Cell lines and primary cultures uses for vaccine development for Bacterial pathogens of fish: a systematic review

Abstract

Global fish aquaculture faces severe challenges due to outbreaks of pathogenic bacteria, which cause diseases resultingin high fish mortality rates and significantly impactproduction, sector economics, and environmental and social stability. One prominent approach to combat these diseases and reduce mortality involves vaccine development. Cell lines and primary cultures providea straightforwardand economicalmodel to evaluatevaccine efficacy. This study systematically reviewsthe use of cell lines and primary cultures in vaccinedevelopment for bacterial pathogens affecting fish. We conducted asystematic literature search across Web of Science, PubMed, and Scopus databases followingPRISMA guidelines. Out of an initial1,123 studies published up to August 2024 screened for eligibility, only 24 met the criteria for inclusion based on relevanceto vaccine development for bacterial fish pathogens. Our review identified16 cell lines and four primary cultures with potential applications for vaccine development in fish species such as rainbow trout, olive flounder, grass carp, Asian seabass (barramundi), Atlantic salmon, and tilapia. Keyapplications of cell lines and primary culturesin vaccine development involve immunostimulatory and immunomodulatory effects (9/24; 37.5%), cytotoxicity testing (8/24; 33.3%), and DNA vaccine fabrication via transfection (6/24; 25%). However, our findings reveal limited availability of cell lines in biobanks, which hampers result reproducibility. We conclude that,despite the high potential of cell lines and primary cultures for vaccine development, these models are established as routine tools in only a few fish species.