Dunne D W, Butterworth A E, Fulford A J, Kariuki H C, Langley J G, Ouma J H, Capron A, Pierce R J, Sturrock R F
Department of Pathology, University of Cambridge, GB.
Eur J Immunol. 1992 Jun;22(6):1483-94. doi: 10.1002/eji.1830220622.
Previous studies in school children have demonstrated the slow development with age of resistance to reinfection after chemotherapy of Schistosoma mansoni infections, and have indicated that inappropriate ("blocking") antibody responses prevent the expression of immunity in young children. The present study was designed to investigate further the nature of the protective responses, by serological studies on a group of 151 S. mansoni-infected individuals resident in an endemic area in Machakos District, Kenya. Antibody levels against various antigens in blood samples before treatment were related to intensity of previous infections; antibodies in blood samples taken 6 months after treatment were related to cumulative reinfection rates over the following 30 months. IgE against an adult-worm antigen preparation correlated positively with age and negatively with reinfection. In contrast, IgE antibodies against other life-cycle stages showed either no relationship or the reverse correlation. Furthermore, antibodies of other isotypes against adult-worm antigens showed no correlations with reinfection. The correlation with IgE could be demonstrated for different preparations of adult worms, including a periodate-treated preparation presumptively depleted of carbohydrate epitopes. For both the intact and the periodate-treated preparations, multiple regression analysis of the results for children less than or equal to 16 years old demonstrated an IgE effect after allowing for age, although this effect was not observed in a previously studied group of school children. Western blot analysis of the adult-worm preparation revealed a limited set of antigens recognized by IgE, among which an antigen of 22 kDa was prominent. The qualitative presence of IgE against this antigen could also be shown to be related to a lack of subsequent reinfection.
以往对学童的研究表明，曼氏血吸虫感染化疗后，抵抗再感染的能力随年龄增长而缓慢发展，且表明不适当的（“阻断”）抗体反应会阻碍幼儿免疫力的表达。本研究旨在通过对肯尼亚马查科斯区一个流行地区居住的151名曼氏血吸虫感染个体进行血清学研究，进一步探究保护性反应的本质。治疗前血样中针对各种抗原的抗体水平与既往感染强度相关；治疗6个月后采集的血样中的抗体与随后30个月内的累积再感染率相关。针对成虫抗原制剂的IgE与年龄呈正相关，与再感染呈负相关。相比之下，针对其他生命周期阶段的IgE抗体要么无相关性，要么呈相反的相关性。此外，针对成虫抗原的其他同种型抗体与再感染无相关性。针对不同的成虫制剂，包括经高碘酸盐处理、推测已去除碳水化合物表位的制剂，均可证明与IgE的相关性。对于完整制剂和经高碘酸盐处理的制剂，对16岁及以下儿童的结果进行多元回归分析表明，在考虑年龄因素后存在IgE效应，尽管在先前研究的一组学童中未观察到这种效应。对成虫制剂的蛋白质印迹分析显示，IgE识别的抗原种类有限，其中一种22 kDa的抗原尤为突出。针对该抗原的IgE的定性存在也与随后无再感染相关。
