McGregor Alistair, Choi K Yeon, Cui Xiaohong, McVoy Michael A, Schleiss Mark R
Division of Pediatric Infectious Diseases, University of Minnesota Medical School, Center for Infectious Diseases and Microbiology Translational Research, 2001 6th Street SE, Minneapolis, MN 55455, United States.
Antiviral Res. 2008 Jun;78(3):250-9. doi: 10.1016/j.antiviral.2008.01.008. Epub 2008 Feb 14.
In lieu of a licensed vaccine, antivirals are being considered as an intervention to prevent congenital human cytomegalovirus (HCMV) infection. Ideally, antiviral therapies should undergo pre-clinical evaluation in an animal model prior to human use. Guinea pig cytomegalovirus (GPCMV) is the only small animal model for congenital CMV. However, GPCMV is not susceptible to the most commonly used HCMV antiviral, ganciclovir (GCV), rendering in vivo study of this agent problematic in the guinea pig model. Human cytomegalovirus (HCMV) susceptibility to GCV is linked to the UL97 gene. We hypothesized that GPCMV susceptibility to GCV could be improved by inserting the HCMV (Towne) UL97 gene into the GPCMV genome in place of the homolog, GP97. A chimeric GPCMV (GPCMV::UL97) expressed UL97 protein, and replicated efficiently in cell culture, with kinetics similar to wild-type GPCMV. In contrast, deletion of GP97 resulted in a virus (GPCMVdGP97) that grew poorly in culture. GPCMV::UL97 had substantially improved susceptibility to the inhibitory effects of GCV in comparison to wild-type GPCMV. Additionally, GPCMV::UL97 exhibited improved susceptibility to another antiviral undergoing clinical trials, maribavir (MBV; benzimidazole riboside 1263W94), which also acts through UL97.
作为一种替代许可疫苗的手段，抗病毒药物正被视为预防先天性人巨细胞病毒（HCMV）感染的一种干预措施。理想情况下，抗病毒疗法在用于人体之前应在动物模型中进行临床前评估。豚鼠巨细胞病毒（GPCMV）是先天性巨细胞病毒唯一的小动物模型。然而，GPCMV对最常用的HCMV抗病毒药物更昔洛韦（GCV）不敏感，这使得在豚鼠模型中对该药物进行体内研究存在问题。人巨细胞病毒（HCMV）对GCV的敏感性与UL97基因有关。我们假设，通过将HCMV（Towne株）UL97基因插入GPCMV基因组中取代同源物GP97，可以提高GPCMV对GCV的敏感性。一种嵌合GPCMV（GPCMV::UL97）表达UL97蛋白，并在细胞培养中高效复制，其动力学与野生型GPCMV相似。相比之下，GP97的缺失导致一种病毒（GPCMVdGP97）在培养中生长不佳。与野生型GPCMV相比，GPCMV::UL97对GCV抑制作用的敏感性有了显著提高。此外，GPCMV::UL97对另一种正在进行临床试验的抗病毒药物马立巴韦（MBV；苯并咪唑核苷1263W94）的敏感性也有所提高，该药物也是通过UL97发挥作用的。
