Inoue M, Yamashina I, Nakada H
Department of Biochemistry, Faculty of Engineering, Kyoto Sangyo University, Kita-ku, Kyoto, 603, Japan.
Biochem Biophys Res Commun. 1998 Apr 7;245(1):23-7. doi: 10.1006/bbrc.1998.8369.
A synthetic peptide corresponding to the human MUC2 tandem repeat domain containing 14 Thr residues was glycosylated in vitro using UDP-GalNAc and microsomal membranes of the colorectal cancer cell line, LS180. The products were fractionated by reverse phase HPLC, which gave seven glycopeptide fractions. Their molecular weights were estimated by matrix-assisted laser desorption/ionization mass spectrometry, the values obtained corresponding to glycopeptides containing from one to ten GalNAc residues. On solid phase radioimmunoassaying involving a monoclonal anti-Tn antibody (MLS128), it was found that the glycopeptides containing nine or ten GalNAc residues were strongly immunoreactive, whereas the glycopeptides containing less than six GalNAc residues were inactive, indicating that a cluster of GalNAc-Thr is essential for the Tn antigenicity.
使用UDP-GalNAc和结肠癌细胞系LS180的微粒体膜，在体外对包含14个苏氨酸残基的人MUC2串联重复结构域对应的合成肽进行糖基化。产物通过反相高效液相色谱进行分离，得到七个糖肽组分。通过基质辅助激光解吸/电离质谱法估计它们的分子量，所得值对应于含有一至十个GalNAc残基的糖肽。在涉及单克隆抗Tn抗体（MLS128）的固相放射免疫测定中，发现含有九个或十个GalNAc残基的糖肽具有强免疫反应性，而含有少于六个GalNAc残基的糖肽无活性，这表明GalNAc-Thr簇对于Tn抗原性至关重要。
