【摘要】 本研究通过建立犬流感病毒（Canine influenza virus,CIV）感染BALB/c小鼠模型,探索新发现的甲流重组CIVs对小鼠的致病性。我们采用9株H1N1和1株H3N2甲流重组CIVs,以106 TCID₅₀/mL的剂量滴鼻攻毒10组小鼠。结果表明:感染后4 d小鼠体重均有一定程度的下降,其中A/Canine/Guangxi/LZ56/2015（H1N1）（简称LZ56）组的小鼠体重下降最为明显（P<0.5）,其存活率为77.78%;通过TCID₅₀测定发现10株甲流重组CIVs均能在小鼠的鼻窦和肺脏复制,以LZ56组的复制滴度最高,分别达到107.3 TCID₅₀/mL和10^5.3 TCID₅₀/mL;肺脏病理切片观察发现LZ36、LZ45、LZ56和QZ5组出现不同程度病变,以支气管上皮细胞坏死脱落,肺泡壁增厚,肺泡腔以及支气管内有大量的弥漫性浸润的单核细胞为主要特征。结果表明,新型重组CIVs均能感染BALB/c小鼠,并能在小鼠体内较好复制,甚至致死,一旦这些新型CIVs以犬为中间宿主传播给人,势必对人类健康构成重大威胁。因此,加强对CIVs的监测将为防控人流感大暴发提供提前预警。更多还原

【Abstract】 In the present study,we assessed the pathogenicity of novel emerging reassortant CIVs carrying pandemic/2009 segments in the mouse model.Mice were infected intranasally with 106 TCID₅₀/mL of 9 H1N1 and 1 H3N2 reassortant CIVs.Results showed that body weights of all mice decreased.Especially,mice infected with A/Canine/Guangxi/LZ56/2015（H1N1） lost more weights at 4 dpi and 77.78% of mice survived.Besides,these reassortant viruses replicated in turbinates and lungs.The virus titers of reached to 107.3 TCID₅₀/mL in turbanates and 105.3 TCID₅₀/mL in lungs.The pathological lesions were observed,characterized by necrosis of bronchial epithelials,thickness of alveolar septas and interstitial walls and diffuse infiltration of mononuclear cells.Taken together,our results showed that these reassortant CIVs with pandemic/2009 infected BALB/c mice and even caused death.更多还原