Eötvös Loránd Kutatási Hálózat-Eötvös Loránd Tudományegyetem (ELKH-ELTE) Research Group of Peptide Chemistry, Eötvös Loránd Research Network, Eötvös Loránd University, Budapest, Hungary.
Institute of Chemistry, Eötvös Loránd University, Budapest, Hungary.
Front Immunol. 2021 Nov 12;12:750496. doi: 10.3389/fimmu.2021.750496. eCollection 2021.
One of the main hallmarks of tuberculosis (TB) is the ability of the causative agent to transform into a stage of dormancy and the capability of long persistence in the host phagocytes. It is believed that approximately one-third of the population of the world is latently infected with (), and 5%-10% of these individuals can develop clinical manifestations of active TB even decades after the initial infection. In this latent, intracellular form, the is shielded by an extremely robust cell wall and becomes phenotypically resistant to most antituberculars. Therefore, there is a clear rationale to develop novel compounds or carrier-conjugated constructs of existing drugs that are effective against the intracellular form of the bacilli. In this paper, we describe an experimental road map to define optimal candidates against intracellular and potential compounds effective in the therapy of latent TB. To validate our approach, isoniazid, a first-line antitubercular drug was employed, which is active against extracellular in the submicromolar range, but ineffective against the intracellular form of the bacteria. Cationic peptide conjugates of isoniazid were synthesized and employed to study the host-directed drug delivery. To measure the intracellular killing activity of the compounds, -infected MonoMac-6 human monocytic cells were utilized. We have assessed the antitubercular activity, cytotoxicity, membrane interactions in combination with internalization efficacy, localization, and penetration ability on interface and tissue-mimicking 3D models. Based on these data, most active compounds were further evaluated in a murine model of TB. Intraperitoneal infectious route was employed to induce a course of slowly progressive and systemic disease. The well-being of the animals, monitored by the body weight, allows a prolonged experimental setup and provides a great opportunity to test the long-term activity of the drug candidates. Having shown the great potency of this simple and suitable experimental design for antimicrobial research, the proposed novel assay platform could be used in the future to develop further innovative and highly effective antituberculars.
结核分枝杆菌（TB）的主要特征之一是其病原体转变为休眠期的能力以及在宿主吞噬细胞中长期存在的能力。据信，世界上约有三分之一的人口潜伏感染了 ，其中 5%-10%的人即使在初次感染几十年后也可能出现活动性 TB 的临床表现。在这种潜伏的、细胞内的形式中， 被极其坚固的细胞壁所屏蔽，并对大多数抗结核药物表现出表型耐药。因此，开发针对杆菌细胞内形式的新型化合物或现有药物的载体偶联构建物具有明确的合理性。在本文中，我们描述了一条实验路线图，以确定针对细胞内 和潜在化合物在潜伏性结核病治疗中的有效性。为了验证我们的方法，我们使用了异烟肼，一种一线抗结核药物，它在亚微摩尔范围内对细胞外 有效，但对细菌的细胞内形式无效。合成了异烟肼的阳离子肽缀合物，并将其用于研究宿主导向的药物递送。为了测量化合物的细胞内杀菌活性，我们使用了感染 - 的 MonoMac-6 人单核细胞。我们评估了化合物的抗结核活性、细胞毒性、与内化功效、定位和穿透能力相结合的膜相互作用，以及在界面和组织模拟 3D 模型上的穿透能力。基于这些 数据，我们进一步评估了最有效的化合物在 TB 的小鼠模型中的活性。采用腹腔感染途径诱导缓慢进展和系统性疾病。通过体重监测动物的健康状况，可以延长实验时间，并为测试候选药物的长期活性提供机会。鉴于该实验设计在抗菌研究中的强大潜力，这种简单且适合的实验设计可用于未来开发更具创新性和高效的抗结核药物。
