Investigating local determinants of outcome in human tuberculosis

结核病是一种感染，每年造成大约150万人死亡，并且对用于治疗结核病的抗生素的耐药性越来越强。了解结核病的一个核心挑战是，人体的免疫反应需要控制感染，但也会引起炎症，导致肺损伤和感染扩散。此外，在同一个体中，某些感染区域可以进展，而其他区域可以消退，这表明是局部因素决定了结果。结核病是一种人类独有的疾病，因此要充分了解这种复杂的相互作用，需要一个可以研究的人类实验室系统，以确定潜在的过程。我们已经开发了一种全新的方法，通过开发一种方法，我们感染人类细胞，然后将它们封装到微型球体中进行长期分析。这样做的好处是，我们可以比通常的实验室系统更长时间地监测感染，并且我们已经证明，人类细胞的行为和对抗生素的反应等关键特征与传统系统相比，与患者中观察到的更相似。在本工作方案中，我们将使用两种不同但互补的方法来确定是什么调节了结核病感染在个体病变中的结果。首先，我们将修改微球环境和组成，以确定哪些因素导致感染的最佳控制。我们将在球体周围添加炎症介质并测量感染的进展。接下来，我们将调节我们封装在微球中的免疫细胞的数量和激活。最后，我们将改变球体内的纤维。这些实验将告诉我们哪些条件有助于免疫系统最有效地控制感染，同时，我们将设计一个高灵敏度的摄像系统，使我们能够测量每个微球体内的感染情况，因为细菌经过基因改造，可以自发发光。我们将测量感染随时间的进展，然后研究感染得到控制的微球内的细胞与感染正在进展的微球内的细胞。我们将提取细胞并使用最新的单细胞分析技术测量它们的激活，以了解控制感染所需的特征。最后，我们将研究结核病患者的组织，再次比较进行性病变和控制性病变，以证实我们在患者疾病部位的微球中的观察结果。综上所述，我们的发现将告诉我们为什么有些结核病病变会进展，有些会消退，这对于指导疫苗接种和肺保护性治疗等新策略以控制全球流行至关重要。

Tuberculosis is an infection which kills approximately one and a half million people each year, and is becoming increasingly resistant to the antibiotics used to treat it. A central challenge in understanding tuberculosis is that the body's immune response is needed to control infection, but also causes the inflammation that leads to lung damage and spread of infection. In addition, in the same individual, some areas of infection can progress whilst other regress, indicating that it is local factors that determine outcome. Tuberculosis is exclusively a disease of humans, and therefore to fully understand this complex interaction requires a human laboratory system that can be studied to determine the underlying processes.We have developed an entirely new way of investigating infection in the laboratory by developing a method where we infect human cells and then encapsulate them into mini-spheres for long-term analysis. This has the benefit that we can monitor the infection for much longer than the usual laboratory systems, and we have shown that key features like the behaviour of human cells and the response to antibiotics is more similar to that observed in patients than traditional systems. In this programme of work, we will use two different but complementary approaches to determine what regulates the outcome of tuberculosis infection in individual lesions. First, we will modify the mini-sphere environment and composition to determine which factors lead to optimal control of infection. We will add inflammatory mediators around the spheres and measure the progress of infection. Next, we will modulate the number and activation of immune cells that we encapsulate in the mini-spheres. Finally, we will change the fibres within the spheres. Together, these experiments will tell us which conditions help the immune system control infection most effectively.In parallel, we will design a highly sensitive camera system, which allows us to measure infection within each mini-sphere, as the bacteria have been genetically modified to spontaneously produce light. We will measure the progress of infection over time, and then study the cells within mini-spheres where infection is being controlled versus those where the infection is progressing. We will extract the cells and measure their activation using the latest single cell profiling techniques, to understand which characteristics are needed to control infection. Finally, we will study tissue from patients with tuberculosis, again comparing progressive and controlling lesions, to confirm our observations in mini-spheres at the site of disease in patients.Taken together, our findings will tell us why some tuberculosis lesions progress and some regress, which is essential knowledge to inform new strategies such as vaccination and lung-protective treatments to control the global epidemic.