Weber A, Schröder H, Thalberg K, März L
Institut für Chemie, Universität für Bodenkultur, Vienna, Austria.
Allergy. 1987 Aug;42(6):464-70. doi: 10.1111/j.1398-9995.1987.tb00364.x.
Phospholipase A2 (E.C. 3.1.1.4.) is a major allergen of honey bee venom. It exists in a glycosylated and an unglycosylated variant. Both forms and the glycopeptide isolated after exhaustive proteolytic digestion were tested in RAST and RAST inhibition studies. IgE from 11 of 14 bee venom allergy sera exhibited significantly higher, and in two cases exclusive, affinity towards glycosylated phospholipase. In RAST inhibition experiments using phospholipase coupled to discs five of the sera were completely inhibited by glycopeptide at 0.1 mg/ml; four sera were partially inhibited and two sera could not be inhibited. Glycoasparagine, lacking all amino acids except the carbohydrate-linking asparagine, inhibits IgE-binding to glycopeptide discs up to 100%. These data clearly demonstrate that an oligosaccharide of a structural type frequently found in glycoproteins can represent an epitope which is recognized by IgE antibodies from allergic patients, which are specifically directed against the parent glycoprotein.
磷脂酶A2（E.C. 3.1.1.4.）是蜜蜂毒液的主要过敏原。它以糖基化和非糖基化变体形式存在。在放射变应原吸附试验（RAST）和RAST抑制研究中对这两种形式以及经彻底蛋白水解消化后分离出的糖肽进行了测试。14份蜜蜂毒液过敏血清中的11份的免疫球蛋白E（IgE）对糖基化磷脂酶表现出显著更高的亲和力，在两例中则表现出排他性亲和力。在使用与圆盘偶联的磷脂酶进行的RAST抑制实验中，5份血清在糖肽浓度为0.1 mg/ml时被完全抑制；4份血清被部分抑制，2份血清未被抑制。除了连接碳水化合物的天冬酰胺外不含所有氨基酸的糖天冬酰胺，可100%抑制IgE与糖肽圆盘的结合。这些数据清楚地表明，糖蛋白中常见的一种结构类型的寡糖可以代表一个表位，该表位可被来自过敏患者的IgE抗体识别，这些抗体是特异性针对母体糖蛋白的。
