一种新的胰腺癌相关性自身抗原PAA47的纯化和鉴定

Purification and Identification of Pancreatic Cancer Associated Autoantigen 47

以往的研究发现 6 3 6 4 %的胰腺癌患者具有针对相对分子质量初步鉴定为 4 70 0 0的靶抗原的阳性共带 ,该条带仅在1 9%的正常人中查及 ,本研究旨在纯化并鉴定该靶抗原 ,以深入认识该独特的自身免疫现象在胰腺癌中的意义 ,探索靶抗原的生物学功能以及在临床诊断中可能应用价值。提取人喉癌上皮细胞 (Hep 2 )蛋白抗原 ,进行双向电泳 ,选取 8份以往在单向蛋白质印迹 (SDS PAGE )中 ,相对分子质量约为 4 70 0 0处有明显抗原抗体反应的胰腺癌患者血清进行免疫印迹分析。比较双向电泳凝胶图像、丽春红染色之蛋白质转印硝酸纤维素滤膜图像以及血清反应后滤膜图像 ,确定靶抗原在凝胶上的斑点 ,判断其等电点。切取胶上蛋白质斑点经胰蛋白酶消化后通过HPLC MS联用分析获得串级质谱数据 ;利用互联网搜索工具MASCOT分析处理数据并进行数据库查询 ,以鉴定靶抗原。结果表明 ,KIAA0 111的基因预测产物是一种新鉴定的胰腺癌相关性自身抗体靶抗原 。

Previous works had detected a new autoantigen in patients with pancreatic cancers,called pancreatic cancer associated autoantigen 47 (PAA47) which was found in 63 64% of patients with pancreatic cancers and 1 9% of healthy controls The aim of the present study was to purify and identify the target antigen of this autoantigen by using the antigens extracted from human epithelial cells (Hep 2) and sera of 8 cases of precreatic cancers as confirmed by the positive reaction with anti 47 kD sera by SDS PAGE that was separated with two dimensional electrophoresis and then followed by mass electrophoresis identification To get some informations on the conformation and biological function of the antigen protein,software MASCOT and BLAST were used These results indicate that the gene product of KIAA0111 is a novel pancreatic cancer associated autoantigen and might be a potential serological marker for the pancreatic cancers