Abdel-Hafez S K, Phillips S M, Zodda D M
Exp Parasitol. 1983 Apr;55(2):219-32. doi: 10.1016/0014-4894(83)90016-4.
An inhibition enzyme-linked immunosorbent assay (IELISA) was used to detect the presence of schistosome antigens obtained from cercariae, adult worms, and eggs of the parasite. Using appropriate titers of Schistosoma mansoni infected mouse serum (IMS), it was possible to detect less than 10 ng/ml of schistosome antigen when added to phosphate-buffered saline (PBS, pH 7.2) or normal human serum (NHS). The sensitivity of the test was highly contingent on the number of experimental variables including antibody titer and antigenic source. The results of specificity studies were complicated. Although there was no cross-reactivity detected with other unrelated antigen preparations, extensive cross-reactivity between various schistosome species and "stage-specific" antigens was observed. The IELISA, utilizing IMS, can quantitate the degree of antigenic cross-reactivity, i.e., genus-specific and cross-reacting antigenic determinants. Soluble egg antigen (SEA) preparations obtained from S. mansoni and S. japonicum actually "cross-reacted" more than cercarial- and egg-derived antigens obtained from the same species (S. mansoni). This test also showed a 32-fold increase in specificity for the quantitative detection of specific antigenic determinants when monoclonal antibodies were used to restrict the heterogeneity of the measured response. The technique proved satisfactory for the quantification of parasitic burden in mice and the detection of active infections in humans. Circulating antigen disappeared with a t 1/2 of 72-96 hr after successful treatment.
采用抑制酶联免疫吸附测定法（IELISA）检测从血吸虫尾蚴、成虫和虫卵中获得的血吸虫抗原。使用适当滴度的曼氏血吸虫感染小鼠血清（IMS），当将其添加到磷酸盐缓冲盐水（PBS，pH 7.2）或正常人血清（NHS）中时，能够检测到低于10 ng/ml的血吸虫抗原。该检测的灵敏度高度取决于包括抗体滴度和抗原来源在内的实验变量数量。特异性研究的结果较为复杂。虽然未检测到与其他无关抗原制剂的交叉反应，但观察到不同血吸虫种类和“阶段特异性”抗原之间存在广泛的交叉反应。利用IMS的IELISA能够定量抗原交叉反应的程度，即属特异性和交叉反应抗原决定簇。从曼氏血吸虫和日本血吸虫获得的可溶性虫卵抗原（SEA）制剂实际上比从同一物种（曼氏血吸虫）获得的尾蚴和虫卵衍生抗原的“交叉反应”更强。当使用单克隆抗体来限制测量反应的异质性时，该检测在定量检测特异性抗原决定簇方面的特异性提高了32倍。该技术被证明对于定量小鼠体内的寄生虫负荷和检测人类的活动性感染是令人满意的。成功治疗后，循环抗原以72 - 96小时的半衰期消失。
