Gipson I K, Spurr-Michaud S J, Tisdale A S, Kublin C, Cintron C, Keutmann H
Department of Ophthalmology, Massachusetts General Hospital, Boston 02114, USA.
Tissue Cell. 1995 Aug;27(4):397-404. doi: 10.1016/s0040-8166(95)80060-3.
The stratified squamous epithelia of the ocular surface, larynx, and vagina are mucus-coated epithelia, apices of which are subject to abrasive pressure from epithelia-epithelia interactions from eyelid, vocal cords, or vaginal folds, respectively. Mucus coats on these epithelia have generally been considered to be derived from the specialized mucin-producing cells embedded either in the epithelia or in adjacent tissues. Here we report the isolation, partial characterization, and cellular localization of a mucin-like glycoprotein produced by these stratified epithelia. In all three epithelia, the mucin-like molecule is present on cytoplasmic vesicles in subapical cells. As cells differentiate to their apical-most position adjacent to their mucus coat, the mucin-like molecule moves to the cell membrane where it is particularly prominent on microplicae folds. Lectin affinity chromatography was used to isolate the molecule from rat vaginal and corneal epithelium. Isolated material was approximately 60% carbohydrate and 40% protein. The major monosaccharide was N-acetylgalactosamine with lesser amounts of N-acetylglucosamine, galactose, mannose, xylose and fucose. Amino acid analysis demonstrated the predominant amino acids to be glycine, serine, threonine and proline. These data plus PAS and Alcian blue binding to the isolate indicate a mucin-like glycoprotein.
眼表、喉和阴道的复层鳞状上皮是有黏液覆盖的上皮，其顶端分别受到来自眼睑、声带或阴道皱襞上皮 - 上皮相互作用产生的摩擦压力。这些上皮上的黏液层通常被认为来源于嵌入上皮或相邻组织中的专门产生黏蛋白的细胞。在此我们报告这些复层上皮产生的一种黏蛋白样糖蛋白的分离、部分特性鉴定及细胞定位。在所有这三种上皮中，黏蛋白样分子存在于顶端下方细胞的细胞质囊泡上。随着细胞分化至其与黏液层相邻的最顶端位置，黏蛋白样分子移动至细胞膜，在微褶上尤其显著。采用凝集素亲和层析从大鼠阴道和角膜上皮中分离该分子。分离得到的物质约含60%的碳水化合物和40%的蛋白质。主要单糖为N - 乙酰半乳糖胺，还有少量的N - 乙酰葡糖胺、半乳糖、甘露糖、木糖和岩藻糖。氨基酸分析表明主要氨基酸为甘氨酸、丝氨酸、苏氨酸和脯氨酸。这些数据以及该分离物与过碘酸希夫试剂和阿尔辛蓝的结合表明其为一种黏蛋白样糖蛋白。
