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Quiroga J, Cortes B, Sarmiento J, Morán G, Henríquez C. Characterization of extracellular trap production and release by equine neutrophils in response to different stimuli. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2024; 155:105151. [PMID: 38423491 DOI: 10.1016/j.dci.2024.105151] [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: 01/04/2024] [Revised: 01/31/2024] [Accepted: 02/19/2024] [Indexed: 03/02/2024]
Abstract
This study explores Neutrophil Extracellular Trap (NET) formation in equine neutrophils, which is crucial for eliminating infections and is implicated in various equine inflammatory diseases. We investigated the molecular pathways involved in NET release by equine neutrophils in response to stimuli. We use PMA, A23187, LPS, PAF, OZ, and cytokines, observing NET release in response to PMA, PAF, and A23187. In contrast, LPS, OZ, and the cytokines tested did not induce DNA release or did not consistently induce citrullination of histone 4. Peptidyl-arginine deiminase inhibition completely halted NET release, while NADPH oxidase and mitochondrial reactive oxygen species only played a role in PMA-induced NETs. Neutrophil elastase inhibition modestly affected PAF-induced NET liberation but not in PMA or A23187-induced NET, while myeloperoxidase did not contribute to NET release. We expect to provide a foundation for future investigations into the role of NETs in equine health and disease and the search for potential therapeutic targets.
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Affiliation(s)
- John Quiroga
- Instituto de Farmacología y Morfofisiología, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Chile
| | - Bayron Cortes
- Instituto de Farmacología y Morfofisiología, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Chile
| | - José Sarmiento
- Instituto de Fisiología, Facultad de Medicina, Universidad Austral de Chile, Chile
| | - Gabriel Morán
- Instituto de Farmacología y Morfofisiología, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Chile
| | - Claudio Henríquez
- Instituto de Farmacología y Morfofisiología, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Chile.
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2
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Vajdi M, Karimi A, Hassanizadeh S, Farhangi MA, Bagherniya M, Askari G, Roufogalis BD, Davies NM, Sahebkar A. Effect of polyphenols against complications of COVID-19: current evidence and potential efficacy. Pharmacol Rep 2024; 76:307-327. [PMID: 38498260 DOI: 10.1007/s43440-024-00585-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Revised: 03/01/2024] [Accepted: 03/03/2024] [Indexed: 03/20/2024]
Abstract
The COVID-19 pandemic that started in 2019 and resulted in significant morbidity and mortality continues to be a significant global health challenge, characterized by inflammation, oxidative stress, and immune system dysfunction.. Developing therapies for preventing or treating COVID-19 remains an important goal for pharmacology and drug development research. Polyphenols are effective against various viral infections and can be extracted and isolated from plants without losing their therapeutic potential. Researchers have developed methods for separating and isolating polyphenols from complex matrices. Polyphenols are effective in treating common viral infections, including COVID-19, and can also boost immunity. Polyphenolic-based antiviral medications can mitigate SARS-CoV-2 enzymes vital to virus replication and infection. Individual polyphenolic triterpenoids, flavonoids, anthraquinonoids, and tannins may also inhibit the SARS-CoV-2 protease. Polyphenol pharmacophore structures identified to date can explain their action and lead to the design of novel anti-COVID-19 compounds. Polyphenol-containing mixtures offer the advantages of a well-recognized safety profile with few known severe side effects. However, studies to date are limited, and further animal studies and randomized controlled trials are needed in future studies. The purpose of this study was to review and present the latest findings on the therapeutic impact of plant-derived polyphenols on COVID-19 infection and its complications. Exploring alternative approaches to traditional therapies could aid in developing novel drugs and remedies against coronavirus infection.
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Affiliation(s)
- Mahdi Vajdi
- Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Arash Karimi
- Traditional Medicine and Hydrotherapy Research Center, Ardabil University of Medical Sciences, Ardabil, Iran
| | - Shirin Hassanizadeh
- Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mahdieh Abbasalizad Farhangi
- Department of Community Nutrition, Faculty of Nutrition and Food Science, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Bagherniya
- Department of Community Nutrition, Food Security Research Center, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran
- Anesthesia and Critical Care Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Gholamreza Askari
- Department of Community Nutrition, Food Security Research Center, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran
- Anesthesia and Critical Care Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Basil D Roufogalis
- Discipline of Pharmacology, School of Medical Sciences, University of Sydney, Sydney, NSW, Australia
- NICM Health Research Institute, Western Sydney University, Penrith, NSW, Australia
| | - Neal M Davies
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, T6G 2P5, Canada
| | - Amirhossein Sahebkar
- Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran.
- Applied Biomedical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
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3
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Mou CY, Zhang L, Zhao H, Huang ZP, Duan YL, Zhao ZM, Ke HY, Du J, Li Q, Zhou J. Single-nuclei RNA-seq reveals skin cell responses to Aeromonas hydrophila infection in Chinese longsnout catfish Leiocassis longirostris. Front Immunol 2023; 14:1271466. [PMID: 37908355 PMCID: PMC10613986 DOI: 10.3389/fimmu.2023.1271466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 09/25/2023] [Indexed: 11/02/2023] Open
Abstract
As the primary natural barrier that protects against adverse environmental conditions, the skin plays a crucial role in the innate immune response of fish, particularly in relation to bacterial infections. However, due to the diverse functionality and intricate anatomical and cellular composition of the skin, deciphering the immune response of the host is a challenging task. In this study, single nuclei RNA-sequencing (snRNA-seq) was performed on skin biopsies obtained from Chinese longsnout catfish (Leiocassis longirostris), comparing Aeromonas hydrophila-infected subjects to healthy control subjects. A total of 19,581 single nuclei cells were sequenced using 10x Genomics (10,400 in the control group and 9,181 in the treated group). Based on expressed unique transcriptional profiles, 33 cell clusters were identified and classified into 12 cell types including keratinocyte (KC), fibroblast (FB), endothelial cells (EC), secretory cells (SC), immune cells, smooth muscle cells (SMC), and other cells such as pericyte (PC), brush cell (BC), red blood cell (RBC), neuroendocrine cell (NDC), neuron cells (NC), and melanocyte (MC). Among these, three clusters of KCs, namely, KC1, KC2, and KC5 exhibited significant expansion after A. hydrophila infection. Analysis of pathway enrichment revealed that KC1 was primarily involved in environmental signal transduction, KC2 was primarily involved in endocrine function, and KC5 was primarily involved in metabolism. Finally, our findings suggest that neutrophils may play a crucial role in combating A. hydrophila infections. In summary, this study not only provides the first detailed comprehensive map of all cell types present in the skin of teleost fish but also sheds light on the immune response mechanism of the skin following A. hydrophila infection in Chinese longsnout catfish.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Qiang Li
- Fisheries Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, Sichuan, China
| | - Jian Zhou
- Fisheries Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, Sichuan, China
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Han Y, Zhang Q, Chen L, Zhao J, Yang D. In vitro study of deltamethrin-induced extracellular traps in hemocytes of Ruditapes philippinarum. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 256:114909. [PMID: 37062260 DOI: 10.1016/j.ecoenv.2023.114909] [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: 01/11/2023] [Revised: 04/02/2023] [Accepted: 04/09/2023] [Indexed: 06/19/2023]
Abstract
Deltamethrin (DLM), a broad-spectrum pesticide, has been proven to have toxic effects on aquatic organisms. Here, we detected the formation of extracellular traps (ETosis) formation in Manila clam (Ruditapes philippinarum) hemocytes stimulated by three concentrations of DLM (0.01, 0.1 and 1 μg/mL) in vitro, and explored the underlying mechanisms induced by this pesticide. Extracellular DNA structure observation and quantitative results indicated that DLM exposure could obviously induce hemocytes ETosis, especially under high concentration of DLM induction. Moreover, DLM increased the levels of myeloperoxidase (MPO) and reactive oxygen species (ROS) in a dose-dependent manner, and enhanced the mRNA expression of several ROS-related genes. DPI (NADPH oxidase inhibitor) and ABAH (MPO inhibitor) could substantially inhibit DLM-induced extracellular traps (ETs), suggesting that the induced ETs release was caused by the induction of the ROS burst and MPO production. In addition, three concentrations of DLM-induced ETs were also accompanied by mitochondrial dysfunction, such as increasing the production of mitochondrial ROS, leading to a decrease in mitochondrial membrane potential (MMP) and activation of mitochondrial permeability transition pore (MPTP). Taken together, these results will shed new light on the immunotoxicity of DLM in clams and perhaps lays the foundation for health assessment in bivalves.
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Affiliation(s)
- Yijing Han
- School of Agriculture, Ludong University, Yantai, Shandong 264025, PR China
| | - Qianqian Zhang
- Muping Coastal Environment Research Station, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, Shandong 264003, PR China; Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, Shandong 264003, PR China
| | - Lizhu Chen
- Shandong Marine Resource and Environment Research Institute, Yantai, Shandong 264006, PR China
| | - Jianmin Zhao
- Muping Coastal Environment Research Station, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, Shandong 264003, PR China; Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, Shandong 264003, PR China
| | - Dinglong Yang
- Muping Coastal Environment Research Station, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, Shandong 264003, PR China; Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, Shandong 264003, PR China.
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Martinez V, Dettleff P, Zamorano P, Galarce N, Borie C, Naish K. Host-pathogen interaction involving cytoskeleton changes as well as non-coding regulation as primary mechanisms for SRS resistance in Atlantic salmon. FISH & SHELLFISH IMMUNOLOGY 2023; 136:108711. [PMID: 37004895 DOI: 10.1016/j.fsi.2023.108711] [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: 11/26/2021] [Revised: 03/22/2023] [Accepted: 03/25/2023] [Indexed: 06/19/2023]
Abstract
The salmonid rickettsial syndrome (SRS) is a systemic bacterial infection caused by Piscirickettsia salmonis that generates significant economic losses in Atlantic salmon (Salmo salar) aquaculture. Despite this disease's relevance, the mechanisms involved in resistance against P. salmonis infection are not entirely understood. Thus, we aimed at studying the pathways explaining SRS resistance using different approaches. First, we determined the heritability using pedigree data from a challenge test. Secondly, a genome-wide association analysis was performed following a complete transcriptomic profile of fish from genetically susceptible and resistant families within the challenge infection with P. salmonis. We found differentially expressed transcripts related to immune response, pathogen recognition, and several new pathways related to extracellular matrix remodelling and intracellular invasion. The resistant background showed a constrained inflammatory response, mediated by the Arp2/3 complex actin cytoskeleton remodelling polymerization pathway, probably leading to bacterial clearance. A series of biomarkers of SRS resistance, such as the beta-enolase (ENO-β), Tubulin G1 (TUBG1), Plasmin (PLG) and ARP2/3 Complex Subunit 4 (ARPC4) genes showed consistent overexpression in resistant individuals, showing promise as biomarkers for SRS resistance. All these results together with the differential expression of several long non-coding RNAs show the complexity of the host-pathogen interaction of S. salar and P. salmonis. These results provide valuable information on new models describing host-pathogen interaction and its role in SRS resistance.
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Affiliation(s)
- Victor Martinez
- FAVET-INBIOGEN, Faculty of Veterinary Sciences, University of Chile, Avda. Santa Rosa, 11735, Santiago, Chile.
| | - Phillip Dettleff
- FAVET-INBIOGEN, Faculty of Veterinary Sciences, University of Chile, Avda. Santa Rosa, 11735, Santiago, Chile
| | - Pedro Zamorano
- Cell and Molecular Biology-Genetics Unit, University of Antofagasta, Antofagasta, Chile
| | - Nicolás Galarce
- Escuela de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago, 8370146, Chile
| | - Consuelo Borie
- Escuela de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago, 8370146, Chile
| | - Kerry Naish
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, United States
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Van AP, Bron JE, Desbois AP. Antimicrobial action of chromatin extracellular traps released by neutrophils of rainbow trout, Oncorhynchus mykiss (Walbaum, 1792). FISH & SHELLFISH IMMUNOLOGY 2023; 135:108657. [PMID: 36868536 DOI: 10.1016/j.fsi.2023.108657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 02/14/2023] [Accepted: 02/28/2023] [Indexed: 05/19/2023]
Affiliation(s)
- Andre P Van
- Institute of Aquaculture, Faculty of Natural Sciences, University of Stirling, Stirling, FK9 4LA, United Kingdom
| | - James E Bron
- Institute of Aquaculture, Faculty of Natural Sciences, University of Stirling, Stirling, FK9 4LA, United Kingdom
| | - Andrew P Desbois
- Institute of Aquaculture, Faculty of Natural Sciences, University of Stirling, Stirling, FK9 4LA, United Kingdom.
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Valenzuela-Aviles P, Torrealba D, Figueroa C, Mercado L, Dixon B, Conejeros P, Gallardo-Matus J. Why vaccines fail against Piscirickettsiosis in farmed salmon and trout and how to avoid it: A review. Front Immunol 2022; 13:1019404. [PMID: 36466828 PMCID: PMC9714679 DOI: 10.3389/fimmu.2022.1019404] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 10/24/2022] [Indexed: 09/28/2023] Open
Abstract
Piscirickettsiosis is the most severe, persistent, and damaging disease that has affected the Chilean salmon industry since its origins in the 1980s. As a preventive strategy for this disease, different vaccines have been developed and used over the last 30 years. However, vaccinated salmon and trout frequently die in the sea cages and the use of antibiotics is still high demonstrating the low efficiency of the available vaccines. The reasons why the vaccines fail so often are still debated, but it could involve different extrinsic and intrinsic factors. Among the extrinsic factors, mainly associated with chronic stress, we can distinguish: 1) biotic including coinfection with sea lice, sealions attacks or harmful algal blooms; 2) abiotic including low oxygen or high temperature; and 3) farm-management factors including overcrowding or chemical delousing treatments. Among the intrinsic factors, we can distinguish: 1) fish-related factors including host's genetic variability (species, population and individual), sex or age; 2) pathogen-related factors including their variability and ability to evade host immune responses; and 3) vaccine-related factors including low immunogenicity and poor matches with the circulating pathogen strain. Based on the available evidence, in order to improve the development and the efficacy of vaccines against P. salmonis we recommend: a) Do not perform efficacy evaluations by intraperitoneal injection of pathogens because they generate an artificial protective immune response, instead cohabitation or immersion challenges must be used; b) Evaluate the diversity of pathogen strains in the field and ensure a good antigenic match with the vaccines; c) Investigate whether host genetic diversity could be improved, e.g. through selection, in favor of better and longer responses to vaccination; d) To reduce the stressful effects at the cage level, controlling the co-infection of pathogens and avoiding fish overcrowding. To date, we do not know the immunological mechanisms by which the vaccines against P. salmonis may or may not generate protection. More studies are required to identify what type of response, cellular or molecular, is required to develop effective vaccines.
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Affiliation(s)
- Paula Valenzuela-Aviles
- Laboratorio de Genética y Genómica Aplicada, Escuela de Ciencias del Mar, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Débora Torrealba
- Laboratorio de Genética y Genómica Aplicada, Escuela de Ciencias del Mar, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Carolina Figueroa
- Laboratorio de Genética y Genómica Aplicada, Escuela de Ciencias del Mar, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Luis Mercado
- Grupo de Marcadores Inmunológicos en Organismos Acuáticos, Pontificia Universidad Católica de Valparaíso, Instituto de Biología, Valparaíso, Chile
| | - Brian Dixon
- Department of Biology, Faculty of Science, University of Waterloo, Waterloo, Canada
| | - Pablo Conejeros
- Centro de Investigación y Gestión de Recursos Naturales (CIGREN), Facultad de Ciencias, Instituto de Biología, Universidad de Valparaíso, Valparaíso, Chile
| | - José Gallardo-Matus
- Laboratorio de Genética y Genómica Aplicada, Escuela de Ciencias del Mar, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
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Albaladejo-Riad N, Cuesta A, Esteban MÁ. Induction and characterization of extracellular traps by gilthead seabream (Sparus aurata L.) head-kidney leucocytes. FISH & SHELLFISH IMMUNOLOGY 2022; 130:582-590. [PMID: 36152801 DOI: 10.1016/j.fsi.2022.09.045] [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: 08/18/2022] [Revised: 09/15/2022] [Accepted: 09/17/2022] [Indexed: 06/16/2023]
Abstract
The aim of this study was the induction and characterization of extracellular traps (ETs) produced by gilthead seabream (Sparus aurata L.) head-kidney leucocytes. The cells were incubated several times (10, 30, 60, 120, and 180 min) with different concentrations of the stimulants diluted in RPMI-1640 culture medium: RPMI-1640 (control), β-glucan from Saccharomyces cerevisiae (BG, 0-400 μg mL-1), lipopolysaccharide from Escherichia coli (LPS, 0-10 μg mL-1), calcium ionophore A23187 (CaI, 0-5 μg mL-1), Phorbol 12-myristate 13-acetate (PMA, 0-1000 ng mL-1) and polyinosinic-polycytidylic acid sodium salt (Poly I:C, 0-200 μg mL-1). BG, LPS and CaI exerted only weak stimulatory activity, while PMA and poly I:C exerted a potent one. After stimulation of the leucocytes, ETs structures were quantified and visualised through staining of the chromatin with nucleic acid-specific dyes and immunocytochemical probing of characteristic proteins expected to decorate the structure. ETs structures had DNA and myeloperoxidase. The ETs morphology was studied by light and scanning electron microscopy. These data confirm that seabream leucocytes form ETs with different morphological properties, depending on the used stimulant. These results will be the basis for new studies to analyse the implication of this mechanism in fish immunity. All this new knowledge will have its application in fish farms when we learn to manipulate the innate immune response in order to mitigate microbial infections.
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Affiliation(s)
- Nora Albaladejo-Riad
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, 30100, Murcia, Spain
| | - Alberto Cuesta
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, 30100, Murcia, Spain
| | - M Ángeles Esteban
- Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, 30100, Murcia, Spain.
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Álvarez de Haro N, Van AP, Robb CT, Rossi AG, Desbois AP. Release of chromatin extracellular traps by phagocytes of Atlantic salmon, Salmo salar (Linnaeus, 1758). FISH & SHELLFISH IMMUNOLOGY 2021; 119:209-219. [PMID: 34438058 PMCID: PMC8653909 DOI: 10.1016/j.fsi.2021.08.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 08/18/2021] [Accepted: 08/22/2021] [Indexed: 05/05/2023]
Abstract
Neutrophils release chromatin extracellular traps (ETs) as part of the fish innate immune response to counter the threats posed by microbial pathogens. However, relatively little attention has been paid to this phenomenon in many commercially farmed species, despite the importance of understanding host-pathogen interactions and the potential to influence ET release to reduce disease outbreaks. The aim of this present study was to investigate the release of ETs by Atlantic salmon (Salmo salar L.) immune cells. Extracellular structures resembling ETs of different morphology were observed by fluorescence microscopy in neutrophil suspensions in vitro, as these structures stained positively with Sytox Green and were digestible with DNase I. Immunofluorescence studies confirmed the ET structures to be decorated with histones H1 and H2A and neutrophil elastase, which are characteristic for ETs in mammals and other organisms. Although the ETs were released spontaneously, release in neutrophil suspensions was stimulated most significantly with 5 μg/ml calcium ionophore (CaI) for 1 h, whilst the fish pathogenic bacterium Aeromonas salmonicida (isolates 30411 and Hooke) also exerted a stimulatory effect. Microscopic observations revealed bacteria in association with ETs, and fewer bacterial colonies of A. salmonicida Hooke were recovered at 3 h after co-incubation with neutrophils that had been induced to release ETs. Interestingly, spontaneous release of ETs was inversely associated with fish mass (p < 0.05), a surrogate for age. Moreover, suspensions enriched for macrophages and stimulated with 5 μg/ml CaI released ET-like structures that occasionally led to the formation of large clumps of cells. A deeper understanding for the roles and functions of ETs within innate immunity of fish hosts, and their interaction with microbial pathogens, may open new avenues towards protecting cultured stocks against infectious diseases.
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Affiliation(s)
- Neila Álvarez de Haro
- Institute of Aquaculture, Faculty of Natural Sciences, University of Stirling, Stirling, FK9 4LA, United Kingdom
| | - Andre P Van
- Institute of Aquaculture, Faculty of Natural Sciences, University of Stirling, Stirling, FK9 4LA, United Kingdom
| | - Calum T Robb
- University of Edinburgh, Centre for Inflammation Research, Queen's Medical Research Institute, Edinburgh, EH16 4TJ, United Kingdom
| | - Adriano G Rossi
- University of Edinburgh, Centre for Inflammation Research, Queen's Medical Research Institute, Edinburgh, EH16 4TJ, United Kingdom
| | - Andrew P Desbois
- Institute of Aquaculture, Faculty of Natural Sciences, University of Stirling, Stirling, FK9 4LA, United Kingdom.
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10
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Cortés HD, Gómez FA, Marshall SH. The Phagosome-Lysosome Fusion Is the Target of a Purified Quillaja saponin Extract (PQSE) in Reducing Infection of Fish Macrophages by the Bacterial Pathogen Piscirickettsia salmonis. Antibiotics (Basel) 2021; 10:antibiotics10070847. [PMID: 34356768 PMCID: PMC8300623 DOI: 10.3390/antibiotics10070847] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/26/2021] [Accepted: 06/28/2021] [Indexed: 12/20/2022] Open
Abstract
Piscirickettsia salmonis, the etiological agent of Piscirickettsiosis, is a Gram-negative and facultative intracellular pathogen that has affected the Chilean salmon industry since 1989. The bacterium is highly aggressive and can survive and replicate within fish macrophages using the Dot/Icm secretion system to evade the host’s immune response and spread systemically. To date, no efficient control measures have been developed for this disease; therefore, the producers use large amounts of antibiotics to control this pathogen. In this frame, this work has focused on evaluating the use of saponins from Quillaja saponaria as a new alternative to control the Piscirickettsiosis. It has been previously reported that purified extract of Q. saponaria (PQSE) displays both antimicrobial activity against pathogenic bacteria and viruses and adjuvant properties. Our results show that PQSE does not present antimicrobial activity against P. salmonis, although it reduces P. salmonis infection in an in vitro model, promoting the phagosome–lysosome fusion. Additionally, we demonstrate that PQSE modulates the expression of IL-12 and IL-10 in infected cells, promoting the immune response against the pathogen and reducing the expression of pathogen virulence genes. These results together strongly argue for specific anti-invasion and anti-intracellular replication effects induced by the PQSE in macrophages.
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