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González-Fernández C, García-Álvarez MA, Cuesta A. Identification and functional characterization of fish IL-17 receptors suggest important roles in the response to nodavirus infection. MARINE LIFE SCIENCE & TECHNOLOGY 2024; 6:252-265. [PMID: 38827125 PMCID: PMC11136934 DOI: 10.1007/s42995-024-00225-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 03/18/2024] [Indexed: 06/04/2024]
Abstract
Th17 is a lymphocyte T helper (Th) subpopulation relevant in the control and regulation of the immune response characterized by the production of interleukin (IL)-17. This crucial cytokine family acts through their binding to the IL-17 receptors (IL-17R), having up to six members. Although the biology of fish Th17 is well-recognized, the molecular and functional characterization of IL-17 and IL-17R has been limited. Thus, our aim was to identify and characterize the IL-17R repertory and regulation in the two main Mediterranean cultured fish species, the gilthead seabream (Sparus aurata) and the European sea bass (Dicentrarchus labrax). Our in silico results showed the clear identification of six members in each fish species, from IL-17RA to IL-17RE-like, with well-conserved gene structure and protein domains with their human orthologues. All of them showed wide and constitutive transcription in naïve tissues but with highest levels in mucosal tissues, namely skin, gill or intestine. In leucocytes, T mitogens showed the strongest up-regulation in most of the il17 receptors though il17ra resulted in inhibition by most stimulants. Interestingly, in vivo nodavirus infection resulted in alterations on the transcription of il17 receptors. While nodavirus infection led to some increments in the il17ra, il17rb, il17rc and il17rd transcripts in the susceptible European sea bass, many down-regulations were observed in the resistant gilthead seabream. Our data identify the presence and conservation of six coding IL-17R in gilthead seabream and European sea bass as well as their differential regulation in vitro and upon nodavirus infection. Supplementary Information The online version contains supplementary material available at 10.1007/s42995-024-00225-1.
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Affiliation(s)
- Carmen González-Fernández
- Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, 30100 Murcia, Spain
- Laboratoire d’écotoxicologie, Centre de Lyon-Villeurbanne, INRAE, UR RiverLy, 69625 Villeurbanne, France
| | - Miguel A. García-Álvarez
- Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, 30100 Murcia, Spain
| | - Alberto Cuesta
- Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, 30100 Murcia, Spain
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García-Álvarez MA, Chaves-Pozo E, Cuesta A. Cytotoxic activity and gene expression during in vitro adaptive cell-mediated cytotoxicity of head-kidney cells from betanodavirus-infected European sea bass. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2024; 152:105124. [PMID: 38145864 DOI: 10.1016/j.dci.2023.105124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 12/19/2023] [Accepted: 12/19/2023] [Indexed: 12/27/2023]
Abstract
Cell-mediated cytotoxicity (CMC) is essential in eradicating virus-infected cells, involving CD8+ T lymphocytes (CTLs) and natural killer (NK) cells, through the activation of different pathways. This immune response is well-studied in mammals but scarcely in teleost fish. Our aim was to investigate the adaptive CMC using head-kidney (HK) cells from European sea bass infected at different times with nodavirus (NNV), as effector cells, and the European sea bass brain cell line (DLB-1) infected with different NNV genotypes, as target cells. Results showed low and unaltered innate cytotoxic activity through the infection time. However, adaptive CMC against RGNNV and SJNNV/RGNNV-infected target cells increased from 7 to 30 days post-infection, peaking at 15 days, demonstrating the specificity of the cytotoxic activity and suggesting the involvement of CTLs. At transcriptomic level, we observed up-regulation of genes related to T cell activation, perforin/granzyme and Fas/FasL effector pathways as well as apoptotic cell death. Further studies are necessary to understand the adaptive role of European sea bass CTLs in the elimination of NNV-infected cells.
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Affiliation(s)
- Miguel A García-Álvarez
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, 30100, Murcia, Spain
| | - Elena Chaves-Pozo
- Physiology and Welfare of Marine Species Group (PHYSIS), Centro Oceanográfico de Murcia (COMU-IEO), CSIC, Carretera de la Azohía s/n, Puerto de Mazarrón, 30860, Murcia, Spain
| | - Alberto Cuesta
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, 30100, Murcia, Spain.
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Cervera L, Chaves-Pozo E, Cuesta A. Synthetic Antimicrobial Peptides Fail to Induce Leucocyte Innate Immune Functions but Elicit Opposing Transcriptomic Profiles in European Sea Bass and Gilthead Seabream. Mar Drugs 2024; 22:86. [PMID: 38393057 PMCID: PMC10889969 DOI: 10.3390/md22020086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 02/08/2024] [Accepted: 02/12/2024] [Indexed: 02/25/2024] Open
Abstract
Antimicrobial peptides (AMPs) are promising molecules in diverse fields, including aquaculture. AMPs possess lytic effects on a wide range of pathogens, resulting in a potential replacement for traditional antimicrobials in aquaculture. In addition, they also have modulatory effects on host immune responses. Thus, the objective of this work was to evaluate the immunomodulatory capability of three known synthetic AMPs derived from European sea bass, NK-lysin (Nkl), hepcidin (Hamp), and dicentracin (Dic), in head-kidney cell suspensions from European sea bass and gilthead seabream. The tested peptides were neither cytotoxic for European sea bass nor gilthead seabream cells and failed to modulate the respiratory burst and phagocytosis activities. However, they modified the pattern of transcription of immune-related genes differently in both species. Peptides were able to promote the expression of marker genes for anti-inflammatory (il10), antiviral (mx, irf3), cell-mediated cytotoxicity (nccrp1, gzmb), and antibody responses (ighm) in European sea bass, with the Nkl peptide being the most effective. Contrary to this, the effects of those peptides on gilthead seabream mainly resulted in the suppression of immune responses. To conclude, European sea bass-derived peptides can be postulated as potential tools for immunostimulation in European sea bass fish farms, but more efforts are required for their universal use in other species.
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Affiliation(s)
- Laura Cervera
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, 30100 Murcia, Spain; (L.C.); (A.C.)
- Centro Oceanográfico de Murcia (COMU-IEO), CSIC, Carretera de la Azohía s/n, Puerto de Mazarrón, 30860 Murcia, Spain
| | - Elena Chaves-Pozo
- Centro Oceanográfico de Murcia (COMU-IEO), CSIC, Carretera de la Azohía s/n, Puerto de Mazarrón, 30860 Murcia, Spain
| | - Alberto Cuesta
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, 30100 Murcia, Spain; (L.C.); (A.C.)
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Toubanaki DK, Efstathiou A, Tzortzatos OP, Valsamidis MA, Papaharisis L, Bakopoulos V, Karagouni E. Nervous Necrosis Virus Modulation of European Sea Bass ( Dicentrarchus labrax, L.) Immune Genes and Transcriptome towards Establishment of Virus Carrier State. Int J Mol Sci 2023; 24:16613. [PMID: 38068937 PMCID: PMC10706053 DOI: 10.3390/ijms242316613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 11/16/2023] [Accepted: 11/20/2023] [Indexed: 12/18/2023] Open
Abstract
Viral infections of teleost fish have great environmental and economic implications in aquaculture. Nervous necrosis virus (NNV) is a pathogen affecting more than 120 different species, causing high mortality and morbidity. Herein, we studied the course of NNV experimental infection of D. labrax, focusing on survivors which indicated viral carrier state. To determine the carrier state of D. labrax head kidney, we performed a gene expression analysis of selected immune-related genes and we profiled its transcriptome 14 days post infection (dpi). All tested genes showed clear differentiations in expression levels while most of them were up-regulated 14 dpi suggesting that their role is not limited in early antiviral responses, but they are also implicated in disease persistence. To gain a better understanding of the fish that survived the acute infection but still maintained a high viral load, we studied the differential expression of 124 up-regulated and 48 down-regulated genes in D. labrax head kidney, at 14 dpi. Concluding, the NNV virus persistent profile was assessed in D. labrax, where immune-related gene modification was intense (14 dpi) and the head kidney transcriptome profile at this time point offered a glimpse into host attempts to control the infection in asymptomatic carriers.
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Affiliation(s)
- Dimitra K. Toubanaki
- Immunology of Infection Group, Department of Microbiology, Hellenic Pasteur Institute, 11521 Athens, Greece; (D.K.T.); (A.E.); (O.-P.T.)
| | - Antonia Efstathiou
- Immunology of Infection Group, Department of Microbiology, Hellenic Pasteur Institute, 11521 Athens, Greece; (D.K.T.); (A.E.); (O.-P.T.)
| | - Odysseas-Panagiotis Tzortzatos
- Immunology of Infection Group, Department of Microbiology, Hellenic Pasteur Institute, 11521 Athens, Greece; (D.K.T.); (A.E.); (O.-P.T.)
| | - Michail-Aggelos Valsamidis
- Department of Marine Sciences, School of the Environment, University of the Aegean, University Hill, Lesvos, 81100 Mytilene, Greece; (M.-A.V.); (V.B.)
| | | | - Vasileios Bakopoulos
- Department of Marine Sciences, School of the Environment, University of the Aegean, University Hill, Lesvos, 81100 Mytilene, Greece; (M.-A.V.); (V.B.)
| | - Evdokia Karagouni
- Immunology of Infection Group, Department of Microbiology, Hellenic Pasteur Institute, 11521 Athens, Greece; (D.K.T.); (A.E.); (O.-P.T.)
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Ortega-del Campo S, Díaz-Martínez L, Moreno P, García-Rosado E, Alonso MC, Béjar J, Grande-Pérez A. The genetic variability and evolution of red-spotted grouper nervous necrosis virus quasispecies can be associated with its virulence. Front Microbiol 2023; 14:1182695. [PMID: 37396376 PMCID: PMC10308047 DOI: 10.3389/fmicb.2023.1182695] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 05/23/2023] [Indexed: 07/04/2023] Open
Abstract
Nervous necrosis virus, NNV, is a neurotropic virus that causes viral nervous necrosis disease in a wide range of fish species, including European sea bass (Dicentrarchus labrax). NNV has a bisegmented (+) ssRNA genome consisting of RNA1, which encodes the RNA polymerase, and RNA2, encoding the capsid protein. The most prevalent NNV species in sea bass is red-spotted grouper nervous necrosis virus (RGNNV), causing high mortality in larvae and juveniles. Reverse genetics studies have associated amino acid 270 of the RGNNV capsid protein with RGNNV virulence in sea bass. NNV infection generates quasispecies and reassortants able to adapt to various selective pressures, such as host immune response or switching between host species. To better understand the variability of RGNNV populations and their association with RGNNV virulence, sea bass specimens were infected with two RGNNV recombinant viruses, a wild-type, rDl956, highly virulent to sea bass, and a single-mutant virus, Mut270Dl965, less virulent to this host. Both viral genome segments were quantified in brain by RT-qPCR, and genetic variability of whole-genome quasispecies was studied by Next Generation Sequencing (NGS). Copies of RNA1 and RNA2 in brains of fish infected with the low virulent virus were 1,000-fold lower than those in brains of fish infected with the virulent virus. In addition, differences between the two experimental groups in the Ts/Tv ratio, recombination frequency and genetic heterogeneity of the mutant spectra in the RNA2 segment were found. These results show that the entire quasispecies of a bisegmented RNA virus changes as a consequence of a single point mutation in the consensus sequence of one of its segments. Sea bream (Sparus aurata) is an asymptomatic carrier for RGNNV, thus rDl965 is considered a low-virulence isolate in this species. To assess whether the quasispecies characteristics of rDl965 were conserved in another host showing different susceptibility, juvenile sea bream were infected with rDl965 and analyzed as above described. Interestingly, both viral load and genetic variability of rDl965 in seabream were similar to those of Mut270Dl965 in sea bass. This result suggests that the genetic variability and evolution of RGNNV mutant spectra may be associated with its virulence.
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Affiliation(s)
- Sergio Ortega-del Campo
- Departamento de Biología Celular, Genética y Fisiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain
| | - Luis Díaz-Martínez
- Centro de Supercomputación y Bioinnovación (SCBI), Universidad de Málaga, Málaga, Spain
| | - Patricia Moreno
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain
- Instituto de Biotecnología y Desarrollo Azul, IBYDA, Universidad de Málaga, Málaga, Spain
| | - Esther García-Rosado
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain
- Instituto de Biotecnología y Desarrollo Azul, IBYDA, Universidad de Málaga, Málaga, Spain
| | - M. Carmen Alonso
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain
- Instituto de Biotecnología y Desarrollo Azul, IBYDA, Universidad de Málaga, Málaga, Spain
| | - Julia Béjar
- Departamento de Biología Celular, Genética y Fisiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain
- Instituto de Biotecnología y Desarrollo Azul, IBYDA, Universidad de Málaga, Málaga, Spain
| | - Ana Grande-Pérez
- Departamento de Biología Celular, Genética y Fisiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain
- Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”, Universidad de Málaga- Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), Málaga, Spain
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Leiva-Rebollo R, Gémez-Mata J, Castro D, Borrego JJ, Labella AM. Immune response of DNA vaccinated-gilthead seabream ( Sparus aurata) against LCDV-Sa infection: relevance of the inflammatory process. Front Immunol 2023; 14:1209926. [PMID: 37346045 PMCID: PMC10279854 DOI: 10.3389/fimmu.2023.1209926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 05/22/2023] [Indexed: 06/23/2023] Open
Abstract
Lymphocystis disease is one of the main viral pathologies affecting cultured gilthead seabream (Sparus aurata) in the Mediterranean region. Recently, we have developed a DNA vaccine based on the major capsid protein (MCP) of the Lymphocystis disease virus 3 (LCDV-Sa). The immune response triggered by either LCDV-Sa infection or vaccination have been previously studied and seem to be highly related to the modulation of the inflammatory and the IFN response. However, a comprehensive evaluation of immune-related gene expression in vaccinated fish after viral infection to identify immunogenes involved in vaccine-induced protection have not been carried out to date. The present study aimed to fulfill this objective by analyzing samples of head-kidney, spleen, intestine, and caudal fin from fish using an OpenArray® platform containing targets related to the immune response of gilthead seabream. The results obtained showed an increase of deregulated genes in the hematopoietic organs between vaccinated and non-vaccinated fish. However, in the intestine and fin, the results showed the opposite trend. The global effect of fish vaccination was a significant decrease (p<0.05) of viral replication in groups of fish previously vaccinated, and the expression of the following immune genes related to viral recognition (tlr9), humoral and cellular response (rag1 and cd48), inflammation (csf1r, elam, il1β, and il6), antiviral response (isg15, mx1, mx2, mx3), cell-mediated cytotoxicity (nccrp1), and apoptosis (prf1). The exclusive modulation of the immune response provoked by the vaccination seems to control the progression of the infection in the experimentally challenged gilthead seabream.
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Affiliation(s)
| | | | | | | | - Alejandro M. Labella
- Department of Microbiology, Faculty of Sciences, University of Malaga, Malaga, Spain
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García-Álvarez MÁ, González-Fernández C, Esteban MÁ, Cuesta A. Molecular characterization of the cytotoxic and regulatory T cell coreceptor (CRTAM), and its ligand CADM1, in the European seabass and gilthead seabream. FISH & SHELLFISH IMMUNOLOGY 2023; 134:108569. [PMID: 36720375 DOI: 10.1016/j.fsi.2023.108569] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 12/20/2022] [Accepted: 01/26/2023] [Indexed: 06/18/2023]
Abstract
T cell activation is a multifaceted process that depends on the activation of the T cell receptor (TCR). However, other coreceptors are also strictly necessary to provide co-signals and modulate the immune response. However, to date, most of these coreceptors are unknown in fish or their information is very limited. Therefore, in this work, we have identified the cytotoxic and regulatory T cell molecule, CRTAM, and its ligand, the cell adhesion molecule 1, CADM1, in European seabass (Dicentrarchus labrax) and gilthead seabream (Sparus aurata); and evaluated their transcriptional levels. Both putative proteins showed the canonical architecture observed in mammals, where CRTAM exhibited two immunoglobulin domains and CADM1, both the a and b forms, exhibited three of these domains. In addition, phylogeny and synteny analyses showed their conservation throughout vertebrate evolution. We found constitutive expression of all three genes, with crtam and cadm1a being predominant in immune tissues such as spleen, thymus and head-kidney (HK), while cadm1b expression was more limited to the brain. In vitro, only the T cell mitogen phytohemagglutinin (PHA) up-regulated the transcription of crtam and cadm1a in HK leucocytes. Nodavirus (NNV) infection elicited an up-regulation of crtam and cadm1a in brain and HK, appearing earlier in seabream than in seabass, which could explain the resistance of seabream to the development of nodavirus disease. In addition, they are up-regulated during the innate cell-mediated cytotoxic response in seabream but not in seabass. Altogether, our data seem to indicate that CRTAM is more related to the innate cytotoxicity in seabream and more in the specific and T cell-mediated cytotoxicity in seabass. Our results highlight the importance of CRTAM and CADM1 as important molecules in the activation of T lymphocytes in seabass and seabream, but further studies are needed.
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Affiliation(s)
- Miguel Ángel García-Álvarez
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain
| | - Carmen González-Fernández
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain
| | - María Ángeles Esteban
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain
| | - Alberto Cuesta
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain.
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Valsamidis MA, White DM, Kokkoris GD, Bakopoulos V. Immune response of European sea bass (Dicentrarchus labrax L.) against combination of antigens from three different pathogens. Vet Immunol Immunopathol 2023; 256:110535. [PMID: 36621058 DOI: 10.1016/j.vetimm.2022.110535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 12/12/2022] [Accepted: 12/13/2022] [Indexed: 12/24/2022]
Abstract
Three of the most important diseases of Mediterranean intensive European sea bass farming are, viral nervous necrosis (VNN) caused by the red grouper nervous necrosis virus (RGNNV) genotype of b-nodavirus, photobacteriosis caused by Photobacterium damselae subsp. piscicida (Phdp) and vibriosis caused mainly by the O1 serotype of Vibrio anguillarum (VaO1). Prevention against these diseases is performed through vaccination with a monovalent vaccine against the viral disease and, usually, with bivalent vaccines against the bacterial diseases. However, it is very difficult to program two vaccinations during the same season for the same fish stock and producers are forced to either vaccinate for the viral or the bacterial diseases or to perform double vaccination with both vaccines, without any prior knowledge on any interactions that may occur due to the plethora of antigens (Ag) injected. Ideally, therefore, a trivalent vaccine should be developed against all three diseases. The objective of this work was to analyse the immune response of sea bass against combinations of Ags from all three pathogens, namely viral particles, Phdp whole cells (WC), lipopolysaccharide (LPS), capsular polysaccharide (CPS) and extracellular products (ECPs) and VaO1 WC and ECPs in respect to the identification of any phenomena of immunodominance/immunosuppression between Ags with a view to select candidate Ags for inclusion in a trivalent vaccine formulation. Eight triplicate groups of fish were immunized with different combinations of the aforementioned Ags and another triplicate group served as negative control. Blood serum was isolated at various time-points post-immunization for the measurement of specific antibodies against each Ag and, in addition, leucocytes were isolated at day 29 post-immunization for analysis of various cellular activities. Results indicated that best levels of specific a-NNV virus antibodies (Abs) were produced when VaO1 ECPs were not included in the Ag combinations, in contrast to the leucocytes proliferation assay where best stimulation against NNV Ags was measured when VaO1 ECPs were present in Ag combinations. VaO1 ECPs apparently is a strong immunogen for both humoral and cellular responses but suppresses immunological reactions against the other Ags.VaO1 WC, Phdp LPS and ECPs raised good humoral immune responses in the groups with best responses against VNN Ags, but only VaO1 WC and Phdp ECPs provided good stimulation of leucocytes, with Phdp WC and CPS effecting either similar stimulation with untrained leucocytes (control groups) or down-stimulation. Results are discussed with a view to select Ags from all three pathogens for inclusion in trivalent vaccine against all three pathogens.
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Affiliation(s)
- Michail-Aggelos Valsamidis
- Department of Marine Sciences, School of The Environment, University of The Aegean, University Hill, Mytilene 81100, Lesvos, Greece.
| | - Daniella-Mari White
- Department of Marine Sciences, School of The Environment, University of The Aegean, University Hill, Mytilene 81100, Lesvos, Greece
| | - Giorgos D Kokkoris
- Department of Marine Sciences, School of The Environment, University of The Aegean, University Hill, Mytilene 81100, Lesvos, Greece
| | - Vasileios Bakopoulos
- Department of Marine Sciences, School of The Environment, University of The Aegean, University Hill, Mytilene 81100, Lesvos, Greece
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9
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Valero Y, Mercado L, Arizcun M, Cuesta A, Chaves-Pozo E. Priming European Sea Bass Female Broodstock Improves the Antimicrobial Immunity of Their Offspring. Animals (Basel) 2023; 13:ani13030415. [PMID: 36766303 PMCID: PMC9913748 DOI: 10.3390/ani13030415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 01/16/2023] [Accepted: 01/22/2023] [Indexed: 01/28/2023] Open
Abstract
Acquiring immunocompetence is essential in the development of fish embryos, as they are exposed to environmental pathogens even before they are fertilized. Despite the importance of the antimicrobial function as the first line of defense against foreign microorganisms, little knowledge is available about its role in larval development. In vertebrates, transgenerational immune priming influences the acquisition of immunocompetence of specimens, regulating the selective allocation of nongenetic resources to their progeny and modulating their development. In this work, we primed teleost European sea bass broodstock females with a viral protein expression vector in order to evaluate the innate immunity development of their offspring. Several antimicrobial functions, the pattern of expression of gene coding for different antimicrobial peptides (AMPs), and their protein levels, were evaluated in eggs and larvae during development. Our data determined the presence of antimicrobial proteins of maternal origin in eggs, and that female vaccination increases antimicrobial activities and the transcription and synthesis of AMPs during larval development.
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Affiliation(s)
- Yulema Valero
- Oceanographic Centre of Murcia, Spanish Institute of Oceanography, Spanish National Research Council, Carretera de la Azohía s/n, Puerto de Mazarrón, 30860 Murcia, Spain
- Grupo de Marcadores Inmunológicos, Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso 2362807, Chile
| | - Luis Mercado
- Grupo de Marcadores Inmunológicos, Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso 2362807, Chile
| | - Marta Arizcun
- Oceanographic Centre of Murcia, Spanish Institute of Oceanography, Spanish National Research Council, Carretera de la Azohía s/n, Puerto de Mazarrón, 30860 Murcia, Spain
| | - Alberto Cuesta
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence “Campus Mare Nostrum”, University of Murcia, 30100 Murcia, Spain
| | - Elena Chaves-Pozo
- Oceanographic Centre of Murcia, Spanish Institute of Oceanography, Spanish National Research Council, Carretera de la Azohía s/n, Puerto de Mazarrón, 30860 Murcia, Spain
- Correspondence: ; Tel.: +34-968153339; Fax: +34-968153934
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Serna-Duque JA, Cuesta A, Sánchez-Ferrer Á, Esteban MÁ. Two duplicated piscidin genes from gilthead seabream (Sparus aurata) with different roles in vitro and in vivo. FISH & SHELLFISH IMMUNOLOGY 2022; 127:730-739. [PMID: 35835383 DOI: 10.1016/j.fsi.2022.07.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 07/04/2022] [Accepted: 07/06/2022] [Indexed: 06/15/2023]
Abstract
From the discovery of pleurocidin in skin mucus of winter flounder, many new related sequences have been found, forming a fish-exclusive family of antimicrobial peptides (AMP) called piscidin. Their mature peptides have a broad-spectrum antimicrobial activity and can be involved in the innate immune response. In the present work, two paralogous tripartite piscidin genes are formally described for the first time in gilthead seabream (Sparus aurata), an important marine farmed fish. Gene synteny and protein phylogeny clearly indicated a massive pisc gene expansion in a cluster of the chromosome 22 as well as a special evolution of piscidin in gilthead seabream compared to the rest of piscidins studied in other fish species. Despite being highly similar genes, they show totally different expression patterns in tissues and head-kidney leucocytes under both naïve and Vibrio/nodavirus-stimulated conditions. Moreover, these paralogous genes coded very different proteins according to their physicochemical properties. In this way, these piscidin genes have distinct roles not only related to their microbicide activity but also to their immune modulation. In addition, the present study improves the knowledge of duplication of AMP genes and adaptative diversification of teleost immune system.
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Affiliation(s)
- Jhon A Serna-Duque
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, 30100, Murcia, Spain
| | - Alberto Cuesta
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, 30100, Murcia, Spain
| | - Álvaro Sánchez-Ferrer
- Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Murcia, 30100, Murcia, Spain
| | - M Ángeles Esteban
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, 30100, Murcia, Spain.
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11
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García-Álvarez MÁ, Arizcun M, Chaves-Pozo E, Cuesta A. Profile of Innate Immunity in Gilthead Seabream Larvae Reflects Mortality upon Betanodavirus Reassortant Infection and Replication. Int J Mol Sci 2022; 23:ijms23095092. [PMID: 35563482 PMCID: PMC9105140 DOI: 10.3390/ijms23095092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 04/28/2022] [Accepted: 04/29/2022] [Indexed: 12/10/2022] Open
Abstract
Historically, gilthead seabream (Sparus aurata) has been considered a fish species resistant to nervous necrosis virus (NNV) disease. Nevertheless, mortality in seabream hatcheries, associated with typical clinical signs of the viral encephalopathy and retinopathy (VER) disease has been confirmed to be caused by RGNNV/SJNNV reassortants. Because of this, seabream larvae at 37 and 86 days post-hatching (dph) were infected by immersion with RGNNV/SJNNV and SJNNV/RGNNV reassortants under laboratory conditions, and mortality, viral replication and immunity were evaluated. Our results show that gilthead seabream larvae, mainly those at 37 dph, are susceptible to infection with both NNV reassortant genotypes, with the highest impact from the RGNNV/SJNNV reassortant. In addition, viral replication occurs at both ages (37 and 86 dph) but the recovery of infective particles was only confirmed in 37 dph larvae,; this value was also highest with the RGNNV/SJNNV reassortant. Larvae immunity, including the expression of antiviral, inflammatory and cell-mediated cytotoxicity genes, was affected by NNV infection. Levels of the natural killer lysin (Nkl) peptide were increased in SJNNV/RGNNV-infected larvae of 37 dph, though hepcidin was not. Our results demonstrate that the seabream larvae are susceptible to both NNV reassortants, though mainly to RGNNV/SJNNV, in an age-dependent manner.
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Affiliation(s)
- Miguel Ángel García-Álvarez
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence “Campus Mare Nostrum”, University of Murcia, 30100 Murcia, Spain;
| | - Marta Arizcun
- Oceanographic Center of Murcia, Spanish Institute of Oceanography, Spanish National Research Council (IEO-CSIC), Carretera de la Azohía s/n. Puerto de Mazarrón, 30860 Murcia, Spain; (M.A.); (E.C.-P.)
| | - Elena Chaves-Pozo
- Oceanographic Center of Murcia, Spanish Institute of Oceanography, Spanish National Research Council (IEO-CSIC), Carretera de la Azohía s/n. Puerto de Mazarrón, 30860 Murcia, Spain; (M.A.); (E.C.-P.)
| | - Alberto Cuesta
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence “Campus Mare Nostrum”, University of Murcia, 30100 Murcia, Spain;
- Correspondence:
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12
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Early Immune Modulation in European Seabass (Dicentrarchus labrax) Juveniles in Response to Betanodavirus Infection. FISHES 2022. [DOI: 10.3390/fishes7020063] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The early host–pathogen interaction between European seabass (Dicentrarchus labrax) and Betanodavirus was examined by using juvenile fish infected intramuscularly with RGNNV (red-spotted grouper nervous necrosis virus). The time course selected for sampling (0–144 h post-infection (hpi)) covered the early stages of infection, with hematological, antioxidant and immunological responses examined. Early activation of the host’s immune system was seen in the first few hours post-infection (6 to 9 hpi), as evidenced by an increase in tnfα, cd28 and c3 expression in the head kidney of infected fish. Most hematological parameters that were examined showed significant differences between sampling times, including differences in the number of thrombocytes and various leukocyte populations. The plasma lysozyme concentration decreased significantly over the course of the trial, and most antioxidant parameters examined in the liver showed significant differences over the infection period. At 144 hpi, peak expression of tnfα and il-1β coincided with the appearance of disease symptoms, peak levels of virus in the brain and high levels of fish mortality. The results of the study show the importance of analyzing the early interactions between European seabass and Betanodavirus to establish early indicators of infection to prevent more severe outcomes of the infection from occurring.
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13
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Falco A, Bello-Perez M, Díaz-Puertas R, Mold M, Adamek M. Update on the Inactivation Procedures for the Vaccine Development Prospects of a New Highly Virulent RGNNV Isolate. Vaccines (Basel) 2021; 9:vaccines9121441. [PMID: 34960187 PMCID: PMC8705346 DOI: 10.3390/vaccines9121441] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 11/30/2021] [Accepted: 12/03/2021] [Indexed: 01/01/2023] Open
Abstract
Viral nervous necrosis (VNN) caused by the nervous necrosis virus (NNV) affects a broad range of primarily marine fish species, with mass mortality rates often seen among larvae and juveniles. Its genetic diversification may hinder the effective implementation of preventive measures such as vaccines. The present study describes different inactivation procedures for developing an inactivated vaccine against a new NNV isolate confirmed to possess deadly effects upon the European seabass (Dicentrarchus labrax), an important Mediterranean farmed fish species that is highly susceptible to this disease. First, an NNV isolate from seabass adults diagnosed with VNN was rescued and the sequences of its two genome segments (RNA1 and RNA2) were classified into the red-spotted grouper NNV (RGNNV) genotype, closely clustering to the highly pathogenic 283.2009 isolate. The testing of different inactivation procedures revealed that the virus particles of this isolate showed a marked resistance to heat (for at least 60 °C for 120 min with and without 1% BSA) but that they were fully inactivated by 3 mJ/cm2 UV-C irradiation and 24 h 0.2% formalin treatment, which stood out as promising NNV-inactivation procedures for potential vaccine candidates. Therefore, these procedures are feasible, effective, and rapid response strategies for VNN control in aquaculture.
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Affiliation(s)
- Alberto Falco
- Institute of Research, Development and Innovation in Healthcare Biotechnology in Elche (IDiBE), Miguel Hernández University, 03202 Elche, Spain; (M.B.-P.); (R.D.-P.)
- Correspondence:
| | - Melissa Bello-Perez
- Institute of Research, Development and Innovation in Healthcare Biotechnology in Elche (IDiBE), Miguel Hernández University, 03202 Elche, Spain; (M.B.-P.); (R.D.-P.)
| | - Rocío Díaz-Puertas
- Institute of Research, Development and Innovation in Healthcare Biotechnology in Elche (IDiBE), Miguel Hernández University, 03202 Elche, Spain; (M.B.-P.); (R.D.-P.)
| | - Matthew Mold
- The Birchall Centre, Lennard-Jones Laboratories, Keele University, Staffordshire ST5 5BG, UK;
| | - Mikolaj Adamek
- Fish Disease Research Unit, Institute for Parasitology, University of Veterinary Medicine, 30559 Hannover, Germany;
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14
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Valero Y, González-Fernández C, Cárdenas C, Guzmán F, León R, Cuesta A. NK-lysin peptides ameliorate viral encephalopathy and retinopathy disease signs and provide partial protection against nodavirus infection in European sea bass. Antiviral Res 2021; 192:105104. [PMID: 34087253 DOI: 10.1016/j.antiviral.2021.105104] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 05/22/2021] [Accepted: 05/27/2021] [Indexed: 02/09/2023]
Abstract
Antimicrobial peptides (AMP) comprise a wide range of small molecules with direct antibacterial activity and immunostimulatory role and are proposed as promising substitutes of the antibiotics. Additionally, they also exert a role against other pathogens such as viruses and fungi less evaluated. NK-lysin, a human granulysin orthologue, possess a double function, taking part in the innate immunity as AMP and also as direct effector in the cell-mediated cytotoxic (CMC) response. This molecule is suggested as a pivotal molecule involved in the defence upon nervous necrosis virus (NNV), an epizootic virus provoking serious problems in welfare and health status in Asian and Mediterranean fish destined to human consumption. Having proved that NK-lysin derived peptides (NKLPs) have a direct antiviral activity against NNV in vitro, we aimed to evaluate their potential use as a prophylactic treatment for European sea bass (Dicentrarchus labrax), one of the most susceptible cultured-fish species. Thus, intramuscular injection of synthetic NKLPs resulted in a very low transcriptional response of some innate and adaptive immune markers. However, the injection of NKLPs ameliorated disease signs and increased fish survival upon challenge with pathogenic NNV. Although NKLPs showed promising results in treatments against NNV, more efforts are needed to understand their mechanisms of action and their applicability to the aquaculture industry.
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Affiliation(s)
- Yulema Valero
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain; Departamento de Microbiología y Parasitología, Instituto de Acuicultura, Universidade de Santiago de Compostela, Campus Vida, Santiago de Compostela, Spain
| | - Carmen González-Fernández
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain
| | - Constanza Cárdenas
- Núcleo Biotecnología Curauma (NBC), Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Fanny Guzmán
- Núcleo Biotecnología Curauma (NBC), Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Rosa León
- Laboratorio de Bioquímica, Facultad de Ciencias Experimentales, Campus de Excelencia Internacional Del Mar (CEIMAR), Universidad de Huelva, 2110, Huelva, Spain
| | - Alberto Cuesta
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain.
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15
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González-Fernández C, Esteban MA, Cuesta A. Molecular characterization of the T cell costimulatory receptors CD28 and CTLA4 in the European sea bass. FISH & SHELLFISH IMMUNOLOGY 2021; 109:106-115. [PMID: 33348036 DOI: 10.1016/j.fsi.2020.12.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 11/16/2020] [Accepted: 12/15/2020] [Indexed: 06/12/2023]
Abstract
For the activation of T cells, it is necessary the specific recognition of the peptide by the T cell receptors (TCR) in the surface of antigen-presenting cells (APCs) and additional signals delivered by costimulatory receptors. In fish, knowledge about the presence of these costimulatory signals is limited and functional evidence almost absent. Thus, in this study, we have identified the stimulatory CD28 and the inhibitory cytotoxic T-lymphocyte-associated protein 4 (CTLA4) coreceptors in the European sea bass (Dicentrarchus labrax), and evaluated their transcription. In parallel, the transcription encoding for the T cell markers CD8α and CD4 was also evaluated. Both coreceptors showed the canonical architecture including a signal peptide, an immunoglobulin domain, a transmembrane region and a cytosolic tail. Protein predictions and phylogenetic tree identify them as true mammalian orthologues of CD28 and CTLA4. We found these genes constitutively expressed in all studied organs of European sea bass with high expression in lymphoid organs (thymus, spleen and head-kidney) and liver. The molecular expression pattern of these genes was up-regulated in head-kidney leucocytes stimulated with T mitogens as concanavalin A and phytohemagglutinin (PHA), but not with the B cell mitogen lipopolysaccharide (LPS). Fish challenged with nodavirus (NNV) evidenced a differential and opposing regulation of the cd28 and ctla4 transcription levels in the brain, the target organ for viral replication, and head-kidney. While cd28 transcription tends to decrease over the infection time in both organs the expression of the ctla4 gene tends to increase. Interestingly, the coreceptor expression is highly and significantly correlated to the transcription of the T cell markers. Our results highlight the important role of CD28 and CTLA4 as costimulatory receptors of T cells in European sea bass but further studies are deserved.
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Affiliation(s)
- Carmen González-Fernández
- Immunobiotechnology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain
| | - María A Esteban
- Immunobiotechnology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain
| | - Alberto Cuesta
- Immunobiotechnology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain.
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16
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Moreno P, Gemez-Mata J, Garcia-Rosado E, Bejar J, Labella AM, Souto S, Alonso MC. Differential immunogene expression profile of European sea bass (Dicentrarchus labrax, L.) in response to highly and low virulent NNV. FISH & SHELLFISH IMMUNOLOGY 2020; 106:56-70. [PMID: 32702480 DOI: 10.1016/j.fsi.2020.06.052] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 06/25/2020] [Accepted: 06/26/2020] [Indexed: 06/11/2023]
Abstract
European sea bass is highly susceptible to the nervous necrosis virus, RGNNV genotype, whereas natural outbreaks caused by the SJNNV genotype have not been recorded. The onset and severity of an infectious disease depend on pathogen virulence factors and the host immune response. The importance of RGNNV capsid protein amino acids 247 and 270 as virulence factors has been previously demonstrated in European sea bass; however, sea bass immune response against nodaviruses with different levels of virulence has been poorly characterized. Knowing the differences between the immune response against both kinds of isolates may be key to get more insight into the host mechanisms responsible for NNV virulence. For this reason, this study analyses the transcription of immunogenes differentially expressed in European sea bass inoculated with nodaviruses with different virulence: a RGNNV virus obtained by reverse genetics (rDl956), highly virulent to sea bass, and a mutated virus (Mut247+270Dl956, RGNNV virus displaying SJNNV-type amino acids at positions 247 and 270 of the capsid protein), presenting lower virulence. This study has been performed in brain and head kidney, and the main differences between the immunogene responses triggered by both viruses have been observed in brain. The immunogene response in this organ is stronger after inoculation with the most virulent virus, and the main differences involved genes related with IFN I system, inflammatory response, cell-mediated response, and apoptosis. The lower virulence of Mut247+270Dl956 to European sea bass can be associated with a delayed IFN I response, as well as an early and transitory inflammation and cell-mediated responses, suggesting that those can be pivotal elements in controlling the viral infection, and therefore, their functional activity could be analysed in future studies. In addition, this study supports the role of capsid amino acids at positions 247 and 270 as important determinants of RGNNV virulence to European sea bass.
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Affiliation(s)
- Patricia Moreno
- Universidad de Málaga, Instituto de Biotecnología y Desarrollo Azul, IBYDA, Departamento de Microbiología, Facultad de Ciencias, 29071, Málaga, Spain
| | - Juan Gemez-Mata
- Universidad de Málaga, Instituto de Biotecnología y Desarrollo Azul, IBYDA, Departamento de Microbiología, Facultad de Ciencias, 29071, Málaga, Spain
| | - Esther Garcia-Rosado
- Universidad de Málaga, Instituto de Biotecnología y Desarrollo Azul, IBYDA, Departamento de Microbiología, Facultad de Ciencias, 29071, Málaga, Spain
| | - Julia Bejar
- Universidad de Málaga, Instituto de Biotecnología y Desarrollo Azul, IBYDA, Departamento de Biología Celular, Genética y Fisiología, Facultad de Ciencias, 29071, Málaga, Spain
| | - Alejandro M Labella
- Universidad de Málaga, Instituto de Biotecnología y Desarrollo Azul, IBYDA, Departamento de Microbiología, Facultad de Ciencias, 29071, Málaga, Spain
| | - Sandra Souto
- Departamento de Microbiología y Parasitología, Instituto de Acuicultura, Universidad de Santiago de Compostela, Santiago de Compostela, Spain
| | - M Carmen Alonso
- Universidad de Málaga, Instituto de Biotecnología y Desarrollo Azul, IBYDA, Departamento de Microbiología, Facultad de Ciencias, 29071, Málaga, Spain.
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17
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Ruiz-Palacios M, Esteban MÁ, Cuesta A. Establishment of a brain cell line (SaB-1) from gilthead seabream and its application to fish virology. FISH & SHELLFISH IMMUNOLOGY 2020; 106:161-166. [PMID: 32771610 DOI: 10.1016/j.fsi.2020.07.065] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 07/28/2020] [Accepted: 07/30/2020] [Indexed: 06/11/2023]
Abstract
Gilthead seabream (Sparus aurata) is among the most important cultured fish species in the Mediterranean area and pathogen diseases one of the bottlenecks to the aquaculture sector. For this reason, generation of laboratory tools for diagnostic and research applications would be beneficial to improve the seabream aquaculture. In this sense, we aimed to generate a seabream cell line for biological studies. Thus, we have obtained a brain-derived cell line (SaB-1) that is continuously growing for more than 4 years. Cellular characterization of the SaB-1 cells shows that they express both neural and glial cell markers, suggesting they are neural-stem cells, have a neuron-like morphology and show a rapid growth in culture. We evaluated their susceptibility to the main fish viruses: nervous necrosis virus (NNV), spring viremia carp virus (SVCV), infectious pancreatic necrosis virus (IPNV) and viral haemorrhagic septicaemia virus (VHSV). SaB-1 cells are susceptible to all the tested viruses. In addition, the transcription of genes related to the type I interferon (IFN) is greatly up-regulated by the NNV infection whilst the viral infection with SVCV, IPNV or VHSV failed to do so. These data demonstrate that the seabream SaB-1 cell line is continuous, stable and could be useful, at least, for fish virology and immunity applications.
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Affiliation(s)
- María Ruiz-Palacios
- Immunobiology for Aquaculture Group, Department of Cellular Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain
| | - M Ángeles Esteban
- Immunobiology for Aquaculture Group, Department of Cellular Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain
| | - Alberto Cuesta
- Immunobiology for Aquaculture Group, Department of Cellular Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain.
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18
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Potential Involvement of lncRNAs in the Modulation of the Transcriptome Response to Nodavirus Challenge in European Sea Bass ( Dicentrarchus labrax L.). BIOLOGY 2020; 9:biology9070165. [PMID: 32679770 PMCID: PMC7407339 DOI: 10.3390/biology9070165] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 07/09/2020] [Accepted: 07/13/2020] [Indexed: 12/14/2022]
Abstract
Long noncoding RNAs (lncRNAs) are being increasingly recognised as key modulators of various biological mechanisms, including the immune response. Although investigations in teleosts are still lagging behind those conducted in mammals, current research indicates that lncRNAs play a pivotal role in the response of fish to a variety of pathogens. During the last several years, interest in lncRNAs has increased considerably, and a small but notable number of publications have reported the modulation of the lncRNA profile in some fish species after pathogen challenge. This study was the first to identify lncRNAs in the commercial species European sea bass. A total of 12,158 potential lncRNAs were detected in the head kidney and brain. We found that some lncRNAs were not common for both tissues, and these lncRNAs were located near coding genes that are primarily involved in tissue-specific processes, reflecting a degree of cellular specialisation in the synthesis of lncRNAs. Moreover, lncRNA modulation was analysed in both tissues at 24 and 72 h after infection with nodavirus. Enrichment analysis of the neighbouring coding genes of the modulated lncRNAs revealed many terms related to the immune response and viral infectivity but also related to the stress response. An integrated analysis of the lncRNAs and coding genes showed a strong correlation between the expression of the lncRNAs and their flanking coding genes. Our study represents the first systematic identification of lncRNAs in European sea bass and provides evidence regarding the involvement of these lncRNAs in the response to nodavirus.
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19
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Lama R, Pereiro P, Valenzuela-Muñoz V, Gallardo-Escárate C, Tort L, Figueras A, Novoa B. RNA-Seq analysis of European sea bass (Dicentrarchus labrax L.) infected with nodavirus reveals powerful modulation of the stress response. Vet Res 2020; 51:64. [PMID: 32398117 PMCID: PMC7218500 DOI: 10.1186/s13567-020-00784-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 04/16/2020] [Indexed: 12/15/2022] Open
Abstract
Nodavirus, or nervous necrosis virus (NNV), is the causative agent of viral encephalopathy and retinopathy (VER), a severe disease affecting numerous fish species worldwide. European sea bass, a cultured species of great economic importance, is highly susceptible to the disease. To better understand the response of this organism to NNV, we conducted RNA-Seq analysis of the brain and head kidney from experimentally infected and uninfected sea bass juveniles at 24 and 72 hours post-infection (hpi). Contrary to what was expected, we observed modest modulation of immune-related genes in the brain, the target organ of this virus, and some of these genes were even downregulated. However, genes involved in the stress response showed extremely high modulation. Accordingly, the genes encoding the enzymes implicated in the synthesis of cortisol were almost the only overexpressed genes in the head kidney at 24 hpi. This stress response was attenuated after 72 h in both tissues, and a progressive immune response against the virus was mounted. Moreover, experiments were conducted to determine how stress activation could impact NNV replication. Our results show the complex interplay between viral activity, the stress reaction and the immune response.
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Affiliation(s)
- Raquel Lama
- Institute of Marine Research (IIM), National Research Council (CSIC), Eduardo Cabello, 6, 36208, Vigo, Spain
| | - Patricia Pereiro
- Institute of Marine Research (IIM), National Research Council (CSIC), Eduardo Cabello, 6, 36208, Vigo, Spain.,Laboratory of Biotechnology and Aquatic Genomics, Interdisciplinary Center for Aquaculture Research (INCAR), University of Concepción, P.O. Box 160, Concepción, Chile
| | - Valentina Valenzuela-Muñoz
- Laboratory of Biotechnology and Aquatic Genomics, Interdisciplinary Center for Aquaculture Research (INCAR), University of Concepción, P.O. Box 160, Concepción, Chile
| | - Cristian Gallardo-Escárate
- Laboratory of Biotechnology and Aquatic Genomics, Interdisciplinary Center for Aquaculture Research (INCAR), University of Concepción, P.O. Box 160, Concepción, Chile
| | - Lluis Tort
- Department of Cell Biology, Physiology and Immunology, Autonomous University of Barcelona, 08193, Barcelona, Spain
| | - Antonio Figueras
- Institute of Marine Research (IIM), National Research Council (CSIC), Eduardo Cabello, 6, 36208, Vigo, Spain
| | - Beatriz Novoa
- Institute of Marine Research (IIM), National Research Council (CSIC), Eduardo Cabello, 6, 36208, Vigo, Spain.
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20
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Valero Y, Chaves-Pozo E, Cuesta A. NK-lysin is highly conserved in European sea bass and gilthead seabream but differentially modulated during the immune response. FISH & SHELLFISH IMMUNOLOGY 2020; 99:435-441. [PMID: 32088283 DOI: 10.1016/j.fsi.2020.02.049] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 02/13/2020] [Accepted: 02/18/2020] [Indexed: 06/10/2023]
Abstract
Fish NK-lysin (NKL), an orthologous to human granulysin, exerts a dual role as an antimicrobial peptide (AMP) and as a direct executor of T cytotoxic and natural killer cells during the cell-mediated cytotoxic (CMC) response. Although its best-known function is as AMP against bacteria, recent studies point to a special role of NKL in antiviral responses. Nodavirus (NNV) is a spreading threat in Mediterranean aquaculture. In this study, we have identified and compared the expression pattern of European sea bass and gilthead seabream NKL and evaluated its transcription in different tissues and its regulation in head-kidney leucocyte (HKLs) stimulated in vitro with different immunostimulants, under CMC response and upon an in vivo infection with NNV. Our results showed that nkl transcription is highly expressed in spleen, thymus and skin with species-specific differences. Interestingly, the expression pattern in both species was very different upon treatment. While sea bass nkl transcription was increased in HKLs by the T mitogen phytohemagglutinin all the stimulators inhibited it in seabream HKLs. Similar results occurred in NNV-infected fish where the transcription was increased in sea bass tissues and down-regulated in seabream. Curiously, during CMC assays, nkl transcription was significantly increased in seabream HKLs against NNV-infected fish cell lines but this was not observed in sea bass leucocytes. The potential role of NKL as CMC effector molecule or as AMP in fish will be discussed.
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Affiliation(s)
- Yulema Valero
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain; Departamento de Microbiología y Parasitología, Instituto de Acuicultura, Universidade de Santiago de Compostela, Campus Vida, Santiago de Compostela, Spain; Oceanographic Centre of Murcia, Spanish Institute of Oceanography (IEO), Carretera de la Azohía s/n, 30860, Puerto de Mazarrón, Murcia, Spain
| | - Elena Chaves-Pozo
- Oceanographic Centre of Murcia, Spanish Institute of Oceanography (IEO), Carretera de la Azohía s/n, 30860, Puerto de Mazarrón, Murcia, Spain
| | - Alberto Cuesta
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain.
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21
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Identification and Regulation of Interleukin-17 (IL-17) Family Ligands in the Teleost Fish European Sea Bass. Int J Mol Sci 2020; 21:ijms21072439. [PMID: 32244562 PMCID: PMC7178287 DOI: 10.3390/ijms21072439] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 03/23/2020] [Accepted: 03/30/2020] [Indexed: 12/19/2022] Open
Abstract
Interleukin-17 (IL-17) cytokine comprises a family of six ligands in mammals with proinflammatory functions, having an important role in autoimmune disorders and against bacterial, viral, and fungal pathogens. While IL-17A and IL-17F ligands are mainly produced by Th cells (Th17 cells), the rest of the ligands are expressed by other immune and non-immune cells and have different functions. The identification of IL-17 ligands in fish has revealed the presence of six members, counterparts to mammalian ones, and a teleost-specific form, the fish IL-17N. However, tissue distribution, the regulation of gene expression, and scarce bioactivity assays point to similar functions compared to mammalian ones, though this yet to be investigated and confirmed. Thus, we have identified seven IL-17 ligands in the teleost European sea bass (Dicentrarchus labrax), for the first time, corresponding to IL-17A/F1, IL-17A/F2, IL-17A/F3, IL-17C1, IL-17C2, IL-17D, and IL-17N, according to the predicted protein sequences and phylogenetic analysis. They are constitutively and widely transcribed in sea bass tissues, with some of them being mainly expressed in the thymus, brain or intestine. Upon in vitro stimulation of head-kidney leucocytes, the mRNA levels of all sea bass IL-17 ligands were up-regulated by phytohemagglutinin treatment, a well-known T cell mitogen, suggesting a major expression in T lymphocytes. By contrast, the infection of sea bass juveniles with nodavirus (NNV), a very pathogenic virus for this fish species, resulted in the up-regulation of the transcription of IL-17C1 in the head-kidney and of IL-17C1 and IL-17D in the brain, the target tissue for NNV replication. By contrast, NNV infection led to a down-regulated transcription of IL-17A/F1, IL-17A/F2, IL-17C1, IL-17C2, and IL-17D in the head-kidney and of IL-17A/F1 and IL-17A/F3 in the brain. The data are discussed accordingly with the IL-17 ligand expression and the immune response under the different situations tested.
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Ruiz-Palacios M, Almeida M, Martins MA, Oliveira M, Esteban MÁ, Cuesta A. Establishment of a brain cell line (FuB-1) from mummichog (Fundulus heteroclitus) and its application to fish virology, immunity and nanoplastics toxicology. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 708:134821. [PMID: 31791770 DOI: 10.1016/j.scitotenv.2019.134821] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 10/02/2019] [Accepted: 10/03/2019] [Indexed: 06/10/2023]
Abstract
The marine fish mummichog (Fundulus heteroclitus), extensively used as research model, including in ecotoxicology, for over a century has been surpassed by other fish species. This fact may be associated with the lack of cell lines from this species, excellent models for the comprehension of fish physiology, immunology, toxicology and virology, that contribute to the reduction in the number of animals used in research. We have generated, for the first time, a brain-derived cell line from mummichog, FuB-1, and evaluated its application to the fields of fish virology, immunity and toxicology. First, FuB-1 cells show epithelial morphology and neural stem/astroglial origin. Secondly, FuB-1 cells effectively supports the replication of both spring viremia carp (SVCV) and infectious pancreatic necrosis (IPNV) viruses, but not nodavirus (NNV), indicating its potential use for fish virology. Related to this, FuB-1 cells infected with NNV up-regulate the transcription of genes related to the antiviral immune response, leading to cell resistance; while they are unaltered when infected with IPNV and SVCV, facilitating viral replication. Finally, FuB-1 cells were used for toxicological purposes and we demonstrated that exposure to either polystyrene nanoplastics (PS-100) or several human-usage pharmaceuticals are cytotoxic. Additionally, PS-100 particles increase the antioxidant catalase and glutathione S-transferase activities and decrease the total non-protein thiols in FuB-1 cells. However, PS-100 particles are able to reduce the cytotoxic effects induced by the pharmaceuticals. In conclusion, we have generated a cell line from mummichog, which might represent a valuable model for fish studies in the fields of virology, immunology and toxicology.
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Affiliation(s)
- María Ruiz-Palacios
- Fish Innate Immune System Group, Department of Cellular Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100 Murcia, Spain
| | - Mónica Almeida
- Department of Biology & CESAM, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Manuel A Martins
- Department of Biology & CESAM, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Miguel Oliveira
- Department of Biology & CESAM, University of Aveiro, 3810-193 Aveiro, Portugal
| | - María Ángeles Esteban
- Fish Innate Immune System Group, Department of Cellular Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100 Murcia, Spain
| | - Alberto Cuesta
- Fish Innate Immune System Group, Department of Cellular Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100 Murcia, Spain.
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Betanodavirus and VER Disease: A 30-year Research Review. Pathogens 2020; 9:pathogens9020106. [PMID: 32050492 PMCID: PMC7168202 DOI: 10.3390/pathogens9020106] [Citation(s) in RCA: 113] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 01/22/2020] [Accepted: 02/04/2020] [Indexed: 12/18/2022] Open
Abstract
The outbreaks of viral encephalopathy and retinopathy (VER), caused by nervous necrosis virus (NNV), represent one of the main infectious threats for marine aquaculture worldwide. Since the first description of the disease at the end of the 1980s, a considerable amount of research has gone into understanding the mechanisms involved in fish infection, developing reliable diagnostic methods, and control measures, and several comprehensive reviews have been published to date. This review focuses on host–virus interaction and epidemiological aspects, comprising viral distribution and transmission as well as the continuously increasing host range (177 susceptible marine species and epizootic outbreaks reported in 62 of them), with special emphasis on genotypes and the effect of global warming on NNV infection, but also including the latest findings in the NNV life cycle and virulence as well as diagnostic methods and VER disease control.
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Valero Y, Arizcun M, Cortés J, Ramírez-Cepeda F, Guzmán F, Mercado L, Esteban MÁ, Chaves-Pozo E, Cuesta A. NK-lysin, dicentracin and hepcidin antimicrobial peptides in European sea bass. Ontogenetic development and modulation in juveniles by nodavirus. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2020; 103:103516. [PMID: 31593708 DOI: 10.1016/j.dci.2019.103516] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 10/03/2019] [Accepted: 10/03/2019] [Indexed: 05/06/2023]
Abstract
Antimicrobial peptides (AMPs) are considered to be amongst the most powerful tools for the fight against pathogens in fish, since they form part of the innate immune response, which is especially vital in eggs and early larval stages, when the immune system is developing. The fish responsible for a large part of the profits in Mediterranean aquaculture is European sea bass (Dicentrarchus labrax), a species greatly susceptible to nodavirus (NNV), especially in the larval and juvenile stages. In this work, polyclonal antibodies were developed and used to detect and quantify NK-lysin, dicentracin and hepcidin AMPs in European sea bass eggs and during larval development, as well as to evaluate their regulation in juvenile specimens upon NNV infection. Basal and detectable levels of all the AMPs studied were present in eggs, confirming the maternal transfer of peptides, which increased in one or two waves during larval development up to 69 days post-fertilization. After NNV infection, the mRNA of all the AMPs analysed was up-regulated five days after infection in most of the tissues, whilst peptide quantification of all three AMPs decreased in the brain, the target tissue for NNV, but increased in the head-kidney 5 days after infection. Further research should be carried out to ascertain the role of AMPs in fish innate immunity and to understand how NNV evades the immune response to be disseminated.
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Affiliation(s)
- Yulema Valero
- Oceanographic Centre of Murcia, Spanish Institute of Oceanography (IEO), Carretera de la Azohía S/n, 30860, Puerto de Mazarrón, Murcia, Spain; Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain; Grupo de Marcadores Inmunológicos, Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Marta Arizcun
- Oceanographic Centre of Murcia, Spanish Institute of Oceanography (IEO), Carretera de la Azohía S/n, 30860, Puerto de Mazarrón, Murcia, Spain
| | - Jimena Cortés
- Grupo de Marcadores Inmunológicos, Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Felipe Ramírez-Cepeda
- Grupo de Marcadores Inmunológicos, Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Fanny Guzmán
- Grupo de Marcadores Inmunológicos, Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Luis Mercado
- Grupo de Marcadores Inmunológicos, Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - M Ángeles Esteban
- Oceanographic Centre of Murcia, Spanish Institute of Oceanography (IEO), Carretera de la Azohía S/n, 30860, Puerto de Mazarrón, Murcia, Spain
| | - Elena Chaves-Pozo
- Oceanographic Centre of Murcia, Spanish Institute of Oceanography (IEO), Carretera de la Azohía S/n, 30860, Puerto de Mazarrón, Murcia, Spain
| | - Alberto Cuesta
- Oceanographic Centre of Murcia, Spanish Institute of Oceanography (IEO), Carretera de la Azohía S/n, 30860, Puerto de Mazarrón, Murcia, Spain.
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Miccoli A, Saraceni PR, Scapigliati G. Vaccines and immune protection of principal Mediterranean marine fish species. FISH & SHELLFISH IMMUNOLOGY 2019; 94:800-809. [PMID: 31580938 DOI: 10.1016/j.fsi.2019.09.065] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 09/25/2019] [Accepted: 09/28/2019] [Indexed: 06/10/2023]
Abstract
This review describes and summarizes the knowledge on established and experimental vaccines developed against viral and bacterial pathologies affecting the most important farmed marine finfish species present in the Mediterranean area, namely European seabass Dicentrarchus labrax, sea bream Sparus aurata, turbot Psetta maxima and meagre Argyrosomus regius. The diseases that have been recorded in seabass, sea bream and meagre are caused by bacteria Vibrio anguillarum, Photobacterium damselae, Tenacibaculum maritimum as well as by viruses such as Viral Encephalopathy and Retinopathy/Viral Nervous Necrosis and Lymphocystic disease. The main pathologies of turbot are instead bacteriosis provoked by Tenacibaculum maritimum, Aeromonas sp. and Vibrio anguillarum, and virosis by viral hemorrhagic septicaemia virus. Some vaccines have been optimized and are now regularly available for the majority of the above-mentioned pathogens. A measurable immune protection has been conferred principally against Vibrio anguillarum, Photobacterium damselae sub. piscicida and VER/VNN.
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Affiliation(s)
- A Miccoli
- Department for Innovative Biology, Agro-industry and Forestry, University of Tuscia. Largo Dell'Università, 01100, Viterbo, Italy
| | - P R Saraceni
- Department for Innovative Biology, Agro-industry and Forestry, University of Tuscia. Largo Dell'Università, 01100, Viterbo, Italy
| | - G Scapigliati
- Department for Innovative Biology, Agro-industry and Forestry, University of Tuscia. Largo Dell'Università, 01100, Viterbo, Italy.
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Chaves-Pozo E, Valero Y, Lozano MT, Rodríguez-Cerezo P, Miao L, Campo V, Esteban MA, Cuesta A. Fish Granzyme A Shows a Greater Role Than Granzyme B in Fish Innate Cell-Mediated Cytotoxicity. Front Immunol 2019; 10:2579. [PMID: 31736981 PMCID: PMC6834543 DOI: 10.3389/fimmu.2019.02579] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 10/17/2019] [Indexed: 11/17/2022] Open
Abstract
Granzymes (Gzm) are serine proteases, contained into the secretory granules of cytotoxic cells, responsible for the cell-mediated cytotoxicity (CMC) against tumor cells and intracellular pathogens such as virus and bacteria. In fish, they have received little attention to their existence, classification or functional characterization. Therefore, we aimed to identify and evaluate their functional and transcriptomic relevance in the innate CMC activity of two relevant teleost fish species, gilthead seabream and European sea bass. Afterwards, we wanted to focus on their regulation upon nodavirus (NNV) infection, a virus that causes great mortalities to sea bass specimens while seabream is resistant. In this study, we have identified genes encoding GzmA and GzmB in both seabream and sea bass, as well as GzmM in seabream, which showed good phylogenetic relation to their mammalian orthologs. In addition, we found enzymatic activity related to tryptase (GzmA and/or GzmK), aspartase (GzmB), metase (GzmM), or chymase (GzmH) in resting head-kidney leucocytes (HKLs), with the following order of activity: GzmA/K ~ GzmM >> GzmH >>> GzmB. In addition, during innate CMC assays consisting on HKLs exposed to either mock- or NNV-infected target cells, though all the granzyme transcripts were increased only the tryptase activity did. Thus, our data suggest a high functional activity of GzmA/K in the innate CMC and a marginal one for GzmB. Moreover, GzmB activity was detected into target cells during the CMC assays. However, the percentage of target cells with GzmB activity after the CMC assays was about 10-fold lower than the death target cells, demonstrating that GzmB is not the main inductor of cell death. Moreover, in in vivo infection with NNV, gzm transcription is differently regulated depending on the fish species, genes and tissues. However, the immunohistochemistry study revealed an increased number of GzmB stained cells and areas in the brain of seabream after NNV infection, which was mainly associated with the lesions detected. Further studies are needed to ascertain the molecular nature, biological function and implication of fish granzymes in the CMC activity, and in the antiviral defense in particular.
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Affiliation(s)
- Elena Chaves-Pozo
- Oceanographic Center of Murcia, Instituto Español de Oceanografía (IEO), Murcia, Spain
| | - Yulema Valero
- Oceanographic Center of Murcia, Instituto Español de Oceanografía (IEO), Murcia, Spain.,Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, Murcia, Spain
| | - Maria Teresa Lozano
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, Murcia, Spain
| | - Pablo Rodríguez-Cerezo
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, Murcia, Spain
| | - Liang Miao
- School of Marine Science, Ningbo University, Ningbo, China
| | - Vittorio Campo
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Messina, Italy
| | - Maria Angeles Esteban
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, Murcia, Spain
| | - Alberto Cuesta
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, Murcia, Spain
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Leiva-Rebollo R, Labella AM, Borrego JJ, Castro D. Immune gene expression in gilthead seabream (Sparus aurata) after Lymphocystis disease virus (LCDV-Sa) challenge resulting in asymptomatic infection. J Appl Microbiol 2019; 128:41-53. [PMID: 31529740 DOI: 10.1111/jam.14454] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 08/04/2019] [Accepted: 09/04/2019] [Indexed: 12/27/2022]
Abstract
AIMS To determine the immune gene expression response of gilthead seabream (Sparus aurata) that is experimentally infected with the lymphocystivirus LCDV-Sa. METHODS AND RESULTS Viral DNA and transcripts were detected by qPCR in all samples from fish injected with LCDV-Sa, demonstrating that the virus establish a systemic and asymptomatic infection. The expression of 23 immune-related genes was also analysed by RT-qPCR in the head kidney (HK) and intestine at several times post-infection (dpi). In HK, the expression of five type I interferon (IFN)-related genes (ifn, irf3, mx2, mx3 and isg15), il10 and ck10 was upregulated at 1-3 dpi, while genes related to the inflammation process (tnfα, il1ß, il6, casp1) were not differentially expressed or even downregulated. The expression profile in the intestine was different regarding type I INF-related genes. An upregulated c3 and ighm expression was observed in both HK and intestine at 3-8 dpi. Finally, the transcription of nccrp1 and mhcIIα was induced in HK, whereas tcrβ expression was downregulated in both organs. CONCLUSIONS LCDV-Sa seems to trigger an immune response in gilthead seabream characterized by a partial activation of type I IFN system and a lack of systemic inflammatory response which may be related to viral persistence. SIGNIFICANCE AND IMPACT OF THE STUDY The immune response observed in gilthead seabream infected by LCDV-Sa could be implicated in the establishment of an asymptomatic persistent infection.
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Affiliation(s)
- R Leiva-Rebollo
- Departamento de Microbiología, Universidad de Málaga, Málaga, Spain
| | - A M Labella
- Departamento de Microbiología, Universidad de Málaga, Málaga, Spain
| | - J J Borrego
- Departamento de Microbiología, Universidad de Málaga, Málaga, Spain
| | - D Castro
- Departamento de Microbiología, Universidad de Málaga, Málaga, Spain
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Capsid amino acids at positions 247 and 270 are involved in the virulence of betanodaviruses to European sea bass. Sci Rep 2019; 9:14068. [PMID: 31575937 PMCID: PMC6773868 DOI: 10.1038/s41598-019-50622-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 08/16/2019] [Indexed: 12/28/2022] Open
Abstract
European sea bass (Dicentrarchus labrax) is severely affected by nervous necrosis disease, caused by nervous necrosis virus (NNV). Two out of the four genotypes of this virus (red-spotted grouper nervous necrosis virus, RGNNV; and striped jack nervous necrosis virus, SJNNV) have been detected in sea bass, although showing different levels of virulence to this fish species. Thus, sea bass is highly susceptible to RGNNV, whereas outbreaks caused by SJNNV have not been reported in this fish species. The role of the capsid protein (Cp) amino acids 247 and 270 in the virulence of a RGNNV isolate to sea bass has been evaluated by the generation of recombinant RGNNV viruses harbouring SJNNV-type amino acids in the above mentioned positions (Mut247Dl965, Mut270Dl965 and Mut247 + 270Dl965). Viral in vitro and in vivo replication, virus virulence and fish immune response triggered by these viruses have been analysed. Mutated viruses replicated on E-11 cells, although showing some differences compared to the wild type virus, suggesting that the mutations can affect the viral cell recognition and entry. In vivo, fish mortality caused by mutated viruses was 75% lower, and viral replication in sea bass brain was altered compared to non-mutated virus. Regarding sea bass immune response, mutated viruses triggered a lower induction of IFN I system and inflammatory response-related genes. Furthermore, mutations caused changes in viral serological properties (especially the mutation in amino acid 270), inducing higher seroconversion and changing antigen recognition.
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Buonocore F, Nuñez-Ortiz N, Picchietti S, Randelli E, Stocchi V, Guerra L, Toffan A, Pascoli F, Fausto AM, Mazzini M, Scapigliati G. Vaccination and immune responses of European sea bass (Dicentrarchus labrax L.) against betanodavirus. FISH & SHELLFISH IMMUNOLOGY 2019; 85:78-84. [PMID: 29175472 DOI: 10.1016/j.fsi.2017.11.039] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 10/18/2017] [Accepted: 11/22/2017] [Indexed: 05/22/2023]
Abstract
This review summarizes the available knowledge on the immune defences of European sea bass against antigenic preparations derived from the viral encephalopathy and retinopathy virus (betanodavirus), which represents a major threat to the health of this fish species. The nodavirus is widely present and differentiates into several strains that infect invertebrates (in insects, alphanodavirus) and teleost fish, and thus may represent a great problem for farmed fish species. Many efforts have been directed to discovering new immunizations to induce protection in sea bass, especially at young stages, and these efforts have included employing diverse betanodavirus strains, antigen preparation, vaccination routes, and the addition of adjuvants and/or immunostimulants. The obtained results showed that inactivated preparations of betanodavirus that were administered intraperitoneally may induce both immune recognition and protection. Attempts at performing mucosal immunization by immersion and/or oral administration, which is a vaccination route that is highly preferred for sea bass, have shown intriguing results, and more studies are necessary for its improvement. Overall, the objective of identifying a reliable vaccine that also cross-protects against different genotypes or reassortant viruses for use in European sea bass against betanodavirus appears to be an attainable goal in the near future.
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Affiliation(s)
- Francesco Buonocore
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, Viterbo, Italy.
| | - Noelia Nuñez-Ortiz
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, Viterbo, Italy
| | - Simona Picchietti
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, Viterbo, Italy
| | - Elisa Randelli
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, Viterbo, Italy
| | - Valentina Stocchi
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, Viterbo, Italy
| | - Laura Guerra
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, Viterbo, Italy
| | - Anna Toffan
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, Viterbo, Italy
| | - Francesco Pascoli
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, Viterbo, Italy
| | - Anna Maria Fausto
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, Viterbo, Italy
| | - Massimo Mazzini
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, Viterbo, Italy
| | - Giuseppe Scapigliati
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, Viterbo, Italy
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Valero Y, Mokrani D, Chaves-Pozo E, Arizcun M, Oumouna M, Meseguer J, Esteban MÁ, Cuesta A. Vaccination with UV-inactivated nodavirus partly protects European sea bass against infection, while inducing few changes in immunity. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2018; 86:171-179. [PMID: 29758230 DOI: 10.1016/j.dci.2018.05.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 05/10/2018] [Accepted: 05/10/2018] [Indexed: 05/19/2023]
Abstract
Developing viral vaccines through the ultraviolet (UV) inactivation of virus is promising technique since it is straightforward and economically affordable, while the resulting viruses are capable of eliciting an adequate antiviral immune response. Nodavirus (NNV) is a devastating virus that mainly affects European sea bass juveniles and larvae, causing serious economic losses in Mediterranean aquaculture. In this work, a potential vaccine consisting on UV-inactivated NNV (iNNV) was generated and administered to healthy juveniles of European sea bass to elucidate whether it triggers the immune response and improves their survival upon challenge. First, iNNV failed to replicate in cell cultures and its intraperitoneal administration to sea bass juveniles also failed to produce fish mortality and induction of the type I interferon (IFN) pathway, indicating that the NNV was efficiently inactivated. By contrast, iNNV administration induced significant serum non-specific antimicrobial activity as well as a specific antiviral activity and immunoglobulin M (IgM) titres against NNV. Interestingly, few changes were observed at transcriptional level in genes related to either innate or adaptive immunity, suggesting that iNNV could be modulating the immune response at protein or functional level. In addition, the iNNV vaccinated group showed improved survival, reaching a relative survival percentage of 57.9%. Moreover, challenged fish that had been vaccinated presented increased serum antibacterial, antiviral and IgM titres, as well as the higher transcription of mhc1a, ifn, isg15 and cd8a genes in brain, while in the head-kidney the transcription of mhc1a, mhc2b and cd8a was down-regulated and mx, isg15 and tcrb was up-regulated. Although the UV-inactivated vaccine against NNV showed promising results, more effort should be addressed to improving this prophylactic method by increasing our understanding of its action mechanisms, thus enabling the mortality rate of NNV to be further reduced.
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Affiliation(s)
- Yulema Valero
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n, Puerto de Mazarrón, 30860 Murcia, Spain; Grupo de Marcadores Inmunológicos, Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Djamal Mokrani
- Institut des Sciences Vétérinaires, Unniversité de Blida 1, Algeria
| | - Elena Chaves-Pozo
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n, Puerto de Mazarrón, 30860 Murcia, Spain
| | - Marta Arizcun
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n, Puerto de Mazarrón, 30860 Murcia, Spain
| | - Mustapha Oumouna
- Faculty of Natural Science and Life, University Dr. Yahia Fares, Medea, Algeria
| | - José Meseguer
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100 Murcia, Spain
| | - M Ángeles Esteban
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100 Murcia, Spain
| | - Alberto Cuesta
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100 Murcia, Spain.
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Labella AM, Garcia-Rosado E, Bandín I, Dopazo CP, Castro D, Alonso MC, Borrego JJ. Transcriptomic Profiles of Senegalese Sole Infected With Nervous Necrosis Virus Reassortants Presenting Different Degree of Virulence. Front Immunol 2018; 9:1626. [PMID: 30065724 PMCID: PMC6056728 DOI: 10.3389/fimmu.2018.01626] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 07/02/2018] [Indexed: 01/28/2023] Open
Abstract
Betanodaviruses [nervous necrosis virus (NNV)] are the causative agent of the viral encephalopathy and retinopathy, a disease that affects cultured Senegalese sole (Solea senegalensis). NNV reassortants, combining genomic segments from redspotted grouper nervous necrosis virus (RGNNV) and striped jack nervous necrosis virus (SJNNV) genotypes, have been previously isolated from several fish species. The wild-type reassortant wSs160.03, isolated from Senegalese sole, has been proven to be more virulent to sole than the parental genotypes (RGNNV and SJNNV), causing 100% mortality. Mutations at amino acids 247 (serine to alanine) and 270 (serine to asparagine) in the wSs160.03 capsid protein have allowed us to obtain a mutant reassortant (rSs160.03247+270), which provokes a 40% mortality decrease. In this study, the RNA-Seq technology has been used to comparatively analyze Senegalese sole transcriptomes in two organs (head kidney and eye/brain) after infection with wild-type and mutant strains. A total of 633 genes were differentially expressed (DEGs) in animals infected with the wild-type isolate (with higher virulence), whereas 393 genes were differentially expressed in animals infected with the mutant strain (37.9% decrease in the number of DEGs). To study the biological functions of detected DEGs involved in NNV infection, a gene ontology (GO) enrichment analysis was performed. Different GO profiles were obtained in the following subclasses: (i) biological process; (ii) cellular component; and (iii) molecular function, for each viral strain tested. Immune response and proteolysis have been the predominant biological process after the infection with the wild-type isolate, whereas the infection with the mutant strain induces proteolysis in head kidney and inhibition of vasculogenesis in nervous tissue. Regarding the immune response, genes coding for proteins acting as mediators of type I IFN expression (DHX58, IRF3, IRF7) and IFN-stimulated genes (ISG15, Mx, PKR, Gig1, ISG12, IFI44, IFIT-1, to name a few) were upregulated in animals infected with the wild-type isolate, whereas no-differential expression of these genes was observed in samples inoculated with the mutant strain. The different transcriptomic profiles obtained could help to better understand the NNV pathogenesis in Senegalese sole, setting up the importance as virulence determinants of amino acids at positions 247 and 270 within the RNA2 segment.
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Affiliation(s)
- Alejandro M Labella
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Malaga, Malaga, Spain
| | - Esther Garcia-Rosado
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Malaga, Malaga, Spain
| | - Isabel Bandín
- Departamento de Microbiología y Parasitología, Instituto de Acuicultura, Universidad de Santiago de Compostela, Santiago de Compostela, Spain
| | - Carlos P Dopazo
- Departamento de Microbiología y Parasitología, Instituto de Acuicultura, Universidad de Santiago de Compostela, Santiago de Compostela, Spain
| | - Dolores Castro
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Malaga, Malaga, Spain
| | - M Carmen Alonso
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Malaga, Malaga, Spain
| | - Juan J Borrego
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Malaga, Malaga, Spain
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Moreno P, Lopez-Jimena B, Randelli E, Scapigliati G, Buonocore F, Garcia-Rosado E, Borrego JJ, Alonso MC. Immuno-related gene transcription and antibody response in nodavirus (RGNNV and SJNNV)-infected European sea bass (Dicentrarchus labrax L.). FISH & SHELLFISH IMMUNOLOGY 2018; 78:270-278. [PMID: 29702239 DOI: 10.1016/j.fsi.2018.04.054] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 04/19/2018] [Accepted: 04/23/2018] [Indexed: 06/08/2023]
Abstract
The immune response of European sea bass to RGNNV and SJNNV infections has been evaluated by quantifying the transcription of some genes involved in the IFN I system, as well as in the inflammatory and adaptive immune mechanisms. The transcription of IFN-I, ISG-12, ISG-15 and MxA genes has been analyzed in brain and head kidney, showing that RGNNV genotype induces a more intense response of the IFN I system than SJNNV in both organs. In addition, the results obtained indicate the importance of the inflammatory response in nodavirus pathogenesis, with the transcription of IL-8 and TNF-α significantly higher in brain than in head kidney, being RGNNV the strongest inductor. An important difference between the immune response induced by both genotypes refers to the IgM titre in sera, which was higher in SJNNV-inoculated fish. The acquired response is also important locally, since TR-γ transcription is higher in brain than in head kidney (especially in the RGNNV-inoculated group). To our knowledge, this is the first study addressing the sea bass anti-SJNNV immune response.
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Affiliation(s)
- Patricia Moreno
- Universidad de Málaga, Departamento de Microbiología, Facultad de Ciencias, 29071 Málaga, Spain
| | - Benjamin Lopez-Jimena
- Mast Group Ltd., Mast House, Derby Road, Bootle, Merseyside, L20 1EA, England, United Kingdom
| | - Elisa Randelli
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, Viterbo, Italy
| | - Giuseppe Scapigliati
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, Viterbo, Italy
| | - Francesco Buonocore
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, Viterbo, Italy
| | - Esther Garcia-Rosado
- Universidad de Málaga, Departamento de Microbiología, Facultad de Ciencias, 29071 Málaga, Spain
| | - Juan J Borrego
- Universidad de Málaga, Departamento de Microbiología, Facultad de Ciencias, 29071 Málaga, Spain
| | - M Carmen Alonso
- Universidad de Málaga, Departamento de Microbiología, Facultad de Ciencias, 29071 Málaga, Spain.
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33
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Immune-Endocrine Interactions in the Fish Gonad during Infection: An Open Door to Vertical Transmission. FISHES 2018. [DOI: 10.3390/fishes3020024] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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34
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Valero Y, Boughlala B, Arizcun M, Patel S, Fiksdal IU, Esteban MÁ, De Juan J, Meseguer J, Chaves-Pozo E, Cuesta A. Genes related to cell-mediated cytotoxicity and interferon response are induced in the retina of European sea bass upon intravitreal infection with nodavirus. FISH & SHELLFISH IMMUNOLOGY 2018; 74:627-636. [PMID: 29414318 DOI: 10.1016/j.fsi.2018.01.034] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 01/18/2018] [Accepted: 01/21/2018] [Indexed: 06/08/2023]
Abstract
Viral diseases are responsible for high rates of mortality and subsequent economic losses in modern aquaculture. The nervous necrosis virus (NNV) produces viral encephalopathy and retinopathy (VER), which affects the central nervous system, is considered one of the most serious viral diseases in marine aquaculture. Although some studies have localized NNV in the retina cells, none has dealt with immunity in the retina. Thus, for the first time, we intravitreally infected healthy specimens of European sea bass (Dicentrarchus labrax) with NNV with the aim of characterizing the immune response in the retina. Ultrastructural analysis detected important retinal injuries and structure degradation, including pycnosis, hydropic degeneration and vacuolization in some cell layers as well as myelin sheaths in the optic nerve fibres. Immunohistochemistry demonstrated that NNV replicated in the eyes. Regarding retinal immunity, NNV infection elicited the transcription of genes encoding proteins involved in the interferon (IFN) and cell-mediated cytotoxicity (CMC) responses as well as B and T cell markers, demonstrating that viral replication influences innate and adaptive responses. Further studies are needed to understand the retina immunity and whether the main retinal function, vision, is affected by nodavirus.
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Affiliation(s)
- Yulema Valero
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n, Puerto de Mazarrón, 30860, Murcia, Spain; Grupo de Marcadores Inmunológicos, Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Bassima Boughlala
- Departamento de Biotecnología, Universidad de Alicante, Ctra. San Vicente-Alicante s/n, 03080, Alicante, Spain
| | - Marta Arizcun
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n, Puerto de Mazarrón, 30860, Murcia, Spain
| | - Sonal Patel
- Diseases and Pathogen Transmission, Institute of Marine Research, Nordnesgaten 50, 5005, Bergen, Norway
| | - Ingrid U Fiksdal
- Diseases and Pathogen Transmission, Institute of Marine Research, Nordnesgaten 50, 5005, Bergen, Norway
| | - M Ángeles Esteban
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain
| | - Joaquín De Juan
- Departamento de Biotecnología, Universidad de Alicante, Ctra. San Vicente-Alicante s/n, 03080, Alicante, Spain
| | - José Meseguer
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain
| | - Elena Chaves-Pozo
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n, Puerto de Mazarrón, 30860, Murcia, Spain
| | - Alberto Cuesta
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain.
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35
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Chaves-Pozo E, Valero Y, Esteve-Codina A, Gómez-Garrido J, Dabad M, Alioto T, Meseguer J, Esteban MÁ, Cuesta A. Innate Cell-Mediated Cytotoxic Activity of European Sea Bass Leucocytes Against Nodavirus-Infected Cells: A Functional and RNA-seq Study. Sci Rep 2017; 7:15396. [PMID: 29133947 PMCID: PMC5684396 DOI: 10.1038/s41598-017-15629-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 10/31/2017] [Indexed: 12/21/2022] Open
Abstract
Nervous necrosis virus (NNV) causes high mortalities in several marine species. We aimed to evaluate the innate cell-mediated cytotoxic (CMC) activity of head-kidney leucocytes (HKLs) isolated from naïve European sea bass (Dicentrarchus labrax) and gilthead seabream (Sparus aurata), a very susceptible and resistant fish species to NNV, respectively, against fish cell lines infected with NNV. Seabream HKLs showed significantly increased innate CMC activity against NNV-infected cells, compared to those uninfected, while sea bass HKLs failed to do so. Thus, we performed a RNA-seq study to identify genes related to the CMC activity of sea bass leucocytes. Thus, we found that sea bass HKLs incubated with DLB-1 cells alone (CMC_DLB1) or with NNV-infected DLB-1 cells (CMC_DLB1-NNV) showed very similar transcriptomic profiles and the GO analysis revealed that most of the up-regulated genes were related to immunity. Strikingly, when the CMC samples with and without NNV were compared, GO analysis revealed that most of the up-regulated genes in CMC_DLB1-NNV samples were related to metabolism and very few to immunity. This is also in agreement with the functional data. These data point to the escape of CMC activity by NNV infection as an important factor involved in the high susceptibility to nodavirus infections of European sea bass.
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Affiliation(s)
- Elena Chaves-Pozo
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n, Puerto de Mazarrón, 30860, Murcia, Spain
| | - Yulema Valero
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n, Puerto de Mazarrón, 30860, Murcia, Spain
- Grupo de Marcadores Inmunológicos, Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Anna Esteve-Codina
- CNAG-CRG, Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Baldiri i Reixac 4, 08028, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Jèssica Gómez-Garrido
- CNAG-CRG, Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Baldiri i Reixac 4, 08028, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Marc Dabad
- CNAG-CRG, Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Baldiri i Reixac 4, 08028, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Tyler Alioto
- CNAG-CRG, Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Baldiri i Reixac 4, 08028, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - José Meseguer
- CNAG-CRG, Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Baldiri i Reixac 4, 08028, Barcelona, Spain
| | - M Ángeles Esteban
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain
| | - Alberto Cuesta
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain.
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36
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Yong CY, Yeap SK, Omar AR, Tan WS. Advances in the study of nodavirus. PeerJ 2017; 5:e3841. [PMID: 28970971 PMCID: PMC5622607 DOI: 10.7717/peerj.3841] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 09/01/2017] [Indexed: 12/14/2022] Open
Abstract
Nodaviruses are small bipartite RNA viruses which belong to the family of Nodaviridae. They are categorized into alpha-nodavirus, which infects insects, and beta-nodavirus, which infects fishes. Another distinct group of nodavirus infects shrimps and prawns, which has been proposed to be categorized as gamma-nodavirus. Our current review focuses mainly on recent studies performed on nodaviruses. Nodavirus can be transmitted vertically and horizontally. Recent outbreaks have been reported in China, Indonesia, Singapore and India, affecting the aquaculture industry. It also decreased mullet stock in the Caspian Sea. Histopathology and transmission electron microscopy (TEM) are used to examine the presence of nodaviruses in infected fishes and prawns. For classification, virus isolation followed by nucleotide sequencing are required. In contrast to partial sequence identification, profiling the whole transcriptome using next generation sequencing (NGS) offers a more comprehensive comparison and characterization of the virus. For rapid diagnosis of nodavirus, assays targeting the viral RNA based on reverse-transcription PCR (RT-PCR) such as microfluidic chips, reverse-transcription loop-mediated isothermal amplification (RT-LAMP) and RT-LAMP coupled with lateral flow dipstick (RT-LAMP-LFD) have been developed. Besides viral RNA detections, diagnosis based on immunological assays such as enzyme-linked immunosorbent assay (ELISA), immunodot and Western blotting have also been reported. In addition, immune responses of fish and prawn are also discussed. Overall, in fish, innate immunity, cellular type I interferon immunity and humoral immunity cooperatively prevent nodavirus infections, whereas prawns and shrimps adopt different immune mechanisms against nodavirus infections, through upregulation of superoxide anion, prophenoloxidase, superoxide dismutase (SOD), crustin, peroxinectin, anti-lipopolysaccharides and heat shock proteins (HSP). Potential vaccines for fishes and prawns based on inactivated viruses, recombinant proteins or DNA, either delivered through injection, oral feeding or immersion, are also discussed in detail. Lastly, a comprehensive review on nodavirus virus-like particles (VLPs) is presented. In recent years, studies on prawn nodavirus are mainly focused on Macrobrachium rosenbergii nodavirus (MrNV). Recombinant MrNV VLPs have been produced in prokaryotic and eukaryotic expression systems. Their roles as a nucleic acid delivery vehicle, a platform for vaccine development, a molecular tool for mechanism study and in solving the structures of MrNV are intensively discussed.
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Affiliation(s)
- Chean Yeah Yong
- Institute of Bioscience, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | | | - Abdul Rahman Omar
- Institute of Bioscience, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Wen Siang Tan
- Institute of Bioscience, Universiti Putra Malaysia, Serdang, Selangor, Malaysia.,Department of Microbiology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
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Toffan A, Pascoli F, Pretto T, Panzarin V, Abbadi M, Buratin A, Quartesan R, Gijón D, Padrós F. Viral nervous necrosis in gilthead sea bream (Sparus aurata) caused by reassortant betanodavirus RGNNV/SJNNV: an emerging threat for Mediterranean aquaculture. Sci Rep 2017; 7:46755. [PMID: 28462930 PMCID: PMC5411978 DOI: 10.1038/srep46755] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 03/21/2017] [Indexed: 11/23/2022] Open
Abstract
Viral nervous necrosis (VNN) certainly represents the biggest challenge for the sustainability and the development of aquaculture. A large number of economically relevant fish species have proven to be susceptible to the disease. Conversely, gilthead sea bream has generally been considered resistant to VNN, although it has been possible to isolate the virus from apparently healthy sea bream and sporadically from affected larvae and postlarvae. Unexpectedly, in 2014–2016 an increasing number of hatcheries in Europe have experienced mass mortalities in sea bream larvae. Two clinical outbreaks were monitored over this time span and findings are reported in this paper. Despite showing no specific clinical signs, the affected fish displayed high mortality and histological lesions typical of VNN. Fish tested positive for betanodavirus by different laboratory techniques. The isolates were all genetically characterized as being reassortant strains RGNNV/SJNNV. A genetic characterization of all sea bream betanodaviruses which had been isolated in the past had revealed that the majority of the strains infecting sea bream are actually RGNNV/SJNNV. Taken together, this information strongly suggests that RGNNV/SJNNV betanodavirus possesses a particular tropism to sea bream, which can pose a new and unexpected threat to the Mediterranean aquaculture.
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Affiliation(s)
- Anna Toffan
- OIE reference centre for viral encephalopathy and retinopathy, Istituto Zooprofilattico Sperimentale delle Venezie, Viale dell'Università 10, Legnaro, Padova, Italy
| | - Francesco Pascoli
- OIE reference centre for viral encephalopathy and retinopathy, Istituto Zooprofilattico Sperimentale delle Venezie, Viale dell'Università 10, Legnaro, Padova, Italy
| | - Tobia Pretto
- Istituto Zooprofilattico Sperimentale delle Venezie, Fish Pathology Department, Via Leonardo da Vinci 39, Adria, Rovigo, Italy.,Department of Veterinary Medical Sciences, Alma Mater Studiorum University of Bologna, Via Tolara di Sopra 50, Ozzano dell'Emilia, Bologna, Italy
| | - Valentina Panzarin
- OIE reference centre for viral encephalopathy and retinopathy, Istituto Zooprofilattico Sperimentale delle Venezie, Viale dell'Università 10, Legnaro, Padova, Italy
| | - Miriam Abbadi
- OIE reference centre for viral encephalopathy and retinopathy, Istituto Zooprofilattico Sperimentale delle Venezie, Viale dell'Università 10, Legnaro, Padova, Italy
| | - Alessandra Buratin
- OIE reference centre for viral encephalopathy and retinopathy, Istituto Zooprofilattico Sperimentale delle Venezie, Viale dell'Università 10, Legnaro, Padova, Italy
| | - Rosita Quartesan
- OIE reference centre for viral encephalopathy and retinopathy, Istituto Zooprofilattico Sperimentale delle Venezie, Viale dell'Università 10, Legnaro, Padova, Italy
| | - Daniel Gijón
- Fish Health Service, Skretting, Ctra. de la Estación S/N, Cojóbar, Spain
| | - Francesc Padrós
- Fish Diseases Diagnostic Service, Facultat de Veterinaria, Universitat Autònoma de Barcelona, Bellaterra, Cerdanyola del Vallès, Spain
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38
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Cordero H, Cuesta A, Meseguer J, Esteban MA. Characterization of the gilthead seabream (Sparus aurata L.) immune response under a natural lymphocystis disease virus outbreak. JOURNAL OF FISH DISEASES 2016; 39:1467-1476. [PMID: 27133966 DOI: 10.1111/jfd.12481] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 02/25/2016] [Accepted: 02/26/2016] [Indexed: 06/05/2023]
Abstract
Lymphocystis or lymphocystis disease virus (LCDV) is distributed worldwide and affects many fresh and marine water fish species. LCDV is commonly found in aquaria fish species but also in farmed fish species, among them the gilthead seabream (Sparus aurata L.). The immune status of gilthead seabream (S. aurata) specimens under a natural outbreak of LCDV was studied. The replication of the virus was demonstrated in infected fish, but not in control fish. The results showed decreased total serum IgM levels and increased innate cellular immune response (peroxidase and respiratory burst activities) of head kidney leucocytes in LCDV-infected fish, compared to the values obtained in uninfected specimens. In addition, transcription of antiviral genes (ifn and irf3) was down-regulated in the skin of LCDV-positive fish as well as genes involved in cellular immunity (csf1r, mhc2a, tcra and ighm) that were down-regulated in skin and head kidney of infected fish. By contrast, the transcription of nccrp1 was up-regulated in head kidney after LCDV infection. These present results show that head kidney leucocytes are activated to encounter the virus at the sites of replication.
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Affiliation(s)
- H Cordero
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, Murcia, Spain
| | - A Cuesta
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, Murcia, Spain
| | - J Meseguer
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, Murcia, Spain
| | - M A Esteban
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, Murcia, Spain.
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39
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Valero Y, Awad E, Buonocore F, Arizcun M, Esteban MÁ, Meseguer J, Chaves-Pozo E, Cuesta A. An oral chitosan DNA vaccine against nodavirus improves transcription of cell-mediated cytotoxicity and interferon genes in the European sea bass juveniles gut and survival upon infection. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2016; 65:64-72. [PMID: 27370973 DOI: 10.1016/j.dci.2016.06.021] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 06/26/2016] [Accepted: 06/26/2016] [Indexed: 05/19/2023]
Abstract
Vaccines for fish need to be improved for the aquaculture sector, with DNA vaccines and the oral administration route providing the most promising improvements. In this study, we have created an oral chitosan-encapsulated DNA vaccine (CP-pNNV) for the nodavirus (NNV) in order to protect the very susceptible European sea bass (Dicentrarchus labrax). Our data show that the oral CP-pNNV vaccine failed to induce serum circulating or neutralizing specific antibodies (immunoglobulin M) or to up-regulate their gene expression in the posterior gut. However, the vaccine up-regulated the expression of genes related to the cell-mediated cytotoxicity (CMC; tcrb and cd8a) and the interferon pathway (IFN; ifn, mx and ifng). In addition, 3 months after vaccination, challenged fish showed a retarded onset of fish death and lower cumulative mortality with a relative survival of 45%. Thus, we created a chitosan-encapsulated DNA vaccine against NNV that is partly protective to European sea bass juveniles and up-regulates the transcription of genes related to CMC and IFN. However, further studies are needed to improve the anti-NNV vaccine and to understand its mechanisms.
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Affiliation(s)
- Yulema Valero
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n, Puerto de Mazarrón, Murcia, Spain
| | - Elham Awad
- Department of Hydrobiology, National Research Center, Giza, Egypt
| | - Francesco Buonocore
- Dipartimento per l'Innovazione nei Sistemi Biologici Agroalimentari e Forestali, Università della Tuscia, Italy
| | - Marta Arizcun
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n, Puerto de Mazarrón, Murcia, Spain
| | - M Ángeles Esteban
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, Murcia, Spain
| | - José Meseguer
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, Murcia, Spain
| | - Elena Chaves-Pozo
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n, Puerto de Mazarrón, Murcia, Spain
| | - Alberto Cuesta
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, Murcia, Spain.
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40
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Nuñez-Ortiz N, Stocchi V, Toffan A, Pascoli F, Sood N, Buonocore F, Picchietti S, Papeschi C, Taddei AR, Thompson KD, Scapigliati G. Quantitative immunoenzymatic detection of viral encephalopathy and retinopathy virus (betanodavirus) in sea bass Dicentrarchus labrax. JOURNAL OF FISH DISEASES 2016; 39:821-831. [PMID: 26610431 DOI: 10.1111/jfd.12415] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 07/30/2015] [Accepted: 07/31/2015] [Indexed: 06/05/2023]
Abstract
Viral encephalopathy and retinopathy disease caused by betanodavirus, genus of the family Nodaviridae, affects marine, wild and farmed species including sea bass, one of the most important farmed species in Europe. This work describes a reliable and sensitive indirect ELISA assay to detect betanodavirus in biological samples using a polyclonal antiserum (pAb 283) against the 283/I09 virus strain, the most common red-spotted grouper nervous necrosis virus (RGNNV) genotype in the Mediterranean area, and a capture-based ELISA using a monoclonal antibody (mAb 4C3) specific to a common epitope present on the capsid protein. Using adsorbed, purified VERv preparation, the detection limit of indirect ELISA was 2 μg mL(-1) (3 × 10(5) TCID50 per mL), whereas for capture-based ELISA, the sensitivity for the antigen in solution was 17 μg mL(-1) (35 × 10(5) TCID50 per mL). The capture-based ELISA was employed to detect VERv in brain homogenates of in vivo infected sea bass and resulted positive in 22 of 32 samples, some of these with a high viral load estimates (about 1.1 × 10(8) TCID50 per mL). The ELISA system we propose may be helpful in investigations where coupling of viral content in fish tissues with the presence of circulating VERv-specific IgM is required, or for use in samples where PCR is difficult to perform.
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Affiliation(s)
- N Nuñez-Ortiz
- Dipartimento per l'Innovazione nei Sistemi Biologici Agroalimentari e Forestali, Università della Tuscia, Viterbo, Italy
| | - V Stocchi
- Dipartimento per l'Innovazione nei Sistemi Biologici Agroalimentari e Forestali, Università della Tuscia, Viterbo, Italy
| | - A Toffan
- Fish Virology Department, Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy
| | - F Pascoli
- Fish Virology Department, Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy
| | - N Sood
- National Bureau of Fish Genetic Resources, Lucknow, UP, India
| | - F Buonocore
- Dipartimento per l'Innovazione nei Sistemi Biologici Agroalimentari e Forestali, Università della Tuscia, Viterbo, Italy
| | - S Picchietti
- Dipartimento per l'Innovazione nei Sistemi Biologici Agroalimentari e Forestali, Università della Tuscia, Viterbo, Italy
| | - C Papeschi
- Dipartimento per l'Innovazione nei Sistemi Biologici Agroalimentari e Forestali, Università della Tuscia, Viterbo, Italy
| | - A R Taddei
- Centro di Microscopia Elettronica, Università della Tuscia, Viterbo, Italy
| | - K D Thompson
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Near Edimburgh, Scotland, UK
| | - G Scapigliati
- Dipartimento per l'Innovazione nei Sistemi Biologici Agroalimentari e Forestali, Università della Tuscia, Viterbo, Italy
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41
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Costa JZ, Thompson KD. Understanding the interaction between Betanodavirus and its host for the development of prophylactic measures for viral encephalopathy and retinopathy. FISH & SHELLFISH IMMUNOLOGY 2016; 53:35-49. [PMID: 26997200 DOI: 10.1016/j.fsi.2016.03.033] [Citation(s) in RCA: 111] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 03/04/2016] [Accepted: 03/15/2016] [Indexed: 05/22/2023]
Abstract
Over the last three decades, the causative agent of viral encephalopathy and retinopathy (VER) disease has become a serious problem of marine finfish aquaculture, and more recently the disease has also been associated with farmed freshwater fish. The virus has been classified as a Betanodavirus within the family Nodaviridae, and the fact that Betanodaviruses are known to affect more than 120 different farmed and wild fish and invertebrate species, highlights the risk that Betanodaviruses pose to global aquaculture production. Betanodaviruses have been clustered into four genotypes, based on the RNA sequence of the T4 variable region of their capsid protein, and are named after the fish species from which they were first derived i.e. Striped Jack nervous necrosis virus (SJNNV), Tiger puffer nervous necrosis virus (TPNNV), Barfin flounder nervous necrosis virus (BFNNV) and Red-spotted grouper nervous necrosis virus (RGNNV), while an additional genotype turbot betanodavirus strain (TNV) has also been proposed. However, these genotypes tend to be associated with a particular water temperature range rather than being species-specific. Larvae and juvenile fish are especially susceptible to VER, with up to 100% mortality resulting in these age groups during disease episodes, with vertical transmission of the virus increasing the disease problem in smaller fish. A number of vaccine preparations have been tested in the laboratory and in the field e.g. inactivated virus, recombinant proteins, virus-like particles and DNA based vaccines, and their efficacy, based on relative percentage survival, has ranged from medium to high levels of protection to little or no protection. Ultimately a combination of effective prophylactic measures, including vaccination, is needed to control VER, and should also target larvae and broodstock stages of production to help the industry deal with the problem of vertical transmission. As yet there are no commercial vaccines for VER and the aquaculture industry eagerly awaits such a product. In this review we provide an overview on the current state of knowledge of the disease, the pathogen, and interactions between betanodavirus and its host, to provide a greater understanding of the multiple factors involved in the disease process. Such knowledge is needed to develop effective methods for controlling VER in the field, to protect the various aquaculture species farmed globally from the different Betanodavirus genotypes to which they are susceptible.
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Affiliation(s)
- Janina Z Costa
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Scotland, EH26 0PZ, United Kingdom.
| | - Kim D Thompson
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Scotland, EH26 0PZ, United Kingdom
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Carballo C, Garcia-Rosado E, Borrego JJ, Alonso MC. SJNNV down-regulates RGNNV replication in European sea bass by the induction of the type I interferon system. Vet Res 2016; 47:6. [PMID: 26743933 PMCID: PMC4705746 DOI: 10.1186/s13567-015-0304-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Accepted: 04/17/2015] [Indexed: 01/09/2023] Open
Abstract
European sea bass is highly susceptible to the betanodavirus RGNNV genotype, although the SJNNV genotype has also been detected in this fish species. The coexistence of both genotypes may affect the replication of both viruses by viral interaction or by stimulation of the host antiviral defense system in which the IFN I system plays a key role. IFN I triggers the transcription of interferon-stimulated genes, including Mx genes, whose expression has been used as a reporter of IFN I activity. The present study evaluated the effect of a primary exposure to an SJNNV isolate on a subsequent RGNNV infection and analyzed the role of the IFN I system in controlling VNNV infections in sea bass using different in vivo approaches. VNNV infection and Mx transcription were comparatively evaluated after single infections, superinfection (SJ+RG) and co-infection (poly I:C+RG). The single RGNNV infection resulted in a 24% survival rate, whereas the previous SJNNV or poly I:C inoculation increased the survival rate up to 96 and 100%, respectively. RGNNV replication in superinfection was reduced compared with RGNNV replication after a single inoculation. Mx transcription analysis shows differential induction of the IFN I system by both isolates. SJNNV was a potent Mx inducer, whereas RGNNV induced lower Mx transcription and did not interfere with the IFN I system triggered by SJNNV or poly I:C. This study demonstrates that an antiviral state exists after SJNNV and poly I:C injection, suggesting that the IFN I system plays an important role against VNNV infections in sea bass.
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Affiliation(s)
- Carlos Carballo
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, 29071, Málaga, Spain. .,IFAPA centro El Toruño, Junta de Andalucía, El Puerto de Santa María, Cádiz, Spain.
| | - Esther Garcia-Rosado
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, 29071, Málaga, Spain.
| | - Juan J Borrego
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, 29071, Málaga, Spain.
| | - M Carmen Alonso
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, 29071, Málaga, Spain.
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Valero Y, Arizcun M, Esteban MÁ, Bandín I, Olveira JG, Patel S, Cuesta A, Chaves-Pozo E. Nodavirus Colonizes and Replicates in the Testis of Gilthead Seabream and European Sea Bass Modulating Its Immune and Reproductive Functions. PLoS One 2015; 10:e0145131. [PMID: 26691348 PMCID: PMC4686992 DOI: 10.1371/journal.pone.0145131] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 11/26/2015] [Indexed: 12/20/2022] Open
Abstract
Viruses are threatening pathogens for fish aquaculture. Some of them are transmitted through gonad fluids or gametes as occurs with nervous necrosis virus (NNV). In order to be transmitted through the gonad, the virus should colonize and replicate inside some cell types of this tissue and avoid the subsequent immune response locally. However, whether NNV colonizes the gonad, the cell types that are infected, and how the immune response in the gonad is regulated has never been studied. We have demonstrated for the first time the presence and localization of NNV into the testis after an experimental infection in the European sea bass (Dicentrarchus labrax), and in the gilthead seabream (Sparus aurata), a very susceptible and an asymptomatic host fish species, respectively. Thus, we localized in the testis viral RNA in both species using in situ PCR and viral proteins in gilthead seabream by immunohistochemistry, suggesting that males might also transmit the virus. In addition, we were able to isolate infective particles from the testis of both species demonstrating that NNV colonizes and replicates into the testis of both species. Blood contamination of the tissues sampled was discarded by completely fish bleeding, furthermore the in situ PCR and immunocytochemistry techniques never showed staining in blood vessels or cells. Moreover, we also determined how the immune and reproductive functions are affected comparing the effects in the testis with those found in the brain, the main target tissue of the virus. Interestingly, NNV triggered the immune response in the European sea bass but not in the gilthead seabream testis. Regarding reproductive functions, NNV infection alters 17β-estradiol and 11-ketotestosterone production and the potential sensitivity of brain and testis to these hormones, whereas there is no disruption of testicular functions according to several reproductive parameters. Moreover, we have also studied the NNV infection of the testis in vitro to assess local responses. Our in vitro results show that the changes observed on the expression of immune and reproductive genes in the testis of both species are different to those observed upon in vivo infections in most of the cases.
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Affiliation(s)
- Yulema Valero
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n. Puerto de Mazarrón, Murcia, Spain
| | - Marta Arizcun
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n. Puerto de Mazarrón, Murcia, Spain
| | - M. Ángeles Esteban
- Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, Murcia, Spain
| | - Isabel Bandín
- Unidad de Ictiopatología-Patología Viral, Departamento de Microbiología y Parasitología, Instituto de Acuicultura, Universidad de Santiago de Compostela, Campus Vida, Santiago de Compostela, Spain
| | - José G. Olveira
- Unidad de Ictiopatología-Patología Viral, Departamento de Microbiología y Parasitología, Instituto de Acuicultura, Universidad de Santiago de Compostela, Campus Vida, Santiago de Compostela, Spain
| | - Sonal Patel
- Institute of Marine Research, Bergen, Norway
| | - Alberto Cuesta
- Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, Murcia, Spain
| | - Elena Chaves-Pozo
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n. Puerto de Mazarrón, Murcia, Spain
- * E-mail:
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44
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Fish Peroxiredoxins and Their Role in Immunity. BIOLOGY 2015; 4:860-80. [PMID: 26633533 PMCID: PMC4690020 DOI: 10.3390/biology4040860] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 11/04/2015] [Accepted: 11/19/2015] [Indexed: 01/05/2023]
Abstract
Peroxiredoxins (Prxs) are a family of antioxidant enzymes that protect cells from oxidative damage. In addition, Prxs may act as modulators of inflammation, protect against cell death and tumour progression, and facilitate tissue repair after damage. The most studied roles of Prx1 and Prx2 are immunological. Here we present a review on the effects of some immunostimulant treatments and bacterial, viral, or parasitic infections on the expression of fish Prxs at the gene and/or protein level, and point to their important role in immunity. The Prxs show antioxidant activity as well as a protective effect against infection. Some preliminary data are presented about the role of fish Prx1 and Prx2 in virus resistance although further studies are needed before the role of fish Prx in immunity can be definitively defined.
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45
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Havixbeck JJ, Rieger AM, Wong ME, Hodgkinson JW, Barreda DR. Neutrophil contributions to the induction and regulation of the acute inflammatory response in teleost fish. J Leukoc Biol 2015; 99:241-52. [PMID: 26292979 DOI: 10.1189/jlb.3hi0215-064r] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 07/14/2015] [Indexed: 12/31/2022] Open
Abstract
Neutrophils are essential to the acute inflammatory response, where they serve as the first line of defense against infiltrating pathogens. We report that, on receiving the necessary signals, teleost (Carassius auratus) neutrophils leave the hematopoietic kidney, enter into the circulation, and dominate the initial influx of cells into a site of inflammation. Unlike mammals, teleost neutrophils represent <5% of circulating leukocytes during periods of homeostasis. However, this increases to nearly 50% immediately after intraperitoneal challenge with zymosan, identifying a period of neutrophilia that precedes the peak influx of neutrophils into the challenge site at 18 h after injection). We demonstrate that neutrophils at the site of inflammation alter their phenotype throughout the acute inflammatory response, and contribute to both the induction and the resolution of inflammation. However, neutrophils isolated during the proinflammatory phase (18 h after injection) produced robust respiratory burst responses, released inflammation-associated leukotriene B(4), and induced macrophages to increase reactive oxygen species production. In contrast, neutrophils isolated at 48 h after infection (proresolving phase) displayed low levels of reactive oxygen species, released the proresolving lipid mediator lipoxin A(4), and downregulated reactive oxygen species production in macrophages before the initiation of apoptosis. Lipoxin A(4) was a significant contributor to the uptake of apoptotic cells by teleost macrophages and also played a role, at least in part, in the downregulation of macrophage reactive oxygen species production. Our results highlight the contributions of neutrophils to both the promotion and the regulation of teleost fish inflammation and provide added context for the evolution of this hematopoietic lineage.
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Affiliation(s)
- Jeffrey J Havixbeck
- Departments of *Biological Sciences and Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
| | - Aja M Rieger
- Departments of *Biological Sciences and Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
| | - Michael E Wong
- Departments of *Biological Sciences and Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
| | - Jordan W Hodgkinson
- Departments of *Biological Sciences and Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
| | - Daniel R Barreda
- Departments of *Biological Sciences and Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
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46
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Li MF, Li YX, Sun L. CD83 is required for the induction of protective immunity by a DNA vaccine in a teleost model. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2015; 51:141-7. [PMID: 25800093 DOI: 10.1016/j.dci.2015.03.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 03/08/2015] [Accepted: 03/09/2015] [Indexed: 06/04/2023]
Abstract
In mammals, CD83 is a surface marker on mature dendritic cells and vital to lymphocyte activation. In teleost, studies on the function of CD83 are very limited. In this study, we examined the potential involvement of turbot (Scophthalmus maximus) CD83, SmCD83, in vaccine-induced immunity. For this purpose, turbot were immunized with pORF75, a DNA vaccine against megalocytivirus, in the presence or absence of pSmCD83, a plasmid that constitutively expresses SmCD83. Immune response and protection analysis showed that the presence of pSmCD83 significantly (i) enhanced the activation of head kidney macrophages (HKM) and immune gene expression, (ii) inhibited viral replication in fish tissues following megalocytivirus challenge and increased the survival of the vaccinated fish, and (iii) stimulated production of specific serum antibody and the cytotoxicity of peripheral blood leukocytes. To further examine the effect of SmCD83, pORF75 was administered into turbot in which SmCD83 was knocked down. Subsequent analysis showed that in fish with SmCD83 knockdown, vaccine-induced HKM activation and antibody production were severely reduced, and, consistently, the protectivity of pORF75 was drastically decreased. Taken together, these results indicate for the first time that teleost CD83 is required for the induction of protective immune response by DNA vaccine.
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Affiliation(s)
- Mo-fei Li
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yong-xin Li
- Taishan Vocational College of Nursing, Tai'an 271000, China
| | - Li Sun
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Collaborative Innovation Center of Deep Sea Biology, Zhejiang University, Hangzhou, China.
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47
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Valero Y, García-Alcázar A, Esteban MÁ, Cuesta A, Chaves-Pozo E. Antimicrobial response is increased in the testis of European sea bass, but not in gilthead seabream, upon nodavirus infection. FISH & SHELLFISH IMMUNOLOGY 2015; 44:203-213. [PMID: 25707600 DOI: 10.1016/j.fsi.2015.02.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 01/14/2015] [Accepted: 02/10/2015] [Indexed: 06/04/2023]
Abstract
Antimicrobial peptides (AMPs) have a crucial role in the fish innate immune response, being considered a fundamental component of the first line of defence against pathogens. Moreover, AMPs have not been studied in the fish gonad since this is used by some pathogens as a vehicle or a reservoir to be transmitted to the progeny, as occurs with nodavirus (VNNV), which shows vertical transmission through the gonad and/or gonadal fluids, but no study has looked into the gonad of infected fish. In this framework, we have characterized the antimicrobial response triggered by VNNV in the testis of European sea bass, a very susceptible species of the virus, and in the gilthead seabream, which acts as a reservoir, both in vivo and in vitro, and compared with that present in the serum and brain (target tissue of VNNV). First, our data show a great antiviral response in the brain of gilthead seabream and in the gonad of European sea bass. In addition, for the first time, our results demonstrate that the antimicrobial activities (complement, lysozyme and bactericidal) and the expression of AMP genes such as complement factor 3 (c3), lysozyme (lyz), hepcidin (hamp), dicentracin (dic), piscidin (pis) or β-defensin (bdef) in the gonad of both species are very different, but generally activated in the European sea bass, probably related with the differences of susceptibility upon VNNV infection, and even differs to the brain response. Furthermore, the in vitro data suggest that some AMPs are locally regulated playing a local immune response in the gonad, while others are more dependent of the systemic immune system. Data are discussed in the light to ascertain their potential role in viral clearance by the gonad to avoid vertical transmission.
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Affiliation(s)
- Yulema Valero
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n. Puerto de Mazarrón, 30860 Murcia, Spain
| | - Alicia García-Alcázar
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n. Puerto de Mazarrón, 30860 Murcia, Spain
| | - M Ángeles Esteban
- Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100 Murcia, Spain
| | - Alberto Cuesta
- Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100 Murcia, Spain
| | - Elena Chaves-Pozo
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n. Puerto de Mazarrón, 30860 Murcia, Spain.
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48
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Valero Y, Morcillo P, Meseguer J, Buonocore F, Esteban MA, Chaves-Pozo E, Cuesta A. Characterization of the IFN pathway in the teleost fish gonad against vertically transmitted viral nervous necrosis virus. J Gen Virol 2015; 96:2176-2187. [PMID: 25918238 DOI: 10.1099/vir.0.000164] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
One of the most powerful innate immune responses against viruses is mediated by type I IFN. In teleost fish, it is known that virus infection triggers the expression of ifn and many IFN-stimulated genes, but the viral RNA sensors and mediators leading to IFN production are scarcely known. Thus, we have searched for the presence of these genes in gilt-head sea bream (Sparus aurata) and European sea bass (Dicentrarchus labrax), and evaluated their expression after infection with viral nervous necrosis virus (VNNV) in the brain, the main viral target tissue, and the gonad, used to transmit the virus vertically. In sea bream, a fish species resistant to the VNNV strain used, we found an upregulation of the genes encoding MDA5 (melanoma differentiation-associated gene 5), TBK1 (TANK-binding kinase 1), IRF3 (IFN regulatory factor 3), IFN, Mx [myxovirus (influenza) resistance protein] and PKR (dsRNA-dependent protein kinase receptor) proteins in the brain, which were unaltered in the gonad and could favour the dissemination by gonad fluids or gametes. Strikingly, in European sea bass, a very susceptible species, we also identified, transcripts coding for LGP2 (Laboratory of Genetics and Physiology 2), MAVS (mitochondrial antiviral signalling), TRAF3 (TNF receptor-associated factor 3), TANK (TRAF family member-associated NFκB activator) and IRF7 (IFN regulatory factor 7), and found that all the genes analysed were upregulated in the gonad, but only mda5, lgp2, irf3, mx and pkr were upregulated in the brain. These findings supported the notion that the European sea bass brain innate immune response is unable to clear the virus and pointed to the importance of gonad immunity to control the dissemination of VNNV to the progeny--an aspect that is worth investigating in aquatic animals.
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Affiliation(s)
- Yulema Valero
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n, Puerto de Mazarrón, 30860 Murcia, Spain
| | - Patricia Morcillo
- Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence 'Campus Mare Nostrum', University of Murcia, 30100 Murcia, Spain
| | - José Meseguer
- Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence 'Campus Mare Nostrum', University of Murcia, 30100 Murcia, Spain
| | - Francesco Buonocore
- Dipartimento per l'Innovazione nei Sistemi Biologici Agroalimentari e Forestali, Università della Tuscia, Italy
| | - María A Esteban
- Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence 'Campus Mare Nostrum', University of Murcia, 30100 Murcia, Spain
| | - Elena Chaves-Pozo
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n, Puerto de Mazarrón, 30860 Murcia, Spain
| | - Alberto Cuesta
- Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence 'Campus Mare Nostrum', University of Murcia, 30100 Murcia, Spain
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49
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Zhang J, Zhang BC, Sun L. P247 and p523: two in vivo-expressed megalocytivirus proteins that induce protective immunity and are essential to viral infection. PLoS One 2015; 10:e0121282. [PMID: 25815484 PMCID: PMC4376877 DOI: 10.1371/journal.pone.0121282] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Accepted: 01/29/2015] [Indexed: 12/31/2022] Open
Abstract
Megalocytivirus is a DNA virus with a broad host range among teleost fish. Although the complete genome sequences of a number of megalocytivirus isolates have been reported, the functions of most of the genes of this virus are unknown. In this study, we selected two megalocytivirus immunogens, P247 and P523, which were expressed during host infection and, when in the form of DNA vaccines (pCN247 and pCN523 respectively), elicited strong protectivity against lethal megalocytivirus challenge in a turbot (Scophthalmus maximus) model. Compared to control fish, fish vaccinated with pCN247 and pCN523 exhibited drastically reduced viral loads in tissues and high levels of survival rates. Immune response analysis showed that pCN247 and pCN523 (i) induced production of specific serum antibodies, (ii) caused generation of cytotoxic immune cells and specific memory immune cells that responded to secondary antigen stimulation, and (iii) upregulated the expression of genes involved in innate and adaptive immunity. To examine the potential role of P247 and P523 in viral infection, the expression of P247 and P523 was knocked down by siRNA. Subsequent in vivo infection study showed that P247 and P523 knockdown significantly impaired viral replication. Furthermore, whole-genome transcriptome analysis revealed that P247 and P523 knockdown altered the expression profiles of 26 and 41 viral genes, respectively, putatively participating in diverse aspects of viral infection. Taken together, these results indicate that P247 and P523 induce protective immunity in teleost and play fundamental roles essential to viral replication. These observations provide the first evidence that suggests a likely link between the protectivity of viral immunogens and their biological significance in viral replication.
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Affiliation(s)
- Jian Zhang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Bao cun Zhang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Li Sun
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
- * E-mail:
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50
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Chen YM, Wang TY, Chen TY. Immunity to betanodavirus infections of marine fish. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2014; 43:174-83. [PMID: 23916690 DOI: 10.1016/j.dci.2013.07.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2013] [Revised: 07/26/2013] [Accepted: 07/26/2013] [Indexed: 05/07/2023]
Abstract
Betanodaviruses cause viral nervous necrosis in numerous fish species, but some species are resistant to infection by these viruses. It is essential to fully characterize the immune responses that underlie this protective response. Complete characterization of the immune responses against nodaviruses may allow the development of methods that stimulate fish immunity and of an effective betanodavirus vaccine. Such strategies could include stimulation of specific immune system responses or blockage of factors that decrease the immune response. The innate immune system clearly provides a front-line defense, and this includes the production of interferons and other cytokines. Interferons that are released inside infected cells and that suppress viral replication may be the most ancient form of innate immunity. This review focuses on the immune responses of fish to betanodavirus infection.
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Affiliation(s)
- Young-Mao Chen
- Laboratory of Molecular Genetics, Institute of Biotechnology, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan 70101, Taiwan; Translational Center for Marine Biotechnology, National Cheng Kung University, Tainan 70101, Taiwan; Agriculture Biotechnology Research Center, National Cheng Kung University, Tainan 70101, Taiwan
| | - Ting-Yu Wang
- Laboratory of Molecular Genetics, Institute of Biotechnology, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan 70101, Taiwan; Translational Center for Marine Biotechnology, National Cheng Kung University, Tainan 70101, Taiwan
| | - Tzong-Yueh Chen
- Laboratory of Molecular Genetics, Institute of Biotechnology, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan 70101, Taiwan; Translational Center for Marine Biotechnology, National Cheng Kung University, Tainan 70101, Taiwan; Agriculture Biotechnology Research Center, National Cheng Kung University, Tainan 70101, Taiwan; University Center for Bioscience and Biotechnology, National Cheng Kung University, Tainan 70101, Taiwan; Research Center of Ocean Environment and Technology, National Cheng Kung University, Tainan 70101, Taiwan.
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