Long G W, Yogore M G, Lewert R M, Blas B L, Pelley R P
Am J Trop Med Hyg. 1982 Sep;31(5):1006-14. doi: 10.4269/ajtmh.1982.31.1006.
At present, there is no consensus that purified schistosome egg antigens offer any advantage in the diagnosis of schistosomiasis by enzyme linked immunosorbent assay (ELISA). Previously, we demonstrated by multiple techniques that the major serologic antigens in Schistosoma japonicum soluble egg antigen (SEA) are glycoproteins, and that the glycoproteins with highest specificity and sensitivity are hydrophobes. We therefore tested these materials for their specificity, sensitivity and cost effectiveness in the ELISA. In this study we used five SEA fractions that varied in their purity and antigenicity. The order of immunologic specific activity in the ELISA, measured by titration of a standard sera pool, was: hydrophobic glycoproteins (highest), crude SEA glycoproteins, hydrophilic glycoproteins, crude SEA, and SEA proteins (lowest). Complexity (purity) of these materials were (in rank order), hydrophilic glycoproteins (purest), hydrophobic glycoproteins, crude glycoproteins, SEA proteins, and crude SEA (most complex). Epidemiologic sensitivity in the ELISA was tested on limited but well characterized populations. At high antigen coating concentration (0.5 microgram/well), the only antigen fraction with poor sensitivity was SEA proteins. There was little difference in epidemiologic sensitivity between the purer fractions with highest immunologic sensitivity (hydrophobic glycoproteins and crude SEA glycoproteins) and the crude SEA which possesses intermediate immunologic sensitivity. Differences in epidemiologic sensitivity were most pronounced when wells were coated at an antigen concentration (0.1 microgram/well) where crude SEA began to fail. Specificity for all preparations, assessed by reactivity with sera from patients with other trematode infections and with cestode and nematode infections, was excellent. The clinical sensitivity of the ELISA employing crude S. japonicum SEA is so high, and the specificity so good, that the increased immunologic sensitivity of partially purified antigens had little effect on epidemiologic sensitivity. This is not true for the S. mansoni ELISA where crude antigens had inferior sensitivity and specificity.
目前，对于纯化的血吸虫卵抗原在酶联免疫吸附测定（ELISA）诊断血吸虫病中是否具有任何优势尚无共识。此前，我们通过多种技术证明，日本血吸虫可溶性卵抗原（SEA）中的主要血清学抗原是糖蛋白，并且具有最高特异性和敏感性的糖蛋白是疏水蛋白。因此，我们在ELISA中测试了这些物质的特异性、敏感性和成本效益。在本研究中，我们使用了五种纯度和抗原性不同的SEA组分。通过滴定标准血清池来测量ELISA中的免疫特异性活性顺序为：疏水糖蛋白（最高）、粗SEA糖蛋白、亲水糖蛋白、粗SEA和SEA蛋白（最低）。这些物质的复杂性（纯度）依次为（按顺序排列）：亲水糖蛋白（最纯）、疏水糖蛋白、粗糖蛋白、SEA蛋白和粗SEA（最复杂）。在有限但特征明确的人群中测试了ELISA中的流行病学敏感性。在高抗原包被浓度（0.5微克/孔）下，唯一敏感性较差的抗原组分是SEA蛋白。免疫敏感性最高的较纯组分（疏水糖蛋白和粗SEA糖蛋白）与具有中等免疫敏感性的粗SEA之间的流行病学敏感性差异不大。当以粗SEA开始失效的抗原浓度（0.1微克/孔）包被孔时，流行病学敏感性差异最为明显。通过与其他吸虫感染患者以及绦虫和线虫感染患者的血清反应性评估，所有制剂的特异性都非常好。使用粗日本血吸虫SEA的ELISA临床敏感性如此之高，特异性如此之好，以至于部分纯化抗原增加的免疫敏感性对流行病学敏感性影响很小。对于曼氏血吸虫ELISA来说并非如此，其粗抗原的敏感性和特异性较差。
