Cohen R E, Noble B, Neiders M E, Comeau R L
Departments of Periodontology and Oral Biology, School of Dental Medicine, State University of New York at Buffalo 14214, USA.
Arch Oral Biol. 1995 Nov;40(11):1015-21. doi: 10.1016/0003-9969(95)00072-w.
The purpose of this study was to analyse the phenotypical distribution of resident cells of the mononuclear phagocyte system in rat salivary glands, and to determine whether isoproterenol induces alterations in macrophage and lymphocyte surface-marker expression. Frozen sections of gland tissues were prepared from five normal rats, and from six rats treated with 20 mg/kg isoproterenol/day for 10 days. A panel of six monoclonal antibodies was used to identify membrane markers associated primarily with monocytes (ED1), mature tissue macrophages (ED2), lymphoid macrophages (ED3), MHC class II (Ia) antigens (OX6), CD5-positive T lymphocytes (OX19), and rat B lymphocytes (OX33). Double-labelling techniques were used to detect the coexpression of ED1/ED2 and OX6/ED2 mononuclear cell markers in the major salivary glands. ED2-positive macrophages were predominant in all three major glands, ranging from 96 cells/0.87 mm2 field in the parotid gland to 165 cells/0.87 mm2 in the submandibular. OX19-positive T lymphocytes were rarely observed in submandibular and parotid glands but represented a distinguishing feature of the sublingual. Moderate numbers of ED3-positive macrophages also were detected in sublingual tissues. In the submandibular and parotid glands, isoproterenol resulted in a decrease in ED2-positive cells, but ED2-positive macrophages increased in sublingual glands with isoproterenol. Isoproterenol resulted in a decrease in MHC class II antigen expression on submandibular and sublingual mononuclear cells but an induction of Ia antigen in the parotid gland. Double labelling revealed that isoproterenol induced coexpression of ED1/ED2 markers on mononuclear cells in the submandibular glands, but ED1/ED2-positive cells were absent from other glands. However, coexpression of MHC class II markers on ED2-positive cells in the sublingual and parotid glands of normal rats was frequently observed, with isoproterenol decreasing coexpression in the sublingual gland and increasing it in the parotid. B lymphocytes were not detected in any of the glands examined. These findings indicate that important differences exist in normal resident mononuclear cell subsets among the major salivary glands of the rat. The differential effects of isoproterenol on inflammatory cells may reflect important differences in local salivary gland immunoregulation. Although salivary gland inflammation induced by isoproterenol does not appear to result from immune mechanisms, the rich population of T lymphocytes and ED3-positive macrophages, and presence of MHC class II antigens, suggest that the sublingual gland may function as an immune organ and have a role in mucosal immunity.
本研究的目的是分析大鼠唾液腺中单核吞噬细胞系统驻留细胞的表型分布，并确定异丙肾上腺素是否会诱导巨噬细胞和淋巴细胞表面标志物表达的改变。从五只正常大鼠以及六只每天接受20 mg/kg异丙肾上腺素治疗10天的大鼠身上获取腺体组织的冰冻切片。使用一组六种单克隆抗体来识别主要与单核细胞（ED1）、成熟组织巨噬细胞（ED2）、淋巴样巨噬细胞（ED3）、MHC II类（Ia）抗原（OX6）、CD5阳性T淋巴细胞（OX19）和大鼠B淋巴细胞（OX33）相关的膜标志物。采用双重标记技术检测主要唾液腺中ED1/ED2和OX6/ED2单核细胞标志物的共表达情况。ED2阳性巨噬细胞在所有三大腺体中均占主导地位，从腮腺中每0.87 mm²视野96个细胞到颌下腺中每0.87 mm² 165个细胞不等。OX19阳性T淋巴细胞在颌下腺和腮腺中很少见，但却是舌下腺的一个显著特征。在舌下组织中也检测到中等数量的ED3阳性巨噬细胞。在颌下腺和腮腺中，异丙肾上腺素导致ED2阳性细胞减少，但在接受异丙肾上腺素处理的舌下腺中ED2阳性巨噬细胞增加。异丙肾上腺素导致颌下腺和舌下腺单核细胞上MHC II类抗原表达减少，但在腮腺中诱导Ia抗原表达。双重标记显示，异丙肾上腺素诱导颌下腺单核细胞上ED1/ED2标志物共表达，但其他腺体中不存在ED1/ED2阳性细胞。然而，在正常大鼠的舌下腺和腮腺中，经常观察到ED2阳性细胞上MHC II类标志物共表达，异丙肾上腺素使舌下腺中共表达减少，而在腮腺中增加。在所检查的任何腺体中均未检测到B淋巴细胞。这些发现表明，大鼠主要唾液腺中正常驻留单核细胞亚群存在重要差异。异丙肾上腺素对炎症细胞的不同影响可能反映了局部唾液腺免疫调节的重要差异。虽然异丙肾上腺素诱导的唾液腺炎症似乎并非由免疫机制引起，但丰富的T淋巴细胞和ED3阳性巨噬细胞群体以及MHC II类抗原的存在表明，舌下腺可能作为一个免疫器官发挥作用，并在黏膜免疫中发挥作用。
