人胰腺癌相关粘蛋白核芯多肽的提取与特性

Isolation and Characterization of Polypeptide Core of Human Adenocarcinoma-Associated Mucin

应用分子筛层析及氯化铯密度梯度离心从人胰腺癌细胞株SW1990提取、纯化获得粘蛋白,再用氟氢酸去除粘蛋白的碳水化合物而获得核芯肽。对粘蛋白核芯肽进行了氨基酸组份分析,并以免疫印迹及ELISA法进行免疫原分析,结果表明所提取的核芯肽至少含有Muc-1,Muc-2,及Muc-3三种不同氨基酸序列的多肽,免疫印迹表明此核芯肽含有从28至大于90KD的多条肽。在此基础上,制备了抗此核芯肽的单克隆抗体,5株单克隆抗体与多种癌细胞起反应,但多不与正常组织起反应,仅一株单克隆抗体MY-5与部分正常组织反应。这为进一步观察癌相关核芯肽病理生理功能打下了基础。

To study the molecular properties of polypeptide core of human mucin antigens, a polypeptide core of mucin (apomucin) was isolated from human pancreatic cancer cell line SW1990.The tumor mucin was isolated by a combination of molecular sieve chromatography and CsCl density gradient ultracentrifugation. Anhydrous hydrogen flouride was employed to remove carbohydrate units from purified mucin molecules. The purity of mucin and apomucin were identified by SDS-PAGE, the amino acids of apomucin were analized and confirmed by Western Blot using anti-apomucin antibodies.A bunch of monoclonal antibodies were generated against this apomucin. The results showed that this isolated apomucin consisted of many different cDNA sequences peptides, included MUC-l,MUC-2 and MUC-3. The monoclonal antibodies against this apomucin reacted with peptides of molecular weight from 28 to >90 KD.A11 the five monoclonal antibodies against this apomucin reacted with cancer cell lines and cancer tissues,while only one also reacted with normal tissues.