Human hepatoma antigen analyzed by genetic engineering method

利用哺乳动物细胞系表达载体pcDNA3.1，将人肝癌细胞株Hep.3B2.1-7转化为不表达人类白细胞抗原A24基因的细胞株，在其细胞表面携带内源性抗原肽。表达3B2.1-7的人白细胞抗原-A24(3B.A24)的酸性洗脱产物经FPLO分级后，显示出7个不同于野生型和转MOKE的人肝癌3B2.1-7的显著峰。7个多肽中有1个在第二(L)和第10(K)位具有HIA-A24的锚定基序，而2个组分(H_2A)、1个巨噬细胞移动抑制因子(HIA-A68)结合肽、1个HIA-B35结合肽，本研究获得的人类白细胞抗原-A24结合肽的同源性研究表明，在数据库中没有发现同源蛋白质。综上所述，本研究有可能阐明一种新的人类白细胞抗原-A24结合肽，而利用基因工程方法强制表达的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.