Oehlers Stefan H, Cronan Mark R, Scott Ninecia R, Thomas Monica I, Okuda Kazuhide S, Walton Eric M, Beerman Rebecca W, Crosier Philip S, Tobin David M
Department of Molecular Genetics and Microbiology, Center for Microbial Pathogenesis, Duke University Medical Center, Durham, North Carolina 27710, USA.
Department of Molecular Medicine and Pathology, The University of Auckland, Auckland 1023, New Zealand.
Nature. 2015 Jan 29;517(7536):612-5. doi: 10.1038/nature13967. Epub 2014 Nov 24.
Pathogenic mycobacteria induce the formation of complex cellular aggregates called granulomas that are the hallmark of tuberculosis. Here we examine the development and consequences of vascularization of the tuberculous granuloma in the zebrafish-Mycobacterium marinum infection model, which is characterized by organized granulomas with necrotic cores that bear striking resemblance to those of human tuberculosis. Using intravital microscopy in the transparent larval zebrafish, we show that granuloma formation is intimately associated with angiogenesis. The initiation of angiogenesis in turn coincides with the generation of local hypoxia and transcriptional induction of the canonical pro-angiogenic molecule Vegfaa. Pharmacological inhibition of the Vegf pathway suppresses granuloma-associated angiogenesis, reduces infection burden and limits dissemination. Moreover, anti-angiogenic therapies synergize with the first-line anti-tubercular antibiotic rifampicin, as well as with the antibiotic metronidazole, which targets hypoxic bacterial populations. Our data indicate that mycobacteria induce granuloma-associated angiogenesis, which promotes mycobacterial growth and increases spread of infection to new tissue sites. We propose the use of anti-angiogenic agents, now being used in cancer regimens, as a host-targeting tuberculosis therapy, particularly in extensively drug-resistant disease for which current antibiotic regimens are largely ineffective.
致病性分枝杆菌会诱导形成称为肉芽肿的复杂细胞聚集体,而肉芽肿是结核病的标志。在这里,我们在斑马鱼-海分枝杆菌感染模型中研究结核性肉芽肿血管生成的发展及其后果,该模型的特征是具有坏死核心的有组织的肉芽肿,与人类结核病的肉芽肿极为相似。利用透明幼体斑马鱼的体内显微镜技术,我们发现肉芽肿的形成与血管生成密切相关。血管生成的启动又与局部缺氧的产生以及经典促血管生成分子Vegfaa的转录诱导同时发生。对Vegf通路的药理学抑制可抑制与肉芽肿相关的血管生成,减轻感染负担并限制传播。此外,抗血管生成疗法与一线抗结核抗生素利福平以及靶向缺氧细菌群体的抗生素甲硝唑具有协同作用。我们的数据表明,分枝杆菌会诱导与肉芽肿相关的血管生成,从而促进分枝杆菌的生长并增加感染向新组织部位的传播。我们建议将目前用于癌症治疗方案中的抗血管生成药物用作针对宿主的结核病治疗方法,特别是对于目前抗生素治疗方案大多无效的广泛耐药疾病。