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Ahlberg V, Hjertner B, Wallgren P, Hellman S, Lövgren Bengtsson K, Fossum C. Innate immune responses induced by the saponin adjuvant Matrix-M in specific pathogen free pigs. Vet Res 2017; 48:30. [PMID: 28532492 PMCID: PMC5441066 DOI: 10.1186/s13567-017-0437-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 04/27/2017] [Indexed: 12/05/2022] Open
Abstract
Saponin-based adjuvants have been widely used to enhance humoral and cellular immune responses in many species, but their mode of action is not fully understood. A characterization of the porcine transcriptional response to Matrix-M was performed in vitro using lymphocytes, monocytes or monocyte-derived dendritic cells (MoDCs) and in vivo. The effect of Matrix-M was also evaluated in specific pathogen free (SPF) pigs exposed to conventionally reared pigs. The pro-inflammatory cytokine genes IL1B and CXCL8 were up-regulated in monocytes and lymphocytes after Matrix-M exposure. Matrix-M also induced IL12B, IL17A and IFNG in lymphocytes and IFN-α gene expression in MoDCs. Several genes were indicated as up-regulated by Matrix-M in blood 18 h after injection, of which the genes for IFN-α and TLR2 could be statistically confirmed. Respiratory disease developed in all SPF pigs mixed with conventional pigs within 1–3 days. Two out of four SPF pigs injected with saline prior to contact exposure displayed systemic symptoms that was not recorded for the four pigs administered Matrix-M. Granulocyte counts, serum amyloid A levels and transcription of IL18 and TLR2 coincided with disease progression in the pigs. These results support further evaluation of Matrix-M as a possible enhancer of innate immune responses during critical moments in pig management.
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Affiliation(s)
- Viktor Ahlberg
- Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, SLU, Uppsala, Sweden
| | - Bernt Hjertner
- Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, SLU, Uppsala, Sweden
| | - Per Wallgren
- National Veterinary Institute, SVA, Uppsala, Sweden
| | - Stina Hellman
- Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, SLU, Uppsala, Sweden
| | | | - Caroline Fossum
- Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, SLU, Uppsala, Sweden.
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2
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Zheng LL, Wang YB, Li MF, Chen HY, Guo XP, Geng JW, Wang ZY, Wei ZY, Cui BA. Simultaneous detection of porcine parvovirus and porcine circovirus type 2 by duplex real-time PCR and amplicon melting curve analysis using SYBR Green. J Virol Methods 2012; 187:15-9. [PMID: 22771739 DOI: 10.1016/j.jviromet.2012.06.024] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Revised: 06/20/2012] [Accepted: 06/27/2012] [Indexed: 11/26/2022]
Abstract
The development of a SYBR Green-based duplex real-time PCR is described for simultaneous detection of porcine parvovirus (PPV) and porcine circovirus type 2 (PCV-2) genomes. Viral genomes were identified in the same sample by their distinctive melting temperature (T(m)) which is 77.5°C for PPV VP2 313bp amplicon and 82.3°C for PCV-2 ORF2 171bp amplicon, respectively. The detection limit of the method was 0.01TCID(50)/mL for PPV and PCV-2, about 10 times more sensitive than conventional PCR. In addition, PPV and PCV-2 viral load were measured in 126 field samples, confirming the sensitivity and specificity, and the result showed that 70/126 samples were positive for PPV and 92/126 samples were positive for PCV2 by the duplex real-time PCR. This method may be a useful alternative rapid and reliable method for the detection of PPV/PCV-2 co-infection.
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Affiliation(s)
- Lan-lan Zheng
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, Henan, China
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3
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Hornyák A, Bálint A, Farsang A, Balka G, Hakhverdyan M, Rasmussen TB, Blomberg J, Belák S. Detection of subgenomic mRNA of feline coronavirus by real-time polymerase chain reaction based on primer-probe energy transfer (P-sg-QPCR). J Virol Methods 2012; 181:155-63. [PMID: 22349594 PMCID: PMC7112857 DOI: 10.1016/j.jviromet.2012.01.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Revised: 01/23/2012] [Accepted: 01/30/2012] [Indexed: 12/31/2022]
Abstract
Feline infectious peritonitis is one of the most severe devastating diseases of the Felidae. Upon the appearance of clinical signs, a cure for the infected animal is impossible. Therefore rapid and proper diagnosis for both the presence of the causative agent, feline coronavirus (FCoV) and the manifestation of feline infectious peritonitis is of paramount importance. In the present work, a novel real-time RT-PCR method is described which is able to detect FCoV and to determine simultaneously the quantity of the viral RNA. The new assay combines the M gene subgenomic messenger RNA (sg-mRNA) detection and the quantitation of the genome copies of FCoV. In order to detect the broadest spectrum of potential FCoV variants and to achieve the most accurate results in the detection ability the new assay is applying the primer-probe energy transfer (PriProET) principle. This technology was chosen since PriProET is very robust to tolerate the nucleotide substitutions in the target area. Therefore, this technology provides a very broad-range system, which is able to detect simultaneously many variants of the virus(es) even if the target genomic regions show large scale of variations. The detection specificity of the new assay was proven by positive amplification from a set of nine different FCoV strains and negative from the tested non-coronaviral targets. Examination of faecal samples of healthy young cats, organ samples of perished animals, which suffered from feline infectious peritonitis, and cat leukocytes from uncertain clinical cases were also subjected to the assay. The sensitivity of the P-sg-QPCR method was high, since as few as 10 genome copies of FCoV were detected. The quantitative sg-mRNA detection method revealed more than 10–50,000 times increase of the M gene sg-mRNA in organ materials of feline infectious peritonitis cases, compared to those of the enteric FCoV variants present in the faeces of normal, healthy cats. These results indicate the applicability of the new P-sg-QPCR test as a powerful novel tool for the better detection and quantitation of FCoV and for the improved diagnosis of feline infectious peritonitis, this important disease of the Felidae, causing serious losses in the cat populations at a global scale.
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Affiliation(s)
- Akos Hornyák
- The Joint Research and Development Division, Department of Virology and Parasitology, The Swedish University of Agricultural Sciences, Ulls Väg 2B, SE-751 89 Uppsala, Sweden
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4
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McMenamy MJ, McKillen J, Hjertner B, Kiss I, Yacoub A, Leijon M, Duffy C, Belák S, Welsh M, Allan G. Development and comparison of a Primer-Probe Energy Transfer based assay and a 5' conjugated Minor Groove Binder assay for sensitive real-time PCR detection of infectious laryngotracheitis virus. J Virol Methods 2011; 175:149-55. [PMID: 21539859 DOI: 10.1016/j.jviromet.2011.04.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Revised: 04/14/2011] [Accepted: 04/19/2011] [Indexed: 11/17/2022]
Abstract
In this study the design and development of two real-time PCR assays for the rapid, sensitive and specific detection of infectious laryngotracheitis virus (ILTV) DNA is described. A Primer-Probe Energy Transfer (PriProET) assay and 5' conjugated Minor Groove Binder (MGB) method are compared and contrasted. Both have been designed to target the thymidine kinase gene of the ILTV genome. Both PriProET and MGB assays are capable of detecting 20 copies of a DNA standard per reaction and are linear from 2×10(8) to 2×10(2)copies/μl. Neither PriProET, nor MGB reacted with heterologous herpesviruses, indicating a high specificity of the two methods as novel tools for virus detection and identification. This study demonstrates the suitability of PriProET and 5' conjugated MGB probes as real-time PCR chemistries for the diagnosis of respiratory diseases caused by ILTV.
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Affiliation(s)
- M J McMenamy
- School of Biological Sciences, Queen's University Belfast, Belfast BT9 7BL, Northern Ireland, United Kingdom.
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Becskei Z, Aleksić-Kovačević S, Rusvai M, Balka G, Jakab C, Petrović T, Knežević M. Distribution of porcine circovirus 2 cap antigen in the lymphoid tissue of pigs affected by postweaning multisystemic wasting syndrome. Acta Vet Hung 2010; 58:483-98. [PMID: 21087918 DOI: 10.1556/avet.58.2010.4.9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The lymphatic organs of 50 pigs from a total of eight farms located at different sites in the epizootiological region of North Bačka County were studied to obtain data on the prevalence of circoviral infections in Serbia. All of the pigs examined had clinical signs suggestive of postweaning multisystemic wasting syndrome (PMWS). All pigs underwent necropsy and tissue samples were taken for histopathological, immunohistochemical (IHC) and PCR analysis. The presence of porcine circovirus 2 (PCV2) was established by PCR analysis in the organs of the pigs tested. The most frequent histopathological lesions of lymphoid tissue linked with the presence of positive immunostaining for PCV2 Cap antigen confirmed the existence of PMWS in all farms tested in North Bačka County. Using PCR, histopathological and IHC techniques, the presence of PMWS was proved in the Republic of Serbia. During necropsy, generalised enlargement of the lymph nodes was evident. The most common histopathological finding was lymphocyte depletion in the follicular and perifollicular areas of lymph nodes. Infiltration by macrophages was also recorded. By IHC analysis, the cytoplasm of macrophages was shown to contain a large amount of the ORF2-coded Cap antigen of PCV2. Lymphocyte depletion and large numbers of macrophages were recorded in the tonsils, spleen, intestinal lymphatic tissue, Peyer's patches and ileocaecal valve. The presence of typical granulomatous lesions with multinuclear giant cells (MGCs) was also recorded in the lymphatic tissue. Cap antigen was shown to be present in macrophages and less often in lymphocytes.
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Affiliation(s)
- Zsolt Becskei
- 1 Veterinary Specialised Institute ‘Subotica’ Segedinski put 88 24000 Subotica Serbia
| | - Sanja Aleksić-Kovačević
- 2 Belgrade University Department of Pathology, Faculty of Veterinary Medicine Belgrade Serbia
| | - Miklós Rusvai
- 3 Szent István University Department of Pathology and Forensic Veterinary Medicine, Faculty of Veterinary Science István u. 2 H-1078 Budapest Hungary
| | - Gyula Balka
- 3 Szent István University Department of Pathology and Forensic Veterinary Medicine, Faculty of Veterinary Science István u. 2 H-1078 Budapest Hungary
| | - Csaba Jakab
- 3 Szent István University Department of Pathology and Forensic Veterinary Medicine, Faculty of Veterinary Science István u. 2 H-1078 Budapest Hungary
| | - Tamaš Petrović
- 4 Scientific Veterinary Institute ‘Novi Sad’ Novi Sad Serbia
| | - Milijana Knežević
- 2 Belgrade University Department of Pathology, Faculty of Veterinary Medicine Belgrade Serbia
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6
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Balka G, Hornyák A, Dán A, Ladinig A, Biksi I, Rusvai M. PriProET based melting point analyses on PRRSV positive field samples. Mol Cell Probes 2010; 24:411-4. [PMID: 20713151 DOI: 10.1016/j.mcp.2010.08.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2010] [Revised: 07/28/2010] [Accepted: 08/04/2010] [Indexed: 11/19/2022]
Abstract
A one-step real time RT-PCR method has previously been developed for the simultaneous detection of both genotypes of porcine reproductive and respiratory syndrome virus (PRRSV). For further evaluation of the assay and a detailed characterization of the probe binding sites a collection of 24 PRRSV positive field samples from Hungary, Serbia, Austria, a highly pathogenic strain from Bhutan and commercially available MLV vaccine strains were collected and sequenced from the terminal part of ORF6 to the 3' end UTR. The regions that were targeted by the probe were analyzed in detail, and their sequences were compared to that of the probe. Each sample showed a positive result with the PriProET assay, and the samples that showed nucleotide mismatches on the probe binding region had shifted melting points compared to the perfectly matching Lelystad strain. Based on the melting temperatures the strains were classified into 8 groups ranging from 62.4°C to 75.5°C. The samples with the lowest melting temperatures were Type I strains which had less mismatches on the probe binding site than Type II strains. However, these mutations were closer to the 3' end of the probe. It can be speculated that mismatches near the 5' end of the probe had lower influence on the melting temperature.
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Affiliation(s)
- Gyula Balka
- Department of Pathology and Forensic Veterinary Medicine, Faculty of Veterinary Science, Szent István University, István u. 2, H-1078 Budapest, Hungary.
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7
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Malik P, Pálfi V, Bálint A. Development of a new primer-probe energy transfer method for the differentiation of neuropathogenic and non-neuropathogenic strains of equine herpesvirus-1. J Virol Methods 2010; 169:425-7. [PMID: 20709107 DOI: 10.1016/j.jviromet.2010.08.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2010] [Revised: 08/03/2010] [Accepted: 08/05/2010] [Indexed: 11/26/2022]
Abstract
Equine herpesvirus-1 (EHV-1) is a major pathogen of horses with worldwide distribution that can cause various clinical signs ranged from mild respiratory disease to neurological symptoms. Comparison of neuropathogenic and non-neuropathogenic EHV-1 strains revealed that a single non-synonymous nucleotide substitution (A/G2254) in the ORF30 region is associated with the altered functions of the viral DNA polymerase and therefore the neuropathogenicity of EHV-1 virus strains. The aim of the present study was the development of a new differentiation method of this particular single nucleotide polymorphism on the basis of the primer-probe energy transfer (PriProET) technique that has been successfully applied for the detection and classification of various DNA and RNA viruses. The results of melting temperature analysis showed an exact correlation with the sequence variations of the targeted region of ORF30, and the two genotypes (A/G2254) could be easily identified by the different peaks of melting temperatures. The new method is simple, fast, specific and robust as well as more flexible than the previous tests.
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Affiliation(s)
- Péter Malik
- Department of Virology, Central Agricultural Office, Veterinary Diagnostic Directorate, Tábornok u. 2, H-1149 Budapest, Hungary.
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Leblanc N, Rasmussen TB, Fernández J, Sailleau C, Rasmussen LD, Uttenthal A, Zientara S, Belák S, Hakhverdyan M. Development of a real-time RT-PCR assay based on primer-probe energy transfer for the detection of all serotypes of bluetongue virus. J Virol Methods 2010; 167:165-71. [PMID: 20380853 DOI: 10.1016/j.jviromet.2010.03.032] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2008] [Revised: 03/25/2010] [Accepted: 03/29/2010] [Indexed: 11/24/2022]
Abstract
A real-time RT-PCR assay based on the primer-probe energy transfer (PriProET) was developed to detect all 24 serotypes of bluetongue virus (BTV). BTV causes serious disease, primarily in sheep, but in other ruminants as well. A distinguishing characteristic of the assay is its tolerance toward mutations in the probe region. Furthermore, melting curve analysis following immediately PCR confirms specific probe hybridization and can reveal mutations in the probe region by showing a difference in the melting point. The assay sensitivity was in the range of 10-100 target copies and the specificity tests showed no positive results for heterologous pathogens. The assay was tested on clinical samples from BTV 8 outbreaks in Sweden and Denmark in 2008. The lowest detection limit for that serotype, determined with PCR standards, was 57 genome copies. The assay sensitivity for some other serotypes that circulate currently in Europe was also determined. BTV 2, 4, 9 and 16 were tested on available cell culture samples and the detection limits were 109, 12, 13 and 24 copies, respectively. This assay provides an important tool for early and rapid detection of a wide range of BTV strains, including emerging strains.
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Affiliation(s)
- N Leblanc
- Joint Research and Development Division, Department of Virology, the National Veterinary Institute, Uppsala, Sweden.
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