胰腺癌抗原SC6的分离及其特性分析

Purification and characterization of antigen SC6 for pancreatic cancer

目的获得胰腺癌重组噬菌体抗体筛检及鉴定的靶抗原．方法用ｐｒｏｔｅｉｎＡｓｅｐｈａｒｏｓｅ４Ｂ柱纯化的单抗ＳＣ６吸附到ＣＮＢｒｓｅｐｈａｒｏｓｅ４Ｂ特异亲合层析柱上，分离出ＳＣ６抗原，再用ＳＤＳＰＡＧＥ，Ｗｅｓｔｅｒｎｂｌｏｔｉｎｇ、免疫化学和氨基酸自动分析仪等检测其有关的特性．结果此抗原在ＳＤＳＰＡＧＥ，Ｗｅｓｔｅｒｎｂｌｏｔｉｎｇ上显示一条带，Ｍｒ６７００００，性质属糖蛋白，其中含１７种氨基酸，与ＣＡ１９９等多种抗原不同，在胰腺癌组织中的阳性表达率为９１２％．结论该抗原是一种与胰腺癌相关的新肿瘤标志物，这为其分子克隆等研究提供了新的抗原蛋白．

AIM To obtain a target antigen for planning recombinant phage antibody (RPA) of pancreatic cancer. METHODS Purification of the antigen was performed by affinity chromatography on CNBrsepharose 4B columns binding monoclonal antibody SC6 purified by protein Asepharose 4B columns. Nature of the purified antigen was examined by SDSPAGE, Western blotting, immunochemistry, automatic analyzer of aminoacid, etc. RESULTS Detected by SDSPAGE and Western blot,ting, the separated antigen was a single band. And this antigen was characterized as glycoprotein with a relative molecular weight of around 670000 and with 17 amino-acids. The antigenic determinant is different from those of CA199, Span-1, TAG-72 and several other cancer directed antibodies. 912% of pancreatic cancer specimens had SC6 reactivity. CONCLUSION The malignancy-associated structures identified by SC6 may provide new information on the carbohydrate and peptide structure of pancreatic cancer. And a new target antigen of screen and detection used in its RPA is provided by the antigen SC6.