乙型肝炎病毒表面抗原突变体稳定表达细胞系的建立和抗原性鉴定  

Establishment of stable expression cell lines for HBsAg variants and analysis of antigenicity

作　　者：王战会 齐义鹏[1] 林裕龙[2] 骆抗先[2] 侯金林[2] 

机构地区：[1]武汉大学生命科学学院 [2]同和南方医院感染内科

出　　处：《中华实验和临床病毒学杂志》2004年第1期47-50,共4页Chinese Journal of Experimental and Clinical Virology

基　　金：国家"973"资助课题 (19990 5 410 6) ;国家自然科学基金重点课题 (3 963 0 2 80 )

摘　　要：目的　探讨乙型肝炎 (乙肝 )病毒 (HBV)表面抗原 (HBsAg)阴性HBV感染的分子机制。方法　在对 4 6例HBsAg阴性但血清HBVDNA阳性感染者的S基因序列进行分析的基础上 ,构建了 6株新的HBsAg变异株 (4株联合点突变株 ,2株插入变异株 )的EBO plpp真核表达载体 ,并转染了COS7细胞 ,建立了这 6株HBsAg变异株的稳定表达细胞系。分别用酶联免疫法 (ELISA)和放射免疫法(RIA)对细胞表达的HBsAg抗原性进行检测。结果　除 1例插入变异株可检测到较弱的阳性外 ,其余5株均检测不到HBsAg的存在。结论　新发现的HBsAg联合点突变和氨基酸插入变异 ,均对HBsAg的抗原性有负面的影响 ,是造成HBsAg阴性HBV感染的直接原因。Objective To study the mechanism of hepatitis B virus infected patients who is negative for HBsAg. Methods DNA sequences of 46 patients were analyzed. In these patients,HBsAg was negative but HBV DNA was positive and six new HBsAg variants were identified. Four of the six variants were combined point mutants and two were insertion variants.These S genes were subcloned into eukaryotic expression vector EBO-plpp,and the recombinant eukaryotic expression plasmids were transfected into COS7 cells. Cell lines expressing mutant-type HBsAg were obtained. The supernatants were detected by ELISA and RIA. Results Only the two-aminoacid-insertion variants could be detected and the others failed to react with poloyclonal and monoclonal antibodies against HBsAg. Conclusion The results indicated that the point mutations and insertions may result in a conformational change of the S gene,which affect HBsAg antigenicity,suggesting a posible relationship between the variants and the negative conversion of HBsAg of the patients.

关 键 词：乙型肝炎病毒 表面抗原 基因突变 细胞系 抗原性 鉴定 分子机制 

分 类 号：R392[医药卫生—免疫学]