Centro de Imunologia e Biologia Parasitária (CIBP), CSPGF, INSA Porto, Portugal.
Vet Parasitol. 2010 Apr 19;169(1-2):24-8. doi: 10.1016/j.vetpar.2009.12.025. Epub 2009 Dec 28.
Serotyping was previously described as a promising method for typing strains of Toxoplasma gondii. The majority of precedent studies utilized serum samples collected from human patients with different T. gondii-associated pathologies. The aim of this work was to study the applicability of the same procedure for serotyping naturally infected meat-producing animals. An ELISA test based on GRA6 and GRA7 C-terminal polymorphic peptides was used. Peptide GRA6II has polymorphisms specific for the archetypal strains type II, GRA6I/III for strains type I and III, GRA7I for strains type I and GRA7III for strains type III. As reference material, and to validate this approach, serum samples from eleven free-range chickens and fifteen pigs used for Toxoplasma genotypes isolation were selected. These strains integrate the Biological Resource Centre (BRC) ToxoBS Bank. Three serum samples from chickens and two from pigs had serotyping results in agreement with genotyping. Thirty-five serum samples from chickens, twenty-nine from pigs and fifty from sheep, seropositive for T. gondii, from which no isolate was obtained, were also serotyped. Serotype III appeared significantly more frequent among sheep. Our results show that serotyping still need refinement, but may become a valuable tool for typing Toxoplasma strains from animal origin.
血清分型曾被描述为一种对刚地弓形虫菌株进行分型的有前途的方法。大多数先前的研究都利用从患有不同弓形虫相关病理的人类患者中收集的血清样本。本研究旨在研究相同程序用于对自然感染的肉用动物进行血清分型的适用性。使用了基于 GRA6 和 GRA7 末端多态性肽的 ELISA 测试。肽 GRA6II 具有针对原型菌株 II 的特异性多态性，GRA6I/III 针对菌株 I 和 III，GRA7I 针对菌株 I 和 GRA7III 针对菌株 III。作为参考材料，并验证该方法，选择了 11 只散养鸡和 15 只用于分离弓形虫基因型的猪的血清样本。这些菌株整合了生物资源中心 (BRC) ToxoBS 银行。从三只鸡和两只猪的血清样本中得到的血清分型结果与基因分型一致。从 35 只鸡、29 只猪和 50 只绵羊中获得了血清阳性的 T. gondii 血清样本，但没有分离到菌株。绵羊中 III 型出现的频率明显更高。我们的结果表明，血清分型仍需进一步改进，但可能成为对动物源性弓形虫菌株进行分型的有价值的工具。
