BIOCHEMICAL PHARMACOLOGY OF ANTIVIRAL DRUG THERAPY

拟议研究的总体目标仍然是阐明 药物作用的生物化学决定因素以及 用于治疗病毒感染的协同药物组合。 的 5 ′-氨基胸苷与病毒和宿主的非正常相互作用 细胞胸苷激酶提出了几种新的方法， 疱疹病毒感染治疗的改进。 第一、 阐明反馈抑制的作用和可能的拮抗作用， 这种调节抗疱疹化合物活化的作用， 提出了 5 '-AdThd和其他5'-氨基衍生物与人的免疫反应的能力 破坏胸苷激酶活性的调节，从而， 增强单纯疱疹病毒中抗病毒核苷的活化 (HSV)并测定水痘带状疱疹病毒（VZV）感染的细胞。 其次，5 '-AdThd抑制磷酸化，因此， 三氟胸苷（CF 3dUrd）在未感染细胞中的毒性。 此外，本发明还提供了一种方法， CF 3dUrd是人巨细胞病毒（HCMV）的一种极好的抑制剂， 体外 由于没有有效的治疗这种感染的体内是可用的， CF 3dUrd和5 ′-AdThd组合选择性抑制 将评估HCMV复制。 CF 3dUrd代谢模式 单独和与5 ′-AdThd组合，在HCMV感染的细胞中的作用将是 阐明。 第三，根据基因数据，有人提出， 胸苷激酶是干扰素抗病毒的重要决定因素 活动 在某些细胞中，5 '-AdThd可以调节细胞中胸苷激酶的活性。 双向的方式 在低浓度下，5 '-AdThd可刺激酶 通过拮抗三磷酸胸苷介导的反馈活性 抑制作用 然而，在较高浓度下， 胸苷激酶的活性位点占优势，活性受到抑制。 这一新的性质表明了一种生物化学方法来评估 胸苷激酶对干扰素活性影响 使用5 '-AdThd， 将评价干扰素的抗疱疹和抗增殖作用 在对照条件下，刺激和抑制胸苷水平 激酶活性 在胸苷激酶阳性和 将进行阴性细胞。 这种方法可以提供一个 调节干扰素活性的生化手段。

The overall objectives of the proposed research continue to be elucidation of the biochemical determinants of drug action and the development of synergistic drug combinations for the treatment of viral infections. The unsual interactions between 5'-aminothymidine (5'-AdThd) and viral and host cell thymidine kinases suggest several new approaches which may lead to improvements in the therapy of herpes virus infections. Firstly, elucidation of the role of feedback inhibition and possible antagonism of this effect in regulating the activation of antiherpes compounds is proposed. The ability of 5'-AdThd and other 5'-amino derivatives to disrupt the regulation of thymidine kinase activities and, thereby, to enhance the activation of antiviral nucleosides in herpes simplex virus (HSV) and varicella zoster virus (VZV) infected cells will be determined. Secondly, 5'-AdThd inhibits the phosphorylation and, therefore, the toxicity of trifluorothymidine (CF3dUrd) in unifected cells. In addition, CF3dUrd is an excellent inhibitor of human cytomegalovirus (HCMV) in vitro. Since no effective therapy for this infection in vivo is available, the ability of CF3dUrd and 5'-AdThd, in combination, to selectively inhibit HCMV replication will be assessed. The pattern of CF3dUrd metabolism alone, and in combination with 5'-AdThd, in HCMV infected cells will be elucidated. Thirdly, based on genetic data, it has been suggested that thymidine kinase is an important determinant of interferon's antiviral activity. In some cells 5'-AdThd can modulate thymidine kinase activity in a biphasic manner. At low concentrations 5'-AdThd can stimulate enzyme activity by antagonizing thymidine triphosphate mediated feedback inhibition. At higher concentrations, however, interactions with the active site of thymidine kinase predominate and activity is inhibited. This novel property suggests a biochemical approach to evaluate the influence of thymidine kinase on interferon activity. Using 5'-AdThd, the antiherpes and antiproliferative actions of interferon will be evaluated under conditions of control, stimulated and inhibited levels of thymidine kinase activity. Experiments in both thymidine kinase positive and negative cells will be conducted. This approach could provide a biochemical means of modulating interferon activity.