Closing the Gaps on Buruli Ulcer Diagnosis, Treatment, and Prevention

缩小布鲁里溃疡诊断、治疗和预防方面的差距

• 批准号: 9030108
• 负责人: ERIC L NUERMBERGER
• 金额: $ 94.57万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-12-09 至 2020-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9030108
• 关键词: Aftercare; Animal Model; Animals; Anti-HIV Agents; Anti-Retroviral Agents; Antibiotic Therapy; Antibiotics; Antibodies; Antibody Affinity; Architecture; Bacterial Toxins; Bacteriophages; Binding; Biological Assay; Biological Markers; Blood; Buruli Ulcer; Cavia; Cell membrane; Cells; Clinical Drug Development; Clinical Trials; Combined Antibiotics; Complex; Computer Simulation; Data; Detection; Development; Diagnosis; Diagnostic; Diagnostic tests; Disease; Dose; Drug Interactions; Early Diagnosis; Excision; Exudate; Future; Goals; High Density Lipoproteins; Human; Individual; Infection; Injection of therapeutic agent; Knowledge; Lesion; Link; Lipid Bilayers; Lipids; Membrane; Methods; Modeling; Molecular Target; Mus; Mycobacterium ulcerans; Operative Surgical Procedures; Oral; Partner in relationship; Pathogenesis; Patients; Pharmaceutical Preparations; Prevention; Production; Regimen; Research; Rifampin; Role; Serum; Skin graft; Staging; Streptomycin; System; Therapeutic; Therapeutic Effect; Tissues; Toxic effect; Toxin; Treatment Protocols; Treatment outcome; Tropical Disease; Tuberculosis; Ulcer; Vesicle; Virulence; Virulence Factors; Work; Wound Healing; Yeasts; base; chemotherapy; cytotoxicity; drug development; experience; human tissue; improved; in vivo; innovation; liquid chromatography mass spectrometry; mouse model; mycolactone; neglect; novel; novel drug combination; novel therapeutics; point of care; point-of-care diagnostics; pre-clinical; prevent; public health relevance; research clinical testing; tool; tuberculosis drugs

 DESCRIPTION (provided by applicant): Buruli ulcer (BU) is a disfiguring and debilitating, yet neglected and emerging, tropical disease caused by Mycobacterium ulcerans via its unique lipid toxin, mycolactone. Before 2004, the only treatment was wide surgical excision and skin grafting. Studies in mouse footpad models first indicated the efficacy of rifampin plus streptomycin (RIF+STR). Following confirmatory clinical trials, RIF+STR for 8 wks. was endorsed by the WHO as a first-line treatment for BU. The greatest gap in BU control is now the lack of simple, rapid, point-of- care diagnostics to confirm the diagnosis at an early stage of disease, when RIF+STR is most effective. To overcome this critical bottleneck, we will develop novel, fieldable, highly sensitive methods for mycolactone detection in blood and tissue. While many have tried and failed to generate anti-mycolactone antibodies, our approach using powerful novel methods of phage and yeast display to select reproducible high-affinity antibodies from extremely large and diverse naïve and patient-derived pools have already proven successful in select- ing specific antibodies to mycolactone alone and mycolactone bound to a known in vivo target, WASP. Previous efforts to detect anti-mycolactone antibodies in patients or immunized animals were also based on the flawed premise that the toxin exists in a free form in vivo. Based on our prior experience with other amphiphilic biomarkers and computational modeling of mycolactone's interaction with lipid bilayers, we strongly believe that, outside host cells, mycolactone will always exist in complexes with host carriers such as high-density lip- oprotein (HDL) or in association with cell membranes or membrane-derived vesicles. Therefore, our approach is to combine our knowledge of putative carriers and a discovery approach proven successful for other am- phiphilic biomarkers to identify the most prevalent and relevant host mycolactone complexes and inhabited membrane architectures in vivo, select antibodies to those species and employ those antibodies in our innova- tive, highly sensitive and fieldable detection system. The 8-wk RIF+STR regimen requires injections with a relatively toxic agent (STR) and use of RIF, which causes many drug-drug interactions (e.g., with anti-HIV drugs). We will explore the development of shorter, simpler, entirely oral regimens based on recent advances in tuberculosis drug development and promising preliminary data in BU mouse models. We will leverage our experience in pre-clinical drug development for both diseases as well as our established relationships with the sponsors of new drugs in clinical trials. This will e carried out with tools developed with support from R01-AI082612, to comprehensively evaluate novel drug combinations for BU and prioritize them for clinical evaluation. Finally, because persistence of mycolac- tone in tissues during and after treatment may retard bacterial clearance and wound healing, we will exploit knowledge from our diagnostic discovery work pursue innovative antibody- and non-antibody-based "anti- virulence" strategies, seeking to neutralize mycolactone's toxic effects for adjunctive therapeutic benefit.

 描述（由申请人提供）：布鲁里溃疡 (BU) 是一种导致毁容、使人衰弱但又被忽视的新兴热带疾病，由溃疡分枝杆菌通过其独特的脂质毒素分枝杆菌内酯引起，2004 年之前，唯一的治疗方法是广泛的手术切除和植皮。小鼠足垫模型研究首先表明了利福平加链霉素 (RIF+STR) 的功效，随后进行了验证性临床试验，RIF+STR。 8 周被世界卫生组织认可作为 BU 的一线治疗方法。目前 BU 控制方面的最大差距是缺乏简单、快速的护理点诊断来在疾病的早期阶段确认诊断。当 RIF+STR 最有效时，为了高度克服这一关键瓶颈，我们将开发用于血液和组织中分枝菌内酯检测的新颖、可现场使用的灵敏方法。的方法噬菌体和酵母展示从极其庞大和多样化的天然和患者来源的池中选择可重复的高亲和力抗体，已经证明可以成功地选择单独的分枝菌内酯的特异性抗体和与已知的体内靶点 WASP 结合的分枝菌内酯的特异性抗体。 -患者或免疫动物中的分枝菌内酯抗体也是基于这样一个有缺陷的前提：毒素在体内以游离形式存在，并且基于我们之前对其他两亲性生物标志物的经验。通过计算分枝菌内酯与脂质双层相互作用的模型，我们坚信，在宿主细胞之外，分枝菌内酯将始终以与宿主载体（例如高密度脂蛋白（HDL））的复合物形式存在，或者与细胞膜或膜衍生囊泡相关。因此，我们的方法是将我们对推定载体的知识与已证明对其他两亲性生物标志物成功的发现方法结合起来，以确定最普遍和相关的宿主分枝菌内酯复合物和体内存在的膜结构，选择这些物种的抗体，并将这些抗体应用于我们创新的、高灵敏度和可现场检测系统中。8 周 RIF+STR 方案需要注射相对毒性剂 (STR) 并使用 RIF，这引起许多药物间相互作用（例如，与抗 HIV 药物）。我们将根据结核病药物开发的最新进展和 BU 小鼠的有希望的初步数据，探索开发更短、更简单、完全口服的治疗方案。我们将利用我们在这两种疾病的临床前药物开发方面的经验以及我们与新药申办者在临床试验中建立的关系，这将利用在 R01-AI082612 支持下开发的工具来进行。最后，由于治疗期间和治疗后组织中的霉菌内酯的持续存在可能会阻碍细菌清除和伤口愈合，因此我们将利用我们的诊断发现工作中的知识来追求创新的抗体和药物。非基于抗体的“抗毒力”策略，寻求中和分枝菌内酯的毒性作用以获得辅助治疗效果。