Dual Targeting of Mtb Resistance Mechanisms

摘要 结核分枝杆菌（Mtb）是人类结核病（TB）的病原体，目前导致近 1.7每年有100万人死亡结核病控制受到耐药结核分枝杆菌菌株不断出现的威胁。 现在已经观察到对所有结核病药物的临床耐药性，这突出表明迫切需要的不仅仅是新的结核病药物， 药物，而是直接针对和禁用耐药机制的全新策略。两 在结核病治疗中预防抗生素耐药性出现的最有希望的策略是 靶向药物耐受性、非复制性细菌群体和宿主导向疗法（HDT）。我们确定了一个 一系列药物样ATP类似物，其对复制型和非复制型Mtb的体外活性相当 利福平是针对非复制型结核病的一线药物之一。因为这些抑制剂 最初开发用于抑制人转化生长因子受体（TGFβR）， 与结核病免疫有关，我们还试图测试TGFβR的抑制是否介导宿主导向活性 针对结核病。我们发现TGFβR的基因缺失和化学抑制显著降低了细菌 感染的动物。我们发现，缺乏TGFβR的T细胞在一个特定的细胞周期中相互作用的能力增加。 与Mtb感染的巨噬细胞同源的方式，并在肺部感染部位产生IFNγ。这些 初步研究为长期存在的问题提出了一个新的答案，为什么T细胞对结核分枝杆菌的反应是 在感染部位的不足，并强调了TGFβ信号转导是一个新的HDT靶点的可能性。因此，在本发明中， 我们发现了具有两种独立活性的化合物，它们既可以杀死结核病，又可能阻止结核病的出现 抗药性的证据。使用遗传学和ATP类似物作为化学工具，我们将确定细胞Mtb目标 负责直接杀死Mtb，从而确定药物耐受性的新靶点。在东道主方面，我们 将决定TGFβR信号转导在结核分枝杆菌感染中的作用。最后，我们将测试这种双重宿主-病原体靶向 通过测试我们的化合物在体内的功效，

ABSTRACT Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB) in humans, currently leads to nearly 1.7 million deaths a year. TB control is threatened by the continued emergence of drug-resistant Mtb strains. Clinical resistance has now been observed against all TB drugs, underscoring the urgent need not just for new drugs, but for entirely new strategies that directly target and disable drug resistance mechanisms. Two of the most promising strategies to prevent the emergence of antibiotic resistance in the treatment of TB are the targeting of drug tolerant, non-replicating bacterial populations and host-directed therapy (HDT). We identified a series of drug-like ATP analogs with in vitro activity against replicating and non-replicating Mtb that is comparable to that of rifampicin, one of the first-line drugs targeting non-replicating Mtb. Because these inhibitors were originally developed for the inhibition of the human transforming growth factor receptor (TGFβR), a pathway implicated in immunity to TB, we also sought to test whether inhibition of TGFβR mediates host-directed activity against Mtb. We found that genetic deletion and chemical inhibition of TGFβR significantly reduced the bacterial load in infected animals. We showed that T-cells lacking TGFβR had an increased capacity to interact in a cognate manner with Mtb-infected macrophages and produce IFNγ at the pulmonary site of infection. These preliminary studies suggest a new answer to the longstanding question why the T cell response to Mtb is inadequate at the site of infection and highlights the possibility that TGFβ signaling is a new HDT target. Thus, we identified compounds that have two independent activities that both kill Mtb and likely impede the emergence of drug resistance. Using genetics and the ATP analogs as chemical tools, we will identify the cellular Mtb targets responsible for directly killing Mtb, thus identifying new targets that underlie drug tolerance. On the host side, we will determine the role of TGFβR signaling in Mtb infection. Lastly, we will test this dual host-pathogen targeting strategy by testing the efficacy of our compounds in vivo.