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Daisy Vanrompay - One of the best experts on this subject based on the ideXlab platform.

  • Chlamydophila Psittaci in homing and feral pigeons and zoonotic transmission.
    Journal of medical microbiology, 2010
    Co-Authors: V Dickx, D S A Beeckman, L Dossche, P Tavernier, Daisy Vanrompay
    Abstract:

    Chlamydiosis is a zoonotic disease in birds caused by Chlamydophila Psittaci, an obligate intracellular bacterium. There are seven known avian outer-membrane protein A genotypes, A-F and E/B. The importance of genotyping lies in the fact that certain genotypes tend to be associated with certain hosts and a difference in virulence. Genotype B is the most prevalent in pigeons, but the more virulent genotypes A and D have also been discovered. The current study assessed the prevalence of C. Psittaci in 32 Belgian homing-pigeon facilities and in 61 feral pigeons captured in the city of Ghent, Belgium. Additionally, zoonotic transmission of C. Psittaci was investigated in the homing-pigeon facilities. Homing pigeons were often infected, as at least one of the lofts was positive in 13 of the 32 (40.6 %) pigeon breeding facilities. Genotypes B, C and D were detected. Zoonotic transmission was discovered in 4 of the 32 (12.5 %) pigeon fanciers, revealing genotype D in two of them, whilst genotyping was unsuccessful for the other two human pharyngeal swabs. This study clearly demonstrates the possible risk of C. Psittaci zoonotic transmission from homing pigeons. Pigeon fanciers often (37.5 %) used antibiotics for prevention of respiratory disease. Because of the risk of developing drug-resistant strains, regular use of antimicrobial drugs must be avoided. This study is believed to be the first to detect C. Psittaci in Belgian feral pigeons. The prevalence rate in the city of Ghent was extremely low, which is beneficial for public health.

  • Chlamydophila Psittaci Zoonotic Risk Assessment in a Chicken and Turkey Slaughterhouse
    Journal of clinical microbiology, 2010
    Co-Authors: Veerle Dickx, Taher Harkinezhad, Delphine Sylvie Anne Beeckman, Lutgart Braeckman, Tom Geens, Thomas P.g. Deschuyffeleer, Laurent Tyberghien, Daisy Vanrompay
    Abstract:

    Chlamydophila Psittaci causes respiratory disease in poultry and can be transmitted to humans. We conducted a C. Psittaci zoonotic risk assessment study of a chicken and turkey slaughterhouse. Eighty-five percent of the slaughtered chicken flocks tested positive by PCR and culture. Genotype D was discovered. Fifty-seven percent of the slaughtered turkey flocks tested positive by PCR and culture. Genotype D was present. For the chicken slaughterhouse employees, 7.5% and 6% tested positive for C. Psittaci by PCR and culture, respectively. In the turkey slaughterhouse, 87% and 61% of the employees tested positive by PCR and culture, respectively. All genotyped human samples contained genotype D. Using stationary bioaerosol monitoring by means of an MAS-100 ecosampler and ChlamyTrap collection medium, chlamydial DNA, and viable organisms were detected in both the chicken and turkey slaughterhouses. Positive air samples were most frequently found in the animal reception area and evisceration room. Zoonotic transmissions were very common, especially from processed turkeys. Accurate diagnostic monitoring and reporting of C. Psittaci infections should be promoted in poultry workers.

  • Chlamydophila Psittaci infections in turkeys: overview of economic and zoonotic importance and vaccine development.
    Drugs of Today, 2009
    Co-Authors: Kristel Verminnen, Daisy Vanrompay
    Abstract:

    We provide evidence on the multifactorial infectious etiology of respiratory disease in turkeys. Although Chlamydophila Psittaci is difficult to diagnose, this entity should not be neglected in veterinary diagnostic laboratories. The present results suggest a pathogenic interplay between Chlamydophila, avian metapneumovirus and Ornithobacterium rhinotracheale. Additionally, we demonstrate zoonotic transmission from turkeys to humans. Psittacosis due to contact with poultry probably occurs more often than is thought and the infection can be asymptomatic or symptomatic. There is no commercial C. Psittaci vaccine available and currently the best option is an experimental major outer membrane protein-based DNA vaccine.

  • Protection of budgerigars (Melopsittacus undulatus) against Chlamydophila Psittaci challenge by DNA vaccination
    Veterinary Research, 2009
    Co-Authors: Taher Harkinezhad, Katelijn Schautteet, Daisy Vanrompay
    Abstract:

    Plasmid DNA (pcDNA1::MOMP A) expressing the major outer membrane protein (MOMP) of Chlamydophila Psittaci genotype A strain 89/1051 has been tested for its ability to induce protective immunity against Cp. Psittaci challenge in budgerigars. Eight pairs of male and female budgerigars were housed in eight separate bird cages placed in two negative pressure isolators, four cages per group. All budgerigars were immunised twice intramuscularly with 100 μg plasmid DNA. Both groups received a primary DNA inoculation at day 0 followed by a booster inoculation 3 weeks later. Group 1 received pcDNA1::MOMP A, while group 2 received the placebo vaccine pcDNA1. Budgerigars were challenged by aerosol 2 weeks following the booster vaccination. The challenge consisted of 108 TCID50 of the homologous Cp. Psittaci genotype A strain. Cloacal and pharyngeal swabs of all budgerigars, taken prior to the experimental infection were negative in both PCR and culture. However, all budgerigars showed low pre-existing serum antibody titres. This indicates that animals were previously infected. Nevertheless, DNA immunisation could significantly reduce clinical signs, macroscopic lesions, pharyngeal and cloacal excretion as well as chlamydial replication, even in the presence of pre-existing serum antibodies, as compared to the placebo-vaccinated controls.

  • Zoonotic Chlamydophila Psittaci infections from a clinical perspective
    Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases, 2009
    Co-Authors: Delphine Sylvie Anne Beeckman, Daisy Vanrompay
    Abstract:

    Human psittacosis is a zoonotic infectious disease which is caused by the obligate intracellular bacterium Chlamydophila Psittaci. Transmission of the disease usually originates from close contact with infected birds, most frequently in the context of the poultry industry, and from contact with Psittaciformes (cockatoos, parrots, parakeets and lories). Due to a low awareness of the disease and a variable clinical presentation psittacosis is often not recognised as such by general practitioners. This review therefore gives an overview of the epidemiology, symptoms, diagnosis and possible treatments for psittacosis in humans. The current case definition for epidemiological surveillance, as issued by the CDC, is discussed, as well as the possible emergence of Cp. Psittaci antibiotic-resistant strains. There is an urgent need for information and for awareness campaigns directed at professional health care workers and the general public. In addition, a broader use of new diagnostic methods in medical laboratories and the development of prophylactics are called for.

Bruno Goddeeris - One of the best experts on this subject based on the ideXlab platform.

  • Exacerbation of Chlamydophila Psittaci pathogenicity in turkeys superinfected by Escherichia coli
    Veterinary research, 2006
    Co-Authors: M Van Loock, Daisy Vanrompay, Karolien Loots, Marjolein Van Heerden, Bruno Goddeeris
    Abstract:

    Both Chlamydophila Psittaci and Escherichia coli infections are highly prevalent in Belgian turkeys and therefore they both might contribute to the respiratory disease complex ob- served in turkeys. C. Psittaci can infect turkeys within the first week of age, even in the presence of maternal antibodies. However, the first C. Psittaci outbreaks occur mostly at the age of 3 to 6 weeks, the period when also E. coli infections appear on the farms. Therefore, we examined in this study the pathogenicity of an E. coli superinfection on C. Psittaci predisposed turkeys. Turkeys were in- fected with C. Psittaci, E. coli or with C. Psittaci followed by E. coli. Simulating the impact of an E. coli infection during the acute phase or the latent phase of a C. Psittaci infection, turkeys received E. coli at 1 or 5 weeks post C. Psittaci infection, respectively. E. coli superinfection during the acute phase of C. Psittaci infection increased C. Psittaci excretion and stimulated chlamydial replication in the respiratory tract resulting in exacerbated clinical disease. Interestingly, E. coli superinfection during the latent phase of C. Psittaci infection induced chlamydial replication, leading to increased C. Psittaci-specific antibody titres. In addition, chlamydial predisposition gave higher E. coli ex- cretion compared with turkeys that had only been infected with E. coli. Overall, the present study clearly demonstrates the pathogenic interplay between C. Psittaci and E. coli resulting in more severe respiratory disease. Chlamydophila Psittaci / Escherichia coli / turkeys

  • Evaluation of the persistence and gene expression of an anti-Chlamydophila Psittaci DNA vaccine in turkey muscle.
    BMC veterinary research, 2006
    Co-Authors: Karolien Loots, Daisy Vanrompay, Bart Vleugels, Ellen Ons, Bruno Goddeeris
    Abstract:

    Background DNA vaccination has been shown to elicit specific cellular and humoral immune responses to many different agents in a broad variety of species. However, looking at a commercial use, the duration of the immune response against the vaccine is critical. Therefore the persistence of the DNA vaccine, as well as its expression, should be investigated. We conducted these investigations on a DNA vaccine against Chlamydophila Psittaci, a Gram-negative intracellular bacterium which causes respiratory disease in turkeys and humans. Previous studies showed that the DNA vaccine confers partial protection against C. Psittaci infection in turkeys. Turkeys were injected intramuscularly with the DNA vaccine : a eukaryotic expression vector (pcDNA1::MOMP) expressing the major outer membrane protein (MOMP) of an avian C. Psittaci serovar D strain. Over a period of 11 weeks, cellular uptake of the DNA vaccine was examined by PCR, transcription of the insert by reverse transcript-PCR (RT-PCR) and mRNA translation by immunofluorescence staining of muscle biopsies.

  • pathogenic interactions between Chlamydophila Psittaci and avian pneumovirus infections in turkeys
    Veterinary Microbiology, 2006
    Co-Authors: M Van Loock, Bruno Goddeeris, Karolien Loots, Marjolein Van Heerden, S Van De Zande, Hans Nauwynck, Daisy Vanrompay
    Abstract:

    Both Chlamydophila Psittaci and avian pneumovirus (APV) are highly prevalent in Belgian turkeys and might contribute to the respiratory disease complex observed in turkeys. Initial outbreaks of chlamydiosis occur mostly at the age of 4-8 weeks, often accompanied by an APV infection in APV non-vaccinated farms. Regardless APV vaccination, breakthroughs of APV infection from 8 weeks on do occur, a period when also a second C. Psittaci infection appears. Therefore, this study examined the pathogenicity of an APV superinfection in C. Psittaci predisposed turkeys. Turkeys were infected with C. Psittaci, APV or with C. Psittaci followed by APV. Simulating the impact of an APV infection during the acute phase or latent phase of a C. Psittaci infection, turkeys have been infected with APV at 1 and 5 weeks post C. Psittaci infection, respectively. APV infection during the acute phase of a C. Psittaci infection aggravates the severity of clinical signs, macroscopic lesions, pharyngeal APV excretion and histological tracheae lesions. In contrast, no clear interaction could be established after APV infection in latently C. Psittaci infected specific pathogen-free (SPF) turkeys. This study clearly demonstrates the exacerbating role of APV during acute C. Psittaci infection, which can play an important role in the respiratory disease complex of turkeys.

  • Exacerbation of Chlamydophila Psittaci pathogenicity in turkeys superinfected by Escherichia coli
    Veterinary Research, 2006
    Co-Authors: M Van Loock, Daisy Vanrompay, Karolien Loots, Marjolein Van Heerden, Bruno Goddeeris
    Abstract:

    Both Chlamydophila Psittaci and Escherichia coli infections are highly prevalent in Belgian turkeys and therefore they both might contribute to the respiratory disease complex observed in turkeys. C. Psittaci can infect turkeys within the first week of age, even in the presence of maternal antibodies. However, the first C. Psittaci outbreaks occur mostly at the age of 3 to 6 weeks, the period when also E. coli infections appear on the farms. Therefore, we examined in this study the pathogenicity of an E. coli superinfection on C. Psittaci predisposed turkeys. Turkeys were infected with C. Psittaci, E. coli or with C. Psittaci followed by E. coli. Simulating the impact of an E. coli infection during the acute phase or the latent phase of a C. Psittaci infection, turkeys received E. coli at 1 or 5 weeks post C. Psittaci infection, respectively. E. coli superinfection during the acute phase of C. Psittaci infection increased C. Psittaci excretion and stimulated chlamydial replication in the respiratory tract resulting in exacerbated clinical disease. Interestingly, E. coli superinfection during the latent phase of C. Psittaci infection induced chlamydial replication, leading to increased C. Psittaci-specific antibody titres. In addition, chlamydial predisposition gave higher E. coli excretion compared with turkeys that had only been infected with E. coli. Overall, the present study clearly demonstrates the pathogenic interplay between C. Psittaci and E. coli resulting in more severe respiratory disease.

  • Use of a nested PCR-enzyme immunoassay with an internal control to detect Chlamydophila Psittaci in turkeys.
    BMC infectious diseases, 2005
    Co-Authors: M Van Loock, Bruno Goddeeris, Guido Volckaert, Kristel Verminnen, Trudy O Messmer, Daisy Vanrompay
    Abstract:

    Background Laboratory diagnosis of Chlamydophila Psittaci, an important turkey respiratory pathogen, is difficult. To facilitate the diagnosis, a nested PCR-enzyme immunoassay (PCR-EIA) was developed to detect the Cp. Psittaci outer membrane protein A (ompA) gene in pharyngeal swabs.

Delphine Sylvie Anne Beeckman - One of the best experts on this subject based on the ideXlab platform.

  • Chlamydophila Psittaci Zoonotic Risk Assessment in a Chicken and Turkey Slaughterhouse
    Journal of clinical microbiology, 2010
    Co-Authors: Veerle Dickx, Taher Harkinezhad, Delphine Sylvie Anne Beeckman, Lutgart Braeckman, Tom Geens, Thomas P.g. Deschuyffeleer, Laurent Tyberghien, Daisy Vanrompay
    Abstract:

    Chlamydophila Psittaci causes respiratory disease in poultry and can be transmitted to humans. We conducted a C. Psittaci zoonotic risk assessment study of a chicken and turkey slaughterhouse. Eighty-five percent of the slaughtered chicken flocks tested positive by PCR and culture. Genotype D was discovered. Fifty-seven percent of the slaughtered turkey flocks tested positive by PCR and culture. Genotype D was present. For the chicken slaughterhouse employees, 7.5% and 6% tested positive for C. Psittaci by PCR and culture, respectively. In the turkey slaughterhouse, 87% and 61% of the employees tested positive by PCR and culture, respectively. All genotyped human samples contained genotype D. Using stationary bioaerosol monitoring by means of an MAS-100 ecosampler and ChlamyTrap collection medium, chlamydial DNA, and viable organisms were detected in both the chicken and turkey slaughterhouses. Positive air samples were most frequently found in the animal reception area and evisceration room. Zoonotic transmissions were very common, especially from processed turkeys. Accurate diagnostic monitoring and reporting of C. Psittaci infections should be promoted in poultry workers.

  • Zoonotic Chlamydophila Psittaci infections from a clinical perspective
    Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases, 2009
    Co-Authors: Delphine Sylvie Anne Beeckman, Daisy Vanrompay
    Abstract:

    Human psittacosis is a zoonotic infectious disease which is caused by the obligate intracellular bacterium Chlamydophila Psittaci. Transmission of the disease usually originates from close contact with infected birds, most frequently in the context of the poultry industry, and from contact with Psittaciformes (cockatoos, parrots, parakeets and lories). Due to a low awareness of the disease and a variable clinical presentation psittacosis is often not recognised as such by general practitioners. This review therefore gives an overview of the epidemiology, symptoms, diagnosis and possible treatments for psittacosis in humans. The current case definition for epidemiological surveillance, as issued by the CDC, is discussed, as well as the possible emergence of Cp. Psittaci antibiotic-resistant strains. There is an urgent need for information and for awareness campaigns directed at professional health care workers and the general public. In addition, a broader use of new diagnostic methods in medical laboratories and the development of prophylactics are called for.

  • Examining the role of type III secretion in the biology and intracellular pathogenesis of Chlamydophila Psittaci
    2009
    Co-Authors: Delphine Sylvie Anne Beeckman
    Abstract:

    Chlamydiaceae are Gram-negative obligate intracellular bacteria and are therefore completely dependent on a living host cell to execute their unique biphasic developmental cycle. This is accompanied by a reprogramming of the host cell into a minimized factory efficiently supporting chlamydial replication. Type III secretion could be essential in this process as other Gram-negative bacteria deploy similar secretion mechanisms to subvert the cellular functions of their host to their own benefit. Chlamydophila Psittaci primarily infects birds and is horizontally transmitted through aerosols of nasal secretions and feces. Initially, the respiratory tract is infected, from where the disease further spreads leading to a systemic infection. The commercial poultry industry is affected by considerable economic losses, especially when the animals are simultaneously infected with avian pathogenic E. coli, Ornithobacterium rhinotracheale or avian metapneumovirus. Zoonotic transmission occurs in people in close contact with infected birds, the clinical outcome ranging from inapparent to severe flu-like symptoms or pneumonia. In this thesis, we have proven that a functional Type III secretion system is present in Chlamydophila Psittaci, involved in the entry and replication of chlamydial organisms. Using a newly developed digital titration assay, lactoferrin and especially ovotransferrin proved their usefulness as anti-chlamydial compounds, of which ovotransferrin is now being tested as a cost-effective prophylactic measure in large scale turkey farms. We have also shown that Chlamydophila Psittaci ompA genotype B strains invade, survive and replicate less efficiently in avian monocytes/macrophages compared to genotype A or D strains. Moreover, the induced cytokine responses are less pronounced, thus attracting fewer macrophages from the surrounding tissues. We postulate that mildly virulent strains disseminate less throughout the host, leading to more restricted lesions, hardly affecting the physical condition of the host. In addition, exceptionally high IL-10 and no TGF-β4 responses were observed, probably inducing a deactivation of monocytes/macrophages and inhibiting the pro-inflammatory and Th1 responses, resulting in a less efficient clearance of both Chlamydophila Psittaci and subsequent infections. However, Chlamydophila Psittaci has not yet revealed all of its secrets and more research is needed to unravel the remaining mysteries in its interaction with both the avian and the human host.

  • Identification and characterization of a type III secretion system in Chlamydophila Psittaci.
    Veterinary research, 2008
    Co-Authors: Delphine Sylvie Anne Beeckman, Tom Geens, Jean-pierre Timmermans, Patrick Van Oostveldt, Daisy Vanrompay
    Abstract:

    Chlamydiaceae are obligate intracellular Gram-negative bacteria replicating in vacuoles inside eukaryotic cells. It has been proven that most of them possess a type III secretion system (T3SS) allowing them to transfer effector molecules in the host cell. We examined the existence of a T3SS in Chlamydophila Psittaci by studying the expression of three essential structural proteins SctW, SctC, and SctN, and one putative effector protein IncA. Immunofluorescence assays showed SctW and IncA to be associated with the bacteria and the inclusion membrane, while SctC and SctN were only localized to the bacteria itself. Immuno electron microscopy could confirm these results for SctW, IncA, and SctC. Unfortunately, SctN was not investigated with this technique. Additionally, we sequenced 14 full-length T3S genes (scc1, sctW, sctJ, sctL, sctR, sctS, scc2, copD1, sctN, sctQ, sctC, incA, ca037, and cadd) and examined the transcription of 26 Cp. Psittaci T3S genes namely cluster 1 (scc1, sctW, sctV, sctU), cluster 2 (sctJ, sctL, sctR, sctS, sctT, scc2, copB1, copD1), cluster 3 (sctD, sctN, ca037, sctQ, pkn5, sctC) and non-clustered genes (incA, incC, scc3, copD2, cap1, tarp, ca530, cadd). The gene expression study indicated the T3S structural protein encoding genes to be transcribed from mid-cycle (12-18 h post infection (p.i.)) on. Genes encoding effector proteins and putative T3S related proteins were expressed early (1.5 h-8 h p.i.) or late (>24 h p.i.) during the developmental cycle. We hereby provided evidence for the existence of a T3SS and possible effectors in avian Cp. Psittaci.

  • Chlamydophila Psittaci Transmission from Pet Birds to Humans
    Emerging infectious diseases, 2007
    Co-Authors: Daisy Vanrompay, Taher Harkinezhad, Marijke Van De Walle, Delphine Sylvie Anne Beeckman, Caroline Van Droogenbroeck, Kristel Verminnen, Ruud Leten, An Martel, Katty Cauwerts
    Abstract:

    We studied zoonotic transmission of Chlamydophila Psittaci in 39 breeding facilities for Psittaciformes (cockatoos, parrots, parakeets, lories) that frequently used antimicrobial drugs. Genotypes A or E/B were detected in 14.9% of humans at these facilities. Information on antimicrobial drug use in Psittaciformes and a C. Psittaci vaccine are urgently required.

Tom Geens - One of the best experts on this subject based on the ideXlab platform.

  • Chlamydophila Psittaci Zoonotic Risk Assessment in a Chicken and Turkey Slaughterhouse
    Journal of clinical microbiology, 2010
    Co-Authors: Veerle Dickx, Taher Harkinezhad, Delphine Sylvie Anne Beeckman, Lutgart Braeckman, Tom Geens, Thomas P.g. Deschuyffeleer, Laurent Tyberghien, Daisy Vanrompay
    Abstract:

    Chlamydophila Psittaci causes respiratory disease in poultry and can be transmitted to humans. We conducted a C. Psittaci zoonotic risk assessment study of a chicken and turkey slaughterhouse. Eighty-five percent of the slaughtered chicken flocks tested positive by PCR and culture. Genotype D was discovered. Fifty-seven percent of the slaughtered turkey flocks tested positive by PCR and culture. Genotype D was present. For the chicken slaughterhouse employees, 7.5% and 6% tested positive for C. Psittaci by PCR and culture, respectively. In the turkey slaughterhouse, 87% and 61% of the employees tested positive by PCR and culture, respectively. All genotyped human samples contained genotype D. Using stationary bioaerosol monitoring by means of an MAS-100 ecosampler and ChlamyTrap collection medium, chlamydial DNA, and viable organisms were detected in both the chicken and turkey slaughterhouses. Positive air samples were most frequently found in the animal reception area and evisceration room. Zoonotic transmissions were very common, especially from processed turkeys. Accurate diagnostic monitoring and reporting of C. Psittaci infections should be promoted in poultry workers.

  • Identification and characterization of a type III secretion system in Chlamydophila Psittaci.
    Veterinary research, 2008
    Co-Authors: Delphine Sylvie Anne Beeckman, Tom Geens, Jean-pierre Timmermans, Patrick Van Oostveldt, Daisy Vanrompay
    Abstract:

    Chlamydiaceae are obligate intracellular Gram-negative bacteria replicating in vacuoles inside eukaryotic cells. It has been proven that most of them possess a type III secretion system (T3SS) allowing them to transfer effector molecules in the host cell. We examined the existence of a T3SS in Chlamydophila Psittaci by studying the expression of three essential structural proteins SctW, SctC, and SctN, and one putative effector protein IncA. Immunofluorescence assays showed SctW and IncA to be associated with the bacteria and the inclusion membrane, while SctC and SctN were only localized to the bacteria itself. Immuno electron microscopy could confirm these results for SctW, IncA, and SctC. Unfortunately, SctN was not investigated with this technique. Additionally, we sequenced 14 full-length T3S genes (scc1, sctW, sctJ, sctL, sctR, sctS, scc2, copD1, sctN, sctQ, sctC, incA, ca037, and cadd) and examined the transcription of 26 Cp. Psittaci T3S genes namely cluster 1 (scc1, sctW, sctV, sctU), cluster 2 (sctJ, sctL, sctR, sctS, sctT, scc2, copB1, copD1), cluster 3 (sctD, sctN, ca037, sctQ, pkn5, sctC) and non-clustered genes (incA, incC, scc3, copD2, cap1, tarp, ca530, cadd). The gene expression study indicated the T3S structural protein encoding genes to be transcribed from mid-cycle (12-18 h post infection (p.i.)) on. Genes encoding effector proteins and putative T3S related proteins were expressed early (1.5 h-8 h p.i.) or late (>24 h p.i.) during the developmental cycle. We hereby provided evidence for the existence of a T3SS and possible effectors in avian Cp. Psittaci.

  • Sequencing of the Chlamydophila Psittaci ompA Gene Reveals a New Genotype, E/B, and the Need for a Rapid Discriminatory Genotyping Method
    Journal of clinical microbiology, 2005
    Co-Authors: Tom Geens, M Van Loock, Simone Magnino, Ann Desplanques, Brigitte M. Bönner, Erhard F. Kaleta, Arthur A. Andersen, Karin D. E. Everett, Daisy Vanrompay
    Abstract:

    Twenty-one avian Chlamydophila Psittaci isolates from different European countries were characterized using ompA restriction fragment length polymorphism, ompA sequencing, and major outer membrane protein serotyping. Results reveal the presence of a new genotype, E/B, in several European countries and stress the need for a discriminatory rapid genotyping method.

  • Evidence for a type III secretion system in Chlamydophila Psittaci.
    Communications in agricultural and applied biological sciences, 2003
    Co-Authors: Tom Geens, Daisy Vanrompay
    Abstract:

    In order to examine the presence of a type III secretion system in Chlamydophila Psittaci, we focused on the SctW (CopN) coding region in a locus containing four genes encoding putative products with similarity to chaperones (Sccl), secretion pore components (Cds1 and Cds2) and secreted proteins (CopN) formerly identified in the type III secretion system of other gram-negative bacteria. SctW regulates type III secretion in gram-negative bacteria. SctW expression was examined in C. Psittaci infected HeLa cells using SctW-specific polyclonal antibodies in an indirect immunofluorescence staining. SctW expression was detected 29 hours post inoculation and was absent in uninfected control cells. Immunoblotting of whole HeLa cell lysate 72 hours post inoculation with the SctW-specific polyclonal antibody also revealed the presence of SctW. Results demonstrated SctW of C. Psittaci to be expressed in at least one stage of the intracellular bacterial life cycle. The present finding may contribute to the future identification of a functional type III secretion apparatus in C. Psittaci.

M Van Loock - One of the best experts on this subject based on the ideXlab platform.

  • Exacerbation of Chlamydophila Psittaci pathogenicity in turkeys superinfected by Escherichia coli
    Veterinary research, 2006
    Co-Authors: M Van Loock, Daisy Vanrompay, Karolien Loots, Marjolein Van Heerden, Bruno Goddeeris
    Abstract:

    Both Chlamydophila Psittaci and Escherichia coli infections are highly prevalent in Belgian turkeys and therefore they both might contribute to the respiratory disease complex ob- served in turkeys. C. Psittaci can infect turkeys within the first week of age, even in the presence of maternal antibodies. However, the first C. Psittaci outbreaks occur mostly at the age of 3 to 6 weeks, the period when also E. coli infections appear on the farms. Therefore, we examined in this study the pathogenicity of an E. coli superinfection on C. Psittaci predisposed turkeys. Turkeys were in- fected with C. Psittaci, E. coli or with C. Psittaci followed by E. coli. Simulating the impact of an E. coli infection during the acute phase or the latent phase of a C. Psittaci infection, turkeys received E. coli at 1 or 5 weeks post C. Psittaci infection, respectively. E. coli superinfection during the acute phase of C. Psittaci infection increased C. Psittaci excretion and stimulated chlamydial replication in the respiratory tract resulting in exacerbated clinical disease. Interestingly, E. coli superinfection during the latent phase of C. Psittaci infection induced chlamydial replication, leading to increased C. Psittaci-specific antibody titres. In addition, chlamydial predisposition gave higher E. coli ex- cretion compared with turkeys that had only been infected with E. coli. Overall, the present study clearly demonstrates the pathogenic interplay between C. Psittaci and E. coli resulting in more severe respiratory disease. Chlamydophila Psittaci / Escherichia coli / turkeys

  • pathogenic interactions between Chlamydophila Psittaci and avian pneumovirus infections in turkeys
    Veterinary Microbiology, 2006
    Co-Authors: M Van Loock, Bruno Goddeeris, Karolien Loots, Marjolein Van Heerden, S Van De Zande, Hans Nauwynck, Daisy Vanrompay
    Abstract:

    Both Chlamydophila Psittaci and avian pneumovirus (APV) are highly prevalent in Belgian turkeys and might contribute to the respiratory disease complex observed in turkeys. Initial outbreaks of chlamydiosis occur mostly at the age of 4-8 weeks, often accompanied by an APV infection in APV non-vaccinated farms. Regardless APV vaccination, breakthroughs of APV infection from 8 weeks on do occur, a period when also a second C. Psittaci infection appears. Therefore, this study examined the pathogenicity of an APV superinfection in C. Psittaci predisposed turkeys. Turkeys were infected with C. Psittaci, APV or with C. Psittaci followed by APV. Simulating the impact of an APV infection during the acute phase or latent phase of a C. Psittaci infection, turkeys have been infected with APV at 1 and 5 weeks post C. Psittaci infection, respectively. APV infection during the acute phase of a C. Psittaci infection aggravates the severity of clinical signs, macroscopic lesions, pharyngeal APV excretion and histological tracheae lesions. In contrast, no clear interaction could be established after APV infection in latently C. Psittaci infected specific pathogen-free (SPF) turkeys. This study clearly demonstrates the exacerbating role of APV during acute C. Psittaci infection, which can play an important role in the respiratory disease complex of turkeys.

  • Exacerbation of Chlamydophila Psittaci pathogenicity in turkeys superinfected by Escherichia coli
    Veterinary Research, 2006
    Co-Authors: M Van Loock, Daisy Vanrompay, Karolien Loots, Marjolein Van Heerden, Bruno Goddeeris
    Abstract:

    Both Chlamydophila Psittaci and Escherichia coli infections are highly prevalent in Belgian turkeys and therefore they both might contribute to the respiratory disease complex observed in turkeys. C. Psittaci can infect turkeys within the first week of age, even in the presence of maternal antibodies. However, the first C. Psittaci outbreaks occur mostly at the age of 3 to 6 weeks, the period when also E. coli infections appear on the farms. Therefore, we examined in this study the pathogenicity of an E. coli superinfection on C. Psittaci predisposed turkeys. Turkeys were infected with C. Psittaci, E. coli or with C. Psittaci followed by E. coli. Simulating the impact of an E. coli infection during the acute phase or the latent phase of a C. Psittaci infection, turkeys received E. coli at 1 or 5 weeks post C. Psittaci infection, respectively. E. coli superinfection during the acute phase of C. Psittaci infection increased C. Psittaci excretion and stimulated chlamydial replication in the respiratory tract resulting in exacerbated clinical disease. Interestingly, E. coli superinfection during the latent phase of C. Psittaci infection induced chlamydial replication, leading to increased C. Psittaci-specific antibody titres. In addition, chlamydial predisposition gave higher E. coli excretion compared with turkeys that had only been infected with E. coli. Overall, the present study clearly demonstrates the pathogenic interplay between C. Psittaci and E. coli resulting in more severe respiratory disease.

  • Use of a nested PCR-enzyme immunoassay with an internal control to detect Chlamydophila Psittaci in turkeys.
    BMC infectious diseases, 2005
    Co-Authors: M Van Loock, Bruno Goddeeris, Guido Volckaert, Kristel Verminnen, Trudy O Messmer, Daisy Vanrompay
    Abstract:

    Background Laboratory diagnosis of Chlamydophila Psittaci, an important turkey respiratory pathogen, is difficult. To facilitate the diagnosis, a nested PCR-enzyme immunoassay (PCR-EIA) was developed to detect the Cp. Psittaci outer membrane protein A (ompA) gene in pharyngeal swabs.

  • CpG motifs as adjuvant in DNA vaccination against Chlamydophila Psittaci in turkeys.
    Vaccine, 2005
    Co-Authors: Karolien Loots, Daisy Vanrompay, M Van Loock, Bruno Goddeeris
    Abstract:

    Plasmid DNA (pcDNA1::MOMP) expressing the major outer membrane protein (MOMP) of an avian Chlamydophila Psittaci serovar D strain and recombinant MOMP (rMOMP) with or without the immunomodulating CpG oligonucleotides (CpG ON) were tested for their ability to elicit an immune response and to induce protection in turkeys against homologous challenge. Two CpG ON were chosen for in vivo application based on their in vitro capacity to stimulate the production of nitric oxide (NO) in chicken macrophages and their in vitro capacity to induce turkey lymphocyte proliferation. Priming and boosting of turkeys with pcDNA1::MOMP was able to prevent severe clinical signs and bacterial replication in a turkey model of C. Psittaci infection. rMOMP boosting induced high antibody titers, but these did not correlate with the level of protection. Although the CpG ON induced a significant in vitro response, the presence of the CpG ON as an adjuvant generated no significant effect on the immune response or on the protective capacity of the tested vaccination methods.