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Simões J, Tilley P. Decision Making in Severe Equine Asthma-Diagnosis and Monitoring. Animals (Basel) 2023; 13:3872. [PMID: 38136909 PMCID: PMC10740644 DOI: 10.3390/ani13243872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 11/22/2023] [Accepted: 12/12/2023] [Indexed: 12/24/2023] Open
Abstract
Decision making consists of gathering quality data in order to correctly assess a situation and determine the best course of action. This process is a fundamental part of medicine and is what enables practitioners to accurately diagnose diseases and select appropriate treatment protocols. Despite severe equine asthma (SEA) being a highly prevalent lower respiratory disease amongst equids, clinicians still struggle with the optimization of routine diagnostic procedures. The use of several ancillary diagnostic tests has been reported for disease identification and monitoring, but many are only suitable for research purposes or lack practicality for everyday use. The aim of this paper is to assist the equine veterinarian in the process of decision making associated with managing SEA-affected patients. This review will focus on disease diagnosis and monitoring, while also presenting a flow-chart which includes the basic data that the clinician must obtain in order to accurately identify severely asthmatic horses in their everyday routine practice. It is important to note that European and American board-certified specialists on equine internal medicine can provide assistance in the diagnosis and treatment plan of SEA-affected horses.
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Affiliation(s)
- Joana Simões
- Equine Health and Welfare Academic Division, Faculty of Veterinary Medicine, Lusófona University, Campo Grande 376, 1749-024 Lisbon, Portugal
- CIISA-Centre for Interdisciplinary Research in Animal Health, Faculty of Veterinary Medicine, University of Lisbon, 1300-477 Lisbon, Portugal;
- Associate Laboratory for Animal and Veterinary Sciences (AL4Animals), Faculty of Veterinary Medicine, University of Lisbon, 1300-477 Lisbon, Portugal
| | - Paula Tilley
- CIISA-Centre for Interdisciplinary Research in Animal Health, Faculty of Veterinary Medicine, University of Lisbon, 1300-477 Lisbon, Portugal;
- Associate Laboratory for Animal and Veterinary Sciences (AL4Animals), Faculty of Veterinary Medicine, University of Lisbon, 1300-477 Lisbon, Portugal
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El-Hage C, Gilkerson J. Chlamydia psittaci: an emerging cause of equine abortion and fatal neonatal illness in south-eastern Australia. Vet Rec 2023; 193. [PMID: 38038292 DOI: 10.1002/vetr.3739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2023]
Abstract
While well known as a zoonotic pathogen of birds, Chlamydia psittaci is less well recognised as a cause of abortion in mares and severe infection in foals. However, in the past decade it has been causing epizootics of both in south-eastern Australia, as Charles El-Hage and James Gilkerson explain.
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Affiliation(s)
- Charles El-Hage
- Centre for Equine Infectious Disease, Melbourne Veterinary School, The University of Melbourne, Australia
| | - James Gilkerson
- Centre for Equine Infectious Disease, Melbourne Veterinary School, The University of Melbourne, Australia
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El-Hage C, Legione A, Devlin J, Hughes K, Jenkins C, Gilkerson J. Equine Psittacosis and the Emergence of Chlamydia psittaci as an Equine Abortigenic Pathogen in Southeastern Australia: A Retrospective Data Analysis. Animals (Basel) 2023; 13:2443. [PMID: 37570252 PMCID: PMC10416985 DOI: 10.3390/ani13152443] [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: 06/25/2023] [Revised: 07/19/2023] [Accepted: 07/26/2023] [Indexed: 08/13/2023] Open
Abstract
Chlamydia psittaci is an important zoonotic pathogen. Although primarily a pathogen of birds, from which infection can spillover into humans and other mammalian hosts, the importance of C. psittaci as a cause of equine reproductive loss and the risk of infection to humans in contact with infected horses are increasingly being recognised in Australia and elsewhere. Despite the risks to both human and equine health, C. psittaci infection in horses is incompletely understood. This study aimed to update and summarise cases of equine psittacosis in Australia in the period 2018-2022, thus addressing a knowledge gap relating to recent cases in this country. These cases were identified from the examination of records held by state and federal veterinary authorities and from a review of published cases. A total of 31 cases were identified. Spatial and temporal trends were identified, with cases being more prevalent in winter and spring and geographically restricted to Victoria and New South Wales. The results show that cases of equine reproductive loss due to C. psittaci are consistent and ongoing and demonstrate the importance of routinely considering C. psittaci in diagnostic investigations. The need for ongoing study to better understand this important zoonotic pathogen is evident.
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Affiliation(s)
- Charles El-Hage
- Asia Pacific Centre for Animal Health, The Melbourne Veterinary School, The University of Melbourne, Parkville, VIC 3010, Australia; (A.L.); (J.D.); (J.G.)
| | - Alistair Legione
- Asia Pacific Centre for Animal Health, The Melbourne Veterinary School, The University of Melbourne, Parkville, VIC 3010, Australia; (A.L.); (J.D.); (J.G.)
| | - Joanne Devlin
- Asia Pacific Centre for Animal Health, The Melbourne Veterinary School, The University of Melbourne, Parkville, VIC 3010, Australia; (A.L.); (J.D.); (J.G.)
| | - Kristopher Hughes
- School of Agricultural, Environmental and Veterinary Sciences, Faculty of Science and Health, Charles Sturt University, Wagga Wagga, NSW 2650, Australia;
| | - Cheryl Jenkins
- Elizabeth Macarthur Agricultural Institute, NSW Department of Primary Industries, Menangle, NSW 2568, Australia;
| | - James Gilkerson
- Asia Pacific Centre for Animal Health, The Melbourne Veterinary School, The University of Melbourne, Parkville, VIC 3010, Australia; (A.L.); (J.D.); (J.G.)
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Ricard RM, Burton J, Chow-Lockerbie B, Wobeser B. Detection of Chlamydia abortus in aborted chorioallantoises of horses from Western Canada. J Vet Diagn Invest 2023:10406387231171844. [PMID: 37129380 DOI: 10.1177/10406387231171844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023] Open
Abstract
Chlamydiae are reported to cause abortion in several species, however the association between Chlamydia sp. and equine abortions is poorly understood. A zoonotic transfer event of C. psittaci from aborted equine tissues in Australia has emphasized the need to better understand the prevalence of this pathogen in equine populations. The prevalence of chlamydia in equine abortions in North America has not been investigated thoroughly. We examined 99 formalin-fixed, paraffin-embedded placental samples submitted between 2009 and 2020 from equine abortions in Western Canada using chlamydia-specific 16S rRNA conventional PCR testing; 26 of 99 submissions tested positive for chlamydial DNA. Most of these submissions (n = 17) had no final diagnosis noted on their original pathology reports. DNA sequencing identified 22 of the 26 cases as C. abortus; 21 of the 22 C. abortus-positive samples were positive on chlamydial immunohistochemistry. These findings contrast with studies in Europe that found a low prevalence of chlamydiae using similar methodology. The high prevalence of the potentially zoonotic C. abortus identified in our study suggests that more substantial biosecurity protocols may be warranted for equine foaling, abortion, and stillbirth in Western Canada to prevent zoonotic transfer of the pathogen.
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Affiliation(s)
- R Madison Ricard
- Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Jaidyn Burton
- Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Betty Chow-Lockerbie
- Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Bruce Wobeser
- Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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Ali HHM, Al-Bayati LH. Serological and Histopathological Investigation of Chlamydia abortus in Aborted Ewes in Wasit, Iraq. ARCHIVES OF RAZI INSTITUTE 2022; 77:1105-1111. [PMID: 36618285 PMCID: PMC9759238 DOI: 10.22092/ari.2022.357270.2009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 01/15/2022] [Indexed: 01/10/2023]
Abstract
Chlamydia abortus is one of the most important pathogens, which causes a marked economic loss in small ruminants, in particular sheep, worldwide. This study aimed to detect the prevalence of C. abortus in the sera of aborted ewes in Wasit province, Iraq, using the enzyme-linked immunosorbent assay (ELISA), followed by the investigation of the main histopathological alterations that occurred in some organs of the dead newborns. Out of 180 tested samples by ELISA, 32.22% of the evaluated animals showed positive reactions to IgG antibodies toward C. abortus. Concerning the titers of the infection of seropositive ewes, there were significant increases in values of moderate level of antibody titer (55.17%), compared to mild (32.76%) and severe (12.07%) levels of infection. History data showed a significant variation (P<0.05) in the existence of seropositive ewes with other field animals. However, significant increases (P<0.05) were reported in the seropositive ewes existed with goat (91.38%) and cattle (84.48%), while significant decreases (P<0.05) were observed in positive ewes found in donkeys (8.62%), horses (3.45%), and camels (0%). Regarding the histopathology results, the findings of the small intestine showed marked necrosis of intestinal villous, hyperplastic tissues, and necrosis in some mucosal glands; however, in the liver, there was small ductal proliferation with mild portal fibrosis, necrotic debris, and focal areas of hemorrhage in the parenchyma. In conclusion, the findings of this study represent the first Iraqi data concerning Chlamydial detection in aborted ewes; however, further studies in other regions and animal species are necessary to know the actual prevalence of organisms and initiate active measures for control and prevention.
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Affiliation(s)
- H. H. M Ali
- Department of Pathology, College of Medicine, Wasit University, Wasit, Iraq
| | - L. H Al-Bayati
- Department of Microbiology, College of Medicine, Wasit University, Wasit, Iraq
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Chen Y, Wang C, Mi J, Zhou Z, Wang J, Tang M, Yu J, Liu A, Wu Y. Characterization and comparison of differentially expressed genes involved in Chlamydia psittaci persistent infection in vitro and in vivo. Vet Microbiol 2021; 255:108960. [PMID: 33667981 DOI: 10.1016/j.vetmic.2020.108960] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Accepted: 12/12/2020] [Indexed: 10/22/2022]
Abstract
Chlamydia psittaci is an obligate intracellular zoonotic pathogen that can enter a persistence state in host cells. While the exact pathogenesis is not well understood, this persistence state may play an important role in chronic Chlamydia disease. Here, we assess the effects of chlamydial persistence state in vitro and in vivo by transmission electron microscopy (TEM) and cDNA microarray assays. First, IFN-γ-induced C. psittaci persistence in HeLa cells resulted in the upregulation of 68 genes. These genes are involved in protein translation, carbohydrate metabolism, nucleotide metabolism, lipid metabolism and general stress. However, 109 genes were downregulated following persistent C. psittaci infection, many of which are involved in the TCA cycle, expression regulation and transcription, protein secretion, proteolysis and transport, membrane protein, presumed virulence factor, cell division and late expression. To further study differential gene expression of C. psittaci persistence in vivo, we established an experimentally tractable mouse model of C. psittaci persistence. The C. psittaci-infected mice were gavaged with either water or amoxicillin (amox), and the results indicated that the 20 mg/kg amox-exposed C. psittaci were viable but not infectious. Differentially expressed genes (DEGs) screened by cDNA microarray were detected, and interestingly, the results showed upregulation of three genes (euo, ahpC, prmC) and downregulation of five genes (pbp3, sucB_1, oppA_4, pmpH, ligA) in 20 mg/kg amox-exposed C. psittaci, which suggests that antibiotic treatment in vivo can induce chlamydial persistence state and lead to differential gene expression. However, the discrepancy on inducers between the two models requires more research to supplement. The results may help researchers better understand survival advantages during persistent infection and mechanisms influencing C. psittaci pathogenesis or evasion of the adaptive immune response.
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Affiliation(s)
- Yuqing Chen
- Institute of Pathogenic Biology, Hengyang Medical College, University of South China, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, University of South China, Hengyang, Hunan, 421001, China; Clinical Microbiology Laboratory, Xiangtan Central Hospital, Xiangtan, 411100, China
| | - Chuan Wang
- Institute of Pathogenic Biology, Hengyang Medical College, University of South China, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, University of South China, Hengyang, Hunan, 421001, China
| | - Jing Mi
- Department of Hospital Infection and Control, The First Affiliated Hospital of University of South China, Hengyang, 421001, China
| | - Zhou Zhou
- Institute of Pathogenic Biology, Hengyang Medical College, University of South China, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, University of South China, Hengyang, Hunan, 421001, China
| | - Jianye Wang
- Institute of Pathogenic Biology, Hengyang Medical College, University of South China, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, University of South China, Hengyang, Hunan, 421001, China
| | - Manjuan Tang
- Clinical Microbiology Laboratory, Xiangtan Central Hospital, Xiangtan, 411100, China
| | - Jian Yu
- Department of Experimental Zoology, Hengyang Medical College, University of South China, Hengyang, 421001, China
| | - Anyuan Liu
- Clinical Medical Research Center, The Second Affiliated Hospital of University of South China, Hengyang, 421001, China.
| | - Yimou Wu
- Institute of Pathogenic Biology, Hengyang Medical College, University of South China, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, University of South China, Hengyang, Hunan, 421001, China.
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7
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Akter R, Sansom FM, El-Hage CM, Gilkerson JR, Legione AR, Devlin JM. A 25-year retrospective study of Chlamydia psittaci in association with equine reproductive loss in Australia. J Med Microbiol 2021; 70:001284. [PMID: 33258756 PMCID: PMC8131020 DOI: 10.1099/jmm.0.001284] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 11/03/2020] [Indexed: 12/28/2022] Open
Abstract
Introduction. Chlamydia psittaci is primarily a pathogen of birds but can also cause disease in other species. Equine reproductive loss caused by C. psittaci has recently been identified in Australia where cases of human disease were also reported in individuals exposed to foetal membranes from an ill neonatal foal in New South Wales.Hypothesis/Gap Statement. The prevalence of C. psittaci in association with equine reproductive over time and in different regions of Australia is not known.Aim. This study was conducted to detect C. psittaci in equine abortion cases in Australia using archived samples spanning 25 years.Methodology. We tested for C. psittaci in 600 equine abortion cases reported in Australia between 1994 to 2019 using a Chlamydiaceae real-time quantitative PCR assay targeting the 16S rRNA gene followed by high-resolution melt curve analysis. Genotyping and phylogenetic analysis was performed on positive samples.Results. The overall prevalence of C. psittaci in material from equine abortion cases was 6.5 %. C. psittaci-positive cases were detected in most years that were represented in this study and occurred in Victoria (prevalence of 7.6 %), New South Wales (prevalence of 3.9 %) and South Australia (prevalence of 15.4 %). Genotyping and phylogenetic analysis showed that the C. psittaci detected in the equine abortion cases clustered with the parrot-associated 6BC clade (genotype A/ST24), indicating that infection of horses may be due to spillover from native Australian parrots.Conclusion. This work suggests that C. psittaci has been a significant agent of equine abortion in Australia for several decades and underscores the importance of taking appropriate protective measures to avoid infection when handling equine aborted material.
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Affiliation(s)
- Rumana Akter
- Asia Pacific Centre for Animal Health, The Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria 3010, Australia
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Fiona M. Sansom
- Asia Pacific Centre for Animal Health, The Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Charles M. El-Hage
- Asia Pacific Centre for Animal Health, The Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - James R. Gilkerson
- Asia Pacific Centre for Animal Health, The Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Alistair R. Legione
- Asia Pacific Centre for Animal Health, The Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Joanne M. Devlin
- Asia Pacific Centre for Animal Health, The Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria 3010, Australia
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Akter R, Stent AW, Sansom FM, Gilkerson JR, Burden C, Devlin JM, Legione AR, El-Hage CM. Chlamydia psittaci: a suspected cause of reproductive loss in three Victorian horses. Aust Vet J 2020; 98:570-573. [PMID: 32830314 DOI: 10.1111/avj.13010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 07/24/2020] [Indexed: 11/28/2022]
Abstract
Chlamydia psittaci was detected by PCR in the lung and equine foetal membranes of two aborted equine foetuses and one weak foal from two different studs in Victoria, Australia. The abortions occurred in September 2019 in two mares sharing a paddock northeast of Melbourne. The weak foal was born in October 2019 in a similar geographical region and died soon after birth despite receiving veterinary care. The detection of C. psittaci DNA in the lung and equine foetal membranes of the aborted or weak foals and the absence of any other factors that are commonly associated with abortion or neonatal death suggest that this pathogen may be the cause of the reproductive loss. The detection of C. psittaci in these cases is consistent with the recent detection of C. psittaci in association with equine abortion in New South Wales. These cases in Victoria show that C. psittaci, and the zoonotic risk it poses, should be considered in association with equine reproductive loss in other areas of Australia.
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Affiliation(s)
- R Akter
- Asia Pacific Centre for Animal Health, The Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, 3010, Australia.,Department of Medicine (RMH), The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - A W Stent
- The Melbourne Veterinary School, The University of Melbourne, Werribee, Victoria, 3030, Australia
| | - F M Sansom
- Asia Pacific Centre for Animal Health, The Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - J R Gilkerson
- Asia Pacific Centre for Animal Health, The Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - C Burden
- Goulburn Valley Equine Hospital, Congupna, Victoria, 3633, Australia
| | - J M Devlin
- Asia Pacific Centre for Animal Health, The Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - A R Legione
- Asia Pacific Centre for Animal Health, The Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - C M El-Hage
- Asia Pacific Centre for Animal Health, The Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, 3010, Australia
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Manguin E, Pépin E, Boivin R, Leclere M. Tracheal microbial populations in horses with moderate asthma. J Vet Intern Med 2020; 34:986-995. [PMID: 31985115 PMCID: PMC7096658 DOI: 10.1111/jvim.15707] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 01/10/2020] [Indexed: 11/30/2022] Open
Abstract
Background There are limited data on potential dysbiosis of the airway microbiota in horses with asthma. Hypothesis/Objectives We hypothesized that the respiratory microbiota of horses with moderate asthma is altered. Our objectives were (a) to quantify tracheal bacterial populations using culture and qPCR, (2) to compare aerobic culture and qPCR, and (c) to correlate bacterial populations with bronchoalveolar lavage fluid (BALF) cytology. Animals Eighteen horses with moderate asthma from a hospital population and 10 controls. Methods Prospective case‐control study. Aerobic culture was performed on tracheal aspirates, and streptococci, Pasteurella multocida, Chlamydophila spp., Mycoplasma spp., as well as 16S (bacterial) and 18S (fungal) rRNA subunits were quantified by qPCR. Results Potential pathogens such as Streptococcus spp., Actinobacillus spp., and Pasteurellaceae were isolated from 8, 5, and 6 horses with asthma and 3, 0, and 2 controls, respectively. There was a positive correlation between Streptococcus spp. DNA and 16S rRNA gene (r ≥ 0.7, P ≤ 0.02 in both groups), but the overall bacterial load (16S) was lower in asthma (1.5 ± 1.3 versus 2.5 ± 0.8 × 104 copy/μL, P < 0.05). There was no association between microbial populations and clinical signs, tracheal mucus or BALF inflammation. Conclusions and Clinical Importance This study does not support that bacterial overgrowth is a common feature of chronic moderate asthma in horses. Lower bacterial load could suggest dysbiosis of the lower airways, either as a consequence of chronic inflammation or previous treatments, or as a perpetuating factor of inflammation.
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Affiliation(s)
- Estelle Manguin
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Université de Montréal, Quebec, Canada
| | - Elizabeth Pépin
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Université de Montréal, Quebec, Canada
| | - Roxane Boivin
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Université de Montréal, Quebec, Canada
| | - Mathilde Leclere
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Université de Montréal, Quebec, Canada
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Gough SL, Carrick J, Raidal SL, Keane S, Collins N, Cudmore L, Russell CM, Raidal S, Hughes KJ. Chlamydia psittaci infection as a cause of respiratory disease in neonatal foals. Equine Vet J 2019; 52:244-249. [PMID: 31436332 DOI: 10.1111/evj.13170] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 08/15/2019] [Indexed: 12/16/2022]
Abstract
BACKGROUND During 2016-2018, 15 critically ill neonatal foals with acute respiratory distress associated with Chlamydia psittaci infection were presented to three referral hospitals in New South Wales. Chlamydia psittaci has not previously been associated with the development of neonatal respiratory disease. OBJECTIVES To investigate and describe the clinical features and outcome of C. psittaci infection in neonatal foals. STUDY DESIGN Multicentre retrospective case series. METHODS The clinical, clinicopathological, necropsy and histological features of 15 foals with confirmed C. psittaci infection were reviewed and reported. RESULTS Thirteen foals with C. psittaci infection died or were subjected to euthanasia within 36 h of hospitalisation and two foals survived to discharge. Findings during post-mortem examination of nonsurviving foals included bronchopneumonia, pulmonary congestion, hepatic congestion and hepatic inflammation. Detection of C. psittaci was achieved using polymerase chain reaction (PCR) testing of swabs of nasal secretions (4/6) and rectal mucosa (5/7) from live foals, lung tissues of foals at necropsy (11/14) and foetal membranes (4/5). MAIN LIMITATIONS Small numbers of confirmed cases of neonatal C. psittaci infection and inconsistent sampling methods. CONCLUSIONS Chlamydia psittaci should be considered a differential diagnosis for neonatal foals with signs of severe systemic disease, including equine neonatal acute respiratory distress syndrome (EqNARDS). Chlamydia psittaci is a zoonotic pathogen and a personal protective equipment (PPE) should be worn for the management of foals with suspected or confirmed infection.
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Affiliation(s)
- S L Gough
- Veterinary Clinical Centre, School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, New South Wales, Australia
| | - J Carrick
- Equine Specialist Consulting, Scone, New South Wales, Australia
| | - S L Raidal
- Veterinary Clinical Centre, School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, New South Wales, Australia
| | - S Keane
- Dartbrook Equine Clinic, Scone, New South Wales, Australia
| | - N Collins
- Clovelly Intensive Care Unit, Scone Equine Hospital, Scone, New South Wales, Australia
| | - L Cudmore
- Clovelly Intensive Care Unit, Scone Equine Hospital, Scone, New South Wales, Australia
| | - C M Russell
- Clovelly Intensive Care Unit, Scone Equine Hospital, Scone, New South Wales, Australia
| | - S Raidal
- Veterinary Diagnostic Laboratory, School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, New South Wales, Australia
| | - K J Hughes
- Veterinary Clinical Centre, School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, New South Wales, Australia
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PRIYANKA PRIYANKA, CHAHOTA R, GUPTA S, BHARDWAJ B, SHARMA M. Detection of chlamydiae from the upper respiratory tract of healthy and diseased draught equines. THE INDIAN JOURNAL OF ANIMAL SCIENCES 2019. [DOI: 10.56093/ijans.v89i6.91100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The present investigation was conducted to study the prevalence and molecular characterization of chlamydiae associated with the respiratory infections of equines in the Sub-Himalayan region of India. Equine nasal swab samples (119) from 20 diseased and 99 apparently healthy equines were collected and tested by family Chlamydiaceae specific nested PCR based on ompA gene, besides 89 serum samples for AGPT. The molecular characterization of chlamydial species/strains was done by analyzing variation in VD II region of ompA gene. The chlamydia infections were detected in 48.74% of the nasal swabs (55% in diseased and 47.47% in apparently healthy animals) by nested PCR. Prevalence of two genetically variant strains of Chlamydia abortus and a single strain of Chlamydia psittaci was detected. AGPT showed 4.49% seropositive equines. High prevalence of chlamydiae was found among equines in the Sub-Himalayan region of India in Himachal Pradesh in both healthy and diseased equines.
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12
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Vanderstock JM, Lecours MP, Lavoie-Lamoureux A, Gottschalk M, Segura M, Lavoie JP, Jean D. Phagocytosis, bacterial killing, and cytokine activation of circulating blood neutrophils in horses with severe equine asthma and control horses. Am J Vet Res 2018; 79:455-464. [PMID: 29583047 DOI: 10.2460/ajvr.79.4.455] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate in vitro phagocytosis and bactericidal activity of circulating blood neutrophils in horses with severe equine asthma and control horses and to determine whether circulating blood neutrophils in horses with severe equine asthma have an increase in expression of the proinflammatory cytokine tumor necrosis factor (TNF)-α and the chemokine interleukin (IL)-8 and a decrease in expression of the anti-inflammatory cytokine IL-10 in response to bacteria. ANIMALS 6 horses with severe equine asthma and 6 control horses. PROCEDURES Circulating blood neutrophils were isolated from horses with severe equine asthma and control horses. Phagocytosis was evaluated by use of flow cytometry. Bactericidal activity of circulating blood neutrophils was assessed by use of Streptococcus equi and Streptococcus zooepidemicus as targets, whereas the cytokine mRNA response was assessed by use of a quantitative PCR assay. RESULTS Circulating blood neutrophils from horses with severe equine asthma had significantly lower bactericidal activity toward S zooepidemicus but not toward S equi, compared with results for control horses. Phagocytosis and mRNA expression of TNF-α, IL-8, and IL-10 were not different between groups. CONCLUSIONS AND CLINCAL RELEVANCE Impairment of bactericidal activity of circulating blood neutrophils in horses with severe equine asthma could contribute to an increased susceptibility to infections.
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An epizootic of Chlamydia psittaci equine reproductive loss associated with suspected spillover from native Australian parrots. Emerg Microbes Infect 2018; 7:88. [PMID: 29765033 PMCID: PMC5953950 DOI: 10.1038/s41426-018-0089-y] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 04/04/2018] [Accepted: 04/09/2018] [Indexed: 01/29/2023]
Abstract
Chlamydia psittaci is an avian pathogen capable of spill-over infections to humans. A parrot C. psittaci strain was recently detected in an equine reproductive loss case associated with a subsequent cluster of human C. psittaci infections. In this study, we screened for C. psittaci in cases of equine reproductive loss reported in regional New South Wales, Australia during the 2016 foaling season. C. psittaci specific-PCR screening of foetal and placental tissue samples from cases of equine abortion (n = 161) and foals with compromised health status (n = 38) revealed C. psittaci positivity of 21.1% and 23.7%, respectively. There was a statistically significant geographical clustering of cases ~170 km inland from the mid-coast of NSW (P < 0.001). Genomic analysis and molecular typing of C. psittaci positive samples from this study and the previous Australian equine index case revealed that the equine strains from different studs in regional NSW were clonal, while the phylogenetic analysis revealed that the C. psittaci strains from both Australian equine disease clusters belong to the parrot-associated 6BC clade, again indicative of spill-over of C. psittaci infections from native Australian parrots. The results of this work suggest that C. psittaci may be a more significant agent of equine reproductive loss than thought. A range of studies are now required to evaluate (a) the exact role that C. psittaci plays in equine reproductive loss; (b) the range of potential avian reservoirs and factors influencing infection spill-over; and (c) the risk that these equine infections pose to human health.
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Borel N, Polkinghorne A, Pospischil A. A Review on Chlamydial Diseases in Animals: Still a Challenge for Pathologists? Vet Pathol 2018; 55:374-390. [PMID: 29310550 DOI: 10.1177/0300985817751218] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Chlamydiae have a worldwide distribution causing a wide range of diseases in human hosts, livestock, and companion animals as well as in wildlife and exotic species. Moreover, they can persist in their hosts as asymptomatic infections for extended periods of time. The introduction of molecular techniques has revolutionized the Chlamydia field by expanding the host range of known chlamydial species but also by discovering new species and even new families of bacteria in the broader order Chlamydiales. The wide range of hosts, diseases, and tissues affected by chlamydiae complicate the diagnosis such that standard diagnostic approaches for these bacteria are rare. Bacteria of the Chlamydiales order are small and their inclusions are difficult to detect by standard microscopy. With the exception of avian and ovine chlamydiosis, macroscopic and/or histologic changes might not be pathognomic or indicative for a chlamydial infection or even not present at all. Moreover, detection of chlamydial DNA in specimens in the absence of other methods or related pathological lesions questions the significance of such findings. The pathogenic potential of the majority of recently identified Chlamydia-related bacteria remains largely unknown and awaits investigation through experimental or natural infection models including histomorphological characterization of associated lesions. This review aims to summarize the historical background and the most important developments in the field of animal chlamydial research in the past 5 years with a special focus on pathology. It will summarize the current nomenclature, present critical thoughts about diagnostics, and give an update on chlamydial infections in domesticated animals such as livestock, companion animals and birds, as well as free-ranging and captive wild animals such as reptiles, fish, and marsupials.
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Affiliation(s)
- Nicole Borel
- 1 Department of Pathobiology, Institute of Veterinary Pathology, University of Zurich, Zurich, Switzerland
| | - Adam Polkinghorne
- 2 Centre for Animal Health Innovation, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, Australia
| | - Andreas Pospischil
- 1 Department of Pathobiology, Institute of Veterinary Pathology, University of Zurich, Zurich, Switzerland
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Taylor KA, Durrheim D, Heller J, O'Rourke B, Hope K, Merritt T, Freeman P, Chicken C, Carrick J, Branley J, Massey P. Equine chlamydiosis-An emerging infectious disease requiring a one health surveillance approach. Zoonoses Public Health 2017; 65:218-221. [PMID: 28984040 DOI: 10.1111/zph.12391] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Indexed: 12/19/2022]
Abstract
Psittacosis is a rare but potentially fatal zoonosis caused by Chlamydia psittaci, an organism that is typically associated with bird contact. However C. psittaci is capable of infecting other non-avian hosts, such as horses, sheep, cattle and goats. Stud staff and veterinarians have significant exposure to parturient animals and reproductive materials in their routine work. To investigate the zoonotic potential associated with the emergence of C. psittaci as an abortifacient agent in horses, we established a programme of joint human and animal surveillance in a sentinel horse-breeding region in Australia. This programme comprised cross-notification of equine cases to public health agencies, and active follow-up of known human contacts, including stud workers, foaling staff, veterinarians and laboratory staff. We identified no confirmed cases of acute psittacosis despite intensive surveillance and testing of heavily exposed contacts; however, further work in the area is needed.
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Affiliation(s)
- K A Taylor
- Population Health Unit, Hunter New England Local Health, Wallsend, NSW, Australia
| | - D Durrheim
- Population Health Unit, Hunter New England Local Health, Wallsend, NSW, Australia.,School of Public Health and Medical Practice, University of Newcastle, Newcastle, NSW, Australia
| | - J Heller
- School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, NSW, Australia
| | - B O'Rourke
- Elizabeth Macarthur Agricultural Institute, New South Wales Department of Primary Industries, Menangle, NSW, Australia
| | - K Hope
- Health Protection, New South Wales Ministry of Health, North Sydney, NSW, Australia
| | - T Merritt
- Population Health Unit, Hunter New England Local Health, Wallsend, NSW, Australia
| | - P Freeman
- New South Wales Department of Primary Industries, Wollongbar, NSW, Australia
| | - C Chicken
- Scone Equine Hospital, Scone, NSW, Australia
| | - J Carrick
- Equine Specialist Consulting, Scone, NSW, Australia
| | - J Branley
- Westmead Clinical School, Nepean Hospital, Nepean, NSW, Australia
| | - P Massey
- Population Health Unit, Hunter New England Local Health, Wallsend, NSW, Australia
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16
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Prevalence of Chlamydia abortus Antibodies in Horses From the Northern State of Mexico and Its Relationship With Domestic Animals. J Equine Vet Sci 2017. [DOI: 10.1016/j.jevs.2017.05.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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17
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18
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Chan J, Doyle B, Branley J, Sheppeard V, Gabor M, Viney K, Quinn H, Janover O, McCready M, Heller J. An outbreak of psittacosis at a veterinary school demonstrating a novel source of infection. One Health 2017; 3:29-33. [PMID: 28616500 PMCID: PMC5454149 DOI: 10.1016/j.onehlt.2017.02.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 02/13/2017] [Accepted: 02/22/2017] [Indexed: 11/27/2022] Open
Abstract
In November 2014, New South Wales Health was notified of a cluster of respiratory illness in a veterinary school. Active case finding identified another case at a local equine stud. All cases had exposure to the equine fetal membranes of Mare A. This tissue subsequently tested positive for Chlamydia psittaci using quantitative real-time polymerase chain reaction. We conducted a cohort study of the university and stud farm staff to determine risk factors for disease. Nine people were exposed to the fetal membranes of Mare A. Of these, five cases of psittacosis were identified. Two required hospital admission. Contact with birds was not associated with illness (RR = 0.5, 95% CI = 0.09-2.73). People who had direct contact with the abnormal fetal membranes were more likely to develop disease (RR = 11.77, 95% CI = 1.02-∞). The emergence of an association between horse exposure and C. psittaci infection has important implications for the prevention and control of psittacosis. Article summary line: Investigation of an outbreak of psittacosis in a rural veterinary school demonstrates novel source of infection for psittacosis through exposure to abnormal equine fetal membranes.
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Affiliation(s)
- Jocelyn Chan
- Health Protection New South Wales (NSW), NSW Health, North Sydney, NSW, Australia.,National Centre for Epidemiology and Population Health (NCEPH), Australian National University, Canberra, Australian Capital Territory (ACT), Australia
| | - Bridget Doyle
- Public Health Unit, Murrumbidgee Local Health District, Albury, NSW, Australia
| | | | - Vicky Sheppeard
- Health Protection New South Wales (NSW), NSW Health, North Sydney, NSW, Australia
| | - Melinda Gabor
- State Veterinary Diagnostic Laboratory, Department of Primary Industry, Menangle, NSW, Australia
| | - Kerri Viney
- National Centre for Epidemiology and Population Health (NCEPH), Australian National University, Canberra, Australian Capital Territory (ACT), Australia
| | - Helen Quinn
- National Centre for Immunisation Research and Surveillance of Vaccine Preventable Diseases (NCIRS), The Children's Hospital at Westmead, Sydney, NSW, Australia.,Discipline of Paediatrics and Child Health, University of Sydney, The Children's Hospital at Westmead, Sydney, NSW, Australia
| | - Orly Janover
- Public Health Unit, Murrumbidgee Local Health District, Albury, NSW, Australia
| | | | - Jane Heller
- School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, NSW, Australia
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Radomski N, Einenkel R, Müller A, Knittler MR. Chlamydia-host cell interaction not only from a bird's eye view: some lessons fromChlamydia psittaci. FEBS Lett 2016; 590:3920-3940. [DOI: 10.1002/1873-3468.12295] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Revised: 07/06/2016] [Accepted: 07/07/2016] [Indexed: 12/13/2022]
Affiliation(s)
- Nadine Radomski
- Friedrich-Loeffler-Institut; Institute of Immunology; Isle of Riems Germany
| | - Rebekka Einenkel
- Friedrich-Loeffler-Institut; Institute of Immunology; Isle of Riems Germany
| | - Anne Müller
- Friedrich-Loeffler-Institut; Institute of Immunology; Isle of Riems Germany
| | - Michael R Knittler
- Friedrich-Loeffler-Institut; Institute of Immunology; Isle of Riems Germany
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20
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Diel de Amorim M, Nielsen K, McKell B, Huang Y, Card C. Aortic rupture causing cardiac tamponade in a 24-day-old Friesian colt with concurrent colonic Chlamydiosisand Balantidiasis. EQUINE VET EDUC 2016. [DOI: 10.1111/eve.12402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- M. Diel de Amorim
- Department of Large Animal Clinical Sciences; Western College of Veterinary Medicine; University of Saskatchewan; Saskatoon Canada
| | - K. Nielsen
- Department of Large Animal Clinical Sciences; Western College of Veterinary Medicine; University of Saskatchewan; Saskatoon Canada
| | - B. McKell
- Department of Large Animal Clinical Sciences; Western College of Veterinary Medicine; University of Saskatchewan; Saskatoon Canada
| | - Y. Huang
- Prairie Diagnostic Services Inc.; Saskatoon Canada
| | - C. Card
- Department of Large Animal Clinical Sciences; Western College of Veterinary Medicine; University of Saskatchewan; Saskatoon Canada
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21
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Cian F, Monti P, Durham A. Cytology of the lower respiratory tract in horses: An updated review. EQUINE VET EDUC 2015. [DOI: 10.1111/eve.12376] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- F. Cian
- Animal Health Trust; Newmarket Suffolk UK
| | - P. Monti
- Dick White Referrals; Six Mile Bottom Suffolk UK
| | - A. Durham
- Liphook Equine Hospital; Liphook Hampshire UK
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Enrofloxacin and macrolides alone or in combination with rifampicin as antimicrobial treatment in a bovine model of acute Chlamydia psittaci infection. PLoS One 2015; 10:e0119736. [PMID: 25768665 PMCID: PMC4358964 DOI: 10.1371/journal.pone.0119736] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 01/15/2015] [Indexed: 12/26/2022] Open
Abstract
Chlamydia psittaci is a zoonotic bacterium with a wide host range that can cause respiratory disease in humans and cattle. In the present study, effects of treatment with macrolides and quinolones applied alone or in combination with rifampicin were tested in a previously established bovine model of respiratory C. psittaci infection. Fifty animals were inoculated intrabronchially at the age of 6-8 weeks. Seven served as untreated controls, the others were assigned to seven treatment groups: (i) rifampicin, (ii) enrofloxacin, (iii) enrofloxacin + rifampicin, (iv) azithromycin, (v) azithromycin + rifampicin, (vi) erythromycin, and (vii) erythromycin + rifampicin. Treatment started 30 hours after inoculation and continued until 14 days after inoculation (dpi), when all animals were necropsied. The infection was successful in all animals and sufficient antibiotic levels were detected in blood plasma and tissue of the treated animals. Reisolation of the pathogen was achieved more often from untreated animals than from other groups. Nevertheless, pathogen detection by PCR was possible to the same extent in all animals and there were no significant differences between treated and untreated animals in terms of local (i.e., cell count and differentiation of BALF-cells) and systemic inflammation (i.e. white blood cells and concentration of acute phase protein LBP), clinical signs, and pathological findings at necropsy. Regardless of the reduced reisolation rate in treated animals, the treatment of experimentally induced respiratory C. psittaci infection with enrofloxacin, azithromycin or erythromycin alone or in combination with rifampicin was without obvious benefit for the host, since no significant differences in clinical and pathological findings or inflammatory parameters were detected and all animals recovered clinically within two weeks.
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Hansen S, Baptiste K, Fjeldborg J, Horohov D. A review of the equine age-related changes in the immune system: comparisons between human and equine aging, with focus on lung-specific immune-aging. Ageing Res Rev 2015; 20:11-23. [PMID: 25497559 DOI: 10.1016/j.arr.2014.12.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2014] [Revised: 10/04/2014] [Accepted: 12/02/2014] [Indexed: 11/27/2022]
Abstract
The equine aging process involves many changes to the immune system that may be related to genetics, the level of nutrition, the environment and/or an underlying subclinical disease. Geriatric horses defined as horses above the age of 20, exhibit a decline in body condition, muscle tone and general well-being. It is not known whether these changes contribute to decreased immune function or are the result of declining immune function. Geriatric years are characterized by increased susceptibility to infections and a reduced antibody response to vaccination as a result of changes in the immune system. Humans and horses share many of these age-related changes, with only a few differences. Thus, inflamm-aging and immunosenescence are well-described phenomena in both human and equine research, particularly in relation to the peripheral blood and especially the T-cell compartment. However, the lung is faced with unique challenges because of its constant interaction with the external environment and thus may not share similarities to peripheral blood when considering age-related changes in immune function. Indeed, recent studies have shown discrepancies in cytokine mRNA and protein expression between the peripheral blood and bronchoalveolar lavage immune cells. These results provide important evidence that age-related immune changes or 'dys-functions' are organ-specific.
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24
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Knittler MR, Sachse K. Chlamydia psittaci: update on an underestimated zoonotic agent. Pathog Dis 2014; 73:1-15. [PMID: 25853998 DOI: 10.1093/femspd/ftu007] [Citation(s) in RCA: 139] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/24/2014] [Indexed: 12/16/2022] Open
Abstract
Chlamydia (C.) psittaci is an economically relevant pathogen in poultry and pet birds, where it causes psittacosis/ornithosis, and also a human pathogen causing atypical pneumonia after zoonotic transmission. Despite its well-documented prevalence, the agent has received less attention by researchers than other Chlamydia spp. in the last decades. In the present paper, we review recently published data on C. psittaci infection and attempt to single out characteristic features distinguishing it from related chlamydial agents. It is remarkable that C. psittaci is particularly efficient in disseminating in the host organism causing systemic disease, which occasionally can take a fulminant course. At the cellular level, the pathogen's broad host cell spectrum (from epithelial cells to macrophages), its rapid entry and fast replication, proficient use of intracellular transport routes to mitochondria and the Golgi apparatus, the pronounced physical association of chlamydial inclusions with energy-providing cell compartments, as well as the subversive regulation of host cell survival during productive and persistent states facilitate the characteristic efficient growth and successful host-to-host spread of C. psittaci. At the molecular level, the pathogen was shown to upregulate essential chlamydial genes when facing the host immune response. We hypothesize that this capacity, in concert with expression of specific effectors of the type III secretion system and efficient suppression of selected host defense signals, contributes to successful establishment of the infection in the host. Concerning the immunology of host-pathogen interactions, C. psittaci has been shown to distinguish itself by coping more efficiently than other chlamydiae with pro-inflammatory mediators during early host response, which can, to some extent, explain the effective evasion and adaptation strategies of this bacterium. We conclude that thorough analysis of the large number of whole-genome sequences already available will be essential to identify genetic markers of the species-specific features and trigger more in-depth studies in cellular and animal models to address such vital topics as treatment and vaccination.
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Affiliation(s)
- Michael R Knittler
- Institute of Immunology, Friedrich-Loeffler-Institut, Isle of Riems, 07743 Jena, Germany
| | - Konrad Sachse
- Institute of Molecular Pathogenesis, Friedrich-Loeffler-Institut, 07743 Jena, Germany
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Knittler MR, Berndt A, Böcker S, Dutow P, Hänel F, Heuer D, Kägebein D, Klos A, Koch S, Liebler-Tenorio E, Ostermann C, Reinhold P, Saluz HP, Schöfl G, Sehnert P, Sachse K. Chlamydia psittaci: New insights into genomic diversity, clinical pathology, host–pathogen interaction and anti-bacterial immunity. Int J Med Microbiol 2014; 304:877-93. [DOI: 10.1016/j.ijmm.2014.06.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
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26
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Evaluation of Right Ventricular Myocardial Function in Healthy Horses With Recurrent Airway Obstruction Using Tissue Doppler Imaging. J Equine Vet Sci 2014. [DOI: 10.1016/j.jevs.2014.06.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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27
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Evolution to a chronic disease niche correlates with increased sensitivity to tryptophan availability for the obligate intracellular bacterium Chlamydia pneumoniae. J Bacteriol 2014; 196:1915-24. [PMID: 24682324 DOI: 10.1128/jb.01476-14] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The chlamydiae are obligate intracellular parasites that have evolved specific interactions with their various hosts and host cell types to ensure their successful survival and consequential pathogenesis. The species Chlamydia pneumoniae is ubiquitous, with serological studies showing that most humans are infected at some stage in their lifetime. While most human infections are asymptomatic, C. pneumoniae can cause more-severe respiratory disease and pneumonia and has been linked to chronic diseases such as asthma, atherosclerosis, and even Alzheimer's disease. The widely dispersed animal-adapted C. pneumoniae strains cause an equally wide range of diseases in their hosts. It is emerging that the ability of C. pneumoniae to survive inside its target cells, including evasion of the host's immune attack mechanisms, is linked to the acquisition of key metabolites. Tryptophan and arginine are key checkpoint compounds in this host-parasite battle. Interestingly, the animal strains of C. pneumoniae have a slightly larger genome, enabling them to cope better with metabolite restrictions. It therefore appears that as the evolutionarily more ancient animal strains have evolved to infect humans, they have selectively become more "susceptible" to the levels of key metabolites, such as tryptophan. While this might initially appear to be a weakness, it allows these human C. pneumoniae strains to exquisitely sense host immune attack and respond by rapidly reverting to a persistent phase. During persistence, they reduce their metabolic levels, halting progression of their developmental cycle, waiting until the hostile external conditions have passed before they reemerge.
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Ostermann C, Linde S, Siegling-Vlitakis C, Reinhold P. Evaluation of pulmonary dysfunctions and acid-base imbalances induced by Chlamydia psittaci in a bovine model of respiratory infection. Multidiscip Respir Med 2014; 9:10. [PMID: 24517577 PMCID: PMC4021058 DOI: 10.1186/2049-6958-9-10] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 12/18/2013] [Indexed: 01/19/2023] Open
Abstract
Background Chlamydia psittaci (Cp) is a respiratory pathogen capable of inducing acute pulmonary zoonotic disease (psittacosis) or persistent infection. To elucidate the pathogenesis of this infection, a translational large animal model was recently introduced by our group. This study aims at quantifying and differentiating pulmonary dysfunction and acid–base imbalances induced by Cp. Methods Forty-two calves were grouped in (i) animals inoculated with Cp (n = 21) and (ii) controls sham-inoculated with uninfected cell culture (n = 21). For pulmonary function testing, impulse oscillometry, capnography, and FRC (functional residual capacity) measurement were applied to spontaneously breathing animals. Variables of acid–base status were assessed in venous blood using both (i) traditional Henderson-Hasselbalch and (ii) strong ion approach. Results Both obstructive and restrictive pulmonary disorders were induced in calves experimentally inoculated with Cp. Although disorders in respiratory mechanics lasted for 8–11 days, the pattern of spontaneous breathing was mainly altered in the period of acute illness (until 4 days post inoculation, dpi). Expiration was more impaired than inspiration, resulting in elevated FRC. Ventilation was characterised by a reduction in tidal volume (−25%) combined with an increased percentage of dead space volume and a significant reduction of alveolar volume by 10%. Minute ventilation increased significantly (+50%) due to a compensatory doubling of respiratory rate. Hyperventilatory hypocapnia at 2–3 dpi resulted in slightly increased blood pH at 2 dpi. However, the acid–base equilibrium was additionally influenced by metabolic components, i.e. the systemic inflammatory response, all of which were detected with help of the strong ion theory. Decreased concentrations of albumin (2–10 dpi), a negative acute-phase marker, resulted in a decrease in the sum of non-volatile weak acids (Atot), revealing an alkalotic effect. This was counterbalanced by acidic effects of decreased strong ion difference (SID), mediated by the interplay between hypochloraemia (alkalotic effect) and hyponatraemia (acidic effect). Conclusions This bovine model was found to be suitable for studying pathophysiology of respiratory Cp infection and may help elucidating functional host-pathogen interactions in the mammalian lung.
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Affiliation(s)
- Carola Ostermann
- Institute of Molecular Pathogenesis at 'Friedrich-Loeffler-Institut' (Federal Research Institute for Animal Health), Naumburger Str. 96a, 07743 Jena, Germany
| | - Susanna Linde
- Institute of Molecular Pathogenesis at 'Friedrich-Loeffler-Institut' (Federal Research Institute for Animal Health), Naumburger Str. 96a, 07743 Jena, Germany
| | | | - Petra Reinhold
- Institute of Molecular Pathogenesis at 'Friedrich-Loeffler-Institut' (Federal Research Institute for Animal Health), Naumburger Str. 96a, 07743 Jena, Germany
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29
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Jiménez D, Romero-Zuñiga J, Dolz G. Serosurveillance of infectious agents in equines of the Central Valley of Costa Rica. Open Vet J 2014; 4:107-12. [PMID: 26623349 PMCID: PMC4629603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 10/29/2014] [Indexed: 10/26/2022] Open
Abstract
Blood samples from 181 equines from the Central Valley of Costa Rica were collected in the year 2012 to determine the presence of antibodies against selected infectious agents in horses and to determine the risk factors associated with these agents. The presence of antibodies against Equine Infectious Anemia Virus (EIAV), Equine Herpes Virus 1 and 4 (EHV-1 and EHV-4), West Nile Virus (WNV), Influenza A Virus (IAV), Equine Viral Arteritis Virus (EVAV), Babesia caballi, Theileria equi, Neospora caninum and Chlamydia abortus was determined using commercial assays, and risk factors associated with seropositivity to the different infectious agents was established. The most seroprevalent agent detected was EHV-4 (96.7%), followed by WNV (44.2%), and IAV (41.8%). Horses >3 years, used for work or sports, and with access to pastures, had significantly increased probability to be seropositive to WNV, whereas horses used for breeding and recreational purposes, being stabled, and without access to pastures, had significantly greater probability to be seropositive to IAV. Seroprevalence to B. caballi (19.9%) was lower than to T. equi (38.1%). For B. caballi, access to pastures was determined as a risk factor, whereas being older than 3 years was established as a risk factor for T. equi. Low seroprevalences were determined for EHV-1 (5.0%), EVAV (5.0%), C. abortus (4.8%), and N. caninum (4.4%). Mares having history of abortion were more likely to be seropositive to EHV-1, whereas horses >3 years, used for work and sports, and mares having multiple parturitions, were more likely to be seropositive to N. caninum. None of the horses were seropositive to EIAV. Earlier, only diseases caused by EIAV, WNV and piroplasmosis were reported in Costa Rica. The present study however, determined the presence of carriers for EHV-1, EHV-4, and EIAV.
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Affiliation(s)
- D. Jiménez
- Programa de Investigación en Medicina Poblacional, Escuela de Medicina Veterinaria, Universidad Nacional, P.O. Box 86-3000, Heredia, Costa Rica
| | - J.J. Romero-Zuñiga
- Programa de Investigación en Medicina Poblacional, Escuela de Medicina Veterinaria, Universidad Nacional, P.O. Box 86-3000, Heredia, Costa Rica
| | - G. Dolz
- Programa de Investigación en Medicina Poblacional, Escuela de Medicina Veterinaria, Universidad Nacional, P.O. Box 86-3000, Heredia, Costa Rica,Corresponding Author: Gaby Dolz. Escuela de Medicina Veterinaria, Universidad Nacional, P.O. Box 86-3000, Heredia, Costa Rica. Tel.: (506) 2562 4553, Fax: (506) 2237 5229.
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Dutow P, Fehlhaber B, Bode J, Laudeley R, Rheinheimer C, Glage S, Wetsel RA, Pabst O, Klos A. The complement C3a receptor is critical in defense against Chlamydia psittaci in mouse lung infection and required for antibody and optimal T cell response. J Infect Dis 2013; 209:1269-78. [PMID: 24273177 DOI: 10.1093/infdis/jit640] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND The complement system protects against extracellular pathogens and links innate and adaptive immunity. In this study, we investigated the anaphylatoxin C3a receptor (C3aR) in Chlamydia psittaci lung infection and elucidated C3a-dependent adaptive immune mechanisms. METHODS Survival, body weight, and clinical score were monitored in primary mouse infection and after serum transfer. Bacterial load, histology, cellular distribution, cytokines, antibodies, and lymphocytes were analyzed. RESULTS C3aR(-/-) mice showed prolonged pneumonia with decreased survival, lower weight, and higher clinical score. Compared to wild-type mice bacterial clearance was impaired, and inflammatory parameters were increased. In lung-draining lymph nodes of C3aR(-/-) mice the total number of B cells, CD4(+) T cells, and Chlamydia-specific IFN-γ(+) (CD4(+) or CD8(+)) cells was reduced upon infection, and the mice were incapable of Chlamydia-specific immunoglobulin M or immunoglobulin G production. Performed before infection, transfer of hyperimmune serum prolonged survival of C3aR(-/-) mice. CONCLUSIONS C3a and its receptor are critical for defense against C. psittaci in mouse lung infection. In this model, C3a acts via its receptor as immune modulator. Enhancement of specific B and T cell responses upon infection with an intracellular bacterium were identified as hitherto unknown features of C3a/C3aR. These new functions might be of general immunological importance.
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Affiliation(s)
- Pavel Dutow
- Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School (MHH)
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Ostermann C, Rüttger A, Schubert E, Schrödl W, Sachse K, Reinhold P. Infection, disease, and transmission dynamics in calves after experimental and natural challenge with a Bovine Chlamydia psittaci isolate. PLoS One 2013; 8:e64066. [PMID: 23691148 PMCID: PMC3653844 DOI: 10.1371/journal.pone.0064066] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Accepted: 04/11/2013] [Indexed: 11/19/2022] Open
Abstract
Chlamydia (C.) psittaci is the causative agent of psittacosis, a zoonotic disease in birds and man. In addition, C. psittaci has been repeatedly found in domestic animals and is, at least in calves, also able to induce respiratory disease. Knowledge about transmission routes in cattle herds is still deficient, and nothing is known about differences in host response after either experimental or natural exposure to C. psittaci. Therefore, our recently developed respiratory infection model was exploited to evaluate (i) the presence of the pathogen in blood, excretions and air, (ii) the possibility of transmission and (iii) clinical symptoms, acute phase and immune response until 5 weeks after exposure. In this prospective study, intrabronchial inoculation of 108 inclusion-forming units of C. psittaci (n = 21 calves) led to reproducible acute respiratory illness (of approximately one week), accompanied by a systemic inflammatory reaction with an innate immune response dominated by neutrophils. Excretion and/or exhalation of the pathogen was sufficient to transmit the infection to naïve sentinel calves (n = 3) co-housed with the infected animals. Sentinel calves developed mild to subclinical infections only. Notably, excretion of the pathogen, predominantly via feces, occurred more frequently in animals naturally exposed to C. psittaci (i.e. sentinels) as compared to experimentally-inoculated calves. The humoral immune response was generally weak, and did not emerge regularly following experimental infection; however, it was largely absent after naturally acquired infection.
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Affiliation(s)
- Carola Ostermann
- Institute of Molecular Pathogenesis at 'Friedrich-Loeffler-Institut' (Federal Research Institute for Animal Health), Jena, Germany.
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Comparative analysis of Chlamydia psittaci genomes reveals the recent emergence of a pathogenic lineage with a broad host range. mBio 2013; 4:mBio.00604-12. [PMID: 23532978 PMCID: PMC3622922 DOI: 10.1128/mbio.00604-12] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Chlamydia psittaci is an obligate intracellular bacterium. Interest in Chlamydia stems from its high degree of virulence as an intestinal and pulmonary pathogen across a broad range of animals, including humans. C. psittaci human pulmonary infections, referred to as psittacosis, can be life-threatening, which is why the organism was developed as a bioweapon in the 20th century and is listed as a CDC biothreat agent. One remarkable recent result from comparative genomics is the finding of frequent homologous recombination across the genome of the sexually transmitted and trachoma pathogen Chlamydia trachomatis. We sought to determine if similar evolutionary dynamics occurred in C. psittaci. We analyzed 20 C. psittaci genomes from diverse strains representing the nine known serotypes of the organism as well as infections in a range of birds and mammals, including humans. Genome annotation revealed a core genome in all strains of 911 genes. Our analyses showed that C. psittaci has a history of frequently switching hosts and undergoing recombination more often than C. trachomatis. Evolutionary history reconstructions showed genome-wide homologous recombination and evidence of whole-plasmid exchange. Tracking the origins of recombinant segments revealed that some strains have imported DNA from as-yet-unsampled or -unsequenced C. psittaci lineages or other Chlamydiaceae species. Three ancestral populations of C. psittaci were predicted, explaining the current population structure. Molecular clock analysis found that certain strains are part of a clonal epidemic expansion likely introduced into North America by South American bird traders, suggesting that psittacosis is a recently emerged disease originating in New World parrots. Chlamydia psittaci is classified as a CDC biothreat agent based on its association with life-threatening lung disease, termed psittacosis, in humans. Because of the recent remarkable findings of frequent recombination across the genome of the human sexually transmitted and ocular trachoma pathogen Chlamydia trachomatis, we sought to determine if similar evolutionary dynamics occur in C. psittaci. Twenty C. psittaci genomes were analyzed from diverse strains that may play a pathogenic role in human disease. Evolution of the strains revealed genome-wide recombination occurring at a higher rate than for C. trachomatis. Certain strains were discovered to be part of a recent epidemic clonal expansion originating in South America. These strains may have been introduced into the United States from South American bird traders, suggesting that psittacosis is a recently emerged disease originating in New World parrots. Our analyses indicate that C. psittaci strains have a history of frequently switching hosts and undergoing recombination.
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Fiegl D, Kägebein D, Liebler-Tenorio EM, Weisser T, Sens M, Gutjahr M, Knittler MR. Amphisomal route of MHC class I cross-presentation in bacteria-infected dendritic cells. THE JOURNAL OF IMMUNOLOGY 2013; 190:2791-806. [PMID: 23418629 DOI: 10.4049/jimmunol.1202741] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Dendritic cells (DCs) are among the first professional APCs encountered by the obligate intracellular bacterium Chlamydia during infection. Using an established mouse bone marrow-derived DC line, we show that DCs control chlamydial infection in multiple small inclusions characterized by restricted bacterial growth, impaired cytosolic export of the virulence factor chlamydial protease-like activity factor, and interaction with guanylate-binding protein 1, a host cell factor involved in the initiation of autophagy. During maturation of infected DCs, chlamydial inclusions disintegrate, likely because they lack chlamydial protease-like activity factor-mediated protection. Released cytosolic Chlamydia are taken up by autophagosomes and colocalize with cathepsin-positive amphisomal vacuoles, to which peptide transporter TAP and upregulated MHC class I (MHC I) are recruited. Chlamydial Ags are subsequently generated through routes involving preprocessing in amphisomes via cathepsins and entry into the cytosol for further processing by the proteasome. Finally, bacterial peptides are reimported into the endosomal pathway for loading onto recycling MHC I. Thus, we unravel a novel pathway of MHC I-mediated cross-presentation that is initiated with a host cellular attack physically disrupting the parasitophorous vacuole, involves autophagy to collect cytosolic organisms into autophagosomes, and concludes with complex multistep antigenic processing in separate cellular compartments.
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Affiliation(s)
- Dorothee Fiegl
- Institute of Immunology, Federal Research Institute for Animal Health, Friedrich-Loeffler-Institute, 17493 Greifswald-Isle of Riems, Germany
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Reinhold P, Ostermann C, Liebler-Tenorio E, Berndt A, Vogel A, Lambertz J, Rothe M, Rüttger A, Schubert E, Sachse K. A bovine model of respiratory Chlamydia psittaci infection: challenge dose titration. PLoS One 2012; 7:e30125. [PMID: 22299031 PMCID: PMC3267716 DOI: 10.1371/journal.pone.0030125] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2011] [Accepted: 12/09/2011] [Indexed: 12/26/2022] Open
Abstract
This study aimed to establish and evaluate a bovine respiratory model of experimentally induced acute C. psittaci infection. Calves are natural hosts and pathogenesis may resemble the situation in humans. Intrabronchial inoculation of C. psittaci strain DC15 was performed in calves aged 2–3 months via bronchoscope at four different challenge doses from 106 to 109 inclusion-forming units (ifu) per animal. Control groups received either UV-inactivated C. psittaci or cell culture medium. While 106 ifu/calf resulted in a mild respiratory infection only, the doses of 107 and 108 induced fever, tachypnea, dry cough, and tachycardia that became apparent 2–3 days post inoculation (dpi) and lasted for about one week. In calves exposed to 109 ifu C. psittaci, the respiratory disease was accompanied by severe systemic illness (apathy, tremor, markedly reduced appetite). At the time point of most pronounced clinical signs (3 dpi) the extent of lung lesions was below 10% of pulmonary tissue in calves inoculated with 106 and 107 ifu, about 15% in calves inoculated with 108 and more than 30% in calves inoculated with 109 ifu C. psittaci. Beside clinical signs and pathologic lesions, the bacterial load of lung tissue and markers of pulmonary inflammation (i.e., cell counts, concentration of proteins and eicosanoids in broncho-alveolar lavage fluid) were positively associated with ifu of viable C. psittaci. While any effect of endotoxin has been ruled out, all effects could be attributed to infection by the replicating bacteria. In conclusion, the calf represents a suitable model of respiratory chlamydial infection. Dose titration revealed that both clinically latent and clinically manifest infection can be reproduced experimentally by either 106 or 108 ifu/calf of C. psittaci DC15 while doses above 108 ifu C. psittaci cannot be recommended for further studies for ethical reasons. This defined model of different clinical expressions of chlamydial infection allows studying host-pathogen interactions.
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Affiliation(s)
- Petra Reinhold
- Institute of Molecular Pathogenesis at 'Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Jena, Germany.
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Chen D, Lei L, Flores R, Huang Z, Wu Z, Chai J, Zhong G. Autoprocessing and self-activation of the secreted protease CPAF in Chlamydia-infected cells. Microb Pathog 2010; 49:164-73. [PMID: 20510344 DOI: 10.1016/j.micpath.2010.05.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2009] [Revised: 05/14/2010] [Accepted: 05/18/2010] [Indexed: 10/19/2022]
Abstract
The Chlamydia-secreted protease/proteasome-like activity factor (CPAF) is synthesized as a proenzyme (proCPAF) and requires processing for proteolytic activity. Recent structural studies have further demonstrated that CPAF is a serine protease that can undergo autoprocessing and self-activation in a concentration-dependent manner in vitro. However, it is not known how CPAF is processed and activated during chlamydial infection. In the current study, we used a mutant CPAF designated as CPAF(E558A) that is deficient in processing by itself as a substrate to search for putative CPAF activation factor(s) in Chlamydia-infected cells. CPAF(E558A) was processed by the lysates made from Chlamydia-infected cells and the processing activity correlated with the presence of endogenous active CPAF in the fractionated lysate samples. CPAF produced in the Chlamydia-infected cells is required for processing the mutant CPAF(E558A) since the processing activity was removed by depletion with anti-CPAF but not control antibodies. Furthermore, a purified and activated wild type CPAF alone was sufficient for processing CPAF(E558A) and no other chlamydial proteases are required. Finally, fusion tag-induced oligomerization can lead to autoprocessing and self-activation of the wild type CPAF in mammalian cells. These observations together have demonstrated that CPAF undergoes autoprocessing and self-activation during chlamydial infection.
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Affiliation(s)
- Ding Chen
- Department of Microbiology and Immunology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
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Abstract
A secreted chlamydial protease designated CPAF (Chlamydial Protease/proteasome-like Activity Factor) degrades host proteins, enabling Chlamydia to evade host defenses and replicate. The mechanistic details of CPAF action, however, remain obscure. We used a computational approach to search the protein databank for structures that are compatible with the CPAF amino acid sequence. The results reveal that CPAF possesses a fold similar to that of the catalytic domains of the tricorn protease from Thermoplasma acidophilum,and that CPAF residues H105, S499, and E558 are structurally analogous to the tricorn protease catalytic triad residues H746, S965, and D1023. Substitution of these putative CPAF catalytic residues blocked CPAF from degrading substrates in vitro, while the wild type and a noncatalytic control mutant of CPAF remained cleavage-competent. Substrate cleavage is also correlated with processing of CPAF into N-terminal (CPAFn) and C-terminal (CPAFc) fragments, suggesting that these putative catalytic residues may also be required for CPAF maturation.
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Zoonotic potential of Chlamydophila. Vet Microbiol 2009; 140:382-91. [PMID: 19345022 DOI: 10.1016/j.vetmic.2009.03.014] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2009] [Revised: 02/23/2009] [Accepted: 03/02/2009] [Indexed: 11/24/2022]
Abstract
The purpose of this article is to present the diseases induced in humans and animals by the different species of Chlamydophila, after providing an overview on the history of these infectious agents and their taxonomy. The route of transmission and the available methods for prevention and control in the different animal species are reviewed.
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