Genetic Pathways of Human Cytomegalovirus Drug Resistance

人类巨细胞病毒耐药性的遗传途径

• 批准号: 8859479
• 负责人: Sunwen Chou
• 金额: $ 15.75万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2020-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8859479
• 关键词: Alternative Therapies; Antiviral Agents; Antiviral Therapy; Binding; Binding Sites; Cells; Chromosome Mapping; Cidofovir; Clinical; Clinical Trials; Complex; Cytomegalovirus; DNA; DNA Polymerase Inhibitor; DNA biosynthesis; DNA-Directed DNA Polymerase; Data; Development; Diagnosis; Disease; Drug Exposure; Drug Formulations; Drug resistance; Drug resistance pathway; Equilibrium; Evolution; Exonuclease; Exposure to; Figs - dietary; Foscarnet; Ganciclovir; Genes; Genetic; Genetic Polymorphism; Genotype; Growth; Hypersensitivity; Immunocompromised Host; In Vitro; Laboratories; Licensing; Malignant Neoplasms; Mediating; Mission; Molecular; Morphologic artifacts; Mutagenesis; Mutation; Oral; Pathway interactions; Pattern; Pharmaceutical Preparations; Phase; Phenotype; Phosphotransferases; Polymerase; Polymerase Gene; Positioning Attribute; Prodrugs; Recombinants; Reporter Genes; Research; Resistance; Resistance profile; Structure; System; Technology; Therapeutic; Toxic effect; Transplant Recipients; Valganciclovir; Viral; base; cost; design; drug candidate; fitness; genetic resistance; improved; in vivo; inhibitor/antagonist; kinase inhibitor; maribavir; mutant; next generation sequencing; nucleoside analog; protein expression; public health relevance; resistance mechanism; resistance mutation; terminase; viral DNA

 DESCRIPTION (provided by applicant): Toxicity and drug resistance limit the efficacy of antiviral therapy for cytomegalovirus (CMV) disease in immunosuppressed hosts such as cancer and transplant recipients. The basic objective of this research is to characterize the viral mutations and associated mechanisms of resistance to anti-CMV drugs in clinical use, in order to improve the genotypic diagnosis of CMV drug resistance and the selection and development of alternate therapies. For currently licensed drugs (ganciclovir, foscarnet and cidofovir), many resistance mutations and polymorphisms in the CMV UL97 kinase and UL54 DNA polymerase genes have been and continue to be identified and phenotyped, sometimes as mixed subpopulations. Clinical trials of new anti-CMV drugs have recently accelerated, including the UL97 kinase inhibitor maribavir, the terminase inhibitor letermovir, and additional DNA polymerase inhibitors brincidofovir and cyclopropavir. Defining the genetics of resistance and cross-resistance among these compounds is an essential aspect of these new antiviral treatment options. Technical advances in genotyping and recombinant phenotyping are facilitating this research, including efficient mutagenesis of cloned baseline laboratory strains expressing reporter genes for viral quantitation, tagged protein expression systems and next-generation sequencing technology. Specific aims are (1) define the evolution and phenotypes of CMV mutations that develop after in vitro or in vivo exposure to antiviral compounds; (2) elucidate mechanisms of DNA chain extension by which the same exonuclease mutations can confer resistance to some polymerase inhibitors but hypersensitivity to others, and (3) characterize the genetic pathways of resistance to terminase inhibitors with emphasis on mutations in a region of the UL56 gene that confer high-level letermovir resistance.

 描述（由申请人提供）：毒性和耐药性限制了免疫抑制宿主（例如癌症和移植受者）中巨细胞病毒（CMV）疾病的抗病毒治疗的功效。本研究的基本目的是表征病毒 临床使用抗CMV药物耐药突变及相关机制，以提高CMV耐药基因型诊断和替代疗法的选择和开发。对于目前获得许可的药物（更昔洛韦、膦甲酸和西多福韦），CMV UL97 激酶和 UL54 DNA 聚合酶基因中的许多耐药突变和多态性已经并继续被鉴定和表型，有时作为混合亚群。新型抗巨细胞病毒药物的临床试验最近加速进行，包括 UL97 激酶抑制剂马里巴韦、终止酶抑制剂莱特莫韦以及其他 DNA 聚合酶抑制剂布西多福韦和环丙韦。定义这些化合物之间的耐药性和交叉耐药性的遗传学是这些新的抗病毒治疗方案的一个重要方面。基因分型和重组表型的技术进步正在促进这项研究，包括对表达用于病毒定量的报告基因的克隆基线实验室菌株进行有效诱变、标记蛋白表达系统和下一代测序技术。具体目标是 (1) 定义体外或体内暴露于抗病毒化合物后发生的 CMV 突变的进化和表型； (2) 阐明 DNA 链延伸机制，通过这种机制，相同的核酸外切酶突变可以赋予对某些聚合酶抑制剂耐药性，但对其他聚合酶抑制剂过敏，并且 (3) 描述对终止酶抑制剂耐药性的遗传途径，重点关注 UL56 基因区域中赋予高水平莱特莫韦耐药性的突变。