与胃肠粘液核心多肽骨架反应的抗人胃癌单克隆抗体GL-013

REACTIVITY OF AN ANTI-HUMAN GASTRIC CARCINOMA MONOCLONAL ANTIEODY WITH GASTROINTESTINAL MUCIN CORE-RELATED PEPTIDES

抗人胃肠癌大分子糖蛋白抗原的单抗GL-013(IgG_1),其所识别抗原决定簇的进一步分析表明:与CEA、NCA、血型前体y配基和大肠癌组织次氯酸提取物及全脂成分提取物均无反应;然而,GL-013单抗与人胃肠粘液核心多肽骨架的人工合成肽链序列有较强的反应,并发现其是目前唯一一个识别富含苏氨酸的七肽决定簇的人胃肠粘液核心多肽骨架的单抗。免疫组化证实,其抗原表达于胃肠粘膜杯状细胞中,免疫电镜定位于细胞的粘液泡中。本文对此单抗在胃肠癌诊治中的意义进行了讨论。

A murine anti-human gastric carcinoma monoclonal antibody GL-013, which had been shown to react with a high molecular weight glycoprotein from gastrointestinal tumor tissue, failed to bind to a series of purified and partially purified antigens associated with tumors of the gastrointestinal tract. These included carcinoembryonic antigen (CEA), normal cross-reacting antigen (NCA), Y-hapten glycoproteins, and perchloric acid extracts and glycolipid preparations from colorectal tumors. However, the GL-013 antibody bound strongly to synthetic peptides with sequences based upon that reported for the protein core of a human gastrointestinal mucin. The findings suggest that the GL-013 antibody defines a threonine-rich peptide epitope expressed within the protein core of gastrointestinal mucins. The immunohistochemical distribution of its antigen was found in the golblet cels of the colorectal mucosa and located in mucin bubble by of cells immunoelectric microscope.