新孢子虫对小鼠致病力及在小鼠体内动态分布的研究

Virulence and Dynamic Distribution of Neospora caninum in Mice

小鼠是研究新孢子虫的动物模型.通过小鼠毒力试验,检测3株新孢子虫（Nc-1,Nc-LIV和Nc-BJ）对BALB/c小鼠的致病力差异;同时研究了低剂量Nc-LIV株（1＆#215;106）感染后,新孢子虫在小鼠的心、肝、脾、肺、肾、脑和后肢肌肉中的分布情况及其在血清中抗体的动态变化规律.结果显示,Nc-LIV对BALB/c小鼠的毒力最强,Nc-BJ其次,Nc-1最弱.小鼠血清中新孢子虫抗体在感染后4d出现至第32天达到峰值.感染后第8天在脑组织中可检测到新孢子虫特异性基因Nc-5,在第32天达到峰值后下降;其他组织中则分布很少.通过观察新孢子虫Nc-LIV在小鼠体内各器官组织动态分布的规律,为进一步建立小鼠感染新孢子虫的动物模型,研究新孢子虫病奠定了基础.

Mice are animal models in Neospora caninum research. Virulence of three strains of N. caninum （Nc-1, Nc-LIV and No-B J）was detected by virulence assay. Parasites distribution in tissues and dynamic variation of antibody were investigated when mice were infected with low doses of Nc-LIV （1×10^6）. Nc-LIV was the strongest virulence strain for BALB/c mice, Nc-BJ was the moderate virulence strain and Nc-1 was the weakest one. Serum antibodies to Neospora appeared in 4 days after infection and reached the peak in 32 days. N. caninum specific genes No-5 could be detected in the brains after 8 days and at the peak in 32 days after infection. Spread of tachyzoites of Nc-LIV among the tissues were traced in BALB/c mice for further establishment of an animal model and laid the foundation of the N. caninum research.