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Häcker G. Chlamydia in pigs: intriguing bacteria associated with sub-clinical carriage and clinical disease, and with zoonotic potential. Front Cell Dev Biol 2024; 12:1301892. [PMID: 39206090 PMCID: PMC11349706 DOI: 10.3389/fcell.2024.1301892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 06/17/2024] [Indexed: 09/04/2024] Open
Abstract
Chlamydiae are bacteria that are intriguing and important at the same time. The genus Chlamydia encompasses many species of obligate intracellular organisms: they can multiply only inside the cells of their host organism. Many, perhaps most animals have their own specifically adapted chlamydial species. In humans, the clinically most relevant species is Chlamydia trachomatis, which has particular importance as an agent of sexually transmitted disease. Pigs are the natural host of Chlamydia suis but may also carry Chlamydia abortus and Chlamydia pecorum. C. abortus and possibly C. suis have anthropozoonotic potential, which makes them interesting to human medicine, but all three species bring a substantial burden of disease to pigs. The recent availability of genomic sequence comparisons suggests adaptation of chlamydial species to their respective hosts. In cell biological terms, many aspects of all the species seem similar but non-identical: the bacteria mostly replicate within epithelial cells; they are taken up by the host cell in an endosome that they customize to generate a cytosolic vacuole; they have to evade cellular defences and have to organize nutrient transport to the vacuole; finally, they have to organize their release to be able to infect the next cell or the next host. What appears to be very difficult and challenging to achieve, is in fact a greatly successful style of parasitism. I will here attempt to cover some of the aspects of the infection biology of Chlamydia, from cell biology to immune defence, epidemiology and possibilities of prevention. I will discuss the pig as a host species and the species known to infect pigs but will in particular draw on the more detailed knowledge that we have on species that infect especially humans.
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Affiliation(s)
- Georg Häcker
- Institute of Medical Microbiology and Hygiene, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany
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Richardson S, Bell CR, Medhavi F, Tanner T, Lundy S, Omosun Y, Igietseme JU, Eko FO. A novel cold-chain free VCG-based subunit vaccine protects against Chlamydia abortus-induced neonatal mortality in a pregnant mouse model. Front Immunol 2023; 14:1243743. [PMID: 37915580 PMCID: PMC10616880 DOI: 10.3389/fimmu.2023.1243743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 09/28/2023] [Indexed: 11/03/2023] Open
Abstract
Chlamydia abortus (Cab) causes spontaneous abortion and neonatal mortality in infected ruminants and pregnant women. Most Cab infections are asymptomatic, although they can be treated with antibiotics, signifying that control of these infections may require alternative strategies, including the use of effective vaccines. However, the limitations imposed by live attenuated and inactivated vaccines further suggest that employment of subunit vaccines may need to be considered. The efficacy of a newly generated Vibrio cholerae ghost (rVCG)-based subunit vaccine harboring the N-terminal portion of the Cab Pmp18D protein (rVCG-Pmp18.3) in preventing Cab-induced abortion or neonatal mortality was evaluated in pregnant mice. Mice were intranasally (IN) immunized and boosted twice, 2 weeks apart with the vaccine, and immunized and unimmunized mice were caged with males 4 weeks postimmunization. The mice were then infected either IN or transcervically (TC) 10 days after pregnancy, and the fertility rate was determined 7 days postpartum. Eight days after delivery, the mice were sacrificed, and Cab infectivity in the lungs and spleens was evaluated by culturing tissue homogenates in tissue culture. Our results demonstrated that the vaccine induced immune effectors that mediated complete clearance of infection in the lungs and significantly reduced Cab infectivity in the spleen following IN immunization. Vaccine immunization also afforded protection against Cab-induced upper genital tract pathology (uterine dilation). Furthermore, while there was no incidence of abortion in both immunized and unimmunized mice, immunized mice were completely protected against neonatal mortality compared to unimmunized infected controls, which lost a significant percentage of their litter 7 days postpartum. Our results establish the capability of the rVCG-Pmp18.3 vaccine to prevent infection in the lungs (mucosal) and spleen (systemic) and protect mice from Cab-induced tubal pathologies and neonatal mortality, a hallmark of Cab infection in ruminants. To advance the commercial potential of this vaccine, future studies will optimize the antigen dose and the number of vaccine doses required for protection of ruminants.
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Affiliation(s)
- Shakyra Richardson
- Department of Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, Atlanta, GA, United States
| | - Courtnee R. Bell
- Department of Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, Atlanta, GA, United States
| | - Fnu Medhavi
- Department of Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, Atlanta, GA, United States
| | - Tayhlor Tanner
- Department of Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, Atlanta, GA, United States
| | - Stephanie Lundy
- Department of Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, Atlanta, GA, United States
| | - Yusuf Omosun
- Department of Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, Atlanta, GA, United States
| | - Joseph U. Igietseme
- National Center for Emerging Zoonotic and Infectious Diseases, Center for Disease Control and Prevention (CDC), Atlanta, GA, United States
| | - Francis O. Eko
- Department of Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, Atlanta, GA, United States
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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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Marzok M, Hereba AM, Kandeel M, Selim A. Serosurvey and associated risk factors for Chlamydia abortus infection in cattle from Egypt. Comp Immunol Microbiol Infect Dis 2023; 96:101972. [PMID: 36989678 DOI: 10.1016/j.cimid.2023.101972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 03/06/2023] [Accepted: 03/21/2023] [Indexed: 03/29/2023]
Abstract
Chlamydia abortus is an important gram-negative pathogen poses serious public health problem in human and reproductive disorders in animals. There are very few data on the prevalence of C. abortus in cattle and none on the associated risk factors for infection in cattle in earlier literature. Therefore, the objective of the current study was to evaluate the risk factors and seropositivity of C. abortus infection in cattle. In northern Egypt, 400 cattle from five governorates were examined using indirect enzyme-linked immunosorbent assay (ELISA) in a cross-sectional study. The results revealed that the overall prevalence for C. abortus in cattle was 20.75 % and the highest level was observed in Gharbia 26.67 % while the lowest rate was found in Menofia governorate 15.38 %. The age, herd size, application of disinfection and history of abortion or stillbirth had significant association with prevalence of C. abortus infection by univariate analysis. In addition, Cattle above the age of 4 years, a median herd size of 10-50, the absence of disinfectant application, a history of stillbirth, and a history of abortion were all found as risk factors for C. abortus infection using multivariable logistic regression. These findings could be used to establish effective management strategies to prevent and control C. abortus infection in cattle and lower the risk of C. abortus infection in cattle in Egypt.
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Martínez-Serrano MG, Díaz-Aparicio E, Palomares-Reséndiz G, Tórtora-Pérez JL, Ramírez-Álvarez H, Ortega-Hernández N, Salinas-Lorente J, Morales-Alvarez JF, Cervantes-Morali JJC. Presence of Chlamydia abortus in colostrum, milk and vaginal discharge samples of sheep. REV COLOMB CIENC PEC 2022. [DOI: https:/doi.org/10.17533/udea.rccp.v35n2a04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Background: The main transmission route of Chlamydia abortus is by ingesting the microorganism that has been eliminated in vaginal secretions, placental membranes or abortions that contaminate the environment and, possibly, through milk and colostrum. Elimination through vaginal secretions is well documented. However, there are no reports about isolation and identification of C. abortus in the colostrum or milk of infected sheep, so it is important to determine whether or not C. abortus may be present in these secretions, which are the only food of lambs. Objective: To detect C. abortus in colostrum, milk, and vaginal secretions of sheep with a history of reproductive disorders. Methods: Colostrum, milk, and vaginal exudates were collected from 66 sheep. The samples were inoculated in mouse fibroblast cell cultures and the presence of C. abortus determined by direct immunofluorescence. Results: 19 out of 66 colostrum samples (28.7%), 14 out of 66 milk samples (21.2%) and 17 out of 66 vaginal swabs (25.7%) were positive for C. abortus. The 50 samples positive for isolation and detected by immunofluorescence, together with 42 negative samples were subjected to qPCR to amplify a fragment of the ompA gene from C. abortus. Thirty-eight of the 92 samples processed by this technique were positive for C. abortus. Conclusion: The results demonstrated the presence of C. abortus in a high proportion in colostrum, milk and vaginal secretions of infected sheep. To the best of our knowledge, this is the first field study confirming the presence of C. abortus in colostrum, which shows that excretion of Chlamydia by lactogenesis could occur in the first hours after birth.
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Turin L, Surini S, Wheelhouse N, Rocchi MS. Recent advances and public health implications for environmental exposure to Chlamydia abortus: from enzootic to zoonotic disease. Vet Res 2022; 53:37. [PMID: 35642008 PMCID: PMC9152823 DOI: 10.1186/s13567-022-01052-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 03/29/2022] [Indexed: 11/24/2022] Open
Abstract
Environmental transmission of Chlamydia abortus as a result of enzootic disease or disease outbreaks and the threats posed by this pathogen has been previously reported, however a state-of-the-science review of these reports and the identification of future research priorities in this area is still lacking. This study provides an overview of the current knowledge of host–pathogen–environment interactions, addressing public health risks and identifying critical questions and research gaps. We performed a systematic PubMed and Web of Science search for publications related to Chlamydia abortus in the past four decades, and we reviewed and combined the evidence critically discussing and commenting the results. A total of 182 studies, 5 chapters of specific books and the “OIE terrestrial manual” were included in this review. There were substantial variations between the studies in topic addressed and experimental design. Overall, the literature largely supports the crucial role played by environmental exposure on the acquisition of zoonotic disease caused by Chlamydia abortus. We also identify the paucity of information related to interspecies transmission and pathogen adaptation in relation to environmental dissemination and zoonotic risk. This analysis further highlights the need for additional research given that environmental transmission represents a serious risk not only to susceptible patients (pregnant women and immunocompromised individuals), but also for other species including wildlife.
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Affiliation(s)
- Lauretta Turin
- Department of Veterinary Medicine (DIMEVET), University of Milan, Milan, Italy.
| | - Sara Surini
- Department of Veterinary Medicine (DIMEVET), University of Milan, Milan, Italy
| | - Nick Wheelhouse
- School of Applied Sciences, Edinburgh Napier University, Sighthill Court, Edinburgh, EH11 4BN, UK
| | - Mara Silvia Rocchi
- Moredun Research Institute, Bush Loan, Pentlands Science Park, Penicuik, EH26 0PZ, Scotland, UK
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Martínez-Serrano MG, Palomares-Reséndiz G, Tórtora-Pérez JL, Ramírez-Álvarez H, Ortega-Hernández N, Salinas-Lorente J, Morales-Alvarez JF, Cervantes-Morali JJC, Díaz-Aparicio E. Presence of Chlamydia abortus in colostrum, milk and vaginal discharge samples of sheep. REV COLOMB CIENC PEC 2021. [DOI: 10.17533/udea.rccp.v35n2a04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Livingstone M, Wattegedera SR, Palarea-Albaladejo J, Aitchison K, Corbett C, Sait M, Wilson K, Chianini F, Rocchi MS, Wheelhouse N, Entrican G, Longbottom D. Efficacy of Two Chlamydia abortus Subcellular Vaccines in a Pregnant Ewe Challenge Model for Ovine Enzootic Abortion. Vaccines (Basel) 2021; 9:vaccines9080898. [PMID: 34452023 PMCID: PMC8402522 DOI: 10.3390/vaccines9080898] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/02/2021] [Accepted: 08/11/2021] [Indexed: 11/24/2022] Open
Abstract
Chlamydia abortus, the aetiological agent of enzootic abortion of ewes, is a major cause of reproductive loss in small ruminants worldwide, accounting for significant economic losses to the farming industry. Disease can be managed through the use of commercial inactivated or live whole organism-based vaccines, although both have limitations particularly in terms of efficacy, safety and disease-associated outbreaks. Here we report a comparison of two experimental vaccines (chlamydial outer membrane complex (COMC) and octyl glucoside (OG)-COMC) based on detergent extracted outer membrane preparations of C. abortus and delivered as prime-boost immunisations, with the commercial live vaccine Cevac® Chlamydia in a pregnant sheep challenge model. No abortions occurred in either experimental vaccine group, while a single abortion occurred in the commercial vaccine group. Bacterial shedding, as a measure of potential risk of transmission of infection to naïve animals, was lowest in the COMC vaccinated group, with reductions of 87.5%, 86.4% and 74% observed for the COMC, OG-COMC and live commercial vaccine groups, respectively, compared to the unvaccinated challenge control group. The results show that the COMC vaccine performed the best and is a safer efficacious alternative to the commercial vaccines. However, to improve commercial viability, future studies should optimise the antigen dose and number of inoculations required.
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Affiliation(s)
- Morag Livingstone
- Moredun Research Institute, Pentlands Science Park, Midlothian EH26 0PZ, UK; (M.L.); (S.R.W.); (K.A.); (C.C.); (M.S.); (K.W.); (F.C.); (M.S.R.); (N.W.); (G.E.)
| | - Sean Ranjan Wattegedera
- Moredun Research Institute, Pentlands Science Park, Midlothian EH26 0PZ, UK; (M.L.); (S.R.W.); (K.A.); (C.C.); (M.S.); (K.W.); (F.C.); (M.S.R.); (N.W.); (G.E.)
| | | | - Kevin Aitchison
- Moredun Research Institute, Pentlands Science Park, Midlothian EH26 0PZ, UK; (M.L.); (S.R.W.); (K.A.); (C.C.); (M.S.); (K.W.); (F.C.); (M.S.R.); (N.W.); (G.E.)
| | - Cecilia Corbett
- Moredun Research Institute, Pentlands Science Park, Midlothian EH26 0PZ, UK; (M.L.); (S.R.W.); (K.A.); (C.C.); (M.S.); (K.W.); (F.C.); (M.S.R.); (N.W.); (G.E.)
| | - Michelle Sait
- Moredun Research Institute, Pentlands Science Park, Midlothian EH26 0PZ, UK; (M.L.); (S.R.W.); (K.A.); (C.C.); (M.S.); (K.W.); (F.C.); (M.S.R.); (N.W.); (G.E.)
| | - Kim Wilson
- Moredun Research Institute, Pentlands Science Park, Midlothian EH26 0PZ, UK; (M.L.); (S.R.W.); (K.A.); (C.C.); (M.S.); (K.W.); (F.C.); (M.S.R.); (N.W.); (G.E.)
| | - Francesca Chianini
- Moredun Research Institute, Pentlands Science Park, Midlothian EH26 0PZ, UK; (M.L.); (S.R.W.); (K.A.); (C.C.); (M.S.); (K.W.); (F.C.); (M.S.R.); (N.W.); (G.E.)
| | - Mara Silvia Rocchi
- Moredun Research Institute, Pentlands Science Park, Midlothian EH26 0PZ, UK; (M.L.); (S.R.W.); (K.A.); (C.C.); (M.S.); (K.W.); (F.C.); (M.S.R.); (N.W.); (G.E.)
| | - Nicholas Wheelhouse
- Moredun Research Institute, Pentlands Science Park, Midlothian EH26 0PZ, UK; (M.L.); (S.R.W.); (K.A.); (C.C.); (M.S.); (K.W.); (F.C.); (M.S.R.); (N.W.); (G.E.)
| | - Gary Entrican
- Moredun Research Institute, Pentlands Science Park, Midlothian EH26 0PZ, UK; (M.L.); (S.R.W.); (K.A.); (C.C.); (M.S.); (K.W.); (F.C.); (M.S.R.); (N.W.); (G.E.)
| | - David Longbottom
- Moredun Research Institute, Pentlands Science Park, Midlothian EH26 0PZ, UK; (M.L.); (S.R.W.); (K.A.); (C.C.); (M.S.); (K.W.); (F.C.); (M.S.R.); (N.W.); (G.E.)
- Correspondence:
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Epidemiology of Chlamydia psittaci infections in pregnant Thoroughbred mares and foals. Vet J 2021; 273:105683. [PMID: 34148605 DOI: 10.1016/j.tvjl.2021.105683] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 04/19/2021] [Accepted: 04/21/2021] [Indexed: 02/07/2023]
Abstract
Late-term foal loss due to the traditional avian pathogen Chlamydia psittaci recently emerged as a threat to the Australian Thoroughbred industry. A longitudinal study of 14 stud farms was undertaken to better understand C. psittaci infection in pregnant mares and their foals by evaluating C. psittaci prevalence, equine herpesvirus-1 (EHV-1) co-infection, avian reservoirs, and potential risk factors. Mucosal swabs taken from 228 healthy pregnant mares and their foals were tested for C. psittaci and EHV-1 using species-specific qPCR assays. No foal loss was recorded due to either pathogen, and no mare tested positive to either C. psittaci or EHV-1. However, healthy newborn foals tested positive to both pathogens, at low levels, with 13.2% (n = 30/228) and 14.5% (n = 33/228) prevalence for C. psittaci and EHV-1, respectively. Co-infection occurred in 1.3% (n = 3/228) of foals. In avian environmental faecal samples collected from the same studs, C. psittaci was detected at 5.3% (n = 5/94). Multiple logistic regression modelling found that foals born in winter were more likely to be infected with C. psittaci (adjusted odds ratio = 15.83; P < 0.001; Confidence Interval 5.12-48.49). Being a maiden mare, absence of prophylactic vaginal suture, interventions in the last trimester and residing on a farm with prior history of C. psittaci abortion posed no higher risk to infection in the newborn. Analysis of all reported C. psittaci abortion cases (Hunter Valley, 2016-2019) revealed a dominant C. psittaci sequence type (denoted ST24) and a significant correlation with frost events (Spearmans' rho = 0.44; P = 0.002).
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O'Neill LM, Keane OM, Ross PJ, Nally JE, Seshu J, Markey B. Evaluation of protective and immune responses following vaccination with recombinant MIP and CPAF from Chlamydia abortus as novel vaccines for enzootic abortion of ewes. Vaccine 2019; 37:5428-5438. [PMID: 31375438 DOI: 10.1016/j.vaccine.2019.06.088] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 06/26/2019] [Accepted: 06/28/2019] [Indexed: 11/18/2022]
Abstract
MIP and CPAF from Chlamydia have been shown to be effective in inducing immune responses important in clearing chlamydial infections. This study evaluates the protection conferred by MIP and CPAF as novel vaccines in pregnant C. abortus challenged ewes. Fifty C. abortus sero-negative sheep were randomly allocated into 5 groups of 10 according to the treatment they were to receive (1) 100 µg of MBP-MIP (2) 100 µg CPAF (3) 50 µg MBP-MIP and 50 µg CPAF (4) Tris-buffer (negative control) (5) Enzovax (positive control). Booster inoculations were administered 3 weeks after primary inoculations. Blood samples were taken pre-vaccination and weekly for 5 weeks. Five months after vaccination the ewes were mated. Pregnant ewes were then challenged on day 90 of gestation. Blood samples taken at four time-points post challenge were analysed for IFNγ levels, TNFα and IL-10 expression and anti-chlamydial antibody levels. Vaginal swabs, placental and foetal tissue and bacterial shedding were analysed using qPCR to quantify levels of C. abortus. Enzovax was 100% effective with no abortions occurring. The MIP/CPAF combined vaccine offered the greatest protection of the novel vaccines with 67% of ewes giving birth to one or more live lambs equating to a 50% vaccine efficacy rate. MIP and CPAF administered singly did not confer protection. Enzovax and MIP/CPAF vaccinated ewes had longer gestations and lambs with higher birth weights than negative control ewes. Aborting ewes shed higher numbers of C. abortus than ewes that had live lambs, all vaccinated ewes demonstrated lower levels of bacterial shedding than negative control ewes with Enzovax ewes shedding significantly fewer bacteria. Ewes that went on to abort had significantly higher levels of IFNγ and IL-10 at day 35 post challenge and significantly higher levels of anti-chlamydial antibodies at 24 h post lambing compared to ewes that had live lambs.
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Affiliation(s)
- L M O'Neill
- School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland; Animal & Bioscience Department, Teagasc Grange, Dunsany, Co. Meath, Ireland.
| | - O M Keane
- Animal & Bioscience Department, Teagasc Grange, Dunsany, Co. Meath, Ireland
| | - P J Ross
- Department of Agriculture, Food and the Marine, Central Veterinary Research Laboratory, Backweston, Co. Kildare, Ireland
| | - J E Nally
- Infectious Bacterial Diseases, National Animal Disease Center, Agriculture Research Service, United States Department of Agriculture, Ames, IA, USA
| | - J Seshu
- South Texas Center for Emerging Infectious Diseases, Centre of Excellence in Infection Genomics and Department of Biology, The University of Texas at San Antonio, San Antonio, TX, USA
| | - B Markey
- School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland
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O’Neill LM, O’Driscoll Á, Markey B. Comparison of three commercial serological tests for the detection of Chlamydia abortus infection in ewes. Ir Vet J 2018; 71:13. [PMID: 29854397 PMCID: PMC5975472 DOI: 10.1186/s13620-018-0124-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 05/10/2018] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND 20.9% of diagnosable abortions in Ireland in 2015 were caused by Chlamydia abortus infection. Abortion usually occurs in the last 2-3 weeks of gestation, and up to 30% of ewes may be affected in naïve flocks. Serological diagnosis of EAE in flocks using LPS or whole bacteria as antigens is often hindered by cross reactions with C. pecorum. Although the complement fixation test is the official test for diagnosis of EAE, more sensitive and specific ELISA based tests have been developed. This study aimed to compare three commercial ELISA kits to detect C. abortus antibodies in ewes and to determine which of the kits had the highest sensitivity. The IDvet kit utilises a MOMP peptide antigen, the MVD-Enfer kit is based on a POMP90-3 antigen while the LSI kit plates are coated with chlamydial LPS. The study also aimed to examine the potential of these ELISAs to distinguish infected animals that go on to abort compared to those that have live lambs. Ewes were vaccinated with either a commercial live vaccine (n = 10) or Tris-buffer sham inoculation (n = 9) 5 months prior to gestation, these ewes were then challenged with C. abortus (1 × 106 IFU/ml) on day 90 of gestation. Sera were collected at pre-vaccination, 14 days post vaccination, 35 days post vaccination, pre-challenge, 35 days post challenge and 3 weeks post lambing/abortion (~ 70 days post challenge) and tested using the 3 aforementioned ELISAs to determine if one ELISA was more sensitive at detecting circulating anti-chlamydial antibodies. RESULTS Sensitivity was highest with the LSI test kit at 94.74%, followed by the MVD-Enfer and IDvet kits, at 78.95 and 73.68% respectively. Ewes vaccinated with Enzovax became seropositive at 14 days post vaccination with all kits. Following challenge at day 90 of gestation, antibody titres steadily rose in all groups of ewes. With all ELISA kits, antibody levels were higher in ewes that aborted compared to ewes that had live lambs at 35 days post challenge and three weeks post lambing, and statistically significantly higher antibody levels were recorded in ewes that aborted compared to ewes that had live lambs using the MVD-ENFER ELISA at three weeks post lambing (P = 0.0482). CONCLUSIONS The LSI assay was the most sensitive out of the three kits tested in this study, when sera were tested at three weeks post lambing. As the LPS used in this kit is cross-reactive with all chlamydia, it is good for identifying flocks infected with any chlamydial species, but it is not considered specific for C. abortus. Furthermore, antibody levels were higher in ewes that aborted compared to ewes that had live lambs, at both 35 days post challenge and at three weeks post lambing. Future work should include evaluation of a larger number of sera at a wider range of time-points as well as an estimation of the specificity of commercially available assays.
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Affiliation(s)
- L. M. O’Neill
- School of Veterinary Medicine, University College Dublin, Room 07A, Belfield, Dublin 4, Ireland
| | - Á. O’Driscoll
- School of Veterinary Medicine, University College Dublin, Room 07A, Belfield, Dublin 4, Ireland
| | - B. Markey
- School of Veterinary Medicine, University College Dublin, Room 07A, Belfield, Dublin 4, Ireland
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García-Seco T, Pérez-Sancho M, Salinas J, Navarro A, Díez-Guerrier A, García N, Pozo P, Goyache J, Domínguez L, Álvarez J. Effect of Preventive Chlamydia abortus Vaccination in Offspring Development in Sheep Challenged Experimentally. Front Vet Sci 2016; 3:67. [PMID: 27610362 PMCID: PMC4997790 DOI: 10.3389/fvets.2016.00067] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 08/09/2016] [Indexed: 11/13/2022] Open
Abstract
Ovine enzootic abortion, caused by Chlamydia abortus, leads to important economic losses worldwide. In addition to reproductive failures, infection may impact lamb growth during the first weeks after birth, yet this effect has not been well characterized. Vaccination can help to control the disease but variable efficacy values have been described, possibly related with factors associated with the host, the vaccine, the parameter used for efficacy determination, and the challenge conditions. In this context, we evaluated the efficacy of an inactivated standard commercial vaccine and a 1/2 diluted dose in pregnant sheep challenged with C. abortus by examining multiple indicators of vaccine effect (including incidence of reproductive failures, bacterial excretion, and evolution of weight gain of viable lambs during the first month of life). Three groups of ewes [control non-vaccinated, C (n = 18); vaccinated with standard dose, SV (n = 16); and vaccinated with 1/2 dose, DV (n = 17)], were challenged approximately 90 days post-mating and tested using direct PCR (tissue samples and vaginal swabs) and ELISA (serum) until 31 days post-reproductive outcome. There were not significant differences in the proportions of reproductive failures or bacterial shedding after birth/abortion regardless the vaccination protocol. However, a beneficial effect of vaccination on offspring growth was detected in both vaccinated groups compared with the controls, with a mean increase in weight measured at 30 days of life of 1.5 and 2.5 kg (p = 0.056) and an increase in the geometric mean of the daily gain of 8.4 and 9.7% in lambs born from DV and SV ewes compared with controls, respectively. Our results demonstrate the effect of an inactivated vaccine in the development of the offspring of C. abortus-infected ewes at a standard and a diluted dose, an interesting finding given the difficulty in achieving sufficient antigen concentration in the production of enzootic abortion of ewes-commercial vaccines.
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Affiliation(s)
- Teresa García-Seco
- Centro de Vigilancia Sanitaria Veterinaria (VISAVET), Universidad Complutense de Madrid , Madrid , Spain
| | - Marta Pérez-Sancho
- Centro de Vigilancia Sanitaria Veterinaria (VISAVET), Universidad Complutense de Madrid, Madrid, Spain; Campus de Excelencia Internacional (CEI) Moncloa, Universidad Politécnica de Madrid (UPM)-Universidad Complutense de Madrid (UCM), Madrid, Spain
| | - Jesús Salinas
- Departamento de Sanidad Animal, Facultad de Veterinaria, Regional Campus of International Excellence 'Campus Mare Nostrum', Universidad de Murcia , Murcia , Spain
| | - Alejandro Navarro
- Centro de Vigilancia Sanitaria Veterinaria (VISAVET), Universidad Complutense de Madrid , Madrid , Spain
| | | | - Nerea García
- Centro de Vigilancia Sanitaria Veterinaria (VISAVET), Universidad Complutense de Madrid , Madrid , Spain
| | - Pilar Pozo
- Centro de Vigilancia Sanitaria Veterinaria (VISAVET), Universidad Complutense de Madrid , Madrid , Spain
| | - Joaquín Goyache
- Centro de Vigilancia Sanitaria Veterinaria (VISAVET), Universidad Complutense de Madrid, Madrid, Spain; Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid, Spain
| | - Lucas Domínguez
- Centro de Vigilancia Sanitaria Veterinaria (VISAVET), Universidad Complutense de Madrid, Madrid, Spain; Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid, Spain
| | - Julio Álvarez
- Department of Veterinary Population Medicine, University of Minnesota , Saint Paul, MN , USA
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Oseikria M, Pellerin JL, Rodolakis A, Vorimore F, Laroucau K, Bruyas JF, Roux C, Michaud S, Larrat M, Fieni F. Can Chlamydia abortus be transmitted by embryo transfer in goats? Theriogenology 2016; 86:1482-1488. [PMID: 27341774 DOI: 10.1016/j.theriogenology.2016.05.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 05/10/2016] [Accepted: 05/11/2016] [Indexed: 10/21/2022]
Abstract
The objectives of this study were to determine (i) whether Chlamydia abortus would adhere to or penetrate the intact zona pellucida (ZP-intact) of early in vivo-derived caprine embryos, after in vitro infection; and (ii) the efficacy of the International Embryo Transfer Society (IETS) washing protocol for bovine embryos. Fifty-two ZP-intact embryos (8-16 cells), obtained from 14 donors were used in this experiment. The embryos were randomly divided into 12 batches. Nine batches (ZP-intact) of five embryos were incubated in a medium containing 4 × 10(7)Chlamydia/mL of AB7 strain. After incubation for 18 hours at 37 °C in an atmosphere of 5% CO2, the embryos were washed in batches in 10 successive baths of a phosphate buffer saline and 5% fetal calf serum solution in accordance with IETS guidelines. In parallel, three batches of ZP-intact embryos were used as controls by being subjected to similar procedures but without exposure to C. abortus. The 10 wash baths were collected separately and centrifuged for 1 hour at 13,000 × g. The washed embryos and the pellets of the 10 centrifuged wash baths were frozen at -20 °C before examination for evidence of C. abortus using polymerase chain reaction. C. abortus DNA was found in all of the infected batches of ZP-intact embryos (9/9) after 10 successive washes. It was also detected in the 10th wash fluid for seven batches of embryos, whereas for the two other batches, the last positive wash bath was the eighth and the ninth, respectively. In contrast, none of the embryos or their washing fluids in the control batches were DNA positive. These results report that C. abortus adheres to and/or penetrates the ZP of in vivo caprine embryos after in vitro infection, and that the standard washing protocol recommended by the IETS for bovine embryos, failed to remove it. The persistence of these bacteria after washing makes the embryo a potential means of transmission of the bacterium during embryo transfer from infected donor goats to healthy recipients and/or their offspring. Nevertheless, the detection of C. abortus DNA by polymerase chain reaction does not prove that the bacteria found was infectious. Further studies are required to investigate whether enzymatic and/or antibiotic treatment of caprine embryos infected by C. abortus would eliminate the bacteria from the ZP.
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Affiliation(s)
- M Oseikria
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France
| | - J L Pellerin
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France
| | - A Rodolakis
- INRA, Animal Infectious Diseases and Public Health, Tours, France
| | - F Vorimore
- ANSES, Animal Health Laboratory, Bacterial Zoonosis Unit, Maisons-Alfort, France
| | - K Laroucau
- ANSES, Animal Health Laboratory, Bacterial Zoonosis Unit, Maisons-Alfort, France
| | - J F Bruyas
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France
| | - C Roux
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France
| | - S Michaud
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France
| | - M Larrat
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France
| | - F Fieni
- LUNAM University, Oniris, Nantes-Atlantic National College of Veterinary Medicine, Food Science and Engineering, Sanitary Security of Reproduction Biotechnology Unit, Nantes, France.
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Doull L, Wattegedera SR, Longbottom D, Mwangi D, Nath M, Glass EJ, Entrican G. Late production of CXCL8 in ruminant oro-nasal turbinate cells in response to Chlamydia abortus infection. Vet Immunol Immunopathol 2015; 168:97-102. [PMID: 26342452 DOI: 10.1016/j.vetimm.2015.08.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 08/06/2015] [Accepted: 08/26/2015] [Indexed: 11/15/2022]
Abstract
Chlamydia abortus is an obligate intracellular bacterium that is an important cause of ovine abortion worldwide. There are reports of abortions in cattle, but these are very rare compared to the reported incidence in sheep. The bacterium is transmitted oro-nasally and can establish a sub-clinical infection until pregnancy, when it can invade the placenta and induce an inflammatory cascade leading to placentitis and abortion. Early host-pathogen interactions could explain differential pathogenesis and subsequent disease outcome in ruminant species. In this study, we assessed the ability of sheep and cattle oro-nasal turbinate cells to sense and respond to C. abortus infection. The cells expressed toll like receptor (TLR) 2, TLR4, nucleotide oligomerization domain (NOD) 1 and NOD-like receptor pyrin domain containing 3 (NLRP3) mRNA. In response to C. abortus infection, both ovine and bovine turbinate cells produce CXCL8 mRNA and protein late in the bacterial developmental cycle, but do not produce IL-1β or TNF-α. The UV-inactivated bacteria did not elicit a CXCL8 response, suggesting that intracellular multiplication of the bacteria is important for activating the signalling pathways. The production of innate immune cytokines from cattle and sheep turbinate cells in response to C. abortus infection was found to be largely similar.
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Affiliation(s)
- L Doull
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Edinburgh EH26 0PZ, Scotland, UK; The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - S R Wattegedera
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Edinburgh EH26 0PZ, Scotland, UK
| | - D Longbottom
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Edinburgh EH26 0PZ, Scotland, UK
| | - D Mwangi
- Zoetis, 333 Portage Street, KZO-300-385.6SE, Kalamazoo, MI 49007, USA
| | - M Nath
- Biomathematics and Statistics Scotland, JCMB, The King's Buildings, Peter Guthrie Tait Road, Edinburgh EH9 3FD, UK
| | - E J Glass
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - G Entrican
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Edinburgh EH26 0PZ, Scotland, UK; The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK.
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15
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McNeilly TN, Rocchi M, Bartley Y, Brown JK, Frew D, Longhi C, McLean L, McIntyre J, Nisbet AJ, Wattegedera S, Huntley JF, Matthews JB. Suppression of ovine lymphocyte activation by Teladorsagia circumcincta larval excretory-secretory products. Vet Res 2013; 44:70. [PMID: 23964850 PMCID: PMC3848371 DOI: 10.1186/1297-9716-44-70] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 07/29/2013] [Indexed: 11/20/2022] Open
Abstract
Teladorsagia circumcincta is an important pathogenic nematode of sheep. It has been demonstrated previously that stimulation of murine T lymphocytes with excretory-secretory (ES) products derived from fourth stage larvae of T. circumcincta (Tci-L4-ES) results in de novo expression of Foxp3, a transcription factor intimately involved in regulatory T cell function. In the current study, Foxp3+ T cell responses in the abomasum and the effects of Tci-L4-ES on ovine peripheral blood mononuclear cells (PBMC) following T. circumcincta infection were investigated. T. circumcincta infection resulted in a significant increase in numbers of abomasal Foxp3+ T cells, but not an increase in the proportion of T cells expressing Foxp3. Unlike in mice, Tci-L4-ES was incapable of inducing T cell Foxp3 expression but instead suppressed mitogen-induced and antigen-specific activation and proliferation of ovine PBMC in vitro. This effect was heat labile, suggesting that it is mediated by protein(s). Suppression was associated with up-regulation of interleukin-10 (IL-10) mRNA, and specific monoclonal antibody neutralisation of IL-10 resulted in a 50% reduction in suppression, indicating involvement of the IL-10 signaling pathway. Suppression was significantly reduced in PBMC isolated from T. circumcincta infected vs. helminth-naïve lambs, and this reduction in suppression was associated with an increase in Tci-L4-ES antigen-specific T cells within the PBMC. In conclusion, we have identified a mechanism by which T. circumcincta may modulate the host adaptive immune response, potentially assisting survival of the parasite within the host. However, the impact of Tci-L4-ES-mediated lymphocyte suppression during T. circumcincta infection remains to be determined.
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Affiliation(s)
- Tom N McNeilly
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, UK.
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16
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Longbottom D, Livingstone M, Maley S, van der Zon A, Rocchi M, Wilson K, Wheelhouse N, Dagleish M, Aitchison K, Wattegedera S, Nath M, Entrican G, Buxton D. Intranasal infection with Chlamydia abortus induces dose-dependent latency and abortion in sheep. PLoS One 2013; 8:e57950. [PMID: 23469113 PMCID: PMC3585262 DOI: 10.1371/journal.pone.0057950] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Accepted: 01/27/2013] [Indexed: 02/07/2023] Open
Abstract
Background Latency is a key feature of the animal pathogen Chlamydia abortus, where infection remains inapparent in the non-pregnant animal and only becomes evident during a subsequent pregnancy. Often the first sign that an animal is infected is abortion occurring late in gestation. Despite this, little is understood of the underlying mechanisms that control latency or the recrudescence of infection that occurs during subsequent pregnancy. The aim of this study was to develop an experimental model of latency by mimicking the natural route of infection through the intranasal inoculation of non-pregnant sheep with C. abortus. Methodology/Principal Findings Three groups of sheep (groups 1, 2 and 3) were experimentally infected with different doses of C. abortus (5×103, 5×105 and 5×107 inclusion forming units (IFU), respectively) prior to mating and monitored over 2 breeding cycles for clinical, microbiological, pathological, immunological and serological outcomes. Two further groups received either negative control inoculum (group 4a,b) or were inoculated subcutaneously on day 70 of gestation with 2×106 IFU C. abortus (group 5). Animals in groups 1, 2 and 5 experienced an abortion rate of 50–67%, while only one animal aborted in group 3 and none in group 4a,b. Pathological, microbiological, immunological and serological analyses support the view that the maternal protective immune response is influenced by initial exposure to the bacterium. Conclusions/Significance The results show that intranasal administration of non-pregnant sheep with a low/medium dose of C. abortus results in a latent infection that leads in a subsequent pregnancy to infection of the placenta and abortion. In contrast a high dose stimulates protective immunity, resulting in a much lower abortion rate. This model will be useful in understanding the mechanisms of infection underlying latency and onset of disease, as well as in the development of novel therapeutics and vaccines for controlling infection.
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Entrican G, Wheelhouse N, Wattegedera SR, Longbottom D. New challenges for vaccination to prevent chlamydial abortion in sheep. Comp Immunol Microbiol Infect Dis 2011; 35:271-6. [PMID: 22209689 DOI: 10.1016/j.cimid.2011.12.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Revised: 12/05/2011] [Accepted: 12/06/2011] [Indexed: 10/14/2022]
Abstract
Ovine enzootic abortion (OEA) is caused by the obligate intracellular Gram-negative bacterium Chlamydia abortus. OEA remains a common cause of infectious abortion in many sheep-rearing countries despite the existence of commercially available vaccines that protect against the disease. There are a number of confounding factors that influence the uptake and use of these vaccines, which includes an inability to discriminate between infected and vaccinated animals (DIVA) using conventional serological diagnostic techniques. This suggests that the immunity elicited by current vaccines is similar to that observed in convalescent, immune sheep that have experienced OEA. The existence of these vaccines provides an opportunity to understand how protection against OEA is elicited and also to understand why vaccines can occasionally appear to fail, as has been reported recently for OEA. Interferon-gamma (IFN-γ), the cytokine that classically defines Th1-type adaptive immunity, is a strong correlate of protection against OEA in sheep and has been shown to inhibit the growth of C. abortus in vitro. Humoral immunity to C. abortus is observed in both vaccinated and naturally infected sheep, but antibody responses tend to be used more as diagnostic markers than targets for strategic vaccine design. A future successful DIVA vaccine against OEA should aim to elicit the immunological correlate of protection (IFN-γ) concomitantly with an antibody profile that is distinct from that of the natural infection. Such an approach requires careful selection of protective components of C. abortus combined with an effective delivery system that elicits IFN-γ-producing CD4+ve memory T cells.
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Affiliation(s)
- Gary Entrican
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Midlothian, EH26 0PZ Scotland, United Kingdom.
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18
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Control of Important Causes of Infectious Abortion in Sheep and Goats. Vet Clin North Am Food Anim Pract 2011; 27:81-93. [DOI: 10.1016/j.cvfa.2010.10.011] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Entrican G, Wattegedera S, Wheelhouse N, Allan A, Rocchi M. Immunological paradigms and the pathogenesis of ovine chlamydial abortion. Am J Reprod Immunol 2010; 64:287-94. [PMID: 20712809 DOI: 10.1111/j.1600-0897.2010.00907.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Successful mammalian pregnancy involves complex immunological interactions between the mother and foetus that are not yet fully understood. A number of immunological paradigms have been established to explain the failure of the maternal immune system to reject the semi-allogeneic foetus, mainly based on studies in mice and humans. However, as placental structure, gestation periods and number of concepti per pregnancy can vary greatly between mammals, it is not always clear how applicable these immunological paradigms are to reproduction in other species. Here, we discuss the predictions of three important immunological paradigms in relation to the pathogenesis of ovine enzootic abortion (OEA), a common cause of infectious abortion in sheep and other ruminants. OEA is caused by the intracellular Gram-negative bacterium Chlamydophila abortus that exhibits a tropism for placental trophoblast. The paradigms of particular relevance to the pathogenesis of OEA are as follows: (i) intracellular bacterial infections are controlled by T(H)1-type CD4(+ve) T cells; (ii) indoleamine 2,3-dioxygenase is expressed in the placenta to prevent immunological rejection of the semi-allogeneic foetus; and (iii) pregnancy is a maternal T(H)2-type phenomenon. We discuss the relevance and validity of these paradigms for chlamydial abortion and reproductive immunology in sheep.
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Affiliation(s)
- Gary Entrican
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Edinburgh, Scotland, UK.
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20
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Inflammatory cytokine responses in a pregnant mouse model of Chlamydophila abortus infection. Vet Microbiol 2010; 144:392-8. [DOI: 10.1016/j.vetmic.2010.01.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2009] [Revised: 01/26/2010] [Accepted: 01/28/2010] [Indexed: 11/22/2022]
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21
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Gutierrez J, Williams EJ, O'Donovan J, Brady C, Proctor AF, Marques PX, Worrall S, Nally JE, McElroy M, Bassett HF, Sammin DJ, Markey BK. Monitoring clinical outcomes, pathological changes and shedding of Chlamydophila abortus following experimental challenge of periparturient ewes utilizing the natural route of infection. Vet Microbiol 2010; 147:119-26. [PMID: 20638204 DOI: 10.1016/j.vetmic.2010.06.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2010] [Revised: 06/09/2010] [Accepted: 06/14/2010] [Indexed: 10/19/2022]
Abstract
Enzootic abortion of ewes (EAE) caused by Chlamydophila abortus is an important disease resulting in significant lamb loss in most sheep producing countries. Ewes are considered to be naturally infected with C. abortus via the oral-nasal route and may become persistent carriers, shedding during subsequent oestrous cycles and at lambing. The aim of this study was to monitor the clinical outcomes, pathological changes and shedding of C. abortus in 18 periparturient orally infected sheep for two breeding seasons. In the first season, C. abortus was detected by real-time PCR (rt-PCR) in 13/18 conjunctival swabs at oestrus. Three out of the 15 pregnant ewes gave birth to 1 live and 1 dead lamb, and 2 of them aborted. Following parturition/abortion, C. abortus was detected in 12/15 vaginal swabs and in all the collected foetal membranes. However, only those membranes containing high copy numbers of the bacterium displayed the EAE typical lesions. In the second season, none of the 13 pregnant ewes aborted, and 5 of them gave birth to dead or weak lambs. C. abortus was not detected in conjunctival or vaginal swabs at oestrus or parturition. The bacterium was detected at low levels in 36% of the foetal membranes, but with no evidence of histopathological lesions. These results indicate that C. abortus can be detected in a large proportion of animals during the first pregnancy after oral infection. However, this proportion is reduced at the subsequent breeding season, confirming the occurrence of a chronic low level persistent infection in post-abortion/lambing ewes.
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Affiliation(s)
- Jorge Gutierrez
- School of Agriculture, Food Science and Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland.
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Wattegedera SR, Watson DM, Hope JC, Kaiser P, Sales J, McInnes CJ, Entrican G. Relative quantitative kinetics of interferon-gamma and interleukin-10 mRNA and protein production by activated ovine peripheral blood mononuclear cells. Vet Immunol Immunopathol 2010; 136:34-42. [PMID: 20197203 DOI: 10.1016/j.vetimm.2010.02.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2009] [Revised: 02/02/2010] [Accepted: 02/02/2010] [Indexed: 10/19/2022]
Abstract
Interferon-gamma (IFN-gamma) and interleukin (IL)-10 are cross-regulatory cytokines capable of driving and controlling the adaptive host immune response. The inter-relationship between IFN-gamma and IL-10 expression has not been defined in sheep despite biological evidence suggesting that they perform similar functions to their orthologues described in other species. To address this, we have developed a quantitative (q)PCR method to assess relative levels of IFN-gamma and IL-10 mRNA expression in activated ovine peripheral blood mononuclear cells (PBMC) and compared the kinetics of mRNA expression with amounts of cytokine secreted by the cells over a 96h period. PBMC were collected from sheep immunised with the nominal antigen ovalbumin (Ova) and re-stimulated in vitro with antigen and the T cell mitogen concanavalin A (ConA). The recall response to antigen was characterised by a single peak in IFN-gamma mRNA expression at 48h of culture (13-fold increase over unstimulated cells) and relatively lower expression of IL-10 mRNA (average 2-3-fold increase over the 96h culture period). Antigen-driven IFN-gamma protein concentration was greatest at the end of the culture period (96h) whereas IL-10 protein level was not elevated above that observed in unstimulated cells. The typical response to ConA was greater for both cytokines, with IFN-gamma mRNA expression peaking at 6h of culture (133-fold increase) then declining rapidly whereas IL-10 mRNA expression peaked at 24h (16-fold increase) and declined more gradually. Despite these differences in the relative kinetics of mRNA expression in mitogen-activated PBMC, the typical pattern of protein expression of the two cytokines was similar. Both showed a gradual rise in protein concentration starting from 12h of culture which was still rising at the end of the culture period (96h). These data demonstrate that the kinetics of mRNA expression for IFN-gamma and IL-10 in activated ovine PBMC do not necessarily correlate with detectable protein in culture.
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Affiliation(s)
- S R Wattegedera
- Moredun Research Institute, International Research Centre, Pentlands Science Park, Bush Loan, Penicuik, Midlothian EH26 0PZ, UK.
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23
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Wheelhouse N, Wattegedera S, Stanton J, Maley S, Watson D, Jepson C, Deane D, Buxton D, Longbottom D, Baszler T, Entrican G. Ovine trophoblast is a primary source of TNFα during Chlamydophila abortus infection. J Reprod Immunol 2009; 80:49-56. [DOI: 10.1016/j.jri.2008.12.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2008] [Revised: 12/10/2008] [Accepted: 12/11/2008] [Indexed: 01/19/2023]
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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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25
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Entrican G, Wattegedera S, Rocchi M, Wheelhouse N. Pregnancy, indoleamine 2,3-dioxygenase (IDO) and chlamydial abortion: An unresolved paradox. Vet Microbiol 2009; 135:98-102. [DOI: 10.1016/j.vetmic.2008.09.028] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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