Goff Arthur, Twenhafel Nancy, Garrison Aura, Mucker Eric, Lawler James, Paragas Jason
Virology Division, United States Army Medical Research Institute for Infectious Diseases, MD 21702-5011, USA.
Virus Res. 2007 Sep;128(1-2):88-98. doi: 10.1016/j.virusres.2007.04.014. Epub 2007 May 23.
Variola virus and other members of the genus Orthopoxviruses constitute a prominent bioterrorism and public health threat. Treatment with the anti-viral drug cidofovir inhibits replication of orthopoxviruses in vitro and in vivo. In this study, we visualized the effect of cidofovir on viral kinetics in orthopoxvirus infected mice by using whole-body fluorescence imaging (FI). We engineered a cowpox virus (CPV) expressing the enhanced green fluorescent protein (GFP). Single-step growth curves and calculated 50% lethal doses (LD(50)) of wild-type CPX (Wt-CPV) and GFP-expressing CPX (GFP-CPV) were comparable. Whole-body FI first detected GFP fluorescence in the mesenteric tissue of untreated animals on post-infection day (PID) 1. On PID 3 GFP signal was detected throughout the mesentery, in all abdominal organs by PID 5 and in most major organs, except for the heart and brain by PID 6. Infected animals treated with 25mg/kg of cidofovir also began showing signs of viral replication on PID 1, however, the fluorescent signal was limited only to discrete foci throughout the course of the infection. This work describes the first use of an established Orthopox model of infection to evaluate drug efficacy and track virus progression on a macroscopic level.
天花病毒和正痘病毒属的其他成员构成了重大的生物恐怖主义和公共卫生威胁。抗病毒药物西多福韦治疗可在体外和体内抑制正痘病毒的复制。在本研究中，我们通过全身荧光成像（FI）观察了西多福韦对正痘病毒感染小鼠病毒动力学的影响。我们构建了一种表达增强型绿色荧光蛋白（GFP）的牛痘病毒（CPV）。野生型CPX（Wt-CPV）和表达GFP的CPX（GFP-CPV）的单步生长曲线和计算出的50%致死剂量（LD50）相当。全身FI在感染后第1天（PID 1）首次在未治疗动物的肠系膜组织中检测到GFP荧光。在PID 3时，整个肠系膜均检测到GFP信号，在PID 5时所有腹部器官均检测到，在PID 6时除心脏和脑外的大多数主要器官均检测到。用25mg/kg西多福韦治疗的感染动物在PID 1时也开始出现病毒复制迹象，然而，在整个感染过程中荧光信号仅限于离散的病灶。这项工作描述了首次使用已建立的正痘病毒感染模型在宏观水平上评估药物疗效和追踪病毒进展情况。
