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Adherence to various host cell lines of Mycoplasma bovis strains differing in pathogenic and cultural features 总被引：1，自引：0，他引：1
Thomas A Sachse K Dizier I Grajetzki C Farnir F Mainil JG Linden A 《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 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. 相似文献
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Henning K Schares G Granzow H Polster U Hartmann M Hotzel H Sachse K Peters M Rauser M 《Veterinary microbiology》2002,85(3):285-292
Characteristics of an intracellularly growing micro-organism isolated from an aborted bovine foetus are described. The organism replicated within cytoplasmic vacuoles, was resistant to penicillin and exhibited structural characteristics compatible with Waddlia chondrophila. An ELISA specific for Chlamydia spp., immunofluorescence tests using antibodies directed against Chlamydia spp. or Simkania negevensis, and PCR using Chlamydia-specific primers showed that the agent was distinct from Chlamydiae or S. negevensis. Determination of 16S and partial 23S ribosomal RNA gene sequences in combination with the PCR results and the morphological, antigenic and developmental characteristics provided evidence that the isolate 2032/99 can be classified as W. chondrophila or a closely related organism. 相似文献
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E Berthold M Heller H Pfützner R Leirer K Sachse 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1992,39(5):353-361
Monoclonal antibodies (mabs) against Mycoplasma (M.) bovis were prepared for use in diagnosis of bovine mastitis. From the original 32 hybridomas actively secreting mabs against M. bovis, 6 stable lines were cloned. Two of them, Mb 5D8 and Mb 4F6, recognized M. bovis antigens of estimated molecular weights of 33 and 26 kDa, respectively. They showed no cross-reaction to other bovine mycoplasmas, thus rendering them useful for specific detection of this pathogen. All mabs investigated cross-reacted with M. agalactiae which is known to be closely related to M. bovis, but does not occur in cattle. Two other mabs, Mb 5D4 and Mb 1F6, exhibited further cross-reactions to a number of bovine mycoplasma species. Finally, mabs Mb 5D5 and Mb 2G5 reacted with all mycoplasmas tested. The possibility that they recognized constituents of the broth culture medium is discussed. 相似文献
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Publishers Note
Publisher's Announcement 相似文献7.
In the literature, studies of Chlamydia infection in birds have usually been confined to the search for Chlamydia (C., formerly Chlamydophila) psittaci, so that little is known about the presence of other chlamydial agents. In the present study, cloacal swabs and faeces samples of urban pigeons have been examined by real-time PCR, DNA microarray assays and partial ompA sequencing. Whilst C. psittaci was the predominant chlamydial agent in this pigeon population (75.8% of all Chlamydiaceae positives), the combined use of highly specific and sensitive molecular assays facilitated the detection of atypical serovars of C. psittaci, as well as other species of Chlamydia, such as C. abortus. Detection of C. pecorum and C. trachomatis from an avian host is reported here for the first time. Rather unexpectedly, 19.5% of all Chlamydiaceae-positive cases turned out to be infected with non-classified organisms. The considerable prevalence of these novel agents raises the question of their epidemiological importance and possible role as pathogens. Future surveys in domestic and wild birds will have to take the extended variety of chlamydial organisms into account. 相似文献
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Gaede W Reckling KF Dresenkamp B Kenklies S Schubert E Noack U Irmscher HM Ludwig C Hotzel H Sachse K 《Zoonoses and public health》2008,55(4):184-188
In 2005, an outbreak of severe respiratory disease in a mixed poultry flock that was infected with Chlamydophila (C.) psittaci led to dissemination of the infection to at least 100 small poultry farms in 11 districts of Central Germany. At the same time, a total of 24 persons in contact with poultry from one of the flocks reported flu-like symptoms to their physician, thus suggesting zoonotic transmission. Within 3 weeks, seven individuals had to be hospitalized, with three of them requiring intensive care. Analysis of ompA sequences from chlamydial isolates and directly from clinical samples revealed the presence of both genotype A and E/B of C. psittaci at the source of the outbreak and in contact flocks. Genotype A was also detected in the three severely ill patients. The findings of the present study demonstrate the high zoonotic potential of avian chlamydiae. To ensure speedy eradication of psittacosis in poultry flocks and effective treatment of infected humans, fast, sensitive and species-specific detection of the causative agent is essential, as well as close collaboration between regional public health services, attending physicians and the diagnostic laboratories involved. 相似文献
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Laroucau K de Barbeyrac B Vorimore F Clerc M Bertin C Harkinezhad T Verminnen K Obeniche F Capek I Bébéar C Durand B Zanella G Vanrompay D Garin-Bastuji B Sachse K 《Veterinary microbiology》2009,135(1-2):82-89
Five severe cases of psittacosis in individuals associated with duck farms were notified in France between January and March 2006. Diagnostic examination included serology and/or molecular detection by PCR from respiratory samples. As a consequence, we investigated all duck flocks (n=11) that were housed in the three farms where human infections occurred. While serology by complement fixation test was negative for all samples, cloacal and/or tracheal chlamydial excretion was detected by PCR in all three units. Notably, one duck flock was tested strongly positive in 2 of the 3 affected farms, and Chlamydophila (C.) psittaci strains were isolated from cloacal and/or tracheal swab samples from both farms. Human samples and duck isolates exhibited the same PCR-RFLP restriction pattern, which appeared to be an intermediate between genotypes A and B. Analysis of ompA gene sequences and comparison to those of the type strains showed that the isolates could not be strictly assigned to any of the generally accepted genotypes of C. psittaci. Further analysis by MLVA of the PCR-positive human samples revealed two distinct patterns, which were related to previously isolated C. psittaci duck strains. 相似文献
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Sachse K Vretou E Livingstone M Borel N Pospischil A Longbottom D 《Veterinary microbiology》2009,135(1-2):2-21
There are two main approaches to diagnosing infections by Chlamydia and Chlamydophila spp. in mammals and birds. The first involves the direct detection of the agent in tissue or swab samples, while the second involves the serological screening of blood samples for the presence of anti-chlamydial antibodies. Ultimately, the test that is used is dependent on the types of samples that are submitted to the diagnostic laboratory for analysis. The present paper gives an overview on methodologies and technologies used currently in diagnosis of chlamydial infections with emphasis on recently developed tests. The performance characteristics of individual methods, such as the detection of antigen in smears and in pathological samples, the isolation of the pathogen, various antibody detection tests and DNA-based methods utilising conventional and real-time PCR, as well as DNA microarray technology are assessed, and specific advantages and drawbacks are discussed. Further, a combination of a specific real-time PCR assay and a microarray test for chlamydiae is proposed as an alternative reference standard to isolation by cell culture. 相似文献