小鼠脑无症状性单纯疱疹病毒Ⅰ型感染的实验研究

Experimental study on the asymptomatic herpes simplex virus type one infection in the brain of mice

【目的】观察单纯疱疹病毒I型(herpes simplex virus-type one,HSV-1)是否可以引起脑组织的无症状性感染,探讨多发性硬化的发病机制。【方法】将Balb/c小鼠分为实验组、对照组和脑炎组,在不同时间点观察小鼠神经病学体征、行为学以及体重变化;用聚合酶链反应法检测三叉神经节病毒DNA片段;免疫荧光法检测脑组织疱疹病毒抗原表达,以判定脑组织病毒增殖性感染的存在。【结果】实验组小鼠各时相点神经病学体征、神经行为学和体重变化与对照组小鼠相比较差异无统计学意义。在病毒接种的各时相点,大部分小鼠三叉神经节检测到了疱疹病毒DNA片段,同时脑的颞叶、顶叶和额叶皮层均发现片状HSV抗原阳性表达神经元,以7 d组阳性细胞最多,荧光亮度最强,15 d组阳性细胞减少,荧光亮度减弱。【结论】单纯疱疹病毒Ⅰ型能够引发小鼠脑组织的急性、短暂性、无症状性非坏死性感染。

[ Objective] To investigate the possibility of asymptomatic infection of：Herpes simplex virus type- 1 （ HSV-1 ） in brain mice, for understanding more about the pathogenesis of multiple sclerosis （MS）. [ Methods] Balb/c mice were divided into three groups： experimental group, control group and encephalitis group. Changes of neurological symptom, behavior and weight of mice were observed at different time. Then DNA fragment of HSV in trigeminal nerve ganglion （TG） was detected by PCR, antigen in brain was detected by indirect-immunofluorescence to determine the occurrence of acute infection. [ Results] The scores of the neurological survey, behavioral tests and changes of body weights were statistically significant as compared to those of the controll group. DNA fragment in most of the TGs in mice and at the same time patches of HSV antigen positive neurons in the temporal lobe, parietal lobe, frontal lobe we detected. The number of the positive neurons were the most at the time of 7 d, then decreased at the time of 15 d, so did the fluorescence lightness of the neurons. [ Conclusions] HSV-1 can induce acute, instant, asymp- tomatic infection with no necrosis occurrence in brain in mice.