Greif G
Bayer, Animal Health, Institute of Parasitology, Leverkusen, Germany.
Parasitol Res. 2000 Oct;86(10):787-90. doi: 10.1007/s004360000218.
Some characteristics of immune sera after toltrazuril treatment which may be involved in the enhancement of immunity are as follows. Firstly, toltrazuril acts against all intracellular parasite stages from 1 to 168 h post-infection: intracellular schizonts of generations I, II and III and also intracellular gamonts. These damaged stages remain in the host cell for a prolonged time, during which they act as antigens which can be recognised by the immune system. Secondly, immune sera during therapeutic treatment with toltrazuril show a high antibody titre of 1:100 and 1:250 in IFAT after challenge. In the immunoblot, these sera show a strong reaction with low molecular protein fragments between 14 and 20 kDa. Toltrazuril does not interfere with the process of parasite protein recognition by the immune system during infection. Thirdly, there is a tendency for a higher IgG response after treatment with toltrazuril. Fourthly, a higher antibody titre in IFAT, immunoblot and ELISA correlates with a higher reduction in oocyst excretion, lesion scoring and increased weight gains in toltrazuril-treated animals.
托曲珠利治疗后免疫血清的一些可能与免疫增强有关的特征如下。首先，托曲珠利对感染后1至168小时内的所有细胞内寄生虫阶段均有作用：I代、II代和III代细胞内裂殖体以及细胞内配子体。这些受损阶段会在宿主细胞中停留较长时间，在此期间它们作为可被免疫系统识别的抗原。其次，托曲珠利治疗期间的免疫血清在攻击后间接荧光抗体试验（IFAT）中显示出1:100和1:250的高抗体滴度。在免疫印迹中，这些血清与14至20 kDa之间的低分子蛋白片段有强烈反应。托曲珠利在感染期间不干扰免疫系统对寄生虫蛋白的识别过程。第三，托曲珠利治疗后有更高的IgG反应趋势。第四，IFAT、免疫印迹和酶联免疫吸附测定（ELISA）中更高的抗体滴度与托曲珠利治疗动物的卵囊排泄减少、病变评分降低以及体重增加相关。
