Decaens C, Gautier R, Bara J, Daher N, Le Pendu J, Burtin P
Laboratoire d'Immunochimie, ER 277 CNRS, I.R.S.C., Villejuif, France.
Cancer Res. 1988 Mar 15;48(6):1571-7.
We report the characterization of an IgG2a monoclonal antibody, (MAb) 660, prepared against rat gastric high molecular weight glycoproteins. By immunoperoxidase staining, MAb 660 reacted only with the mucous cells of surface gastric epithelium and with a few duodenal goblet cells close to the pylorus in normal adult rats. In fetuses, it reacted with intestinal and colonic goblet cells. The adult colon was always negative. The MAb 660 stained 100% (30 of 30) of chemically induced colonic carcinomas and 100% (7 of 7) of duodenal carcinomas. Several weeks before the appearance of tumors, histologically normal glands, then hyperplasia and dysplasia were precociously stained with MAb 660. The tissue distribution was different from that of blood group related antigens and M1 fucomucins. The recognized antigen was not sensitive to neuraminidase treatment. After electrophoresis in polyacrylamide gel, staining with periodic acid-Schiff reagent and Western blotting showed that the MAb 660 recognized an epitope associated with high molecular weight glycoproteins. This epitope was unaffected by beta-mercaptoethanol reduction-periodate treatment and neuraminidase and trypsin digestion. However, trypsin digestion performed after beta-mercaptoethanol reduction destroyed the 660 epitope. These data suggest that the antibody could recognize the peptide moiety of the mucin rather than its carbohydrate moiety. Thus, the new antigen identified by MAb 660 is a mucin-type glycoprotein with an oncofetal behavior in the rat colon and is precociously expressed by precancerous colonic mucosa.
我们报告了一种针对大鼠胃高分子量糖蛋白制备的IgG2a单克隆抗体（MAb）660的特性。通过免疫过氧化物酶染色，MAb 660仅与正常成年大鼠胃表面上皮的黏液细胞以及靠近幽门的少数十二指肠杯状细胞发生反应。在胎儿中，它与肠道和结肠杯状细胞发生反应。成年结肠始终呈阴性。MAb 660对100%（30例中的30例）化学诱导的结肠癌和100%（7例中的7例）十二指肠癌进行了染色。在肿瘤出现前几周，组织学上正常的腺体、随后的增生和发育异常均被MAb 660早熟染色。其组织分布与血型相关抗原和M1岩藻糖黏液素不同。所识别的抗原对神经氨酸酶处理不敏感。在聚丙烯酰胺凝胶中电泳、用高碘酸-希夫试剂染色和蛋白质印迹分析表明，MAb 660识别与高分子量糖蛋白相关的一个表位。该表位不受β-巯基乙醇还原-高碘酸盐处理、神经氨酸酶和胰蛋白酶消化的影响。然而，在β-巯基乙醇还原后进行的胰蛋白酶消化破坏了660表位。这些数据表明，该抗体能够识别黏蛋白的肽部分而非其碳水化合物部分。因此，由MAb 660鉴定的新抗原是一种在大鼠结肠中具有癌胚行为的黏蛋白型糖蛋白，并由癌前结肠黏膜早熟表达。
