?d T Cells Provide Protective Function in Highly Pathogenic Avian H5N1 Influenza A Virus Infection

Dong, Peng; Ju, Xiangwu; Yan, Yiwu; Zhang, Siya; Cai, Menghua; Wang, Huaishan; Chen, Hui; Hu, Yu; Cui, Lianxian; Zhang, Jianmin; He, Wei

The animal experiments were conducted in the animal facility of the Institute of Basic Medical Sciences, Peking Union Medical College and the Institute of Military Veterinary Medicine, Academy of Military Medical Sciences, in accordance with governmental and institutional guidelines. Wild-type (WT) C57BL/6 mice were purchased from Vital River, a Charles River company in China. TCR-δ −/− mice were bred from B6.129P2-Tcrb tm1Mom /Tcrd tm1Mom mice provided by professor Mingzhao Zhu (Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences). All mice were housed in an SPF facility. Lung injury was induced via the intratracheal instillation of AF vehicle or virus as previously reported (21) . Briefly, WT and TCR-δ −/− mice were anesthetized by sodium pentobarbital and inoculated intranasally with 0.8 × 10 5 TCID 50 H5N1 virus. At 4 days post infection (DPI), mice were killed, and the lungs of each group of three mice were fixed in formalin and were then embedded in paraffin. Sections of 6 µm thickness were obtained and stained with hematoxylin-eosin. At 4 DPI, the wet weight of the lungs of three mice was measured. The lungs were then heated to 68 • C for 24 h, and the dry weight of the lungs was recorded; the wet/dry ratios were then calculated. The survival percentages and body weights in each group of 10 mice were monitored daily for 14 days. Survival data were analyzed by Kaplan-Meier survival analysis using GraphPad Prism 5 software.