Genetic Pathways of Human Cytomegalovirus Drug Resistance

项目摘要 毒性和耐药性限制了巨细胞病毒抗病毒治疗的疗效 巨细胞病毒(CMV)病在免疫抑制的宿主，如癌症和移植受者。 目前的治疗方法包括DNA聚合酶抑制剂更昔洛韦、磷甲酸钠和西多福韦。 终止酶抑制剂来特莫韦最近被批准用于预防，UL97 作为替代疗法，激酶抑制剂maribavir已经完成了3期试验。在临床上 实践中，CMV耐药性不能通过病毒的直接表型测试来诊断 而是依赖于检测到的病毒突变的准确相关性 以及相关的耐药表型。这项研究的目的是确定 为提高临床诊断率和提高CMV耐药性的遗传机制 新的抗病毒药物的开发。多药耐药基因突变和多态 CMV UL97激酶、UL54 DNA聚合酶和UL56/UL89/UL51终止酶基因 一直并将继续进行表型分析，具有诊断意义的新耐药基因座 在每个项目期间被识别。重组技术的研究进展 表型分析和全基因组深度测序为这项研究提供了便利。在 即将到来的项目期，新的重点领域包括突变的表征 在药物暴露于已知抗病毒靶点外的基因后选择，并分析 基线病毒株变异对药物敏感性的影响。具体目标是(1) 研究巨细胞病毒在体外或体外发生突变后的进化和表型 体内暴露于抗病毒化合物及其组合；(2)评估表型 病毒全基因组深度测序确定的基因变化的意义 是在已知的抗病毒靶基因之外，以及(3)确定基线的影响 用替代病毒特性研究病毒株的药敏表型 克隆和宿主细胞。

Project Summary Toxicity and drug resistance limit the efficacy of antiviral therapy for cytomegalovirus (CMV) disease in immunosuppressed hosts such as cancer and transplant recipients. Current therapy includes DNA polymerase inhibitors ganciclovir, foscarnet and cidofovir. The terminase inhibitor letermovir was recently approved for prophylaxis, and the UL97 kinase inhibitor maribavir has completed Phase 3 trial as alternative therapy. In clinical practice, CMV drug resistance cannot be diagnosed by direct phenotypic testing of viral isolates, and instead is dependent on an accurate correlation of detected viral mutations and associated resistance phenotypes. The objective of this research is to determine the genetic mechanisms of CMV drug resistance in order to improve clinical diagnosis and the development of new antivirals. Many resistance mutations and polymorphisms in the CMV UL97 kinase, UL54 DNA polymerase and UL56/UL89/UL51 terminase genes have been and continue to be phenotyped, with diagnostically important new resistance loci being identified during each project period. Technical advances in recombinant phenotyping and whole genome deep sequencing are facilitating this research. In the upcoming project period, new focus areas include the characterization of mutations selected after drug exposure in genes outside of known antiviral targets, and analysis of the effects of baseline viral strain variation on drug susceptibility. Specific aims are (1) study the evolution and phenotypes of CMV mutations that develop after in vitro or in vivo exposure to antiviral compounds and combinations; (2) evaluate the phenotypic significance of genetic changes identified by viral whole genome deep sequencing that are outside of known antiviral target genes, and (3) determine the impact of baseline viral strain on drug susceptibility phenotypes by characterization of alternative viral clones and host cells.