Waree Phuangphet, Ferguson David J P, Pongponratn Emsri, Chaisri Urai, Sukthana Yaowalark
Department of Protozoology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
Southeast Asian J Trop Med Public Health. 2007 Mar;38(2):223-31.
Acute and chronic Toxoplasma infections were evaluated in mice using stage specific antibodies and immunocytochemistry. Mice with acute toxoplasmosis were less active, had erectile body hair and seldom took food or water resulting in weight loss. All mice died within 7 days post-inoculation. The immunohistochemical technique enhanced visualization of parasites allowing their distribution to be accurately followed. Following intraperitoneal infection, tachyzoites were initially identified on the surface of the liver and spleen. There was a rapid increase in the number of tachyzoites associated with invasion from the surrounding connective tissue into the organs with formation of inflammatory lesions in the liver. The focal inflammatory lesions showed increasing numbers of tachyzoites with the period post-inoculation. Similar increases in tachyzoites were observed for the spleen. In contrast, only a few individual tachyzoites were seen in the brain at the final time point. In chronic infections, the mice were asymptomatic but tissue cysts containing large numbers of bradyzoites were observed in all brains with the average number of 295 tissue cysts per half brain and the average cystic size of 46.02 +/- 5.08 microm. By histology and immunostaining, the tissue cysts were readily identifiable along with a mild inflammatory cell infiltration into the meninges and perivascular cuffing. Double immunocytochemical labelling confirmed the exclusive presence of tachyzoites during the acute phase and bradyzoites during the chronic phase.
利用阶段特异性抗体和免疫细胞化学方法对小鼠的急性和慢性弓形虫感染进行了评估。患有急性弓形虫病的小鼠活动减少，体毛直立，很少进食或饮水，导致体重减轻。所有小鼠在接种后7天内死亡。免疫组织化学技术增强了寄生虫的可视化效果，使其分布得以准确追踪。腹腔感染后，速殖子最初在肝脏和脾脏表面被发现。随着速殖子数量的迅速增加，出现了从周围结缔组织侵入器官的情况，并在肝脏中形成了炎性病变。局灶性炎性病变中速殖子的数量随着接种后的时间而增加。脾脏中也观察到速殖子有类似的增加。相比之下，在最后时间点，在大脑中仅能看到少数单个速殖子。在慢性感染中，小鼠无症状，但在所有大脑中均观察到含有大量缓殖子的组织囊肿，每半个大脑中组织囊肿的平均数量为295个，囊肿平均大小为46.02±5.08微米。通过组织学和免疫染色，组织囊肿很容易识别，同时伴有轻度炎性细胞浸润到脑膜和血管周围形成套袖状。双重免疫细胞化学标记证实了急性期仅存在速殖子，慢性期仅存在缓殖子。
