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Xue X, Eslamloo K, Caballero-Solares A, Katan T, Umasuthan N, Taylor RG, Fast MD, Andreassen R, Rise ML. Characterization of the impact of dietary immunostimulant CpG on the expression of mRNA biomarkers involved in the immune responses in Atlantic salmon (Salmo salar). FISH & SHELLFISH IMMUNOLOGY 2024; 153:109840. [PMID: 39153579 DOI: 10.1016/j.fsi.2024.109840] [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: 03/27/2024] [Revised: 07/23/2024] [Accepted: 08/14/2024] [Indexed: 08/19/2024]
Abstract
Infectious diseases have significantly impacted Atlantic salmon aquaculture worldwide. Modulating fish immunity with immunostimulant-containing functional feeds could be an effective strategy in mitigating disease problems. Previously, we characterized the impact of polyriboinosinic polyribocytidylic acid (pIC) and formalin-killed typical Aeromonas salmonicida bacterin on miRNA expression in Atlantic salmon fed a commercial diet with and without immunostimulant CpG. A set of miRNA biomarkers of Atlantic salmon head kidney responding to pIC and/or bacterin immune stimulations was identified (Xue et al., 2019) [1]. Herein, we report a complementary qPCR study that investigated the impact of the pIC, bacterin and dietary CpG on the expression of immune-relevant mRNAs (n = 31) using the same samples as in the previous study (Xue et al., 2019) [1]. Twenty-six of these genes were predicted target transcripts of the pIC- and/or bacterin-responsive miRNAs identified in the earlier study. The current data showed that pIC and/or bacterin stimulations significantly modulated the majority of the qPCR-analyzed genes involved in various immune pathways. Some genes responded to both stimulations (e.g. tnfa, il10rb, ifng, irf9, cxcr3, campb) while others appeared to be stimulation specific [e.g. irf3, irf7a, il1r1, mxa, mapk3 (pIC only); clra (bacterin only)]. A. salmonicida bacterin stimulation produced a strong inflammatory response (e.g. higher expression of il1b, il8a and tnfa), while salmon stimulated with pIC showed robust interferon responses (both type I and II). Furthermore, the current data indicated significant down-regulation of immune-relevant transcripts (e.g. tlr9, irf5, il1r1, hsp90ab1, itgb2) by dietary immunostimulant CpG, especially among pre-injection and PBS-injected fish. Together with our prior miRNA study, the present research provided complementary information on Atlantic salmon anti-viral and anti-bacterial immune responses and on how dietary CpG may modulate these responses.
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Affiliation(s)
- Xi Xue
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada.
| | - Khalil Eslamloo
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada
| | - Albert Caballero-Solares
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada
| | - Tomer Katan
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada
| | - Navaneethaiyer Umasuthan
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada
| | - Richard G Taylor
- Cargill Animal Nutrition, 10383 165th Avenue NW, Elk River, MN, 55330, USA
| | - Mark D Fast
- Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, C1A 4P3, Canada
| | - Rune Andreassen
- Department of Life Sciences and Health, Faculty of Health Sciences, OsloMet-Oslo Metropolitan University, N-0130, Oslo, Norway
| | - Matthew L Rise
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada.
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Emam M, Kumar S, Eslamloo K, Caballero-Solares A, Hall JR, Xue X, Paradis H, Gendron RL, Santander J, Rise ML. Transcriptomic response of lumpfish ( Cyclopterus lumpus) head kidney to viral mimic, with a focus on the interferon regulatory factor family. Front Immunol 2024; 15:1439465. [PMID: 39211041 PMCID: PMC11357929 DOI: 10.3389/fimmu.2024.1439465] [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: 05/28/2024] [Accepted: 07/08/2024] [Indexed: 09/04/2024] Open
Abstract
The economic importance of lumpfish (Cyclopterus lumpus) is increasing, but several aspects of its immune responses are not well understood. To discover genes and mechanisms involved in the lumpfish antiviral response, fish were intraperitoneally injected with either the viral mimic polyinosinic:polycytidylic acid [poly(I:C)] or phosphate-buffered saline (PBS; vehicle control), and head kidneys were sampled 24 hours post-injection (hpi) for transcriptomic analyses. RNA sequencing (RNA-Seq) (adjusted p-value <0.05) identified 4,499 upregulated and 3,952 downregulated transcripts in the poly(I:C)-injected fish compared to the PBS-injected fish. Eighteen genes identified as differentially expressed by RNA-Seq were included in a qPCR study that confirmed the upregulation of genes encoding proteins with antiviral immune response functions (e.g., rsad2) and the downregulation of genes (e.g., jarid2b) with potential cellular process functions. In addition, transcript expression levels of 12 members of the interferon regulatory factor (IRF) family [seven of which were identified as poly(I:C)-responsive in this RNA-Seq study] were analyzed using qPCR. Levels of irf1a, irf1b, irf2, irf3, irf4b, irf7, irf8, irf9, and irf10 were significantly higher and levels of irf4a and irf5 were significantly lower in the poly(I:C)-injected fish compared to the PBS-injected fish. This research and associated new genomic resources enhance our understanding of the genes and molecular mechanisms underlying the lumpfish response to viral mimic stimulation and help identify possible therapeutic targets and biomarkers for viral infections in this species.
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Affiliation(s)
- Mohamed Emam
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - Surendra Kumar
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - Khalil Eslamloo
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John’s, NL, Canada
- Centre for Marine Applied Research, Dartmouth, NS, Canada
| | | | - Jennifer R. Hall
- Aquatic Research Cluster, Core Research Equipment and Instrument Training (CREAIT) Network, Ocean Sciences Centre, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - Xi Xue
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - Hélène Paradis
- Faculty of Medicine, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - Robert L. Gendron
- Faculty of Medicine, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - Javier Santander
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - Matthew L. Rise
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John’s, NL, Canada
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Rojas I, Caballero-Solares A, Vadboncoeur É, Sandrelli RM, Hall JR, Clow KA, Parrish CC, Rise ML, Swanson AK, Gamperl AK. Prolonged Cold Exposure Negatively Impacts Atlantic Salmon ( Salmo salar) Liver Metabolism and Function. BIOLOGY 2024; 13:494. [PMID: 39056688 PMCID: PMC11273521 DOI: 10.3390/biology13070494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2024] [Revised: 06/12/2024] [Accepted: 06/28/2024] [Indexed: 07/28/2024]
Abstract
Large-scale mortality events have occurred during the winter in Atlantic salmon sea cages in Eastern Canada and Iceland. Thus, in salmon held at 3 °C that were apparently healthy (i.e., asymptomatic) and that had 'early' and 'advanced' symptoms of 'winter syndrome'/'winter disease' (WS/WD), we measured hepatic lipid classes and fatty acid levels, and the transcript expression of 34 molecular markers of fatty liver disease (FLD; a clinical sign of WS/WD). In addition, we correlated our results with previously reported characteristics associated with this disease's progression in these same individuals. Total lipid and triacylglycerol (TAG) levels increased by ~50%, and the expression of 32 of the 34 genes was dysregulated, in fish with symptoms of FLD. TAG was positively correlated with markers of inflammation (5loxa, saa5), hepatosomatic index (HSI), and plasma aspartate aminotransferase levels, but negatively correlated with genes related to lipid metabolism (elovl5b, fabp3a, cd36c), oxidative stress (catc), and growth (igf1). Multivariate analyses clearly showed that the three groups of fish were different, and that saa5 was the largest contributor to differences. Our results provide a number of biomarkers for FLD in salmon, and very strong evidence that prolonged cold exposure can trigger FLD in this ecologically and economically important species.
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Affiliation(s)
- Isis Rojas
- Department of Ocean Sciences, Memorial University of Newfoundland and Labrador, St. John’s, NL A1C 5S7, Canada (A.K.G.)
| | - Albert Caballero-Solares
- Department of Ocean Sciences, Memorial University of Newfoundland and Labrador, St. John’s, NL A1C 5S7, Canada (A.K.G.)
| | - Émile Vadboncoeur
- Department of Ocean Sciences, Memorial University of Newfoundland and Labrador, St. John’s, NL A1C 5S7, Canada (A.K.G.)
| | - Rebeccah M. Sandrelli
- Department of Ocean Sciences, Memorial University of Newfoundland and Labrador, St. John’s, NL A1C 5S7, Canada (A.K.G.)
| | - Jennifer R. Hall
- Aquatic Research Cluster, CREAIT Network, Ocean Sciences Centre, Memorial University of Newfoundland and Labrador, St. John’s, NL A1C 5S7, Canada
| | - Kathy A. Clow
- Department of Ocean Sciences, Memorial University of Newfoundland and Labrador, St. John’s, NL A1C 5S7, Canada (A.K.G.)
| | - Christopher C. Parrish
- Department of Ocean Sciences, Memorial University of Newfoundland and Labrador, St. John’s, NL A1C 5S7, Canada (A.K.G.)
| | - Matthew L. Rise
- Department of Ocean Sciences, Memorial University of Newfoundland and Labrador, St. John’s, NL A1C 5S7, Canada (A.K.G.)
| | | | - Anthony K. Gamperl
- Department of Ocean Sciences, Memorial University of Newfoundland and Labrador, St. John’s, NL A1C 5S7, Canada (A.K.G.)
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Gnanagobal H, Chakraborty S, Vasquez I, Chukwu-Osazuwa J, Cao T, Hossain A, Dang M, Valderrama K, Kumar S, Bindea G, Hill S, Boyce D, Hall JR, Santander J. Transcriptome profiling of lumpfish (Cyclopterus lumpus) head kidney to Renibacterium salmoninarum at early and chronic infection stages. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2024; 156:105165. [PMID: 38499166 DOI: 10.1016/j.dci.2024.105165] [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: 09/28/2023] [Revised: 03/08/2024] [Accepted: 03/15/2024] [Indexed: 03/20/2024]
Abstract
Renibacterium salmoninarum causes Bacterial Kidney Disease (BKD) in several fish species. Atlantic lumpfish, a cleaner fish, is susceptible to R. salmoninarum. To profile the transcriptome response of lumpfish to R. salmoninarum at early and chronic infection stages, fish were intraperitoneally injected with either a high dose of R. salmoninarum (1 × 109 cells dose-1) or PBS (control). Head kidney tissue samples were collected at 28- and 98-days post-infection (dpi) for RNA sequencing. Transcriptomic profiling identified 1971 and 139 differentially expressed genes (DEGs) in infected compared with control samples at 28 and 98 dpi, respectively. At 28 dpi, R. salmoninarum-induced genes (n = 434) mainly involved in innate and adaptive immune response-related pathways, whereas R. salmoninarum-suppressed genes (n = 1537) were largely connected to amino acid metabolism and cellular processes. Cell-mediated immunity-related genes showed dysregulation at 98 dpi. Several immune-signalling pathways were dysregulated in response to R. salmoninarum, including apoptosis, alternative complement, JAK-STAT signalling, and MHC-I dependent pathways. In summary, R. salmoninarum causes immune suppression at early infection, whereas lumpfish induce a cell-mediated immune response at chronic infection. This study provides a complete depiction of diverse immune mechanisms dysregulated by R. salmoninarum in lumpfish and opens new avenues to develop immune prophylactic tools to prevent BKD.
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Affiliation(s)
- Hajarooba Gnanagobal
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada.
| | - Setu Chakraborty
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Ignacio Vasquez
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Joy Chukwu-Osazuwa
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Trung Cao
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Ahmed Hossain
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
| | - My Dang
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Katherine Valderrama
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Surendra Kumar
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada; Ocean Frontier Institute, Ocean Sciences Centre, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Gabriela Bindea
- INSERM, Laboratory of Integrative Cancer Immunology, 75006, Paris, France; Equipe Labellisée Ligue Contre Le Cancer, 75013, Paris, France; Centre de Recherche des Cordeliers, Sorbonne Université, Université de Paris, 75006, Paris, France
| | - Stephen Hill
- Cold-Ocean Deep-Sea Research Facility, Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada
| | - Danny Boyce
- The Dr. Joe Brown Aquatic Research Building (JBARB), Ocean Sciences Centre, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Jennifer R Hall
- Aquatic Research Cluster, CREAIT Network, Ocean Sciences Centre, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Javier Santander
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada.
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Tsoulia T, Sundaram AYM, Braaen S, Jørgensen JB, Rimstad E, Wessel Ø, Dahle MK. Transcriptomics of early responses to purified Piscine orthoreovirus-1 in Atlantic salmon ( Salmo salar L.) red blood cells compared to non-susceptible cell lines. Front Immunol 2024; 15:1359552. [PMID: 38420125 PMCID: PMC10899339 DOI: 10.3389/fimmu.2024.1359552] [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: 12/21/2023] [Accepted: 01/23/2024] [Indexed: 03/02/2024] Open
Abstract
Piscine red blood cells (RBC) are nucleated and have been characterized as mediators of immune responses in addition to their role in gas exchange. Salmonid RBC are major target cells of Piscine orthoreovirus-1 (PRV-1), the etiological agent of heart and skeletal muscle inflammation (HSMI) in farmed Atlantic salmon (Salmo salar). PRV-1 replicates in RBC ex vivo, but no viral amplification has been possible in available A. salmon cell lines. To compare RBC basal transcripts and transcriptional responses to PRV-1 in the early phase of infection with non-susceptible cells, we exposed A. salmon RBC, Atlantic salmon kidney cells (ASK) and Salmon head kidney cells (SHK-1) to PRV-1 for 24 h. The RNA-seq analysis of RBC supported their previous characterization as pluripotent cells, as they expressed a wide repertoire of genes encoding pattern recognition receptors (PRRs), cytokine receptors, and genes implicated in antiviral activities. The comparison of RBC to ASK and SHK-1 revealed immune cell features exclusively expressed in RBC, such as genes involved in chemotactic activity in response to inflammation. Differential expression analysis of RBC exposed to PRV-1 showed 46 significantly induced genes (≥ 2-fold upregulation) linked to the antiviral response pathway, including RNA-specific PRRs and interferon (IFN) response factors. In SHK-1, PRV induced a more potent or faster antiviral response (213 genes induced). ASK cells showed a differential response pattern (12 genes induced, 18 suppressed) less characterized by the dsRNA-induced antiviral pathway. Despite these differences, the RIG-I-like receptor 3 (RLR3) in the family of cytosolic dsRNA receptors was significantly induced in all PRV-1 exposed cells. IFN regulatory factor 1 (IRF1) was significantly induced in RBC only, in contrast to IRF3/IRF7 induced in SHK-1. Differences in IRF expression and activity may potentially affect viral propagation.
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Affiliation(s)
- Thomais Tsoulia
- Departments of Aquatic Animal Health and Analysis and Diagnostics, Norwegian Veterinary Institute, Ås, Norway
- Department of Biotechnology, Fisheries and Economy, UiT Arctic University of Norway, Tromsø, Norway
| | - Arvind Y. M. Sundaram
- Departments of Aquatic Animal Health and Analysis and Diagnostics, Norwegian Veterinary Institute, Ås, Norway
- Department of Medical Genetics, Oslo University Hospital, Oslo, Norway
| | - Stine Braaen
- Department of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Jorunn B. Jørgensen
- Department of Biotechnology, Fisheries and Economy, UiT Arctic University of Norway, Tromsø, Norway
| | - Espen Rimstad
- Department of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Øystein Wessel
- Department of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Maria K. Dahle
- Departments of Aquatic Animal Health and Analysis and Diagnostics, Norwegian Veterinary Institute, Ås, Norway
- Department of Biotechnology, Fisheries and Economy, UiT Arctic University of Norway, Tromsø, Norway
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Ignatz EH, Rise ML, Gamperl AK. Impact of stress phenotype, elevated temperature, and bacterin exposure on male Atlantic salmon ( Salmo salar) growth, stress, and immune biomarker gene expression. Physiol Genomics 2023; 55:587-605. [PMID: 37746713 DOI: 10.1152/physiolgenomics.00055.2023] [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: 06/16/2023] [Revised: 08/30/2023] [Accepted: 09/21/2023] [Indexed: 09/26/2023] Open
Abstract
In this study, postsmolt male Atlantic salmon, previously identified as low responders (LRs) or high responders (HRs) based on poststress cortisol levels, had their head kidney and liver sampled at 12°C and 20°C before injection (time 0) and after injection (i.e., at 12- and 24-h postinjection, respectively) with either Forte Micro (a multivalent vaccine containing bacterin, to capture peak antibacterial responses) or an equal volume of PBS. Quantitative real-time PCR (qPCR) was then used to measure the expression of 15 biomarker genes in the head kidney and 12 genes in the liver at each temperature/sampling point. Target transcripts were chosen that were related to growth, stress, and innate antibacterial immune responses. Many temperature, phenotype, and injection effects were found for individual genes within these three broad categories, and multivariate statistical analyses (i.e., principal component analysis and permutational multivariate analysis of variance) were used to look for overall patterns in transcript expression. These analyses revealed that HR salmon at 20°C mounted a more robust response (P < 0.05) for the 10 head kidney immune-related transcripts when injected with Forte Micro than LR salmon. In contrast, the seven liver stress-related transcripts displayed a greater response (P = 0.057) in LR versus HR fish with Forte Micro at 12°C. Overall, although this research did find some differences between LR and HR fish, it does not provide strong (conclusive) evidence that the selection of a particular phenotype would have major implications for the health of salmon over the temperature range examined.NEW & NOTEWORTHY This is the first paper to describe the impact of both temperature and bacterial stimulation on head kidney and liver transcript expression in Atlantic salmon characterized as LRs versus HRs. Notably, we found that HR salmon at 20°C mounted a more robust innate antibacterial immune response than LR salmon. In addition, LR fish at 12°C may (P = 0.057) exhibit higher expression of stress-related transcripts in response to vaccine injection relative to HR fish.
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Affiliation(s)
- Eric H Ignatz
- Department of Ocean Sciences, Memorial University, St. John's, Newfoundland and Labrador, Canada
| | - Matthew L Rise
- Department of Ocean Sciences, Memorial University, St. John's, Newfoundland and Labrador, Canada
| | - A Kurt Gamperl
- Department of Ocean Sciences, Memorial University, St. John's, Newfoundland and Labrador, Canada
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Mora-Salas P, Zapararte S, Villouta P, Araya-León H, Avendaño-Herrera R, Melo F, Mardones FO. Method for lineage typing of epidemic Renibacterium salmoninarum in Chilean salmon farms. JOURNAL OF FISH DISEASES 2023; 46:499-506. [PMID: 36696457 DOI: 10.1111/jfd.13761] [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: 11/21/2022] [Revised: 01/09/2023] [Accepted: 01/11/2023] [Indexed: 06/17/2023]
Abstract
Renibacterium salmoninarum (Rs) is the etiological agent of bacterial kidney disease (BKD), which significantly affects farmed and wild salmonids worldwide. Although the whole genome of Rs (~3.1 million nucleotides) is highly conserved, genomic epidemiology analyses have identified four sub-lineages from Chilean isolates. A total of 94 Rs genomes from the BIGSdb aquaculture database were aligned and compared using bioinformatics tools, identifying 2199 independent single-nucleotide polymorphisms (SNPs) spread along the genome. A detailed analysis of the distribution of the SNPs showed five local zones of a length in the range of 10-15 kbp that should be used to unambiguously identify a specific sub-lineage. Based on the Rs type strain DSM 20767T , we designed multiplex PCR primers that produce specific amplification products which were further sequenced by the Sanger method to obtain the genotype of the sub-lineage. For the genetic typing, we evaluated 27 Rs isolates recovered from BKD outbreaks from different fish species and regions of Chile. Based on the findings reported here, we propose the PCR approach as a valuable tool for the rapid and reliable studying of the relationships between Rs isolates and the different sub-lineages without requiring the sequencing of the entire genome.
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Affiliation(s)
- Patricia Mora-Salas
- Escuela de Medicina Veterinaria, Facultad de Agronomía e Ingeniería Forestal, Facultad de Ciencias Biológicas y Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Sebastián Zapararte
- Laboratorio de Bioinformática Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Pamela Villouta
- Laboratorio de Bioinformática Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Henry Araya-León
- Laboratorio de Patología de Organismos Acuáticos y Biotecnología Acuícola, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Viña del Mar, Chile
- Centro FONDAP, Interdisciplinary Center for Aquaculture Research (INCAR), Universidad Andrés Bello, Viña del Mar, Chile
| | - Ruben Avendaño-Herrera
- Laboratorio de Patología de Organismos Acuáticos y Biotecnología Acuícola, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Viña del Mar, Chile
- Centro FONDAP, Interdisciplinary Center for Aquaculture Research (INCAR), Universidad Andrés Bello, Viña del Mar, Chile
- Centro de Investigaciones Marina Quintay (CIMARQ), Universidad Andrés Bello, Quintay, Chile
| | - Francisco Melo
- Laboratorio de Bioinformática Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
- Instituto de Ingeniería Biológica y Médica, Facultades de Ingeniería, Medicina y Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Fernando O Mardones
- Escuela de Medicina Veterinaria, Facultad de Agronomía e Ingeniería Forestal, Facultad de Ciencias Biológicas y Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
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Emam M, Eslamloo K, Caballero-Solares A, Lorenz EK, Xue X, Umasuthan N, Gnanagobal H, Santander J, Taylor RG, Balder R, Parrish CC, Rise ML. Nutritional immunomodulation of Atlantic salmon response to Renibacterium salmoninarum bacterin. Front Mol Biosci 2022; 9:931548. [PMID: 36213116 PMCID: PMC9532746 DOI: 10.3389/fmolb.2022.931548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 08/12/2022] [Indexed: 11/18/2022] Open
Abstract
We investigated the immunomodulatory effect of varying levels of dietary ω6/ω3 fatty acids (FA) on Atlantic salmon (Salmo salar) antibacterial response. Two groups were fed either high-18:3ω3 or high-18:2ω6 FA diets for 8 weeks, and a third group was fed for 4 weeks on the high-18:2ω6 diet followed by 4 weeks on the high-18:3ω3 diet and termed "switched-diet". Following the second 4 weeks of feeding (i.e., at 8 weeks), head kidney tissues from all groups were sampled for FA analysis. Fish were then intraperitoneally injected with either a formalin-killed Renibacterium salmoninarum bacterin (5 × 107 cells mL-1) or phosphate-buffered saline (PBS control), and head kidney tissues for gene expression analysis were sampled at 24 h post-injection. FA analysis showed that the head kidney profile reflected the dietary FA, especially for C18 FAs. The qPCR analyses of twenty-three genes showed that both the high-ω6 and high-ω3 groups had significant bacterin-dependent induction of some transcripts involved in lipid metabolism (ch25ha and lipe), pathogen recognition (clec12b and tlr5), and immune effectors (znrf1 and cish). In contrast, these transcripts did not significantly respond to the bacterin in the "switched-diet" group. Concurrently, biomarkers encoding proteins with putative roles in biotic inflammatory response (tnfrsf6b) and dendritic cell maturation (ccl13) were upregulated, and a chemokine receptor (cxcr1) was downregulated with the bacterin injection regardless of the experimental diets. On the other hand, an inflammatory regulator biomarker, bcl3, was only significantly upregulated in the high-ω3 fed group, and a C-type lectin family member (clec3a) was only significantly downregulated in the switched-diet group with the bacterin injection (compared with diet-matched PBS-injected controls). Transcript fold-change (FC: bacterin/PBS) showed that tlr5 was significantly over 2-fold higher in the high-18:2ω6 diet group compared with other diet groups. FC and FA associations highlighted the role of DGLA (20:3ω6; anti-inflammatory) and/or EPA (20:5ω3; anti-inflammatory) vs. ARA (20:4ω6; pro-inflammatory) as representative of the anti-inflammatory/pro-inflammatory balance between eicosanoid precursors. Also, the correlations revealed associations of FA proportions (% total FA) and FA ratios with several eicosanoid and immune receptor biomarkers (e.g., DGLA/ARA significant positive correlation with pgds, 5loxa, 5loxb, tlr5, and cxcr1). In summary, dietary FA profiles and/or regimens modulated the expression of some immune-relevant genes in Atlantic salmon injected with R. salmoninarum bacterin. The modulation of Atlantic salmon responses to bacterial pathogens and their associated antigens using high-ω6/high-ω3 diets warrants further investigation.
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Affiliation(s)
- Mohamed Emam
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - Khalil Eslamloo
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John’s, NL, Canada
| | | | - Evandro Kleber Lorenz
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - Xi Xue
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John’s, NL, Canada
| | | | - Hajarooba Gnanagobal
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - Javier Santander
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, St. John’s, NL, Canada
| | | | - Rachel Balder
- Cargill Animal Nutrition and Health, Minneapolis, MN, United States
| | - Christopher C. Parrish
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - Matthew L. Rise
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John’s, NL, Canada
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Host–Pathogen Interactions of Marine Gram-Positive Bacteria. BIOLOGY 2022; 11:biology11091316. [PMID: 36138795 PMCID: PMC9495620 DOI: 10.3390/biology11091316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 08/30/2022] [Accepted: 09/01/2022] [Indexed: 11/17/2022]
Abstract
Simple Summary Complex interactions between marine Gram-positive pathogens and fish hosts in the marine environment can result in diseases of economically important finfish, which cause economic losses in the aquaculture industry. Understanding how these pathogens interact with the fish host and generate disease will contribute to efficient prophylactic measures and treatments. To our knowledge, there are no systematic reviews on marine Gram-positive pathogens. Therefore, here we reviewed the host–pathogen interactions of marine Gram-positive pathogens from the pathogen-centric and host-centric points of view. Abstract Marine Gram-positive bacterial pathogens, including Renibacterium salmoninarum, Mycobacterium marinum, Nocardia seriolae, Lactococcus garvieae, and Streptococcus spp. cause economic losses in marine fish aquaculture worldwide. Comprehensive information on these pathogens and their dynamic interactions with their respective fish–host systems are critical to developing effective prophylactic measures and treatments. While much is known about bacterial virulence and fish immune response, it is necessary to synthesize the knowledge in terms of host–pathogen interactions as a centerpiece to establish a crucial connection between the intricate details of marine Gram-positive pathogens and their fish hosts. Therefore, this review provides a holistic view and discusses the different stages of the host–pathogen interactions of marine Gram-positive pathogens. Gram-positive pathogens can invade fish tissues, evade the fish defenses, proliferate in the host system, and modulate the fish immune response. Marine Gram-positive pathogens have a unique set of virulence factors that facilitate adhesion (e.g., adhesins, hemagglutination activity, sortase, and capsules), invasion (e.g., toxins, hemolysins/cytolysins, the type VII secretion system, and immune-suppressive proteins), evasion (e.g., free radical quenching, actin-based motility, and the inhibition of phagolysosomal fusion), and proliferation and survival (e.g., heme utilization and siderophore-mediated iron acquisition systems) in the fish host. After infection, the fish host initiates specific innate and adaptive immune responses according to the extracellular or intracellular mechanism of infection. Although efforts have continued to be made in understanding the complex interplay at the host–pathogen interface, integrated omics-based investigations targeting host–pathogen–marine environment interactions hold promise for future research.
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Saldarriaga-Córdoba M, Avendaño-Herrera R. Comparative pan-genomic analysis of 51 Renibacterium salmoninarum indicates heterogeneity in the principal virulence factor, the 57 kDa protein. JOURNAL OF FISH DISEASES 2022; 45:1173-1188. [PMID: 35604683 DOI: 10.1111/jfd.13653] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 04/28/2022] [Accepted: 05/02/2022] [Indexed: 06/15/2023]
Abstract
Renibacterium salmoninarum, a Gram-positive intracellular pathogen, is the causative agent of bacterial kidney disease (BKD), the impacts of which are high mortalities and economic losses for the salmon industry. This study provides novel analyses for the whole-genome sequences of 50 R. salmoninarum isolates and the reference strain ATCC 33209 using a pan-genomic approach to elucidate phylogenomic relationships and identify unique and shared genes associated with pathogenicity and infection mechanisms. Genome size varied from 3,061,638 to 3,155,332 bp; gene count from 3452 to 3580; and predicted coding sequences from 3402 to 3527. Comparative analyses revealed an open, but approaching closed, pan-genome. The pan-genome analysis recovered 4064 genes, with a core genome containing 3306 genes. Phylogenetic analysis of R. salmoninarum showed high genomic homogeneity, apart from one isolate obtained from Salmo trutta in Norway. All genomes presented the 57-kDa protein (p57). Strain ATCC 33209 and the Chilean isolates H-2 and DJ2R presented two copies of the msa gene, while the remaining isolates had one copy. The pan-genome analysis further identified differences in the number of copies and length of the signalling peptide for p57, the principal virulence factor reported for this bacterium. This heterogeneity could be associated with the secretion levels of p57, potentially influencing virulence. Additionally identified were numerous common genes related to iron uptake, the stress response and regulation, and cell signalling-all of which constitute the pathogenic repertoire of R. salmoninarum. This investigation provides information that is applicable in future studies for identifying therapeutic targets and/or for designing new strategies (e.g., vaccines) to prevent BKD infections in salmon farming.
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Affiliation(s)
- Mónica Saldarriaga-Córdoba
- Centro de Investigación en Recursos Naturales y Sustentabilidad, Universidad Bernardo O'Higgins, Santiago, Chile
- Centro FONDAP, Interdisciplinary Center for Aquaculture Research (INCAR), Universidad Andrés Bello, Viña del Mar, Chile
| | - Ruben Avendaño-Herrera
- Centro FONDAP, Interdisciplinary Center for Aquaculture Research (INCAR), Universidad Andrés Bello, Viña del Mar, Chile
- Laboratorio de Patología de Organismos Acuáticos y Biotecnología Acuícola, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Viña del Mar, Chile
- Centro de Investigaciones Marina Quintay (CIMARQ), Universidad Andés Bello, Quintay, Chile
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11
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Wang J, Chen Z, Xu W, Li Y, Lu S, Wang L, Song Y, Wang N, Gong Z, Yang Q, Chen S. Transcriptomic analysis reveals the gene expression profiles in the spleen of spotted knifejaw (Oplegnathus punctatus) infected by Vibrio harveyi. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2022; 133:104432. [PMID: 35533850 DOI: 10.1016/j.dci.2022.104432] [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: 02/19/2022] [Revised: 05/02/2022] [Accepted: 05/03/2022] [Indexed: 06/14/2023]
Abstract
As one of the most valuable maricultured species, spotted knifejaw (Oplegnathus punctatus) has high popularity in eastern Asia. In recent years, diseases caused by Vibrio harveyi have brought huge economic losses in spotted knifejaw industry. To better understand the molecular mechanisms of immune response about V. harveyi resistance in spotted knifejaw, a comparative transcriptome analysis was performed on spleen tissues at five different time points post-infection (0, 12, 24, 48 and 72 hpi). A total of 4279 differentially expressed genes (DEGs) were identified. KEGG pathways analysis showed that multiple immune-related pathways were significant regulated, including Toll-like receptor signaling pathway, ECM-receptor interaction pathway, cytokine-cytokine receptor interaction pathway and hematopoietic cell lineage pathway. Weighted gene co-expression network analysis showed that several immune-related pathways of the highest correlation with 12 hpi (cor = 0.89, P = 7e-06) were significantly enriched. In addition, 12 hpi was a turning point for 7 gene clusters out of 9 that were divided according to gene expression patterns. Therefore, we speculated that 12 hpi might be a very critical time point for spotted knifejaw against V. harveyi infection. Additionally, qRT-PCR was carried out to validate the expressions of 12 DEGs. This study provided the first systematical transcriptome analysis of spotted knifejaw against V. harveyi. The results could help us better understand the dynamic immune responses of spotted knifejaw against bacterial infection, and provide useful information for antibacterial defense in spotted knifejaw industry as well.
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Affiliation(s)
- Jie Wang
- College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, 201306, China; Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China
| | - Zhangfan Chen
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China; Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao, 266071, China; Shandong Key Laboratory of Marine Fisheries Biotechnology and Genetic Breeding, Qingdao, 266071, China
| | - Wenteng Xu
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China; Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao, 266071, China; Shandong Key Laboratory of Marine Fisheries Biotechnology and Genetic Breeding, Qingdao, 266071, China
| | - Yangzhen Li
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China; Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao, 266071, China; Shandong Key Laboratory of Marine Fisheries Biotechnology and Genetic Breeding, Qingdao, 266071, China
| | - Sheng Lu
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China
| | - Lei Wang
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China; Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao, 266071, China; Shandong Key Laboratory of Marine Fisheries Biotechnology and Genetic Breeding, Qingdao, 266071, China
| | - Yu Song
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China
| | - Na Wang
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China; Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao, 266071, China; Shandong Key Laboratory of Marine Fisheries Biotechnology and Genetic Breeding, Qingdao, 266071, China
| | - Zhihong Gong
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China
| | - Qian Yang
- College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, 201306, China; Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China
| | - Songlin Chen
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China; Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao, 266071, China; Shandong Key Laboratory of Marine Fisheries Biotechnology and Genetic Breeding, Qingdao, 266071, China.
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12
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Chen H, Zhao Y, Chen K, Wei Y, Luo H, Li Y, Liu F, Zhu Z, Hu W, Luo D. Isolation, Identification, and Investigation of Pathogenic Bacteria From Common Carp (Cyprinus carpio) Naturally Infected With Plesiomonas shigelloides. Front Immunol 2022; 13:872896. [PMID: 35844551 PMCID: PMC9279890 DOI: 10.3389/fimmu.2022.872896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 06/01/2022] [Indexed: 11/27/2022] Open
Abstract
Various bacterial diseases have caused great economic losses to the high-density and intensive aquaculture industry; however, the pathogenic mechanism underlying the large-scale challenged to caused by many bacteria remain unclear, making the prevention and treatment of these diseases difficult. In the present study, we isolated a bacterial strain from Cyprinus carpio having a typical bacterial disease and named it Cc2021. Through subsequent morphological observations, a regression challenge, biochemical identification, and 16S rRNA gene sequence analysis, we determined Cc2021 to be Plesiomonas shigelloides. Subsequently, we comprehensively investigated the pathogenicity of P. shigelloides in C. carpio through a regression challenge and assessed the underlying the pathogenic mechanism. Mortality results revealed that P. shigelloides is highly pathogenic and infects various tissues throughout the body, resulting in edema of the liver, spleen, and body and head kidneys. Histopathological analysis revealed obvious inflammation, bleeding, and necrosis in the intestine, spleen, and head kidney. The body’s immune tissues actively produce complement C3, superoxide dismutase, and lysozyme after a challenge to resist bacterial invasion. With regard to the underlying pathogenesis of P. shigelloides, comparative transcriptome analysis revealed 876 upregulated genes and 828 downregulated genes in the intestine of C. carpio after the challenge. Analysis of differentially expressed unigenes revealed the involvement of major immune pathways, particularly the TNF signaling pathway, interleukin (IL)-17 signaling pathway, and Toll-like receptor signaling pathway. The present study provides new valuable information on the immune system and defense mechanisms of P. shigelloides.
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Affiliation(s)
- Huijie Chen
- State Key Laboratory of Freshwater Ecology and Biotechnology, Hubei Hongshan Laboratory, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, China
- College of Fisheries, Huazhong Agricultural University, Wuhan, China
| | - Yuanli Zhao
- State Key Laboratory of Freshwater Ecology and Biotechnology, Hubei Hongshan Laboratory, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, China
| | - Kuangxin Chen
- State Key Laboratory of Freshwater Ecology and Biotechnology, Hubei Hongshan Laboratory, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yulai Wei
- State Key Laboratory of Freshwater Ecology and Biotechnology, Hubei Hongshan Laboratory, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Hongrui Luo
- State Key Laboratory of Freshwater Ecology and Biotechnology, Hubei Hongshan Laboratory, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, China
| | - Yongming Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Hubei Hongshan Laboratory, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, China
| | - Fei Liu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Hubei Hongshan Laboratory, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Zuoyan Zhu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Hubei Hongshan Laboratory, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, China
| | - Wei Hu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Hubei Hongshan Laboratory, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, China
| | - Daji Luo
- State Key Laboratory of Freshwater Ecology and Biotechnology, Hubei Hongshan Laboratory, Institute of Hydrobiology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, China
- College of Fisheries, Huazhong Agricultural University, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
- *Correspondence: Daji Luo,
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13
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Persson DB, Aspán A, Hysing P, Blomkvist E, Jansson E, Orsén L, Hällbom H, Axén C. Assessing the presence and spread of Renibacterium salmoninarum between farmed and wild fish in Sweden. JOURNAL OF FISH DISEASES 2022; 45:613-621. [PMID: 35092707 PMCID: PMC9304202 DOI: 10.1111/jfd.13586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 01/10/2022] [Accepted: 01/14/2022] [Indexed: 06/14/2023]
Abstract
Bacterial kidney disease (BKD) can be a devastating bacterial infection in salmonids, and it is present in aquaculture throughout the world. BKD is caused by the Gram-positive facultative intracellular bacterium Renibacterium salmoninarum (R. salmoninarum) that is spread both horizontally and vertically. Disease signs include external ulcerations and blisters and internal signs such as organ swelling, granulomas, petechiae and ascites. In Sweden, BKD accounts for a significant income loss in aquacultures due to expensive decontamination of the facility and increased disease susceptibility for the immunocompromised fish leading to higher mortality rates. In addition, uncontrolled spread in aquaculture may threaten the survival of wild fish populations. The aim of our study was to investigate the prevalence of R. salmoninarum in wild salmonids caught in Swedish waters where net pen farms with a recent history of BKD are present. Four rivers with at least one BKD-positive or recently BKD-positive farm were selected. In addition, we evaluated the use of environmental DNA (eDNA) for surveillance and monitoring of ongoing infections at these locations. In total, 1058 fish were sampled from four different river systems, and of them 52 (4.9%) were positive for R. salmoninarum by antigen ELISA. Surprisingly, these fish were not evenly distributed between the four river systems, but 50 were caught in the same river (Ljungan). This accounts for an alarmingly high rate of 17% R. salmoninarum-positive samples in wild salmonids in this area. This number is far above what was expected and clearly shows the risk with an open farming system as well as the importance of effective health monitoring programmes to avoid an uncontrolled spread of the disease. The use of eDNA for monitoring BKD is somewhat difficult to evaluate. Few of the water samples analysed were PCR positive for R. salmoninarum (2 of 38) and those were collected where no ELISA positive fish were identified. In addition to water, sediment samples were collected under a net pen farm that had recently slaughtered all fish due to ongoing R. salmoninarum infections. Sediment samples are more promising than water as 4 of 5 samples at one farming facility where positive for R. salmoninarum. Thus, sediment samples may be valuable for monitoring potential ongoing BKD in farms, without the need to sacrifice valuable fish.
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Affiliation(s)
| | - Anna Aspán
- National Veterinary InstituteUppsalaSweden
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14
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Caballero-Solares A, Umasuthan N, Xue X, Katan T, Kumar S, Westcott JD, Chen Z, Fast MD, Skugor S, Taylor RG, Rise ML. Interacting Effects of Sea Louse (Lepeophtheirus salmonis) Infection and Formalin-Killed Aeromonas salmonicida on Atlantic Salmon Skin Transcriptome. Front Immunol 2022; 13:804987. [PMID: 35401509 PMCID: PMC8987027 DOI: 10.3389/fimmu.2022.804987] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 02/21/2022] [Indexed: 11/13/2022] Open
Abstract
Lepeophtheirus salmonis (sea lice) and bacterial co-infection threatens wild and farmed Atlantic salmon performance and welfare. In the present study, pre-adult L. salmonis-infected and non-infected salmon were intraperitoneally injected with either formalin-killed Aeromonas salmonicida bacterin (ASAL) or phosphate-buffered saline (PBS). Dorsal skin samples from each injection/infection group (PBS/no lice, PBS/lice, ASAL/no lice, and ASAL/lice) were collected at 24 h post-injection and used for transcriptome profiling using a 44K salmonid microarray platform. Microarray results showed no clear inflammation gene expression signatures and revealed extensive gene repression effects by pre-adult lice (2,189 down and 345 up-regulated probes) in the PBS-injected salmon (PBS/lice vs. PBS/no lice), which involved basic cellular (e.g., RNA and protein metabolism) processes. Lice repressive effects were not observed within the group of ASAL-injected salmon (ASAL/lice vs. ASAL/no lice); on the contrary, the observed skin transcriptome changes –albeit of lesser magnitude (82 up and 1 down-regulated probes)– suggested the activation in key immune and wound healing processes (e.g., neutrophil degranulation, keratinocyte differentiation). The molecular skin response to ASAL was more intense in the lice-infected (ASAL/lice vs. PBS/lice; 272 up and 11 down-regulated probes) than in the non-infected fish (ASAL/no lice vs. PBS/no lice; 27 up-regulated probes). Regardless of lice infection, the skin’s response to ASAL was characterized by the putative activation of both antibacterial and wound healing pathways. The transcriptomic changes prompted by ASAL+lice co-stimulation (ASAL/lice vs. PBS/no lice; 1878 up and 3120 down-regulated probes) confirmed partial mitigation of lice repressive effects on fundamental cellular processes and the activation of pathways involved in innate (e.g., neutrophil degranulation) and adaptive immunity (e.g., antibody formation), as well as endothelial cell migration. The qPCR analyses evidenced immune-relevant genes co-stimulated by ASAL and lice in an additive (e.g., mbl2b, bcl6) and synergistic (e.g., hampa, il4r) manner. These results provided insight on the physiological response of the skin of L. salmonis-infected salmon 24 h after ASAL stimulation, which revealed immunostimulatory properties by the bacterin with potential applications in anti-lice treatments for aquaculture. As a simulated co-infection model, the present study also serves as a source of candidate gene biomarkers for sea lice and bacterial co-infection.
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Affiliation(s)
- Albert Caballero-Solares
- Department of Ocean Sciences, Memorial University, St. John’s, NL, Canada
- *Correspondence: Albert Caballero-Solares,
| | | | - Xi Xue
- Department of Ocean Sciences, Memorial University, St. John’s, NL, Canada
| | - Tomer Katan
- Department of Ocean Sciences, Memorial University, St. John’s, NL, Canada
| | - Surendra Kumar
- Department of Ocean Sciences, Memorial University, St. John’s, NL, Canada
| | | | - Zhiyu Chen
- Department of Ocean Sciences, Memorial University, St. John’s, NL, Canada
- Fisheries and Marine Institute, Memorial University, St. John’s, NL, Canada
| | - Mark D. Fast
- Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada
| | - Stanko Skugor
- Cargill Aqua Nutrition, Cargill, Sea Lice Research Center (SLRC), Sandnes, Norway
| | | | - Matthew L. Rise
- Department of Ocean Sciences, Memorial University, St. John’s, NL, Canada
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15
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Eslamloo K, Kumar S, Xue X, Parrish KS, Purcell SL, Fast MD, Rise ML. Global gene expression responses of Atlantic salmon skin to Moritella viscosa. Sci Rep 2022; 12:4622. [PMID: 35301338 PMCID: PMC8931016 DOI: 10.1038/s41598-022-08341-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Accepted: 03/03/2022] [Indexed: 12/19/2022] Open
Abstract
Moritella viscosa is a Gram-negative pathogen that causes large, chronic ulcers, known as winter-ulcer disease, in the skin of several fish species including Atlantic salmon. We used a bath challenge approach to profile the transcriptome responses of M. viscosa-infected Atlantic salmon skin at the lesion (Mv-At) and away from the lesion (Mv-Aw) sites. M. viscosa infection was confirmed through RNA-based qPCR assays. RNA-Seq identified 5212 and 2911 transcripts differentially expressed in the Mv-At compared to no-infection control and Mv-Aw groups, respectively. Also, there were 563 differentially expressed transcripts when comparing the Mv-Aw to control samples. Our results suggest that M. viscosa caused massive and strong, but largely infection site-focused, transcriptome dysregulations in Atlantic salmon skin, and its effects beyond the skin lesion site were comparably subtle. The M. viscosa-induced transcripts of Atlantic salmon were mainly involved in innate and adaptive immune response-related pathways, whereas the suppressed transcripts by this pathogen were largely connected to developmental and cellular processes. As validated by qPCR, M. viscosa dysregulated transcripts encoding receptors, signal transducers, transcription factors and immune effectors playing roles in TLR- and IFN-dependent pathways as well as immunoregulation, antigen presentation and T-cell development. This study broadened the current understanding of molecular pathways underlying M. viscosa-triggered responses of Atlantic salmon, and identified biomarkers that may assist to diagnose and combat this pathogen.
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Affiliation(s)
- Khalil Eslamloo
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada. .,Hoplite Laboratory, Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PEI, Canada.
| | - Surendra Kumar
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Xi Xue
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Kathleen S Parrish
- Hoplite Laboratory, Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PEI, Canada
| | - Sara L Purcell
- Hoplite Laboratory, Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PEI, Canada
| | - Mark D Fast
- Hoplite Laboratory, Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PEI, Canada
| | - Matthew L Rise
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
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16
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Xue X, Caballero-Solares A, Hall JR, Umasuthan N, Kumar S, Jakob E, Skugor S, Hawes C, Santander J, Taylor RG, Rise ML. Transcriptome Profiling of Atlantic Salmon ( Salmo salar) Parr With Higher and Lower Pathogen Loads Following Piscirickettsia salmonis Infection. Front Immunol 2022; 12:789465. [PMID: 35035387 PMCID: PMC8758579 DOI: 10.3389/fimmu.2021.789465] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 12/03/2021] [Indexed: 12/29/2022] Open
Abstract
Salmonid rickettsial septicemia (SRS), caused by Piscirickettsia salmonis, is one of the most devastating diseases of salmonids. However, the transcriptomic responses of Atlantic salmon (Salmon salar) in freshwater to an EM-90-like isolate have not been explored. Here, we infected Atlantic salmon parr with an EM-90-like isolate and conducted time-course qPCR analyses of pathogen load and four biomarkers (campb, hampa, il8a, tlr5a) of innate immunity on the head kidney samples. Transcript expression of three of these genes (except hampa), as well as pathogen level, peaked at 21 days post-injection (DPI). Multivariate analyses of infected individuals at 21 DPI revealed two infection phenotypes [lower (L-SRS) and higher (H-SRS) infection level]. Five fish from each group (Control, L-SRS, and H-SRS) were selected for transcriptome profiling using a 44K salmonid microarray platform. We identified 1,636 and 3,076 differentially expressed probes (DEPs) in the L-SRS and H-SRS groups compared with the control group, respectively (FDR = 1%). Gene ontology term enrichment analyses of SRS-responsive genes revealed the activation of a large number of innate (e.g. “phagocytosis”, “defense response to bacterium”, “inflammatory response”) and adaptive (e.g. “regulation of T cell activation”, “antigen processing and presentation of exogenous antigen”) immune processes, while a small number of general physiological processes (e.g. “apoptotic process”, development and metabolism relevant) was enriched. Transcriptome results were confirmed by qPCR analyses of 42 microarray-identified transcripts. Furthermore, the comparison of individuals with differing levels of infection (H-SRS vs. L-SRS) generated insights into the biological processes possibly involved in disease resistance or susceptibility. This study demonstrated a low mortality (~30%) EM-90-like infection model and broadened the current understanding of molecular pathways underlying P. salmonis-triggered responses of Atlantic salmon, identifying biomarkers that may assist to diagnose and combat this pathogen.
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Affiliation(s)
- Xi Xue
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
| | | | - Jennifer R Hall
- Aquatic Research Cluster, CREAIT Network, Ocean Sciences Centre, Memorial University of Newfoundland, St. John's, NL, Canada
| | | | - Surendra Kumar
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Eva Jakob
- Cargill Innovation Centre - Colaco, Colaco, Chile
| | - Stanko Skugor
- Cargill Aqua Nutrition, Cargill, Sea Lice Research Center (SLRC), Sandnes, Norway
| | | | - Javier Santander
- Marine Microbial Pathogenesis and Vaccinology Lab, Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Richard G Taylor
- Cargill Animal Nutrition and Health, Elk River, MN, United States
| | - Matthew L Rise
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
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Gnanagobal H, Cao T, Hossain A, Dang M, Hall JR, Kumar S, Van Cuong D, Boyce D, Santander J. Lumpfish ( Cyclopterus lumpus) Is Susceptible to Renibacterium salmoninarum Infection and Induces Cell-Mediated Immunity in the Chronic Stage. Front Immunol 2021; 12:733266. [PMID: 34880856 PMCID: PMC8645940 DOI: 10.3389/fimmu.2021.733266] [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: 06/30/2021] [Accepted: 10/19/2021] [Indexed: 02/02/2023] Open
Abstract
Renibacterium salmoninarum is a Gram-positive, intracellular pathogen that causes Bacterial Kidney Disease (BKD) in several fish species in freshwater and seawater. Lumpfish (Cyclopterus lumpus) is utilized as a cleaner fish to biocontrol sea lice infestation in Atlantic salmon (Salmo salar) farms. Atlantic salmon is susceptible to R. salmoninarum, and it can transfer the infection to other fish species. Although BKD outbreaks have not been reported in lumpfish, its susceptibility and immune response to R. salmoninarum is unknown. In this study, we evaluated the susceptibility and immune response of lumpfish to R. salmoninarum infection. Groups of lumpfish were intraperitoneally (i.p.) injected with either R. salmoninarum (1×107, 1×108, or 1×109 cells dose-1) or PBS (control). R. salmoninarum infection kinetics and mortality were followed for 98 days post-infection (dpi). Transcript expression levels of 33 immune-relevant genes were measured in head kidney (n = 6) of fish infected with 1×109 cells/dose and compared to the control at 28 and 98 dpi. Infected lumpfish displayed characteristic clinical signs of BKD. Lumpfish infected with high, medium, and low doses had a survival rate of 65%, 93%, and 95%, respectively. Mortality in the high-dose infected group stabilized after 50 dpi, but R. salmoninarum persisted in the fish tissues until 98 dpi. Cytokines (il1β, il8a, il8b), pattern recognition receptors (tlr5a), interferon-induced effectors (rsad2, mxa, mxb, mxc), and iron regulation (hamp) and acute phase reactant (saa5) related genes were up-regulated at 28 dpi. In contrast, cell-mediated adaptive immunity-related genes (cd4a, cd4b, ly6g6f, cd8a, cd74) were down-regulated at 28 dpi, revealing the immune suppressive nature of R. salmoninarum. However, significant upregulation of cd74 at 98 dpi suggests induction of cell-mediated immune response. This study showed that R. salmoninarum infected lumpfish in a similar fashion to salmonid fish species and caused a chronic infection, enhancing cell-mediated adaptive immune response.
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Affiliation(s)
- Hajarooba Gnanagobal
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada.,Department of Bio-systems Technology, Faculty of Technology, University of Jaffna, Kilinochchi, Sri Lanka
| | - Trung Cao
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Ahmed Hossain
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
| | - My Dang
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Jennifer R Hall
- Aquatic Research Cluster, CREAIT Network, Ocean Sciences Centre, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Surendra Kumar
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada.,Ocean Frontier Institute, Ocean Sciences Centre, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Doan Van Cuong
- Southern Monitoring Center for Aquaculture Environment and Epidemic (MCE), Research Institute for Aquaculture No. 2, Ho Chi Minh City, Vietnam
| | - Danny Boyce
- The Dr. Joe Brown Aquatic Research Building (JBARB), Ocean Sciences Centre, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Javier Santander
- Marine Microbial Pathogenesis and Vaccinology Laboratory, Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
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Lv Z, Hu Y, Tan J, Wang X, Liu X, Zeng C. Comparative Transcriptome Analysis Reveals the Molecular Immunopathogenesis of Chinese Soft-Shelled Turtle ( Trionyx sinensis) Infected with Aeromonas hydrophila. BIOLOGY 2021; 10:biology10111218. [PMID: 34827211 PMCID: PMC8615003 DOI: 10.3390/biology10111218] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 11/18/2021] [Accepted: 11/19/2021] [Indexed: 02/08/2023]
Abstract
Simple Summary The Chinese soft-shelled turtle (Trionyx sinensis) is an important cultured reptile in East Asia. Hemorrhagic sepsis caused by Aeromonas hydrophila infection is the dominant disease in the aquaculture of Chinese soft-shelled turtles, while the molecular pathology is far from clear due to the lag of research on turtle immunology. It has been reported in mammals and fish that the dysfunction of immune responses to pathogen infections causes host tissue hemorrhagic sepsis. In this study, two groups of turtles with different susceptibility to A. hydrophila infection are found. A comparative transcriptome strategy is adopted to examine the gene expression profiles in liver and spleen for these two phenotypes of turtles post A. hydrophila infection, for the first time revealing the full picture of immune mechanisms against A. hydrophila, which provides new insight into the molecular pathology during A. hydrophila infection in T. sinensis. The findings will promote further investigations on pathogenic mechanisms of hemorrhagic sepsis caused by A. hydrophila infection in T. sinensis, and also will benefit their culture industry. Abstract Although hemorrhagic sepsis caused by Aeromonas hydrophila infection is the dominant disease in the aquaculture of Chinese soft-shelled turtle, information on its molecular pathology is seriously limited. In this study, ninety turtles intraperitoneally injected with A. hydrophila exhibited two different phenotypes based on the pathological symptoms, referred to as active and inactive turtles. Comparative transcriptomes of liver and spleen from these two groups at 6, 24, and 72 h post-injection (hpi) were further analyzed. The results showed that cytokine–cytokine receptor interaction, PRRs mediated signaling pathway, apoptosis, and phagocytosis enriched in active and inactive turtles were significantly different. Pro-inflammatory cytokines, the TLR signaling pathway, NLR signaling pathway, and RLR signaling pathway mediating cytokine expression, and apoptosis-related genes, were significantly up-regulated in inactive turtles at the early stage (6 hpi). The significant up-regulation of phagocytosis-related genes occurred at 24 hpi in inactive turtles and relatively lagged behind those in active turtles. The anti-inflammatory cytokine, IL10, was significantly up-regulated during the tested periods (6, 24, and 72 hpi) in active turtles. These findings offer valuable information for the understanding of molecular immunopathogenesis after A. hydrophila infection, and facilitate further investigations on strategies against hemorrhagic sepsis in Chinese soft-shelled turtle T. sinensis.
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Affiliation(s)
- Zhao Lv
- Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha 410128, China; (Z.L.); (Y.H.); (J.T.); (X.W.); (X.L.)
| | - Yazhou Hu
- Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha 410128, China; (Z.L.); (Y.H.); (J.T.); (X.W.); (X.L.)
| | - Jin Tan
- Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha 410128, China; (Z.L.); (Y.H.); (J.T.); (X.W.); (X.L.)
| | - Xiaoqing Wang
- Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha 410128, China; (Z.L.); (Y.H.); (J.T.); (X.W.); (X.L.)
| | - Xiaoyan Liu
- Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha 410128, China; (Z.L.); (Y.H.); (J.T.); (X.W.); (X.L.)
| | - Cong Zeng
- School of Oceanography, Shanghai Jiao Tong University, Shanghai 200240, China
- Correspondence:
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Smith NC, Umasuthan N, Kumar S, Woldemariam NT, Andreassen R, Christian SL, Rise ML. Transcriptome Profiling of Atlantic Salmon Adherent Head Kidney Leukocytes Reveals That Macrophages Are Selectively Enriched During Culture. Front Immunol 2021; 12:709910. [PMID: 34484211 PMCID: PMC8415484 DOI: 10.3389/fimmu.2021.709910] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 07/05/2021] [Indexed: 01/23/2023] Open
Abstract
The Atlantic salmon (Salmo salar) is an economically important fish, both in aquaculture and in the wild. In vertebrates, macrophages are some of the first cell types to respond to pathogen infection and disease. While macrophage biology has been characterized in mammals, less is known in fish. Our previous work identified changes in the morphology, phagocytic ability, and miRNA profile of Atlantic salmon adherent head kidney leukocytes (HKLs) from predominantly “monocyte-like” at Day 1 of in vitro culture to predominantly “macrophage-like” at Day 5 of culture. Therefore, to further characterize these two cell populations, we examined the mRNA transcriptome profile in Day 1 and Day 5 HKLs using a 44K oligonucleotide microarray. Large changes in the transcriptome were revealed, including changes in the expression of macrophage and immune-related transcripts (e.g. csf1r, arg1, tnfa, mx2), lipid-related transcripts (e.g. fasn, dhcr7, fabp6), and transcription factors involved in macrophage differentiation and function (e.g. klf2, klf9, irf7, irf8, stat1). The in silico target prediction analysis of differentially expressed genes (DEGs) using miRNAs known to change expression in Day 5 HKLs, followed by gene pathway enrichment analysis, supported that these miRNAs may be involved in macrophage maturation by targeting specific DEGs. Elucidating how immune cells, such as macrophages, develop and function is a key step in understanding the Atlantic salmon immune system. Overall, the results indicate that, without the addition of exogenous factors, the adherent HKL cell population differentiates in vitro to become macrophage-like.
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Affiliation(s)
- Nicole C Smith
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
| | | | - Surendra Kumar
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Nardos T Woldemariam
- Department of Life Sciences and Health, OsloMet-Oslo Metropolitan University, Oslo, Norway
| | - Rune Andreassen
- Department of Life Sciences and Health, OsloMet-Oslo Metropolitan University, Oslo, Norway
| | - Sherri L Christian
- Department of Biochemistry, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Matthew L Rise
- Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
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