Smyrli Maria, Anka Ishrat Zahan, Koutsoni Olga, Dotsika Eleni, Kyriazis Ioannis D, Pavlidis Michail, Katharios Pantelis
University of Crete, Department of Biology, Voutes University Campus, Heraklion, 70013, Greece; Hellenic Centre for Marine Research, Institute of Marine Biology, Biotechnology and Aquaculture, Former American Base of Gournes, Heraklion, 71500, Greece.
University of Crete, Department of Biology, Voutes University Campus, Heraklion, 70013, Greece; Chattogram Veterinary and Animal Sciences University, Chittagong, Bangladesh.
Fish Shellfish Immunol. 2022 Apr;123:381-387. doi: 10.1016/j.fsi.2022.03.019. Epub 2022 Mar 19.
Aeromonas veronii bv. sobria is an emerging pathogen for the European seabass cultured in the Aegean Sea (Mediterranean) causing significant problems in the Greek and Turkish aquaculture industry since no licensed vaccine is currently available for the disease. A bivalent vaccine was developed based on two phenotypically distinct strains of the pathogen, PDB (motile, pigment-producing strain) and NS (non-motile, non-pigment-producing). The two strains comprising the bivalent vaccine were evaluated as monovalent products in zebrafish before the seabass trials. Challenges using the homologous or the heterologous strain showed that both vaccines were protective with RPS values ranging between 66 and 100% in zebrafish. The bivalent vaccine was then tested in European seabass following dip or intraperitoneal administration. Efficacy was evaluated separately against both strains comprising the bivalent vaccine. Dip vaccination applied to juvenile seabass of 2.5 g average weight provided protection following challenge tests 30 days post vaccination only in one of the two strains tested (strain PDB, RPS: 88%). This was also the case in the injection vaccination of adult seabass of 60 g average weight where the vaccine was effective only against the PDB strain (RPS: 63%). High antibody titers against both strains were found at 30 and 60 days after intraperitoneal vaccination in the adult seabass. The use of zebrafish as a model for vaccine development for aquaculture species is discussed.
维氏气单胞菌温和生物变种是爱琴海（地中海）养殖的欧洲鲈鱼的一种新出现的病原体，由于目前尚无针对该疾病的许可疫苗，给希腊和土耳其的水产养殖业带来了重大问题。基于该病原体的两种表型不同的菌株PDB（运动性、产色素菌株）和NS（非运动性、不产色素菌株）开发了一种二价疫苗。在鲈鱼试验之前，将构成二价疫苗的两种菌株作为单价产品在斑马鱼中进行了评估。使用同源或异源菌株进行攻毒试验表明，两种疫苗在斑马鱼中均具有保护作用，RPS值在66%至100%之间。然后，二价疫苗在欧洲鲈鱼中进行了浸浴或腹腔注射给药测试。分别针对构成二价疫苗的两种菌株评估了疫苗效力。对平均体重为2.5克的幼鱼进行浸浴接种，在接种后30天进行攻毒试验时，仅对测试的两种菌株之一（菌株PDB，RPS：88%）提供了保护。在平均体重为60克的成年鲈鱼进行注射接种时也是如此，疫苗仅对PDB菌株有效（RPS：63%）。在成年鲈鱼腹腔接种后30天和60天发现了针对两种菌株的高抗体滴度。本文讨论了将斑马鱼用作水产养殖物种疫苗开发模型的情况。
