1
|
Lee B, Lee J, Lim S, Seong M, Yun H, Han S, Kim KW, Lee S, Jeong SM, Park MC, Hong WS, Kwon SR, Park Y. Effects of Low-Lipid Diets on Growth, Haematology, Histology and Immune Responses of Parr-Stage Atlantic Salmon ( Salmo salar). Animals (Basel) 2024; 14:1581. [PMID: 38891628 PMCID: PMC11171226 DOI: 10.3390/ani14111581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Revised: 05/23/2024] [Accepted: 05/23/2024] [Indexed: 06/21/2024] Open
Abstract
Lipids in fish diets provide energy and play important roles in immunity and metabolism. Atlantic salmon, a species that migrates from freshwater to seawater, requires high energy, especially during smoltification. Juvenile teleosts have low lipid requirements, and a high dietary lipid content is known to have negative effects on their growth and digestion. Therefore, this study evaluated the effect of two commercial rainbow trout feeds (low-lipid, 13.41% and 14.6%) on the growth and immune responses of early parr-stage Atlantic salmon compared to commercial salmon feed (high-lipid, 29.52%). Atlantic salmon parr (weight: 14.56 ± 2.1 g; length: 11.23 ± 0.44 cm) were randomly divided into three groups and fed either one of two commercial rainbow trout feeds (RTF1 and RTF2) or the commercial salmon feed (ASF) for 12 weeks. At the end of the feeding trial, growth, haematology, histology and gene expression analyses were performed. There were no significant differences in weight gain rates or feed efficiency between the groups (p > 0.05). Superoxidate dismutase, glutathione peroxidase, lysozyme and immunoglobulin M activities were not different among the experimental groups (p > 0.05). A histological examination of the liver and intestinal tissues showed no pathological symptoms of inflammatory response or lipid accumulation in any of the groups. In an intestinal transcriptome analysis using RNA-seq, the expression levels of several genes linked to lipids, immune-related proteins, cytokines and chemokines did not differ significantly between the groups (p > 0.05). Commercial rainbow trout feed with low lipid content has no clear negative impact on the development of Atlantic salmon during the early parr stage (14.5 to 39.6 g). This study provides basic information for the development of economical feed for early parr-stage Atlantic salmon.
Collapse
Affiliation(s)
- Byoungyoon Lee
- Department of Aquatic Life Medical Sciences, Sunmoon University, Asan 31460, Republic of Korea; (B.L.); (J.L.); (S.L.); (M.S.); (H.Y.); (S.H.); (S.R.K.)
| | - Junoh Lee
- Department of Aquatic Life Medical Sciences, Sunmoon University, Asan 31460, Republic of Korea; (B.L.); (J.L.); (S.L.); (M.S.); (H.Y.); (S.H.); (S.R.K.)
| | - Saeyeon Lim
- Department of Aquatic Life Medical Sciences, Sunmoon University, Asan 31460, Republic of Korea; (B.L.); (J.L.); (S.L.); (M.S.); (H.Y.); (S.H.); (S.R.K.)
| | - Minjae Seong
- Department of Aquatic Life Medical Sciences, Sunmoon University, Asan 31460, Republic of Korea; (B.L.); (J.L.); (S.L.); (M.S.); (H.Y.); (S.H.); (S.R.K.)
| | - Hanbin Yun
- Department of Aquatic Life Medical Sciences, Sunmoon University, Asan 31460, Republic of Korea; (B.L.); (J.L.); (S.L.); (M.S.); (H.Y.); (S.H.); (S.R.K.)
| | - Sijun Han
- Department of Aquatic Life Medical Sciences, Sunmoon University, Asan 31460, Republic of Korea; (B.L.); (J.L.); (S.L.); (M.S.); (H.Y.); (S.H.); (S.R.K.)
| | - Kang-Woong Kim
- Aquafeed Research Center, National Institute of Fisheries Science (NIFS), Pohang 37517, Republic of Korea; (K.-W.K.); (S.L.); (S.-M.J.)
| | - Seunghan Lee
- Aquafeed Research Center, National Institute of Fisheries Science (NIFS), Pohang 37517, Republic of Korea; (K.-W.K.); (S.L.); (S.-M.J.)
| | - Seong-Mok Jeong
- Aquafeed Research Center, National Institute of Fisheries Science (NIFS), Pohang 37517, Republic of Korea; (K.-W.K.); (S.L.); (S.-M.J.)
| | - Mun Chang Park
- Gangwon State Inland Water Resource Center, Chuncheon 24210, Republic of Korea; (M.C.P.); (W.S.H.)
| | - Woo Seok Hong
- Gangwon State Inland Water Resource Center, Chuncheon 24210, Republic of Korea; (M.C.P.); (W.S.H.)
| | - Se Ryun Kwon
- Department of Aquatic Life Medical Sciences, Sunmoon University, Asan 31460, Republic of Korea; (B.L.); (J.L.); (S.L.); (M.S.); (H.Y.); (S.H.); (S.R.K.)
| | - Youngjin Park
- Department of Aquatic Life Medical Sciences, Sunmoon University, Asan 31460, Republic of Korea; (B.L.); (J.L.); (S.L.); (M.S.); (H.Y.); (S.H.); (S.R.K.)
| |
Collapse
|
2
|
Kortner TM, Afanasyev S, Koppang EO, Bjørgen H, Krogdahl Å, Krasnov A. A comprehensive transcriptional body map of Atlantic salmon unveils the vital role of the intestine in the immune system and highlights functional specialization within its compartments. FISH & SHELLFISH IMMUNOLOGY 2024; 146:109422. [PMID: 38307300 DOI: 10.1016/j.fsi.2024.109422] [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: 12/14/2023] [Revised: 01/25/2024] [Accepted: 01/31/2024] [Indexed: 02/04/2024]
Abstract
The intestine is a barrier organ that plays an important role in the immune system of Atlantic salmon. The immune functions are distributed among the diffuse gut lymphoid tissue containing diverse immune cells, and other cell types. Comparison of intestinal transcriptomes with those of other organs and tissues offers an opportunity to elucidate the specific roles of the intestine and its relationship with other parts of the body. In this work, a meta-analysis was performed on a large volume of data obtained using a genome-wide DNA oligonucleotide microarray. The intestine ranks third by the expression level of immune genes after the spleen and head kidney. The activity of antigen presentation and innate antiviral immunity is higher in the intestine than in any other tissue. By comparing transcriptome profiles, intestine shows the greatest similarity with the gill, head kidney, spleen, epidermis, and olfactory rosette (descending order), which emphasizes the integrity of the peripheral mucosal system and its strong connections with the major lymphoid organs. T cells-specific genes dominate among the genes co-expressed in these tissues. The transcription signature of CD8+ (86 genes, r > 0.9) includes a master gene of immune tolerance foxp3 and other negative regulators. Different segments of the intestine were compared in a separate experiment, in which expression gradients along the intestine were found across several functional groups of genes. The expression of luminal and intracellular (lysosome) proteases is markedly higher in pyloric caeca and distal intestine respectively. Steroid metabolism and cytochromes P450 are highly expressed in pyloric caeca and mid intestine while the distal intestine harbors genes related to vitamin and iron metabolism. The expression of genes for antigen presenting proteins and immunoglobulins shows a gradual increase towards the distal intestine.
Collapse
Affiliation(s)
- Trond M Kortner
- Norwegian University of Life Sciences, Faculty of Veterinary Medicine, Ås, Norway.
| | - Sergey Afanasyev
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Saint Petersburg, Russia
| | - Erling Olaf Koppang
- Norwegian University of Life Sciences, Faculty of Veterinary Medicine, Ås, Norway
| | - Håvard Bjørgen
- Norwegian University of Life Sciences, Faculty of Veterinary Medicine, Ås, Norway
| | - Åshild Krogdahl
- Norwegian University of Life Sciences, Faculty of Veterinary Medicine, Ås, Norway
| | | |
Collapse
|
3
|
Sun J, Ruiz Daniels R, Balic A, Andresen AMS, Bjørgen H, Dobie R, Henderson NC, Koppang EO, Martin SAM, Fosse JH, Taylor RS, Macqueen DJ. Cell atlas of the Atlantic salmon spleen reveals immune cell heterogeneity and cell-specific responses to bacterial infection. FISH & SHELLFISH IMMUNOLOGY 2024; 145:109358. [PMID: 38176627 DOI: 10.1016/j.fsi.2024.109358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 12/23/2023] [Accepted: 01/02/2024] [Indexed: 01/06/2024]
Abstract
The spleen is a conserved secondary lymphoid organ that emerged in parallel to adaptive immunity in early jawed vertebrates. Recent studies have applied single cell transcriptomics to reveal the cellular composition of spleen in several species, cataloguing diverse immune cell types and subpopulations. In this study, 51,119 spleen nuclei transcriptomes were comprehensively investigated in the commercially important teleost Atlantic salmon (Salmo salar L.), contrasting control animals with those challenged with the bacterial pathogen Aeromonas salmonicida. We identified clusters of nuclei representing the expected major cell types, namely T cells, B cells, natural killer-like cells, granulocytes, mononuclear phagocytes, endothelial cells, mesenchymal cells, erythrocytes and thrombocytes. We discovered heterogeneity within several immune lineages, providing evidence for resident macrophages and melanomacrophages, infiltrating monocytes, several candidate dendritic cell subpopulations, and B cells at distinct stages of differentiation, including plasma cells and an igt + subset. We provide evidence for twelve candidate T cell subsets, including cd4+ T helper and regulatory T cells, one cd8+ subset, three γδT subsets, and populations double negative for cd4 and cd8. The number of genes showing differential expression during the early stages of Aeromonas infection was highly variable across immune cell types, with the largest changes observed in macrophages and infiltrating monocytes, followed by resting mature B cells. Our analysis provides evidence for a local inflammatory response to infection alongside B cell maturation in the spleen, and upregulation of ccr9 genes in igt + B cells, T helper and cd8+ cells, and monocytes, consistent with the recruitment of immune cell populations to the gut to deal with Aeromonas infection. Overall, this study provides a new cell-resolved perspective of the immune actions of Atlantic salmon spleen, highlighting extensive heterogeneity hidden to bulk transcriptomics. We further provide a large catalogue of cell-specific marker genes that can be leveraged to further explore the function and structural organization of the salmonid immune system.
Collapse
Affiliation(s)
- Jianxuan Sun
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Midlothian, UK
| | - Rose Ruiz Daniels
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Midlothian, UK
| | - Adam Balic
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Midlothian, UK; Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria, Australia
| | | | - Håvard Bjørgen
- Unit of Anatomy, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Ross Dobie
- Centre for Inflammation Research, The Queen's Medical Research Institute, Edinburgh BioQuarter, University of Edinburgh, Edinburgh, UK
| | - Neil C Henderson
- Centre for Inflammation Research, The Queen's Medical Research Institute, Edinburgh BioQuarter, University of Edinburgh, Edinburgh, UK; MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, UK
| | - Erling Olaf Koppang
- Unit of Anatomy, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Samuel A M Martin
- Scottish Fish Immunology Research Centre, School of Biological Sciences, University of Aberdeen, Aberdeen, UK
| | | | - Richard S Taylor
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Midlothian, UK
| | - Daniel J Macqueen
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Midlothian, UK.
| |
Collapse
|
4
|
Borgonovo J, Allende-Castro C, Medinas DB, Cárdenas D, Cuevas MP, Hetz C, Concha ML. Immunohistochemical characterisation of the adult Nothobranchius furzeri intestine. Cell Tissue Res 2024; 395:21-38. [PMID: 38015266 DOI: 10.1007/s00441-023-03845-8] [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: 04/24/2023] [Accepted: 11/14/2023] [Indexed: 11/29/2023]
Abstract
Nothobranchius furzeri is emerging as an exciting vertebrate organism in the field of biomedicine, developmental biology and ecotoxicology research. Its short generation time, compressed lifespan and accelerated ageing make it a versatile model for longitudinal studies with high traceability. Although in recent years the use of this model has increased enormously, there is still little information on the anatomy, morphology and histology of its main organs. In this paper, we present a description of the digestive system of N. furzeri, with emphasis on the intestine. We note that the general architecture of the intestinal tissue is shared with other vertebrates, and includes a folding mucosa, an outer muscle layer and a myenteric plexus. By immunohistochemical analysis, we reveal that the mucosa harbours the same type of epithelial cells observed in mammals, including enterocytes, goblet cells and enteroendocrine cells, and that the myenteric neurons express neurotransmitters common to other species, such as serotonin, substance P and tyrosine hydroxylase. In addition, we detect the presence of a proliferative compartment at the base of the intestinal folds. The description of the normal intestinal morphology provided here constitutes a baseline information to contrast with tissue alterations in future lines of research assessing pathologies, ageing-related diseases or damage caused by toxic agents.
Collapse
Affiliation(s)
- Janina Borgonovo
- Integrative Biology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
- Biomedical Neuroscience Institute, Santiago, Chile
- Center for Geroscience, Brain Health and Metabolism, Santiago, Chile
| | - Camilo Allende-Castro
- Integrative Biology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
- Biomedical Neuroscience Institute, Santiago, Chile
- Center for Geroscience, Brain Health and Metabolism, Santiago, Chile
| | - Danilo B Medinas
- Biomedical Neuroscience Institute, Santiago, Chile
- Center for Geroscience, Brain Health and Metabolism, Santiago, Chile
- Cellular and Molecular Biology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Deyanira Cárdenas
- Integrative Biology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
- Center for Geroscience, Brain Health and Metabolism, Santiago, Chile
- Medical Technology School, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - María Paz Cuevas
- Integrative Biology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
- Center for Geroscience, Brain Health and Metabolism, Santiago, Chile
- Medical Technology School, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Claudio Hetz
- Biomedical Neuroscience Institute, Santiago, Chile
- Center for Geroscience, Brain Health and Metabolism, Santiago, Chile
- Cellular and Molecular Biology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
- Buck Institute for Research on Aging, Novato, CA, USA
| | - Miguel L Concha
- Integrative Biology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile.
- Biomedical Neuroscience Institute, Santiago, Chile.
- Center for Geroscience, Brain Health and Metabolism, Santiago, Chile.
| |
Collapse
|
5
|
Srirengaraj V, Razafindralambo HL, Rabetafika HN, Nguyen HT, Sun YZ. Synbiotic Agents and Their Active Components for Sustainable Aquaculture: Concepts, Action Mechanisms, and Applications. BIOLOGY 2023; 12:1498. [PMID: 38132324 PMCID: PMC10740583 DOI: 10.3390/biology12121498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 11/26/2023] [Accepted: 12/05/2023] [Indexed: 12/23/2023]
Abstract
Aquaculture is a fast-emerging food-producing sector in which fishery production plays an imperative socio-economic role, providing ample resources and tremendous potential worldwide. However, aquatic animals are exposed to the deterioration of the ecological environment and infection outbreaks, which represent significant issues nowadays. One of the reasons for these threats is the excessive use of antibiotics and synthetic drugs that have harmful impacts on the aquatic atmosphere. It is not surprising that functional and nature-based feed ingredients such as probiotics, prebiotics, postbiotics, and synbiotics have been developed as natural alternatives to sustain a healthy microbial environment in aquaculture. These functional feed additives possess several beneficial characteristics, including gut microbiota modulation, immune response reinforcement, resistance to pathogenic organisms, improved growth performance, and enhanced feed utilization in aquatic animals. Nevertheless, their mechanisms in modulating the immune system and gut microbiota in aquatic animals are largely unclear. This review discusses basic and current research advancements to fill research gaps and promote effective and healthy aquaculture production.
Collapse
Affiliation(s)
| | - Hary L. Razafindralambo
- ProBioLab, 5004 Namur, Belgium;
- BioEcoAgro Joint Research Unit, TERRA Teaching and Research Centre, Sustainable Management of Bio-Agressors & Microbial Technologies, Gembloux Agro-Bio Tech—Université de Liège, 5030 Gembloux, Belgium
| | | | - Huu-Thanh Nguyen
- Department of Biotechnology, An Giang University, Long Xuyen City 90000, Vietnam;
| | - Yun-Zhang Sun
- Fisheries College, Jimei University, Xiamen 361021, China;
| |
Collapse
|
6
|
Zhao X, Liu Y, Xie J, Zhang L, Zhu Q, Su L, Guo C, Li H, Wang G, Zhang W, Cheng Y, Wu N, Xia XQ. The manipulation of cell suspensions from zebrafish intestinal mucosa contributes to understanding enteritis. Front Immunol 2023; 14:1193977. [PMID: 37251394 PMCID: PMC10213505 DOI: 10.3389/fimmu.2023.1193977] [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: 03/26/2023] [Accepted: 04/24/2023] [Indexed: 05/31/2023] Open
Abstract
Background Although zebrafish are commonly used to study intestinal mucosal immunity, no dedicated procedure for isolating immune cells from zebrafish intestines is currently available. A speedy and simple operating approach for preparing cell suspension from mucosa has been devised to better understanding of intestinal cellular immunity in zebrafish. Methods and results The mucosal villi were separated away from the muscle layer by repeated blows. The complete deprivation of mucosa was done and evidenced by HE and qPCR results. Higher expression of both innate (mpeg1, mpx, and lck) and adaptive immune genes (zap70, blnk, foxp3a, and foxp3b) was revealed compared to cells obtained by typical mesh rubbing. The cytometric results also revealed that the tested operation group had a higher concentration and viability. Further, fluorescent-labelled immune cells from 3mo Tg(lyz:DsRED2), Tg(mpeg1:EGFP), Tg(Rag2:DsRED), and Tg(lck:EGFP), were isolated and evaluated for the proportion, and immune cells' type could be inferred from the expression of marker genes. The transcriptomic data demonstrated that the intestinal immune cell suspension made using the new technique was enriched in immune-related genes and pathways, including il17a/f, il22, cd59, and zap70, as well as pattern recognition receptor signaling and cytokine-cytokine receptor interaction. In addition, the low expression of DEG for the adherent and close junctions indicated less muscular contamination. Also, lower expression of gel-forming mucus-associated genes in the mucosal cell suspension was consistent with the current less viscous cell suspension. To apply and validate the developed manipulation, enteritis was induced by soybean meal diet, and immune cell suspensions were analyzed by flow cytometry and qPCR. The finding that in enteritis samples, there was inflammatory increase of neutrophils and macrophages, was in line with upregulated cytokines (il8 and il10) and cell markers (mpeg1 and mpx). Conclusion As a result, the current work created a realistic technique for studying intestinal immune cells in zebrafish. The immune cells acquired may aid in further research and knowledge of intestinal illness at the cellular level.
Collapse
Affiliation(s)
- Xuyang Zhao
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Fisheries and Life Science, Dalian Ocean University, Dalian, China
| | - Yuhang Liu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Fisheries and Life Science, Dalian Ocean University, Dalian, China
| | - Jiayuan Xie
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Lei Zhang
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Qingsong Zhu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Fisheries and Life Science, Dalian Ocean University, Dalian, China
| | - Lian Su
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Cheng Guo
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Heng Li
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Guangxin Wang
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Wanting Zhang
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Yingyin Cheng
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Nan Wu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Xiao-Qin Xia
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| |
Collapse
|
7
|
Lee PT, Yamamoto FY, Low CF, Loh JY, Chong CM. Gut Immune System and the Implications of Oral-Administered Immunoprophylaxis in Finfish Aquaculture. Front Immunol 2022; 12:773193. [PMID: 34975860 PMCID: PMC8716388 DOI: 10.3389/fimmu.2021.773193] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 11/23/2021] [Indexed: 12/13/2022] Open
Abstract
The gastrointestinal immune system plays an important role in immune homeostasis regulation. It regulates the symbiotic host-microbiome interactions by training and developing the host's innate and adaptive immunity. This interaction plays a vital role in host defence mechanisms and at the same time, balancing the endogenous perturbations of the host immune homeostasis. The fish gastrointestinal immune system is armed with intricate diffused gut-associated lymphoid tissues (GALTs) that establish tolerance toward the enormous commensal gut microbiome while preserving immune responses against the intrusion of enteric pathogens. A comprehensive understanding of the intestinal immune system is a prerequisite for developing an oral vaccine and immunostimulants in aquaculture, particularly in cultured fish species. In this review, we outline the remarkable features of gut immunity and the essential components of gut-associated lymphoid tissue. The mechanistic principles underlying the antigen absorption and uptake through the intestinal epithelial, and the subsequent immune activation through a series of molecular events are reviewed. The emphasis is on the significance of gut immunity in oral administration of immunoprophylactics, and the different potential adjuvants that circumvent intestinal immune tolerance. Comprehension of the intestinal immune system is pivotal for developing effective fish vaccines that can be delivered orally, which is less labour-intensive and could improve fish health and facilitate disease management in the aquaculture industry.
Collapse
Affiliation(s)
- Po-Tsang Lee
- Department of Aquaculture, National Taiwan Ocean University, Keelung, Taiwan
| | - Fernando Y Yamamoto
- Thad Cochran National Warmwater Aquaculture Center, Mississippi Agriculture and Forestry Experiment Station, Mississippi State University, Stoneville, MS, United States
| | - Chen-Fei Low
- Institute of Systems Biology, Universiti Kebangsaan Malaysia, Bangi, Malaysia
| | - Jiun-Yan Loh
- Centre of Research for Advanced Aquaculture (CORAA), UCSI University, Cheras, Malaysia
| | - Chou-Min Chong
- Aquatic Animal Health and Therapeutics Laboratory (AquaHealth), Institute of Bioscience, Universiti Putra Malaysia, Serdang, Malaysia
| |
Collapse
|
8
|
Park Y, Zhang Q, Fernandes JMO, Wiegertjes GF, Kiron V. Macrophage Heterogeneity in the Intestinal Cells of Salmon: Hints From Transcriptomic and Imaging Data. Front Immunol 2021; 12:798156. [PMID: 35003123 PMCID: PMC8733388 DOI: 10.3389/fimmu.2021.798156] [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: 10/19/2021] [Accepted: 11/24/2021] [Indexed: 11/13/2022] Open
Abstract
The intestine has many types of cells that are present mostly in the epithelium and lamina propria. The importance of the intestinal cells for the mammalian mucosal immune system is well-established. However, there is no in-depth information about many of the intestinal cells in teleosts. In our previous study, we reported that adherent intestinal cells (AIC) predominantly express macrophage-related genes. To gather further evidence that AIC include macrophage-like cells, we compared their phagocytic activity and morphology with those of adherent head kidney cells (AKC), previously characterized as macrophage-like cells. We also compared equally abundant as well as differentially expressed mRNAs and miRNAs between AIC and AKC. AIC had lower phagocytic activity and were larger and more circular than macrophage-like AKC. RNA-Seq data revealed that there were 18309 mRNAs, with 59 miRNAs that were equally abundant between AIC and AKC. Integrative analysis of the mRNA and miRNA transcriptomes revealed macrophage heterogeneity in both AIC and AKC. In addition, analysis of AIC and AKC transcriptomes revealed functional characteristics of mucosal and systemic macrophages. Five pairs with significant negative correlations between miRNA and mRNAs were linked to macrophages and epithelial cells and their interaction could be pointing to macrophage activation and differentiation. The potential macrophage markers suggested in this study should be investigated under different immune conditions to understand the exact macrophage phenotypes.
Collapse
Affiliation(s)
- Youngjin Park
- Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
| | - Qirui Zhang
- Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
| | | | - Geert F. Wiegertjes
- Aquaculture and Fisheries Group, Wageningen University & Research, Wageningen, Netherlands
| | - Viswanath Kiron
- Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
| |
Collapse
|