Oka S, Shigeta S, Ono K, Jyo T
J Allergy Clin Immunol. 1987 Jul;80(1):57-63. doi: 10.1016/s0091-6749(87)80191-4.
O-Glycosidically linked oligosaccharides (Gp-1 beta-b) were liberated from a large size glycopeptide (GP) fraction (Gp-1) in a Pronase digest of a sea squirt antigen termed Gi-rep by the treatment with 0.1 N NaOH per 1 mol/L of NaBH4. Gp-1 beta-b as well as Gp-1 and the intact antigen was capable of inducing a remarkable erythema in the skin of patients with asthma with sea squirt allergy at its concentration of 10 micrograms/ml. N-Glycoside GP fractions (Gp-1 beta-a and Gp-2 beta) having the allergenic activity were also prepared as alkali-resistant GPs from Gp-1 and the other relatively small size GP fraction (Gp-2) of the Pronase digest, respectively, after the alkali treatment. Chemically, the three allergenically active preparations were rich in galactosamine, glucosamine, and fucose in common, although the N-linked carbohydrates were much larger in size than O-linked carbohydrates. Accordingly, it has been expected that the epitope of the sea squirt antigen corresponds to certain oligosaccharide units residing in both of the O- and N-linked carbohydrate chains of the antigen. This suggestion was consistent with the observation that the allergenic activity of Gi-rep was significantly unstable to the periodate oxidation but substantially stable not only to acid, alkali, and heat treatments but also to the enzymatic proteolysis with Pronase E.
通过每1摩尔/升硼氢化钠用0.1N氢氧化钠处理，从一种被称为Gi-rep的海鞘抗原的链霉蛋白酶消化物中的大尺寸糖肽（GP）部分（Gp-1）中释放出O-糖苷键连接的寡糖（Gp-1β-b）。Gp-1β-b以及Gp-1和完整抗原在浓度为10微克/毫升时，能够在对海鞘过敏的哮喘患者皮肤中引起显著的红斑。具有致敏活性的N-糖苷GP部分（Gp-1β-a和Gp-2β）也分别在碱处理后，从链霉蛋白酶消化物的Gp-1和另一个相对小尺寸的GP部分（Gp-2）中作为耐碱GP制备。从化学角度来看，这三种具有致敏活性的制剂共同富含半乳糖胺、葡萄糖胺和岩藻糖，尽管N-连接的碳水化合物在大小上比O-连接的碳水化合物大得多。因此，预计海鞘抗原的表位对应于存在于抗原的O-和N-连接碳水化合物链中的某些寡糖单元。这一建议与以下观察结果一致：Gi-rep的致敏活性对高碘酸盐氧化显著不稳定，但对酸、碱和热处理以及对链霉蛋白酶E的酶促蛋白水解基本上稳定。
