Girardet C, Vacca A, Schmidt-Kessen A, Schreyer M, Carrel S, Mach J P
J Immunol. 1986 Feb 15;136(4):1497-503.
Two different monoclonal antibodies (MAb), called L-D1 and L-C5, were produced after immunization with either intact cells or the methanol phase of glycolipid extracts, respectively, from the same human colon carcinoma line, LoVo. As determined by an antibody-binding radioimmunoassay (RIA) on intact cells, MAb L-D1 and MAb L-C5 were highly reactive with all five colon carcinoma lines tested and with only one out of the 21 cell lines of various tissue origin tested. No reactivity of either MAb was observed with peripheral blood lymphocytes, granulocytes, or erythrocytes from healthy donors of various blood groups. Both MAb were tested in competitive binding experiments with an anti-CEA MAb from our laboratory (CEA 35) and with two previously described anti-colon carcinoma MAb from the Wistar Institute called 1083-17-1A (17-1A) and NS-19.9. In competitive binding experiments, MAb L-D1 was inhibited by MAb 17-1A and reciprocally, whereas MAb L-C5 was not inhibited by any of the other MAb tested. MAb L-D1 precipitated a major protein band with an apparent molecular weight (MW) of 41 kilodaltons (kD); interestingly, MAb 17-1A, which was reported to react with an uncharacterized antigen, precipitated the same protein band of 41 kD. This was confirmed with immunodepletion experiments. Furthermore, after treatment of the colon carcinoma cell line with tunicamycin, both MAb L-D1 and 17-1A precipitated a protein band of 35 kD. This shift of 6 kD suggests that the glycoprotein recognized by these 2 MAb contains two to three N-linked carbohydrate side chains. MAb L-C5 precipitated a group of three to four protein bands ranging from 43 to 53 kD that were not modified by tunicamycin treatment. A preliminary study conducted by using immunoperoxidase labeling on frozen sections of primary colon carcinoma showed that the two new MAb react strongly with these tumors, but also weakly with the normal adjacent mucosa, as did the other anti-colon carcinoma MAb tested.
分别用来自同一人结肠癌细胞系LoVo的完整细胞或糖脂提取物的甲醇相免疫后，产生了两种不同的单克隆抗体（MAb），称为L-D1和L-C5。通过对完整细胞进行抗体结合放射免疫测定（RIA）确定，MAb L-D1和MAb L-C5与所有测试的5种结肠癌细胞系高度反应，而在测试的21种不同组织来源的细胞系中仅与其中1种反应。未观察到这两种MAb与来自不同血型健康供体的外周血淋巴细胞、粒细胞或红细胞有反应。两种MAb都与我们实验室的一种抗癌胚抗原（CEA）单克隆抗体（CEA 35）以及两种先前描述的来自维斯塔研究所的抗结肠癌单克隆抗体1083-17-1A（17-1A）和NS-19.9进行了竞争结合实验。在竞争结合实验中，MAb L-D1被MAb 17-1A抑制，反之亦然，而MAb L-C5未被测试的任何其他MAb抑制。MAb L-D1沉淀出一条主要蛋白带，其表观分子量（MW）为41千道尔顿（kD）；有趣的是，据报道与一种未鉴定抗原反应的MAb 17-1A沉淀出相同的41 kD蛋白带。免疫去除实验证实了这一点。此外，用衣霉素处理结肠癌细胞系后，MAb L-D1和17-1A都沉淀出一条35 kD的蛋白带。6 kD的这种变化表明这两种MAb识别的糖蛋白含有两到三条N-连接的碳水化合物侧链。MAb L-C5沉淀出一组三到四条蛋白带，范围在43至53 kD之间，这些蛋白带未被衣霉素处理所改变。通过对原发性结肠癌冰冻切片进行免疫过氧化物酶标记进行的初步研究表明，这两种新的MAb与这些肿瘤强烈反应，但与相邻正常黏膜也有微弱反应，其他测试的抗结肠癌单克隆抗体也是如此。
