Potent inhibition of HIV-1 latency reversal by PF 03758309

摘要 潜伏的、具有复制能力的HIV-1病毒在静息的CD4+T细胞中的持久性是一个主要的 治愈HIV-1感染的障碍。到目前为止，通过休克和杀死方法根除这种病毒库的努力 在细胞和/或动物模型中都没有导致完全的、长期的病毒抑制。因此，我们需要 考虑可能导致HIV-1感染的绝育或功能性治疗的替代方法。这座街区 而锁定方法寻求沉默潜伏的前病毒的转录活性，这样当抗逆转录病毒 治疗(ART)被取消，病毒反弹被显著推迟，或者更好的是，阻止了病毒反弹。几项研究 研究小组已经确定了针对HIV-1转录的不同因素的小分子抑制剂 机械，导致一种阻塞和锁定的表型。然而，仅阻断一条转录途径可能不会 足以压制所有威胁，因此，这一战略的成功实施很可能将 需要多种抑制剂的组合。在这方面，迫切需要识别具有不同特征的新分子 行动机制。我们实验室最近发现，p21激活的激酶(PAK)抑制剂Pf-1。 03758309是一种非常有效的HIV-1潜伏期重新激活的抑制剂(IC50值在PM到低NM范围内) 巨大的选择性指数(&gt；3000)。(发现PF-03758309是艾滋病毒-1潜伏期逆转的抑制剂 描述于：Vargas B，Giacobbi NS，Sanyal A，Venkatachari NJ，han F，Gupta P，Sluis-Cremer N。 抗菌剂化学试剂。阻断HIV-1潜伏期逆转的信号通路抑制剂。2019年 1月29日；63(2)。PII：E01744-18。)从长远来看，我们预计PF-03758309单独或与 其他药物，可以用来促进艾滋病毒感染者的“封锁和锁定”消毒治疗。然而， 我们不知道这种抑制剂(S)通过什么机制阻止潜伏的HIV-1感染在体内重新激活 CD4+T细胞。事实上，我们实验室的初步研究表明，它对HIV-1潜伏期逆转的抑制作用 并不是由于对PAK的抑制。因此，这项R21提案的主要目标是阐明 PF-03758309沉默HIV-1病毒的机制(S)。

SUMMARY The persistence of latent, replication-competent HIV-1 proviruses in resting CD4+ T cells represents a major barrier to curing HIV-1 infection. To date, efforts to eradicate this viral reservoir via the shock and kill approach have not led to complete, long term viral suppression in either cell and/or animal models. Thus, we need to consider alternate approaches that could lead to a sterilizing or functional cure for HIV-1 infection. The block and lock approach seeks to silence the transcriptional activity of latent proviruses, such that when antiretroviral therapy (ART) is removed viral rebound is significantly delayed or, better yet, prevented. Several research groups have identified small molecule inhibitors that target different factors of the HIV-1 transcription machinery, leading to a block and lock phenotype. However, blocking only one transcription pathway may not be sufficient to silence all proviruses, and thus it is likely that successful implementation of this strategy will require a combination of inhibitors. In this regard, there is a critical need to identify new molecules with different mechanisms of action. Our laboratory recently discovered that the p21-activated kinase (PAK) inhibitor PF- 03758309 is an exceptionally potent inhibitor of HIV-1 latency reactivation (IC50 in the pM to low nM range) with a huge selectivity index (> 3,000). (The discovery of PF-03758309 as an inhibitor of HIV-1 latency reversal is described in: Vargas B, Giacobbi NS, Sanyal A, Venkatachari NJ, Han F, Gupta P, Sluis-Cremer N. Antimicrob Agents Chemother. Inhibitors of Signaling Pathways That Block Reversal of HIV-1 Latency. 2019 Jan 29;63(2). pii: e01744-18.) In the long term, we anticipate that PF-03758309 alone, or in combination with other drugs, could be used to facilitate a “block and lock” sterilizing cure in HIV-infected individuals. However, we do not know the mechanism(s) by which this inhibitor abrogates the reactivation of latent HIV-1 infection in CD4+ T cells. Indeed, preliminary studies in our laboratory revealed that its inhibition of HIV-1 latency reversal is not due to inhibition of the PAKs. Accordingly, the primary goal of this R21 proposal is to elucidate the mechanism(s) by which PF-03758309 silences HIV-1 proviruses.