Ogiso M, Shogomori H, Hoshi M
Cell and Information, PRESTO, Japan Science and Technology Corporation (JST) and Department of Life Science, Faculty of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama 226, Japan.
Glycobiology. 1998 Jan;8(1):95-105. doi: 10.1093/glycob/8.1.95.
Mammalian lens contains several neutral and acidic glycosphingolipids, the core structures of which are ganglio-, neolacto-, globo-, and isoglobo-series sugar chains. Old World monkey lens shows glycosphingolipid compositions similar to those of human cataractous lens, in particular the presence of Lewisxand sialyl-Lewisxepitopes and the absence of alpha-galactosyl epitope. Dog and pig lenses contain globotriaosylceramide and the sialyl-Lewisxcontaining neolactotetraosylceramide, respectively, which were found in primate lens, together with the alpha-galactosyl epitope containing neolactotetraosylceramide. Thin-layer chromatography immunostaining revealed the enrichment of some neolacto-series glycosphingolipids in the cortical and nuclear fibers, but not in lens epithelia, of dog, pig, and Japanese monkey lenses. Immunohistochemical studies confirmed the expression of Lewisx, sialyl-Lewisx, and alpha-galactosyl epitopes in the inner cortical and nuclear fibers, in association with the differentiation and maturation of lens epithelial cells to lens fibers. Glycobiological approaches thus suggested that some neolacto-series glycosphingolipids are involved in lens fiber development, in which the physiological roles of the alpha-galactosyl epitope are evolutionarily replaced by the Lewisxand sialyl-Lewisxepitopes in Old World monkeys and humans.
哺乳动物晶状体含有多种中性和酸性糖鞘脂，其核心结构为神经节系列、新乳糖系列、球系列和异球系列糖链。旧世界猴晶状体的糖鞘脂组成与人类白内障晶状体相似，特别是存在Lewisx和唾液酸化Lewisx表位，且不存在α - 半乳糖基表位。狗和猪的晶状体分别含有球三糖神经酰胺和含唾液酸化Lewisx的新乳糖四糖神经酰胺，在灵长类晶状体中也发现了这些物质，同时还有含α - 半乳糖基表位的新乳糖四糖神经酰胺。薄层色谱免疫染色显示，狗、猪和日本猕猴晶状体的皮质和核纤维中一些新乳糖系列糖鞘脂含量丰富，但晶状体上皮细胞中没有。免疫组织化学研究证实，Lewisx、唾液酸化Lewisx和α - 半乳糖基表位在皮质内层和核纤维中表达，与晶状体上皮细胞向晶状体纤维的分化和成熟有关。因此，糖生物学方法表明，一些新乳糖系列糖鞘脂参与晶状体纤维发育，其中α - 半乳糖基表位的生理作用在旧世界猴和人类中已在进化上被Lewisx和唾液酸化Lewisx表位所取代。
