Rapid assessment of phage for combating antimicrobial resistance in Enterobacter cloacae using a novel insect model

抗生素，可以用来治疗和预防细菌感染的药物，已经彻底改变了我们治疗传染病和预防手术感染的能力。不幸的是，细菌可以通过进化对抗生素产生抗药性。它们可以经历基因变化，使它们能够耐受或降解抗生素。我们认为，有必要考虑一整套解决耐药性的创新办法。一个重要的可能解决方案是增加我们使用“生物”溶液来治疗感染，例如被称为噬菌体的杀菌病毒。虽然噬菌体疗法有其局限性，但它们可以与抗生素结合使用，从而提高治疗效果，并有助于减缓耐药性的演变速度。进化实验需要时间，而且可能需要许多不同的宿主。虽然噬菌体有许多未开发的潜力，但目前通过在实验室哺乳动物身上进行耐药性进化实验来证明这些工具的有效性是困难和昂贵的。为此，我们专门开发了一种昆虫系统来研究阴沟肠杆菌对抗生素的耐药性演变。这一物种特别难以治疗，因为它对许多青霉素类抗生素具有天然耐药性。它是膀胱和肾脏感染以及重症监护相关感染的重要原因。我们的昆虫模型捕捉了脊椎动物感染的许多重要方面，但还具有易于操作、不受伦理监督和成本效益高的额外好处。有了这个模型，我们可以改变抗生素的消耗，抗性质粒的存在和许多重要的条件，这将使我们能够模拟大量个体宿主的不同现实世界场景。我们将使用实验进化来评估部署噬菌体以减缓耐药性进化的一系列方法。这将包括使用病毒特异性地杀死那些携带对抗生素产生耐药性的遗传元素的细菌。我们将研究如何最好地部署噬菌体与噬菌体的结合，以及如何最好地利用噬菌体来对抗不同形式的耐药性。我们还将研究可能影响噬菌体在耐药性管理中的价值的重要因素，例如肠道中细菌的多样性。通过昆虫实验，我们可以发现如果我们改变一系列控制措施，几周或几个月后会发生什么。如果我们在现实世界中做到这一点，将会更加困难，成本更高，而且可能需要数年时间。这样一个实验系统永远不会是完美的，但它会给我们一个很好的想法，将会发生什么，便宜和快速。虽然昆虫模型不能完全解决抗生素耐药性问题，但我们相信它们可以提供一个重要的新工具。有了它，我们就可以快速地在人口规模上观察各种可能的耐药性管理方案的有效性，并挑选出最好的方案，稍后在医院或动物健康方面进行试验。

Antibiotics, drugs that can be used to treat and prevent bacterial infection, have revolutionized our ability to treat infectious disease and prevent infection during surgery. Unfortunately bacteria can become resistant to antibiotics by evolving. They can undergo genetic changes that enable them to tolerate or degrade antibiotics. We believe that there is a need to consider a whole raft of innovative solutions to resistance. One important possible solution is to increase our use of "biological" solutions to treat infections, such as the bacteria-killing viruses known as bacteriophage. While bacteriophage remedies have their limitations, they can be combined with antibiotics in a way that can improve treatment efficacy and also help slow the rate of the evolution of resistance. Evolution experiments require time and potentially many different hosts. While phage has much unexploited potential, currently it is difficult and expensive demonstrate the effectiveness of these tools by doing evolution of resistance experiments with laboratory mammals. For this proposal, we have specifically developed an insect system to investigate the evolution of resistance to antibiotics in the bacterium Enterobacter cloacae. This species is particularly difficult to treat because of its naturally occurring resistance to many penicillin-based antibiotics. It is an important cause of bladder and kidney infections as well as infections associated with intensive care. Our insect model captures many of important aspects of infections in vertebrates but has the added benefits of being easy to manipulate, free of ethical oversight, and very cost effective. With this model we can vary antibiotic consumption, the presence of resistance plasmids and numerous important conditions that will allow us to mimic different real world scenarios with large numbers of individual hosts. We will use experimental evolution to assess a range of ways of deploying bacteriophages to slow the evolution of resistance. This will include the use of virus to specifically kill those bacteria carrying genetic elements that confer resistance to antibiotics. We will investigate how to best to deploy bacteriophage in combination with phage, and how best to use phage to combat different forms of resistance. We will also look at important factors that might affect the value of phage in resistance management, such as the diversity of the bacteria in the gut. With the insect experiments we can find out what happens in weeks or months, if we change a range of control measures. If we would do this in the real world, it would be harder, more expensive and potentially take years. Such an experimental system will never be perfect, but it will give us a good idea what will happen, cheaply and quickly.While the insect models cannot entirely solve the problem of antibiotic resistance, we believe that they could provide an important new tool. With it we can rapidly look at the effectiveness of a large range of possible resistance management options on a population scale, and pick out the best ones, which can later be tried out in hospitals or in animal health.