Human hepatoma antigen analyzed by genetic engineering method

用哺乳动物细胞系表达载体pcDNA3.1将HLA-A_（24）cDNA导入不表达HLA-A_（24）基因的人肝癌细胞系Hep.3B2.1-7，使其细胞表面携带内源性抗原肽。HLA-A24基因克隆表达Hep.3B2.1-7的酸性电泳分析3B.A24经FPLO分级分离后，与野生型Hep.3B2.1-7和moke转染的Hep.3B2.1-7相比，在7个肽段中有1个肽段在第2（L）和第10（K）位具有HIA-A24锚定基序，而2个希斯顿H2 A，从剩余的6个组分中分离出1个HLA-A68结合肽、1个HIA-B35结合肽和2个未知肽，并对HLA-A24结合肽进行同源性分析，结果表明在数据库中没有同源蛋白，说明本研究有可能分离出一个新的HLA-A24结合肽，用基因工程方法强制表达HLA等分子，将为肿瘤抗原肽的研究开辟一条新的途径。

Human hepatoma cell line, Hep.3B2.1-7 that has no HLA-A24 gene expression, has been transduced of HLA-A24 cDNA by using mammalian cell line expression vector pcDNA3 .1 in order to carry the endogenous antigenic peptides on its cell surface. The acidic eluate of cloned HLA-A24 expressing Hep.3B2.1-7 (Hep.3B.A24) demonstrated seven significant peakes that were different from wild type Hep.3B2.1-7 and moke-transfected Hep.3B2.1-7 after FPLO fractionations.One out of seven peptide fraction had anchoring motief for HIA-A24 at second (L) and tenth (K) positions, while two histon H2A, one HLA-A68 binding peptide of macrophage migration inhibiting factor, one HIA-B35 binding peptide, and two unknown peptides were clarified from remaining six fractions.The homology research of HLA-A24 binding peptide obtained in present study demonstrated no homologous protein in data base.In conclusion, present study is possible to clarify a novel HLA-A24 binding peptide, and HLA.molecules enforced to express by genetic engineering method will open a new avenue for the research in tumor-antigenic peptides.