Mullins R F, Johnson L V, Anderson D H, Hageman G S
Anheuser-Busch Eye Institute of St. Louis University, Department of Ophthalmology, St. Louis University School of Medicine, MO 63104, USA.
Ophthalmology. 1997 Feb;104(2):288-94. doi: 10.1016/s0161-6420(97)30322-4.
Drusen are extracellular deposits that accumulate between the basal lamina of the retinal pigment epithelium and the elastic lamina of Bruch membrane in aging human eyes. Although specific types of drusen are recognized as significant risk factors for the development of both the atrophic and exudative forms of age-related macular degeneration, few studies have focused on defining their molecular composition. As an initial step toward identifying the molecular composition of drusen, assessing the biochemical relation between hard and soft drusen, and identifying potential target molecules for detecting drusen clinically, the authors have analyzed their carbohydrate composition using lectin histochemistry.
Sections of eyes from human donors containing a spectrum of hard and soft drusen were screened with a battery of 22 fluorescein-conjugated lectins.
A specific subset of six lectins bind drusen intensely. No significant differences in lectin binding are observed between any subclass of hard and soft drusen. Some drusen exhibit homogeneous, uniform labeling, whereas others show asymmetrical, heterogeneous distribution of glycoconjugates.
This study shows that glycoconjugates containing specific carbohydrate residues are present in all classes of hard and soft drusen examined. The observation that hard and soft drusen are bound by the same lectins suggests that they may be related compositionally. Identification of the drusen-associated glycoconjugates shown in this investigation will facilitate studies of drusen genesis and their involvement in the pathogenesis of age-related maculopathy. They may also provide a basis for developing avenues of therapeutic intervention.
玻璃膜疣是细胞外沉积物，在衰老的人眼中积聚于视网膜色素上皮的基底层和布鲁赫膜的弹性层之间。尽管特定类型的玻璃膜疣被认为是萎缩性和渗出性年龄相关性黄斑变性发展的重要危险因素，但很少有研究专注于确定其分子组成。作为确定玻璃膜疣分子组成、评估硬性和软性玻璃膜疣之间生化关系以及确定临床上检测玻璃膜疣的潜在靶分子的第一步，作者使用凝集素组织化学分析了它们的碳水化合物组成。
用一组22种荧光素偶联凝集素筛选含有一系列硬性和软性玻璃膜疣的人类供体眼切片。
六种凝集素的一个特定亚组与玻璃膜疣强烈结合。在硬性和软性玻璃膜疣的任何亚类之间未观察到凝集素结合的显著差异。一些玻璃膜疣表现出均匀、一致的标记，而另一些则显示糖缀合物的不对称、异质分布。
本研究表明，在所检查的所有硬性和软性玻璃膜疣类别中都存在含有特定碳水化合物残基的糖缀合物。硬性和软性玻璃膜疣被相同凝集素结合的观察结果表明它们在组成上可能相关。本研究中显示的与玻璃膜疣相关的糖缀合物的鉴定将有助于玻璃膜疣发生及其在年龄相关性黄斑病变发病机制中作用的研究。它们也可能为开发治疗干预途径提供基础。
