Chandrashekar R, Ogunrinade A F, Henry R W, Lustigman S, Weil G J
Department of Medicine, Washington University Medical Center, St. Louis, Missouri.
Exp Parasitol. 1993 Sep;77(2):224-34. doi: 10.1006/expr.1993.1079.
Improved methods for diagnosis of onchocerciasis are needed. We have recently identified immune complex-associated parasite antigens in sera from onchocerciasis patients. The goal of this study was to produce monoclonal antibodies to these antigens that might be used in antigen detection assays. Two monoclonal antibodies (OV-1 and OV-5) that bind to parasite antigens in immunoblots of PEG-precipitated immune complexes from human onchocerciasis sera and to corresponding antigens in adult worm extracts and excretory-secretory products were produced. The target epitopes of the monoclonals are heat stable, resistant to trypsin, and destroyed by Pronase. The two monoclonals produce similar but not identical patterns of binding to immunoblots of Onchocerca volvulus adult worm antigen with major bands at 43-47, 58-63, and 70 kDa. OV-1 and OV-5 appear to bind to two distinct but closely related epitopes, neither of which is phosphorylcholine. Immunoelectron microscopy showed that the epitopes recognized by these monoclonals are widely distributed in adult female worms, but concentrated in the uterus and intestine. Antigen assays based on these antibodies detected parasite antigen in 9 of 14 sera from onchocerciasis patients, but significant background signal was detected in some nonendemic human sera. Thus, although this study has provided new information on parasite antigens in sera from onchocerciasis patients, additional work will be needed to achieve the goal of producing a sensitive and specific antigen diagnostic test for onchocerciasis.
需要改进盘尾丝虫病的诊断方法。我们最近在盘尾丝虫病患者的血清中鉴定出了与免疫复合物相关的寄生虫抗原。本研究的目的是制备针对这些抗原的单克隆抗体，这些抗体可用于抗原检测试验。我们制备了两种单克隆抗体（OV-1和OV-5），它们在来自人类盘尾丝虫病血清的聚乙二醇沉淀免疫复合物的免疫印迹中与寄生虫抗原结合，并与成虫提取物和排泄分泌产物中的相应抗原结合。单克隆抗体的靶表位对热稳定，对胰蛋白酶有抗性，且被链霉蛋白酶破坏。这两种单克隆抗体与盘尾丝虫成虫抗原免疫印迹的结合模式相似但不完全相同，主要条带位于43-47、58-63和70 kDa。OV-1和OV-5似乎与两个不同但密切相关的表位结合，这两个表位都不是磷酸胆碱。免疫电子显微镜显示，这些单克隆抗体识别的表位在成年雌虫中广泛分布，但集中在子宫和肠道。基于这些抗体的抗原检测法在14份盘尾丝虫病患者血清中的9份中检测到了寄生虫抗原，但在一些非流行地区的人类血清中检测到了显著的背景信号。因此，尽管本研究提供了关于盘尾丝虫病患者血清中寄生虫抗原的新信息，但仍需要进一步开展工作，以实现开发出一种灵敏且特异的盘尾丝虫病抗原诊断检测方法的目标。
