Escribano Rodríguez, María del PilarBalado Dacosta, MiguelEstévez Toranzo, María Alicia CarolinaLemos Ramos, Manuel LuisMagariños Ferro, Beatriz2025-03-182025-03-182024-10-05Escribano MP, Balado M, Santos B, Toranzo AE, Lemos ML, Magariños B. Outer membrane vesicles (OMVs) from Tenacibaculum maritimum as a potential vaccine against fish tenacibaculosis. Fish Shellfish Immunol. 2024 Nov;154:109943. doi: 10.1016/j.fsi.2024.109943. Epub 2024 Oct 5https://hdl.handle.net/10347/40296Outer membrane vesicles (OMVs) have been gained increasing attention in vaccinology due to their ability to induce strong protective humoral and cell-mediated immunity. The Gram-negative bacterium Tenacibaculum maritimum, the causative agent of marine tenacibaculosis, poses a significant challenge to the global aquaculture industry due to its difficult prophylaxis. In previous studies, we demonstrated that OMV production is a key virulence mechanism in T. maritimum. Building on this, the present study aimed to evaluate the efficacy of a natural, encapsulated multi-antigen vaccine made from adjuvant-free, crude T. maritimum OMVs (Tm-OMVs). A vaccination experiment using SP9.1-OMVs was conducted in juvenile turbot (Scophthalmus maximus L.), followed by a T. maritimum bath challenge. Immune responses in the turbot were assessed by measuring anti-Tm antibody levels and analyzing the expression of eight key immune-related genes (il-1β, il-8, il-22, pcna, c3, cd4-1, ifng2, cd8α). The results showed that immunization with SP9.1-OMVs provided significant protection against T. maritimum infection (RPS = 70 %). Vaccinated fish exhibited a dose-dependent increase in anti-Tm antibody titers in blood plasma, along with rapid induction of both innate (il-1β, il-8, il-22, c3) and adaptive (cd4-1, ifng2, cd8α) immune genes as early as 4 h post-bath challenge. These findings offer new insights into the early immune response of turbot following T. maritimum infection and could serve as a foundation for developing novel OMV-based vaccineseng© 2024 The Authors. Published by Elsevier Ltd.Attribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/TenacibaculumTenacibaculosisOuter membrane vesicles (OMV)Aquaculture vaccinesImmune response2414 Microbiología240112 Parasitología animaljournal article10.1016/j.fsi.2024.1099431050-4648open access