Shared carbohydrate epitopes on distinct surface and secreted antigens of the parasitic nematode Toxocara canis.
Shared carbohydrate epitopes on distinct surface and secreted antigens of the parasitic nematode Toxocara canis.
复制标题
不同表面上共有的碳水化合物表位和寄生线虫犬弓蛔虫的分泌抗原。
DOI：
10.4049/jimmunol.139.1.207
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发表时间：
1987
影响因子：
4.4
通讯作者：
H. Smith
中科院分区：
文献类型：
--
作者：
R. Maizels;M. Kennedy;M. Meghji;B. Robertson;H. Smith
线虫寄生虫犬弓蛔虫存在于所有犬种中，对人类的健康危害不明确。我们已经研究了排泄分泌抗原（ES）和表面抗原的感染幼虫阶段，这是组织入侵哺乳动物宿主。用一组在小鼠中产生的针对整个ES的八种单克隆抗体探测抗原。八种抗体中有六种与ES分子上的高碘酸盐敏感的碳水化合物表位反应，其余两种（Tcn-3和Tcn-6）识别肽或高碘酸盐抗性糖决定簇。通过免疫沉淀和免疫印迹，抗碳水化合物单克隆抗体各自与几种不同的ES分子反应，这些ES分子从先前发表的工作中已知具有对比的生化特性。TCN-3和TCN-6主要针对32，000和120，000兆瓦。分子，分别。相似分子量的碘化表面抗原。在去污剂溶解后，通过每种抗体沉淀，但只有两个克隆（Tcn-2和-8）能够结合完整弓首线虫幼虫上表皮上的暴露位点。值得注意的是，这些抗体不与新孵化的幼虫结合，并且它们的靶抗原在体外培养的第二天之前表达很差。通过放射性标记单克隆结合的冷抗体抑制和双位点结合试验矩阵进一步研究了单克隆抗体的特异性。这些数据表明，Tcn-2、-4、-5和-8识别一组相关的重复糖表位，而Tcn-1、-6和-7结合相同分子上的离散决定簇。这些研究正在继续进行，以进一步确定抗原性弓蛔虫碳水化合物的结构，并比较碳水化合物和肽抗原的诊断效用。
The nematode parasite Toxocara canis is found in all dog populations and poses a poorly defined health hazard to humans. We have studied excretory-secretory antigen (ES) and surface antigens of the infective larval stage which is tissue-invasive in mammalian hosts. Antigens were probed with a panel of eight monoclonal antibodies raised in mice to whole ES. Six of eight antibodies reacted with periodate-sensitive carbohydrate epitopes on ES molecules, and the remaining two (Tcn-3 and Tcn-6) recognized either peptide or periodate-resistant sugar determinants. By immunoprecipitation and immunoblotting, the anti-carbohydrate monoclonals each reacted with several distinct ES molecules, known from previously published work to possess contrasting biochemical properties. Tcn-3 and -6 were directed predominantly against 32,000 and 120,000 m.w. molecules, respectively. Iodinated surface antigens of similar m.w. were precipitated by each antibody after detergent solubilization, but only two clones (Tcn-2 and -8) were able to bind exposed sites on the epicuticle of intact Toxocara larvae. Significantly, these antibodies do not bind to newly hatched larvae, and their target antigens are poorly expressed until the second day of in vitro cultivation. The specificities of the monoclonals were further studied by cold antibody inhibition of radiolabeled monoclonal binding, and by a matrix of two-site binding assays. These data show that Tcn-2, -4, -5, and -8 recognize a related group of repetitive carbohydrate epitopes, whereas Tcn-1, -6, and -7 bind discrete determinants on the same molecules. These studies are being continued to define further the structure of antigenic Toxocara carbohydrates and to compare the diagnostic utility of carbohydrate and peptide antigens.