Hoplite Laboratory, Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada.
Department of Veterinary Sciences, Universite de Montreal, Montreal, QC, Canada.
Front Immunol. 2019 Feb 4;10:120. doi: 10.3389/fimmu.2019.00120. eCollection 2019.
With respect to salmonid aquaculture, one of the most important bacterial pathogens due to high mortality and antibiotic usage is the causative agent of typical furunculosis, spp. (). In Atlantic salmon, , the host response during infections with is well-documented, with furunculosis outbreaks resulting in significant mortality in commercial settings. However, less is known about the host-pathogen interactions in the emerging aquaculture species, Arctic charr . Furthermore, there is no data on the efficacy or response of this species after vaccination with commonly administered vaccines against furunculosis. To this end, we examined the immunological response of during infection with , with or without administration of vaccines (Forte Micro®, Forte Micro® + Renogen®, Elanco Animal Health). Artic charr (vaccinated or unvaccinated) were i.p.-injected with a virulent strain of (10 CFUs/mL) and tissues were collected pre-infection/post-vaccination, 8, and 29 days post-infection. Unvaccinated Arctic charr were susceptible to with 72% mortalities observed after 31 days. However, there was 72-82% protection in fish vaccinated with either the single or dual-vaccine, respectively. Protection in vaccinated fish was concordant with significantly higher serum IgM concentrations, and following RNA sequencing and transcriptome assembly, differential expression analysis revealed several patterns and pathways associated with the improved survival of vaccinated fish. Most striking was the dramatically higher basal expression of complement/coagulation factors, acute phase-proteins, and iron hemostasis proteins in pre-challenged, vaccinated fish. Remarkably, following infection, this response was abrogated and instead the transcriptome was characterized by a lack of immune-stimulation compared to that of unvaccinated fish. Furthermore, where pathways of actin assembly and FcγR-mediated phagocytosis were significantly differentially regulated in unvaccinated fish, vaccinated fish showed either the opposite regulation (ForteMicro®), or no impact at all (ForteMicro®Renogen®). The present data indicates that vaccine-induced protection against relies on the pre-activation and immediate control of humoral immune parameters that is coincident with reduced activation of apoptotic (e.g., NF-κB) and actin-associated pathways.
就鲑鱼养殖业而言，由于高死亡率和抗生素的使用，最主要的细菌性病原体之一是典型疖病的病原体， spp. (). 在大西洋鲑鱼中， 感染期间的宿主反应已有详细记录，疖病爆发导致商业养殖中大量鱼类死亡。然而，对于新兴养殖品种北极红点鲑中的宿主-病原体相互作用知之甚少。此外，对于用通常用于疖病疫苗接种的疫苗接种后该物种的功效或反应尚无数据。为此，我们检查了 感染期间 的免疫反应，有无疫苗（Forte Micro®，Forte Micro®+ Renogen®，Elanco Animal Health）。用 10 CFU/mL 的强毒株对北极红点鲑（接种或未接种）进行腹腔注射，并在感染前/疫苗接种后、8 天和 29 天采集组织。未接种疫苗的北极红点鲑易受 感染，31 天后观察到 72%的死亡率。然而，分别用单一或双重疫苗接种的鱼类中有 72-82%的保护作用。接种疫苗的鱼类的保护作用与血清 IgM 浓度显著升高一致，并且在进行 RNA 测序和转录组组装后，差异表达分析显示了几种与接种疫苗鱼类生存改善相关的模式和途径。最引人注目的是，在预先挑战、接种疫苗的鱼类中，补体/凝血因子、急性期蛋白和铁止血蛋白的基础表达显著升高。值得注意的是，在 感染后，与未接种疫苗的鱼类相比，该反应被阻断，转录组的特征是缺乏免疫刺激。此外，在未接种疫苗的鱼类中，肌动蛋白组装和 FcγR 介导的吞噬作用途径的调节显著不同，而接种疫苗的鱼类表现出相反的调节（ForteMicro®）或根本没有影响（ForteMicro®Renogen®）。本数据表明，疫苗接种对 的保护作用依赖于对体液免疫参数的预先激活和即时控制，这与凋亡（如 NF-κB）和肌动蛋白相关途径的激活减少有关。
