligand score was 123 vs 156, and the SYFPEITHI score was 22 vs 24）. Conclusion The last amino acid of most HBcAg（18.27） sequences of epidemic HBV strains in China is isoleucine, and not valine. Therefore HBcAg（18-27） sequence background in different HBV genotypes should be thoroughly considered when using it as a reference or control in immunological research about HBV.

关 键 词：肝炎 乙型 慢性 表位 基因型 变异 

分 类 号：R51[医药卫生—内科学]