为建立稳定、可靠的Ⅱd亚型微小隐孢子虫感染的小鼠模型,本研究以1×10^(6)个/只剂量的Ⅱd亚型微小隐孢子虫卵囊感染3周龄雌性昆明小鼠,对感染前后小鼠粪便样品进行显微镜观察和隐孢子18S r RNA和GP60基因的套式PCR检测、以及对小...为建立稳定、可靠的Ⅱd亚型微小隐孢子虫感染的小鼠模型,本研究以1×10^(6)个/只剂量的Ⅱd亚型微小隐孢子虫卵囊感染3周龄雌性昆明小鼠,对感染前后小鼠粪便样品进行显微镜观察和隐孢子18S r RNA和GP60基因的套式PCR检测、以及对小鼠的排卵囊规律、临床症状变化、体质量变化、回肠组织病变特征和回肠绒毛指数进行分析。结果显示:通过形态学和PCR方法均能在粪便样品中检测到微小隐孢子虫;感染组小鼠较对照组在排卵囊高峰期体质量的增加略微减少,但总体增加趋势一致,在排卵囊高峰期时感染组小鼠饮水量减少、反应迟钝、粪便变稀,高峰期后小鼠精神状态逐渐恢复良好;通过对感染后7 d小鼠的回肠组织制备病理切片并经HE染色后观察发现,与对照组相比,感染组小鼠回肠组织中出现微小隐孢子虫附着,部分区域杯状细胞数量减少,上皮细胞排列轻微紊乱且部分脱落,黏膜层可见少量炎症细胞;回肠绒毛长度显著变短、变钝,隐窝深度变浅,但绒毛直径和黏膜厚度未见显著变化。上述结果与动物临床感染隐孢子虫的症状、病理变化等基本一致,表明本研究首次建立了Ⅱd亚型微小隐孢子虫感染昆明小鼠的模型。本研究该模型的建立为研究微小隐孢子虫的致病性、宿主的免疫调节机制以及药物和疫苗的筛选提供研究基础。展开更多
In order to determine the effect of foreign genes on a transgenic parasite,the pathogenicity and development in chickens of transgenic E.tenella strain TE1,which expresses yellow fluorescent protein (YFP) and dihydrof...In order to determine the effect of foreign genes on a transgenic parasite,the pathogenicity and development in chickens of transgenic E.tenella strain TE1,which expresses yellow fluorescent protein (YFP) and dihydrofolate reductase thymidylate synthase derived from Toxoplasma gondii(TgDHFR-TS), were compared with that of the parental strain BJ.Results indicated that the fecundity of the transgenic parasite(TE1) was reduced at least 4 times relative to that of the BJ strain.Low dosage of the TE1 strain induced less pathogenesis in chickens than did the BJ strain,but chickens inoculated with a higher dosage of TE1 oocysts displayed severe pathogenicity and mortality as did the BJ strain.In addition,trophozoites, the first generation and the second generation meronts and merozoites,microgamonts and macrogamonts of the transgenic parasite TE1 were seen by fluorescence microscopy.More interestingly,not all four sporonts in the sporulating transgenic oocysts express YFP.These findings suggest that the expression of YFP and TgDHFR-TS genes to some extent reduced pathogenicity and reproductive potential of transgenic E.tenella.Recombination between homologous or non-homologous chromosomes occurred during zygotic meiosis in E.tenella strain TE1.展开更多
文摘为建立稳定、可靠的Ⅱd亚型微小隐孢子虫感染的小鼠模型,本研究以1×10^(6)个/只剂量的Ⅱd亚型微小隐孢子虫卵囊感染3周龄雌性昆明小鼠,对感染前后小鼠粪便样品进行显微镜观察和隐孢子18S r RNA和GP60基因的套式PCR检测、以及对小鼠的排卵囊规律、临床症状变化、体质量变化、回肠组织病变特征和回肠绒毛指数进行分析。结果显示:通过形态学和PCR方法均能在粪便样品中检测到微小隐孢子虫;感染组小鼠较对照组在排卵囊高峰期体质量的增加略微减少,但总体增加趋势一致,在排卵囊高峰期时感染组小鼠饮水量减少、反应迟钝、粪便变稀,高峰期后小鼠精神状态逐渐恢复良好;通过对感染后7 d小鼠的回肠组织制备病理切片并经HE染色后观察发现,与对照组相比,感染组小鼠回肠组织中出现微小隐孢子虫附着,部分区域杯状细胞数量减少,上皮细胞排列轻微紊乱且部分脱落,黏膜层可见少量炎症细胞;回肠绒毛长度显著变短、变钝,隐窝深度变浅,但绒毛直径和黏膜厚度未见显著变化。上述结果与动物临床感染隐孢子虫的症状、病理变化等基本一致,表明本研究首次建立了Ⅱd亚型微小隐孢子虫感染昆明小鼠的模型。本研究该模型的建立为研究微小隐孢子虫的致病性、宿主的免疫调节机制以及药物和疫苗的筛选提供研究基础。
基金supported by the National High Technology Research and Development Program of China(Project No. 2006AA02Z458)the Doctor Startup Foundation of Henan University of Science and Technology(09001350)
文摘In order to determine the effect of foreign genes on a transgenic parasite,the pathogenicity and development in chickens of transgenic E.tenella strain TE1,which expresses yellow fluorescent protein (YFP) and dihydrofolate reductase thymidylate synthase derived from Toxoplasma gondii(TgDHFR-TS), were compared with that of the parental strain BJ.Results indicated that the fecundity of the transgenic parasite(TE1) was reduced at least 4 times relative to that of the BJ strain.Low dosage of the TE1 strain induced less pathogenesis in chickens than did the BJ strain,but chickens inoculated with a higher dosage of TE1 oocysts displayed severe pathogenicity and mortality as did the BJ strain.In addition,trophozoites, the first generation and the second generation meronts and merozoites,microgamonts and macrogamonts of the transgenic parasite TE1 were seen by fluorescence microscopy.More interestingly,not all four sporonts in the sporulating transgenic oocysts express YFP.These findings suggest that the expression of YFP and TgDHFR-TS genes to some extent reduced pathogenicity and reproductive potential of transgenic E.tenella.Recombination between homologous or non-homologous chromosomes occurred during zygotic meiosis in E.tenella strain TE1.
