Isolation and characterization of Clostridium perfringens lytic phages for veterinary applications in the poultry industry

产氧性产气荚膜梭菌（Cp）引起的坏死性肠炎是动物健康的负担，特别是在家禽业。由于Cp可通过食物链传播给人类，因此该病原体也是食品安全问题。在欧洲国家禁止使用抗菌生长促进剂之后，肉鸡群的健康问题几乎立即出现，由Cp引起的急性临床和亚临床坏死性肠炎的增加最为显著。加拿大关于抗菌生长促进剂使用的立法将于2018年底实施，加拿大家禽行业正面临缺乏合适和有效的替代品来预防肉鸡群健康问题。据估计，每年因坏死性肠炎爆发造成的全球经济损失总额超过25亿美元，迄今为止，该行业没有任何有效的补救办法。通过与SyntBioLabo公司合作的这个项目，我们寻求开发能够在噬菌体治疗应用中杀死Cp的裂解噬菌体（即细菌病毒）鸡尾酒。虽然以前已经分离出Cp噬菌体，并且已经证明噬菌体治疗可以预防鸡的坏死性肠炎，但数据很少，可用的Cp噬菌体也很少。此外，这些噬菌体必须针对目前在家禽养殖场中流行的细菌菌株。**目标：我们的第一个目标将是从目前在魁北克省8个家禽养殖场流行的鸡粪便中分离出Cp菌株。我们的第二个目标将包括筛选粪便样本，以检测针对目标1中发现的80-90%最流行的Cp菌株的毒力噬菌体。为了达到我们的目标，我们将使用成熟的微生物和分子方法来表征Cp菌株，以及分离的噬菌体。在这个项目结束时，我们的目标是收集15-20个可以组合成鸡尾酒的裂解噬菌体。这个项目将加强我们对Cp噬菌体的生物学、多样性和治疗潜力的基本认识。由于人类和动物都可以感染Cp，因此本项目的成功对未来人类噬菌体治疗Cp具有重要的里程碑意义。＊＊＊＊

Necrotic enteritis caused by the toxigenic bacterium Clostridium perfringens (Cp) is a burden on animal health, especially in the poultry industry. This pathogen is also a concern for food safety as Cp can be transmitted to human through the food chain. The ban of antimicrobial growth promoter use in European countries was almost immediately followed by health problems in broiler flocks, with the most remarkable increase in acute clinical and subclinical necrotic enteritis caused by Cp. Canadian legislation on antimicrobial growth promoter use will be enforced by the end of 2018 and the Canadian poultry industry is facing the lack of suitable and efficient alternatives to prevent health problem in broiler flocks. The total global economic loss due to outbreaks of necrotic enteritis is estimated to be over $2.5 billions annually and, to date, the industry does not have any efficient remedy for the problem. With this project in collaboration with SyntBioLabo Inc., we seek to develop cocktails of lytic phages (i.e. bacterial viruses) capable of killing Cp in phage therapy applications. Although Cp phages have been isolated before and phage therapy to prevent necrotic enteritis in chickens has been demonstrated, there is little data and few Cp phages available. Moreover, these phages must target the bacterial strains currently circulating in poultry farms.**Objectives: Our first objective will consist in isolating from chicken feces Cp strains currently in circulation in 8 poultry farms of the province of Quebec. Our second objective will consist in screening fecal samples to detect virulent phages against 80-90% of the most prevalent Cp strains identified in objective 1. To reach our goals, we will use well-established microbiological and molecular methods to characterize Cp strains, as well as the isolated phages. By the end of this project, we aim to gather 15-20 lytic phages that could be combined into a cocktail. This project will reinforce our fundamental understanding of the biology, diversity, and therapeutic potential of Cp phages. Because Cp can infect both humans and animals, success of our project could represent an important milestone for future phage therapy of Cp in humans. ****