1
|
Seakamela EM, Henton MM, Jonker A, Kayoka-Kabongo PN, Matle I. Temporal and Serotypic Dynamics of Actinobacillus pleuropneumoniae in South African Porcine Populations: A Retrospective Study from 1985 to 2023. Pathogens 2024; 13:599. [PMID: 39057825 PMCID: PMC11280335 DOI: 10.3390/pathogens13070599] [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: 06/03/2024] [Revised: 07/03/2024] [Accepted: 07/17/2024] [Indexed: 07/28/2024] Open
Abstract
Actinobacillus pleuropneumoniae is a major bacterial pathogen causing porcine pleuropneumoniae, which is a disease of notable economic impact and high fatality rates among pigs worldwide. It has been reported that 19 distinct serotypes of this bacterium exist. Despite its global prominence, there exists a scarcity of information regarding its prevalence and distribution in South Africa. Thus, this study used laboratory records to investigate the serotype diversity, temporal distribution, and seasonal patterns of A. pleuropneumoniae isolated from porcine samples spanning from 1985 to 2023 within South Africa. Data from laboratory registries of 354 cases, obtained from three veterinary laboratories in South Africa, were analyzed. The data were categorized into two-time frames: term 1, covering 1985 to 2001, and term 2, spanning from 2002 to 2023. The dataset identified 11 different serotypes, with serotype 7 being the most prevalent at 22.7% (n = 62), which was followed by serotype 5 at 13.8% (n = 42). The study highlighted variations in the prevalence of serotypes among diseased animals over a 38-year period. Serotypes 3, 5, 7 and 8 were commonly observed during this time, while serotype 4 was absent from 1985 to 2001, and serotypes 1, 6, and 10 were absent from 2002 to 2023. The distribution of serotypes showed a diverse variation in the age of affected animals, clinical manifestation, and seasonal occurrence. Key findings revealed that serotype 7 was the most prevalent across all seasons with the highest occurrence in winter. Additionally, Gauteng province showed the highest prevalence of various serotypes. The information collected during this study will serve as a baseline for future epidemiological studies as well as inform control strategies.
Collapse
Affiliation(s)
- Emmanuel M. Seakamela
- Bacteriology Division, Agricultural Research Council, Onderstepoort Veterinary Research, Pretoria 0110, South Africa
| | - Marijke M. Henton
- Vetdiagnostix Veterinary Pathology Services, P.O. Box 13624, Cascades 3202, South Africa;
| | - Annelize Jonker
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Pretoria 0110, South Africa;
| | - Prudence N. Kayoka-Kabongo
- Department of Agriculture and Animal Health, College of Agriculture and Environmental Sciences, University of South Africa, Johannesburg 1710, South Africa;
| | - Itumeleng Matle
- Bacteriology Division, Agricultural Research Council, Onderstepoort Veterinary Research, Pretoria 0110, South Africa
| |
Collapse
|
2
|
Zhang K, Chu P, Song S, Yang D, Bian Z, Li Y, Gou H, Jiang Z, Cai R, Li C. Proteome Analysis of Outer Membrane Vesicles From a Highly Virulent Strain of Haemophilus parasuis. Front Vet Sci 2021; 8:756764. [PMID: 34901247 PMCID: PMC8662722 DOI: 10.3389/fvets.2021.756764] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 10/25/2021] [Indexed: 11/13/2022] Open
Abstract
Haemophilus parasuis has emerged as an important bacterial pathogen in pig husbandry, as H. parasuis can coinfect pigs with a variety of pathogenic microorganisms and further cause an aggravation of the disease. It is crucial to investigate its pathogenetic mechanism. Gram-negative bacteria naturally secrete outer membrane vesicles (OMVs), and their potent virulence factors play prominent roles that affect the interaction between bacteria and host. Still, the pathogenesis that is associated with the bacterial OMVs has not been well-elucidated. In this study, we investigated the secretion of OMVs from a clinical H. parasuis isolate strain (H45). In addition, we further analyzed the characterization, the comprehensive proteome, and the virulence potential of OMVs. Our data demonstrated that H. parasuis could secrete OMVs into the extracellular milieu during infection. Using liquid chromatography with tandem mass spectrometry (MS/MS) identification and bio-information analysis, we identified 588 different proteins associated with OMVs. Also, we also analyzed the subcellular location and biological function of those proteins. These proteins are mainly involved in immune and iron metabolism. Moreover, we confirmed the pathogenicity of H. parasuis OMVs by observing a strong inflammatory response in J774A.1 and porcine alveolar macrophages. Taken together, our findings suggested that OMVs from H. parasuis were involved in the pathogenesis of this bacterium during infection.
Collapse
Affiliation(s)
- Kunli Zhang
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Key Laboratory of Livestock Disease Prevention of Guangdong Province, Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, Guangzhou, China.,Maoming Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong, China
| | - Pinpin Chu
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Key Laboratory of Livestock Disease Prevention of Guangdong Province, Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, Guangzhou, China.,Maoming Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong, China
| | - Shuai Song
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Key Laboratory of Livestock Disease Prevention of Guangdong Province, Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, Guangzhou, China.,Maoming Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong, China
| | - Dongxia Yang
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Key Laboratory of Livestock Disease Prevention of Guangdong Province, Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, Guangzhou, China.,Maoming Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong, China
| | - Zhibiao Bian
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Key Laboratory of Livestock Disease Prevention of Guangdong Province, Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, Guangzhou, China.,Maoming Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong, China
| | - Yan Li
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Key Laboratory of Livestock Disease Prevention of Guangdong Province, Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, Guangzhou, China.,Maoming Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong, China
| | - Hongchao Gou
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Key Laboratory of Livestock Disease Prevention of Guangdong Province, Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, Guangzhou, China.,Maoming Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong, China
| | - Zhiyong Jiang
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Key Laboratory of Livestock Disease Prevention of Guangdong Province, Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, Guangzhou, China.,Maoming Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong, China
| | - Rujian Cai
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Key Laboratory of Livestock Disease Prevention of Guangdong Province, Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, Guangzhou, China.,Maoming Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong, China
| | - Chunling Li
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Key Laboratory of Livestock Disease Prevention of Guangdong Province, Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, Guangzhou, China.,Maoming Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong, China
| |
Collapse
|
3
|
Bom HA, Silva Filho GB, Silva EG, Pereira MR, Fonseca SM, Boswell R, Almeida VM, Souza FA, Mendonça FS. Glässer’s disease in swine from Northeastern Brazil. PESQUISA VETERINÁRIA BRASILEIRA 2020. [DOI: 10.1590/1678-5150-pvb-6642] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
ABSTRACT: Glässer’s disease is an important infectious disorder of swine caused by Haemophilus parasuis. Although well recognized in most regions of Brazil, outbreaks of Glässer’s disease have not been described in Northeastern region. For this reason, three municipalities of the Pernambuco State were visited in order to identify histories of high mortality in growing and finishing pigs. The main clinical signs consisted of dry cough, apathy, fever, anorexia, paresis, muscle tremors, motor incoordination, seizures leading to high mortality rates. Nine pigs were necropsied, and fragments of the nervous system, organs of the abdominal and thoracic cavities were collected for histological analysis. In addition, lung and brain fragments were used for DNA extraction and molecular testing by real-time Polymerase Chain Reaction (PCR). Grossly, the main lesions consisted of petechial hemorrhages or ecchymosis on the skin of the face, abdomen, forelimbs, and hind limbs. The main severe lesions consisted of hydropericardium, hemopericardium, fibrinous pericarditis and pleuropneumonia. Microscopically, pericarditis, epicarditis and subepicardial myocarditis, followed by a moderate to severe multifocal pleuropneumonia, fibrinosuppurative and necrotizing were the most frequent lesions observed. Real-time PCR amplified H. parasuis infB gene in all samples analyzed, confirming the presence of this etiologic agent.
Collapse
Affiliation(s)
| | | | | | | | | | - Rikki Boswell
- Western University of Health Sciences, United States
| | | | | | | |
Collapse
|
4
|
Turni C, Wu Y, Omaleki L, Giang N, Blackall PJ, Christensen H. Glaesserella australis sp. nov., isolated from the lungs of pigs. Int J Syst Evol Microbiol 2020; 70:3686-3692. [PMID: 32416742 DOI: 10.1099/ijsem.0.004221] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Twenty-nine isolates of an unknown haemophilic organism were isolated from the lungs of pigs from 14 farms in Australia. Phylogenetic analyses based on the 16S rRNA gene, recN and rpoA showed a monophyletic group that was most closely related to Glaesserella parasuis and [Actinobacillus] indolicus. Whole genome sequence analysis indicated that the Glaesserella parasuis and this group, using the type strain HS4635T for comparison, showed a similarity of 30.9 % DNA-DNA renaturation. The isolates were Gram-stain-negative, NAD-dependent, CAMP-negative and were oxidase-positive, catalase-negative and produced indole but not urease. The isolates could be separated from all currently recognized haemophilic and non-haemophilic members of the family Pastuerellaceae. Key phenotypic properties were the production of indole, the lack of urease activity, production of β-galactosidase but not α-fucosidase, acid formation from (-)-d-arabinose, (+)-d-galactose, maltose and trehalose and a failure to produce acid from (-)-d-mannitol. Taken together, these data indicate that the isolates belong to a novel species for which the name Glaesserella australis sp. nov. is proposed. The type strain is HS4635T (=CCUG 71931T and LMG 30645T).
Collapse
Affiliation(s)
- Conny Turni
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, Queensland 4067, Australia
| | - Yunchen Wu
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland 4067, Australia
| | - Lida Omaleki
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, Queensland 4067, Australia
| | - Nhan Giang
- School of Chemistry and Molecular Biosciences, 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
| | - Henrik Christensen
- Department of Veterinary and Animal Sciences, University of Copenhagen, 4 Stigbøjlen, DK-1870 Frederiksberg C, Denmark
| |
Collapse
|
5
|
Identification of Haemophilus parasuis genes uniquely expressed during infection using in vivo-induced antigen technology. Vet Microbiol 2020; 243:108650. [PMID: 32273024 DOI: 10.1016/j.vetmic.2020.108650] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 03/04/2020] [Accepted: 03/17/2020] [Indexed: 01/12/2023]
Abstract
Haemophilus parasuis is the etiological agent of Glässer's disease which is characterized by fibrinous polyserositis, arthritis and meningitis. The pathogenesis of this bacterium remains largely unknown. Genes expressed in vivo may play an important role in the pathogenicity of H. parasuis. The development of in vivo-induced antigen technology (IVIAT) has provided a valuable tool for the identification of in vivo-induced genes during bacterial infection. In this study, IVIAT was applied to identify in vivo-induced antigens of H. parasuis. Pooled swine H. parasuis-positive sera, adsorbed against in vitro-grown cultures of H. parasuis SH0165 and Escherichia coli BL21 (DE3), were used to screen the inducible expression library of genomic proteins from whole genome sequenced H. parsuis SH0165. Finally, 24 unique genes expressed in vivo were successfully identified after secondary and tertiary screening with IVIAT. These genes were implicated in cell surface proteins, metabolism, stress response, regulation, transportation and other processes. Quantitative real-time PCR showed that the mRNA levels of 24 genes were all upregulated in vivo relative to in vitro, with 13 genes were detected significantly upregulated in H. parasuis infected pigs. Several potential virulence-associated genes were found to be uniquely expressed in vivo, including espP, lnt, hutZ, mreC, vtaA, pilB, tex, sunT and aidA. The results indicated that the proteins identified using IVIAT may play important roles in the pathogenesis of H. parasuis infection in vivo.
Collapse
|
6
|
Zheng ML, Li LH, Liu B, Lin YB, Zhang XT, Chen C, Qu PH, Zeng J. Haemophilus seminalis sp. nov., isolated from human semen. Int J Syst Evol Microbiol 2020; 70:2588-2595. [PMID: 32163029 DOI: 10.1099/ijsem.0.004074] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Two Haemophilus-like isolates with similar biochemical characteristics, designated strains SZY H1T and SZY H2, were isolated from human semen specimens. Cells were Gram-negative, non-motile, non-acid-fast, pleomorphic rods or coccobacilli. The major fatty acids (>10 %) were C16 : 0, C14 : 0, iso-C16 : 0 and/or C14 : 0 3-OH and C16 : 1 ω6c and/or C16 : 1 ω7c. The polar lipids were determined to be phosphatidylethanolamine, phosphatidylglycerol, an unidentified phospholipid, an unidentified aminophospholipid, two unidentified polar lipids and four unidentified aminolipids. The major polyamine was found to be cadaverine. The near-full-length (1462 nt) 16S rRNA gene sequences analysis showed the two isolates were nearly identical (>99.8 %), and closely matched Haemophilus haemolyticus ATCC 33390T with 98.9-99.1 % sequence similarities. Phylogenetic analysis based on 16S rRNA gene sequences and concatenation of 30 protein markers also revealed that the isolates clustered together with H. haemolyticus ATCC 33390T, and formed a distinct lineage well separated from the other members of the genus Haemophilus. Further, the average nucleotide identity values between the two isolates and their related species were below the established cut-off values for species delineation (95 %). Based on these findings, the two isolates are considered to represent a new species of the genus Haemophilus, for which name Haemophilus seminalis sp. nov. is proposed. The type strain is SZY H1T (=NBRC 113782T=CGMCC 1.17137T).
Collapse
Affiliation(s)
- Min-Ling Zheng
- The Second Clinic Medical College, Guangzhou University of Chinese Medicine, Guangzhou 510006, PR China
| | - Liang-Hui Li
- The Second Clinic Medical College, Guangzhou University of Chinese Medicine, Guangzhou 510006, PR China
| | - Bin Liu
- The Second Hospital, University of South China, Hengyang 421001, PR China
| | - Yu-Bo Lin
- Department of Clinical Laboratory, Wuchuan Maternity and Child Health Care Hospital, Wuchuan 524500, PR China
| | - Xiao-Tuan Zhang
- The Second Hospital, University of South China, Hengyang 421001, PR China
| | - Cha Chen
- Department of Clinical Laboratory, Guangdong Provincial Hospital of Traditional Chinese Medicine, Guangzhou 510006, PR China.,The Second Clinic Medical College, Guangzhou University of Chinese Medicine, Guangzhou 510006, PR China
| | - Ping-Hua Qu
- The Second Clinic Medical College, Guangzhou University of Chinese Medicine, Guangzhou 510006, PR China.,Department of Clinical Laboratory, Guangdong Provincial Hospital of Traditional Chinese Medicine, Guangzhou 510006, PR China
| | - Jian Zeng
- The Second Hospital, University of South China, Hengyang 421001, PR China
| |
Collapse
|
7
|
Draft Genome Sequences of the Type Strains of Actinobacillus indolicus (46K2C) and Actinobacillus porcinus (NM319), Two NAD-Dependent Bacterial Species Found in the Respiratory Tract of Pigs. Microbiol Resour Announc 2020; 9:9/1/e00716-19. [PMID: 31896621 PMCID: PMC6940273 DOI: 10.1128/mra.00716-19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We report here the draft genome sequences of the type strains of Actinobacillus indolicus (46K2C) and Actinobacillus porcinus (NM319). These NAD-dependent bacterial species are frequently found in the upper respiratory tract of pigs and are occasionally associated with lung pathology. We report here the draft genome sequences of the type strains of Actinobacillus indolicus (46K2C) and Actinobacillus porcinus (NM319). These NAD-dependent bacterial species are frequently found in the upper respiratory tract of pigs and are occasionally associated with lung pathology.
Collapse
|
8
|
Costa-Hurtado M, Garcia-Rodriguez L, Lopez-Serrano S, Aragon V. Haemophilus parasuis VtaA2 is involved in adhesion to extracellular proteins. Vet Res 2019; 50:69. [PMID: 31547880 PMCID: PMC6755704 DOI: 10.1186/s13567-019-0687-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 08/23/2019] [Indexed: 12/11/2022] Open
Abstract
Haemophilus parasuis is part of the microbiota of the upper respiratory tract in swine. However, virulent strains can cause a systemic disease known as Glässer’s disease. Several virulence factors have been described in H. parasuis including the virulence-associated trimeric autotransporters (VtaAs). VtaA2 is up-regulated during infection and is only found in virulent strains. In order to determine its biological function, the vtaA2 gene was cloned with its native promotor region in pACYC184, and the transformed Escherichia coli was used to perform functional in vitro assays. VtaA2 was found to have a role in attachment to plastic, mucin, BSA, fibronectin and collagen. As other VtaAs from H. parasuis, the passenger domain of VtaA2 contains collagen domains. In order to examine the contribution of the collagen repeats to VtaA2 function, a recombinant vtaA2 without the central collagen domains was obtained and named vtaA2OL. VtaA2OL showed similar capacity than VtaA2 to adhere to plastic, mucin, BSA, fibronectin and plasma but a reduced capacity to adhere to collagen, suggesting that the collagen domains of VtaA2 are involved in collagen attachment. No function in cell adhesion and invasion to epithelial alveolar cell line A549 or unspecific binding to primary alveolar macrophages was found. Likewise VtaA2 had no role in serum or phagocytosis resistance. We propose that VtaA2 mediates adherence to the host by binding to the mucin, found in the upper respiratory tract mucus, and to the extracellular matrix proteins, present in the connective tissue of systemic sites, such as the serosa.
Collapse
Affiliation(s)
- Mar Costa-Hurtado
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain.
| | - Laura Garcia-Rodriguez
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain
| | - Sergi Lopez-Serrano
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain
| | - Virginia Aragon
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain
| |
Collapse
|
9
|
Li XD, Chi SQ, Wu LY, Liu C, Sun T, Hong J, Chen X, Chen XG, Wang GS, Yu DJ. PK/PD modeling of Ceftiofur Sodium against Haemophilus parasuis infection in pigs. BMC Vet Res 2019; 15:272. [PMID: 31370843 PMCID: PMC6676638 DOI: 10.1186/s12917-019-2008-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Accepted: 07/16/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Ceftiofur Sodium is widely used in China. Our aim was to determine Ceftiofur Sodium activity and optimize dosing regimens against the pathogen Haemophilus parasuis using an in vitro and ex vivo pharmacokinetics/pharmacodynamics modeling approach. By adopting these strategies, we wanted to extend the effective life of Ceftiofur Sodium in reduce drug-resistance in pigs. RESULTS We established an H. parasuis infection model in pigs, and assessed the pharmacokinetics of Ceftiofur Sodium in both healthy and infected animals. After Ceftiofur Sodium (10 mg/kg, i.m.) administration to healthy and H. parasuis-infected pigs, plasma based desfuroylceftiofur (a metabolite of Ceftiofur Sodium) was measured by High Performance Liquid Chromatography. The pharmacokinetics of Ceftiofur Sodium (desfuroylceftiofur) was consistent with a two-compartment open model, with first-order absorption. We observed no significant differences (P > 0.05) in pharmacokinetic parameters between healthy and infected pigs. Pharmacodynamics data showed that Ceftiofur Sodium was highly inhibitory against H. parasuis, with MIC, MBC, and MPC values of 0.003125, 0.0125 and 0.032 μg/mL, respectively. Desfuroylceftiofur in plasma also had strong bactericidal activity. Almost all H. parasuis cultured in plasma medium of Ceftiofur Sodium-inoculated healthy pigs, at each time point, were killed within 24 h. A weaker antibacterial activity was measured in infected-pig plasma medium at 18, 24, 36, and 48 h, after Ceftiofur Sodium inoculation. Pharmacokinetic parameters were combined with ex vivo pharmacodynamic parameters, and the bacteriostatic effect (36.006 h), bactericidal effect (71.637 h) and clearance (90.619 h) within 24 h, were determined using the Hill equation. Dose-calculation equations revealed the optimal dose of Ceftiofur Sodium to be 0.599-1.507 mg/kg. CONCLUSIONS There were no significant differences in Ceftiofur Sodium pharmacokinetic parameters between healthy and infected pigs, although pharmacokinetics/pharmacodynamics fitting curves showed obviously differences. The optimal dose of Ceftiofur Sodium was lower than recommended (3 mg/kg), which may provide improved treatments for Glässers disease, with lower drug-resistance possibility.
Collapse
Affiliation(s)
- Xiao-Dong Li
- Fujian Key Laboratory of Traditional Chinese Veterinary Medicine and Animal Health, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Sheng-Qing Chi
- Fujian Key Laboratory of Traditional Chinese Veterinary Medicine and Animal Health, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Li-Yun Wu
- Fujian Key Laboratory of Traditional Chinese Veterinary Medicine and Animal Health, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Can Liu
- Fujian Key Laboratory of Traditional Chinese Veterinary Medicine and Animal Health, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Tong Sun
- Fujian Key Laboratory of Traditional Chinese Veterinary Medicine and Animal Health, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Juan Hong
- Fujian Key Laboratory of Traditional Chinese Veterinary Medicine and Animal Health, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Xun Chen
- Fujian Key Laboratory of Traditional Chinese Veterinary Medicine and Animal Health, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Xiao-Gang Chen
- Fujian Key Laboratory of Traditional Chinese Veterinary Medicine and Animal Health, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Guan-Song Wang
- Fujian Key Laboratory of Traditional Chinese Veterinary Medicine and Animal Health, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Dao-Jin Yu
- Fujian Key Laboratory of Traditional Chinese Veterinary Medicine and Animal Health, Fujian Agriculture and Forestry University, Fuzhou, China.
| |
Collapse
|
10
|
Dai K, Yang Z, Chang YF, He L, Cao S, Zhao Q, Huang X, Wu R, Huang Y, Yan Q, Han X, Ma X, Wen X, Wen Y. Construction of targeted and integrative promoter-reporter plasmids pDK-K and pDK-G to measure gene expression activity in Haemophilus parasuis. Microb Pathog 2019; 134:103565. [PMID: 31158493 DOI: 10.1016/j.micpath.2019.103565] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 04/10/2019] [Accepted: 05/31/2019] [Indexed: 10/26/2022]
Abstract
Haemophilus parasuis (H. parasuis) is rather difficult to manipulate genetically due to the diversity of restriction-modification systems and other mechanisms harbored by various isolates. This prevents exogenous plasmids from replicating in this species and hinders research efforts focused on transcriptional regulators in this bacterium. In this study, we generated a convenient promoter reporter system based on gene knock-in method using natural transformation in H. parasuis. Gene knock-in has proven useful as a powerful tool facilitating identification and studying the transcription activities of regulators under a variety of conditions that favor gene transcription or expression from an incorporated promoter. The vectors, pDK-K and pDK-G, carrying promoterless reporter lacZ gene and two homologous sequences flanking a knock-in site, may have some advantages over the extensively used plasmid-bearing reporter system in other bacteria in stability and ease of genetic manipulation in H. parasuis. The knock-in site was positioned at a site occupied by flanking genes that were both hypothetical and had the same transcription orientation, thus the expression of the reversely cloned promoter-lacZ fusion wouldn't be affected by the upstream promoter on the chromosome. The expression activity of lacZ gene under the transcriptional activation of a 300 bp promoter-proximal segment of cyaA, crp or comA genes in H. parasuis was separately validated using X-gal and o-nitrophenyl-β-d-galactoside(ONPG) as substrates. The derivatives harboring promoter-lacZ fusion segments showed significantly higher β-galactosidase activity levels than the promoterlessones both in TSB++ broth and on TSA++ plate as screened either by X-gal method or the standard Miller method. We also used pDK vector to further certify that the cyaA promoter is inducible and whose transcriptional levels were in correlation with the growth kinetics of the bacteria in TSB++. With this system, gene knock-in method based on natural transformation in H. parasuis proved to be useful in identifying transcriptional regulation of a certain promoter.
Collapse
Affiliation(s)
- Ke Dai
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Zhen Yang
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Yung-Fu Chang
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, NY, USA
| | - Lvqin He
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Sanjie Cao
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Qin Zhao
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xiaobo Huang
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Rui Wu
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Yong Huang
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Qigui Yan
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xinfeng Han
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xiaoping Ma
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xintian Wen
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Yiping Wen
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.
| |
Collapse
|
11
|
Lin WH, Shih HC, Lin CF, Yang CY, Lin CN, Chiou MT. Genotypic analyses and virulence characterization of Glaesserella parasuis isolates from Taiwan. PeerJ 2019; 7:e6960. [PMID: 31149406 PMCID: PMC6526895 DOI: 10.7717/peerj.6960] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 04/16/2019] [Indexed: 11/21/2022] Open
Abstract
Background Glaesserella (Haemophilus) parasuis (G. parasuis) causes severe economic losses in the swine industry. Multiple G. parasuis strains can exist in single animals. Typing techniques are required for identifying G. parasuis isolates. Different strains within a serovar display varying virulence. Enterobacterial repetitive intergenic consensus polymerase chain reaction (ERIC-PCR) can assess the heterogeneity. The group 1 virulence-associated trimeric autotransporters (vtaA) gene is an indicator of virulence. The aim of this study was to characterize Taiwanese G. parasuis isolates via molecular serotyping, vtaA PCR and ERIC-PCR. Methods One hundred and forty-five strains were collected between November 2013 and March 2017 in Taiwan and further examined by molecular serotyping, vtaA PCR and ERIC-PCR. Results The dendrogram revealed heterogeneous genetic diversity within many clusters. Partial correlation between the ERIC-PCR clusters of different strains, serovars and lesion patterns was observed. Twelve herds (8.3%) infected with more than one strain. Group 1 vtaA positive rate reached 98.6%. Discussion This study showed the high genetic diversity of G. parasuis in Taiwan by a high discriminatory capability of ERIC-PCR. Group 1 vtaA commonly exists in G. parasuis isolates and may play important roles in the pathogenesis of Taiwanese G. parasuis isolates.
Collapse
Affiliation(s)
- Wei-Hao Lin
- Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan.,Animal Disease Diagnostic Center, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Hsing-Chun Shih
- Animal Disease Diagnostic Center, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Chuen-Fu Lin
- Department of Veterinary Medicine, College of Veterinary Medicine, National Chiayi University, Chiayi, Taiwan
| | - Cheng-Yao Yang
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, Taichung, Taiwan
| | - Chao-Nan Lin
- Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan.,Animal Disease Diagnostic Center, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Ming-Tang Chiou
- Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan.,Animal Disease Diagnostic Center, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan.,Research Center for Animal Biologics, National Pingtung University of Science and Technology, Pingtung, Taiwan
| |
Collapse
|
12
|
Lin WH, Shih HC, Lin CF, Yang CY, Chang YF, Lin CN, Chiou MT. Molecular serotyping of Haemophilus parasuis isolated from diseased pigs and the relationship between serovars and pathological patterns in Taiwan. PeerJ 2018; 6:e6017. [PMID: 30519512 PMCID: PMC6275120 DOI: 10.7717/peerj.6017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 10/26/2018] [Indexed: 11/20/2022] Open
Abstract
Background Haemophilus parasuis is the etiological agent of Glässer’s disease, and causes severe economic losses in the swine industry. Serovar classification is intended as an indicator of virulence and pathotype and is also crucial for vaccination programs and vaccine development. According to a polysaccharide biosynthesis locus analysis, H. parasuis isolates could be classified by a molecular serotyping assay except serovars 5 and 12 detected by the same primer pair. The aim of this study was to identify H. parasuis isolates from diseased pigs in Taiwan by using a molecular serotyping assay and to analyze the relationship between serovars and pathological patterns. Methods From August 2013 to February 2017, a total of 133 isolates from 277 lesions on 155 diseased animals from 124 infected herds serotyped by multiplex PCR and analyzed with pathological data. Results The dominant serovars of H. parasuis in Taiwan were serovars 5/12 (37.6%), 4 (27.8%) and 13 (15%) followed by molecular serotyping non-typable (MSNT) isolates (13.5%). Nevertheless, the serovar-specific amplicons were not precisely the same sizes as previously indicated in the original publication, and MSNT isolates appeared with unexpected amplicons or lacked serovar-specific amplicons. Most H. parasuis isolates were isolated from nursery pigs infected with porcine reproductive and respiratory syndrome virus. The percentage of lung lesions (30.4%) showing H. parasuis infection was significantly higher than that of serosal lesions. Discussion Collectively, the distribution of serovars in Taiwan is similar to that found in other countries, but MSNT isolates remain due to genetic variations. Furthermore, pulmonary lesions may be optimum sites for H. parasuis isolation, the diagnosis of Glässer’s disease, and may also serve as points of origin for systemic H. parasuis infections in hosts.
Collapse
Affiliation(s)
- Wei-Hao Lin
- Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan.,Animal Disease Diagnostic Center, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Hsing-Chun Shih
- Animal Disease Diagnostic Center, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Chuen-Fu Lin
- Department of Veterinary Medicine, College of Veterinary Medicine, National Chiayi University, Chiayi, Taiwan
| | - Cheng-Yao Yang
- Graduate Institute of Veterinary Pathobiology, College of Veterinary Medicine, National Chung Hsing University, Taichung, Taiwan
| | - Yung-Fu Chang
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, NY, USA
| | - Chao-Nan Lin
- Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan.,Animal Disease Diagnostic Center, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Ming-Tang Chiou
- Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan.,Animal Disease Diagnostic Center, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan.,Research Center for Animal Biologics, National Pingtung University of Science and Technology, Pingtung, Taiwan
| |
Collapse
|
13
|
OxyR of Haemophilus parasuis is a global transcriptional regulator important in oxidative stress resistance and growth. Gene 2018; 643:107-116. [DOI: 10.1016/j.gene.2017.12.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 12/05/2017] [Accepted: 12/07/2017] [Indexed: 11/17/2022]
|
14
|
Cao Q, Feng F, Wang H, Xu X, Chen H, Cai X, Wang X. Haemophilus parasuis CpxRA two-component system confers bacterial tolerance to environmental stresses and macrolide resistance. Microbiol Res 2017; 206:177-185. [PMID: 29146255 DOI: 10.1016/j.micres.2017.10.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 10/17/2017] [Accepted: 10/20/2017] [Indexed: 11/29/2022]
Abstract
Haemophilus parasuis is an opportunistic pathogen localized in the upper respiratory tracts of pigs, its infection begins from bacterial survival under complex conditions, like hyperosmosis, oxidative stress, phagocytosis, and sometimes antibiotics as well. The two-component signal transduction (TCST) system serves as a common stimulus-response mechanism that allows microbes to sense and respond to diverse environmental conditions via a series of phosphorylation reactions. In this study, we investigated the role of TCST system CpxRA in H. parasuis in response to different environmental stimuli by constructing the ΔcpxA and ΔcpxR single deletion mutants as well as the ΔcpxRA double deletion mutant from H. parasuis serotype 4 isolate JS0135. We demonstrated that H. parasuis TCST system CpxRA confers bacterial tolerance to stresses and bactericidal antibiotics. The CpxR was found to play essential roles in mediating oxidative stress, osmotic stresses and alkaline pH stress tolerance, as well as macrolide resistance (i.e. erythromycin), but the CpxA deletion did not decrease bacterial resistance to abovementioned stresses. Moreover, we found via RT-qPCR approach that HAPS_RS00160 and HAPS_RS09425, both encoding multidrug efflux pumps, were significantly decreased in erythromycin challenged ΔcpxR and ΔcpxRA mutants compared with wild-type strain JS0135. These findings characterize the role of the TCST system CpxRA in H. parasuis conferring stress response tolerance and bactericidal resistance, which will deepen our understanding of the pathogenic mechanism in H. parasuis.
Collapse
Affiliation(s)
- Qi Cao
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Fenfen Feng
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Huan Wang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Xiaojuan Xu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Huanchun Chen
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China
| | - Xuwang Cai
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
| | - Xiangru Wang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China.
| |
Collapse
|
15
|
Ma L, Wang L, Chu Y, Li X, Cui Y, Chen S, Zhou J, Li C, Lu Z, Liu J, Liu Y. Characterization of Chinese Haemophilus parasuis Isolates by Traditional Serotyping and Molecular Serotyping Methods. PLoS One 2016; 11:e0168903. [PMID: 28005999 PMCID: PMC5179118 DOI: 10.1371/journal.pone.0168903] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 12/08/2016] [Indexed: 11/18/2022] Open
Abstract
Haemophilus parasuis is classified mainly through serotyping, but traditional serotyping always yields non-typable (NT) strains and unreliable results via cross-reactions. Here, we surveyed the serotype prevalence of Chinese H. parasuis isolates using traditional serotyping (gel immuno-diffusion test, GID) and molecular serotyping (multiplex PCR, mPCR). We also investigated why discrepant results between these methods were obtained, and investigated mPCR failure through whole-genome sequencing. Of the 100 isolate tested, 73 (73%) and 93 (93%) were serotyped by the GID test and mPCR, respectively, with a concordance rate of 66% (66/100). Additionally, mPCR reduced the number of NT isolates from 27 (27%) for the GID testing, to seven (7%). Eleven isolates were sequenced, including nine serotype-discrepant isolates from mPCR and GID typing (excluding strains that were NT by GID only) and two NT isolates from both methods, and their in silico serotypes were obtained from genome sequencing based on their capsule loci. The mPCR results were supported by the in silico serotyping of the seven serotype-discrepant isolates. The discrepant results and NT isolates determined by mPCR were attributed to deletions and unknown sequences in the serotype-specific region of each capsule locus. Compared with previous investigations, this study found a similar predominant serotype profile, but a different prevalence frequency for H. parasuis, and the five most prevalent serotypes or strain groups were serotypes 5, 4, NT, 7 and 13 for mPCR, and serotypes 5, NT, 4, 7 and 13/10/14 for GID. Additionally, serotype 7 was recognized as a principal serotype in this work.
Collapse
Affiliation(s)
- Lina Ma
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu, China
| | - Liyan Wang
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu, China
| | - Yuefeng Chu
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu, China
| | - Xuerui Li
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu, China
| | - Yujun Cui
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Shengli Chen
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu, China
| | - Jianhua Zhou
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu, China
| | - Chunling Li
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, Guangdong, China
| | - Zhongxin Lu
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu, China
| | - Jixing Liu
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu, China
| | - Yongsheng Liu
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu, China
- * E-mail:
| |
Collapse
|
16
|
Zhao L, Gao X, Liu C, Lv X, Jiang N, Zheng S. Deletion of the vacJ gene affects the biology and virulence in Haemophilus parasuis serovar 5. Gene 2016; 603:42-53. [PMID: 27988234 DOI: 10.1016/j.gene.2016.12.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Revised: 10/28/2016] [Accepted: 12/10/2016] [Indexed: 12/31/2022]
Abstract
Haemophilus parasuis is an important pathogen causing severe infections in pigs. However, the specific bacterial factors that participate in pathogenic process are poorly understood. VacJ protein is a recently discovered outer membrane lipoprotein that relates to virulence in several pathogens. To characterize the function of the vacJ gene in H. parasuis virulent strain HS49, a vacJ gene-deletion mutant ΔvacJ and its complemented strain were constructed. Our findings supported that VacJ is essential for maintenance of cellular integrity and stress tolerance of H. parasuis, by the demonstrations that the ΔvacJ mutant showed morphological change, increased NPN fluorescence and, and decreased resistance to SDS-EDTA, osmotic and oxidation pressure. The increased susceptibility to several antibiotics in the ΔvacJ mutant further suggested that the stability of the outer membrane was impaired as a result of the mutation in the vacJ gene. Compared to the wild-type strain, the ΔvacJ mutant strain caused a decreased survival ratio from the serum and complement killing, and exhibited a significant decrease ability to adhere to and invade PK-15 cell. In addition, the ΔvacJ mutant showed reduced biofilm formation compared to the wild-type strain. Furthermore, the ΔvacJ was attenuated in a murine (Balb/C) model of infection and its LD50 value was approximately fifteen-fold higher than that of the wild-type or complementation strain. The data obtained in this study indicate that vacJ plays an essential role in maintaining outer membrane integrity, stress tolerance, biofilm formation, serum resistance, and adherence to and invasion of host cells related to H. parasuis and further suggest a putative role of VacJ lipoprotein in virulence regulation.
Collapse
Affiliation(s)
- Liangyou Zhao
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, People's Republic of China; Drug Safety Evaluation Center of Heilongjiang University of Chinese Medicine, Harbin 150040, People's Republic of China
| | - Xueli Gao
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, People's Republic of China
| | - Chaonan Liu
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, People's Republic of China
| | - Xiaoping Lv
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, People's Republic of China
| | - Nan Jiang
- College of Life Science and Technology, Dalian University, Dalian 116622, People's Republic of China
| | - Shimin Zheng
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, People's Republic of China.
| |
Collapse
|
17
|
Chen Y, Liu T, Langford P, Hua K, Zhou S, Zhai Y, Xiao H, Luo R, Bi D, Jin H, Zhou R. Haemophilus parasuis induces activation of NF-κB and MAP kinase signaling pathways mediated by toll-like receptors. Mol Immunol 2015; 65:360-6. [PMID: 25733389 DOI: 10.1016/j.molimm.2015.02.016] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Revised: 02/05/2015] [Accepted: 02/11/2015] [Indexed: 12/20/2022]
Abstract
Glässer's disease in pigs caused by Haemophilus parasuis is characterized by a severe membrane inflammation. In our previous study, we have identified activation of the transcription factor NF-κB after H. parasuis infection of porcine epithelial cells. In this study, we found that H. parasuis infection also contributed to the activation of p38/JNK MAPK pathway predominantly linked to inflammation, but not the ERK MAPK pathway associated with growth, differentiation and development. Inhibition of NF-κB, p38 and JNK but not ERK activity significantly reduced IL-8 and CCL4 expression by H. parasuis. We also found TLR1, TLR2, TLR4 and TLR6 were required for NF-κB, p38 and JNK MAPK activation. Furthermore, MyD88 and TRIF signaling cascades were essential for H. parasuis-induced NF-κB activation. These results provided new insights into the molecular pathways underlying the inflammatory response induced by H. parasuis.
Collapse
Affiliation(s)
- Yushan Chen
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Ting Liu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Paul Langford
- Section of Paediatrics, Imperial College London, St Mary's Campus, London W2 1PG, UK
| | - Kexin Hua
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Shanshan Zhou
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Yajun Zhai
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Hongde Xiao
- Hubei Center for Animal Disease Control and Prevention, Wuhan 430070, China
| | - Rui Luo
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Dingren Bi
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Hui Jin
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
| | - Rui Zhou
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| |
Collapse
|
18
|
Identification of putative virulence-associated genes among Haemophilus parasuis strains and the virulence difference of different serovars. Microb Pathog 2014; 77:17-23. [PMID: 25283960 DOI: 10.1016/j.micpath.2014.10.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2014] [Revised: 09/29/2014] [Accepted: 10/01/2014] [Indexed: 11/24/2022]
Abstract
This study was aimed at determining virulence-associated genes among Haemophilus parasuis (H. parasuis) strains, and supplying for the Kielstein-Rapp-Gabrielson serotyping scheme. The subtractive fragments, obtained through suppression subtractive hybridization and reverse Southern blot hybridization, were found to encode genes representative of 7 different functions. PCR was used to investigate the distribution of these fragments in H. parasuis strains isolated from different infection sites in pigs. Mice challenge was then used to analyze the correlationship between subtractive fragments, infection sites and bacterial virulence. Eight weeks old female BALB/c mice (10 mice/group) were inoculated intraperitoneally with 3.0 × 10(9) CFU suspension (0.5 ml/mouse) of H. parasuis strains in PBS. Results indicated that H. parasuis possessed varied virulence even among the same serovar strains. Transcription units hsdR, hsdS, gpT and ompP2, identified from the subtractive fragments, were uniformly expressed in highly virulent strains, while absent in weakly virulent strains, and demonstrated variable degrees of expression in moderately virulent strains. Moreover, H. parasuis strains, isolated from pericardium and heart blood, were all highly virulent strains, while from nasal cavity and joint were moderately or weakly virulent strains. This study indicated that fragments hsdR, hsdS, gpT and ompP2 were associated with the virulence of H. parasuis. The virulence of H. parasuis strains isolated from different infection sites was different. The current research provides a new reference for determining bacterial virulence in different H. parasuis strains.
Collapse
|
19
|
Costa-Hurtado M, Aragon V. Advances in the quest for virulence factors of Haemophilus parasuis. Vet J 2013; 198:571-6. [DOI: 10.1016/j.tvjl.2013.08.027] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Revised: 08/20/2013] [Accepted: 08/25/2013] [Indexed: 10/26/2022]
|
20
|
Frandoloso R, Pivato M, Martínez-Martínez S, Rodríguez-Ferri EF, Kreutz LC, Martín CBG. Differences in Haemophilus parasuis adherence to and invasion of AOC-45 porcine aorta endothelial cells. BMC Vet Res 2013; 9:207. [PMID: 24119995 PMCID: PMC3852208 DOI: 10.1186/1746-6148-9-207] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 10/08/2013] [Indexed: 11/22/2022] Open
Abstract
Background The pathogenesis of Haemophilus parasuis depends on the bacterium’s ability to interact with endothelial cells and invade adjacent tissues. In this study, we investigated the abilities of eight H. parasuis reference strains belonging to serovars 1, 2, 4, 5, 7, 9, 10 and 13 to adhere to and invade porcine aortic endothelial cells (AOC-45 cell line). Results The strains belonging to serovars 1, 2 and 5 were able to attach at high rates between 60 and 240 min of incubation, and serovars 4, 7 and 13 had moderate attachment rates; however, the strains belonging to serovars 9 and 10 had low adherence at all time points. Strong adherence was observed by scanning electron microscopy for the strains of serovars 5 and 4, which had high and moderate numbers, respectively, of H. parasuis cells attached to AOC-45 cells after 240 min of incubation. The highest invasiveness was reached at 180 min by the serovar 4 strain, followed by the serovar 5 strain at 240 min. The invasion results differed substantially depending on the strain. Conclusion The reference strains of H. parasuis serovars 1, 2, 4 and 5 exhibited high adhesion and invasion levels to AOC-45 porcine aorta endothelial cells, and these findings could aid to better explain the pathogenesis of the disease caused by these serovars.
Collapse
Affiliation(s)
- Rafael Frandoloso
- Section of Microbiology and Immunology, Department of Animal Health, University of León, León, Spain.
| | | | | | | | | | | |
Collapse
|
21
|
Frandoloso R, Martínez-Martínez S, Rodríguez-Ferri E, Gutiérrez-Martín C. Comparison of real-time PCR and culture isolation in colostrum-deprived pigs immunized and challenged with Haemophilus parasuis. Lett Appl Microbiol 2011; 54:149-52. [DOI: 10.1111/j.1472-765x.2011.03187.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
22
|
Martínez-Martínez S, Frandoloso R, Gutiérrez-Martín CB, Lampreave F, García-Iglesias MJ, Pérez-Martínez C, Rodríguez-Ferri EF. Acute phase protein concentrations in colostrum-deprived pigs immunized with subunit and commercial vaccines against Glässer's disease. Vet Immunol Immunopathol 2011; 144:61-7. [DOI: 10.1016/j.vetimm.2011.07.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Revised: 06/29/2011] [Accepted: 07/08/2011] [Indexed: 01/14/2023]
|
23
|
Frandoloso R, Martínez-Martínez S, Gutiérrez-Martín CB, Rodríguez-Ferri EF. Haemophilus parasuis serovar 5 Nagasaki strain adheres and invades PK-15 cells. Vet Microbiol 2011; 154:347-52. [PMID: 21839589 DOI: 10.1016/j.vetmic.2011.07.022] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Revised: 07/13/2011] [Accepted: 07/19/2011] [Indexed: 10/17/2022]
Abstract
Haemophilus parasuis is the agent responsible for causing Glässer's disease, which is characterized by fibrinous polyserositis, polyarthritis and meningitis in pigs. The purpose of this study was to investigate the in vitro ability of two H. parasuis serovars of different virulence (serovar 5, Nagasaki strain, highly virulent, belonging to serovar 5, and SW114 strain, nonvirulent, belonging to serovar 3) to adhere to and invade porcine kidney epithelial cells (PK-15 line). Nagasaki strain was able to attach at high levels from 60 to 180 min of incubation irrespective of the concentrations compared (10(7)-10(10)CFU), and a substantial increase of surface projections could be seen in PK-15 cells by scanning electron microscopy. This virulent strain was also able to invade effectively these epithelial cells, and the highest invasion capacity was reached at 180 min of infection. On the contrary, nonvirulent SW114 strain hardly adhered to PK-15 cells, and it did not invade these cells, thus suggesting that adherence and invasion of porcine kidney epithelial cells could be a virulence mechanism involved in the lesions caused by H. parasuis Nagasaki strain in this organ.
Collapse
Affiliation(s)
- Rafael Frandoloso
- Section of Microbiology and Immunology, Department of Animal Health, University of León, 24007 León, Spain
| | | | | | | |
Collapse
|
24
|
Multiplex PCR assay for detection of Actinobacillus pleuropneumoniae, Pasteurella multocida and Haemophilus parasuis in lungs of pigs from a slaughterhouse. Folia Microbiol (Praha) 2011; 55:635-40. [PMID: 21253912 DOI: 10.1007/s12223-010-0103-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2010] [Revised: 06/21/2010] [Indexed: 10/18/2022]
Abstract
Multiplex PCR has been developed for parallel identification of Actinobacillus pleuropneumoniae, Pasteurella multocida and Haemophilus parasuis, important pathogens of swine, responsible for considerable economic losses in swine industry. Multiplex PCR and bacteriological cultivation was used to analyze lung samples from slaughterhouse pigs. From a total of 219 lung samples, 164 (74.9 %) were positive for P. multocida, 45 (20.5 %) for A. pleuropneumoniae and 4 (1.83 %) for H. parasuis. Bacteriological examination revealed that 145 samples (66.2 %) were positive for P. multocida, 31 (14.2 %) for A. pleuropneumoniae and 2 (0.91 %) for H. parasuis.
Collapse
|
25
|
Olvera A, Pina S, Macedo N, Oliveira S, Aragon V, Bensaid A. Identification of potentially virulent strains of Haemophilus parasuis using a multiplex PCR for virulence-associated autotransporters (vtaA). Vet J 2011; 191:213-8. [PMID: 21247786 DOI: 10.1016/j.tvjl.2010.12.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Revised: 11/19/2010] [Accepted: 12/11/2010] [Indexed: 10/18/2022]
Abstract
Haemophilus parasuis is the aetiological agent of Glässer's disease and is also a commensal of the upper respiratory tract of pigs. Trimeric autotransporter (vtaA) genes have been identified in H. parasuis and divided into three groups on the basis of the translocator domain sequence. In this study, group 3 vtaA genes were demonstrated by PCR in all 157 H. parasuis isolates tested. Group 1 vtaA genes were associated with virulent strains; 52/54 (96%) group 1 vtaA negative field isolates were isolated from the nasal passages of healthy animals, whereas no group 1 vtaA negative field isolates were isolated from cases of Glässer's disease. There was an association between absence of group 1 vtaA, sensitivity to phagocytosis and serum and classification of isolates into nasal cluster C by multilocus sequence typing. A multiplex PCR was developed for diagnosis of H. parasuis at the species level (group 3 vtaA positive) and to differentiate putative non-virulent strains (group 1 vtaA negative). When applied to field samples, the PCR confirmed a high prevalence of H. parasuis in conventionally farmed pigs and demonstrated that almost half of the animals carried potentially virulent strains.
Collapse
Affiliation(s)
- Alex Olvera
- Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
| | | | | | | | | | | |
Collapse
|
26
|
Lowe BA, Marsh TL, Isaacs-Cosgrove N, Kirkwood RN, Kiupel M, Mulks MH. Microbial communities in the tonsils of healthy pigs. Vet Microbiol 2011; 147:346-57. [DOI: 10.1016/j.vetmic.2010.06.025] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2010] [Revised: 06/23/2010] [Accepted: 06/24/2010] [Indexed: 10/19/2022]
|
27
|
Sow vaccination modulates the colonization of piglets by Haemophilus parasuis. Vet Microbiol 2010; 145:315-20. [DOI: 10.1016/j.vetmic.2010.04.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2010] [Revised: 03/31/2010] [Accepted: 04/08/2010] [Indexed: 11/21/2022]
|
28
|
Correlation between clinico-pathological outcome and typing of Haemophilus parasuis field strains. Vet Microbiol 2010; 142:387-93. [DOI: 10.1016/j.vetmic.2009.10.025] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Revised: 10/21/2009] [Accepted: 10/26/2009] [Indexed: 11/21/2022]
|
29
|
Aragon V, Bouchet B, Gottschalk M. Invasion of endothelial cells by systemic and nasal strains of Haemophilus parasuis. Vet J 2009; 186:264-7. [PMID: 19748806 DOI: 10.1016/j.tvjl.2009.08.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2009] [Revised: 08/07/2009] [Accepted: 08/07/2009] [Indexed: 10/20/2022]
Abstract
Haemophilus parasuis is a respiratory commensal in healthy piglets, but can also produce invasive disease and meningitis, which requires the ability to cross the blood-brain barrier. This study determined the capacity of well-characterised virulent and non-virulent strains of H. parasuis, as well as other field strains, to adhere to and invade PBMEC/C1-2 endothelial cells. Virulent strains were derived from systemic lesions, conformed to the systemic clade on multilocus sequence typing (MLST) and were phagocytosis- and serum-resistant. Non-virulent strains were derived from the nostrils of healthy piglets, belonged to the nasal clade on MLST and were phagocytosis- and serum-sensitive. Virulent strains mostly were more invasive than non-virulent strains, although one virulent strain was unable to invade. Invasion of endothelial cells is a virulence mechanism of H. parasuis that may be related to the ability of some strains to cause meningitis.
Collapse
Affiliation(s)
- Virginia Aragon
- Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
| | | | | |
Collapse
|
30
|
Cerdà-Cuéllar M, Aragon V. Serum-resistance in Haemophilus parasuis is associated with systemic disease in swine. Vet J 2008; 175:384-9. [PMID: 17368943 DOI: 10.1016/j.tvjl.2007.01.016] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2006] [Revised: 01/09/2007] [Accepted: 01/22/2007] [Indexed: 11/27/2022]
Abstract
Haemophilus parasuis can cause pneumonia and systemic disease in swine but it is also a coloniser of the upper respiratory tract of healthy pigs. These differences in pathogenicity are probably the result of diverse mechanisms of virulence in different strains. Since serum-resistance is a feature frequently found in systemic pathogens, 31 H. parasuis strains of different clinical origin were tested and a variety of serum susceptibility levels detected. Nasal strains from healthy piglets were sensitive to the bactericidal effect of the serum, while systemic strains were mainly resistant. The pulmonary strains included both serum-sensitive and serum-resistant strains. Interestingly, the serum-resistant pulmonary strains were isolated from animals with systemic lesions. Heat-treatment of the sera abolished the bactericidal activity, indicating that complement is a key factor in this effect. Equivalent susceptibility was observed with rabbit and porcine sera, and the presence of H. parasuis specific antibodies did not increase the killing of the strains by serum. In an attempt to associate serum-resistance to a surface determinant of the bacteria, agglutination in acriflavine was tested but no direct link with serum susceptibility was found. The results indicate that serum-resistance is a virulence mechanism in H. parasuis.
Collapse
Affiliation(s)
- Marta Cerdà-Cuéllar
- Centre de Recerca en Sanitat Animal (CReSA), Campus de Bellaterra-Universitat, Autònoma de Barcelona, Barcelona, Spain
| | | |
Collapse
|
31
|
Olvera A, Cerdà-Cuéllar M, Mentaberre G, Casas-Diaz E, Lavin S, Marco I, Aragon V. First isolation of Haemophilus parasuis and other NAD-dependent Pasteurellaceae of swine from European wild boars. Vet Microbiol 2007; 125:182-6. [PMID: 17574352 DOI: 10.1016/j.vetmic.2007.05.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2007] [Revised: 05/03/2007] [Accepted: 05/10/2007] [Indexed: 12/01/2022]
Abstract
Haemophilus parasuis is a colonizer of the upper respiratory tract of pigs and the etiological agent of Glässer's disease, which is characterized by a fibrinous polyserositis, meningitis and arthritis. Glässer's disease has never been reported in wild boar (Sus scrofa), although antibodies against H. parasuis have been detected. The goal of this study was to confirm the presence of this bacterium in wild boar by bacterial isolation and to compare the strains to H. parasuis from domesticated pigs. Therefore, nasal swabs from 42 hunted wild boars were processed for bacterial isolation and subsequent H. parasuis identification by specific PCR, biochemical tests and 16S rRNA gene sequencing. Two different strains of H. parasuis from two wild boars were isolated. These strains belonged to serotype 2 and were included by 16S rRNA gene sequencing and MLST analysis in a cluster with other H. parasuis strains of nasal origin from domestic pigs. During this study, Actinobacillus minor and Actinobacillus indolicus, which are NAD-dependent Pasteurellaceae closely related to H. parasuis, were also isolated. Our results indicate similarities in the respiratory microbiota of wild boars and domestic pigs, and although H. parasuis was isolated from wild boars, more studies are needed to determine if this could be a source of H. parasuis infection for domestic pigs.
Collapse
Affiliation(s)
- A Olvera
- Centre de Recerca en Sanitat Animal (CReSA), Esfera UAB, Edifici CReSA, Campus de Bellaterra-UAB, 08193 Bellaterra, Barcelona, Spain
| | | | | | | | | | | | | |
Collapse
|
32
|
Olvera A, Segalés J, Aragón V. Update on the diagnosis of Haemophilus parasuis infection in pigs and novel genotyping methods. Vet J 2006; 174:522-9. [PMID: 17175186 DOI: 10.1016/j.tvjl.2006.10.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2006] [Revised: 09/15/2006] [Accepted: 10/20/2006] [Indexed: 11/24/2022]
Abstract
Haemophilus parasuis causes Glässer's disease as well as a number of other diseases in pigs. The diagnosis of H. parasuis-associated disease is usually established by clinical signs, pathological findings and bacterial isolation but diagnosis is complicated by the existence of non-virulent strains and the early colonisation of the upper respiratory tract of healthy piglets. Moreover, several strains can be found on a farm and even within a single animal so it is important to determine the specific strain that is causing the clinical outbreak. Recently, genotyping methods have been developed with the goal of correlating genotype with the degree of virulence of H. parasuis strains. The association between genotype and virulence in H. parasuis is challenging due to the lack of knowledge of the complete genomic sequence and virulence factors of this bacterium.
Collapse
Affiliation(s)
- Alex Olvera
- Centre de Recerca en Sanitat Animal (CReSA), Campus de Bellaterra, Universitat Autònoma de Barcelona, Barcelona, Spain
| | | | | |
Collapse
|
33
|
Angen O, Oliveira S, Ahrens P, Svensmark B, Leser TD. Development of an improved species specific PCR test for detection of Haemophilus parasuis. Vet Microbiol 2006; 119:266-76. [PMID: 17113728 DOI: 10.1016/j.vetmic.2006.10.008] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2006] [Revised: 09/28/2006] [Accepted: 10/06/2006] [Indexed: 11/19/2022]
Abstract
A PCR test for identification of Haemophilus parasuis was optimized using the 16S rDNA sequences of the 15 serotype reference strains of H. parasuis. The test was evaluated on a collection of 218 Danish field isolates as well as on 81 representatives of 27 other species, including genetically affiliated species within Pasteurellaceae. In addition, DNA preparations from 56 H. parasuis isolates from North America were included. To obtain a test that was specific for H. parasuis, a multiplex PCR using 3 different primers was developed. The PCR test produced an amplicon of approximately 1090 bp only with representatives of H. parasuis. The test was further evaluated on 55 clinical samples from 16 Danish pigs suspected for being infected with H. parasuis, showing polyserositis or septicemia at autopsy as well as on 492 nasal swabs. The test was compared with the performance of a PCR test earlier published by Oliveira et al. [Oliveira, S., Galina, L., Pijoan, C., 2001. Development of a PCR test to diagnose Haemophilus parasuis infections. J. Vet. Diagn. Invest. 13, 495-501]. The sensitivity of the present PCR test was found to be slightly lower when applied on clinical samples from diseased pigs and 10-fold lower when tested on pure cultures of H. parasuis (5CFU and 0.5CFU/PCR reaction, respectively). Addition of 1.4 x 10(5) Escherichia coli to each PCR tube did not alter the sensitivity of the tests. No difference in sensitivity of the tests was observed when tested on purified DNA. On the other hand, the present PCR test was found to be 100% species specific for H. parasuis, in contrast to the PCR test of Oliveira et al., which also tested positive for strains belonging to A. indolicus, A. porcinus, and A. minor, species commonly occurring in the upper respiratory tract. However, when the PCR test of Oliveira et al. is used on samples from systemic locations the chances for false positive results are apparently low. The present PCR test represents a rapid and reliable method for genetically based identification of H. parasuis. The high species specificity of the test makes it suitable for detection of H. parasuis in clinical samples, regardless of the presence of affiliated species and contaminating flora. As the two PCR tests differ in sensitivity and specificity, the use of both PCR tests for different purposes is a possibility.
Collapse
Affiliation(s)
- Oystein Angen
- Danish Institute for Food and Veterinary Research, Bülowsvej 27, DK-1790 Copenhagen, Denmark.
| | | | | | | | | |
Collapse
|
34
|
Olvera A, Calsamiglia M, Aragon V. Genotypic diversity of Haemophilus parasuis field strains. Appl Environ Microbiol 2006; 72:3984-92. [PMID: 16751506 PMCID: PMC1489591 DOI: 10.1128/aem.02834-05] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Haemophilus parasuis is the cause of Glässer's disease and other clinical disorders in pigs. It can also be isolated from the upper respiratory tracts of healthy pigs, and isolates can have significant differences in virulence. In this work, a partial sequence from the 60-kDa heat shock protein (Hsp60) gene was assessed as an epidemiological marker. We analyzed partial sequences of hsp60 and 16S rRNA genes from 103 strains of H. parasuis and other related species to obtain a better classification of the strains and examine the correlation with virulence. The results were compared with those obtained by enterobacterial repetitive intergenic consensus PCR. Our results showed that hsp60 is a reliable marker for epidemiological studies of H. parasuis and that the analysis of its sequence is a better approach than fingerprinting methods. Furthermore, the analysis of the hsp60 and 16S rRNA gene sequences revealed the presence of a separate lineage of virulent strains and indicated the occurrence of lateral gene transfer among H. parasuis and Actinobacillus strains.
Collapse
Affiliation(s)
- A Olvera
- Centre de Recerca en Sanitat Animal (CReSA), Campus de Bellaterra, Universitat Autònoma de Barcelona, 08193-Bellaterra, Barcelona, Spain
| | | | | |
Collapse
|
35
|
Vanier G, Szczotka A, Friedl P, Lacouture S, Jacques M, Gottschalk M. Haemophilus parasuis invades porcine brain microvascular endothelial cells. MICROBIOLOGY-SGM 2006; 152:135-142. [PMID: 16385123 DOI: 10.1099/mic.0.28312-0] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Haemophilus parasuis, an important swine pathogen, is the aetiological agent of Glässer's disease. It is responsible for cases of polyserositis, meningitis and pneumonia in young pigs. To date, 15 serotypes have been described, although several non-typable isolates are frequently recovered from diseased animals. The pathogenesis of H. parasuis infection is poorly understood. To cause meningitis, H. parasuis would have to cross the blood-brain barrier (BBB), composed of brain microvascular endothelial cells (BMEC). The objective of this study was to investigate the ability of H. parasuis to interact with porcine brain microvascular endothelial cells (PBMEC). It was demonstrated that the serotype 5 reference strain of H. parasuis, Nagasaki (originally recovered from a case of meningitis), was able to adhere at very high levels to and, most importantly, invade PBMEC. These capacities were confirmed by electron microscopy. Actinobacillus pleuropnemoniae serotype 7 (strain WF 83), used as negative control, was not able to adhere to or invade PBMEC. Comparisons of the levels of adhesion and invasion by several H. parasuis field strains from different serotypes isolated from cases of either meningitis or pneumonia showed that isolates of serotypes 4 and 5 had a higher invasion capacity than isolates belonging to other serotypes. Inhibition studies demonstrated that PBMEC invasion by H. parasuis required rearrangement of actin microfilaments and microtubular cytoskeletal elements but not active bacterial DNA, RNA or protein synthesis. Characterization studies demonstrated that proteinaceous invasin(s) does not seem to play a major role in entry of H. parasuis into PBMEC. Intracellular viable H. parasuis were found in PBMEC up to 6 h after antibiotic treatment. Even at high bacterial doses, H. parasuis was not toxic to PBMEC. In swine, the invasion of endothelial cells of the BBB may play an important role in the pathogenesis of meningitis caused by H. parasuis.
Collapse
Affiliation(s)
- Ghyslaine Vanier
- Groupe de Recherche sur les Maladies Infectieuses du Porc (GREMIP), Faculté de Médecine Vétérinaire, Université de Montréal, Québec, Canada
| | - Anna Szczotka
- Canadian Research Network on Bacterial Pathogens of Swine, Faculté de Médecine Vétérinaire, Université de Montréal, Québec, Canada
| | - Peter Friedl
- Institute für Biochemie, Technische Hochschule Darmstadt, Petersenstrasse 22, 64287 Darmstadt, Germany
| | - Sonia Lacouture
- Groupe de Recherche sur les Maladies Infectieuses du Porc (GREMIP), Faculté de Médecine Vétérinaire, Université de Montréal, Québec, Canada
| | - Mario Jacques
- Canadian Research Network on Bacterial Pathogens of Swine, Faculté de Médecine Vétérinaire, Université de Montréal, Québec, Canada
- Groupe de Recherche sur les Maladies Infectieuses du Porc (GREMIP), Faculté de Médecine Vétérinaire, Université de Montréal, Québec, Canada
| | - Marcelo Gottschalk
- Canadian Research Network on Bacterial Pathogens of Swine, Faculté de Médecine Vétérinaire, Université de Montréal, Québec, Canada
- Groupe de Recherche sur les Maladies Infectieuses du Porc (GREMIP), Faculté de Médecine Vétérinaire, Université de Montréal, Québec, Canada
| |
Collapse
|
36
|
Tadjine M, Mittal KR, Bourdon S, Gottschalk M. Development of a new serological test for serotyping Haemophilus parasuis isolates and determination of their prevalence in North America. J Clin Microbiol 2004; 42:839-40. [PMID: 14766867 PMCID: PMC344452 DOI: 10.1128/jcm.42.2.839-840.2004] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Haemophilus parasuis causes polyserositis in swine. Fifteen serovars have been characterized by immunodiffusion test, but many field strains are not typeable. Isolates (n = 300) of H. parasuis from animals in North America were serotyped by a new indirect hemagglutination test. The test was rapid and effective for serotyping of H. parasuis, and serovars 4, 5, 13, and 7 were the most prevalent serotypes.
Collapse
Affiliation(s)
- M Tadjine
- Département de Pathologie et Microbiologie, Faculté de Médecine Vétérinaire, Université de Montréal, Sainte-Hyacinthe, Québec, Canada J2S 7C6
| | | | | | | |
Collapse
|
37
|
Oliveira S, Pijoan C. Haemophilus parasuis: new trends on diagnosis, epidemiology and control. Vet Microbiol 2004; 99:1-12. [PMID: 15019107 DOI: 10.1016/j.vetmic.2003.12.001] [Citation(s) in RCA: 236] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2003] [Revised: 08/04/2003] [Indexed: 11/26/2022]
Abstract
Haemophilus parasuis is a commensal organism of the upper respiratory tract of conventional pigs, but under appropriate conditions can invade and cause severe systemic disease, characterized by fibrinous polyserositis, arthritis and meningitis. Factors involved in systemic invasion by H. parasuis remain largely unknown. However, major advances in our knowledge of H. parasuis include (1) development of a species-specific PCR test to detect H. parasuis in clinical samples, (2) study of molecular epidemiology within and between herds, by use of a repetitive element-based PCR, (3) the proposal of an alternative serotyping technique, (4) development and testing of a new in vivo model for pathogenesis and virulence studies, and (5) use of controlled exposure of young pigs to low doses of live, virulent H. parasuis strains to reduce nursery mortality in affected swine herds.
Collapse
Affiliation(s)
- Simone Oliveira
- Department of Clinical and Population Sciences, College of Veterinary Medicine, University of Minnesota, 385 Animal Science/Veterinary Medicine, 1988 Fitch Avenue, Saint Paul, MN 55108, USA.
| | | |
Collapse
|
38
|
Hamer-Barrera R, Godínez D, Enríquez VI, Vaca-Pacheco S, Martinez-Zúñiga R, Talamás-Rohana P, Suárez-Güemez F, de la Garza M. Adherence of actinobacillus pleuropneumoniae serotype 1 to swine buccal epithelial cells involves fibronectin. CANADIAN JOURNAL OF VETERINARY RESEARCH = REVUE CANADIENNE DE RECHERCHE VETERINAIRE 2004; 68:33-41. [PMID: 14979433 PMCID: PMC1142127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
The swine pathogen Actinobacillus pleuropneumoniae serotype 1 was investigated for its ability to adhere to swine, rat, and human buccal epithelial cells (BEC). The highest number of bacteria adhered was to swine BEC. This binding ability was affected by heating, extreme pH, treatment with sodium dodecyl sulfate, ethylenediamine tetra-acetate, or periodate, and proteolysis, suggesting that cell-surface glycoproteins participate in adherence and that adherence is based mostly on ionic interactions. Mannose and swine fibronectin may play a direct role in this interaction. Convalescent-phase serum from naturally infected pigs inhibited the adhesion. There was a correlation between bacterial pathogenicity as well as host specificity and the capacity for adherence to swine BEC. Adhesion to swine BEC provides a convenient method to study in vitro the adherence of A. pleuropneumoniae and other pathogens of the pig respiratory tract.
Collapse
Affiliation(s)
- Roberto Hamer-Barrera
- Departamento de Biología Celular, Centro de Investigación y de Estudios Avanzados del IPN, Ap. postal 14-740, México DF 07000, México
| | | | | | | | | | | | | | | |
Collapse
|
39
|
Gottschalk M, Broes A, Mittal KR, Kobisch M, Kuhnert P, Lebrun A, Frey J. Non-pathogenic Actinobacillus isolates antigenically and biochemically similar to Actinobacillus pleuropneumoniae: a novel species? Vet Microbiol 2003; 92:87-101. [PMID: 12488073 DOI: 10.1016/s0378-1135(02)00341-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Two unusual Actinobacillus isolates were recovered from pigs with no clinical signs, no lesions and no history of swine pleuropneumonia. Two representative strains (9953L55 and 0347) analyzed in this study were initially biochemically and antigenically identified as A. pleuropneumoniae serotypes 1 and 9, respectively, by traditional identification methods. Both strains presented, however, negative results with three A. pleuropneumoniae-specific PCR tests and revealed in particular the absence of the apxIV toxin genes. However, both strains produced and secreted ApxII toxin although they only harbored the toxin genes apxIICA, which is an uncommon feature for any of the known A. pleuropneumoniae serotypes. Upon experimental inoculation of pigs, these strains proved to be totally non-pathogenic. Animals infected with one of the strains produced antibodies that cross-react with A. pleuropneumoniae serotypes 1-9-11-specific LC-LPS ELISA. Phylogenetic analysis based on 16S rRNA gene sequence analysis revealed that these strains form a separate phylogenetic group that is distinct from other Actinobacillus species and is particularly different from A. pleuropneumoniae.
Collapse
Affiliation(s)
- M Gottschalk
- Groupe de Recherche sur les Maladies Infectieuses du Porc (GREMIP), Département de Pathologie et Microbiologie, Faculté de médecine vétérinaire, Université de Montréal, C.P. 5000, St-Hyacinthe, Quebec, Canada J2S 7C6.
| | | | | | | | | | | | | |
Collapse
|
40
|
Kielstein P, Wuthe H, Angen O, Mutters R, Ahrens P. Phenotypic and genetic characterization of NAD-dependent Pasteurellaceae from the respiratory tract of pigs and their possible pathogenetic importance. Vet Microbiol 2001; 81:243-55. [PMID: 11390108 DOI: 10.1016/s0378-1135(01)00351-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Nicotinamide adenine dinucleotide (NAD)-dependent Pasteurellaceae other than Actinobacillus pleuropneumoniae and Haemophilus parasuis are frequently isolated from the respiratory tract of pigs. The taxonomic classification and relevance for pathogenicity of these bacteria deserves further attention. In the present study, 107 of these NAD-dependent isolates from the porcine respiratory tract, primarily from lungs with pathological changes, were investigated. On the basis of phenotypic criteria, such as haemolysis, urease, catalase, and indole formation as well as other fermentative activities, 50 of the isolates were assigned to Actinobacillus minor, 36 isolates to Actinobacillus porcinus and 21 isolates to Actinobacillus indolicus. However, many isolates among the three species showed fermentative activities differing from those of the respective type strain of the species. Serotyping on the basis of heat-stable polysaccharide antigens and 16 rDNA sequencing also revealed substantial heterogeneity within each of the three species although they clustered together in three distinct groups in the phylogenetic analysis. These three groups of NAD-dependent bacteria are different from, or in a borderline position, to the existing species or genera within the family Pasteurellaceae. A considerable number of isolates of these three groups were isolated in pure cultures from pneumonic lungs. Consequently, it will be necessary to critically review the opinion, that these NAD-dependent Pasteurellaceae are only "agents colonizing the mucosa". Further, taxonomic examinations of the strains within these three groups are indispensable to testing isolates for their virulence in gnotobiotic pigs.
Collapse
Affiliation(s)
- P Kielstein
- Federal Institute for Health Protection of Consumers and Veterinary Medicine, Division 4, Jena, Naumburger Str. 96a, D-07743, Jena, Germany.
| | | | | | | | | |
Collapse
|
41
|
Takahashi K, Naga S, Yagihashi T, Ikehata T, Nakano Y, Senna K, Maruyama T, Murofushi J. A cross-protection experiment in pigs vaccinated with Haemophilus parasuis serovars 2 and 5 bacterins, and evaluation of a bivalent vaccine under laboratory and field conditions. J Vet Med Sci 2001; 63:487-91. [PMID: 11411491 DOI: 10.1292/jvms.63.487] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Cross-protection between Haemophilus parasuis serovars 2 and 5 was examined in pigs using a bacterin based vaccine, and subsequently the safety and efficacy of a bivalent vaccine were evaluated. Upon intratracheal challenge of a serovar 2 or 5 strain, pigs immunized with a monovalent vaccine were protected against challenge with a homologous serovar strain, but not with a heterologous serovar strain. Immunization with a bivalent vaccine containing both serovars 2 and 5 bacterins conferred protection in pigs against lethal challenge with each of the serovar strains. A total of 86 pigs from two SPF herds were injected with the bivalent vaccine intramuscularly twice at a four-week interval. No adverse reactions following the vaccination were observed. On day 7 after the second vaccination, vaccinated and non-vaccinated control pigs from herd A were transferred to herd B, where Glasser's disease had broken out. Pigs in the control group developed clinical signs of the disease, and 6 of 8 (75%) pigs died until slaughter, in contrast with only 4 of 46 (9%) pigs in the vaccinated group. In herd C, where there was no outbreak of Glasser's disease, complement fixation antibody titer was raised only in the vaccinated group. A challenge experiment on days 20 and 79 after the second vaccination showed that only the vaccinated pigs were protected. From these findings, the safety and efficacy of the bivalent vaccine were confirmed under laboratory and field conditions.
Collapse
Affiliation(s)
- K Takahashi
- Nippon Institute for Biological Science, Ome, Tokyo, Japan
| | | | | | | | | | | | | | | |
Collapse
|
42
|
Angen O, Heegaard PM, Lavritsen DT, Sørensen V. Isolation of Actinobacillus pleuropneumoniae serotype 2 by immunomagnetic separation. Vet Microbiol 2001; 79:19-29. [PMID: 11230926 DOI: 10.1016/s0378-1135(00)00338-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In Denmark porcine pleuropneumonia is most frequently caused by Actinobacillus pleuropneumoniae serotype 2 (60%). Isolation of A. pleuropneumoniae from nasal cavities or tonsils from carrier animals is complicated due to the mixed bacterial flora present. An immunomagnetic separation technique (IMS) using immunomagnetic beads (Dynabeads((R))) was developed for isolation of A. pleuropneumoniae serotype 2 from pure cultures and from heterogeneous suspensions. Different coating and washing procedures were evaluated in pure and mixed cultures using polyclonal (PAb) and monoclonal antibodies. The highest reisolation yield was achieved when the beads were coated with 1.5 microg PAb IgG/10(7) beads. After washing the beads for four times 9-24% of the bacteria could be reisolated depending on the amount of IgG attached to the beads and the number of beads used. The recovery was increased to 19-61% when only two washing steps were performed. The IMS was further evaluated using dilutions of A. pleuropneumoniae with added Pasteurella multocida (10(9) CFU/ml). After two washing steps 15% of the A. pleuropneumoniae cells and no P. multocida was reisolated. A detection limit of 10 CFU/ml was found in this heterogeneous suspension. No significant difference was observed when comparing the recovery of A. pleuropneumoniae from pure culture, from mixed cultures and from artificially inoculated tonsils. From 12 pigs inoculated with an aerosol of A. pleuropneumoniae serotype 2 the bacterium could not be detected from the nasal cavity or tonsils by cultivation or PCR 6 weeks later. By using IMS A. pleuropneumoniae serotype 2 could be reisolated from the tonsils of three pigs. The IMS method represents a valuable tool for isolation of A. pleuropneumoniae from tissue samples.
Collapse
Affiliation(s)
- O Angen
- Danish Veterinary Laboratory, Bülowsvej 27, DK-1790, Copenhagen V, Denmark. ang.svs.dk
| | | | | | | |
Collapse
|
43
|
Chiers K, Haesebrouck F, Mateusen B, Van Overbeke I, Ducatelle R. Pathogenicity of Actinobacillus minor, Actinobacillus indolicus and Actinobacillus porcinus strains for gnotobiotic piglets. JOURNAL OF VETERINARY MEDICINE. B, INFECTIOUS DISEASES AND VETERINARY PUBLIC HEALTH 2001; 48:127-31. [PMID: 11315522 DOI: 10.1046/j.1439-0450.2001.00433.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The purpose of the study was to evaluate the clinical significance of Actinobacillus minor, Actinobacillus porcinus and Actinobacillus indolicus strains in gnotobiotic piglets. Twenty-two 6-h-old Caesarean-delivered and colostrum-deprived piglets were intranasally and orally inoculated with 2 x 10(6) colony-forming units of an A. minor (group 2; n = 9), A. indolicus (group 3; n = 5), or A. porcinus (group 4; n = 8) strain. Six other piglets were inoculated in the same way with phosphate-buffered saline solution and used as controls (group 1). All pigs were observed for clinical signs and rectal temperatures were taken until euthanasia 7 days after inoculation. At necropsy, conchae, tonsils, lungs, brains, liver, spleen and kidneys were macroscopically examined for lesions and samples were taken for bacteriology. None of the pigs developed fever. Mild ataxia was observed in one pig from group 3 for 2 days. Clinical signs were not observed in the other animals. In none of the animals were macroscopic lesions detected at necropsy. NAD-dependent Pasteurellaceae were not isolated from control animals (group 1). The A. minor, A. indolicus and A. porcinus strains were isolated from the tonsils of one, two and one pigs, respectively. Actinobacillus porcinus was isolated from the brains of the pig with central nervous symptoms and from the conchae of another pig. The inoculation strains were not demonstrated in the other samples. It was concluded that, using these inoculation routes and dose, the A. minor, A. indolicus and A. porcinus strains had low capacity to colonize the upper respiratory tract of gnotobiotic piglets and demonstrated low or no pathogenicity in such animals.
Collapse
Affiliation(s)
- K Chiers
- Department of Pathology, Bacteriology and Poultry Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium
| | | | | | | | | |
Collapse
|
44
|
Angen O, Jensen J, Lavritsen DT. Evaluation of 5' nuclease assay for detection of Actinobacillus pleuropneumoniae. J Clin Microbiol 2001; 39:260-5. [PMID: 11136780 PMCID: PMC87711 DOI: 10.1128/jcm.39.1.260-265.2001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Sequence detection by the 5' nuclease TaqMan assay uses online detection of internal fluorogenic probes in closed PCR tubes. Primers and probe were chosen from a part of the omlA gene common to all serotypes of Actinobacillus pleuropneumoniae, which gave an amplicon of 92 bp. The test was evaluated with 73 lung isolates and 120 tonsil isolates of A. pleuropneumoniae as well as with a collection of reference strains. By using a C(t) value (cycle number in which the fluorescence exceeds the threshold defined by the software) of 30 as the cutoff limit, the 5' nuclease assay represents a test with 100% sensitivity and 100% specificity. A high degree of reproducibility of the test was demonstrated. If samples with C(t) values of </=30 are considered positive, the detection limit of the assay was 1 CFU/reaction tube, corresponding to a 10-fold higher number of DNA templates. After cycle 30, nonspecific reactions appeared when testing dilutions of DNA templates or pure cultures of A. pleuropneumoniae, as well as when testing tonsil scrapings from specific-pathogen-free herds. The diagnostic sensitivity, as evaluated with 586 tonsil scrapings from animals infected with A. pleuropneumoniae, is the same level as that of a PCR test based on the omlA gene described previously. The 5' nuclease assay represents a fast method for species-specific detection and identification of A. pleuropneumoniae in pure and mixed cultures. The evaluation shows, however, that a C(t) value cutoff limit of </=30 must be chosen in order to obtain reliable results. The investigation emphasizes that a thorough evaluation of the criteria used to define a positive test result is necessary.
Collapse
Affiliation(s)
- O Angen
- Danish Veterinary Laboratory, DK-1790 Copenhagen V, Denmark.
| | | | | |
Collapse
|
45
|
Kich J, Piffer I, Barcellos D, Guidoni A, Klein C, Fávero M, Vizotto R. Comparação de métodos de isolamento de bactérias NAD-dependentes do trato respiratório superior de suínos sadios. ARQ BRAS MED VET ZOO 2000. [DOI: 10.1590/s0102-09352000000100001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Secreções nasais, tonsilares e tecido tonsilar foram coletados de 67 leitões de 9 a 15 semanas de idade, provenientes de três rebanhos positivos para Actinobacillus pleuropneumoniae (App), e de 50 leitões provenientes de dois rebanhos negativos. Foram classificados como positivos aqueles rebanhos com isolamento prévio de sorotipos 3, 5 e 7 e rebanhos negativos aqueles submetidos a controle veterinário, sem notificação de sintomas clínicos, lesões de pleuropneumonia suína e sem isolamento do agente. O material coletado foi submetido a três diferentes métodos de cultivo: 1- semeadura direta em meio de cultivo sólido seletivo; 2- diluição em caldo seletivo seguido de subsemeadura em meio de cultivo sólido seletivo; 3- diluição em caldo seletivo seguido de subsemeadura em ágar sangue. Entre as amostras NAD-dependentes recuperadas 86 foram classificadas como App, 13 como grupo minor e 21 como grupo taxon (C, D, E e F). Dos rebanhos positivos foram recuperadas quatro amostras de App (sorotipos 3, 7 e 12) e 51 não sorotipificáveis. Dos rebanhos negativos foram recuperadas 31 amostras de App não sorotipificáveis, indicando que o App faz parte da flora normal do trato respiratório superior dos suínos. O melhor método de isolamento de amostras NAD-dependentes de leitões portadores foi da biópsia de tecido tonsilar semeado diretamente em meio sólido seletivo (PPLO ágar adicionado de 2mi g de cristal violeta, 10mi g NAD, 1mi g de lincomicina, 1,4mi g de bacitracina por ml).
Collapse
Affiliation(s)
- J.D. Kich
- URCAMP; Universidade Federal do Rio Grande do Sul
| | | | | | | | | | | | | |
Collapse
|
46
|
Wongnarkpet S, Pfeiffer DU, Morris RS, Fenwick SG. An on-farm study of the epidemiology of Actinobacillus pleuropneumoniae infection in pigs as part of a vaccine efficacy trial. Prev Vet Med 1999; 39:1-11. [PMID: 10081784 DOI: 10.1016/s0167-5877(98)00146-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Thirty cohort pigs were followed from birth to slaughter to study epidemiological patterns of porcine pleuropneumonia caused by Actinobacillus pleuropneumoniae. The study was conducted within a larger 380-animal study of vaccination against Mycoplasma hyopneumoniae and A. pleuropneumoniae in a 340-sow farrow-to-finish piggery with 4-month weaning, operating a continuous system of intensive production in the North Island of New Zealand. The cohort pigs were randomly allocated into two equal groups: vaccinated and control. Pigs in the first group were vaccinated at 2 and 4 weeks of age with both M. hyopneumoniae vaccine and A. pleuropneumoniae vaccine at separate vaccination sites. A series of nasal swabs was taken at 4, 8, 10, 11, 12, 14, 16 and 18 weeks of age. Each swab was streaked onto the surface of a selective medium on the farm and the plates were immediately transported to a laboratory and incubated at 37 degrees C for 5 days. After the trial, pigs were slaughtered at an average of 132 days of age, lungs were examined and samples taken for bacteriological culture and isolation. Thirty-five out of 256 samples produced haemolytic colonies which were Gram-negative, V-factor-dependent and positive to the CAMP test. A. pleuropneumoniae was first isolated at 4 weeks of age from one vaccinated pig. This finding suggests that piglets became infected in the farrowing pen and the source of infection might be a carrier sow. The interval-specific cumulative incidence of A. pleuropneumoniae infection reached a maximum of 54% and 40% at 11 weeks of age in the vaccinated and control groups, respectively. Infection status of the litter is considered to be a factor influencing morbidity in infected herds during weaner and grower periods. Our results suggest that simultaneous vaccination with M. hyopneumoniae and A. pleuropneumoniae vaccines at 2 and 4 weeks of age might lessen the prevalence but cannot absolutely prevent A. pleuropneumoniae infection during the weaner or grower-finisher periods.
Collapse
Affiliation(s)
- S Wongnarkpet
- Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand
| | | | | | | |
Collapse
|
47
|
Calsamiglia M, Pijoan C, Solano G, Rapp-Gabrielson V. Development of an oligonucleotide-specific capture plate hybridization assay for detection of Haemophilus parasuis. J Vet Diagn Invest 1999; 11:140-5. [PMID: 10098685 DOI: 10.1177/104063879901100206] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
An oligonucleotide-specific capture plate hybridization assay has been developed to rapidly, specifically, and sensitively detect Haemophilus parasuis from nasal swabs. Several in vitro studies have been performed to determine the sensitivity and specificity of the test, and in vivo studies have validated this technique in pigs. Results suggest that the assay detects <100 colony-forming units/ml in a pure culture and gives a positive result when H. parasuis is present in a ratio of 1:10(3)-10(4) in a mixed culture, and the probe does not hybridize with other related species found in the upper respiratory tract. This assay is more sensitive than culture for detection of the microorganism from nasal swabs and lesions.
Collapse
Affiliation(s)
- M Calsamiglia
- Department of Clinical and Population Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul 55108, USA
| | | | | | | |
Collapse
|
48
|
Segalés J, Domingo M, Solano GI, Pijoan C. Immunohistochemical detection of Haemophilus parasuis serovar 5 in formalin-fixed, paraffin-embedded tissues of experimentally infected swine. J Vet Diagn Invest 1997; 9:237-43. [PMID: 9249161 DOI: 10.1177/104063879700900303] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
An avidin-biotin complex immunohistochemistry technique was developed to detect Haemophilus parasuis serovar 5 in experimentally infected 18-21-day-old conventional pigs, using a rabbit polyclonal antiserum. Seven of 10 intratracheally inoculated animals developed a low to medium degree of fibrinous polyserositis; meninges and pleura were the most severely affected areas. Haemophilus parasuis was recovered from 9 of 10 pigs; in 2 of them H. parasuis was isolated from tracheal swabs only. Positive immunohistochemistry results, mainly observed as free bacteria or bacteria within inflammatory cell cytoplasm in the fibrinopurulent exudate, were observed in 8 of 10 animals. Cross-reactivity with Actinobacillus pleuropneumoniae was detected but not with other gram-positive and gram-negative bacteria tested. This immunohistochemistry technique seemed to be at least as sensitive as microbiologic cultures and could be useful in studies of pathogenesis and retrospective diagnosis. However, cross-reactivity with A. pleuropneumoniae means that positive immunohistochemistry results in lung tissue from field cases would be dubious.
Collapse
Affiliation(s)
- J Segalés
- U.D. Anatomia Patològica, Facultat de Veterinaria, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | | | | | | |
Collapse
|
49
|
Jansen R, Briaire J, Kamp EM, Gielkens AL, Smits MA. The CAMP effect of Actinobacillus pleuropneumoniae is caused by Apx toxins. FEMS Microbiol Lett 1995; 126:139-43. [PMID: 7705605 DOI: 10.1111/j.1574-6968.1995.tb07407.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Actinobacillus pleuropneumoniae shows synergistic haemolysis when cocultured with Staphylococcus aureus on blood agar plates. This CAMP effect has been attributed to a discrete CAMP factor, but also to the A. pleuropneumoniae-RTX-toxins I, II, and III. We examined the CAMP effect of recombinant Escherichia coli strains that secreted each of these toxins, and of A. pleuropneumoniae mutant strains that were devoid of one or more these toxins. We found that the E. coli strains were CAMP positive, whereas the A. pleuropneumoniae strain devoid of functional toxin genes was CAMP negative. This demonstrated that the CAMP effect of A. pleuropneumoniae is caused by the toxins and that no CAMP factor per se exists.
Collapse
Affiliation(s)
- R Jansen
- Department of Molecular Biology, DLO-Institute for Animal Science and Health (ID-DLO), Lelystad, The Netherlands
| | | | | | | | | |
Collapse
|
50
|
Jansen R, Briaire J, van Geel AB, Kamp EM, Gielkens AL, Smits MA. Genetic map of the Actinobacillus pleuropneumoniae RTX-toxin (Apx) operons: characterization of the ApxIII operons. Infect Immun 1994; 62:4411-8. [PMID: 7927703 PMCID: PMC303124 DOI: 10.1128/iai.62.10.4411-4418.1994] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Actinobacillus pleuropneumoniae RTX-toxin III (ApxIII) is implicated as an important virulence factor of A. pleuropneumoniae, the causative agent of porcine pleuropneumonia. Recently, the genes coding for ApxIII (apxIIICA) of serotype 8 were cloned and characterized. The toxin appeared to be a member of the RTX-toxin family, as are the other two secreted toxins of A. pleuropneumoniae, i.e., ApxI and ApxII. In this report, we describe the cloning and sequencing of the remaining part of the ApxIII operon of serotype 8. This sequence coded for the RTX secretion proteins ApxIIIB and ApxIIID, which showed 86 and 63% similarity to ApxIB and ApxID, respectively, and 83 and 63% similarity to HlyB and HlyD of Escherichia coli, respectively. Potential functional domains, such as eight transmembrane regions and an ATP-binding cassette, were present in ApxIIIB. We examined the presence of apxIIICABD sequences in the 12 serotypes of A. pleuropneumoniae and found that these sequences were present only in serotypes 2, 3, 4, 6, and 8, the serotypes that secrete ApxIII. Comparison of the apxIIICABD gene sequences of the serotypes revealed very few serotype-specific differences. Only the C terminus of ApxIIIA of serotype 2 differed from ApxIIIA of the other serotypes. The differences were located between the glycine-rich repeats and the secretion signal. The analysis of the apxIIICABD genes completed our efforts to characterize the ApxI, ApxII, and ApxIII operons of the reference strains of the 12 serotypes of A. pleuropneumoniae. We present a complete map of the ApxI, ApxII, and ApxIII operons and discuss this in terms of gene expression and complementation and the role of the toxins in pathogenesis.
Collapse
Affiliation(s)
- R Jansen
- Department of Molecular Biology, DLO-Institute for Animal Science and Health (ID-DLO), Lelystad, The Netherlands
| | | | | | | | | | | |
Collapse
|