Host-pathogen interactions important in the movement of Campylobacter jejuni from the broiler chicken gut to edible tissues (CampAttack)

安全鸡肉的可持续生产是一项国际优先事项，据估计，在未来20年内，鸡肉产量必须翻两番，才能满足日益增长的全球需求。关键问题是，能否在不增加受污染鸡肉对公众健康威胁的情况下做到这一点，并保护鸡肉的健康和福利。国际上消费的大部分鸡肉都是在大规模集约化(肉鸡)系统中生产的，英国大多数禽类(&gt；75%)在零售时都是弯曲杆菌阳性，主要是空肠弯曲菌，这对公共健康构成了巨大的威胁。弯曲杆菌是英国细菌性腹泻的最常见原因，尽管有数百万英镑的研究资金，但据估计，受污染的鸡肉在2016年导致英国500000例人类弯曲杆菌病病例，约10万人死亡，其中大部分是老年人。感染的特征是剧烈的腹痛和急性(有时是血性)腹泻，每年给英国经济造成的损失超过10亿英镑。此外，弯曲杆菌不仅是鸡的主要人类病原体，而且还危害肉鸡的健康、福利和生产性能。弯曲杆菌污染鸡肉的形式有两种。首先，屠宰过程中由于肠道内容物溢出而造成的屠体表面污染，可能会导致厨房的交叉污染。其次，肌肉和肝脏组织中的污染可能比目前认为的更重要，它通过促进烹饪过程中细菌的生存而增加了健康风险。直到最近，人们还认为弯曲杆菌只在鸡的下肠道(盲肠)定居。然而，从肠道传播到可食用组织与某些弯曲杆菌菌株在鸡的上肠道定植的能力有关，在那里，肠道衬里(粘膜)更容易受到破坏。由于弯曲杆菌在肉鸡中包含一个不同的种群，不同的菌株对肠道完整性的影响不同，它们传播到肝脏和肌肉等可食用组织的能力也不同，如果要控制鸡体内的弯曲杆菌并减少对公共卫生的威胁，更好地了解不同类型的宿主和病原体的相互作用是很重要的。特别是，必须确定关键的宿主免疫反应和在这些相互作用中最重要的细菌基因--以及在整个肠道和肠道外传播的定植过程中。这项多学科研究计划将加强对弯曲菌对禽类肠道健康、宿主先天免疫反应和传播至可食用组织的影响的了解，从而对公共健康构成威胁。定量信息和模型将用于向业界提供有关肉鸡弯曲杆菌感染生物学的直接建议，为缓解鸡肉中弯曲杆菌污染的持续挑战的干预提供前所未有的基础。这些干预措施可能包括新的疫苗和/或基因上更具抵抗力的鸡。

Sustainable production of safe chicken is an international priority and it is estimated that in the next 20 years chicken production will have to quadruple to satisfy growing global demand. The key question is whether this can be done in a way that does not increase the public health threat of contaminated chicken meat and preserves chicken health and welfare. Most chicken meat consumed internationally is produced in large-scale intensive (broiler) systems and most birds in the UK (>75%) are Campylobacter-positive at retail, mainly with C. jejuni, posing a huge public health threat. Campylobacter is the most common cause of bacterial diarrhoea in the UK and despite millions of pounds of research funding it is estimated that contaminated chicken caused >500000 human campylobacteriosis cases in the UK in 2016 with around 100 deaths, mainly in elderly people. Infection is characterised by severe abdominal pain and acute (sometimes bloody) diarrhoea and costs the UK economy over £1 billion per year. In addition, Campylobacter are not only major chicken-associated human pathogens, they also compromise the health, welfare and performance of broilers. Campylobacter contamination of chicken takes two forms. First, surface contamination of carcasses, as a result of spillage of gut contents during slaughter, can lead to cross-contamination in the kitchen. Second, and perhaps of greater importance than currently thought, is contamination within muscle and liver tissues, which increases the health risk by facilitating bacterial survival during cooking. Until recently it was believed that Campylobacter only colonised the lower gut of the chicken (the caecum). However, spread from the gut to edible tissues is associated with the ability of certain Campylobacter strains to colonise the upper intestine of the chicken, where the gut lining (mucosa) is more easily damaged. As Campylobacter comprise a diverse population in broilers, with different strains varying in their effects on gut integrity and their ability to spread to edible tissues like liver and muscle, it is important to better understand the host-pathogen interactions of different types if the bacteria are to be controlled in chickens and the public health threat reduced. In particular, it is essential to identify the key host immune responses and the bacterial genes most important in these interactions - and in colonisation of the whole gut and extra-intestinal spread. This information, which is currently not available, is essential for the development of immunity-based and other control measures.This multidisciplinary research programme will enhance understanding of the influence of Campylobacter strain on bird gut health, host innate immune responses and spread to edible tissues and thus the public health threat. The quantitative information and modelling will be used to give direct advice to industry about Campylobacter infection biology in broiler chickens, providing an unprecedented basis for interventions to mitigate the on-going challenge of Campylobacter contamination in chicken meat. These interventions potentially include new vaccines and/or genetically more resistant chickens.