Immunohistochemical localization of beta1,4-galactosyltransferase in human normal and neoplastic pancreatic tissues

beta1, 4-半乳糖基转移酶 (GalTase) 是高尔基体中的糖基转移酶，可将半乳糖从 UDP-半乳糖转移至糖复合物中的末端 N-乙酰葡糖胺残基，并形成 beta1,4 连接。肿瘤的糖基转移酶本身的碳水化合物部分经历各种变化。这个过程也表明糖基转移酶本身发生变化的可能性。因此，我们检查了正常和肿瘤外分泌组织中针对 GalTase 的单克隆抗体 (MAb8628) 的结合模式。使用从外科手术获得的十个正常和II肿瘤性人外分泌胰腺组织。将冰冻切片与该抗体一起孵育。正常导管细胞和腺泡细胞的核上区域和终条在光镜水平上显示出 GalTase 阳性染色。腺泡中心细胞在其笔核区域显示阳性染色。肿瘤细胞的核上区域和末端条也被染色。肿瘤细胞的核上区域发育良好，并且与正常细胞相比染色强烈。在电子显微镜水平上看到，核上区域和终端条分别对应于高尔基体的横池和连接复合体（即紧密连接和粘附连接）。胰腺肿瘤变化导致高尔基体中GalTase表达增加，这种增加可能对胰腺上皮细胞间的细胞间粘附和通讯产生重要影响。测量这种酶可用于诊断正常组织的外分泌胰腺肿瘤变化。

beta1, 4-galactosyltransferase (GalTase) is the glycosyltransferase in the Golgi apparatus that transfers galactose from UDP-galactose to terminal N-acetylglucosamine residues in glycoconjugates with formation of beta1,4 linkage. Neoplasms undergo various changes in the carbohydrate moieties of their glycosyltransferase themselves. This process also indicates the possibility of changes in glycosyltransferase themselves. Therefore, we examined the binding pattern of a monoclonal antibody (MAb8628) against GalTase in both normal and neoplastic exocrine tissues. Ten normal and II neoplastic human exocrine pancreatic tissues obtained from surgical operations were used. Frozen sections were incubated with this antibody. Supra-nuclear regions and terminal bars of normal duct cells and acinar cells revealed positive staining for GalTase at the light microscopic level. Centroacinar cells revealed positive staining in their pen-nuclear region. Neoplastic cells were also stained in their supra-nuclear regions and terminal bars. Supra-nuclear regions were well developed in neoplastic cells and intensely stained compared with those in normal cells. The supra-nuclear regions and the terminal bars corresponded to the trans cistern of the Golgi apparatus and the junctional complex (i. e. , tight junction and adherens junction), respectively, seen at the electron microscopic level. Pancreatic neoplastic changes thus lead to an increase in the expression of GalTase in the Golgi apparatus, which increase may have an important effect on the intercelluar adhesion and communication among pancreatic epithelial cells. Measurement of this enzyme is useful for diagnois of exocnine pancreatic neoplastic change from normal tissues.