Dissertations / Theses: 'Catarrhalis'

1

Enright, Mark Charles. "Molecular characterization of Moraxella catarrhalis." Thesis, University of Aberdeen, 1994. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=158242.

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Moraxella catarrhalis is a gram-negative diplococcus which until recently was thought to be a harmless commensal. Increasing awareness has established the pathogenic nature of this organism and it is now recognised as a major cause of otitis media in children, exacerbations of chronic bronchitis in elderly patients and an occasional cause of invasive disease. M. catarrhalis is spread nosocomially especially in respiratory wards containing elderly patients. This study evaluated four methods for typing nosocomially spread isolates:- immunoblotting with normal human serum (NHS), and three DNA fingerprinting methods. The most discriminatory method found was restriction endonuclease analysis (REA) using Taq I, although immunoblotting with NHS and pulsed-field gel electrophoresis (PFGE) using Sma I sub-divided isolates grouped together by the other methods. PFGE using Not I only confirmed groupings made by other methods. A study of M. catarrhalis and phenotypically similar organisms was performed using comparisons of partial 16S rDNA sequence. 16S rDNA of M. catarrhalis strains from disparate geographical locations was found to be extremely conserved M. catarrhalis 16S rDNA was very similar to that of other Moraxella species whilst Moraxella species were found to be generally distinct from the Neisseria and Kingella species studied. These results confirm M. catarrhalis as a genuine member of the Moraxellae.

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2

Gill, Lyndell R. "Moraxella (Branhamella) Catarrhalis: A Molecular Epidemiology Study." Digital Commons @ East Tennessee State University, 1995. https://dc.etsu.edu/etd/2684.

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Moraxella (Branhamella) catarrhalis is the third-most-frequently isolated microorganism associated with acute exacerbations of chronic bronchitis in patients during their stay at the Mountain Home VA Medical Center (MHVAMC). In order to develop a practical, epidemiologically-meaningful typing method for M. (B.) catarrhalis, we tested two methods based on analysis of chromosomal DNA for typeability, reproducibility, and ability to differentiate between unrelated strains (discriminatory power, D). M. (B.) catarrhalis isolants from MHVAMC from 7/1/87-6/30/88 were grown overnight in broth and embedded in agarose. DNA was isolated by standard methods. The DNA was subjected to: (1) restriction endonuclease digestion (with either Bgl II or Pme I) followed by pulsed-field gel electrophoresis (PFGE) and (2) restriction endonuclease digestion (with Hae III), followed by horizontal gel electrophoresis, Southern transfer and hybridization with a M. (B.) catarrhalis-specific DNA probe (M46). Reliable and reproducible patterns were produced from 144 of 159 isolants (91%) using Hae III, 155 of 159 (97%) using Pme I, and all isolants using Bgl II. Three clusters of isolants, Groups A (n = 18), B (n = 18), and C (n = 12) were detected. Within each group, isolants were identical by all typing methods tested. Chart review revealed no apparent epidemiologic link for Group A, while in Group B, 16 of 18 patients were housed on two wards, and in Group C, all cases occurred within two months, suggesting epidemiologic links within Groups B and C. Comparisons of results from isolants from various wards and isolants from outpatients were used to determine D of each method. Digestion with Pme I followed by PFGE was the most discriminating technique (D = 0.978) followed by Bgl II with PFGE (D = 0.962), then M46 probe hybridization (D = 0.929). The restriction endonucleases Pme I and Bgl II were highly discriminating and useful in the epidemiologic typing of M. (B.) catarrhalis. While useful, the M46 probe following Hae III digestion was not as discriminating.

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3

Bullard, Brian. "Characterization of the Moraxella catarrhalis Hag Adhesin." University of Toledo Health Science Campus / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=mco1195596894.

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4

Stawska, Agnieszka A. "Purification of Aspartate Transcarbamoylase from Moraxella (Branhamella) catarrhalis." Thesis, University of North Texas, 2001. https://digital.library.unt.edu/ark:/67531/metadc2864/.

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The enzyme, aspartate transcarbamoylase (ATCase) from Moraxella (Branhamella) catarrhalis, has been purified. The holoenzyme has a molecular mass of approximately 510kDa, harbors predominantly positive charges and is hydrophobic in nature. The holoenzyme possesses two subunits, a smaller one of 40 kDa and a larger one of 45 kDa. A third polypeptide has been found to contribute to the overall enzymatic activity, having an approximate mass of 55 kDa. The ATCase purification included the generation of cell-free extract, streptomycin sulfate cut, 60 °C heat step, ammonium sulfate cut, dialysis and ion, gel-filtration and hydrophobic interaction chromatography. The enzyme's performance throughout purification steps was analyzed on activity and SDS-PAGE gradient gels. Its enzymatic, specific activities, yield and fold purification, were also determined.

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5

Attia, Ahmed Sherif. "The USPA2 protein and serum resistance of Moraxella Catarrhalis." Access to abstract only; dissertation is embargoed until after 5/15/2007, 2006. http://www4.utsouthwestern.edu/library/ETD/etdDetails.cfm?etdID=145.

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6

Fowler, Michael A. (Michael Allen) 1961. "Characterization of Aspartate Transcarbamoylase and Dihydroorotase in Moraxella Catarrhalis." Thesis, University of North Texas, 1998. https://digital.library.unt.edu/ark:/67531/metadc277709/.

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Bacterial aspartate transcarbamoylases (ATCase's) are divided into three classes that correspond to taxonomic relationships within the bacteria. The opportunistic pathogen Moraxeila catarrhalis has undergone several reclassifications based on traditional microbiological criteria. The previously uncharacterized ATCase from M. catarrhalis was purified to homogeneity and its chemical properties characterized. The ATCase from M. catarrhalis is a class C ATCase with an apparent molecular mass of 480-520 kDa. The M. catarrhalis ATCase is a dodecomer composed of six 35 kDa polypeptides and six 45 kDa polypeptides. The enzyme has an unusually high pH optimum of greater than pH 10. The enzyme exhibited hyperbolic kinetic with a Km for aspartate of 2 mM. A single, separate 78 kDa dihydroorotase from M. catarrhalis was identified and it was not associated with ATCase. These data support the reclassification of M. catarrhalis out of the Neisseriaceae family.

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7

Bowman, Melissa Lynne. "Biochemical characterization of Moraxella catarrhalis strains associated with Otitis media." Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/25397.

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8

Easton, Donna Meredith, and n/a. "Functional and Antigenic Characterisation of the Moraxella catarrhalis protein M35." University of Canberra. n/a, 2008. http://erl.canberra.edu.au./public/adt-AUC20081217.083105.

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This thesis reports the characterisation of a novel outer membrane protein (OMP) from M. catarrhalis, designated M35, with a molecular mass of 36.1 kDa. This protein is structurally homologous to classic Gram-negative porins, such as OMP C from E. coli and OMP K36 from K. pneumoniae, with a predicted structure of 8 surface loops connecting 16 antiparallel -sheets. Comparison of the DNA sequences of the M35 genes from 18 diverse clinical isolates showed that the gene was highly conserved (99.6-100 % of nucleotides) with only one isolate (ID78LN266) having base variations that resulted in amino acid substitutions. A single amino acid mutation in the 3rd external loop of M35 in isolate ID78LN266 significantly affected antibody recognition, indicating that loop 3 contains an immunodominant B-cell epitope. The reduction in antibody-binding to M35 from ID78LN266 was similar to that caused by complete removal of loop 3. Since loop 3 folds into the porin channel in the classic structure, the antibody specificity to loop 3 was hypothesised to be a potential mechanism for evasion of host immune responses targeted to M35, potentially explaining the high degree of conservation across isolates. A series of recombinant proteins were constructed to analyse the binding to M35 of antibodies specificity for loop 3 or the remainder of the protein. It was found that loop 3- specific antibodies were not able to bind to M35 on the surface of M. catarrhalis and that this corresponds both with a lack of ability to enhance opsonophagocytosis in vitro and bacterial clearance in vivo. Additionally, antibodies raised against a version of M35 lacking loop 3 and M35 from the variant isolate ID78LN266 were both no less effective than the full consensus M35 by both these measures. It therefore appears that while the majority of antibodies raised against M35 are specific for loop 3 these antibodies do not mediate anti-M. catarrhalis actions. Two deletion mutant strains of M. catarrhalis that do not contain the outer membrane protein M35 were created by insertional inactivation of the M35 gene. Growth comparisons between these mutant strains and their wildtype parent strains initially led to the hypothesis that M35 is necessary for efficient glutamic acid uptake by M. catarrhalis, however this hypothesis was later shown to be incorrect. Efficient uptake of glutamic acid seemed to be mediated by a novel 40 kDa protein that was up-regulated in the deletion mutant strains, presumably to compensate for the lack of M35. M35 was also found to be essential for in vivo survival of M. catarrhalis in the nasal cavities of mice, indicating that it is an essential functional protein for colonisation of the mucosal surface.

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9

Jonatat, Carola [Verfasser]. "Die Aktivierung des humanen Bronchialepithels durch Moraxella catarrhalis / Carola Jonatat." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2009. http://d-nb.info/1023464616/34.

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10

Yeo, Siew-Fah. "Epidemiology and antimicrobial resistance of Haemophilus influenzae and Moraxella catarrhalis." Thesis, Queen Mary, University of London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309743.

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11

Nguyen, Kim Thuy. "Construction of a Physical Map of Moraxella (Branhamella) catarrhalis Strain ATCC25238." Thesis, University of North Texas, 1999. https://digital.library.unt.edu/ark:/67531/metadc279104/.

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In order to gain a better understanding of this microorganismand its role in human pathogenesis, a physical map of Moraxella catarrhalis type strain ATCC25238 was constructed using pulsed field gel electrophoresis (PFGE) in combination with Southern hybridization techniques. Restriction endonucleases Not I, Rsr II, and Sma I were used to digest the chromosomal DNA. An overlapping circular map was generated by cross-hybridization of isolated radiolabeled fragments of Moraxella catarrhalis genomic DNA to dried PFGE gels. The number and location of the 16S and 23S ribosomal RNA genes were determined by digestion with l-Ceul enzyme and by Southern hybridization. Virulence-associated genes, the gene for β-lactamase, and housekeeping genes were also placed onto the physical map.

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12

Vigelahn, Manuel [Verfasser]. "Molekulare Mechanismen der Moraxella catarrhalis induzierten Apoptose pulmonaler Epithelzellen / Manuel Vigelahn." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2015. http://d-nb.info/1079524452/34.

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13

Campbell, Sara J. "Mechanisms of Moraxella catarrhalis Induced Immune Signaling in the Pulmonary Epithelium." University of Toledo Health Science Campus / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=mco1268141520.

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14

Akimana, Christine. "Structural and Functional Analysis of Moraxella catarrhalis Adhesins MCAP and OMPCD." University of Toledo Health Science Campus / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=mco1180025995.

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15

Slevogt, Hortense Gisela [Verfasser]. "Molekulare Mechanismen der Interaktion von Moraxella catarrhalis mit pulmonalen Epithelzellen / Hortense Gisela Slevogt." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2009. http://d-nb.info/1023783436/34.

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16

Chen, Miao. "Moraxella catarrhalis-induced innate immune responses in human pulmonary epithelial cells and monocytes." Toledo, Ohio : University of Toledo, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=mco1260375737.

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Dissertation (Ph.D.)--University of Toledo, 2009.
["In partial fulfillment of the requirements for the degree of Doctor of Philosophy in Biomedical Sciences."] Title from title page of PDF document. Bibliography: p. 80-112.

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17

Heinrich, Annina. "Die Bedeutung von CEACAM3 für die Moraxella catarrhalis induzierte Aktivierung von humanen Granulozyten." Doctoral thesis, Humboldt-Universität zu Berlin, 2018. http://dx.doi.org/10.18452/18831.

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Die COPD (chronic obstructive pulmonary disease) ist eine weltweit vorkommende, chronisch obstruktive Erkrankung der Lunge. Sie gilt als vierthäufigste Todesursache weltweit, wobei ein Viertel der akuten bakteriellen Exazerbationen auf eine Infektion mit Moraxella catharralis zurückzuführen sind. Sowohl das akute, als auch das chronische Entzündungsbild der COPD wird überwiegend durch neutrophile Granulozyten in den Atemwegen bestimmt, die neben antimikrobiellen Effektorfunktionen durch Freisetzung von Zytokinen auch die Entzündungsreaktion bzw. Immunantwort regulieren können. In dieser Arbeit wurde untersucht inwiefern die Interaktion von M.catarrhalis mit dem humanen Granuloyzten-spezifischen Rezeptor carcinoembryonic antigen-related cell adhesion molecule (CEACAM)3 zu einer Aktivierung der neutrophilen Granuloyzten sowie zu einer NF-kappaB-abhängigen Chemokinproduktion führt. Primäre Granulozyten gesunder Spender sowie NB4 Zellen wurden mit M.catarrhalis in Anwesenheit verschiedener Inhibitoren, siRNA oder CEACAM-blockender Antikörper infiziert und anschließend die Chemokinsekretion mittels ELISA bestimmt. Mit Hilfe eines Luziferase Reportergenassays und Chromatinimmunpräzipitation wurde die Aktivierung des Transkriptionsfaktors NF-kappaB untersucht. Im Rahmen dieser Arbeit konnte nachgewiesen werden, dass die spezifische Interaktion von CEACAM3 mit M. catarrhalis UspA1 in einer Aktivierung neutrophiler Granulozyten resultiert. Desweiteren kommt es zu einer CEACAM3-UspA1 abhängigen Aktivierung des Transkriptionsfaktors NF-kappaB und verstärkter Sekretion proinflammatorischer Chemokine. Die NF-kappaB-Aktivierung ist abhängig von der Phosphorylierung des CEACAM3 ITAM-like Motivs und erfolgt über den Syk und Card9 Signalweg. Die Ergebnisse lassen den Schluss zu, dass neutrophile Granulozyten in der Lage sind, die durch M. catarrhalis induzierte Atemwegsentzündung in der COPD über den Oberflächenrezeptor CEACAM3 spezifisch zu modulieren.
The chronic obstructive pulmonary disease (COPD) is the fourth most common cause of death worldwide. 25 % of the acute bacterial exacerbations are caused by infection with the human restricted pathogen Moraxella catharralis. Both the acute and the chronic inflammatory stage of COPD are predominantly determined by neutrophil granulocytes in the respiratory tract, which in addition to antimicrobial effector functions can also regulate the inflammation or immune response by releasing cytokines. This work investigated if the interaction of M. catarrhalis with the human granulocyte-specific receptor carcinoembryonic antigen-related cell adhesion molecule (CEACAM) 3 leads to an activation of the neutrophil granulocytes and to a NF-kappaB-dependent chemokine production. Primary granulocytes from healthy donors as well as NB4 cells were infected with M. catarrhalis in the presence of various inhibitors, siRNA or CEACAM-blocking antibodies, and then chemokine secretion was determined by ELISA. Using a luciferase reporter gene assay and chromatin immunoprecipitation, activation of the transcription factor NF-kappaB was investigated. In this work it could be shown that the specific interaction of CEACAM3 with M. catarrhalis UspA1 results in the activation of neutrophil granulocytes. Furthermore, there is a CEACAM3-UspA1-dependent activation of the transcription factor NF-kappaB and increased secretion of proinflammatory chemokines. NF-kappaB activation is dependent on the phosphorylation of the CEACAM3 ITAM-like motif and occurs via the Syk and Card9 signaling pathways. The results suggest that neutrophil granulocytes are able to specifically modulate M. catarrhalis induced airway inflammation in COPD via the surface receptor CEACAM3.

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18

Serrano, Aybar Pablo. "Mechanisms of induction of CCL20/MIP3-α in lung epithelial cells by Moraxella catarrhalis." University of Toledo Health Science Campus / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=mco1222875028.

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19

Cumbes, Bevan Christopher. "Responses of the Opportunistic Pathogen Moraxella (Branhamella) catarrhalis to Clinically Relevant Changes in Environmental Conditions." Thesis, University of the West of England, Bristol, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.524691.

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The Gram-negative bacterium, Moraxella ca tarrhalis, is an opportunistic human pathogen that colonises the nasopharynx of healthy individuals. The disease most often associated with this organism is otitis media in children, though it is increasingly implicated in lower respiratory tract infections and even some cases of meningitis, endocarditis and bacteraemia. The most commonly quoted sites of colonisation and infection are the nasopharynx, tympanic cavity and lower respiratory tract. The different microenvironments found at these infection sites suggest a range of conditions in which the bacterium is an effective pathogen. An investigation was undertaken to determine what effect changing between these environments had on the proteome of M. catarrhalis. The effect of temperature was examined by comparing protein expression between cultures grown at 26, 30, 35, 37 and 40°C and also following an up-shift in temperature from 30 to 37°C. The effect of pH was examined by shifting the growth media from pH 7.2 to either pH 6.5 or pH 8.0. The effect of oxygen was examined by growing M. catarrhalis in continuous culture with 5-6 % excess O2 and comparing this to M. catarrhalis grown with no excess O2 . Two dimensional electrophoresis and difference in-gel electrophoresis were used to separate out the proteins from whole cell Iysates and to measure the relative abundance of proteins that were affected by the test conditions. The number of proteins affected by temperature was: 51 at 26°C, 10 at 30°C, 9 at 35°C and 23 at 40°C. Up-shifting pH affected 12 proteins and down-shifting pH affected 12 separate proteins. 52 proteins were affected by restricting oxygen. In addition, the identities and positions of 60 proteins were found and used to produce the most complete annotated M. catarrhalis 20 proteomic map to date. Among those proteins found to be affected by changes in environmental conditions, isoforms of the adhesin Omp CO were found to increase when oxygen availability was reduced. Attempts were made to produce a knockout ompCD mutant but these proved unsuccessful, indicating that Omp CD may have a fundamentally important role in viability of M. catarrhalis strain NCTC 11020. The general porin M35 increased in reduced oxygen and during stationary phase, suggesting a role in modifying membrane permeability similar to that of its homolog Omp C from E. coli. An isogenic m35 knockout mutant showed reduced growth in nutrient poor media, was more tolerant of osmotic pressure, was killed more quickly by exposure to an anaerobic environment and was less able to autoagglutinate. The mutation affected little difference in ability to grow at different pH levels and there was no difference in susceptibility to gentamicin, or in cell morphology or membrane thickness. Also, there was no significant difference in adherence or invasion of human pharyngeal or alveolar epithelial cells compared to the wild type, indicating that M35 is not a virulence factor

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20

Zabel, Solveig. "Die Bedeutung von CEACAM1 für die Moraxella-catarrhalis-induzierte TLR2-vermittelte Aktivierung des respiratorischen Epithels /." Berlin : Mbv, Mensch- & -Buch-Verl, 2009. http://d-nb.info/998778087/04.

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21

JAGER, BEAUVEIL AURELIE. "Activite in vitro comparee de differents antibiotiques vis-a-vis de streptococcus pneumoniae, haemophilus influenzae et moraxella catarrhalis : enquete epidemiologique au c.h.r. de metz au cours de l'annee 1990." Nancy 1, 1993. http://www.theses.fr/1993NAN1A202.

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Zabel, Solveig [Verfasser]. "Die Bedeutung von CEACAM1 für die Moraxella catarrhalis-induzierte TLR2-vermittelte Aktivierung des respiratorischen Epithels / Solveig Zabel." Berlin : Freie Universität Berlin, 2010. http://d-nb.info/1024004317/34.

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23

Carbonneau, Julie. "Caractérisation de la réponse immune naturellement acquise chez l'homme au cours de la colonisation avec Moraxella (Branhamella) catarrhalis." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0004/MQ43791.pdf.

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24

Zahradnik, Sabrina [Verfasser]. "Die M. catarrhalis – induzierte Verminderung viraler Rezeptoren und deren Bedeutung für die antivirale Immunantwort in pulmonalem Epithel / Sabrina Zahradnik." Berlin : Freie Universität Berlin, 2014. http://d-nb.info/1048047431/34.

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25

Westman, Eva. "Experimental acute otitis media : aspects on treatment, protection and structural changes." Doctoral thesis, Umeå : Univ, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-162.

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26

Taylor, LaShan Denise. "Antibiotic Resistance: Multi-Drug Profiles and Genetic Determinants." [Johnson City, Tenn. : East Tennessee State University], 2001. http://etd-submit.etsu.edu/etd/theses/available/etd-1210101-134219/unrestricted/taylorl121101a.pdf.

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Steiner, Tamara Alice [Verfasser]. "Die Bedeutung des humanen β-Defensin-3 für die Infektion von humanem respiratorischem Epithel mit Moraxella catarrhalis / Tamara Alice Steiner." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2014. http://d-nb.info/1052221475/34.

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Beeck, Andreas. "Molekularepidemiologische Charakterisierung der BRO-[beta]-Laktamasen [BRO-beta-Laktamasen] europäischer Moraxella catarrhalis Isolate und Analyse der In-vitro-Aktivität verschiedener Antibiotika." [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=971101582.

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Balder, Rachel. "Type V Secretion System Exoproteins and their Roles in the Adherence of the Gram-Negative Bacterial Pathogens Moraxella catarrhalis, Burkholderia pseudomallei and Burkholderia mallei." University of Toledo Health Science Campus / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=mco1188909479.

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Uskudar, Guclu Aylin. "Identification Of Streptococcus Pneumoniae, Haemophilus Influenzae, And Moraxella Catarrhalis From Sputum Samples Of Patients With Community Acquired Pneumonia By Polymerase Chain Reaction." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12605920/index.pdf.

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iv The present work describes the evaluation of the value of polymerase chain reaction in diagnosis of pneumonia caused by the most common three bacterial pathogens
Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis from sputum of patients with community acquired pneumonia admitted to The Department of Pulmonary Diseases of Gulhane Military Medical Academy. In this study, 107 sputa from 142 patients with suspected community acquired pneumonia were used to survey the causative agents. Identification of the pathogens was performed by sputum Gram stain and conventional microbiological methods. Polymerase chain reaction was performed to investigate the presence of S.pneumoniae, H.influenzae, and M.catarrhalis for the same sputum samples as well. PCR products were processed by electrophoresis on 2% agarose gels with visualization of the amplicon with ethidium bromide and UV illumination. The 33 of 107 samples were positive in cultures and 67 in PCR. S.pneumoniae (48.5%) was the most common etiologic agent as to PCR analysis. The incidences of H.influenzae and M.catarrhalis were determined as 18.6%, and 4.7% respectively. The incidence of S.pneumoniae in patients with CAP and control group individuals were almost the same. The sputum PCR positives were higher than those reported carriage rates for these three microorganisms. 9 of 107 patients with PCR-positive had evidence of infection with pathogens other than S.pneumoniae. The results indicated that some of the PCR results were false positive due to oropharyngeal contamination. PCR testing of sputum samples for diagnosing pneumococcal pneumonia is unable to distinguish colonization from infection in some circumstances. To distinguish the colonization from infection, sputum Gram stain should be applied to the sputum specimens. Because of being faster and easier, PCR looks like becoming more reliable technique by the using of valid specimens from patients with community-acquired pneumonia if supported by quantitative techniques.

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Heinrich, Annina [Verfasser], Arturo [Gutachter] Zychlinsky, Hortense [Gutachter] Slevogt, and Ralf [Gutachter] Schumann. "Die Bedeutung von CEACAM3 für die Moraxella catarrhalis induzierte Aktivierung von humanen Granulozyten / Annina Heinrich ; Gutachter: Arturo Zychlinsky, Hortense Slevogt, Ralf Schumann." Berlin : Humboldt-Universität zu Berlin, 2018. http://d-nb.info/1185495614/34.

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Bergström, Jennie. "Nested PCR for distinguishing Haemophilus haemolyticus from Haemophilus influenzae and Cloning and expression of fragmented Moraxella catarrhalis IgD-binding protein in E. coli." Thesis, Uppsala University, Department of Medical Biochemistry and Microbiology, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8014.

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ABSTRACT

Nontypable Haemophilus influenzae is a common cause of otitis, sinusitis and conjunctivitis. It is the most common bacterial pathogen associated with chronic obstructive pulmonary disease (COPD). Studies have shown that nonpathogenic Haemophilus haemolyticus are often mistaken for Haemophilus influenzae due to an absent hemolytic reaction on blood agar. Distinguishing H. haemolyticus from H. influenzae is important to prevent unnecessary antibiotic use, and to understand the role of H. influenzae in clinical infections. In this study, PCR-primers for amplifying 16S rDNA sequences were used to set up a method for distinguishing H. haemolyticus from H. influenzae. The aim was to use the method for analyzing apparent H. influenzae strains, to investigate if some strains were in fact H. haemolyticus. However, because of problems with unspecific primerannealing,no conclusions could be drawn regarding misclassification of H. haemolyticus.

Moraxella catarrhalis is the second most common bacterial pathogen associated with COPD. It also causes otitis and sinusitis. An important virulence factor of M. catarrhalis is the outer membrane protein Moraxella catarrhalis IgD-binding protein (MID). One part of the protein; MID764-913 , has been shown to function as an adhesin, and this part has been fragmented to further investigate its adhesive properties. The aim of this second, independent study, was to express some of these proteinfragments by cloning in E. coli. The time spent on this project was too short, and no proteins could be expressed duing this period.

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Tiwari, Krishna Nand [Verfasser]. "Vergleich unterschiedlicher Methoden zur Quantifizierung der Adhäsion von Moraxella catarrhalis an pulmonalen Epithelzellen und Etablierung eines neuen Fluoreszenz-basierten Adhäsionsassays / Krishna Nand Tiwari." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2010. http://d-nb.info/1027814549/34.

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34

Alnahas, Safa [Verfasser], and Ulrich [Akademischer Betreuer] Steinhoff. "IL-17 and TNF-alpha are essential mediators of M. catarrhalis triggered exacerbation of HDM allergic airway inflammation / Safa Alnahas ; Betreuer: Ulrich Steinhoff." Marburg : Philipps-Universität Marburg, 2017. http://d-nb.info/1137323345/34.

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Qaiem, Maqami Lily [Verfasser]. "Die Bedeutung der Protein-Kinase C und ihrer Isoformen für die Moraxella catarrhalis induzierte IL-8-Sekretion in humanem pulmonalen Epithel / Lily Qaiem Maqami." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2011. http://d-nb.info/1025239954/34.

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Erman, Evelina. "Analys av antikroppar mot Moraxella catarrhalis hos patienter med multipelt myelom, Waldenströms makroglobulinemi och monoklonal gammopati av oklar signifikans med ”enzyme-linked immunosorbent assay”." Thesis, Linnéuniversitetet, Institutionen för naturvetenskap, NV, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-8301.

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Försämrat immunförsvar och ökad risk att drabbas av bakterie- och virusinfektioner förekommer hos patienter med blodsjukdomarna multipelt myelom, Waldenströms makroglobulinemi samt hos vissa patienter med blodsjukdomen monoklonal gammopati av oklar signifikans. Infektionerna kräver ofta antibiotikabehandling och behandling med antivirala medel. I dagsläget är det svårt att förutsäga vilka av patienterna som kommer att drabbas av svåra och ibland livshotande infektioner. Därför ges många av patienterna förebyggande antibiotikabehandling. I studiens början sattes en enzyme-linked immunosorbent assay (ELISA) för detektion av antikroppar mot Moraxella catarrhalis upp. I studien undersöktes om antikroppstitrar i serum mot bakterien Moraxella catarrhalis var lägre hos patientgrupperna än hos friska kontrollpersoner i samma ålder och om variationer förekom mellan patientgrupperna samt hur kontrollgrupper i olika åldrar skiljde sig från varandra. Kontrollgrupperna som undersöktes var mellan 20-40 år, 40-60 år samt 60 år och äldre. Resultatet var att patienterna med multipelt myelom hade lägst antikroppstitrar, patienter med monoklonal gammopati av oklar signifikans hade något högre och patienter med Waldenströms makroglobulinemi hade ännu högre antikroppstitrar. Kontrollgruppen äldre än 60 år hade högre antikroppstitrar än både kontrollgruppen 20-40 år och 40-60 år. Lägst antikroppstitrar hade kontrollgrupp 40-60 år men ingen signifikant skillnad påvisades mellan kontrollgrupp 20-40 år och 40-60 år.

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Al-Saadi, M. H. "Pathogenesis of malignant catarrhal fever in cattle." Thesis, University of Liverpool, 2018. http://livrepository.liverpool.ac.uk/3025852/.

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38

Sharp, Colin Peter. "The molecular basis of malignant catarrhal fever." Thesis, University of Edinburgh, 2007. http://hdl.handle.net/1842/29991.

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Alcelaphine herpesvirus-1 (A1HV-1) is gammaherpesvirus that can cause the devastating, fatal disease malignant catarrhal fever (MCF) in susceptible ruminant hosts but not in its natural host the blue wildebeest. The purpose of this study is to characterise four unique open reading frames (ORFs) of A1HV-1 and examine their contribution to viral pathogenesis. These ORFs are located at the left hand end of the genome, a region known to contain unique transforming and immunomodulatory genes in other gammaherpesviruses, and are predicted to encode two small gene products with no significant homology to any known proteins (ORF A1 and ORF A4), a transcription factor (ORF A2) and a member of the semaphorin family (ORF A3). A 6.2 Kb fragment from A1HV-1 containing all four ORFs under their natural promoters was cloned into the left hand end region of murine gammaherpesvirus-76 (MHV-76). This allowed for the study of the in vivo contribution to pathogenesis of the gene products in a well characterised small animal model. The recombinant virus showed no difference in its ability to replicate in vitro. Viral titres and lung pathology in infected mice were also comparable although the A1HV-1 gene transcripts were detectable. The ORF A2 gene product expressed as a recombinant fusion protein in mammalian cells consistently showed nuclear localisation, supporting the prediction that this protein functions as a transcription factor. The four left hand end genes were also used to screen a novel bovine cDNA library in a yeast two-hybrid system. Analysis of the bait constructs used indicated that there is a domain or domains in the C-terminus of the ORF A2 gene product capable of interacting with DNA or DNA binding proteins, again supporting a role for this protein as a transcription factor.

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Swa, Sandi. "Large granular lymphocyte dysregulation in malignant catarrhal fever." Thesis, University of Edinburgh, 2001. http://hdl.handle.net/1842/30020.

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The role of virus-infected large granular lymphocytes in pathogenesis of MCF is not clear. In the absence of defined viral antigens the main objective of this study was to investigate how MCF viruses interfere with LGL proliferation and cytotoxicity. In this study, IL-2 independence and a cell surface phenotype of T/NK cells was demonstrated in most cell lines analysed. The period of survival and growth without exogenous IL-2 was variable but always exceeded that of uninfected control cells. The possible role of IL-15 (a pro-inflammatory cytokine with actions similar to IL-2) in LGL function was investigated. Results showed that IL-15 could generate and maintain the proliferative and cytotoxic phenotype of these cell lines and may be involved in the pathogenesis of MCF. The identify of specific virus proteins involved in generating the observed phenotype of the LGL cell lines had not been determined. During the course of this study, the complete genomic sequence of the A1HV-1 genome was published. Prior to this several open reading frames were detected in A1HV-1 that underwent genomic rearrangement on transition from virulence to attenuation in vitro. Thus, a final objective of this study was to determine whether these potential virulence genes are associated with the ability of LGL cell lines to transmit disease. The proteins encoded by these genes (ORF50, A6 and A7) were expressed in E. coli as recombinant proteins and used to immunise rabbits. Recombinant virus protein-specific rabbit polyclonal antibodies were generated. Using these reagents, the expression of these proteins in LGL cell lines and A1HV-1-infected monolayer cultures was investigated. The polymerase chain reaction (PCR) was used in parallel experiments to determine the presence of DNA and mRNA encoding these proteins. The results indicated that more complicated rearrangements of the A1HV-1 genome may occur on attenuation of A1HV-1 after extensive passage than has been revealed at present. However, the expression in LGL cells of proteins encoded by ORF50 and A5, that share sequence homology with the EBV R and Z transctivators, suggests that virus replication occurs in LGL cells.

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Esnault, Olivier Bertagnoli Stéphane. "Étude sur l'analyse de risque de la Fièvre Catarrhale Ovine (Bluetongue) dans le bassin ovin laitier de Roquefort cas particulier des centres d'insémination artificielle /." [S.l.] : [s.n.], 2008. http://oatao.univ-toulouse.fr/2086/1/debouch_2086.pdf.

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Hemati, Behzad. "Interactions entre le virus Bluetongue et cellules dendritiques lymphatiques du mouton." Versailles-St Quentin en Yvelines, 2008. http://www.theses.fr/2008VERS0051.

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Le virus de la fièvre catarrhale ovine (Bluetongue virus, BTV) est un orbivirus de la famille des Reoviridae. Il comprend 24 sérotypes et il est responsable d’une maladie hémorragique transmise par des insectes chez les ruminants, qui génère des pertes économiques importantes dans le monde entier. La sévérité de la maladie et la durée de la virémie varient entre sérotypes et hôtes du BTV. La réponse innée pourrait être impliquée dans la sensibilité de l’hôte à l’infection mais elle est très peu connue. Pour aborder l’étude de cette réponse innée chez l’hôte, nous avons étudié la dissémination du BTV et la production d’interféron (IFN) de type I dans la lymphe afférente chez le mouton juste après administration intra-cutanée. Nous avons montré que le BTV migre associée aux cellules dendritiques conventionnelles (cDC) de la lymphe afférente. Tous les sérotypes étudiés de BTV s’expriment et produisent des particules infectieuses dans les cDC, indépendamment de l’atténuation virale. L’expression du BTV favorise la survie des cDC et conduit à une augmentation d’expression du CD80, du CD86 et d’ARN messagers codant pour l’IL12, IL1β et IL6. Les cDC infectées par le BTV induisent la prolifération de lymphocytes immuns T CD4pos et CD8pos et la production d’IFN. Le BTV utilise donc les cDC pour sa première étape de dissémination lymphatique sans altérer leurs fonctions immunes, ce qui suggère une adaptation optimale du virus à sa première cible cellulaire. Par ailleurs, l’injection intra-cutanée de BTV induit la production d’IFN de type I dans la lymphe en 2 pics (à 24 h et à 5-6 jours après inoculation) en parallèle de la dissémination virale. Seules les cellules dendritiques plasmacytoides (pDC) - à la différence des cDC lymphatiques - sont capables de produire de l’IFN de type I en réponse au BTV, indépendamment du sérotype et la réplication virale ou de l’acidification endosomale. Globalement ces approches suggèrent l’hypothèse selon laquelle la réplication du BTV et/ou les réponses des cDC et pDC au BTV pourraient être impliquées dans la susceptibilité individuelle au virus
Bluetongue virus (BTV), an orbivirus of the reoviridae family comprises 24 serotypes and is responsible for an insect transmitted hemorrhagic disease in ruminants that generates important economic losses all over the world. The severity of the BTV induced syndrome as well as the duration of viraemia greatly varies between BTV serotypes and hosts. The innate response to the virus could be involved in host sensitivity and has not been studied. We investigated the first steps of BTV dissemination and type I IFN response in the afferent lymphatic in sheep, right after intra-cutaneous delivery of the virus. We showed that BTV initially migrates in the skin draining lymph mainly associated to conventional dendritic cells (cDC). Lymph cDC supported BTV RNA, protein and infectious virus production of several serotypes, independently of viral attenuation. BTV expression in cDC did not impair their survival but rather favored it. Interaction of BTV with cDC preparation resulted in an increased expression of CD80 and CD86 as well as an increase in IL12, IL1b and IL6 mRNA expression. Finally lymph cDC cultured with BTV triggered stimulation of specific CD4 and CD8 T cell proliferation as well as IFNg production. BTV thus utilizes cDC for its first lymph dissemination step in the host without altering their classical immune function of antigen presentation, reflecting an optimal adaptation of the virus to its first cell target. Besides, we found that type I IFN is detectable in 2 peaks (24 hours and day 5 - 6) in afferent lymph in parallel to the viral dissemination. Only lymph plasmacytoid (pDC) and not cDC were producing type I IFN (IFNa) to BTV, independently on viral serotype, on viral replication and on endosomal acidification. Collectively these finding suggest the hypothesis that BTV replication in cDC and/or cDC and pDC responses might be involved in inter-individual susceptibility to BTV

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Lankester, Felix John. "The impact and control of malignant catarrhal fever in Tanzania." Thesis, University of Glasgow, 2016. http://theses.gla.ac.uk/7769/.

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Malignant Catarrhal Fever (MCF), an often-lethal infectious disease, presents as a variable complex of lesions in susceptible ungulate species. The disease is caused by a -herpesvirus following transmission from an inapparent carrier host. Two major epidemiological forms exist: wildebeest-associated MCF (WA-MCF), in which the virus is transmitted to susceptible species by wildebeest calves less than approximately four months of age, and sheepassociated MCF (SA-MCF) in which the virus is spread by sheep (primarily adolescents). Due to the lack of an in-vitro propagation system for the causative agent of the more economically significant SA-MCF, and with the expectation that cross-protective immunity may be provided, vaccine development has focused on the more easily propagated alcelaphine herpesvirus-1 (AlHV-1) that causes WA-MCF. In 2008 a direct viral challenge trial showed that a novel vaccine, employing an attenuated AlHV-1 (atAlHV-1) `C5000 virus strain, protected British Friesian-Holstein (FH) cattle against an intranasal challenge with virulent AlHV-1 `C5000 virus. For cattle keeping people living near wildebeest calving areas in sub-Saharan Africa an effective vaccine would have value as it would release them from the costly annual disease avoidance strategy of having to move their herds away from the oncoming wildebeest. On the other hand, an effective vaccine will release herd owners from the need to avoid MCF, allowing them to graze their cattle alongside wildebeest on the highly nutritious pastures of the calving areas. As such conservationists have raised concerns that the development of a vaccine might lead to detrimental grazing competition. The principle objective of this study was to test the novel vaccine on Tanzanian shorthorn zebu cross cattle (SZC).We did this firstly using a natural challenge field trial (Chapter Two) which demonstrated that immunisation with the atAlHV-1 vaccine was well tolerated and induced an oro-nasopharyngeal AlHV-1-specific and -neutralising antibody response. This resulted in an immunity in SZC cattle that was partially protective and reduced naturally transmitted infection by 56%. We also demonstrated that non-fatal infections occurred with a much higher frequency than previously thought. Because the calculated efficacy of the vaccine was less than that seen in British FH cattle we wanted to determine whether host factors, particular to SZC cattle, had impacted the outcomes of the field trial. To do this we repeated the 2008 direct viral challenge trial using SZC cattle (Chapter Four). During this trial we also investigated whether the recombinant bacterial flagellin monomer (FliC), when used as an adjuvant, might improve the vaccine’s efficacy. The findings from this trial indicated that direct challenge with pathogenic AlHV-1 is effective at inducing MCF in SZC cattle and that FliC is not an appropriate adjuvant for this vaccine. Furthermore, with less control group cattle dying of MCF than expected we speculate that SZC cattle may have a degree of resistance to MCF that affords them protection from infection and developing fatal disease. In Chapter Three we investigated aspects of the epidemiology of MCF, specifically whether wildebeest placenta, long implicated by Maasai cattle owners as a source of MCF, might play a role in viral transmission. Additionally, through comparative sequence analysis, at two specific genes (A9.5 and ORF50) of wild-type and atAlHV-1, we investigated whether the `C5000 strain, the source of which was taken from Africa more than 40 years ago, was appropriate for vaccine development. The detection of AlHV-1 virus in approximately 50% of placentae indicated that infection can occur in-utero and that this tissue might play a role in disease transmission. And, despite describing three new alleles of the A9.5 gene (supporting previous evidence that this gene is polymorphic and encodes a secretory protein with interleukin-4 as the major homologue), the observation that the most frequently detected haplotypes, in both wild-type and attenuated AlHV-1, were identical suggests that AlHV-1 has a slow molecular clock and that the attenuated strain was appropriate for vaccine development. In Chapter Five we present the first quantitative assessment of the annual MCF avoidance costs that Maasai pastoralists incur. In particular we estimated that as a result of MCF avoidance 64% of the total daily milk yield during the MCF season was not available to be used by the 81% of the family unit remaining at the permanent boma. This represents an upper-bound loss of approximately 8% of a household0s annual income. Despite these considerable losses we concluded that, given an incidence of fatal MCF in cattle living in wildebeest calving areas of 5% to 10%, if herd owners were to stop trying to avoid MCF by allowing their cattle to graze alongside wildebeest, any gains made through increased availability of milk, improved body condition and reduced energy demands would be offset by an increase in MCF-incidence. With the development of an effective vaccine, however, this alternative strategy might become optimal. The overall conclusion we draw therefore is that, despite the substantial costs incurred each year avoiding MCF, the partial protection afforded by the novel vaccine strategy is not sufficient to warrant a wholesale change in disease avoidance strategy. Nonetheless, even the partial protection provided by this vaccine could be of value to protect animals that cannot be moved, for example where some of the herd remain at the boma to provide milk or where land-use changes make traditional disease avoidance difficult. Furthermore, the vaccine may offer a feasible solution to some of the current land-use challenges and conflicts, providing a degree of protection to valuable livestock where avoidance strategies are not possible, but with less risk of precipitating the potentially damaging environmental consequences, such as overgrazing of highly nutritious seasonal pastures, that might result if herd owners decide they no longer need to avoid wildebeest.

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Kumati, Osama B. Mohamed. "Virus life cycle and the parthenogenesis of malignant catarrhal fever." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/38034/.

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Malignant catarrhal fever (MCF) is caused by two closely associated gamma herpes viruses namely alcelaphine herpesvirus 1 (AlHV-1) and ovine herpesvirus 2 (OvHV-2) and characterised with lymphocyte infiltration in non-lymphoid tissues, vasculitis and epithelial damage. The mechanism by which the viruses cause the disease is not fully understood. The hypothesis of this project was that MCF is initiated by aberrant gene expression in endothelium, epithelium and infected T cells of susceptible animals, because they are not the natural hosts for the viruses and the viruses will not have evolved in them. The first goal was to examine whether rabbit epithelium and bovine endothelium can be infected in vitro and in vivo with AlHV-1 using q PCR and, if infected whether viral transcripts could be identified in these tissue cells using q PCR and in situ hybridisation (ISH). The results revealed that endothelium and epithelium can be infected and latent infection can be established in them. This suggests the likelihood of establishing a similar type of infection in vivo. Secondly, the trial to identify latency-associated transcripts using 5-azacitidine treatment on bovine turbinate fibroblast (BT) cells and rabbit large granular lymphocytes (LGLs) was only partially successful. However, pan T antigen was expressed in 5-azacitidine treated but not untreated LGLs cells. This may indicate a function of the drug either directly or through the latency state. Transcriptome analysis in the infected and treated LGLs and BT cells showed that several pathways were affected by 5-aza although a possible latency (low transcript levels) was only seen in the BTs. Transcriptome analysis revealed similar pathways to those described for MCF in the tissues in vivo, and an effect of 5-aza on these. Viral transcripts analysis showed that genes related to productive/lytic cycles were higher than latent ones on day 17 of the in vivo experiment demonstrating that the virus may replicate at this stage of the disease. The attempt to localize the viral transcripts on the rabbit infected tissues using ISH was unsuccessful due to a lack of time.

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Schock, Alexandra. "Characterisation of the T-cell proliferation in malignant catarrhal fever." Thesis, University of Edinburgh, 1996. http://hdl.handle.net/1842/29987.

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Malignant catarrhal fever (MCF) is a lethal lymphoproliferative disorder of cattle and deer caused by infection with either Alcelaphine Herpesvirus-1 (AHV-1) or Ovine Herpesvirus - 2 (OHV-2). It was proposed that the viruses induce an interleukin-2 (IL-2) hyperproduction which is responsible for the lymphoid cell hyperplasia observed. The hyperplasia of lymph node cells was investigated by examining the growth characteristics of freshly explanted lymph node cells from AHV-1 infected rabbits. The lymph node cells had a higher thymidine uptake respective to control cultures in the first 24 hours. IL-2 increased viability and thymidine uptake and Con A did not stimulate these cells as expected. Very little IL-2 activity could be detected in supernatants from short term cultures using the CTLL-based bioassay. To establish a TR-PCR/immunoblot for the detection of rabbit IL-2 mRNA, IL-2 cDNA from Con A stimulated rabbit lymphocytes was cloned and partially sequenced. IL-2 transcripts could be detected in lymphoid cells from pyrexic rabbits with AHV-1 and in cells from control rabbits. Furthermore, it was shown that lymphoblastoid cell lines (LCL) derived from MCF-affected cattle did not transcribe IL-2. These data lead to the conclusion that IL-2 is involved in the acute state of MCF, but does not have a central role in the pathogenesis. Further characterisation of IL-2 dependent LCL showed that they responded weakly to Con A, were inhibited by Cyclosporin A and transcribed constitutively IL-4, IL-10, INFγ and TNFα, whereas no IL-1β mRNA could be detected. These data together with the results derived from the short term cultures of lymph node cells from AHV-1 infected rabbits clearly show that MCF inducing viruses alter the behaviour of lymphoid cells. The possible interference of OHV-2 and AHV-1 with transductional pathways, the expression of IL-2R and the activation of self-reacting lymphocytes are discussed.

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Chauveau, Emilie. "Etude des mécanismes d'induction et de contrôle de la production d'interféron par le virus de la Bluetongue dans les cellules non-hématopoïétiques." Paris 7, 2012. http://www.theses.fr/2012PA077235.

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La fièvre catarrhale ovine est une maladie hémorragique sévère chez les ruminants, transmise par des moucherons, les Culicoides. L'agent étiologique de cette maladie est le virus de la langue bleue, pour Bluetongue virus (BTV) en anglais. C'est un virus à ARN double brin (ARNdb), appartenant au genre Orbivirus au sein de la famille des Reoviridae. Depuis longtemps, il a été montré que le BTV induit la production d'interféron. Cependant les récepteurs cellulaires et la voie de signalisation impliqués dans cette production restent inconnus. Le but de ce projet est de les identifier et d'évaluer la capacité du BTV à moduler la synthèse de l'IFN de type I (IFN-i), comme le font de nombreux virus. Comme attendu, en réponse à une infection par le BTV, des cellules épithéliales ou endothéliales humaines et bovines ont montré une forte production d'IFNβ. Cette production s'est révélée dépendante de la réplication virale et induite par les ARN hélicases, RIG-I et MDA5. Ces ARN hélicases peuvent activer la synthèse d'IFN-I en présence d'ARNdb du BTV dans un modèle de cellules humaines. Cette réponse antivirale entraîne le contrôle de la réplication du BTV. De plus, nous avons montré que le BTV de sérotype 8 (BTV-8) peut bloquer la voie IFN-I et que la protéine non-structurale NS3 est impliquée dans ce mécanisme. NS3 inhibe spécifiquement la production des transcrits activée par la voie de synthèse de l'IFN-I. L'action de NS3 pourrait intervenir entre MAVS et le complexe TBK1/IKKε dans la voie des RIG-like re��cepteurs mais son mécanisme d'action reste à déterminer
Bluetongue disease is a severe hemorragic disease in ruminant, transmitted by midges from the genus Culicoides. Bluetongue virus (BTV) is the etiologic agent of the disease. This double stranded RNA (dsRNA) virus is an Orbivirus, belonging to the Reoviridae family. It has been reported for a long time that BTV infection induces interferon production. However the cellular sensors and signaling pathways involved in this process remain unknown. The aim of this project is to identify them and to evaluate the capacity of BTV to modulate type I IFN (IFN-I) synthesis, as other viruses do. As expected, in response to BTV infection, human and bovine cells showed a strong production of IFN[3. This production is dependent on viral replication and mediated through the RNA helicases, RIG-I or MDA5. These RNA helicases can activate IFNO production by sensing the dsRNA of BTV in a human cellular model. This antiviral response leads to the control of BTV replication. Furthermore, we found that BTV serotype 8 (BTV-8) can dampen the IFN-I pathway and that the non structural protein 3 (NS3) is involved in this process. NS3 specifically inhibits the transcripts production activated by the IFN-I production pathway. NS3 seems to target a protein involved in the RIG¬like receptor (RLR) pathway between MAVS and TBKVIKKe complex, but its mechanism of action remains to determine

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Perrin, Aurélie Anne. "Contribution au développement de vaccins capripoxviraux recombinants contre la fièvre catarrhale ovine." Montpellier 2, 2007. http://www.theses.fr/2007MON20134.

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La Fièvre Catarrhale Ovine est une maladie infectieuse, virale, non contagieuse affectant les ruminants domestiques et sauvages. L'importance économique de cette maladie est liée d'une part aux pertes directes (mortalité, avortements) et indirectes (mauvaise qualité de la laine, retard de croissance) observées sur les animaux infectés et d'autre part au blocage des frontières limitant les exportations. Le virus de la FCO appartient à la famille des Reoviridae et au genre Orbivirus. Il est transmis essentiellement par des moucherons hématophages du genre Culicoides (Diptera: Ceratopogonidae). Il existe, à l'heure actuelle, 24 sérotypes dont 6 en Europe. La stratégie vaccinale actuelle consiste à utiliser des vaccins à virus atténué ou à virus inactivé. Cependant, ces vaccins spécifiques d'un sérotype donné ne protègent pas en cas d'épizooties dues à plusieurs sérotypes. L'utilisation de vaccins multivalents est alors jusqu'ici nécessaire. L'objectif de ce travail de thèse est le développement de vaccins dits de « nouvelle génération » induisant une protection de longue durée contre un maximum de sérotypes, en une seule injection. Pour se faire, la construction vaccinale repose sur une souche atténuée du virus de la dermatose nodulaire contagieuse (Capripoxvirus: Poxviridae) exprimant différents gènes choisis du virus de la FCO. Ainsi, quatre virus recombinants distincts exprimant individuellement les protéines structurales VP2, VP7 ou les protéines non structurales NS1, NS3 du virus de la FCO ont été générés par recombinaison homologue et testés in vivo. Une réponse immunitaire, de type humorale et cellulaire, à la fois contre le vecteur viral et contre les transgènes, ainsi qu'une protection partielle ont été mises en exergue après à une épreuve homologue par le biais d'expérimentations animales menées sur chèvres et moutons

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Courtejoie, Noémie. "Modélisation de la dynamique et du contrôle de la fièvre catarrhale ovine en France." Thesis, Paris Est, 2019. http://www.theses.fr/2019PESC0013.

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Le sérotype 8 du virus de la fièvre catarrhale ovine (BTV-8) s’est largement propagé en France en 2007/09 et a eu un fort impact économique. La vaccination, d’abord obligatoire puis facultative, a permis de recouvrer un statut indemne fin 2012, mais l’épizootie a repris en 2015. Il est possible que le BTV-8 n’ait jamais cessé de circuler. Cette thèse visait à clarifier l’épidémiologie du BTV-8 de l’émergence à la réémergence et à apporter une analyse critique des modalités de surveillance et de contrôle, à l’aide de méthodes variées de modélisation. Par des analyses de facteurs de risque, nous avons caractérisé l’immunité des bovins au moment de la réémergence et mis en évidence une circulation antérieure du BTV-8. Par des modèles catalytiques développés dans un contexte bayésien, nous avons ajouté une dimension temporelle, estimé l’ampleur de l’infection, séparé la contribution de mécanismes de séroconversion (infection et vaccination) et de transmission (vectorielle et transplacentaire), estimé la probabilité de transmission verticale (> 50 % en 2016), et évalué la vaccination facultative (peu suivie en 2011/12, avec des contrastes régionaux). Nous avons synthétisé l’ensemble des informations disponibles et développé un modèle mathématique, dynamique et stochastique, représentant différents mouvements d’hôtes et de vecteurs par des réseaux de contacts. Nous avons identifié les mesures ayant été efficaces (vaccination obligatoire, restrictions commerciales) et proposé une gestion alternative (ciblage de la vaccination en urgence en amont du front, contrôle des mouvements au pâturage). Enfin, nous avons apporté un faisceau d’arguments en faveur d’une circulation continue et non détectée du BTV-8
Bluetongue virus serotype 8 (BTV-8) spread throughout France in 2007/09 and had a strong economic impact. Vaccination, first mandatory then voluntary, allowed regaining a disease-free status in December 2012, but a new outbreak occurred in August 2015. BTV-8 may have kept circulating all along. The aim of this thesis was to clarify the epidemiology of BTV-8 from emergence to re-emergence and to provide a critical analysis of surveillance and control measures, using various modelling tools. Using risk factor analyses, we characterized the immunity of cattle at the time of re-emergence and detected low-level BTV-8 circulation prior to that date. Using catalytic models developed in a Bayesian context, we added a time dimension, we separated the contribution of seroconversion mechanisms (infection and vaccination) and transmission mechanisms (vector-borne and transplacental), we estimated the burden of infection and the probability of vertical transmission (> 50% in 2016), and we assessed the coverage of voluntary vaccination (poorly implemented in 2011/12, with regional contrasts). We synthesized all available information and developed a mathematical, dynamic and stochastic model, using contact networks to represent different types of host and vector movements. We identified the control measures that had been effective (mandatory vaccination, trade restrictions), and suggested alternative ones (targeting emergency vaccination ahead of the front, controlling movements on pastures). Finally, we provided arguments in favor of a continuous and undetected BTV-8 circulation

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Villard, Pierre. "Évaluation de l'impact et de l'efficacité de la surveillance et de la lutte de la fièvre catarrhale ovine en France." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1351.

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Le sérotype 8 du virus de la fièvre catarrhale ovine (FCO) avait eu un fort impact économique sur la filière bovine lors de l’épizootie entre 2006 et 2009 en France. Les travaux établis au cours de cette thèse visaient à évaluer l’impact financier de la circulation de la FCO après sa réémergence en 2015, et à apporter des éclairages nouveaux sur la dynamique des Culicoides, et sur les mesures de surveillance et de lutte. Par la récolte et l’analyse de données, nous avons pu calculer le coût des mesures de surveillance de septembre 2015 à décembre 2016 (14,6 M€ HT). Grâce à l’analyse des données historiques de mouvements de bovins, nous avons pu mettre en évidence les modifications de dynamique de mouvements pour les élevages en fonction de leur statut sanitaire, ainsi qu’estimer la surmortalité bovine lié à la circulation de la FCO. En utilisant des données de captures de Culicoides, nous avons pu établir un modèle pour la prévision de l’abondance de ces vecteurs, validant du même coup, l’usage de zones vectorielles dans la surveillance entomologique. Nous avons enfin utilisé un modèle existant afin de mettre en évidence la présence de différence selon plusieurs modalités de surveillance et de contrôle vis-à-vis de la FCO. Nous avons établi que la surveillance programmée ne présentait pas une efficience pertinente dans le contexte de détection d’une maladie à fort impact économique comme la FCO, tandis que les mesures de restriction de mouvements jouent un rôle incontournable dans la préservation de la filière bovine contre la FCO
Bluetongue virus (BTV) serotype 8 had a strong economic impact on the cattle industry during the epizootic between 2006 and 2009 in France. This thesis aimed to evaluate the financial impact of BTV diffusion after its re-emergence in 2015, and to bring new insights into the dynamics of Culicoides, and the surveillance and control system. By collecting and analyzing data, we were able to calculate the cost of surveillance system from September 2015 to December 2016 (€ 14.6 million excluding taxes). Thanks to the analysis of historical data on cattle movements, we were able to highlight changes in movement dynamics for farms according to their health status, as well as to estimate excess bovine mortality related to the circulation of BTV. By using catch data from Culicoides, we were able to establish a model for predicting the abundance of these vectors, validating at the same time the use of vector zones in entomological surveillance. We finally used an existing model to highlight results disparity according to several surveillance and control system against BTV. We have established that programmed surveillance does not provide relevant efficiency in the context of detecting a high-impact disease such as BTV, while movement restriction measures play an essential role in the preservation of the cattle industry against the BTV

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Bouet-Cararo, Coraline. "Evaluation d'un vaccin recombinant dérivé d'adénovirus canin chez le mouton : application à la fièvre catarrhale ovine (FCO)." Paris 11, 2010. http://www.theses.fr/2010PA114846.

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La Fièvre Catarrhale Ovine est due à un virus affectant les ruminants. Les vaccins actuellement disponibles (atténués ou inactivés) ne permettent pas, ou peu, de protection croisée entre les 24 sérotypes identifiés. Notre travail de thèse a consisté à développer chez le mouton des vaccins recombinants dérivés d’adénovirus canin de type 2 capables d’induire une protection contre un maximum de sérotypes
Bluetongue is a viral disease that affects Ruminants. Present vaccines (which are attenuated or inactivated vaccines) do not achieve complete cross protection against the 24 serotypes of the Bluetongue Virus (BTV). During this thesis different recombinant vaccines derived from the canine type 2 adenovirus have been developed to afford a broad protection in sheep against BTV

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Levy, Claire Safrai. "Identification and characterization of ovine herpesvirus 2 microRNAs." Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/6468.

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Ovine herpesvirus 2 (OvHV-2) is the causative agent of sheep-associated malignant catarrhal fever (MCF) in susceptible ruminants. Through an unknown mechanism, presence of the virus leads to proliferation of NK-like T cells that are not targetrestricted by the MHC class molecules. These host cells cause the symptoms found in MCF; fever, swollen lymph nodes, and necrotic lesions of the nasal, conjunctival, and oral mucosa, which usually leads to death of the host. MicroRNAs (miRNAs) are ~22 nt RNA molecules expressed by eukaryotes and viruses that regulate genes post-transcriptionally. Viral miRNAs have been found to regulate cellular genes to control the cell cycle and have a role in pathogenesis. It was hypothesised that OvHV-2 expresses miRNAs and these play a role in MCF pathogenesis. The aim of this project was to determine if OvHV-2 encodes miRNAs. Bioinformatic analysis was conducted on deep sequencing data from RNA of OvHV-2- immortalised T cells. Candidate miRNAs were selected if they adhered to miRNA secondary structure. 46 candidate miRNAs were found, with three clusters on the minus strand; one at the 5’ end and the other two in a 9.3 kb region that contains no predicted open reading frames. The 8 most abundant candidates were successfully validated by northern hybridisation for small RNAs. The majority of the predicted targets for the 8 validated OvHV-2 miRNAs were from the OvHV-2 genome. This study adds OvHV-2 to the list of herpesviruses that encode miRNAs and provides another tool for studying the pathogenesis of MCF.

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Dissertations / Theses on the topic 'Catarrhalis'

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