1
|
Piva MM, Schwertz CI, Henker LC, Bianchi RM, Kemper RT, de Almeida BA, Nagae RY, Michaelsen TR, Pavarini SP. Non-ambulatory pigs in two Brazilian growing-finishing farms: a clinic, etiological and pathological perspective on 76 cases. Porcine Health Manag 2022; 8:36. [PMID: 35948945 PMCID: PMC9364575 DOI: 10.1186/s40813-022-00279-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 08/01/2022] [Indexed: 12/04/2022] Open
Abstract
Background Non-ambulatory pigs, colloquially known as downers or downed pigs, are animals presented with limited to no mobility, usually as a result of pre-existing neurologic or musculoskeletal conditions. Impaired ambulation is a major cause of euthanasia in pigs, leading to economic losses and animal welfare concerns. Additionally, reaching the underlying diagnosis of impaired ambulation in pigs is commonly a challenging task for swine practitioners. The aim of this necropsy-based study was to report the clinical, etiological, and pathological findings of 76 non-ambulatory grower-finisher pigs, and to correlate tail-biting lesions with the causes of death/reason for euthanasia in non-ambulatory pigs. Necropsies of downed pigs were performed during on-site visits to two pig farms in southern Brazil. Results The diagnosis of the conditions was based on the clinical, macroscopic, histopathological, bacteriological, immunohistochemical, and molecular findings. The diseases diagnosed in non-ambulatory pigs in this study were suppurative arthritis (29/76), suppurative spondylitis (10/76), PVC-2 associated diseases (8/76), bone fracture (7/76), non-suppurative meningoencephalomyelitis (4/76), suppurative meningoencephalitis (6/76), fibrocartilaginous thromboembolism (3/76), epiphysiolysis (3/76), ascending bacterial myelitis (3/76), and other conditions (3/76). The frequency of suppurative arthritis, suppurative spondylitis, and ascending bacterial myelitis/meningitis was higher in pigs with tail biting lesions than controls (P < 0.001). Conclusions Non-ambulatory pigs were observed during the entire rearing period, however, the occurrence of non-ambulatory pigs increased in animals aged ≥ 150 days. Infectious diseases were the most common cause of downed pigs, mainly associated with chronic bacterial infections. Tail biting lesions were an important predisposing factor to suppurative arthritis, suppurative spondylitis, and ascending bacterial myelitis/meningitis.
Collapse
Affiliation(s)
- Manoela Marchezan Piva
- Departament of Veterinary Pathology, Faculty of Veterinary Medicine, Federal University of Rio Grande Do Sul - UFRGS, 9090 Av. Bento Gonçalves, Porto Alegre, Rio Grande Do Sul, 91540-000, Brazil.
| | - Claiton I Schwertz
- Departament of Veterinary Pathology, Faculty of Veterinary Medicine, Federal University of Rio Grande Do Sul - UFRGS, 9090 Av. Bento Gonçalves, Porto Alegre, Rio Grande Do Sul, 91540-000, Brazil
| | - Luan Cleber Henker
- Departament of Veterinary Pathology, Faculty of Veterinary Medicine, Federal University of Rio Grande Do Sul - UFRGS, 9090 Av. Bento Gonçalves, Porto Alegre, Rio Grande Do Sul, 91540-000, Brazil
| | - Ronaldo Michel Bianchi
- Departament of Veterinary Pathology, Faculty of Veterinary Medicine, Federal University of Rio Grande Do Sul - UFRGS, 9090 Av. Bento Gonçalves, Porto Alegre, Rio Grande Do Sul, 91540-000, Brazil
| | - Regina Tose Kemper
- Departament of Veterinary Pathology, Faculty of Veterinary Medicine, Federal University of Rio Grande Do Sul - UFRGS, 9090 Av. Bento Gonçalves, Porto Alegre, Rio Grande Do Sul, 91540-000, Brazil
| | - Bruno Albuquerque de Almeida
- Departament of Veterinary Pathology, Faculty of Veterinary Medicine, Federal University of Rio Grande Do Sul - UFRGS, 9090 Av. Bento Gonçalves, Porto Alegre, Rio Grande Do Sul, 91540-000, Brazil
| | - Ricardo Yuiti Nagae
- Animal Health Laboratory, Seara Alimentos LTDA, 155 Av. Paludo, Industrial, Seara, Santa Catarina, 89770-000, Brazil
| | - Taís Regina Michaelsen
- Animal Health Laboratory, Seara Alimentos LTDA, 155 Av. Paludo, Industrial, Seara, Santa Catarina, 89770-000, Brazil
| | - Saulo Petinatti Pavarini
- Departament of Veterinary Pathology, Faculty of Veterinary Medicine, Federal University of Rio Grande Do Sul - UFRGS, 9090 Av. Bento Gonçalves, Porto Alegre, Rio Grande Do Sul, 91540-000, Brazil
| |
Collapse
|
2
|
A Triple Gene-Deleted Pseudorabies Virus-Vectored Subunit PCV2b and CSFV Vaccine Protects Pigs against PCV2b Challenge and Induces Serum Neutralizing Antibody Response against CSFV. Vaccines (Basel) 2022; 10:vaccines10020305. [PMID: 35214763 PMCID: PMC8878206 DOI: 10.3390/vaccines10020305] [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: 12/23/2021] [Revised: 02/09/2022] [Accepted: 02/12/2022] [Indexed: 02/04/2023] Open
Abstract
Porcine circovirus type 2 (PCV2) is endemic worldwide. PCV2 causes immunosuppressive infection. Co-infection of pigs with other swine viruses, such as pseudorabies virus (PRV) and classical swine fever virus (CSFV), have fatal outcomes, causing the swine industry significant economic losses in many if not all pig-producing countries. Currently available inactivated/modified-live/vectored vaccines against PCV2/CSFV/PRV have safety and efficacy limitations. To address these shortcomings, we have constructed a triple gene (thymidine kinase, glycoprotein E [gE], and gG)-deleted (PRVtmv) vaccine vector expressing chimeric PCV2b-capsid, CSFV-E2, and chimeric Erns-fused with bovine granulocytic monocyte-colony stimulating factor (Erns-GM-CSF), designated as PRVtmv+, a trivalent vaccine. Here we compared this vaccine’s immunogenicity and protective efficacy in pigs against wild-type PCV2b challenge with that of the inactivated Zoetis Fostera Gold PCV commercial vaccine. The live PRVtmv+ prototype trivalent subunit vaccine is safe and highly attenuated in pigs. Based on PCV2b-specific neutralizing antibody titers, viremia, viral load in lymphoid tissues, fecal-virus shedding, and leukocyte/lymphocyte count, the PRVtmv+ yielded better protection for vaccinated pigs than the commercial vaccine after the PCV2b challenge. Additionally, the PRVtmv+ vaccinated pigs generated low to moderate levels of CSFV-specific neutralizing antibodies.
Collapse
|
3
|
Alex CE, Fahsbender E, Altan E, Bildfell R, Wolff P, Jin L, Black W, Jackson K, Woods L, Munk B, Tse T, Delwart E, Pesavento PA. Viruses in unexplained encephalitis cases in American black bears (Ursus americanus). PLoS One 2020; 15:e0244056. [PMID: 33332429 PMCID: PMC7745964 DOI: 10.1371/journal.pone.0244056] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 12/02/2020] [Indexed: 11/29/2022] Open
Abstract
Viral infections were investigated in American black bears (Ursus americanus) from Nevada and northern California with and without idiopathic encephalitis. Metagenomics analyses of tissue pools revealed novel viruses in the genera Circoviridae, Parvoviridae, Anelloviridae, Polyomaviridae, and Papillomaviridae. The circovirus and parvovirus were of particular interest due to their potential importance as pathogens. We characterized the genomes of these viruses and subsequently screened bears by PCR to determine their prevalence. The circovirus (Ursus americanus circovirus, UaCV) was detected at a high prevalence (10/16, 67%), and the chaphamaparvovirus (Ursus americanus parvovirus, UaPV) was found in a single bear. We showed that UaCV is present in liver, spleen/lymph node, and brain tissue of selected cases by in situ hybridization (ISH) and PCR. Infections were detected in cases of idiopathic encephalitis and in cases without inflammatory brain lesions. Infection status was not clearly correlated with disease, and the significance of these infections remains unclear. Given the known pathogenicity of a closely related mammalian circovirus, and the complex manifestations of circovirus-associated diseases, we suggest that UaCV warrants further study as a possible cause or contributor to disease in American black bears.
Collapse
Affiliation(s)
- Charles E. Alex
- Department of Pathology, Microbiology, and Immunology, University of California—Davis School of Veterinary Medicine, Davis, California, United States of America
| | - Elizabeth Fahsbender
- Vitalant Research Institute, San Francisco, California, United States of America
- Department of Laboratory Medicine, University of California—San Francisco, San Francisco, California, United States of America
| | - Eda Altan
- Vitalant Research Institute, San Francisco, California, United States of America
- Department of Laboratory Medicine, University of California—San Francisco, San Francisco, California, United States of America
| | - Robert Bildfell
- Department of Biomedical Sciences, Carlson College of Veterinary Medicine, Oregon State University, Corvallis, Oregon, United States of America
- Oregon Veterinary Diagnostic Laboratory, Carlson College of Veterinary Medicine, Oregon State University, Corvallis, Oregon, United States of America
| | - Peregrine Wolff
- Nevada Department of Wildlife, Reno, Nevada, United States of America
| | - Ling Jin
- Department of Biomedical Sciences, Carlson College of Veterinary Medicine, Oregon State University, Corvallis, Oregon, United States of America
- Oregon Veterinary Diagnostic Laboratory, Carlson College of Veterinary Medicine, Oregon State University, Corvallis, Oregon, United States of America
| | - Wendy Black
- Oregon Veterinary Diagnostic Laboratory, Carlson College of Veterinary Medicine, Oregon State University, Corvallis, Oregon, United States of America
| | - Kenneth Jackson
- Department of Pathology, Microbiology, and Immunology, University of California—Davis School of Veterinary Medicine, Davis, California, United States of America
| | - Leslie Woods
- California Animal Health and Food Safety Laboratory, Davis, California, United States of America
| | - Brandon Munk
- California Department of Fish and Wildlife, Rancho Cordova, California, United States of America
| | - Tiffany Tse
- Department of Pathology, Microbiology, and Immunology, University of California—Davis School of Veterinary Medicine, Davis, California, United States of America
| | - Eric Delwart
- Vitalant Research Institute, San Francisco, California, United States of America
- Department of Laboratory Medicine, University of California—San Francisco, San Francisco, California, United States of America
| | - Patricia A. Pesavento
- Department of Pathology, Microbiology, and Immunology, University of California—Davis School of Veterinary Medicine, Davis, California, United States of America
- * E-mail:
| |
Collapse
|
4
|
Grinde B. Viruses belonging to Anelloviridae or Circoviridae as a possible cause of chronic fatigue. J Transl Med 2020; 18:485. [PMID: 33317538 PMCID: PMC7734913 DOI: 10.1186/s12967-020-02666-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 12/04/2020] [Indexed: 11/10/2022] Open
Abstract
Chronic fatigue often starts with an acute viral infection-as witnessed in the case of SARS-CoV-2-but indirect consequences of these infections are presumably the actual cause of the condition. As recently reviewed in this journal, the culprit could be a virus already present in the patient. The review covers several types of viruses, but concludes that the question is still open. The focus is on well known, pathogenic viruses for which there are ample diagnostic tools. I argue that there is one lesser-known group of viruses, the related anello- and circoviruses, which ought to be investigated. More or less everyone harbours at least one strain of these viruses in the blood, while not in the spinal fluid. They normally replicate at a low level, but their activity increases in an immune suppressed host; and there are cases where they do reach the brain. The initial infection could facilitate their access to the brain.
Collapse
Affiliation(s)
- Bjørn Grinde
- Division of Mental and Physical Health, Norwegian Institute of Public Health, Skøyen, PO Box 222, 0213, Oslo, Norway.
| |
Collapse
|
5
|
Disease surveillance in England and Wales, February 2019. Vet Rec 2019; 184:271-275. [PMID: 30819857 DOI: 10.1136/vr.l937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
6
|
Affiliation(s)
- Yashpal Singh Malik
- ICAR-Indian Veterinary Research Institute (ICAR-IVRI), Izatnagar, Uttar Pradesh India
| | - Raj Kumar Singh
- ICAR-Indian Veterinary Research Institute (ICAR-IVRI), Izatnagar, Uttar Pradesh India
| | - Mahendra Pal Yadav
- ICAR-Indian Veterinary Research Institute (ICAR-IVRI), Izatnagar, Uttar Pradesh, India, Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut, India
| |
Collapse
|
7
|
Pan Y, Li P, Jia R, Wang M, Yin Z, Cheng A. Regulation of Apoptosis During Porcine Circovirus Type 2 Infection. Front Microbiol 2018; 9:2086. [PMID: 30233552 PMCID: PMC6131304 DOI: 10.3389/fmicb.2018.02086] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Accepted: 08/15/2018] [Indexed: 12/19/2022] Open
Abstract
Apoptosis, an indispensable innate immune mechanism, regulates cellular homeostasis by removing unnecessary or damaged cells. It contains three signaling pathways: the mitochondria-mediated pathway, the death receptor pathway and the endoplasmic reticulum pathway. The importance of apoptosis in host defenses is stressed by the observation that multiple viruses have evolved various strategies to inhibit apoptosis, thereby blunting the host immune responses and promoting viral propagation. Porcine Circovirus type 2 (PCV2) utilizes various strategies to induce or inhibit programmed cell death. In this article, we review the latest research progress of the apoptosis mechanisms during infection with PCV2, including several proteins of PCV2 regulate apoptosis via interacting with host proteins and multiple signaling pathways involved in PCV2-induced apoptosis, which provides scientific basis for the pathogenesis and prevention of PCV2.
Collapse
Affiliation(s)
- Yuhong Pan
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Pengfei Li
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Renyong Jia
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Mingshu Wang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Zhongqiong Yin
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Anchun Cheng
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| |
Collapse
|
8
|
Comparison of Different In Situ Hybridization Techniques for the Detection of Various RNA and DNA Viruses. Viruses 2018; 10:v10070384. [PMID: 30037026 PMCID: PMC6071121 DOI: 10.3390/v10070384] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 07/13/2018] [Accepted: 07/18/2018] [Indexed: 12/14/2022] Open
Abstract
In situ hybridization (ISH) is a technique to determine potential correlations between viruses and lesions. The aim of the study was to compare ISH techniques for the detection of various viruses in different tissues. Tested RNA viruses include atypical porcine pestivirus (APPV) in the cerebellum of pigs, equine and bovine hepacivirus (EqHV, BovHepV) in the liver of horses and cattle, respectively, and Schmallenberg virus (SBV) in the cerebrum of goats. Examined DNA viruses comprise canine bocavirus 2 (CBoV-2) in the intestine of dogs, porcine bocavirus (PBoV) in the spinal cord of pigs and porcine circovirus 2 (PCV-2) in cerebrum, lymph node, and lung of pigs. ISH with self-designed digoxigenin-labelled RNA probes revealed a positive signal for SBV, CBoV-2, and PCV-2, whereas it was lacking for APPV, BovHepV, EqHV, and PBoV. Commercially produced digoxigenin-labelled DNA probes detected CBoV-2 and PCV-2, but failed to detect PBoV. ISH with a commercially available fluorescent ISH (FISH)-RNA probe mix identified nucleic acids of all tested viruses. The detection rate and the cell-associated positive area using the FISH-RNA probe mix was highest compared to the results using other probes and protocols, representing a major benefit of this method. Nevertheless, there are differences in costs and procedure time.
Collapse
|
9
|
Tian D, Sooryanarain H, Matzinger SR, Gauger PC, Karuppannan AK, Elankumaran S, Opriessnig T, Meng XJ. Protective efficacy of a virus-vectored multi-component vaccine against porcine reproductive and respiratory syndrome virus, porcine circovirus type 2 and swine influenza virus. J Gen Virol 2017; 98:3026-3036. [DOI: 10.1099/jgv.0.000964] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Affiliation(s)
- Debin Tian
- Department of Biomedical Sciences and Pathobiology, Virginia Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Harini Sooryanarain
- Department of Biomedical Sciences and Pathobiology, Virginia Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Shannon R. Matzinger
- Department of Biomedical Sciences and Pathobiology, Virginia Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Phil C. Gauger
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Anbu K. Karuppannan
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Subbiah Elankumaran
- Department of Biomedical Sciences and Pathobiology, Virginia Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Tanja Opriessnig
- The Roslin Institute, University of Edinburgh, Midlothian, Scotland, UK
| | - Xiang-Jin Meng
- Department of Biomedical Sciences and Pathobiology, Virginia Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| |
Collapse
|
10
|
Spiekermeier I, Freitag M, Baumgärtner W. [Interstitial nephritis in pigs]. Tierarztl Prax Ausg G Grosstiere Nutztiere 2017; 45:170079. [PMID: 28880043 DOI: 10.15653/tpg-170079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Accepted: 06/29/2017] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Interstitial nephritis as a form of renal diseases can be found frequently among pigs. Nevertheless, prevalence and aetiology need to be investigated in more detail as reports about detailed analysis are lacking. MATERIAL AND METHODS In the present study, a total of 169 kidneys of conventionally and organically raised pigs were randomly chosen at slaughter and classified according to the degree of inflammation and the participating inflammatory cells. Moreover, PCV2 as an infectious agent was analysed by immunohistochemistry and in-situ hybridisation. RESULTS All of the investigated kidneys displayed mild interstitial lesions. Inflammatory cells included lymphocytes, macrophages, plasma cells, eosinophilic and neutrophilic granulocytes. Significant (p ≤ 0.0001) differences concerning the grade of inflammation and inflammatory cell occurrence could be observed between kidneys of conventionally and organically raised pigs. In comparison to conventionally raised pigs organically raised pigs showed significant (p ≤ 0.0001) more frequently a mild form of nephritis as well as a significant (p ≤ 0.0001) more frequent occurrence of lymphocytes and macrophages. In contrast to that, conventionally raised pigs had a significant (p ≤ 0.0001) higher occurrence rate of a mild to moderate form of nephritis as well as a significant (p ≤ 0.0001) higher level in occurrence of lymphocytes, macrophages, plasma cells, and neutrophilic granulocytes when compared to organically raised pigs. PCV2 DNA was detected in the kidney of only one animal. CONCLUSION Interstitial nephritis was found in conventionally and organically raised pigs and PCV2 was ruled out as a major pathogen for interstitial nephritis in slaughter pigs. CLINICAL RELEVANCE Because of the high prevalence and unknown cause further investigations are necessary to delineate the clinic relevance of this alteration and its pathogenesis.
Collapse
Affiliation(s)
- Ines Spiekermeier
- Dr. Ines Spiekermeier, Landwirtschaftskammer Niedersachsen, Schweinegesundheitsdienst, Mars-la-Tour-Straße 1-13, 26121 Oldenburg, E-Mail:
| | | | | |
Collapse
|
11
|
Persistent Morbillivirus Infection Leads to Altered Cortactin Distribution in Histiocytic Sarcoma Cells with Decreased Cellular Migration Capacity. PLoS One 2016; 11:e0167517. [PMID: 27911942 PMCID: PMC5135102 DOI: 10.1371/journal.pone.0167517] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 11/15/2016] [Indexed: 12/04/2022] Open
Abstract
Histiocytic sarcomas represent rare but fatal neoplasms in humans. Based on the absence of a commercially available human histiocytic sarcoma cell line the frequently affected dog displays a suitable translational model. Canine distemper virus, closely related to measles virus, is a highly promising candidate for oncolytic virotherapy. Therapeutic failures in patients are mostly associated with tumour invasion and metastasis often induced by misdirected cytoskeletal protein activities. Thus, the impact of persistent canine distemper virus infection on the cytoskeletal protein cortactin, which is frequently overexpressed in human cancers with poor prognosis, was investigated in vitro in a canine histiocytic sarcoma cell line (DH82). Though phagocytic activity, proliferation and apoptotic rate were unaltered, a significantly reduced migration activity compared to controls (6 hours and 1 day after seeding) accompanied by a decreased number of cortactin mRNA transcripts (1 day) was detected. Furthermore, persistently canine distemper virus infected DH82 cells showed a predominant diffuse intracytoplasmic cortactin distribution at 6 hours and 1 day compared to controls with a prominent membranous expression pattern (p ≤ 0.05). Summarized, persistent canine distemper virus infection induces reduced tumour cell migration associated with an altered intracellular cortactin distribution, indicating cytoskeletal changes as one of the major pathways of virus-associated inhibition of tumour spread.
Collapse
|
12
|
Marks FS, Almeida LL, Driemeier D, Canal C, Barcellos DESN, Guimarães JA, Reck J. Porcine circovirus 2 (PCV2) increases the expression of endothelial adhesion/junction molecules. Braz J Microbiol 2016; 47:870-875. [PMID: 27522934 PMCID: PMC5052378 DOI: 10.1016/j.bjm.2016.07.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 02/29/2016] [Indexed: 12/18/2022] Open
Abstract
Porcine circovirus type 2 (PCV2) is the primary causative agent of porcine circovirus disease, a complex multisystem syndrome in domestic pigs. Despite the significant economic losses caused by porcine circovirus disease, the mechanisms of pathogenesis underlying the clinical findings remain largely unclear. As various reports have highlighted the potential key role of vascular lesions in the pathogenesis of porcine circovirus disease, the aim of this work was to investigate effects of PCV2 infection on vascular endothelial cells, focusing on cell viability and expression of adhesion/junction molecules. PCV2 infection reduced endothelial cell viability, while viral infection did not affected the viability of several other classical cell lines. Also, PCV2 infection in endothelial cells displayed a dual/biphasic effect: initially, infection increased ICAM-1 expression, which can favor leukocyte recruitment and emigration to tissues and possibly inducing characteristic porcine circovirus disease inflammatory lesions; then, secondarily, infection caused an increase in zonula occludens 1 tight junction protein (ZO-1) expression, which in turn can result in difficulties for cell traffic across the endothelium and a potential impairment the immune response in peripheral tissues. These virus-induced endothelial changes could directly impact the inflammatory process of porcine circovirus disease and associated vascular/immune system disturbances. Data suggest that, among the wide range of effects induced by PCV2 on the host, endothelial modulation can be a pivotal process which can help to explain PCV2 pathogenesis in some porcine circovirus disease presentations.
Collapse
Affiliation(s)
| | - Laura L Almeida
- Fundação Estadual de Pesquisa Agropecuária (FEPAGRO), Instituto de Pesquisas Veterinárias Desidério Finamor (IPVDF), Eldorado do Sul, RS, Brazil
| | - David Driemeier
- Universidade Federal do Rio Grande do Sul (UFRGS), Faculdade de Veterinária, Porto Alegre, RS, Brazil
| | - Cláudio Canal
- Universidade Federal do Rio Grande do Sul (UFRGS), Faculdade de Veterinária, Porto Alegre, RS, Brazil
| | - David E S N Barcellos
- Universidade Federal do Rio Grande do Sul (UFRGS), Faculdade de Veterinária, Porto Alegre, RS, Brazil
| | - Jorge A Guimarães
- Universidade Federal do Rio Grande do Sul (UFRGS), Centro de Biotecnologia, Porto Alegre, RS, Brazil
| | - José Reck
- Fundação Estadual de Pesquisa Agropecuária (FEPAGRO), Instituto de Pesquisas Veterinárias Desidério Finamor (IPVDF), Eldorado do Sul, RS, Brazil.
| |
Collapse
|
13
|
Abstract
Swine are used in biomedical research as models for biomedical research and for teaching. This chapter covers normative biology and behavior along with common and emerging swine diseases. Xenotransplantation is discussed along with similarities and differences of swine immunology.
Collapse
Affiliation(s)
- Kristi L. Helke
- Departments of Comparative Medicine and Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, USA
| | | | - Raimon Duran-Struuck
- Columbia Center of Translational Immunology, Department of Surgery; Institute of Comparative Medicine; Columbia University Medical Center, New York, NY, USA
| | - M. Michael Swindle
- Medical University of South Carolina, Department of Comparative Medicine and Department of Surgery, Charleston, SC, USA
| |
Collapse
|
14
|
Resendes AR, Segalés J. Characterization of vascular lesions in pigs affected by porcine circovirus type 2-systemic disease. Vet Pathol 2014; 52:497-504. [PMID: 24963088 DOI: 10.1177/0300985814540542] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Vascular lesions and their association with porcine circovirus type 2 (PCV2) were evaluated in multiple organs from 10 pigs affected with PCV2-systemic disease (PCV2-SD). Animals had vascular lesions in multiple organs, consisting of lymphohistiocytic lymphangitis and/or phlebitis, mild to severe necrotizing arteritis, and thrombosis within splenic arterioles and choroid plexus capillaries. Variable amounts of PCV2 nucleic acid detected by in situ hybridization were present within endothelial cells, tunica media myocytes, and perivascular and/or intralesional inflammatory cell infiltrates. PCV2 nucleic acid was detected within endothelial cells of both lymphatic and blood vessels without lesions in the associated tissues. Necrotizing arteritis was principally present in lymph nodes and kidney and consisted of degeneration, necrosis, and pyknosis of myocytes, often with intracytoplasmic, brightly eosinophilic inclusion bodies that were strongly positive for PCV2 nucleic acid. Segmental or circumferential fibrinoid necrosis was mainly present in vessels of the lymph node, spleen, and choroid plexus and was variably associated with PCV2 nucleic acid. Severe lymphangitis associated with strong intralesional PCV2 labeling was frequently detected within the mesenteric and mediastinal lymph nodes and the lamina propria of the ileum. In most tissues, medium and large lymphatics and/or veins often had disruption of the intima and mild mononuclear inflammatory cell infiltration that was variably associated with PCV2 nucleic acid. The present study indicates that vasculitis is a frequent finding in natural cases of PCV2-SD and that PCV2 may have a direct cytopathic effect on tunica media myocytes of small- and medium-sized arteries as well as endothelium.
Collapse
Affiliation(s)
- A R Resendes
- Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
| | - J Segalés
- Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain Department de Sanitat i d'Anatomia Animals, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
| |
Collapse
|
15
|
Novel Gyroviruses, including Chicken Anaemia Virus, in Clinical and Chicken Samples from South Africa. Adv Virol 2014; 2014:321284. [PMID: 24876841 PMCID: PMC4022007 DOI: 10.1155/2014/321284] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 03/17/2014] [Indexed: 11/18/2022] Open
Abstract
Introduction. Chicken anaemia virus, CAV, was until recently the only member of the Gyrovirus genus. 6 novel gyroviruses, AGV2, HGyV1, and GyV3-6, have since been discovered in human and chicken samples. Methods. PCR amplification of the VP2 gene was used to detect AGV2/HGyV1, GyV3, and CAV in a range of clinical samples including stool, respiratory, CSF, and HIV-positive plasma. Screening of fresh local chicken meat was also performed. Results. AGV2/HGyV1 or GyV3 was detected in stools from healthy children (17/49, 34.7%) and patients with diarrhoea (22/149, 14.8%). 1.2% (3/246) nasopharyngeal respiratory samples were positive. No AGV2/HGyV1 or GyV3 was detected in nasal swabs from wheezing patients, in CSF from patients with meningitis, and in HIVpositive plasma. CAV was found in 51% (25/49) of stools from healthy children and 16% (24/149) in diarrhoea samples. Screening of 28 chicken samples showed a higher prevalence of gyrovirus (20/28, 71%) compared to CAV (1/28, 3.6%). Phylogenetic analysis of the CAV VP1 gene showed South African sequences clustering with Brazilian isolates from genotypes D2 and A2. Conclusion. Novel gyroviruses, including CAV, are present in the South African population with diarrhoea and respiratory illness as well as in healthy children. Their presence suggests an origin from chicken meat consumption.
Collapse
|
16
|
Li L, McGraw S, Zhu K, Leutenegger CM, Marks SL, Kubiski S, Gaffney P, Dela Cruz FN, Wang C, Delwart E, Pesavento PA. Circovirus in tissues of dogs with vasculitis and hemorrhage. Emerg Infect Dis 2013; 19:534-41. [PMID: 23628223 PMCID: PMC3647419 DOI: 10.3201/eid1904.121390] [Citation(s) in RCA: 112] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
We characterized the complete genome of a novel dog circovirus (DogCV) from the liver of a dog with severe hemorrhagic gastroenteritis, vasculitis, and granulomatous lymphadenitis. DogCV was detected by PCR in fecal samples from 19/168 (11.3%) dogs with diarrhea and 14/204 (6.9%) healthy dogs and in blood from 19/409 (3.3%) of dogs with thrombocytopenia and neutropenia, fever of unknown origin, or past tick bite. Co-infection with other canine pathogens was detected for 13/19 (68%) DogCV-positive dogs with diarrhea. DogCV capsid proteins from different dogs varied by up to 8%. In situ hybridization and transmission electron microscopy detected DogCV in the lymph nodes and spleens of 4 dogs with vascular compromise and histiocytic inflammation. The detection of a circovirus in tissues of dogs expands the known tropism of these viruses to a second mammalian host. Our results indicate that circovirus, alone or in co-infection with other pathogens, might contribute to illness and death in dogs.
Collapse
Affiliation(s)
- Linlin Li
- Blood Systems Research Institute, and Department of Laboratory Medicine, University of California, San Francisco, California, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Wei L, Zhu S, Wang J, Zhang C, Quan R, Yan X, Liu J. Regulatory role of ASK1 in porcine circovirus type 2-induced apoptosis. Virology 2013; 447:285-91. [PMID: 24210125 DOI: 10.1016/j.virol.2013.09.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2013] [Revised: 08/14/2013] [Accepted: 09/12/2013] [Indexed: 01/17/2023]
Abstract
Porcine circovirus type 2 (PCV2), a major causative agent of postweaning multisystemic wasting syndrome which is an emerging and important swine disease, can induce apoptotic responses in vitro and in vivo. However, the molecular mechanism of PCV2-induced apoptosis is not well understood. Apoptosis signal-regulating kinase 1 (ASK1), serves as an upstream enzyme that activates the JNK and p38 MAPK pathways, has been shown to play a target role in the regulation of apoptosis. Here, we showed that PCV2 infection induced ASK1 phosphorylation which preceded activation of JNK1/2 and p38 signaling in the cultured cells, and that the phosphatidylinostol 3-kinase (PI3K)/Akt signaling triggered by PCV2 infection limited the extent of JNK1/2 and p38 activation and thereby apoptotic cell death. Furthermore, inhibition of JNK and p38 activation is associated with PI3K-dependent negative-regulation of ASK1 in the PCV2-infected cells. These results indicate an important regulatory role of ASK1 in PCV2-induced apoptotic responses.
Collapse
Affiliation(s)
- Li Wei
- Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agriculture and Forestry Sciences, No. 9 Shuguang Garden Middle Road, Haidian District, Beijing 100097, People's Republic of China
| | | | | | | | | | | | | |
Collapse
|
18
|
Zlotowski P, Pavarini SP, Bandinelli MB, Langohr IM, Driemeier D. Paralysis in pigs with spinal cord injury due to porcine circovirus type 2 (PCV-2) infection. Vet Rec 2013; 172:637. [DOI: 10.1136/vr.101409] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- P. Zlotowski
- Laboratory of Veterinary Pathology; Universidade Federal do Rio Grande do Sul (UFRGS); College of Veterinary Medicine; Porto Alegre Brazil
| | - S. P. Pavarini
- Laboratory of Veterinary Pathology; Universidade Federal do Rio Grande do Sul (UFRGS); College of Veterinary Medicine; Porto Alegre Brazil
| | - M. B. Bandinelli
- Laboratory of Veterinary Pathology; Universidade Federal do Rio Grande do Sul (UFRGS); College of Veterinary Medicine; Porto Alegre Brazil
| | - I. M. Langohr
- Department of Pathobiology and Diagnostic Investigation Michigan; Michigan State University; Michigan Michigan USA
| | - D. Driemeier
- Department of Veterinary Pathology; UFRGS; Av. Bento Gonçalves, 9090 Porto Alegre RS 91540-000 Brazil
| |
Collapse
|
19
|
Activation of the phosphatidylinositol 3-kinase/Akt signaling pathway during porcine circovirus type 2 infection facilitates cell survival and viral replication. J Virol 2012; 86:13589-97. [PMID: 23035228 DOI: 10.1128/jvi.01697-12] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Virus infection activates host cellular signaling pathways, including the phosphatidylinositol 3-kinase (PI3K)/Akt pathway, which regulates diverse cellular activities related to cell growth, survival, and apoptosis. The present study demonstrated for the first time that porcine circovirus type 2 (PCV2), a major causative agent of postweaning multisystemic wasting syndrome, which is an emerging and important swine disease, can transiently induce the PI3K/Akt pathway in cultured cells at an early step during PCV2 infection. Activation of the PI3K/Akt signal was also induced by UV-irradiated PCV2, indicating that virus replication was not required for this induction. Inhibition of PI3K activation leads to reduced virus yield, which is associated with decreased viral DNA replication and lower virus protein expression. However, inhibition of PI3K activation greatly enhanced apoptotic responses as evidenced by the cleavage of poly-ADP ribose polymerase and caspase-3 as well as DNA fragmentation using terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling staining during the early stage of PCV2 infection. Furthermore, the pancaspase inhibitor zVAD.fmk alleviated the reduction in Akt phosphorylation levels by inhibiting PI3K activation, indicating that the signaling promotes cell survival and thereby favors viral replication. These results reveal that an antiapoptotic role for the PI3K/Akt pathway induced by PCV2 infection to suppress premature apoptosis for improved virus growth after infection, extending our understanding of the molecular mechanism of PCV2 infection.
Collapse
|
20
|
Opriessnig T, Langohr I. Current State of Knowledge on Porcine Circovirus Type 2-Associated Lesions. Vet Pathol 2012; 50:23-38. [DOI: 10.1177/0300985812450726] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Porcine circovirus type 2 (PCV2), a small single-stranded DNA virus, was initially discovered in 1998 and is highly prevalent in the domestic pig population. Disease manifestations associated with PCV2 include postweaning multisystemic wasting disease (PMWS), enteric disease, respiratory disease, porcine dermatitis and nephropathy syndrome (PDNS), and reproductive failure. Although these clinical manifestations involve different organ systems, there is considerable overlap in clinical expression of disease and presence of lesions between pigs and within herds. It is now widely accepted that PCV2 can be further subdivided into different types, of which PCV2a and PCV2b are present worldwide and of greatest importance. This review will focus on PCV2-associated lesions in different organ systems.
Collapse
Affiliation(s)
- T. Opriessnig
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa
| | - I. Langohr
- Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, Michigan
| |
Collapse
|
21
|
Segalés J. Porcine circovirus type 2 (PCV2) infections: Clinical signs, pathology and laboratory diagnosis. Virus Res 2012; 164:10-9. [DOI: 10.1016/j.virusres.2011.10.007] [Citation(s) in RCA: 384] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Revised: 10/10/2011] [Accepted: 10/11/2011] [Indexed: 12/18/2022]
|
22
|
Sinha A, Schalk S, Lager KM, Wang C, Opriessnig T. Singular PCV2a or PCV2b infection results in apoptosis of hepatocytes in clinically affected gnotobiotic pigs. Res Vet Sci 2012; 92:151-6. [DOI: 10.1016/j.rvsc.2010.10.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2010] [Revised: 10/04/2010] [Accepted: 10/14/2010] [Indexed: 10/18/2022]
|
23
|
Vaccination of dams increases antibody titer and improves growth parameters in finisher pigs subclinically infected with porcine circovirus type 2. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2011; 18:1644-9. [PMID: 21852549 DOI: 10.1128/cvi.05183-11] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Porcine circovirus type 2 (PCV2) is the obligate infectious agent in postweaning multisystemic wasting syndrome (PMWS) of pigs. To control PMWS, we vaccinated dams at 4 and 2 weeks before pregnancy and again in the 12th week of gestation with an inactivated PCV2 vaccine (Circovac). Two producer farms run under the control of Swiss Swine Health Organization were selected for the experiment. Previously, in one farm PMWS was diagnosed on pigs after weaning, whereas in the other farm, pigs wasted during the fattening period. For the experiments 113 dams were randomly vaccinated, and 111 dams were sham injected. Vaccination increased serum antibodies in dams 3- to 9-fold, accompanied by serum antibody titer increases in their offspring. In the sixth week of life, progeny from vaccinated dams had about the same IgG antibody titers as progeny of unvaccinated dams at the third day of life. In sera of vaccinated dams only low concentrations of PCV2 DNA were detected, and no progeny developed PMWS. Interestingly, at day 56 four progeny of unvaccinated dams tested positive for anti-PCV2 IgM antibodies, indicating a primary infection with PCV2. Of economic importance is the observation that progeny of vaccinated dams had a significantly higher daily weight gain in the fattening period (farm X, +51 g/day; farm Y, +30 g/day) and thus a shortened fattening period of about 6 days compared to progeny of controls. To our knowledge this is the first demonstration of subclinical circovirus infection and its effects on growth performance of fattening pigs by vaccination of dams.
Collapse
|
24
|
Szeredi L, Dán A, Solymosi N, Cságola A, Tuboly T. Association of porcine circovirus type 2 with vascular lesions in porcine pneumonia. Vet Pathol 2011; 49:264-70. [PMID: 21551427 DOI: 10.1177/0300985811406888] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The aim of this study was to evaluate the vasculature in porcine circovirus type 2-infected (PCV2-infected) lungs and to identify the PCV2 subtypes involved in porcine pneumonia. Pulmonary samples from 140 pigs, 2 weeks to 7 months of age, from 36 Hungarian commercial herds with clinical signs of respiratory disease were examined for the presence of respiratory pathogens, with bacterial culture, pathologic evaluation, and immunohistochemistry for PCV2, porcine reproductive respiratory syndrome virus, and swine influenza virus. PCV2 was the most commonly identified pathogen (49 cases) among the 74 of 140 cases (53%) with respiratory pathogens. PCV2 was detected immunohistochemically in the wall of 13% to 100% of pulmonary vessels (mean, 89%) in 38 of 49 cases (78%). Detection of PCV2 antigen was positively correlated with the presence of vascular lesions (P < .001, odds ratio [OR]: 159.54). Other pathogens capable of vascular injury in swine were found in 29 of 49 of the PCV2-positive cases (59%). The probability of detecting vascular lesions in PCV2-infected lung was higher than in infection with porcine reproductive respiratory syndrome virus (P < .002, OR: 14.63), Pasteurella multocida infection (P < .001, OR: 5.75), or Streptococcus spp. infection (not significant, OR: 1.45). Sequence analysis of open reading frame 2 amplicons was possible in 6 PCV2-positive cases, from which 5 cases proved to be PCV2b subtype and 1 case, PCV2a subtype. In conclusion, PCV2 antigen was commonly colocalized with pulmonary vascular lesions in pneumonia in Hungarian swine, and PCV2b was the dominant subtype.
Collapse
Affiliation(s)
- L Szeredi
- Central Agricultural Office Veterinary Diagnostic Directorate, Tábornok u. 2, H-1149, Budapest, Hungary.
| | | | | | | | | |
Collapse
|
25
|
Galindo-Cardiel I, Grau-Roma L, Pérez-Maíllo M, Segalés J. Characterization of necrotizing lymphadenitis associated with porcine circovirus type 2 infection. J Comp Pathol 2010; 144:63-9. [PMID: 20708744 DOI: 10.1016/j.jcpa.2010.06.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2009] [Revised: 04/14/2010] [Accepted: 06/14/2010] [Indexed: 12/14/2022]
Abstract
Necrotizing lymphadenitis is observed in approximately 2% of pigs affected by post-weaning multisystemic wasting syndrome (PMWS). The pathogenesis of the lesion has been linked to apoptosis induced by porcine circovirus type 2 (PCV2). The aim of the present study was to gain further insights into PCV2-associated lymphoid necrosis in pigs with PMWS. Three groups of animals were studied: (1) PMWS-affected pigs with necrotizing lymphadenitis (n=5), (2) PMWS-affected pigs without necrotizing lymphadenitis (n=5) and (3) healthy pigs with no PMWS-related lesions (n=5). Investigations performed included immunohistochemical evaluation of the expression of cleaved caspase-3 and von Willebrand factor, Mallory's staining for fibrin and in-situ hybridization for detection of the PCV2 genome. The results of the study suggested that lymphoid necrosis in PMWS-affected pigs may be related to hypertrophy and hyperplasia of high endothelial venules (HEVs). The mechanism underlying these changes in HEVs was not clearly defined, but necrotizing lymphadenitis in pigs with PMWS may develop following vascular damage with thrombosis and subsequent follicular necrosis. Apoptosis was not found to be involved in lymphocyte depletion in PMWS or in PMWS-associated necrotizing lymphadenitis.
Collapse
Affiliation(s)
- I Galindo-Cardiel
- Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Barcelona, Spain.
| | | | | | | |
Collapse
|
26
|
Langohr IM, Stevenson GW, Nelson EA, Lenz SD, HogenEsch H, Wei H, Pogranichniy RM. Vascular lesions in pigs experimentally infected with porcine circovirus type 2 serogroup B. Vet Pathol 2010; 47:140-7. [PMID: 20080495 DOI: 10.1177/0300985809352793] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Vasculitis is a hallmark lesion of the severe form of systemic porcine circovirus-associated disease (PCVAD). In 2 experimental studies with porcine circovirus type 2 serogroup b (PCV2b), 2 pigs developed fatal PCVAD with acute vasculitis, and 5 related pigs developed chronic lymphohistiocytic and plasmacytic peri- and endarteritis. Five of these pigs (1 with acute vasculitis and 4 with chronic vasculitis) had also been inoculated with bovine viral diarrhea virus type 1 (BVDV1) or BVDV1-like virus. Vascular lesions were similar, independent of whether pigs had been inoculated singly with PCV2b or dually with PCV2b and BVDV1 or BVDV1-like virus. The acute vasculitis was accompanied by marked pulmonary and mesenteric edema and pleural effusion. In situ hybridization demonstrated abundant intracytoplasmic porcine circovirus type 2 (PCV2) nucleic acid in endothelial, smooth muscle-like, and inflammatory cells within and around affected arteries. The pigs with lymphohistiocytic and plasmacytic vasculitis had lesions of systemic PCVAD, including multisystemic lymphoplasmacytic and histiocytic or granulomatous inflammation. PCV2 nucleic acid was detected in renal tubule epithelial cells, mononuclear inflammatory cells, and rare endothelial cells in noninflamed vessels in multiple tissues of these animals. The 2 pigs with acute vasculitis had no PCV2-specific antibodies (or a low titer of), whereas the pigs with lymphohistiocytic and plasmacytic vasculitis developed high antibody titers against this virus. These observations suggest that (1) acute vasculitis observed in the current studies is directly caused by PCV2b, (2) chronic vasculitis may in part be mediated by the subsequent immune response, and (3) host factors and viral strain may both contribute to vasculitis in animals infected with PCV2b.
Collapse
Affiliation(s)
- I M Langohr
- Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA.
| | | | | | | | | | | | | |
Collapse
|
27
|
Gillespie J, Opriessnig T, Meng XJ, Pelzer K, Buechner-Maxwell V. Porcine circovirus type 2 and porcine circovirus-associated disease. J Vet Intern Med 2009; 23:1151-63. [PMID: 19780932 PMCID: PMC7166794 DOI: 10.1111/j.1939-1676.2009.0389.x] [Citation(s) in RCA: 192] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2009] [Revised: 08/02/2009] [Accepted: 08/12/2009] [Indexed: 11/28/2022] Open
Abstract
Porcine circovirus type 2 (PCV2) belongs to the viral family Circoviridae and to the genus Circovirus. Circoviruses are small, single-stranded nonenveloped DNA viruses that have an unsegmented circular genome. PCV2 is the primary causative agent of several syndromes collectively known as porcine circovirus-associated disease (PCVAD). Many of the syndromes associated with PCVAD are a result of coinfection with PCV2 virus and other agents such as Mycoplasma and porcine reproductive and respiratory syndrome virus. PCV2 infection is present in every major swine-producing country in the world, and the number of identified cases of PCVAD is rapidly increasing. In the United States, the disease has cost producers an average of 3-4 dollars per pig with peak losses ranging up to 20 dollars per pig. The importance of this disease has stimulated investigations aimed at identifying risk factors associated with infection and minimizing these risks through modified management practices and development of vaccination strategies. This paper provides an overview of current knowledge relating to PCV2 and PCVAD with an emphasis on information relevant to the swine veterinarian.
Collapse
Affiliation(s)
- J Gillespie
- Department of Large Animal Clinical Sciences, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | | | | | | | | |
Collapse
|
28
|
Klein S, Wendt M, Baumgärtner W, Wohlsein P. Systemic toxoplasmosis and concurrent porcine circovirus-2 infection in a pig. J Comp Pathol 2009; 142:228-34. [PMID: 19740479 PMCID: PMC7094381 DOI: 10.1016/j.jcpa.2009.08.155] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Revised: 06/30/2009] [Accepted: 08/10/2009] [Indexed: 02/03/2023]
Abstract
Systemic toxoplasmosis and concurrent infection with porcine circovirus-2 (PCV-2) was diagnosed in a fattening pig. Clinical examination of the herd showed that up to 30% of the pigs of this weight group suffered from severe respiratory signs including sneezing and coughing, with a mortality rate of up to 5%. Gross necropsy examination revealed severe interstitial pneumonia and generalized lymphadenopathy. On microscopical examination there was necrotizing inflammation of the lung, adrenal glands and lymph nodes, associated with lymphoid depletion, cytoplasmic basophilic botryoid inclusion bodies and protozoal microorganisms. Infection with Toxoplasma gondii was confirmed by immunohistochemistry (IHC). Polymerase chain reaction analysis, in-situ hybridization and IHC confirmed systemic PCV-2 infection. These findings, associated with the respiratory signs and lesions in lymphoid tissues, are characteristic for post-weaning multisystemic wasting syndrome (PMWS). In this case, immunosuppression by PCV-2 may have triggered systemic toxoplasmosis, or immune stimulation caused by coinfection with T. gondii may have caused extensive replication of PCV-2.
Collapse
Affiliation(s)
- S Klein
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany
| | | | | | | |
Collapse
|
29
|
Marks FS, Reck J, Almeida LL, Berger M, Corrêa AMR, Driemeier D, Barcellos DESN, Guimarães JA, Termignoni C, Canal CW. Porcine circovirus 2 (PCV2) induces a procoagulant state in naturally infected swine and in cultured endothelial cells. Vet Microbiol 2009; 141:22-30. [PMID: 19733020 DOI: 10.1016/j.vetmic.2009.08.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 07/24/2009] [Accepted: 08/03/2009] [Indexed: 10/20/2022]
Abstract
Porcine circovirus 2 (PCV2) is the primary causative agent of porcine circovirus disease (PCVD). PCVD is an emerging disease that has been reported worldwide, associated with wasting, lymphoid depletion, enteritis, pneumonia, vasculitis, ischemic lesions, and necrotizing dermatitis. Although PCVD causes considerable economic losses, the pathogenesis of PCV2 has not been fully understood. The aim of the present work was to study the participation of hemostatic system and of vascular endothelium in PCV2 infection, as well as their possible role in PCVD pathogenesis. Our results showed that naturally PCV2-infected swine displayed a prothrombotic state in vivo, since a diminished coagulation time (recalcification time, activated partial thromboplastin time and prothrombin time), a higher platelet aggregation ability (despite a diminished platelet blood count), and an increased thrombin plasma activity (associated with a reduced fibrinogen level) were observed. The PCV2-infected animals showed vasculitis and positive staining for PCV2 antigen in capillary vessels. Furthermore, PCV2-infected endothelial cells displayed an activated phenotype, characterized by an increase in cell surface procoagulant activity. Moreover, the PCV2-infected endothelial cells pre-treated with exogenous thrombin displayed an increased viral load. This work reports, for the first time, the role of the hemostatic system and of endothelium in the pathogenesis and infectivity of PCV2. The study reinforces the importance of the phenomena which occur during PCV2 infection, and affords a better knowledge of the mechanisms behind the pathophysiology of PCVD.
Collapse
Affiliation(s)
- Fernanda S Marks
- Laboratório de Virologia, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves, 9090, 91540-000 Porto Alegre, RS, Brazil
| | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Retrospective study on the occurrence of porcine circovirus 2 infection and associated entities in Northern Germany. Vet Microbiol 2009; 138:27-33. [PMID: 19268497 DOI: 10.1016/j.vetmic.2009.02.005] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2008] [Revised: 01/28/2009] [Accepted: 02/03/2009] [Indexed: 11/24/2022]
Abstract
Porcine circovirus type 2 (PCV 2) represents a widespread, globally occurring pathogen with an increasing number of associated entities. To further elucidate the origin, spread and pathogenesis of PCV2 and associated changes archived material of pigs originating from Northern Germany and submitted for necropsy between 1961 and 1998 were investigated by using in situ hybridisation and polymerase chain reaction. PCV2 was first detected in a pig from 1962. However, incidence of detectable viral DNA and occurrence of PCV2-associated lesions varied substantially in the following years. The overall incidence of PCV2 infection was low between 1961 and 1984 (0-11.7%) and increased between 1985 and 1998 (14.3-53.3%). PCV2-associated pathological changes including postweaning multisystemic wasting syndrome (PMWS) and most likely porcine dermatitis and nephropathy syndrome (PDNS) were first observed in 1985. Selected sequence analyses of PCV2 DNA segments revealed high homology with current virus strains. In summary, findings showed that PCV2 has been present in the pig population in Northern Germany since 1962. This represents worldwide the earliest report about the detection of the PCV2 genome in pigs. Associated lesions such as PMWS and PDNS were not observed before 1985, indicating that virus infection alone does not seem to be sufficient enough to trigger the development of associated entities. Limited sequence analysis revealed no changes in the viral genome thus suggesting that other factors including environmental changes or co-infections with other agents might play a contributing role in the altered virulence of this pathogen and the occurrence of PCV2-associated lesions.
Collapse
|
31
|
Abstract
Porcine circovirus type 2 (PCV2) is the primary causative agent for porcine circovirus-associated disease (PCVAD). PCVAD has been the cause of considerable economic losses to the pork industry worldwide. The disease is primarily characterized by wasting, enlarged lymph nodes, jaundice and weight loss in affected weanling pigs. Several other complex syndromes involving reproductive failure, enteritis, pneumonia and necrotizing dermatitis have also been associated with PCV2 infection. Lymphoid depletion, which is the hallmark lesion of PCVAD, predisposes the host to immunosuppression. Disease progression is further complicated by co-infections with other bacterial and viral pathogens. Despite the availability of effective vaccines for the last 2 years, newly emerging strains of the virus have been reported to cause more severe outbreaks in parts of the USA and Canada. While knowledge of the biology and pathogenesis of PCV2 has progressed considerably over the last 12 years since the disease was recognized, many questions still remain to be answered.
Collapse
|
32
|
Is chronic fatigue syndrome caused by a rare brain infection of a common, normally benign virus? Med Hypotheses 2008; 71:270-4. [PMID: 18440157 DOI: 10.1016/j.mehy.2008.03.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2008] [Revised: 02/15/2008] [Accepted: 03/10/2008] [Indexed: 11/22/2022]
Abstract
Chronic fatigue syndrome (CFS) is a disabling disease of unknown aetiology. A variety of factors have been suggested as possible causes. Although the symptoms and clinical findings are heterogeneous, the syndrome is sufficiently distinct, at least in relation to the more obvious cases, that a common explanation seems likely. In this paper, it is proposed that the disease is caused by a ubiquitous, but normally benign virus, e.g., one of the circoviruses. Circoviruses are chronically present in a majority of people, but are rarely tested for diagnostically. Normally these viruses do not penetrate the blood-brain barrier, but exceptions have been reported, and related viruses cause disease in the central nervous system of animals. The flu-like illness that often precedes the onset of CFS may either suppress immune function, causing an increased viremia, and/or lower the blood-brain barrier. In both cases the result may be that a virus already present in the blood enters the brain. It is well known that zoonotic viruses typically are more malignant than viruses with a long history of host-virus evolution. Similarly, a virus reaching an unfamiliar organ may cause particular problems.
Collapse
|