RT Journal Article
T1 Nervous necrosis virus (NNV) vaccination of carrier Senegalese sole (Solea senegalensis)
A1 Souto Pereira, Sandra
A1 Olveira Hermida, José Gabriel
A1 López Vázquez, Carmen
A1 Pereira Dopazo, Carlos
A1 Labella, Alejandro M.
A1 Bandín Matos, Isabel
K1 Senegalese sole
K1 Nervous necrosis virus
K1 NNV carrier
K1 Immune response
K1 Vaccination
AB Viral encephalopathy and retinopathy (VER), caused by nervous necrosis virus (NNV), is one of the most threatening diseases affecting marine farmed fish, especially in early developmental stages. In addition, subclinical infections are commonly detected in both farmed and wild fish. In recent years numerous efforts have been made to achieve effective vaccines for the protection of different fish species against NNV infection. Vaccination experiments are always conducted on pathogen-free animals, but subclinically infected individuals may respond differently to immunization. In this study, we have observed a different response between experimentally-induced-NNV carrier Senegalese sole and NNV-free animals when immunized with a BEI-inactivated vaccine, whereas mock-vaccinated carrier fish behaved like the NNV-free group. Analysis of the immune response after vaccination showed specific antibody production as well as up-regulation of the genes coding for the proinflammatory cytokines IL-6 and IL-8, the antiviral protein HERC4 and the cytotoxic T lymphocyte (CTL) and T helper markers CD8 and CD4 in vaccinated NNV-free and mock-vaccinated carrier individuals. However, no significant antibody production was detected and only cd4 up-regulation was recorded in the vaccinated carrier fish. After challenge, viral replication was similar in the vaccinated groups up to 15 days post-challenge (dpc), although thereafter the viral load in the vaccinated carrier fish reached values similar to the control fish, whereas in the vaccinated NNV-free sole remained 1.5–2 log lower. At 2 dpc 10% mortality was recorded in the vaccinated carrier group that did not correlate with a higher viral titre, but with an overexpression of inflammation-related genes. These results suggest that an acute inflammatory reaction could have been the cause of the fish death. Excepting the values recorded in this episode, poor modulation of the immune response was observed at the early days post-challenge. However, at 30 dpc the IgM levels in the vaccinated carrier fish were significantly higher than those of the NNV-free sole. Longer post-vaccination studies would be necessary to clarify if this antibody increase may be relevant for fish protection
PB Elsevier
SN 0044-8486
YR 2024
FD 2024
LK http://hdl.handle.net/10347/32952
UL http://hdl.handle.net/10347/32952
LA eng
NO Aquaculture, Volume 579, 2024, 740211
NO This research was funded by Ministerio de Ciencia, Innovación y Universidades (MICIU), the Agencia Estatal de Investigación (AEI) and FEDER, grant number RTI2018-094687-B-C21. Dr. Sandra Souto was funded with a postdoctoral grant from Consellería de Cultura, Educación y Universidad, Xunta de Galicia (postdoctoral grant ED481D-2022/024). The authors are grateful to Stolt Sea Farm for kindly providing the fish, J. Franqueira for technical assistance and Native English School of Languages for the English revision
DS Minerva
RD 27 abr 2026