Towards therapy-induced lethal HIV mutagenesis

描述（由申请人提供）：HIV-1治疗的局限性，包括病毒耐药性和脱靶效应，为识别新药靶点和开发新的抗HIV-1药物提供了动力。之前的体外数据发现，两种临床批准的药物地西他滨和吉西他滨在单独使用时抗病毒活性最低的浓度下联合使用，可将HIV-1的感染性降低73%。感染性降低与突变频率的显著增加和HIV-1突变谱的转变相一致，这是通过将形成非典型碱基对的核苷类似物与某些核糖核苷酸还原酶抑制剂相结合来实现的。增加的突变负荷被认为是抑制从前病毒产生感染性子代病毒的主要抗病毒机制，并支持增加的突变频率通过致死性诱变降低感染性的模型。在本申请中，我们提出测试的假设，即易错病毒复制可能会导致“错误灾难”或灭绝，在体内由于有害突变的积累。设计用于驱动病毒错误灾难的策略已应用于HIV-1和许多RNA病毒，但在大多数情况下，它们尚未在体内评估其有效控制HIV复制的能力。在这里，我们建议使用一种新的人源化小鼠模型来研究1）地西他滨和吉西他滨在体内控制病毒复制的能力，和2）地西他滨/吉西他滨药物组合通过提高病毒突变载量来在体内控制HIV复制的能力。 公共卫生相关性：HIV-1耐药性和副作用可能会限制抗逆转录病毒活性的长期有效性，这就需要不断确定新的药物靶点和开发新的抗HIV-1药物。

DESCRIPTION (provided by applicant): The limitations of HIV-1 therapeutics, which include viral drug resistance and off-target effects, provide the impetus for the identification of novel drug targets and the development of new anti-HIV-1 drugs. Previous in vitro data found that the combination of two clinically approved drugs, decitabine and gemcitabine, reduced HIV-1 infectivity by 73% at concentrations that had minimal antiviral activity when used individually. Decreased infectivity coincided with a significant increase in mutant frequency and a shift in the HIV-1 mutant spectra by combining a nucleoside analog that forms non-canonical base pairs with certain ribonucleotide reductase inhibitors. Increased mutational load is implicated as the primary antiviral mechanism for inhibiting the generation of infectious progeny virus from provirus, and support a model in which increased mutation frequency decreases infectivity through lethal mutagenesis. In this application, we propose to test the hypothesis that error-prone viral replication may induce "error catastrophe" or extinction in vivo due to an accumulation of deleterious mutations. Strategies designed to drive viruses to error catastrophe have been applied to HIV-1 and a number of RNA viruses however for the most part they have not been evaluated in vivo for their ability to effectively control HIV replication. Here, we propose to use a novel humanized mouse model to investigate 1) the ability of decitabine and gemcitabine to control viral replication in vivo, and 2) the ability of the decitabine/gemcitabine drug combination to control HIV replication in vivo by elevating the viral mutational load. PUBLIC HEALTH RELEVANCE: HIV-1 drug resistance and side effects can limit the long-term effectiveness of antiretroviral activity, requiring the continual need for the identification of novel drug targets and the development of new anti-HIV-1 drugs.