Phongphaew Wallaya, Wongsali Charuwan, Boonyakong Thanisorn, Samritwatchasai Theerawat, Chimnoi Wissanuwat, Kamyingkird Ketsarin
Department of Pathology, Faculty of Veterinary Medicine, Kasetsart University, Lad Yao, Chatuchak, Bangkok 10900, Thailand.
Veterinary Diagnostic Center, Faculty of Veterinary Medicine, Kasetsart University, Lad Yao, Chatuchak, Bangkok 10900, Thailand.
Vet World. 2023 May;16(5):1008-1017. doi: 10.14202/vetworld.2023.1008-1017. Epub 2023 May 13.
is a blood and tissue protozoan parasite affecting domestic and wild animals. The Thai strain, namely, from dairy cattle number 953 (TEDC 953) strain, has been successfully isolated from dairy cattle and cultivated . The -cultivated parasite is useful for biological studies, evaluation of novel chemotherapeutic agents, and production of antigens for diagnostic tests. This study aimed to observe the histopathology and virulence of an -adapted TEDC 953 strain .
The histopathology and virulence of the TEDC 953 strain were clarified in mice. Six mice were infected with 1 × 10 trypomastigotes of TEDC 953 strain intraperitoneally, and four mice were in the negative control. Parasitemia was monitored daily, and the mice were euthanized on 30 days post-infection (DPI). Internal organs were collected for histopathological examination using hematoxylin and eosin staining.
Histopathological lesions were found in the liver, lung, heart, kidney, spleen, and brain of the inoculated mice. The main histopathological feature was lymphoplasmacytic inflammation in parenchyma and perivascular areas of multiple organs, and the severity of histopathological changes was related to the presence of trypomastigotes in the regional vessels. Granulomatous inflammation was seen in meninges, pleura, renal capsule, renal pelvis, and spleen of some infected mice. Four mice died at 17, 24, 26, and 27 DPI with an average parasitemia of 4.05 × 10 trypomastigotes/mL. The average survival time was 23.5 DPI (mice = 4).
This study confirmed that the TEDC 953 strain is infectious and pathogenic in mice after the continuously cultivated . To replace the use of experimental animals, the -cultivated parasite can be used instead in further studies.
是一种影响家畜和野生动物的血液及组织原生动物寄生虫。泰国株，即来自953号奶牛的泰国家畜锥虫（TEDC 953）株，已成功从奶牛中分离并培养。培养的寄生虫可用于生物学研究、新型化疗药物的评估以及诊断测试抗原的生产。本研究旨在观察适应后的TEDC 953株的组织病理学和毒力。
在小鼠中明确TEDC 953株的组织病理学和毒力。6只小鼠腹腔内感染1×10个TEDC 953株的锥鞭毛体，4只小鼠作为阴性对照。每天监测寄生虫血症，感染后30天（dpi）对小鼠实施安乐死。收集内脏器官，用苏木精和伊红染色进行组织病理学检查。
在接种小鼠的肝脏、肺、心脏、肾脏、脾脏和大脑中发现组织病理学病变。主要组织病理学特征是多个器官实质和血管周围区域的淋巴细胞浆细胞性炎症，组织病理学变化的严重程度与局部血管中锥鞭毛体的存在有关。在一些感染小鼠的脑膜、胸膜、肾包膜、肾盂和脾脏中可见肉芽肿性炎症。4只小鼠分别在感染后17、24、26和27天死亡，平均寄生虫血症为4.05×10个锥鞭毛体/毫升。平均存活时间为23.5 dpi（小鼠 = 4）。
本研究证实，连续培养后的TEDC 953株在小鼠中具有传染性和致病性。为替代实验动物的使用，可在进一步研究中使用培养的寄生虫。
