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Guarneri F, Romeo C, Scali F, Zoppi S, Formenti N, Maisano AM, Catania S, Gottschalk M, Alborali GL. Serotype diversity and antimicrobial susceptibility profiles of Actinobacillus pleuropneumoniae isolated in Italian pig farms from 2015 to 2022. Vet Res 2024; 55:48. [PMID: 38594744 PMCID: PMC11005290 DOI: 10.1186/s13567-024-01305-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 03/21/2024] [Indexed: 04/11/2024] Open
Abstract
Actinobacillus pleuropneumoniae (APP) is a bacterium frequently associated with porcine pleuropneumonia. The acute form of the disease is highly contagious and often fatal, resulting in significant economic losses for pig farmers. Serotype diversity and antimicrobial resistance (AMR) of APP strains circulating in north Italian farms from 2015 to 2022 were evaluated retrospectively to investigate APP epidemiology in the area. A total of 572 strains isolated from outbreaks occurring in 337 different swine farms were analysed. The majority of isolates belonged to serotypes 9/11 (39.2%) and 2 (28.1%) and serotype diversity increased during the study period, up to nine different serotypes isolated in 2022. The most common resistances were against tetracycline (53% of isolates) and ampicillin (33%), followed by enrofloxacin, florfenicol and trimethoprim/sulfamethoxazole (23% each). Multidrug resistance (MDR) was common, with a third of isolates showing resistance to more than three antimicrobial classes. Resistance to the different classes and MDR varied significantly depending on the serotype. In particular, the widespread serotype 9/11 was strongly associated with florfenicol and enrofloxacin resistance and showed the highest proportion of MDR isolates. Serotype 5, although less common, showed instead a concerning proportion of trimethoprim/sulfamethoxazole resistance. Our results highlight how the typing of circulating serotypes and the analysis of their antimicrobial susceptibility profile are crucial to effectively manage APP infection and improve antimicrobial stewardship.
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Affiliation(s)
- Flavia Guarneri
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Brescia, Italy
| | - Claudia Romeo
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Brescia, Italy.
- Globe Institute, University of Copenhagen, Copenhagen, Denmark.
| | - Federico Scali
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Brescia, Italy
| | - Simona Zoppi
- Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle D'Aosta, Turin, Italy
| | - Nicoletta Formenti
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Brescia, Italy
| | - Antonio Marco Maisano
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Brescia, Italy
| | | | - Marcelo Gottschalk
- Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada
| | - G Loris Alborali
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Brescia, Italy
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2
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To H, Maldonado J, Tsutsumi N, Gottschalk M, Frey J, Nagai S. Characterization of Actinobacillus pleuropneumoniae biovar 2 isolates reportedly reacted with the serovar 4 antiserum, and development of a multiplex PCR for O-antigen typing. Vet Microbiol 2024; 291:110030. [PMID: 38428226 DOI: 10.1016/j.vetmic.2024.110030] [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: 12/08/2023] [Revised: 02/14/2024] [Accepted: 02/20/2024] [Indexed: 03/03/2024]
Abstract
We have analyzed the capsule (CPS) and the lipopolysaccharide O-Antigen (O-Ag) biosynthesis loci of twelve Spanish field isolates of Actinobacillus pleuropneumoniae biovar 2, eleven of them previously typed serologically as serovar 4 and one non-typable (NT) (Maldonado et al., 2009, 2011). These isolates have the common core genes of the type I CPS locus, sharing >98% identity with those of serovar 2. However, the former possesses the O-Ag locus as serovar 4, and the latter possesses the O-Ag locus as serovar 7. The main difference found between the CPS loci of the 11 isolates and that of serovar 2 reference strain S1536 are two deletions, one of an 8 bp sequence upstream of the coding sequence and one of 111 bp sequence at the 5' end of the cps2G gene. The deletion mutations mentioned lead to a defect in the production of CPS in these isolates, which contributed to their previous mis-identification. In order to complement the serotyping of A. pleuropneumoniae in diagnostics and epidemiology, we have developed a multiplex PCR for the comprehensive O-Ag typing of all A. pleuropneumoniae isolates.
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Affiliation(s)
- Ho To
- Nippon Institute for Biological Science, Tokyo, Japan; Faculty of Agriculture and Aquaculture, University of Cuu Long, Vinh Long, Viet Nam.
| | - Jaime Maldonado
- Diagnostic Laboratory, Laboratorios HIPRA S.A., Paratge Arbusset s/n, Girona 17170, Spain
| | | | - Marcelo Gottschalk
- Groupe de Recherche sur les Maladies Infectieuses en Production Animale, Faculty of Veterinary Medicine, University of Montreal, Québec, Canada
| | - Joachim Frey
- Vetsuisse Faculty, University of Bern, Bern 3012, Switzerland
| | - Shinya Nagai
- Nippon Institute for Biological Science, Tokyo, Japan
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Kuchiishi SS, Ramos Prigol S, Bresolin E, Fernandes Lenhard B, Pissetti C, García-Iglesias MJ, Gutiérrez-Martín CB, Martínez-Martínez S, Kreutz LC, Frandoloso R. Brazilian Clinical Strains of Actinobacillus pleuropneumoniae and Pasteurella multocida: Capsular Diversity, Antimicrobial Susceptibility ( In Vitro) and Proof of Concept for Prevention of Natural Colonization by Multi-Doses Protocol of Tildipirosin. Antibiotics (Basel) 2023; 12:1658. [PMID: 38136692 PMCID: PMC10740920 DOI: 10.3390/antibiotics12121658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Revised: 11/08/2023] [Accepted: 11/10/2023] [Indexed: 12/24/2023] Open
Abstract
One hundred Actinobacillus pleuropneumoniae (App) and sixty Pasteurella multocida subsp. multocida serogroup A (PmA) isolates were recovered from porcine pneumonic lungs collected from eight central or southern states of Brazil between 2014 and 2018 (App) or between 2017 and 2021 (PmA). A. pleuropneumoniae clinical isolates were typed by multiplex PCR and the most prevalent serovars were 8, 7 and 5 (43, 25% and 18%, respectively). In addition, three virulence genes were assessed in P. multocida isolates, all being positive to capA (PmA) and kmt1 genes, all negative to capD and toxA, and most of them (85%) negative to pfhA gene. The susceptibility of both pathogens to tildipirosin was investigated using a broth microdilution assay. The percentage of isolates susceptible to tildipirosin was 95% for App and 73.3% for PmA. The MIC50 values were 0.25 and 1 μg/mL and the MIC90 values were 4 and >64 μg/mL for App and PmA, respectively. Finally, a multiple-dose protocol of tildipirosin was tested in suckling piglets on a farm endemic for both pathogens. Tildipirosin was able to prevent the natural colonization of the tonsils by App and PmA and significantly (p < 0.0001) reduced the burden of Glaesserella parasuis in this tissue. In summary, our results demonstrate that: (i) tildipirosin can be included in the list of antibiotics to control outbreaks of lung disease caused by App regardless of the capsular type, and (ii) in the case of clinical strains of App and PmA that are sensitive to tildipirosin based on susceptibility testing, the use of this antibiotic in eradication programs for A. pleuropneumoniae and P. multocida can be strongly recommended.
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Affiliation(s)
- Suzana Satomi Kuchiishi
- Laboratory of Microbiology and Advanced Immunology, Faculty of Agronomy and Veterinary Medicine, University of Passo Fundo, Passo Fundo 99052-900, Brazil; (S.S.K.); (E.B.); (B.F.L.); (L.C.K.)
- Centro de Diagnóstico de Sanidade Animal—CEDISA, Concórdia 89727-000, Brazil;
| | | | - Eduarda Bresolin
- Laboratory of Microbiology and Advanced Immunology, Faculty of Agronomy and Veterinary Medicine, University of Passo Fundo, Passo Fundo 99052-900, Brazil; (S.S.K.); (E.B.); (B.F.L.); (L.C.K.)
- AFK Imunotech, Passo Fundo 99052-900, Brazil;
| | - Bianca Fernandes Lenhard
- Laboratory of Microbiology and Advanced Immunology, Faculty of Agronomy and Veterinary Medicine, University of Passo Fundo, Passo Fundo 99052-900, Brazil; (S.S.K.); (E.B.); (B.F.L.); (L.C.K.)
| | - Caroline Pissetti
- Centro de Diagnóstico de Sanidade Animal—CEDISA, Concórdia 89727-000, Brazil;
| | - María-José García-Iglesias
- Animal Health Department, Faculty of Veterinary Medicine, University of León, 24007 León, Spain; (M.-J.G.-I.); (C.-B.G.-M.); (S.M.-M.)
| | - César-Bernardo Gutiérrez-Martín
- Animal Health Department, Faculty of Veterinary Medicine, University of León, 24007 León, Spain; (M.-J.G.-I.); (C.-B.G.-M.); (S.M.-M.)
| | - Sonia Martínez-Martínez
- Animal Health Department, Faculty of Veterinary Medicine, University of León, 24007 León, Spain; (M.-J.G.-I.); (C.-B.G.-M.); (S.M.-M.)
| | - Luiz Carlos Kreutz
- Laboratory of Microbiology and Advanced Immunology, Faculty of Agronomy and Veterinary Medicine, University of Passo Fundo, Passo Fundo 99052-900, Brazil; (S.S.K.); (E.B.); (B.F.L.); (L.C.K.)
| | - Rafael Frandoloso
- Laboratory of Microbiology and Advanced Immunology, Faculty of Agronomy and Veterinary Medicine, University of Passo Fundo, Passo Fundo 99052-900, Brazil; (S.S.K.); (E.B.); (B.F.L.); (L.C.K.)
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To H, Tsutsumi N, Ito S, Gottschalk M, Nagai S. Characterization of nonencapsulated Actinobacillus pleuropneumoniae serovar K12:O3 isolates. J Vet Diagn Invest 2023; 35:766-771. [PMID: 37542385 PMCID: PMC10621555 DOI: 10.1177/10406387231190875] [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] [Indexed: 08/06/2023] Open
Abstract
Three Actinobacillus pleuropneumoniae isolates from clinical cases of porcine pleuropneumonia were positive by capsular serovar 12-specific PCR assay, but not reactive to antiserum prepared against serovar 12 using the rapid slide agglutination (RSA) test. The isolates were positive for apxIICA, apxIIICA, apxIBD, apxIIIBD, and apxIVA in the PCR toxin gene assay, which is the profile seen in serovars 2, 4, 6, 8, and 15, and reacted with antisera against serovars 3, 6, 8, 15, and 17. Nucleotide sequence analysis revealed that genes involved in the biosynthesis of capsular polysaccharide of the 3 isolates were identical or nearly identical to those of serovar 12. However, genes involved in the biosynthesis of O-polysaccharide of the 3 isolates were highly similar to those of reference strains of serovars 3, 6, 8, 15, 17, and 19. In agreement with results from the RSA test, transmission electron microscopic analysis confirmed the absence of detectable capsular material in the 3 isolates. The existence of nonencapsulated A. pleuropneumoniae serovar K12:O3 would hamper precise serodetection.
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Affiliation(s)
- Ho To
- Nippon Institute for Biological Science, Tokyo, Japan
- Faculty of Agriculture and Aquaculture, University of Cuu Long, Vinh Long, Vietnam
| | | | - Soma Ito
- Nippon Institute for Biological Science, Tokyo, Japan
| | - Marcelo Gottschalk
- Faculty of Veterinary Medicine, University of Montreal, St-Hyacinthe, Quebec, Canada
| | - Shinya Nagai
- Nippon Institute for Biological Science, Tokyo, Japan
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Donà V, Ramette A, Perreten V. Comparative genomics of 26 complete circular genomes of 18 different serotypes of Actinobacillus pleuropneumoniae. Microb Genom 2022; 8. [PMID: 35196217 PMCID: PMC8942016 DOI: 10.1099/mgen.0.000776] [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] [Indexed: 11/23/2022] Open
Abstract
Actinobacillus pleuropneumoniae is a Gram-negative, rod-shaped bacterium of the family Pasteurellaceae causing pig pleuropneumonia associated with great economic losses worldwide. Nineteen serotypes with distinctive lipopolysaccharide (LPS) and capsular (CPS) compositions have been described so far, yet complete circular genomes are publicly available only for the reference strains of serotypes 1, 4 and 5b, and for field strains of serotypes 1, 3, 7 and 8. We aimed to complete this picture by sequencing the reference strains of 17 different serotypes with the MinION sequencer (Oxford Nanopore Technologies, ONT) and on an Illumina HiSeq (Illumina) platform. We also included two field isolates of serotypes 2 and 3 that were PacBio- and MinION-sequenced, respectively. Genome assemblies were performed following two different strategies, i.e. PacBio- or ONT-only de novo assemblies polished with Illumina reads or a hybrid assembly by directly combining ONT and Illumina reads. Both methods proved successful in obtaining accurate circular genomes with comparable qualities. blast-based genome comparisons and core-genome phylogeny based on core genes, SNP typing and multi-locus sequence typing (cgMLST) of the 26 circular genomes indicated well-conserved genomes across the 18 different serotypes, differing mainly in phage insertions, and CPS, LPS and RTX-toxin clusters, which, consistently, encode serotype-specific antigens. We also identified small antibiotic resistance plasmids, and complete subtype I-F and subtype II-C CRISPR-Cas systems. Of note, highly similar clusters encoding all those serotype-specific traits were also found in other pathogenic and commensal Actinobacillus species. Taken together with the presence of transposable elements surrounding these loci, we speculate a dynamic intra- and interspecies exchange of such virulence-related factors by horizontal gene transfer. In conclusion, our comprehensive genomics analysis provides useful information for diagnostic test and vaccine development, but also for whole-genome-based epidemiological studies, as well as for the surveillance of the evolution of antibiotic resistance and virulence genes in A. pleuropneumoniae.
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Affiliation(s)
- Valentina Donà
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Alban Ramette
- Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Vincent Perreten
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
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6
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Abstract
Actinobacillus pleuropneumoniae causes porcine pleuropneumonia, an important disease in the pig industry. Accurate and sensitive diagnostics such as DNA-based diagnostics are essential for preventing or responding to an outbreak. The specificity of DNA-based diagnostics depends on species-specific markers. Previously, an insertion element was found within an A. pleuropneumoniae-specific gene commonly used for A. pleuropneumoniae detection, prompting the need for additional species-specific markers. Herein, 12 marker candidates highly conserved (99 - 100% identity) among 34 A. pleuropneumoniae genomes (covering 13 serovars) were identified to be A. pleuropneumoniae-specific in silico, as these sequences are distinct from 30 genomes of 13 other Actinobacillus and problematic [Actinobacillus] species and more than 1700 genomes of other bacteria in the Pasteurellaceae family. Five marker candidates are within the apxIVA gene, a known A. pleuropneumoniae-specific gene, validating our in silico marker discovery method. Seven other A. pleuropneumoniae-specific marker candidates within the eamA, nusG, sppA, xerD, ybbN, ycfL, and ychJ genes were validated by polymerase chain reaction (PCR) to be specific to 129 isolates of A. pleuropneumoniae (covering all 19 serovars), but not to four closely related Actinobacillus species, four [Actinobacillus] species, or seven other bacterial species. This is the first study to identify A. pleuropneumoniae-specific markers through genome mining. Seven novel A. pleuropneumoniae-specific DNA markers were identified by a combination of in silico and molecular methods and can serve as additional or alternative targets for A. pleuropneumoniae diagnostics, potentially leading to better control of the disease. IMPORTANCE Species-specific markers are crucial for infectious disease diagnostics. Mutations within a marker sequence can lead to false-negative results, inappropriate treatment, and economic loss. The availability of several species-specific markers is therefore desirable. In this study, 12 DNA markers specific to A. pleuropneumoniae, a pig pathogen, were simultaneously identified. Five marker candidates are within a known A. pleuropneumoniae-specific gene. Seven novel markers can be used as additional targets in DNA-based diagnostics, which in turn can expedite disease diagnosis, assist farm management, and lead to better animal health and food security. The marker discovery strategy outlined herein requires less time, effort, and cost, and results in more markers compared with conventional methods. Identification of species-specific markers of other pathogens and corresponding infectious disease diagnostics are possible, conceivably improving health care and the economy.
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Proposal of a subtype of serovar 4, K4b:O3, of Actinobacillus pleuropneumoniae based on serological and genotypic analysis. Vet Microbiol 2021; 263:109279. [PMID: 34798366 DOI: 10.1016/j.vetmic.2021.109279] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 11/02/2021] [Accepted: 11/08/2021] [Indexed: 11/22/2022]
Abstract
The aim of this study was to investigate an isolate of Actinobacillus pleuropneumoniae, named 14-760, which was serologically not classifiable among the recognised serovars of A. pleuropneumoniae. It reacted with the antisera raised against serovars 3, 6, 8, 15 and 17 in the agar gel precipitation (AGP) test, and was positive in the capsular serovar 4-specific PCR (cps4B PCR) assay. The isolate contains a type II capsule locus similar to serovar 4 but with variations in the length of four intergeneric regions (modF-cpxA, cpxD-cpsA, cpsC-a 114 bp orf, and lysA-ydeN), and three gene sequences (modF, cpsC and ydeN). The main difference found between the K4 and K4b cps genes is the additional 35 AAs found in type 4b due to a 4 bp insert in cps4bC. The LPS O-Ag locus is highly similar to that of reference strains of serovars 3, 6, 8, 15, 17 and 19. Isolate 14-760 is biovar 1 and contains solely the structural genes required for toxin ApxII production (apxIICA), and the type I secretion system (apxIBD) for the export of ApxII. Antiserum against isolate 14-760 adsorbed with antigen prepared from serovars 8, 15 or 17 reference strains remained reactive with isolate 14-760, but not with antigens prepared from serovars 1-18. Taken together, our results indicate the existence of a subtype of A. pleuropneumoniae, serovar 4, that we called "K4b:O3″, and we propose isolate 14-760 as the reference strain.
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Sun X, Blackall PJ, Daniel P, Chandra K, Jenkin S, Turni C. An improved multiplex PCR for Actinobacillus pleuropneumoniae, Glaesserella australis and Pasteurella multocida. J Microbiol Methods 2021; 191:106360. [PMID: 34740721 DOI: 10.1016/j.mimet.2021.106360] [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: 08/31/2021] [Revised: 10/07/2021] [Accepted: 10/27/2021] [Indexed: 10/19/2022]
Abstract
Glaesserella australis, a newly described bacterial species, has been isolated from pig lungs that displayed lesions very similar to those caused by Actinobacillus pleuropneumoniae, prompting the need for a validated diagnostic tool. In this work, we have altered a multiplex PCR used for the identification of cultures of G. australis, A. pleuropneumoniae and Pasteurella multocida to be more sensitive and then evaluated the use of the altered diagnostic tool on cultures and directly on tissues. The altered multiplex PCR was validated using 47 related species, both type/reference strains and field isolates. The sensitivity was assessed by serial dilutions and used a mixture of target bacteria in different concentrations. Further, 166 lung samples from 54 farms from four Australian States were used to validate the ability of the multiplex PCR to detect bacteria in lung swabs. The multiplex PCR was specific for the three target species. The assay could detect a minimum of 40 colony forming units (CFU) of G. australis, 786 CFU of A. pleuropneumoniae and 238 CFU of P. multocida. The multiplex PCR yielded more positives than coventional bacteriological examination. From a total of 166 lung samples, 51.9%, 51.9% and 5.6% of farms were PCR positive for P. multocida, A. pleuropneumoniae and G. australis, respectively. The results suggested that the new multiplex PCR was specific, sensitive and out performed traditional culture. The prevalence of G. australis was not very high, but it was the dominant pathogen in infected pigs.
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Affiliation(s)
- Xiaochen Sun
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, Queensland 4067, Australia
| | - P J Blackall
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, Queensland 4067, Australia
| | - Patrick Daniel
- Pig Services Centre, Agriculture, Food and Fibre Division, Department of Jobs, Precincts and Regions, Epsom, Victoria 3551, Australia
| | - Kerri Chandra
- Department of Agriculture and Fisheries, Ecosciences Precinct, Dutton Park, Queensland 4102, Australia
| | - Sarah Jenkin
- Apiam Animal Health, Bendigo, Victoria 3550, Australia
| | - Conny Turni
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, Queensland 4067, Australia.
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Stringer OW, Bossé JT, Lacouture S, Gottschalk M, Fodor L, Angen Ø, Velazquez E, Penny P, Lei L, Langford PR, Li Y. Rapid Detection and Typing of Actinobacillus pleuropneumoniae Serovars Directly From Clinical Samples: Combining FTA ® Card Technology With Multiplex PCR. Front Vet Sci 2021; 8:728660. [PMID: 34447805 PMCID: PMC8382971 DOI: 10.3389/fvets.2021.728660] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 07/12/2021] [Indexed: 11/13/2022] Open
Abstract
Actinobacillus pleuropneumoniae (APP), the causative agent of porcine pleuropneumonia, is highly contagious and responsible for high morbidity, mortality, and economic losses in the swine industry worldwide, but quick serotyping and diagnosis are still not widely available. In this study, we sought to validate the use of Whatman FTA® cards for collection and processing of A. pleuropneumoniae isolates, or porcine lung tissue samples, for direct use in diagnostic multiplex PCRs. We have optimized the processing of 3-mm discs punched from FTA® cards loaded with cultured A. pleuropneumoniae, or imprinted on lesioned regions of lung tissue, with only three distilled water washes before addition into our APP-multiplex PCR (mPCR) assay for rapid, low-cost identification and serotyping. DNA captured on FTA® cards generated the same diagnostic PCR results as DNA extracted using commercial kits for 85 A. pleuropneumoniae clinical isolate cultures and 22 lung samples. Additionally, bacterial DNA bound to FTA® cards was detectable by PCR after 6 months of storage at 37°C. This study provides simple, efficient, rapid, and practical sample processing for detection and molecular serotyping of A. pleuropneumoniae.
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Affiliation(s)
- Oliver W. Stringer
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Janine T. Bossé
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Sonia Lacouture
- Groupe de Recherche sur les Maladies Infectieuses en Production Animale, Faculty of Veterinary Medicine, University of Montreal, Montreal, QC, Canada
| | - Marcelo Gottschalk
- Groupe de Recherche sur les Maladies Infectieuses en Production Animale, Faculty of Veterinary Medicine, University of Montreal, Montreal, QC, Canada
| | - László Fodor
- Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, Budapest, Hungary
| | - Øystein Angen
- Department of Microbiology and Infection Control, Statens Serum Institut, Copenhagen, Denmark
| | | | - Paul Penny
- Ceva Animal Health Ltd., Amersham, United Kingdom
| | - Liancheng Lei
- College of Veterinary Medicine, Jilin University, Changchun, China
| | - Paul R. Langford
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Yanwen Li
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, United Kingdom
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Aida V, Pliasas VC, Neasham PJ, North JF, McWhorter KL, Glover SR, Kyriakis CS. Novel Vaccine Technologies in Veterinary Medicine: A Herald to Human Medicine Vaccines. Front Vet Sci 2021; 8:654289. [PMID: 33937377 PMCID: PMC8083957 DOI: 10.3389/fvets.2021.654289] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 03/17/2021] [Indexed: 01/10/2023] Open
Abstract
The success of inactivated and live-attenuated vaccines has enhanced livestock productivity, promoted food security, and attenuated the morbidity and mortality of several human, animal, and zoonotic diseases. However, these traditional vaccine technologies are not without fault. The efficacy of inactivated vaccines can be suboptimal with particular pathogens and safety concerns arise with live-attenuated vaccines. Additionally, the rate of emerging infectious diseases continues to increase and with that the need to quickly deploy new vaccines. Unfortunately, first generation vaccines are not conducive to such urgencies. Within the last three decades, veterinary medicine has spearheaded the advancement in novel vaccine development to circumvent several of the flaws associated with classical vaccines. These third generation vaccines, including DNA, RNA and recombinant viral-vector vaccines, induce both humoral and cellular immune response, are economically manufactured, safe to use, and can be utilized to differentiate infected from vaccinated animals. The present article offers a review of commercially available novel vaccine technologies currently utilized in companion animal, food animal, and wildlife disease control.
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Affiliation(s)
- Virginia Aida
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
- Emory-University of Georgia (UGA) Center of Excellence for Influenza Research and Surveillance (CEIRS), Auburn, AL, United States
| | - Vasilis C. Pliasas
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
- Emory-University of Georgia (UGA) Center of Excellence for Influenza Research and Surveillance (CEIRS), Auburn, AL, United States
| | - Peter J. Neasham
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
- Emory-University of Georgia (UGA) Center of Excellence for Influenza Research and Surveillance (CEIRS), Auburn, AL, United States
| | - J. Fletcher North
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
- Emory-University of Georgia (UGA) Center of Excellence for Influenza Research and Surveillance (CEIRS), Auburn, AL, United States
| | - Kirklin L. McWhorter
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
- Department of Chemistry, Emory University, Atlanta, GA, United States
| | - Sheniqua R. Glover
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
- Emory-University of Georgia (UGA) Center of Excellence for Influenza Research and Surveillance (CEIRS), Auburn, AL, United States
| | - Constantinos S. Kyriakis
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
- Emory-University of Georgia (UGA) Center of Excellence for Influenza Research and Surveillance (CEIRS), Auburn, AL, United States
- Center for Vaccines and Immunology, University of Georgia, Athens, GA, United States
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Stringer OW, Bossé JT, Lacouture S, Gottschalk M, Fodor L, Angen Ø, Velazquez E, Penny P, Lei L, Langford PR, Li Y. Proposal of Actinobacillus pleuropneumoniae serovar 19, and reformulation of previous multiplex PCRs for capsule-specific typing of all known serovars. Vet Microbiol 2021; 255:109021. [PMID: 33667982 DOI: 10.1016/j.vetmic.2021.109021] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 02/22/2021] [Indexed: 02/01/2023]
Abstract
Two serologically and molecularly non-typeable isolates of the porcine lung pathogen Actinobacillus pleuropneumoniae have been identified from diseased swine in two different continents. Genome sequencing was carried out to identify their diagnostically relevant genotypes. Both isolates are biovar 1 and encode genes for production of ApxIV and ApxII (apxIICA structural genes, and apxIBD export genes). They both possess the same novel type II capsule locus (most similar to serovar 1, but with two capsule genes not previously found in A. pleuropneumoniae) but differ in their O-Ag loci. Strain 7213384-1 from Denmark, which we propose as the reference strain for serovar 19, has a serogroup 3/6/8/15 O-Ag locus; the Canadian isolate A08-013 has a serogroup 4/7 O-Ag locus. We have expanded the second of our two previously described A. pleuropneumoniae mPCRs to include capsule gene-specific primers for definitive detection of serovars 13-14 and 16-19.
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Affiliation(s)
- Oliver W Stringer
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, UK
| | - Janine T Bossé
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, UK.
| | - Sonia Lacouture
- Groupe de Recherche sur les Maladies Infectieuses du Porc, Faculté de Médecine Vétérinaire, Université de Montréal, Québec, Canada
| | - Marcelo Gottschalk
- Groupe de Recherche sur les Maladies Infectieuses du Porc, Faculté de Médecine Vétérinaire, Université de Montréal, Québec, Canada
| | - László Fodor
- Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, Budapest, Hungary
| | - Øystein Angen
- Department of Microbiology and Infection Control, Statens Serum Institut, Copenhagen, Denmark
| | | | | | - Liancheng Lei
- College of Veterinary Medicine, Jilin University, Changchun, PR China
| | - Paul R Langford
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, UK.
| | - Yanwen Li
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, UK
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12
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Crispim JS, da Silva TF, Sanches NM, da Silva GC, Pereira MF, Rossi CC, Li Y, Terra VS, Vohra P, Wren BW, Langford PR, Bossé JT, Bazzolli DMS. Serovar-dependent differences in Hfq-regulated phenotypes inActinobacillus pleuropneumoniae. Pathog Dis 2020; 78:5936557. [DOI: 10.1093/femspd/ftaa066] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 10/21/2020] [Indexed: 12/28/2022] Open
Abstract
ABSTRACTThe RNA chaperone Hfq regulates diverse processes in numerous bacteria. In this study, we compared phenotypes (growth rate, adherence, response to different stress conditions and virulence in Galleria mellonella) of wild-type (WT) and isogenic hfq mutants of three serovars (1, 8 and 15) of the porcine pathogen Actinobacillus pleuropneumoniae. Similar growth in rich broth was seen for all strains except Ap1∆hfq, which showed slightly reduced growth throughout the 24 h time course, and the complemented Ap8∆hfqC mutant had a prolonged lag phase. Differences were seen between the three serovar WT strains regarding adherence, stress response and virulence in G. mellonella, and deletion of hfq affected some, but not all of these phenotypes, depending on serovar. Complementation by expression of cloned hfq from an endogenous promoter only restored some WT phenotypes, indicating that complex regulatory networks may be involved, and that levels of Hfq may be as important as presence/absence of the protein regarding its contribution to gene regulation. Our results support that Hfq is a pleiotropic global regulator in A. pleuropneumoniae, but serovar-related differences exist. These results highlight the importance of testing multiple strains/serovars within a given species when determining contributions of global regulators, such as Hfq, to expression of complex phenotypes.
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Affiliation(s)
- Josicelli Souza Crispim
- Laboratório de Genética Molecular de Bactérias, Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária – BIOAGRO, Universidade Federal de Viçosa, Viçosa, 36570–900, Brazil
| | - Thyara Ferreira da Silva
- Laboratório de Genética Molecular de Bactérias, Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária – BIOAGRO, Universidade Federal de Viçosa, Viçosa, 36570–900, Brazil
| | - Newton Moreno Sanches
- Laboratório de Genética Molecular de Bactérias, Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária – BIOAGRO, Universidade Federal de Viçosa, Viçosa, 36570–900, Brazil
| | - Giarlã Cunha da Silva
- Laboratório de Genética Molecular de Bactérias, Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária – BIOAGRO, Universidade Federal de Viçosa, Viçosa, 36570–900, Brazil
| | - Monalessa Fábia Pereira
- Laboratório de Genética Molecular de Bactérias, Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária – BIOAGRO, Universidade Federal de Viçosa, Viçosa, 36570–900, Brazil
| | - Ciro César Rossi
- Laboratório de Genética Molecular de Bactérias, Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária – BIOAGRO, Universidade Federal de Viçosa, Viçosa, 36570–900, Brazil
| | - Yanwen Li
- Section of Paediatric Infectious Disease, Imperial College London, St Mary's Campus, London W2 1PG, UK
| | - Vanessa Sofia Terra
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Prerna Vohra
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Brendan W Wren
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Paul R Langford
- Section of Paediatric Infectious Disease, Imperial College London, St Mary's Campus, London W2 1PG, UK
| | - Janine T Bossé
- Section of Paediatric Infectious Disease, Imperial College London, St Mary's Campus, London W2 1PG, UK
| | - Denise Mara Soares Bazzolli
- Laboratório de Genética Molecular de Bactérias, Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária – BIOAGRO, Universidade Federal de Viçosa, Viçosa, 36570–900, Brazil
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13
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To H, Teshima K, Kon M, Yasuda S, Akaike Y, Shibuya K, Nagai S, Sasakawa C. Characterization of nontypeable Actinobacillus pleuropneumoniae isolates. J Vet Diagn Invest 2020; 32:581-584. [PMID: 32517629 DOI: 10.1177/1040638720931469] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Two Actinobacillus pleuropneumoniae isolates from clinical cases of porcine pleuropneumonia in Japan were positive in the capsular serovar 15-specific PCR assay, but nontypeable (NT) in the agar gel precipitation (AGP) test. Nucleotide sequence analysis of gene clusters involved in the biosynthesis of capsular polysaccharide (CPS) and lipopolysaccharide O-polysaccharide (O-PS) revealed that both clusters contained transposable element ISApl1 of A. pleuropneumoniae belonging to the IS30 family. Immunoblot analysis revealed that these 2 isolates could not produce O-PS. We conclude that the ISApl1 of A. pleuropneumoniae can interfere in the biosynthesis of both CPS and O-PS.
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Affiliation(s)
- Ho To
- Nippon Institute for Biological Science, Ome, Tokyo, Japan (To, Teshima, Kon, Yasuda, Akaike, Shibuya, Nagai, Sasakawa).,Medical Mycology Research Center, Chiba University, Chiba, Japan (Sasakawa)
| | - Kaho Teshima
- Nippon Institute for Biological Science, Ome, Tokyo, Japan (To, Teshima, Kon, Yasuda, Akaike, Shibuya, Nagai, Sasakawa).,Medical Mycology Research Center, Chiba University, Chiba, Japan (Sasakawa)
| | - Michiha Kon
- Nippon Institute for Biological Science, Ome, Tokyo, Japan (To, Teshima, Kon, Yasuda, Akaike, Shibuya, Nagai, Sasakawa).,Medical Mycology Research Center, Chiba University, Chiba, Japan (Sasakawa)
| | - Saori Yasuda
- Nippon Institute for Biological Science, Ome, Tokyo, Japan (To, Teshima, Kon, Yasuda, Akaike, Shibuya, Nagai, Sasakawa).,Medical Mycology Research Center, Chiba University, Chiba, Japan (Sasakawa)
| | - Yuta Akaike
- Nippon Institute for Biological Science, Ome, Tokyo, Japan (To, Teshima, Kon, Yasuda, Akaike, Shibuya, Nagai, Sasakawa).,Medical Mycology Research Center, Chiba University, Chiba, Japan (Sasakawa)
| | - Kazumoto Shibuya
- Nippon Institute for Biological Science, Ome, Tokyo, Japan (To, Teshima, Kon, Yasuda, Akaike, Shibuya, Nagai, Sasakawa).,Medical Mycology Research Center, Chiba University, Chiba, Japan (Sasakawa)
| | - Shinya Nagai
- Nippon Institute for Biological Science, Ome, Tokyo, Japan (To, Teshima, Kon, Yasuda, Akaike, Shibuya, Nagai, Sasakawa).,Medical Mycology Research Center, Chiba University, Chiba, Japan (Sasakawa)
| | - Chihiro Sasakawa
- Nippon Institute for Biological Science, Ome, Tokyo, Japan (To, Teshima, Kon, Yasuda, Akaike, Shibuya, Nagai, Sasakawa).,Medical Mycology Research Center, Chiba University, Chiba, Japan (Sasakawa)
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Basal-Level Effects of (p)ppGpp in the Absence of Branched-Chain Amino Acids in Actinobacillus pleuropneumoniae. J Bacteriol 2020; 202:JB.00640-19. [PMID: 32015147 DOI: 10.1128/jb.00640-19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 01/24/2020] [Indexed: 12/23/2022] Open
Abstract
The (p)ppGpp-mediated stringent response (SR) is a highly conserved regulatory mechanism in bacterial pathogens, enabling adaptation to adverse environments, and is linked to pathogenesis. Actinobacillus pleuropneumoniae can cause damage to the lungs of pigs, its only known natural host. Pig lungs are known to have a low concentration of free branched-chain amino acids (BCAAs) compared to the level in plasma. We had investigated the role for (p)ppGpp in viability and biofilm formation of A. pleuropneumoniae Now, we sought to determine whether (p)ppGpp was a trigger signal for the SR in A. pleuropneumoniae in the absence of BCAAs. Combining transcriptome and phenotypic analyses of the wild type (WT) and an relA spoT double mutant [which does not produce (p)ppGpp], we found that (p)ppGpp could repress de novo purine biosynthesis and activate antioxidant pathways. There was a positive correlation between GTP and endogenous hydrogen peroxide content. Furthermore, the growth, viability, morphology, and virulence were altered by the inability to produce (p)ppGpp. Genes involved in the biosynthesis of BCAAs were constitutively upregulated, regardless of the existence of BCAAs, without accumulation of (p)ppGpp beyond a basal level. Collectively, our study shows that the absence of BCAAs was not a sufficient signal to trigger the SR in A. pleuropneumoniae (p)ppGpp-mediated regulation in A. pleuropneumoniae is different from that described for the model organism Escherichia coli Further work will establish whether the (p)ppGpp-dependent SR mechanism in A. pleuropneumoniae is conserved among other veterinary pathogens, especially those in the Pasteurellaceae family.IMPORTANCE (p)ppGpp is a key player in reprogramming transcriptomes to respond to nutritional challenges. Here, we present transcriptional and phenotypic differences of A. pleuropneumoniae grown in different chemically defined media in the absence of (p)ppGpp. We show that the deprivation of branched-chain amino acids (BCAAs) does not elicit a change in the basal-level (p)ppGpp, but this level is sufficient to regulate the expression of BCAA biosynthesis. The mechanism found in A. pleuropneumoniae is different from that of the model organism Escherichia coli but similar to that found in some Gram-positive bacteria. This study not only broadens the research scope of (p)ppGpp but also further validates the complexity and multiplicity of (p)ppGpp regulation in microorganisms that occupy different biological niches.
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15
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A competence-regulated toxin-antitoxin system in Haemophilus influenzae. PLoS One 2020; 15:e0217255. [PMID: 31931516 PMCID: PMC6957337 DOI: 10.1371/journal.pone.0217255] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 12/16/2019] [Indexed: 12/28/2022] Open
Abstract
Natural competence allows bacteria to respond to environmental and nutritional cues by taking up free DNA from their surroundings, thus gaining both nutrients and genetic information. In the Gram-negative bacterium Haemophilus influenzae, the genes needed for DNA uptake are induced by the CRP and Sxy transcription factors in response to lack of preferred carbon sources and nucleotide precursors. Here we show that one of these genes, HI0659, encodes the antitoxin of a competence-regulated toxin-antitoxin operon (‘toxTA’), likely acquired by horizontal gene transfer from a Streptococcus species. Deletion of the putative toxin (HI0660) restores uptake to the antitoxin mutant. The full toxTA operon was present in only 17 of the 181 strains we examined; complete deletion was seen in 22 strains and deletions removing parts of the toxin gene in 142 others. In addition to the expected Sxy- and CRP-dependent-competence promoter, HI0659/660 transcript analysis using RNA-seq identified an internal antitoxin-repressed promoter whose transcription starts within toxT and will yield nonfunctional protein. We propose that the most likely effect of unopposed toxin expression is non-specific cleavage of mRNAs and arrest or death of competent cells in the culture. Although the high frequency of toxT and toxTA deletions suggests that this competence-regulated toxin-antitoxin system may be mildly deleterious, it could also facilitate downregulation of protein synthesis and recycling of nucleotides under starvation conditions. Although our analyses were focused on the effects of toxTA, the RNA-seq dataset will be a useful resource for further investigations into competence regulation.
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16
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Immunological and molecular techniques used for determination of serotypes in Pasteurellaceae. J Microbiol Methods 2020. [DOI: 10.1016/bs.mim.2020.01.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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17
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Makrai L, Sárközi R, Fodor L. Carbon source utilisation and evaluation of the Biolog system in the identification of Actinobacillus pleuropneumoniae. Acta Vet Hung 2019; 67:327-337. [PMID: 31549548 DOI: 10.1556/004.2019.034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Sixty-eight Actinobacillus pleuropneumoniae strains were isolated from porcine acute pleuropneumonia cases from different parts of Hungary between 2000 and 2014. A total of 41 isolates were identified as A. pleuropneumoniae bio-type I and 27 strains as biotype II based on cultural, morphological and biochemical characteristics. The aim of this study was to evaluate metabolic fingerprinting in the species-level identification of A. pleuropneumoniae isolates. Utilisation of carbon sources by these field isolates and six reference strains was characterised by the Biolog system (GN2 Microplate, MicroLog3 Version 4.20.05 software). Twenty-nine field strains were correctly identified by the Biolog system as A. pleuropneumoniae, 36 strains as A. lignieresii, two strains as H. paraphrohaemolyticus and one strain as A. equuli after 24 h of incubation. Among the six A. pleuropneumoniae reference strains the Biolog system identified one strain as A. pleuropneumoniae, four as A. lignieresii and one as H. paraphrohaemolyticus. There was no correlation between biotypes and serotypes of A. pleuropneumoniae and the carbon source utilisation pattern and species identification by the Biolog system. our data indicate that the efficacy of the Biolog system used here could be improved by including phenotypes of more A. pleuropneumoniae strains representing a wider geographical occurrence into the database.
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Affiliation(s)
- László Makrai
- 1Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, H-1581 Budapest, P.O. Box 22, Hungary
| | - Rita Sárközi
- 1Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, H-1581 Budapest, P.O. Box 22, Hungary
| | - László Fodor
- 1Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, H-1581 Budapest, P.O. Box 22, Hungary
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18
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Li R, Wang J, Liu L, Zhang R, Hao X, Han Q, Wang J, Yuan W. Direct detection of Actinobacillus pleuropneumoniae in swine lungs and tonsils by real-time recombinase polymerase amplification assay. Mol Cell Probes 2019; 45:14-18. [PMID: 30930280 DOI: 10.1016/j.mcp.2019.03.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 03/26/2019] [Accepted: 03/26/2019] [Indexed: 12/29/2022]
Abstract
Actinobacillus pleuropneumoniae is the etiological agent of swine contagious pleuropneumoniae, which is distributed globally and associated with severe economic losses in the pig rearing industry. In this study, a real-time recombinase polymerase amplification assay (real-time RPA) based on the apxIVA gene was developed to rapid detect A. pleuropneumoniae. Real-time RPA was performed successfully in Genie III at the constant temperature of 39 °C for 20 min. The developed assay was highly specific for A. pleuropneumoniae, and the sensitivity at 95% probability was 536 fg of A. pleuropneumoniae genomic DNA. The real-time RPA for A. pleuropneumoniae was further evaluated on the 112 clinical swine lung and tonsil samples, and 25 (22.3%), 27 (24.1%), and 12 (10.7%) samples were positive for A. pleuropneumoniae by the real-time RPA, real-time PCR and bacterial isolation, respectively. With a real-time PCR as the reference method, the real-time RPA showed a diagnostic specificity of 98.8%, a diagnostic sensitivity of 88.9%, a positive predicative value of 96.0%, a negative predictive value of 96.5%, and a kappa value of 0.900. The above data demonstrated the well potentiality and usefulness of the developed real-time RPA assay in the reliable detection of A. pleuropneumoniae, especially in resource limited settings.
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Affiliation(s)
- Ruiwen Li
- College of Veterinary Medicine, Hebei Agricultural University, Baoding, 071001, China
| | - Jinfeng Wang
- Center of Inspection and Quarantine Technology, Hebei Entry-Exit Inspection and Quarantine Bureau, Shijiazhuang, 050051, China
| | - Libing Liu
- Center of Inspection and Quarantine Technology, Hebei Entry-Exit Inspection and Quarantine Bureau, Shijiazhuang, 050051, China; Hebei Academy of Science and Technology for Inspection and Quarantine, Shijiazhuang, 050051, China
| | - Ruoxi Zhang
- Hebei Animal Disease Control Center, Shijiazhuang, 050050, China
| | - Xuepiao Hao
- College of Veterinary Medicine, Hebei Agricultural University, Baoding, 071001, China
| | - Qingan Han
- Hebei Animal Disease Control Center, Shijiazhuang, 050050, China
| | - Jianchang Wang
- Center of Inspection and Quarantine Technology, Hebei Entry-Exit Inspection and Quarantine Bureau, Shijiazhuang, 050051, China; Hebei Academy of Science and Technology for Inspection and Quarantine, Shijiazhuang, 050051, China.
| | - Wanzhe Yuan
- College of Veterinary Medicine, Hebei Agricultural University, Baoding, 071001, China.
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Passmore IJ, Andrejeva A, Wren BW, Cuccui J. Cytoplasmic glycoengineering of Apx toxin fragments in the development of Actinobacillus pleuropneumoniae glycoconjugate vaccines. BMC Vet Res 2019; 15:6. [PMID: 30606265 PMCID: PMC6318927 DOI: 10.1186/s12917-018-1751-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 12/17/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Actinobacillus pleuropneumoniae is the causative agent of porcine pleuropneumonia and represents a major burden to the livestock industry. Virulence can largely be attributed to the secretion of a series of haemolytic toxins, which are highly immunogenic. A. pleuropneumoniae also encodes a cytoplasmic N-glycosylation system, which involves the modification of high molecular weight adhesins with glucose residues. Central to this process is the soluble N-glycosyl transferase, ngt, which is encoded in an operon with a subsequent glycosyl transferase, agt. Plasmid-borne recombinant expression of these genes in E. coli results in the production of a glucose polymer on peptides containing the appropriate acceptor sequon, NX(S/T). However to date, there is little evidence to suggest that such a glucose polymer is formed on its target peptides in A. pleuropneumoniae. Both the toxins and glycosylation system represent potential targets for the basis of a vaccine against A. pleuropneumoniae infection. RESULTS In this study, we developed cytoplasmic glycoengineering to construct glycoconjugate vaccine candidates composed of soluble toxin fragments modified by glucose. We transferred ngt and agt to the chromosome of Escherichia coli in order to generate a native-like operon for glycoengineering. A single chromosomal copy of ngt and agt resulted in the glucosylation of toxin fragments by a short glycan, rather than a polymer. CONCLUSIONS A vaccine candidate that combines toxin fragment with a conserved glycan offers a novel approach to generating epitopes important for both colonisation and disease progression.
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Affiliation(s)
- Ian J Passmore
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Anna Andrejeva
- Cambridge Centre for Proteomics, Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - Brendan W Wren
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Jon Cuccui
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
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dos Santos LF, Costa Polveiro R, Scatamburlo Moreira T, Pereira Vidigal PM, Chang YF, Scatamburlo Moreira MA. Polymorphism analysis of the apxIA gene of Actinobacillus pleuropneumoniae serovar 5 isolated in swine herds from Brazil. PLoS One 2018; 13:e0208789. [PMID: 30562362 PMCID: PMC6298653 DOI: 10.1371/journal.pone.0208789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 11/26/2018] [Indexed: 11/30/2022] Open
Abstract
The bacterium Actinobacillus pleuropneumoniae is the etiological agent of Contagious Porcine Pleuropneumonia, a disease responsible for economic losses in the swine industry worldwide. A. pleuropneumoniae is capable of producing proteinaceous exotoxins responsible for inducing hemorrhagic lesions, one of which is ApxI. Few studies have conducted an in-depth evaluation of polymorphisms of the nucleotides that make up the ApxI toxin gene. Here we analyze the polymorphisms of the apxIA gene region of A. pleuropneumoniae serovar 5 isolated from swine in different regions in Brazil and report the results of molecular sequencing and phylogenetic analysis. Analysis of the apxIA gene in 60 isolates revealed the presence of genetic diversity and variability. The polymorphisms in the nucleotide sequences determined the grouping of the Brazilian sequences and five more sequences from the GenBank database into 14 different haplotypes, which formed three main groups and revealed the presence of mutations in the nucleotide sequences. The estimation of selection pressures suggests the occurrence of genetic variations by positive selective pressure on A. pleuropneumoniae in large groups of animals in relatively small spaces. These conditions presumably favor the horizontal dissemination of apxIA gene mutations within bacterial populations with host reservoirs. As a result, the same serovar can demonstrate different antigenic capacities due to mutations in the apxIA gene. These alterations in sequences of the apxIA gene could occur in other areas of countries with intense swine production, which could lead to differences in the pathogenicity and immunogenicity of each serovar and have implications for the clinical status or diagnosis of A. pleuropneumoniae.
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Affiliation(s)
- Lucas Fernando dos Santos
- Laboratory of Bacterial Diseases, Sector of Preventive Veterinary Medicine and Public Health, Veterinary Department, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
- Microbiologia Veterinária Especial LTDA (Microvet), Viçosa, Minas Gerais, Brazil
| | - Richard Costa Polveiro
- Laboratory of Bacterial Diseases, Sector of Preventive Veterinary Medicine and Public Health, Veterinary Department, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - Thalita Scatamburlo Moreira
- Laboratory of Bacterial Diseases, Sector of Preventive Veterinary Medicine and Public Health, Veterinary Department, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - Pedro Marcus Pereira Vidigal
- Núcleo de Análise de Biomoléculas (NuBioMol), Center of Biological Sciences, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - Yung-Fu Chang
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
| | - Maria Aparecida Scatamburlo Moreira
- Laboratory of Bacterial Diseases, Sector of Preventive Veterinary Medicine and Public Health, Veterinary Department, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
- * E-mail:
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Abstract
A total of 255 Actinobacillus pleuropneumoniae isolates were collected from 634 lung samples representing 70 swine herds in Hungary between January 2012 and June 2016. On the basis of the indirect haemagglutination test 77 independent strains were included in the evaluation after the elimination of duplicate or multiple serotypes from the same herd. In the case of 7 herds strains of two different serotypes were identified. Fourteen Hungarian A. pleuropneumoniae isolates from the culture collection of the Department of Microbiology and Infectious Diseases, isolated before 2012, were also included in the evaluation (one each from 12 herds and two each from two herds, where two serotypes occurred). Out of the altogether 91 A. pleuropneumoniae strains 72 strains belonged to biotype I and 19 strains could be allocated to biotype II. In Hungary, the most common serotypes were serotype 2 (39.5%), 13 (15.4%), 8 (8.8%) and 16 (8.8%), but serotypes 9 (5.5%), 11 (3.3%) and 12 (3.3%) were also isolated. Twelve strains (13.2%) were untypable.
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Affiliation(s)
- Rita Sárközi
- Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, H-1581 Budapest, P.O.B. 22, Hungary
| | - László Makrai
- Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, H-1581 Budapest, P.O.B. 22, Hungary
| | - László Fodor
- Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, H-1581 Budapest, P.O.B. 22, Hungary
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Galactose-1-phosphate uridyltransferase (GalT), an in vivo-induced antigen of Actinobacillus pleuropneumoniae serovar 5b strain L20, provided immunoprotection against serovar 1 strain MS71. PLoS One 2018; 13:e0198207. [PMID: 29856812 PMCID: PMC5983418 DOI: 10.1371/journal.pone.0198207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 05/15/2018] [Indexed: 11/19/2022] Open
Abstract
GALT is an important antigen of Actinobacillus pleuropneumoniae (APP), which was shown to provide partial protection against APP infection in a previous study in our lab. The main purpose of the present study is to investigate GALT induced cross-protection between different APP serotypes and elucidate key mechanisms of the immune response to GALT antigenic stimulation. Bioinformatic analysis demonstrated that galT is a highly conserved gene in APP, widely distributed across multiple pathogenic strains. Homologies between any two strains ranges from 78.9% to 100% regarding the galT locus. Indirect enzyme-linked immunosorbent assay (ELISA) confirmed that GALT specific antibodies could not be induced by inactivated APP L20 or MS71 whole cell bacterin preparations. A recombinant fusion GALT protein derived from APP L20, however has proven to be an effective cross-protective antigen against APP sevorar 1 MS71 (50%, 4/8) and APP sevorar 5b L20 (75%, 6/8). Histopathological examinations have confirmed that recombinant GALT vaccinated animals showed less severe pathological signs in lung tissues than negative controls after APP challenge. Immunohistochemical (IHC) analysis indicated that the infiltration of neutrophils in the negative group is significantly increased compared with that in the normal control (P<0.001) and that in surviving animals is decreased compared to the negative group. Anti-GALT antibodies were shown to mediate phagocytosis of neutrophils. After interaction with anti-GALT antibodies, survival rate of APP challenged vaccinated animals was significantly reduced (P<0.001). This study demonstrated that GALT is an effective cross-protective antigen, which could be used as a potential vaccine candidate against multiple APP serotypes.
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Wu HC, Yeh PH, Hsueh KJ, Yang WJ, Chu CY. Recombinant ApxIV protein enhances protective efficacy against Actinobacillus pleuropneumoniae in mice and pigs. J Appl Microbiol 2018; 124:1366-1376. [PMID: 29431246 DOI: 10.1111/jam.13726] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 01/23/2018] [Accepted: 01/31/2018] [Indexed: 11/28/2022]
Abstract
AIMS Available bacterins, commercial or autogenous, for Actinobacillus pleuropneumoniae disease control have, thus far, shown debatable protective efficacy and only in homologous challenges. Our study sought to determine whether the addition of reombinant protein ApxIV to the multicomponent vaccine could enhance protection against homologous and heterologous challenge of A. pleuropneumoniae. METHODS AND RESULTS The virulence of ApxI, ApxII, ApxIV and OMP were cloned and expressed using a prokaryotic system; these recombinant proteins were combined with inactivated A. pleuropneumoniae serovar 1 to formulate different multicomponent vaccines. Immune response and protective efficacy of the vaccines were evaluated in mice and pigs. A protection rate of 67% was observed against heterologous challenge in mice vaccinated with the rApxIV formulation. Piglets vaccinated with vaccine containing ApxIV produced significantly higher antibody titre and provided complete protection and reduced gross lesions by 67% when compared with the nonimmunized group after homologous challenge. Additionally, flow cytometry analysis showed significant cellular immune response. CONCLUSIONS The results of our vaccination experiments revealed that a combination of inactivated bacteria and the recombinant antigens rApxI, rApxII, rApxIV and rOMP can provide effective protection against heterologous A. pleuropneumoniae challenge. SIGNIFICANCE AND IMPACT OF THE STUDY The addition of ApxIV to the multicomponent vaccine could enhance homologous and heterologous protection in mice and pigs, respectively, against challenge by A. pleuropneumoniae.
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Affiliation(s)
- H-C Wu
- Graduate Institute of Animal Vaccine Technology, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - P-H Yeh
- Graduate Institute of Animal Vaccine Technology, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - K-J Hsueh
- Graduate Institute of Animal Vaccine Technology, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan.,Department of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - W-J Yang
- Institute of Biotechnology, National University of Kaohsiung, Kaohsiung, Taiwan
| | - C-Y Chu
- Graduate Institute of Animal Vaccine Technology, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan
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Yee S, Blackall PJ, Turni C. Genetic diversity and toxin gene distribution among serovars ofActinobacillus pleuropneumoniaefrom Australian pigs. Aust Vet J 2018; 96:17-23. [DOI: 10.1111/avj.12660] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 07/25/2017] [Accepted: 07/31/2017] [Indexed: 11/29/2022]
Affiliation(s)
- S Yee
- EcoSciences Precinct, Queensland Alliance for Agriculture and Food Innovation; The University of Queensland; Boggo Road Dutton Park Queensland 4102 Australia
| | - PJ Blackall
- EcoSciences Precinct, Queensland Alliance for Agriculture and Food Innovation; The University of Queensland; Boggo Road Dutton Park Queensland 4102 Australia
| | - C Turni
- EcoSciences Precinct, Queensland Alliance for Agriculture and Food Innovation; The University of Queensland; Boggo Road Dutton Park Queensland 4102 Australia
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González W, Giménez-Lirola LG, Holmes A, Lizano S, Goodell C, Poonsuk K, Sitthicharoenchai P, Sun Y, Zimmerman J. Detection of Actinobacillus Pleuropneumoniae ApxIV Toxin Antibody in Serum and Oral Fluid Specimens from Pigs Inoculated Under Experimental Conditions. J Vet Res 2017; 61:163-171. [PMID: 29978069 PMCID: PMC5894388 DOI: 10.1515/jvetres-2017-0021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 05/26/2017] [Indexed: 11/15/2022] Open
Abstract
Introduction The prevention and control of Actinobacillus pleuropneumoniae in commercial production settings is based on serological monitoring. Enzyme-linked immunosorbent assays (ELISAs) have been developed to detect specific antibodies against a variety of A. pleuropneumoniae antigens, including long-chain lipopolysaccharides (LPS) and the ApxIV toxin, a repeats-in-toxin (RTX) exotoxin unique to A. pleuropneumoniae and produced by all serovars. The objective of this study was to describe ApxIV antibody responses in serum and oral fluid of pigs. Material and Methods Four groups of pigs (six pigs per group) were inoculated with A. pleuropneumoniae serovars 1, 5, 7, or 12. Weekly serum samples and daily oral fluid samples were collected from individual pigs for 56 days post inoculation (DPI) and tested by LPS and ApxIV ELISAs. The ApxIV ELISA was run in three formats to detect immunlgobulins M, G, and A (IgM, IgG and IgA) while the LPS ELISA detected only IgG. Results All pigs inoculated with A. pleuropneumoniae serovars 1 and 7 were LPS ELISA serum antibody positive from DPI 14 to 56. A transient and weak LPS ELISA antibody response was observed in pigs inoculated with serovar 5 and a single antibody positive pig was observed in serovar 12 at ≥35 DPI. Notably, ApxIV serum and oral fluid antibody responses in pig inoculated with serovars 1 and 7 reflected the patterns observed for LPS antibody, albeit with a 14 to 21 day delay. Conclusion This work suggests that ELISAs based on ApxIV antibody detection in oral fluid samples could be effective in population monitoring for A. pleuropneumoniae.
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Affiliation(s)
- Wendy González
- College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | | | - Ashley Holmes
- College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | | | | | - Korakrit Poonsuk
- College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | | | - Yaxuan Sun
- College of Liberal Arts and Sciences, Iowa State University, Ames, IA, USA
| | - Jeffrey Zimmerman
- College of Veterinary Medicine, Iowa State University, Ames, IA, USA
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Ito H, Takahashi S, Asai T, Tamura Y, Yamamoto K. Isolation and molecular characterization of a urease-negative Actinobacillus pleuropneumoniae mutant. J Vet Diagn Invest 2017; 30:172-174. [PMID: 29145759 DOI: 10.1177/1040638717742436] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
An atypical urease-negative mutant of Actinobacillus pleuropneumoniae serovar 2 was isolated in Japan. Nucleotide sequence analysis of the urease gene cluster revealed that the insertion of a short DNA sequence into the cbiM gene was responsible for the urease-negative activity of the mutant. Veterinary diagnostic laboratories should be watchful for the presence of aberrant urease-negative A. pleuropneumoniae isolates.
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Affiliation(s)
- Hiroya Ito
- The National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan (Ito).,Zen-Noh Institute of Animal Health, Sakura, Chiba, Japan (Takahashi).,Gifu University, Gifu, Gifu, Japan (Asai).,Rakuno Gakuen University, Ebetsu, Hokkaido, Japan (Tamura).,Tokyo University of Agriculture, Tokyo, Japan (Yamamoto)
| | - Sayaka Takahashi
- The National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan (Ito).,Zen-Noh Institute of Animal Health, Sakura, Chiba, Japan (Takahashi).,Gifu University, Gifu, Gifu, Japan (Asai).,Rakuno Gakuen University, Ebetsu, Hokkaido, Japan (Tamura).,Tokyo University of Agriculture, Tokyo, Japan (Yamamoto)
| | - Tetsuo Asai
- The National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan (Ito).,Zen-Noh Institute of Animal Health, Sakura, Chiba, Japan (Takahashi).,Gifu University, Gifu, Gifu, Japan (Asai).,Rakuno Gakuen University, Ebetsu, Hokkaido, Japan (Tamura).,Tokyo University of Agriculture, Tokyo, Japan (Yamamoto)
| | - Yutaka Tamura
- The National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan (Ito).,Zen-Noh Institute of Animal Health, Sakura, Chiba, Japan (Takahashi).,Gifu University, Gifu, Gifu, Japan (Asai).,Rakuno Gakuen University, Ebetsu, Hokkaido, Japan (Tamura).,Tokyo University of Agriculture, Tokyo, Japan (Yamamoto)
| | - Koshi Yamamoto
- The National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan (Ito).,Zen-Noh Institute of Animal Health, Sakura, Chiba, Japan (Takahashi).,Gifu University, Gifu, Gifu, Japan (Asai).,Rakuno Gakuen University, Ebetsu, Hokkaido, Japan (Tamura).,Tokyo University of Agriculture, Tokyo, Japan (Yamamoto)
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Sassu EL, Bossé JT, Tobias TJ, Gottschalk M, Langford PR, Hennig-Pauka I. Update on Actinobacillus pleuropneumoniae-knowledge, gaps and challenges. Transbound Emerg Dis 2017; 65 Suppl 1:72-90. [PMID: 29083117 DOI: 10.1111/tbed.12739] [Citation(s) in RCA: 104] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Indexed: 12/15/2022]
Abstract
Porcine pleuropneumonia, caused by the bacterial porcine respiratory tract pathogen Actinobacillus pleuropneumoniae, leads to high economic losses in affected swine herds in most countries of the world. Pigs affected by peracute and acute disease suffer from severe respiratory distress with high lethality. The agent was first described in 1957 and, since then, knowledge about the pathogen itself, and its interactions with the host, has increased continuously. This is, in part, due to the fact that experimental infections can be studied in the natural host. However, the fact that most commercial pigs are colonized by this pathogen has hampered the applicability of knowledge gained under experimental conditions. In addition, several factors are involved in development of disease, and these have often been studied individually. In a DISCONTOOLS initiative, members from science, industry and clinics exchanged their expertise and empirical observations and identified the major gaps in knowledge. This review sums up published results and expert opinions, within the fields of pathogenesis, epidemiology, transmission, immune response to infection, as well as the main means of prevention, detection and control. The gaps that still remain to be filled are highlighted, and present as well as future challenges in the control of this disease are addressed.
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Affiliation(s)
- E L Sassu
- Department of Pathobiology, Institute of Immunology, University of Veterinary Medicine, Vienna, Austria
| | - J T Bossé
- Section of Paediatrics, Department of Medicine, Imperial College London, London, UK
| | - T J Tobias
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - M Gottschalk
- Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada
| | - P R Langford
- Section of Paediatrics, Department of Medicine, Imperial College London, London, UK
| | - I Hennig-Pauka
- Field Station for Epidemiology, University of Veterinary Medicine Hannover, Foundation, Bakum, Germany
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To H, Teshima K, Nagai S, Zielinski GC, Koyama T, Lee J, Bessone FA, Nagano T, Oshima A, Tsutsumi N. Characterization of Actinobacillus pleuropneumoniae field strains antigenically related to the 3-6-8-15 group from diseased pigs in Japan and Argentina. Rev Argent Microbiol 2017; 50:12-22. [PMID: 28886933 DOI: 10.1016/j.ram.2017.04.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 03/08/2017] [Accepted: 04/20/2017] [Indexed: 11/30/2022] Open
Abstract
The objectives of this study were to determine the serovar of a collection of Actinobacillus pleuropneumoniae strains within the 3-6-8-15 cross-reacting group and to analyze their phenotypic and genetic properties. Based on the serological tests, forty-seven field strains of Actinobacillus pleuropneumoniae isolated from lungs with pleuropneumonia lesions in Japan and Argentina were found to be serovars belonging to the 3-6-8-15 cross-reacting group. By using a capsule loci-based PCR, twenty-nine (96.7%) and one (3.3%) from Japan were identified as serovars 15 and 8, respectively, whereas seventeen (100%) from Argentina were identified as serovar 8. The findings suggested that serovars 8 and 15 were prevalent within the 3-6-8-15 cross-reacting group, in Argentina and Japan, respectively. Phenotypic analyses revealed that the protein patterns observed on SDS-PAGE and the lipopolysaccharide antigen detected by immunoblotting of the reference and field strains of serovars 8 and 15 were similar to each other. Genetic (16S rDNA, apxIIA, apxIIIA, cps, cpx genes, apx and omlA patterns) analyses revealed that the apxIIA and apxIIIA genes of the field strains of serovars 8 and 15 were similar to those of the reference strains of serovars 3, 4, 6, 8 and 15. The results obtained in the present study may be useful for the development of more effective vaccines against disease caused by A. pleuropneumoniae by including the homologous antigens to the most prevalent serovars in specific geographical areas.
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Affiliation(s)
- Ho To
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan.
| | - Kaho Teshima
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
| | - Shinya Nagai
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
| | - Gustavo C Zielinski
- Animal Health Group, Estacion Experimental Agropecuaria Marcos Juarez, INTA, CC n°21 (2580), Marcos Juarez, Province of Cordoba, Argentina.
| | - Tomohiro Koyama
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
| | - Jina Lee
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
| | - Fernando A Bessone
- Animal Health Group, Estacion Experimental Agropecuaria Marcos Juarez, INTA, CC n°21 (2580), Marcos Juarez, Province of Cordoba, Argentina
| | - Tetsuji Nagano
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
| | - Atsushi Oshima
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
| | - Nobuyuki Tsutsumi
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
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Polyamine-binding protein PotD2 is required for stress tolerance and virulence in Actinobacillus pleuropneumoniae. Antonie van Leeuwenhoek 2017; 110:1647-1657. [DOI: 10.1007/s10482-017-0914-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 07/15/2017] [Indexed: 10/19/2022]
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Liu J, Ma Q, Yang F, Zhu R, Gu J, Sun C, Feng X, Du C, Langford PR, Han W, Yang J, Lei L. B cell cross-epitope of Propionibacterium acnes and Actinobacillus pleuropneumonia selected by phage display library can efficiently protect from Actinobacillus pleuropneumonia infection. Vet Microbiol 2017. [PMID: 28622855 DOI: 10.1016/j.vetmic.2017.04.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Contagious porcine pleuropneumonia (CPP), caused by Actinobacillus pleuropneumoniae (APP), is a highly transmissible and fatal respiratory illness that causes tremendous economic losses for the pig breeding industry worldwide. Propionibacterium acnes (PA) has a strong cross-reaction with anti-APP1 and anti-APP5 serum and can efficiently prevent APP infection, which was fortuitously found in researching the differential gene between the different APP serotypes. There seems to be some natural cross-protection between PA and APP. To identify the common epitope, the phage display library of a PA whole genome was constructed, whose size is 105. The DNA sequence of the positive clone was determined after three rounds of biopanning, and ten common protein types were identified and the epitope was predicted by computer software. Six peptide epitopes were selected and synthesized for further analysis. Among these epitopes, Ba1, Bb5 and C1 could bind to anti-PA serum and anti-APP1 serum and vice versa. Furthermore, the IgG and IL-4 levels and CD4+/CD8+ T cell ratios in the Ba1, Bb5 and C1 groups were significantly higher than that in the control group, indicating that the epitopes could trigger an immune response, which was mainly humoral immunity. Moreover, Ba1 and Bb5 equally protected 80% of mice from a fatal dose of APP1 infection compared with the control group. Mice could resist APP1 and APP5 challenge after being treated with the combination of Ba1 and Bb5, with survival rates of 80% and 90%, respectively. These findings suggest that the PA epitope confers antigenicity and can heterologously resist to the APP infection. This finding provides a novel strategy for preventing APP infection.
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Affiliation(s)
- Jianfang Liu
- College of Veterinary Medicine, Jinlin University, Changchun, Jilin, 130062, People's Republic of China
| | - Qiuyue Ma
- College of Veterinary Medicine, Jinlin University, Changchun, Jilin, 130062, People's Republic of China
| | - Feng Yang
- College of Veterinary Medicine, Jinlin University, Changchun, Jilin, 130062, People's Republic of China
| | - Rining Zhu
- College of Veterinary Medicine, Jinlin University, Changchun, Jilin, 130062, People's Republic of China
| | - Jingmin Gu
- College of Veterinary Medicine, Jinlin University, Changchun, Jilin, 130062, People's Republic of China
| | - Changjiang Sun
- College of Veterinary Medicine, Jinlin University, Changchun, Jilin, 130062, People's Republic of China
| | - Xin Feng
- College of Veterinary Medicine, Jinlin University, Changchun, Jilin, 130062, People's Republic of China
| | - Chongtao Du
- College of Veterinary Medicine, Jinlin University, Changchun, Jilin, 130062, People's Republic of China
| | - Paul R Langford
- Section of Paediatrics, Imperial College London, St. Mary's Campus, London W2 1 PG, United Kingdom
| | - Wenyu Han
- College of Veterinary Medicine, Jinlin University, Changchun, Jilin, 130062, People's Republic of China
| | - Junling Yang
- Department of Respiratory Medicine, The Second Hospital of Jilin University, Changchun, Jilin, 130062, People's Republic of China
| | - Liancheng Lei
- College of Veterinary Medicine, Jinlin University, Changchun, Jilin, 130062, People's Republic of China.
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To H, Nagai S, Iwata A, Koyama T, Oshima A, Tsutsumi N. Genetic and antigenic characteristics of ApxIIA and ApxIIIA from Actinobacillus pleuropneumoniae serovars 2, 3, 4, 6, 8 and 15. Microbiol Immunol 2017; 60:447-58. [PMID: 27211905 DOI: 10.1111/1348-0421.12388] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 04/21/2016] [Accepted: 05/16/2016] [Indexed: 11/30/2022]
Abstract
Apx toxins produced by Actinobacillus pleuropneumoniae are essential components of new generation vaccines. In this study, apxIIA and apxIIIA genes of serovars 2, 3, 4, 6, 8 and 15 were cloned and sequenced. Amino acid sequences of ApxIIA proteins of serovars 2, 3, 4, 6, 8 and 15 were almost identical to those of serovars 1, 5, 7, 9 and 11-13. Immunoblot analysis showed that rApxIIA from serovars 2 and 15 reacts strongly with sera from animals infected with various serovars. Sequence analysis revealed that ApxIIIA proteins has two variants, one in strains of serovar 2 and the other in strains of serovars 3, 4, 6, 8 and 15. A mouse cross-protection study showed that mice actively immunized with rApxIIIA/2 or rApxIIIA/15 are protected against challenge with A. pleuropneumoniae strains of serovars 3, 4, 6, 8, 15, and 2 expressing ApxIII/15 and ApxIII/2, respectively. Similarly, mice passively immunized with rabbit anti-rApxIIIA/2 or anti-rApxIIIA/15 sera were found to be protected against challenge with strains of serovars 2 and 15. Our study revealed antigenic and sequence similarities within ApxIIA and ApxIIIA proteins, which may help in the development of effective vaccines against disease caused by A. pleuropneumoniae.
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Affiliation(s)
- Ho To
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
| | - Shinya Nagai
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
| | - Akira Iwata
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
| | - Tomohiro Koyama
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
| | - Atsushi Oshima
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
| | - Nobuyuki Tsutsumi
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
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Xie F, Li G, Zhou L, Zhang Y, Cui N, Liu S, Wang C. Attenuated Actinobacillus pleuropneumoniae double-deletion mutant S-8∆clpP/apxIIC confers protection against homologous or heterologous strain challenge. BMC Vet Res 2017; 13:14. [PMID: 28061786 PMCID: PMC5219649 DOI: 10.1186/s12917-016-0928-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 12/15/2016] [Indexed: 11/18/2022] Open
Abstract
Background Actinobacillus pleuropneumoniae is the etiological agent of porcine pleuropneumonia, which leads to large economic losses to the swine industry worldwide. In this study, S-8△clpP△apxIIC, a double-deletion mutant of A. pleuropneumoniae was constructed, and its safety and protective efficacy were evaluated in pigs. Results The S-8△clpP△apxIIC mutant exhibited attenuated virulence in a murine (BALB/c) model, and caused no detrimental effects on pigs even at a dose of up to 1.0 × 109 CFU. Furthermore, the S-8△clpP△apxIIC mutant was able to induce a strong immune response in pigs, which included high levels of IgG1 and IgG2, stimulated gamma interferon (IFN-γ), interleukin 12 (IL-12), and interleukin 4 (IL-4) production, and conferred effective protection against the lethal challenge with A. pleuropneumoniae serovars 7 or 5a. The pigs in the S-8△clpP△apxIIC immunized groups have no lesions and reduced bacterial loads in the lung tissue after challenge. Conclusions The data obtained in this study suggest that the S-8△clpP△apxIIC mutant can serve as a highly immunogenic and potential live attenuated vaccine candidate against A. pleuropneumoniae infection.
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Affiliation(s)
- Fang Xie
- State Key Laboratory of Veterinary Biotechnology, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, Heilongjiang, People's Republic of China
| | - Gang Li
- State Key Laboratory of Veterinary Biotechnology, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, Heilongjiang, People's Republic of China
| | - Long Zhou
- State Key Laboratory of Veterinary Biotechnology, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, Heilongjiang, People's Republic of China
| | - Yanhe Zhang
- State Key Laboratory of Veterinary Biotechnology, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, Heilongjiang, People's Republic of China
| | - Ning Cui
- State Key Laboratory of Veterinary Biotechnology, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, Heilongjiang, People's Republic of China
| | - Siguo Liu
- State Key Laboratory of Veterinary Biotechnology, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, Heilongjiang, People's Republic of China
| | - Chunlai Wang
- State Key Laboratory of Veterinary Biotechnology, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, Heilongjiang, People's Republic of China.
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A Unique Capsule Locus in the Newly Designated Actinobacillus pleuropneumoniae Serovar 16 and Development of a Diagnostic PCR Assay. J Clin Microbiol 2017; 55:902-907. [PMID: 28053219 PMCID: PMC5328458 DOI: 10.1128/jcm.02166-16] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 12/22/2016] [Indexed: 11/29/2022] Open
Abstract
Actinobacillus pleuropneumoniae causes pleuropneumonia, an economically significant lung disease of pigs. Recently, isolates of A. pleuropneumoniae that were serologically distinct from the previously characterized 15 serovars were described, and a proposal was put forward that they comprised a new serovar, serovar 16. Here we used whole-genome sequencing of the proposed serovar 16 reference strain A-85/14 to confirm the presence of a unique capsular polysaccharide biosynthetic locus. For molecular diagnostics, primers were designed from the capsule locus of strain A-85/14, and a PCR was formulated that differentiated serovar 16 isolates from all 15 known serovars and other common respiratory pathogenic/commensal bacteria of pigs. Analysis of the capsule locus of strain A-85/14 combined with the previous serological data show the existence of a sixteenth serovar—designated serovar 16—of A. pleuropneumoniae.
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Ito H, Ogawa T, Fukamizu D, Morinaga Y, Kusumoto M. Nucleotide sequence analysis of a DNA region involved in capsular polysaccharide biosynthesis reveals the molecular basis of the nontypeability of two Actinobacillus pleuropneumoniae isolates. J Vet Diagn Invest 2016; 28:632-637. [PMID: 27694188 DOI: 10.1177/1040638716656026] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The aim of our study was to reveal the molecular basis of the serologic nontypeability of 2 Actinobacillus pleuropneumoniae field isolates. Nine field strains of A. pleuropneumoniae, the causative agent of porcine pleuropneumonia, were isolated from pigs raised on the same farm and sent to our diagnostic laboratory for serotyping. Seven of the 9 strains were identified as serovar 15 strains by immunodiffusion tests. However, 2 strains, designated FH24-2 and FH24-5, could not be serotyped with antiserum prepared against serovars 1-15. Strain FH24-5 showed positive results in 2 serovar 15-specific PCR tests, whereas strain FH24-2 was only positive in 1 of the 2 PCR tests. The nucleotide sequence analysis of gene clusters involved in capsular polysaccharide biosynthesis of the 2 nontypeable strains revealed that both had been rendered nontypeable by the action of ISApl1, a transposable element of A. pleuropneumoniae belonging to the IS30 family. The results showed that ISApl1 of A. pleuropneumoniae can interfere with both the serologic and molecular typing methods, and that nucleotide sequence analysis across the capsular gene clusters is the best means of determining the cause of serologic nontypeability in A. pleuropneumoniae.
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Affiliation(s)
- Hiroya Ito
- The National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan (Ito, Kusumoto)Fukuoka Chuo Livestock Hygiene Center, Higashi-ku, Fukuoka, Japan (Ogawa, Fukamizu, Morinaga)
| | - Torata Ogawa
- The National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan (Ito, Kusumoto)Fukuoka Chuo Livestock Hygiene Center, Higashi-ku, Fukuoka, Japan (Ogawa, Fukamizu, Morinaga)
| | - Dai Fukamizu
- The National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan (Ito, Kusumoto)Fukuoka Chuo Livestock Hygiene Center, Higashi-ku, Fukuoka, Japan (Ogawa, Fukamizu, Morinaga)
| | - Yuiko Morinaga
- The National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan (Ito, Kusumoto)Fukuoka Chuo Livestock Hygiene Center, Higashi-ku, Fukuoka, Japan (Ogawa, Fukamizu, Morinaga)
| | - Masahiro Kusumoto
- The National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan (Ito, Kusumoto)Fukuoka Chuo Livestock Hygiene Center, Higashi-ku, Fukuoka, Japan (Ogawa, Fukamizu, Morinaga)
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Morioka A, Shimazaki Y, Uchiyama M, Suzuki S. Serotyping reanalysis of unserotypable Actinobacillus pleuropneumoniae isolates by agar gel diffusion test. J Vet Med Sci 2016; 78:723-5. [PMID: 26726101 PMCID: PMC4873870 DOI: 10.1292/jvms.15-0538] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We observed increasing unserotypable (UT) Actinobacillus
pleuropneumoniae isolates using agar gel diffusion (AGD) test. To reanalyze
their serovar, we performed rapid slide agglutination (RSA) test and multiplex PCR for 47
UT isolates. Of these, 25 were serovar 1 (UT-serovar 1), 20 were serovar 2 (UT-serovar 2)
and 2 were serovar 15 (UT-serovar 15). We examined serotyping antigen extraction
temperature to determine heat influence. UT-serovar 1 and 15 were influenced by heat,
because their precipitation lines were observed in the case of low antigen extraction
temperature. To investigate the relationship between antigenicity and genotype, we
performed pulsed-field gel electrophoresis (PFGE) analysis using UT-serovar 2 and 15. The
predominant PFGE pattern of UT-serovar 2 was identical to that of serovar 2.
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Affiliation(s)
- Ayako Morioka
- National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, 1-15-1 Tokura, Kokubunji, Tokyo 185-8511, Japan
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Hur J, Eo SK, Park SY, Choi Y, Lee JH. Immunological study of an attenuated Salmonella Typhimurium expressing ApxIA, ApxIIA, ApxIIIA and OmpA of Actinobacillus pleuropneumoniae in a mouse model. J Vet Med Sci 2015; 77:1693-6. [PMID: 26227587 PMCID: PMC4710733 DOI: 10.1292/jvms.14-0428] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Salmonella Typhimurium strain expressing the Actinobacillus
pleuropneumoniae antigens, ApxIA, ApxIIA, ApxIIIA and OmpA, was previously
constructed as a vaccine candidate for porcine pleuropneumonia. This strain was a live
attenuated (∆lon∆cpxR∆asd)Salmonella as a delivery host
and contained a vector containing asd. An immunological study of
lymphocyte proliferation, T-lymphocyte subsets and cytokines in the splenocytes of a mouse
model was carried out after stimulation with the candidate Salmonella
Typhimurium by intranasal inoculation. The splenic lymphocyte proliferation and the levels
of IL-4, IL-6 and IL-12 of the inoculated mice were significantly increased, and the T-
and B-cell populations were also elevated. Collectively, the candidate may efficiently
induce the Th1- and Th2-type immune responses.
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Affiliation(s)
- Jin Hur
- Department of Bioactive Material Sciences, and Department of Veterinary Public Health, College of Veterinary Medicine, Chonbuk National University, Jeonju 561-756, South Korea
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Abstract
The introduction into a naïve herd of animals sub-clinically infected with Actinobacillus pleuropneumoniae (App) is frequently the cause of clinical pleuropneumonia and the identification of such infected herds is a priority in the control of disease. Different serological tests for App have been developed and a number of these are routinely used. Some are species-specific whereas others identify more specifically the serotype/serogroup involved which requires updated information about important serotypes recovered from diseased pigs in a given area/country. Serotyping methods based on molecular techniques have been developed lately and are ready to be used by most diagnostic laboratories. When non-conclusive serological results are obtained, direct detection of App from tonsils is sometimes attempted. This review addresses different techniques and approaches used to monitor herds sub-clinically infected by this important pathogen.
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Affiliation(s)
- Marcelo Gottschalk
- Department of Pathology and Microbiology, Swine and Poultry Infectious Disease Center (CRIPA), Groupe de Recherche sur les Maladies Infectieuses du Porc (GREMIP), Faculty of Veterinary Medicine, University of Montreal, St-Hyacinthe, Québec, Canada J2S 2M2.
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Draft Genome Sequences of Six Actinobacillus pleuropneumoniae Serotype 8 Brazilian Clinical Isolates: Insight into New Applications. GENOME ANNOUNCEMENTS 2015; 3:3/2/e01585-14. [PMID: 25745011 PMCID: PMC4358398 DOI: 10.1128/genomea.01585-14] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Actinobacillus pleuropneumoniae is the causative agent of swine pleuropneumonia, a highly contagious disease associated with pigs of all ages that results in severe economic losses to the industry. Here, we report for the first time six genome sequences of A. pleuropneumoniae clinical isolates of serotype 8, found worldwide.
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Ma Q, Sun C, Yang F, Wang L, Qin W, Xia X, Feng X, Du C, Gu J, Han W, Lei L. Macrophages largely contribute to heterologous anti-Propionibacterium acnes antibody-mediated protection from Actinobacillus pleuropneumoniae infection in mice. Microbiol Immunol 2015; 59:166-73. [PMID: 25644652 DOI: 10.1111/1348-0421.12240] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Revised: 01/05/2015] [Accepted: 01/26/2015] [Indexed: 11/29/2022]
Abstract
Actinobacillus pleuropneumoniae is the causative agent of acute and chronic pleuropneumonia. Propionibacterium acnes is a facultative anaerobic gram-positive corynebacterium. We have previously found that anti-P. acnes antibodies can prevent A. pleuropneumoniae infections in mice. To investigate the role of macrophages in this process, affinity-purified anti-P. acnes IgG and anti-A. pleuropneumoniae IgG were used in opsonophagocytosis assays. Additionally, the efficacy of passive immunization with P. acnes serum against A. pleuropneumoniae was tested in macrophage-depleted mice. It was found that anti-P. acnes IgG had an effect similar to that of anti-A. pleuropneumoniae IgG (P > 0.05), which significantly promotes phagocytosis of A. pleuropneumoniae by macrophages (P < 0.01). It was also demonstrated that, after passive immunization with anti-P. acnes serum, macrophage-replete mice had the highest survival rate (90%), whereas the survival rate of macrophage-depleted mice was only 40% (P < 0.05). However, macrophage-depleted mice that had been passively immunized with naïve serum had the lowest survival rate (20%), this rate being lower than that of macrophage-replete mice that had been passively immunized with naïve serum. Overall, anti-P. acnes antibodies did not prevent A. pleuropneumoniae infection under conditions of macrophage depletion (P > 0.05). Furthermore, in mice that had been passively immunized with anti-P. acnes serum, macrophage depletion resulted in a greater A. pleuropneumoniae burden and more severe pathological features of pneumonia in lung tissues than occurred in macrophage-replete mice. It was concluded that macrophages are essential for the process by which anti-P. acnes antibody prevents A. pleuropneumoniae infection in mice.
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Affiliation(s)
- Qiuyue Ma
- College of Veterinary Medicine, Jilin University, Changchun, China
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Ito H. The genetic organization of the capsular polysaccharide biosynthesis region of Actinobacillus pleuropneumoniae serotype 14. J Vet Med Sci 2015; 77:583-6. [PMID: 25648373 PMCID: PMC4478738 DOI: 10.1292/jvms.14-0174] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The genetic organization of the gene involved in the capsular polysaccharide
(CPS) biosynthesis of Actinobacillus pleuropneumoniae serotype 14 has
been determined. The DNA region for the CPS biosynthesis of serotype 14
(cps14) comprised 9 open reading frames, designated as
cps14AB1B2B3CDEFG genes, encoding
Cps14A to Cps14G protein, respectively. Cps14A was similar to CpsA of A.
pleuropneumoniae serotypes 1, 4 and 12; the Cps14B1 and
Cps14B2 were similar to CpsB of A. pleuropneumoniae
serotypes 1, 4 and 12, suggesting that CPS structure of A.
pleuropneumoniae serotype 14 would belong to Group I including A.
pleuropneumoniae serotypes 1, 4, 12 and 15. Surprisingly, the overall
nucleotide sequence, deduced amino acid sequence, and the genetic organization of the
cps14 were nearly identical to those of Actinobacillus
suis. This study will provide the molecular basic knowledge for development of
diagnostics and vaccine of A. pleuropneumoniae serotype 14.
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Affiliation(s)
- Hiroya Ito
- National Institute of Animal Health, National Agriculture and Food Research Organization, 3-1-5 Kannondai, Tsukuba, Ibaraki, Japan
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Ito H, Sueyoshi M. The genetic organization of the capsular polysaccharide biosynthesis region of Actinobacillus pleuropneumoniae serotype 15. J Vet Med Sci 2014; 77:483-6. [PMID: 25502540 PMCID: PMC4427752 DOI: 10.1292/jvms.14-0203] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Nucleotide sequence determination and analysis of the cps gene involved
in the capsular polysaccharide biosynthesis of Actinobacillus
pleuropneumoniae serotype 15 revealed the presence of three open reading
frames, designated as cps15ABC genes. At the protein level, Cps15A and
Cps15B showed considerably high homology to CpsA (67.0 to 68.7%) and CpsB (31.7 to 36.8%),
respectively, of A. pleuropneumoniae serotypes 1, 4 and 12, revealing the
common genetic organization of the cps among serotypes 1, 4, 12 and 15.
However, Cps15C showed no homology to any proteins of A. pleuropneumoniae
serotypes, indicating that cps15C may be specific to serotype 15. This
study will provide the basic molecular knowledge necessary for the development of
diagnostics and a vaccine for A. pleuropneumoniae serotype 15.
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Affiliation(s)
- Hiroya Ito
- National Institute of Animal Health, National Agriculture and Food Research Organization, 3-1-5 Kannondai, Tsukuba, Ibaraki 305-0856, Japan
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Pereira MF, Rossi CC, Vieira de Queiroz M, Martins GF, Isaac C, Bossé JT, Li Y, Wren BW, Terra VS, Cuccui J, Langford PR, Bazzolli DMS. Galleria mellonella is an effective model to study Actinobacillus pleuropneumoniae infection. MICROBIOLOGY-SGM 2014; 161:387-400. [PMID: 25414045 DOI: 10.1099/mic.0.083923-0] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Actinobacillus pleuropneumoniae is responsible for swine pleuropneumonia, a respiratory disease that causes significant global economic loss. Its virulence depends on many factors, such as capsular polysaccharides, RTX toxins and iron-acquisition systems. Analysis of virulence may require easy-to-use models that approximate mammalian infection and avoid ethical issues. Here, we investigate the potential use of the wax moth Galleria mellonella as an informative model for A. pleuropneumoniae infection. Genotypically distinct A. pleuropneumoniae clinical isolates were able to kill larvae at 37 °C but had different LD50 values, ranging from 10(4) to 10(7) c.f.u. per larva. The most virulent isolate (1022) was able to persist and replicate within the insect, while the least virulent (780) was rapidly cleared. We observed a decrease in haemocyte concentration, aggregation and DNA damage post-infection with isolate 1022. Melanization points around bacterial cells were observed in the fat body and pericardial tissues of infected G. mellonella, indicating vigorous cell and humoral immune responses close to the larval dorsal vessel. As found in pigs, an A. pleuropneumoniae hfq mutant was significantly attenuated for infection in the G. mellonella model. Additionally, the model could be used to assess the effectiveness of several antimicrobial agents against A. pleuropneumoniae in vivo. G. mellonella is a suitable inexpensive alternative infection model that can be used to study the virulence of A. pleuropneumoniae, as well as assess the effectiveness of antimicrobial agents against this pathogen.
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Affiliation(s)
- Monalessa Fábia Pereira
- Laboratório de Genética Molecular de Micro-organismos, Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária - BIOAGRO, Universidade Federal de Viçosa, Viçosa, Brazil
| | - Ciro César Rossi
- Laboratório de Genética Molecular de Micro-organismos, Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária - BIOAGRO, Universidade Federal de Viçosa, Viçosa, Brazil
| | - Marisa Vieira de Queiroz
- Laboratório de Genética Molecular de Micro-organismos, Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária - BIOAGRO, Universidade Federal de Viçosa, Viçosa, Brazil
| | - Gustavo Ferreira Martins
- Laboratório de Biologia Molecular de Insetos, Departamento de Biologia Geral, Universidade Federal de Viçosa, Viçosa, Brazil
| | - Clement Isaac
- Department of Zoology, Ambrose Alli University, Akpoma, Nigeria.,Laboratório de Biologia Molecular de Insetos, Departamento de Biologia Geral, Universidade Federal de Viçosa, Viçosa, Brazil
| | - Janine T Bossé
- Section of Paediatrics, Imperial College London, London, UK
| | - Yanwen Li
- Section of Paediatrics, Imperial College London, London, UK
| | - Brendan W Wren
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Vanessa Sofia Terra
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Jon Cuccui
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | | | - Denise Mara Soares Bazzolli
- Laboratório de Genética Molecular de Micro-organismos, Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária - BIOAGRO, Universidade Federal de Viçosa, Viçosa, Brazil
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The generation of successive unmarked mutations and chromosomal insertion of heterologous genes in Actinobacillus pleuropneumoniae using natural transformation. PLoS One 2014; 9:e111252. [PMID: 25409017 PMCID: PMC4237320 DOI: 10.1371/journal.pone.0111252] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 09/26/2014] [Indexed: 12/24/2022] Open
Abstract
We have developed a simple method of generating scarless, unmarked mutations in Actinobacillus pleuropneumoniae by exploiting the ability of this bacterium to undergo natural transformation, and with no need to introduce plasmids encoding recombinases or resolvases. This method involves two successive rounds of natural transformation using linear DNA: the first introduces a cassette carrying cat (which allows selection by chloramphenicol) and sacB (which allows counter-selection using sucrose) flanked by sequences to either side of the target gene; the second transformation utilises the flanking sequences ligated directly to each other in order to remove the cat-sacB cassette. In order to ensure efficient uptake of the target DNA during transformation, A. pleuropneumoniae uptake sequences are added into the constructs used in both rounds of transformation. This method can be used to generate multiple successive deletions and can also be used to introduce targeted point mutations or insertions of heterologous genes into the A. pleuropneumoniae chromosome for development of live attenuated vaccine strains. So far, we have applied this method to highly transformable isolates of serovars 8 (MIDG2331), which is the most prevalent in the UK, and 15 (HS143). By screening clinical isolates of other serovars, it should be possible to identify other amenable strains.
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Ito H, Matsumoto A. Isolation and genetic characterization of an Actinobacillus pleuropneumoniae serovar K12:O3 strain. J Vet Diagn Invest 2014; 27:102-6. [PMID: 25387844 DOI: 10.1177/1040638714555898] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
An atypical Actinobacillus pleuropneumoniae serovar 12 strain, termed QAS106, was isolated from a clinical case of porcine pleuropneumonia in Japan. An immunodiffusion (ID) test identified the strain as serovar 12. However, the ID test also demonstrated that strain QAS106 shared antigenic determinants with both the serovar 3 and 15 reference strains. Strain QAS106 was positive in the capsular serovar 12-specific polymerase chain reaction (PCR) assay, while the PCR toxin gene profiling and omlA PCR typing assays indicated that strain QAS106 was similar to serovar 3. The nucleotide sequence of the 16S ribosomal DNA (rDNA) of strain QAS106 was identical with that of serovars 3 and 12, but it showed 99.7% identity with that of serovar 15. Nucleotide sequence analysis revealed that genes involved in biosynthesis of the capsular polysaccharide (CPS) of strain QAS106 were identical to those of serovar 12 at the amino acid level. On the other hand, strain QAS106 would express putative proteins involved in the biosynthesis of lipopolysaccharide (LPS) O-polysaccharide (O-PS), the amino acid sequences of which were identical or nearly identical to those of serovars 3 and 15. In conclusion, strain QAS106 should be recognized as K12:O3, even though typical serovar 12 strains are K12:O12. The emergence of an atypical A. pleuropneumoniae serovar 12 strain expressing a rare combination of CPS and O-PS antigens would hamper precise serodiagnosis by the use of either CPS- or LPS-based serodiagnostic methodology alone.
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Affiliation(s)
- Hiroya Ito
- National Institute of Animal Health, National Agriculture and Food Research Organization, Ibaraki, Japan (Ito)Chiba Chuo Livestock Hygiene Service Center, Chiba, Japan (Matsumoto)
| | - Atsuko Matsumoto
- National Institute of Animal Health, National Agriculture and Food Research Organization, Ibaraki, Japan (Ito)Chiba Chuo Livestock Hygiene Service Center, Chiba, Japan (Matsumoto)
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Oral immunization against porcine pleuropneumonia using the cubic phase of monoolein and purified toxins of Actinobacillus pleuropneumoniae. Vaccine 2014; 32:6805-11. [PMID: 25446832 DOI: 10.1016/j.vaccine.2014.09.056] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 09/11/2014] [Accepted: 09/24/2014] [Indexed: 11/21/2022]
Abstract
The main goal of this work was to obtain an orally administered immunogen that would protect against infections by Actinobacillus pleuropneumoniae. The Apx I, II and III toxins were obtained from the supernatants of cultures of serotypes 1 and 3 of A. pleuropneumoniae. The capacity of monoolein gel to trap and protect the Apx toxins, and the effect of their incorporation on the stability of the cubic phase were evaluated. The gel was capable of trapping a 400-μg/ml concentration of the antigen with no effects on its structure. Approximately 60% of the protein molecules were released from the gel within 4h. Four experimental groups were formed, each one with four pigs. All challenges were conducted in a nebulization chamber. Group A: Control (-) not vaccinated and not challenged; Group B: Control (+) not vaccinated but challenged; Group C: vaccinated twice intramuscularly with ToxCom (a commercial toxoid) at an interval of 15 days and then challenged; and Group D: vaccinated orally twice a week for 4 weeks with ToxOral (an oral toxoid) and challenged on day 28 of the experiment with a same dose of 2.0 × 10(4) UFC of A. pleuropneumoniae serotypes 1 and 3. The lesions found in group B covered 27.7-43.1% of the lungs; the pigs in group C had lesions over 12.3-28%; and those in group D over 15.4-32.3%. No lesions were found in the Group A pigs. A. pleuropneumoniae induced macroscopic lesions characteristic of infection by and lesions microscopic detected by histopathology. The etiologic agent was recovered from the infected lungs, tonsils and spleen. The serotypes identified were 1 and 3. An indirect ELISA test identified the antibodies against the Apx toxins in the serum of the animals immunized orally.
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46
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Turni C, Singh R, Schembri MA, Blackall PJ. Evaluation of a multiplex PCR to identify and serotype Actinobacillus pleuropneumoniae serovars 1, 5, 7, 12 and 15. Lett Appl Microbiol 2014; 59:362-9. [PMID: 24863421 DOI: 10.1111/lam.12287] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 05/20/2014] [Accepted: 05/20/2014] [Indexed: 11/30/2022]
Abstract
The aim of this study was to validate a multiplex PCR for the species identification and serotyping of Actinobacillus pleuropneumoniae serovars 1, 5, 7, 12 and 15. All 15 reference strains and 411 field isolates (394 from Australia, 11 from Indonesia, five from Mexico and one from New Zealand) of A. pleuropneumoniae were tested with the multiplex PCR. The specificity of this multiplex PCR was validated on 26 non-A. pleuropneumoniae species. The multiplex PCR gave the expected results with all 15 serovar reference strains and agreed with conventional serotyping for all field isolates from serovars 1 (n = 46), 5 (n = 81), 7 (n = 80), 12 (n = 16) and serovar 15 (n = 117). In addition, a species-specific product was amplified in the multiplex PCR with all 411 A. pleuropneumoniae field isolates. Of 25 nontypeable field isolates only two did not yield a serovar-specific band in the multiplex PCR. This multiplex PCR for serovars 1, 5, 7, 12 and 15 is species specific and capable of serotyping isolates from diverse locations. Significance and impact of the study: A multiplex PCR that can recognize serovars 1, 5, 7, 12 and 15 of A. pleuropneumoniae was developed and validated. This novel diagnostic tool will enable frontline laboratories to provide key information (the serovar) to guide targeted prevention and control programmes for porcine pleuropneumonia, a serious economic disease of pigs. The previous technology, traditional serotyping, is typically provided by specialized reference laboratories, limiting the capacity to respond to this key disease.
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Affiliation(s)
- C Turni
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Dutton Park, Qld, Australia
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Luna-Castro S, Aguilar-Romero F, Samaniego-Barrón L, Godínez-Vargas D, de la Garza M. Effect of bovine apo-lactoferrin on the growth and virulence of Actinobacillus pleuropneumoniae. Biometals 2014; 27:891-903. [DOI: 10.1007/s10534-014-9752-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2014] [Accepted: 05/15/2014] [Indexed: 01/01/2023]
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Actinobacillus pleuropneumoniae possesses an antiviral activity against porcine reproductive and respiratory syndrome virus. PLoS One 2014; 9:e98434. [PMID: 24878741 PMCID: PMC4039538 DOI: 10.1371/journal.pone.0098434] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Accepted: 05/02/2014] [Indexed: 02/03/2023] Open
Abstract
Pigs are often colonized by more than one bacterial and/or viral species during respiratory tract infections. This phenomenon is known as the porcine respiratory disease complex (PRDC). Actinobacillus pleuropneumoniae (App) and porcine reproductive and respiratory syndrome virus (PRRSV) are pathogens that are frequently involved in PRDC. The main objective of this project was to study the in vitro interactions between these two pathogens and the host cells in the context of mixed infections. To fulfill this objective, PRRSV permissive cell lines such as MARC-145, SJPL, and porcine alveolar macrophages (PAM) were used. A pre-infection with PRRSV was performed at 0.5 multiplicity of infection (MOI) followed by an infection with App at 10 MOI. Bacterial adherence and cell death were compared. Results showed that PRRSV pre-infection did not affect bacterial adherence to the cells. PRRSV and App co-infection produced an additive cytotoxicity effect. Interestingly, a pre-infection of SJPL and PAM cells with App blocked completely PRRSV infection. Incubation of SJPL and PAM cells with an App cell-free culture supernatant is also sufficient to significantly block PRRSV infection. This antiviral activity is not due to LPS but rather by small molecular weight, heat-resistant App metabolites (<1 kDa). The antiviral activity was also observed in SJPL cells infected with swine influenza virus but to a much lower extent compared to PRRSV. More importantly, the PRRSV antiviral activity of App was also seen with PAM, the cells targeted by the virus in vivo during infection in pigs. The antiviral activity might be due, at least in part, to the production of interferon γ. The use of in vitro experimental models to study viral and bacterial co-infections will lead to a better understanding of the interactions between pathogens and their host cells, and could allow the development of novel prophylactic and therapeutic tools.
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Multiplex PCR assay for unequivocal differentiation of Actinobacillus pleuropneumoniae serovars 1 to 3, 5 to 8, 10, and 12. J Clin Microbiol 2014; 52:2380-5. [PMID: 24759717 PMCID: PMC4097740 DOI: 10.1128/jcm.00685-14] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
An improved multiplex PCR, using redesigned primers targeting the serovar 3 capsule locus, which differentiates serovars 3, 6, and 8 Actinobacillus pleuropneumoniae isolates, is described. The new primers eliminate an aberrant serovar 3-indicative amplicon found in some serovar 6 clinical isolates. Furthermore, we have developed a new multiplex PCR for the detection of serovars 1 to 3, 5 to 8, 10, and 12 along with apxIV, thus extending the utility of this diagnostic PCR to cover a broader range of isolates.
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Yoo AN, Cha SB, Shin MK, Won HK, Kim EH, Choi HW, Yoo HS. Serotypes and antimicrobial resistance patterns of the recent Korean Actinobacillus pleuropneumoniae
isolates. Vet Rec 2014; 174:223. [DOI: 10.1136/vr.101863] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- A. N. Yoo
- Department of Infectious Diseases; College of Veterinary Medicine and Brain Korea 21 Program for Veterinary Science; Seoul National University; Seoul 151-742 Korea
| | - S. B. Cha
- Department of Infectious Diseases; College of Veterinary Medicine and Brain Korea 21 Program for Veterinary Science; Seoul National University; Seoul 151-742 Korea
| | - M. K. Shin
- Department of Infectious Diseases; College of Veterinary Medicine and Brain Korea 21 Program for Veterinary Science; Seoul National University; Seoul 151-742 Korea
| | - H. K. Won
- Department of Infectious Diseases; College of Veterinary Medicine and Brain Korea 21 Program for Veterinary Science; Seoul National University; Seoul 151-742 Korea
- ChoongAng Vaccine Laboratory Co. Ltd.; Daejeon 305-348 Korea
| | - E. H. Kim
- ChoongAng Vaccine Laboratory Co. Ltd.; Daejeon 305-348 Korea
| | - H. W. Choi
- ChoongAng Vaccine Laboratory Co. Ltd.; Daejeon 305-348 Korea
| | - H. S. Yoo
- Department of Infectious Diseases; College of Veterinary Medicine and Brain Korea 21 Program for Veterinary Science; Seoul National University; Seoul 151-742 Korea
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