Kuroki M, Kuroki M, Ichiki S, Matsuoka Y
Mol Immunol. 1984 Aug;21(8):743-6. doi: 10.1016/0161-5890(84)90028-2.
Unglycosylated peptide backbones of carcinoembryonic antigen (CEA) synthesized by human tumor cell lines in the presence of tunicamycin were identified and analyzed by SDS-polyacrylamide gel electrophoresis. Three tumor cell lines, QGP-1 (pancreas), FCC-1 (colon) and KNS-62 (lung) were found to produce CEA molecules of 180,000-190,000 mol. wts labeled with both [3H]leucine and [14C]glucosamine under conventional culture conditions. In contrast, in the presence of tunicamycin, the native CEA molecules disappeared, and a new component that was precipitated with anti-CEA antibodies and labeled only with [3H]leucine but not with [14C]glucosamine was identified in each cell line. Monoclonal antibodies each directed to different major antigenic determinants on the native CEA molecules also reacted with this unglycosylated peptide. The apparent mol. wts of the naked CEA peptides from QGP-1 and FCC-1 were equally about 78,000, whereas that from KNS-62 was somewhat larger than the other two, suggesting some differences in the peptide structure of the CEA molecules.
在衣霉素存在的情况下，由人肿瘤细胞系合成的癌胚抗原（CEA）的未糖基化肽骨架通过SDS-聚丙烯酰胺凝胶电泳进行鉴定和分析。发现三种肿瘤细胞系，即QGP-1（胰腺）、FCC-1（结肠）和KNS-62（肺），在常规培养条件下产生分子量为180,000 - 190,000的CEA分子，这些分子同时用[³H]亮氨酸和[¹⁴C]葡糖胺标记。相比之下，在衣霉素存在的情况下，天然CEA分子消失，并且在每个细胞系中都鉴定出一种新的成分，该成分能用抗CEA抗体沉淀，并且仅用[³H]亮氨酸标记，而不用[¹⁴C]葡糖胺标记。针对天然CEA分子上不同主要抗原决定簇的单克隆抗体也与这种未糖基化肽发生反应。来自QGP-1和FCC-1的裸CEA肽的表观分子量约为78,000，而来自KNS-62的则比其他两者略大，这表明CEA分子的肽结构存在一些差异。
