Soto P, Parma A E
Laboratorio de Inmunoquimica-Facultad Ciencias Veterinarias-Universidad Nacional del Centro, Tandil, Argentina.
Vet Parasitol. 1989 Oct;33(3-4):343-8. doi: 10.1016/0304-4017(89)90143-x.
Holando-Argentina calves (males and females) were experimentally infected with Tritrichomonas foetus var. Belfast (T. foetus) by introducing 10(7) protozoa into the preputial and vaginal cavities, in order to analyse the course of the immune response to infection. Samples of serum, vaginal mucus and preputial secretion were taken periodically and assayed by means of microagglutination of living protozoa. The serum antibody titre, which averaged 32 before infection and was equivalent to titres in a non-infected group, increased to 512 in the heifers 11 weeks later and to 128 in the bulls 4 months post-infection. Agglutinating antibodies were not detected in the preputial cavity, but heifers showed antibodies in the vaginal mucus and became trichomoniasis free after 4 months. Conversely, genital secretions from the bulls gave rise to positive cultures during the whole period of experimentation. The intradermal sensitivity was checked using a soluble antigen from T. foetus. The diameter of the papula increased up to three times in heifers, while in bulls the results were no different than those from the non-infected group. Serum antibodies were of the IgG2 subclass, while those isolated from vaginal mucus were characterized as IgG1, an opsonizing antibody. Heifers were refractory to challenge infection after 1 year. The poor immune response in bulls is consistent with their role as carriers of T. foetus.
将10^7个原生动物接种到包皮腔和阴道腔，对荷兰-阿根廷犊牛（公母皆有）进行胎儿三毛滴虫贝尔法斯特变种（T. foetus）的实验性感染，以分析对感染的免疫反应过程。定期采集血清、阴道黏液和包皮分泌物样本，并通过活原生动物的微量凝集试验进行检测。感染前血清抗体滴度平均为32，与未感染组的滴度相当，11周后小母牛的抗体滴度升至512，感染后4个月公牛的抗体滴度升至128。在包皮腔中未检测到凝集抗体，但小母牛的阴道黏液中出现了抗体，4个月后不再感染滴虫。相反，在整个实验期间，公牛的生殖分泌物培养均呈阳性。使用来自T. foetus的可溶性抗原检查皮内敏感性。小母牛丘疹直径增大至原来的三倍，而公牛的结果与未感染组无异。血清抗体属于IgG2亚类，而从阴道黏液中分离出的抗体特征为IgG1，一种调理抗体。1年后小母牛对再次感染具有抵抗力。公牛免疫反应较差与其作为T. foetus携带者的角色相符。
