肝癌相关抗原SMP-30羧基端基因的构建、表达及血清学分析

Recombination and expression of hepatocellular carcinoma associated antigen SMP 30 and preliminary survey of its serum immunology

目的 :用基因工程的方法构建、表达和纯化肝癌肿瘤相关抗原衰老标记蛋白 30 (SMP 30 ) ,检测肝癌、肝硬化及其它肿瘤病人血清中相应抗体的阳性率。方法 :PCR方法扩增经SEREX技术筛选出的人肝细胞癌相关抗原SMP 30羧基末端16 5个氨基酸的DNA序列 ,构建其表达质粒 ,经原核表达和亲和层析纯化获得目的蛋白 ,经N 末端氨基酸序列测序证实为SMP 30蛋白。采用ELISA方法检测肝癌、肝硬化与其他肿瘤患者血清中抗SMP 30抗体的阳性率。结果 :以 6 3例正常人血清为对照 ,肝癌、慢性肝炎、肝硬化和鼻咽癌血清中SMP 30抗体阳性率分别为 39 7% (2 3 5 8)、2 1 9% (7 32 )、6 4 7% (11 17)和2 1 6 % (5 2 3)。 7例肺癌和 2 5例胃肠疾病中无一例阳性。Westernblot亦显示部分肝癌患者血清存在有SMP 30蛋白抗体。结论 :SMP 30蛋白抗体检测可望作为肝癌和肝硬化等疾病的血清学诊断指标之一。

Objective:To obtain and purify hepatocellular carcinoma associated antigen SMP 30 for study of its serum immunology in the patients with hepatocellular carcinoma,hepatocirrhosis and other diseases.Methods:The cDNA that represents 165 amino acids of SMP 30 in its C end was amplified and then recombined in expressing plasmid.The SMP 30 fusion protein was expressed in E.coli and was purified by affinity chromatographer.The N end 15 amino acids of SMP 30 were correct by sequence analysis.Sera from 162 patients and 63 normal idividuals were tested for antibody to SMP 30 in ELISA using recombinant SMP 30 protein.Results:ELISA results showed that 23/58 of hepatocellular carcinoma,7/32 of chronic hepatitis,11/17 of hepatocirrhosis and 5/23 of nasopharynx cancer patients had antibody against SMP 30.No antibody of SMP 30 was detected in the sera of 7 lung cancers,25 gastric intestine patients and 63 normal individuals.SMP 30 antibody also was detected in sera of hepatocellular carcinoma by Western blot.Conclusion:SMP 30 protein could be used for liver tumor antigen and liver disases seroreactivity seroscreening. [