References of "Thomas, Anne"
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See detailDetection of disease resistance and susceptibility alleles in pigs using oligonucleotide microarray hybridization
Pastoret, Soumya; Ameels, Hélène; Bossiroy, Frédérique et al

in Journal of Veterinary Diagnostic Investigation (2012), 24(3), 479-488

A multiplex DNA microarray chip aimed at the identification of allelic polymorphisms was developed for simultaneous detection of swine disease resistance genes underlying malignant hyperthermia (RYR ... [more ▼]

A multiplex DNA microarray chip aimed at the identification of allelic polymorphisms was developed for simultaneous detection of swine disease resistance genes underlying malignant hyperthermia (RYR ), postweaning diarrhea, edema disease (FUT1), neonatal diarrhea (MUC4), and influenza (MX1). The on-chip detection was performed with fragmented polymerase chain reaction (PCR)-amplified products. Particular emphasis was placed on the reduction of the number of PCR reactions required. The targets were biotin labeled during the PCR reaction, and the arrays were detected using a colorimetric methodology. Target recognition was provided by specific capture probes designed for each susceptible or resistant allelic variant. Sequencing was chosen as the golden standard to assess chip’s accuracy. All genotypes retrieved from the microarray (476) fitted with sequencing data in spite of the fact that each pig was heterozygote for at least 1 target gene. [less ▲]

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See detailDifferential anti-influenza activity among allelic variants at the Sus scrofa Mx1 locus
Palm, Mélanie; Leroy, Michael; Thomas, Anne et al

in Journal of Interferon & Cytokine Research (2007), 27(2), 147-155

A promising way to oppose infectious challenges would be to improve the resistance of the target species through genetic selection. Theoretically, a candidate gene is available against influenza viruses ... [more ▼]

A promising way to oppose infectious challenges would be to improve the resistance of the target species through genetic selection. Theoretically, a candidate gene is available against influenza viruses since a resistance trait was fortuitously discovered in the A2G mouse strain. This trait was demonstrated to be correlated with the expression of a specific isoform of the type I interferon (IFN)-dependent protein MX, an isoform coded by a specific allele at the mouse Mx1 locus. Two allelic polymorphisms were described recently in the Sus scrofa homologous gene. In this study, the frequencies and distribution of both alleles were evaluated among European domestic pig and wild boar populations by PCR-RFLP, and the anti-influenza activity conferred by both MX1 isoforms was evaluated in vitro using transfection of Vero cells followed by flow cytometric determination of the fraction of influenza virus-infected cells among MX-producing and MX-nonproducing cell populations. A significant difference in the anti-influenza activity brought by the two MX1 isoforms was demonstrated, which suggests that a significant improvement of innate resistance of pigs by genetic selection might be feasible provided the differences found here in vitro are epidemiologically relevant in vivo. [less ▲]

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See detailGenomic structure, promoter analysis and expression of the porcine (Sus scrofa) TLR4 gene.
Thomas, Anne; Broers, Aurore ULg; Vandegaart, Hélène ULg et al

in Molecular Immunology (2006), 43(6), 653-659

Toll-like receptor 4 (TLR4) is essential for initiating the innate response to lipopolysaccharide (LPS) from Gram-negative bacteria by acting as a signal-transducing receptor. As the pig industry faces a ... [more ▼]

Toll-like receptor 4 (TLR4) is essential for initiating the innate response to lipopolysaccharide (LPS) from Gram-negative bacteria by acting as a signal-transducing receptor. As the pig industry faces a unique array of related pathogens, it is anticipated that the genotype of swine TLR4 could be of crucial importance in future strategies aimed at improving genetic resistance to infectious diseases. In order to help in investigating TLR4 as a candidate disease-resistance gene in pigs, we established its genomic structure and produced sufficient flanking intronic sequences to enable simple PCR amplification of the coding portions of the gene. Expression in different porcine tissues was studied and showed splicing variations in mRNA sequences. The cDNA sequence for poTLR4 contains an open reading frame of 2526bp that codes for 841 aa, 98 and 568bp in the 5'- and 3'-UTRs, respectively. Overall, the general organization of porcine, human, murine, and avian TLR4 genes is quite similar: three exons with the third one very long. A high level of conservation of the size and the sequence, especially for the two last exons and particularly in the sequence corresponding to the LRRs and TIR domain, is observed between species. The important antimicrobial properties of these proteins may account for a conservative selection pressure on these TLR4 coding sequences. Several putative binding sites described in the human and murine promoter of TLR4 genes have been identified in the 5'-flanking region of poTLR4. Conversely, this region lacks a TATA box, consensus initiator sequences, or GC-rich regions. The basic sequence data gathered will allow the establishment of an inventory of naturally occurring variation in porcine TLR4, so that alleles can be tested for disease association studies. [less ▲]

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See detailGenomic structure, promoter analysis, and expression of the porcine (Sus scrofa) Mx1 gene
Thomas, Anne; Palm, Mélanie; Broers, Aurore ULg et al

in Immunogenetics (2006), 58

Allelic polymorphisms at the mouse Mx1 locus affect the probability of survival after experimental influenzal disease, raising the possibility that marker-assisted selection using the homologous locus ... [more ▼]

Allelic polymorphisms at the mouse Mx1 locus affect the probability of survival after experimental influenzal disease, raising the possibility that marker-assisted selection using the homologous locus could improve the innate resistance of pigs to natural influenza infections. Several issues need to be resolved before efficient large scale screening of the allelic polymorphism at the porcine (Sus scrofa) Mx1 locus can be implemented. First, the Mx1 genomic structure has to be established and sufficient flanking intronic sequences have to be gathered to enable simple PCR amplification of the coding portions of the gene. Then, a basic knowledge of the promoter region needs to be obtained as an allelic variation there can significantly alter absolute levels and/or tissue-specificity of MX protein expression. The results gathered here show that the porcine Mx1 gene and promoter share the major structural and functional characteristics displayed by their homologs described in cattle, mouse, chicken, and man. The crucial function of the proximal interferon-sensitive response elements motif for gene expression is also demonstrated. The sequence data compiled here will allow an extensive analysis of the polymorphisms present among the widest spectrum possible of porcine breeds with the aim to identify an Mx1 allele providing antiviral resistance. [less ▲]

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See detailSuppression of pattern recognition receptor TLR4 sensing does not alter lung responses to pneumovirus infection
Faisca, Pedro; Bui Tran Anh, Dao; Thomas, Anne et al

in Microbes & Infection (2006), 8

Toll-like receptors (TLR) are an important component in the innate immune response to a wide variety of pathogens. Recently, a series of studies has addressed the hypothesis that TLR4 also participates in ... [more ▼]

Toll-like receptors (TLR) are an important component in the innate immune response to a wide variety of pathogens. Recently, a series of studies has addressed the hypothesis that TLR4 also participates in the host innate response against respiratory syncytial virus (RSV), the leading cause of lower respiratory tract infections in infants and young children. In most of the studies available, RSV, which is not a natural pathogen of mice, has been systematically used in mouse models of human bronchiolitis, with conflicting results. Pneumonia virus of mice (PVM), a member of the pneumovirus genus, shares many similarities with RSV. The serological and structural relationships that exist between them suggest that the immune response to these viruses may be similar in their respective natural hosts. To determine the role of TLR4 in host defense against PVM, TLR4-competent and TLR4-deficient mice were intranasally infected with PVM. Variation of body weight, pulmonary function values, histopathology, and pulmonary viral loads were analyzed. None of the investigated clinical, functional, histological and virological parameters was different between strains, which demonstrates that the sensitivity of the mouse to its natural pneumovirus infection is independent of the presence or absence of TLR4 sensing. [less ▲]

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See detailMycoplasma bovis shares insertion sequences with Mycoplasma agalactiae and Mycoplasma mycoides subsp mycoides SC: Evolutionary and developmental aspects
Thomas, Anne; Linden, Annick ULg; Mainil, Jacques ULg et al

in FEMS Microbiology Letters (2005), 245(2), 249-255

Three new insertion elements, IS Mbov1, ISMbov2 and ISMbov3, which are closely related to ISMag1 (Mycoplasma agalactiae), ISMmy1 and IS1634 (both Mycoplasma in mycoides subsp. in mycoides SC ... [more ▼]

Three new insertion elements, IS Mbov1, ISMbov2 and ISMbov3, which are closely related to ISMag1 (Mycoplasma agalactiae), ISMmy1 and IS1634 (both Mycoplasma in mycoides subsp. in mycoides SC), respectively, have been discovered in Mycoplasma bovis, an important pathogen of cattle. Southern blotting showed that the genome of M. bovis harbours 6-12 copies of ISMbov1, 11-15 copies of ISMbov2 and 4-10 copies of ISMbov3, depending on the strain. A fourth insertion element, the IS30-like element, is present in 4-8 copies. This high number of IS elements in AI bovis, which represent a substantial part of its genome, and their relatedness with IS elements of both M. agalactiae and M. mycoides subsp. mycoides SC suggest the occurrence of two evolutionary events: (i) a divergent evolution into ill. agalactiae and M. bovis upon infection of different hosts; (ii) a horizontal transfer of IS elements during co-infection with M. mycoides subsp. mycoides SC and Ad. bovis of a same bovine host. (c) 2005 Federation of European Microbiological Societies. Published by Elsevier B.V. All rights reserved. [less ▲]

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See detailIdentification by two-dimensional electrophoresis of a new adhesin expressed by a low-passaged strain of Mycoplasma bovis
Thomas, Anne; Leprince, Pierre ULg; Dizier, Isabelle ULg et al

in Research in Microbiology (2005), 156(5-6, Jun-Jul), 713-718

A significant decrease in adherence rates of Mycoplasma bovis to bovine bronchial epithelial (BBE) cells has been observed after passage of the organism in artificial medium. Analysis of the proteins ... [more ▼]

A significant decrease in adherence rates of Mycoplasma bovis to bovine bronchial epithelial (BBE) cells has been observed after passage of the organism in artificial medium. Analysis of the proteins expressed by M. bovis isolate 2610 by two-dimensional (2-D) electrophoresis demonstrated differences between the cells harvested after the 7th and 116th passage. Three silver-stained prominent spots observed in 2-D electrophoretic separation of protein extracts of the lower-passaged cells were considerably less strongly expressed in the sample from higher-passaged cells. These spots had a molecular mass of approximately 24 kDa and an isoelectric point of about 5. The mass spectrometry analysis of these trypsin-sensitive proteins led to their identification as a unique new member of the Vsps family of membrane-associated proteins. Serum from a mouse immunized with these proteins significantly reduced adherence of M. bovis to BBE cells. This result underlines the function of this new Vsp in adherence of M. bovis to host cells. (c) 2005 Elsevier SAS. All rights reserved. [less ▲]

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See detailThe p40* adhesin pseudogene of Mycoplasma bovis
Thomas, Anne; Linden, Annick ULg; Mainil, Jacques ULg et al

in Veterinary Microbiology (2004), 104(3-4), 213-217

An analogue of the adhesin gene p40 of Mycoplasma agalactiae was found in Mycoplasma bovis. Nucleotide sequence analysis of the p40* gene in M. bovis revealed the presence of a large deletion involving a ... [more ▼]

An analogue of the adhesin gene p40 of Mycoplasma agalactiae was found in Mycoplasma bovis. Nucleotide sequence analysis of the p40* gene in M. bovis revealed the presence of a large deletion involving a frameshift that causes premature truncation of the translated protein, indicating that p40* exists as a pseudogene in M. bovis. (C) 2004 Elsevier B.V. All rights reserved. [less ▲]

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See detailConservation of the uvrC gene sequence in Mycoplasma bovis and its use in routine PCR diagnosis
Thomas, Anne; Dizier, Isabelle ULg; Linden, Annick ULg et al

in Veterinary Journal (2004), 168(1), 100-102

Mycoplasma bovis is a major cause of pneumonia and arthritis in calves, and of mastitis and genital infections in adult cows. It is responsible for high economic loss in feedlot cattle although it is ... [more ▼]

Mycoplasma bovis is a major cause of pneumonia and arthritis in calves, and of mastitis and genital infections in adult cows. It is responsible for high economic loss in feedlot cattle although it is often underestimated and is widely spread within the bovine population in enzootically infected areas. [less ▲]

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See detailAntibiotic susceptibilities of recent isolates of Mycoplasma bovis in Belgium
Thomas, Anne; Nicolas, C.; Dizier, Isabelle ULg et al

in Veterinary Record (2003), 153(14), 428-431

The susceptibilities of 40 recent Belgian field isolates of Mycoplasma bovis to 10 antimicrobial agents were assessed. Tiamulin was the most active antimicrobial agent against M bovis, with an initial ... [more ▼]

The susceptibilities of 40 recent Belgian field isolates of Mycoplasma bovis to 10 antimicrobial agents were assessed. Tiamulin was the most active antimicrobial agent against M bovis, with an initial inhibitory concentration (IIC50) of 0.06 microg/ml, but it is not licensed for the treatment of cattle. All three fluoroquinolones tested (danofloxacin, enrofloxacin and marbofloxacin) were effective against strains of M bovis, and had a minimum mycoplasmacidal concentration (MMC50) less than or equal to 1 microg/ml. Gentamicin was poorly effective, having an IIC50 of 8 microg/ml. Many strains of M bovis were resistant to tylosin, spectinomycin, lincomycin, tetracycline and oxytetracycline. [less ▲]

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See detailAdherence of Mycoplasma bovis to bovine bronchial epithelial cells
Thomas, Anne; Sachse, K.; Farnir, Frédéric ULg et al

in Microbial Pathogenesis (2003), 34(3), 141-148

Mycoplasma bovis is responsible for considerable economic losses in cattle due to pneumonia, arthritis and mastitis. As the agent was shown to be capable of adhering to neutrophils and embryonic bovine ... [more ▼]

Mycoplasma bovis is responsible for considerable economic losses in cattle due to pneumonia, arthritis and mastitis. As the agent was shown to be capable of adhering to neutrophils and embryonic bovine lung (EBL) cells and invading the respiratory epithelium it is highly desirable to improve our understanding of cytadherence processes. Although several surface proteins likely to be directly involved in this initial stage of interaction between pathogen and host cells have been identified, these findings mainly referred to type strain PG45 adhering to the continuous EBL cell line. The present study provides new and complementary data about cytadherence of M. bovis based on adherence of various radiolabeled strains to a primary culture of bovine bronchial epithelial (BBE) cells using a standardized adherence assay. M. bovis was shown to adhere specifically to the primary culture of BBE cells. Inhibition of adherence was observed upon addition of monoclonal antibodies (MAbs), trypsin treatment of mycoplasmas, and competition with non-radiolabeled mycoplasma cells. Interestingly, three MAbs against proteins involved in adherence to EBL cells failed to inhibit significantly the adherence to BBE cells. On the other hand, significant reduction of adherence rates by MAbs 2A8 and 9F1 directed against epitopes of variable surface lipoproteins VspC and VspF, respectively, demonstrated the involvement of these proteins in adherence of M. bovis to primary culture of BBE cells. (C) 2003 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailMycoplasma bovis dans le complexe respiratoire bovin et propriétés de cyto-adhésion in vitro
Thomas, Anne; Dizier, Isabelle ULg; Sachse, K. et al

in Annales de Médecine Vétérinaire (2003), 147(4, AUG-SEP), 267-272

Mycoplasmas frequently infect cattle, causing especially respiratory diseases. Mycoplasma bovis is the most important pathogenic species in countries free of bovine contagious pleuropneumonia. This ... [more ▼]

Mycoplasmas frequently infect cattle, causing especially respiratory diseases. Mycoplasma bovis is the most important pathogenic species in countries free of bovine contagious pleuropneumonia. This species was frequently isolated in Belgium from cattle with respiratory disease. Furthermore, associations were often observed with pasteurellas and bovine respiratory syncytial virus. Of these M. bovis isolates, many were resistant to several antimicrobial agents which are used in cattle practice, except to fluoroquinolones. Inasmuch the high frequency of M. bovis isolation and antibiotic resistances, it is very important to understand the pathogenicity of this bacteria in order to optimize prophylactic tools. Therefore, the study of the cytadherence of M. bovis is essential since it represents the first step of the bacterial infection. According to our experimental results, PG45 is not representative of field isolates because of its low adherence rates to various cell lines. This could be explained by the high number of subcultures of this pathogenic strain underwent since its first isolation, which sharply contrasts with other isolates. M. bovis adheres specifically to bovine bronchial epithelial cells in primary culture. Proteins such as variable surface proteins C and F are involved in this step as observed by decreased adherence rates after trypsinization of mycoplasma cells or addition of monoclonal antibodies. [less ▲]

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See detailMycoplasma bovis : synthèse des connaissances actuelles
Thomas, Anne; Mainil, Jacques ULg; Linden, Annick ULg

in Annales de Médecine Vétérinaire (2003), 147(1, FEB-MAR), 23-39

Mycoplasmas frequently infect cattle. Amongst them, M. Bovis is the most pathogenic species in countries free from contagious bovine pleuropneumonia because it is responsible for bronchopneumonia ... [more ▼]

Mycoplasmas frequently infect cattle. Amongst them, M. Bovis is the most pathogenic species in countries free from contagious bovine pleuropneumonia because it is responsible for bronchopneumonia, arthritis and mastitis, and is thus associated with strong economic losses. Several studies have shown the frequency of M. bovis in Europe and the spread of antibiotic-resistant strains. Considering the absence of vaccine in Europe, it is essential to understand this bacteria in order to control the infection in cattle. In this context, this paper aims at summarizing the current knowledge about M. bovis. [less ▲]

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See detailAdherence to various host cell lines of Mycoplasma bovis strains differing in pathogenic and cultural features
Thomas, Anne; Sachse, Konrad; Dizier, Isabelle ULg et al

in Veterinary Microbiology (2003), 91(2-3), 101-113

Mycoplasma bovis is known to be responsible for pneumonia and arthritis in calves, as well as mastitis in dairy cows. Despite clear evidence of its pathogenic potential, little is known about mechanisms ... [more ▼]

Mycoplasma bovis is known to be responsible for pneumonia and arthritis in calves, as well as mastitis in dairy cows. Despite clear evidence of its pathogenic potential, little is known about mechanisms of cytadherence and the molecular factors involved. The purpose of this work was to compare adherence rates of M. bovis field strains to different host cell lines and study the effects of cloning and sub-culturing M. bovis strains on their adherence properties. Eighteen metabolically labeled M. bovis strains isolated from different pathological backgrounds were examined in adherence trials using four different host cell lines, i.e. embryonic bovine lung (EBL), embryonic bovine trachea (EBTr), Madin Darby bovine kidney (MDBK) and rabbit kidney (RK) cells. Although large interstrain variations in adherence rates (3.4-19.1%) were measured they could not be correlated to the pathological background (pneumonia, arthritis or mastitis). Adherence rates to the fibroblast cell line (EBTr) were significantly lower than those to the three epithelial cell lines (EBL, MDBK and RK). The only non-pathogenic strain (221/89) exhibited lower adherence rates than three isolates from clinical mastitis. Interestingly, adherence rates were significantly reduced after in vitro passaging. In contrast, no effect of single cloning of strains on adherence was observed. There was no general correlation between expression of variable surface proteins (Vsps) as monitored by immunoblotting and adherence rates, although alterations in Vsp expression profiles were seen as a consequence of passaging. As there is probably a large number of adhesins, variable and non-variable, on the surface of M. bovis cells the issue is very complex, and the most active components have yet to be identified. [less ▲]

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See detailIsolation of Mycoplasma species from the lower respiratory tract of healthy cattle and cattle with respiratory disease in Belgium
Thomas, Anne; Ball, H.; Dizier, Isabelle ULg et al

in Veterinary Record (2002), 151(16), 472-476

Between 1997 and 2000, a total of 150 healthy cattle and 238 animals with respiratory disease were examined for six Mycoplasma species. Attempts were made to detect Mycoplasma canis, Mycoplasma dispar and ... [more ▼]

Between 1997 and 2000, a total of 150 healthy cattle and 238 animals with respiratory disease were examined for six Mycoplasma species. Attempts were made to detect Mycoplasma canis, Mycoplasma dispar and Ureaplasma diversum in calves with recurrent disease, and all three of these species were identified in calves with recurrent disease and in healthy lungs. In healthy calves, 84 per cent of bronchoalveolar lavage fluids were mycoplasma free; when cultures were positive, Mycoplasma bovirhinis was the only species isolated. Mycoplasmas were isolated from 78 per cent of animals suffering recurrent respiratory disease and from 65 per cent of acute respiratory cases. Mycoplasma bovis was isolated from bronchoalveolar lavages from 35 per cent of calves suffering recurrent respiratory disease, and from 50 per cent of acute cases, and from 20 per cent of pneumonic cases examined postmortem. M bovis was associated with other Mycoplasma species in 44 per cent of cases. M dispar was also isolated from 45.5 per cent of calves suffering recurrent respiratory disease, often in association with M bovis. M canis was identified for the first time in diseased Belgian cattle. Other mycoplasmas, including Mycoplasma arginini, Mycoplasma alkalescens and U diversum, were isolated less frequently. Associations between mycoplasmas and other pathogens were often observed. Among lungs infected with Pasteurella and/or Mannheimia species, more than 50 per cent were mixed infections with M bovis. [less ▲]

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See detailComparison of sampling procedures for isolating pulmonary mycoplasmas in cattle
Thomas, Anne; Dizier, Isabelle ULg; Trolin, A. et al

in Veterinary Research Communications (2002), 26(5), 333-339

Three sampling procedures were compared to determine the optimal technique for isolating mycoplasmas in cattle with respiratory diseases. The prevalence of mycoplasmas isolated from these animals is also ... [more ▼]

Three sampling procedures were compared to determine the optimal technique for isolating mycoplasmas in cattle with respiratory diseases. The prevalence of mycoplasmas isolated from these animals is also reported. In the first group, bronchoalveolar lavage (BAL) and nasal swab cultures were compared with the corresponding lung cultures from cattle necropsied for fatal respiratory diseases (n = 20). In a second group, nasal swabs were compared with corresponding BAL cultures in living animals with recurrent respiratory pathologies (n = 49). There was complete agreement between the paired BAL and lung cultures. In contrast, nasal cultures were not representative of the mycoplasmas present in the lower respiratory airways. The relative sensitivity and specificity of the nasal swab technique compared to BAL in living animals confirmed that the nasal swab cultures were not predictive of lower respiratory airway pathogens, such as Mycoplasma bovis. BAL is considered to be the best method for isolating M. bovis in cattle with respiratory diseases as it combines reliability and feasibility under field sampling conditions. In the present study, Mycoplasma dispar (43%) and M. bovis (29%) were mainly isolated in mixed infections. This confirms the need to search for mycoplasmas in routine examinations and to take them into account in therapeutic strategies for respiratory diseases in cattle. [less ▲]

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