p38 MAP kinase inhibitors as therapeutics targeting ebolavirus entry

描述(申请人提供)：丝状病毒，埃博拉和马尔堡病毒(EBOV和MARV)，是新出现的包膜负义RNA病毒和NIAID A类优先病原体。目前，还没有获得批准的抗丝状病毒疗法。巨噬细胞和树突状细胞(DC)是体内感染EBOV特别重要的细胞类型。这些是支持高效病毒复制的早期感染目标。有证据表明，这些细胞类型的感染会导致异常反应，从而导致EBOV疾病。例如，感染的巨噬细胞产生促炎细胞因子，可能促进血管渗漏，感染的DC可能调节失调，损害对感染的免疫反应。因此，预防这些细胞类型的感染或改变它们对感染的反应的治疗方法可能被证明是有益的。初步研究表明，以前被描述为p38 MAPK(P38 MAPK)抑制剂的小分子化合物可在原代人巨噬细胞和DC中削弱扎伊尔EBOV病毒样颗粒(VLP)的进入并抑制扎伊尔EBOV的复制。这些数据提示，p38蛋白可能在EBOV进入巨噬细胞和DC过程中发挥重要作用。他们还提出，p38的MAP激酶可能是有用的抗EBOV药物。除了抑制进入和复制的能力外，p38抑制剂作为抗EBOV药物也很有趣，因为它们已经被开发为抗炎药物。因此，它们也可能在体内抑制病毒诱导的炎症。此外，一些p38抑制剂已经进入了人体临床试验阶段。因此，有许多现成的p38MAPK抑制剂；并且有大量关于这些化合物的毒性、药代动力学和药效学的文献，这些文献有助于从体外研究过渡到主要的动物疗效研究。本项目将在体外和小鼠体内进一步评估p38 MAP激酶抑制剂作为抗丝病毒药物的作用。它将首先确定商业上可获得的p38MAPK抑制剂在细胞培养和小鼠中的抗病毒效果，并确定是否通过抑制p38MAPK来抑制EBOV进入和复制。其次，它将确定p38 MAP激酶抑制剂在EBOV诱导的细胞培养和体内细胞因子产生中的影响。最后，它将验证p38 MAP激酶是巨噬细胞吞噬介导的EBOV进入巨噬细胞和树突状细胞所必需的假说。在其结论中，这些药物作为抗病毒药物的潜力 将定义丝状病毒进入抑制物和病毒炎症抑制物；将揭示EBOV在巨噬细胞和DC中进入途径的新细节。

DESCRIPTION (provided by applicant): The filoviruses, Ebola and Marburg viruses (EBOV and MARV), are emerging, enveloped, negative-sense RNA viruses and NIAID category A priority pathogens. Currently, there are no approved anti-filovirus therapeutics. Macrophages and dendritic cells (DCs) are cell types particularly important for EBOV infection in vivo. These are early targets of infection that support productive virus replication. Evidence suggests that infection of these cell types leads to aberrant responses that contribute to EBOV disease. For example, infected macrophages produce proinflammatory cytokines that may promote vascular leakage, and infected DCs may be dysregulated, impairing immune responses to infection. Therefore, therapeutics that prevent infection of these cell types or that modify their responses to infection may prove beneficial. Preliminary studies have demonstrated that small molecule compounds previously characterized as p38 MAP kinase (p38 MAPK) inhibitors impair, in primary human macrophages and DCs, entry of Zaire EBOV virus-like particles (VLPs) and inhibit Zaire EBOV replication. These data suggest that p38 MAP kinases may play an important role in EBOV entry into macrophages and DCs. They also suggest that p38 MAP kinases may be useful as anti-EBOV drugs. In addition to their ability to inhibit entry and replication, p38 inhibitors are intriguing as anti- EBOV agents because they have been developed as anti-inflammatory drugs. Therefore, they may also suppress virus-induced inflammation in vivo. In addition, some p38 inhibitors have progressed as far as human clinical trials. Therefore, there are a number of readily available p38 MAPK inhibitors; and there is a substantial literature on the toxicity, pharmacokinetics and pharmcodynamics of these compounds that could facilitate the transition from in vitro studies to proof of principle animal efficacy studies. This project wil further evaluate p38 MAP kinase inhibitors as anti-filoviral agents in vitro and in mice. It will frst define the antiviral efficacy of commercially-available p38 MAP kinase inhibitors in cell culture and in mice and determine whether the inhibition of EBOV entry and replication occurs through inhibition of p38 MAPKs. Second, it will determine the impact of p38 MAP kinase inhibitors on EBOV-induced cytokine production in cell culture and in vivo. Finally, it will test the hypothesis that p38 MAP kinases are required for macropinocytosis-mediated entry of EBOV into macrophages and dendritic cells. At its conclusion, the potential for these drugs to serve as anti- filovirus entry inhibitors and suppressors of viral inflammation will be defined; and new details o the EBOV entry pathway in macrophages and DCs will be revealed.