摘要
目的 TLR3介导的天然免疫通路是抗感染重要的天然免疫机制,本文研究鼻感染烟曲霉菌是否能激活小鼠肺组织TLR3天然免疫信号通路。方法小鼠分正常组和感染组,感染组经鼻感染烟曲霉菌孢子,正常组经鼻滴入等量的生理盐水,8 h、24 h和48 h后处死小鼠,分离肺组织,取100 mg肺组织RT-PCR检测TLR3、TRIF及IFN-βmRNA水平、Western blot检测胞核IRF3的含量。取24 h、48 h和72 h小鼠肺组织制作病理切片,100 mg肺组织碾碎接种蔡氏培养基平板以检测肺组织烟曲霉菌载荷。结果感染组小鼠肺组织烟曲霉菌负荷72 h时显著下降,正常组烟曲霉菌培养阴性;正常组小鼠肺组织结构正常,感染组小鼠24 h时肺组织可见严重的炎症反应及出血,72 h时肺组织炎症反应减轻;RT-PCR及Western blot结果显示:感染组小鼠肺组织各时相点TLR3 mRNA、TRIF mRNA、IRF3和IFN-βmRNA的表达量均显著高于正常对照组(P<0.05),均在24 h达到最高峰(P<0.05)。结论烟曲霉菌感染的小鼠肺组织中TLR3信号通路得以激活,其介导的天然免疫对感染烟曲霉菌的清除和保护小鼠肺组织起了一定的作用。
The signal pathway mediated by TLR3 is an important mechanism in innate immunity against infection. This study aimed to investigate whether intranasal infection of Aspergillus fumigatus could activate TLR3-mediated innate immune signal pathway in lung tissue in mice. Mice were randomly divided into 2 groups： normal control and infection group. The mice of infection group were infected with conidia of Aspergillus fumigatus intranasally, and the mice were sacrificed at 8 h, 24 h and 48 h post infection for collection of lung tissue. The TLR3, TRIF and IFN-β mRNA levels were detected by RT-PCR, and the nucleus IRF3 level in 100 mg lung tissues of each mouse were detected by Western blot. The lung tissue collected at 24 h, 48 h and 72 h post- infection were used for pathological study and detection of Aspergillus fumigatus burden. We found that cultivation of Aspergillusfumigatus was negative in control group, while in infection group the amount of AspergiUusfumigatus colonies at 72 h were significantly less than ones at 24 h and 48 h （P〈 0.05）. Severe inflammation and bleeding were observed at 24 h post-infection and inflammation was relieved significantly at 72 h in lung tissue in the infection group. The results of RT-PCR and Western blot showed that TLR3 mRNA, TRIF mRNA, IRF3 and IFN-β mRNA levels at all three time points in infection group were significantly higher than ones in control group （P〈 0.05）, and the expression level of the proteins peaked at 24 h （P〈 0.05）. We concluded that TLR3 signal pathway was activated in lung of mice infected with Aspergillus fumigatus. The innate immunity mediated by TLR3 plays partial roles in clearance of A spergillus fumigatus and protection of lung tissues of infected mice.
出处
《免疫学杂志》
CAS
CSCD
北大核心
2013年第11期948-952,共5页
Immunological Journal
基金
国家自然科学基金(30760236)
江西省自然科学基金(2009GZY0184)
