Mucosal health and microbiota during sea lice parasitism: effect of oral delivery of immunomodulants

海虱寄生期间的粘膜健康和微生物群：口服免疫调节剂的影响

• 批准号: MR/N026438/1
• 负责人: Daniel Merrifield
• 金额: $ 33.06万
• 依托单位: Plymouth University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=MR%2FN026438%2F1
• 关键词: Mucosal; health; microbiota; during; sea

The mucosal surfaces (skin, intestine and gills) of fish are constantly interacting with a wide range of pathogens and, in concert with the resident mucosal microbiota, are the first line of host defence. Several immune factors have been described in fish mucus and their presence and abundance can be affected by pathogen infection. As a consequence, the mucosa-associated microbiota can be affected and this may lead to dysbiosis, a microbial imbalance on or inside the body, which reduces the beneficial role of microbiota on the innate immune system and may lead to secondary infections by opportunistic microbes. Sea lice (Lepeophtheirus salmonis and Caligus spp.) infections are the most economically important causative agents of disease in marine-farmed salmonids worldwide. Caligus rogercresseyi is the main ectoparasite affecting the Chilean salmon industry with estimated costs of up to $120 million annually. This parasite damages external surfaces of the integument providing portal of entry for secondary infectious pathogens, and infected fish also become stressed which leads to immunosuppression with consequent increased susceptibility to the secondary infections. Other Caligid parasites (Caligus rogercresseyi and other Caligus spp.) have detrimental impacts on mariculture operations in both developing and developed parts of the world which causes economic losses of US$ 100's millions annually. The development of novel methods to prevent or reduce sea lice infection is therefore a high priority for the industry. An essential prerequisite for improved treatments strategies is a better understanding of relationship between host-microbiome-parasite at the epidermal interface. Therefore, the aim of this research programme is to evaluate the influence of sea lice parasitism on mucosal health, including aspects of the immune response and host microbiota. We will evaluate the effect of immunomodulants on susceptibility to sea lice infection, and on gut and mucus quality by determining epidermal mucus proteomic responses, microbiota changes and mucosal transcriptomic changes. We will correlate the responses of the host and the sea lice during the early stages of parasitism in order to develop new strategies (i.e. identify antigens for vaccines, targets for RNAi, probiotics, prebiotics, immunomodulants) for sea ice control.

鱼的粘膜表面（皮肤、肠和鳃）不断与各种病原体相互作用，与常驻粘膜微生物群一起，是宿主防御的第一道防线。几种免疫因子已经在鱼粘液中被描述，它们的存在和丰度可以受到病原体感染的影响。因此，粘膜相关的微生物群可能受到影响，这可能导致生态失调，身体上或身体内的微生物失衡，这降低了微生物群对先天免疫系统的有益作用，并可能导致机会微生物的继发感染。海虱（鲑虱（Lepeophtheirus salmonis）和Caligus spp.）感染是全世界海洋养殖鲑鱼中最经济上重要的疾病病原体。Caligus rogercresseyi是影响智利鲑鱼产业的主要体外寄生虫，估计每年的成本高达1.2亿美元。这种寄生虫破坏为继发性感染病原体提供入口的外皮的外表面，并且受感染的鱼也变得紧张，这导致免疫抑制，从而增加对继发性感染的易感性。其他卡里吉斯寄生虫（Caligus rogercresseyi和其他Caligus spp.）对世界上发展中国家和发达国家的海产养殖业产生不利影响，每年造成1亿美元的经济损失。因此，开发预防或减少海虱感染的新方法是该行业的高度优先事项。改进治疗策略的一个必要前提是更好地理解宿主-微生物组-寄生虫在表皮界面的关系。因此，本研究计划的目的是评估海虱寄生对粘膜健康的影响，包括免疫反应和宿主微生物群方面。我们将评估免疫调节剂对海虱感染易感性的影响，并通过确定表皮粘液蛋白质组学反应，微生物群变化和粘膜转录组学变化来评估肠道和粘液质量。我们将在寄生的早期阶段将宿主和海虱的反应相关联，以开发新的策略（即识别疫苗抗原，RNAi靶点，益生菌，益生元，免疫调节剂）用于海冰控制。