Oocyst-induced murine toxoplasmosis: Life cycle, pathogenicity, and stage conversion in mice fed Toxoplasma gondii oocysts
Oocyst-induced murine toxoplasmosis: Life cycle, pathogenicity, and stage conversion in mice fed Toxoplasma gondii oocysts
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DOI：
10.2307/3284282
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发表时间：
1997-10-01
影响因子：
1.3
通讯作者：
Blixt, JA
中科院分区：
文献类型：
--
作者：
Dubey, JP;Speer, CA;Blixt, JA
用1 ~ 7.5 × 10(7)个刚地弓形虫卵囊喂养小鼠，研究了孢子子向速殖子和慢殖子的发育。接种后2小时内，孢子体脱落并穿透小肠上皮。2 HAI时，大多数孢子子位于回肠表面上皮细胞和固有层内，8 HAI时，在肠系膜淋巴结也可见弓形虫。12 HAI时，子孢子在小肠固有层分裂为2个速殖子。到45个HAI时，喂食7.5 × 10(7)个卵囊的小鼠肠道和肠系膜淋巴结内出现大量速殖子生长。接种后4天，寄生虫已通过血液和淋巴向其他器官播散。刚地弓形虫首次从外周血中分离得到。脑组织8 DAI可见组织囊肿。通过抗慢闪子特异性（BAG-5抗原）血清免疫组化染色，BAG-5阳性生物首先出现在肠的5 DAI和脑的8 DAI。使用猫的生物测定法，首先在6至7 DAI之间的小鼠组织中检测到慢殖子，并且在大脑中发现它们之前在肠道中发现它们。喂食含有慢殖子的小鼠组织的猫在其粪便中出现卵囊的时间很短（< 10天），而喂食含有快殖子组织的猫在3周内没有出现卵囊。使用胃蛋白酶消化程序和小鼠生物测定，在第7 DAI的脑组织和第51和151 DAI的小鼠的许多器官中首次检测到慢殖子。在87和236 DAI时，在小鼠大脑中可见单个慢殖子、大小组织囊肿和速殖子。
The development of sporozoites to tachyzoites and bradyzoites was studied in mice after feeding 1-7.5 X 10(7) Toxoplasma gondii oocysts. Within 2 hr after inoculation (HAI), sporozoites had excysted and penetrated the small intestinal epithelium. At 2 HAI, most sporozoites were in surface epithelial cells and in the lamina propria of the ileum, and by 8 HAI, T. gondii was also seen in mesenteric lymph nodes. At 12 HAI, sporozoites had divided into 2 tachyzoites in the lamina propria of the small intestine. By 45 HAI, there was a profuse growth of tachyzoites in the intestine and mesenteric lymph nodes of mice fed 7.5 X 10(7) oocysts. Parasites had disseminated via the blood and lymph to other organs by 4 days after inoculation (DAI). Toxoplasma gondii was first isolated from peripheral blood at 4 HAI. Tissue cysts were visible histologically in the brain at 8 DAI. By using immunohistochemical staining with anti-bradyzoite-specific (BAG-5 antigen) serum, BAG-5-positive organisms were first seen at 5 DAI in the intestine and at 8 DAI in the brain. Using the bioassay in cats, bradyzoites were first detected in mouse tissues between 6 and 7 DAI, and they were found in intestines before they were found in the brain. Cats fed murine tissues containing bradyzoites shed oocysts in their feces with a short (< 10 days) prepatent period, whereas cats fed tissues containing tachyzoites did not shed oocysts within 3 wk. Using a pepsin-digestion procedure and mouse bioassay, bradyzoites were first detected in brain tissue at 7 DAI and in many organs of mice at 51 and 151 DAI. Individual bradyzoites, small and large tissue cysts, and tachyzoites were seen in the brains of mice at 87 and 236 DAI.