Kuo Y M, Bianco A E
Liverpool School of Tropical Medicine, United Kingdom.
Am J Trop Med Hyg. 1995 Dec;53(6):624-32. doi: 10.4269/ajtmh.1995.53.624.
Cattle experimentally infected with Onchocerca lienalis were examined by enzyme-linked immunosorbent assay and immunoblotting to determine the degree of stage- and species-specificity in the immune response to infection. Levels of serum antibodies to antigens derived from third-stage larvae increased little after the first three weeks of infection, and the range of antibody specificities remained limited following the appearance of microfilariae (mf) in the skin. In contrast, antibodies to antigens from adult worms of either sex exhibited a vigorous response, characterized by a series of peaks arising 15-30, 79, and > 266 days after infection that were coincident with the timings of larval molts and the onset of a patent infection. Antibody specificities to the adult worms included many directed to molecules that were shared with other life-cycle stages, but some were stage-specific and others were confined to one sex. A response cross-reactive with antigens from mf was initiated during the prepatent period, but antibody levels increased steeply after the infection became patent. This was followed by a major expansion of antibody specificities to products exclusively directed to mf, most notably in the range of 12-18 kilodaltons. Sera from O. lienalis-infected cattle cross-reacted extensively with antigens derived from O. volvulus adult worms and the profiles of antibody levels over time were indistinguishable from those obtained with O. lienalis extracts. The dominant response was of IgG1, although limited IgG2 and IgM reactivities were found, while no Onchocerca-specific IgA was detected. These results demonstrate that parasite development has a profound influence on the level and repertoire of antibodies produced during Onchocerca infections, and that extensive cross-reactivity exists between O. lienalis and O. volvulus, lending support to the role of cattle models in the study of human onchocerciasis.
通过酶联免疫吸附测定法和免疫印迹法对实验感染链尾盘尾丝虫的牛进行检测，以确定感染免疫反应中阶段和物种特异性的程度。感染前三周后，针对源自第三期幼虫的抗原的血清抗体水平几乎没有增加，并且在皮肤中出现微丝蚴（mf）后，抗体特异性范围仍然有限。相比之下，针对两性成虫抗原的抗体表现出强烈反应，其特征是在感染后15 - 30天、79天和> 266天出现一系列峰值，这些峰值与幼虫蜕皮时间和显性感染的开始时间一致。针对成虫的抗体特异性包括许多针对与其他生命周期阶段共有的分子，但有些是阶段特异性的，其他则局限于一种性别。在潜伏期开始了与mf抗原的交叉反应，但感染变为显性后抗体水平急剧上升。随后，抗体特异性主要扩展到专门针对mf的产物，最显著的是在12 - 18千道尔顿范围内。感染链尾盘尾丝虫的牛的血清与源自盘尾丝虫成虫的抗原广泛交叉反应，并且随着时间的推移抗体水平的变化曲线与用链尾盘尾丝虫提取物获得的曲线无法区分。主要反应是IgG1，尽管发现有限的IgG2和IgM反应性，而未检测到盘尾丝虫特异性IgA。这些结果表明，寄生虫发育对盘尾丝虫感染期间产生的抗体水平和种类有深远影响，并且链尾盘尾丝虫和盘尾丝虫之间存在广泛的交叉反应，这为牛模型在人类盘尾丝虫病研究中的作用提供了支持。
