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91.
Pascale Gueirard Karine Le Blay Alain Le Coustumier Richard Chaby Nicole Guiso 《FEMS microbiology letters》1998,162(2):331-337
We previously reported the case of a human chronic Bordetella bronchiseptica respiratory infection, due to contact with infected rabbits. Lipopolysaccharides of the human isolates, of one rabbit isolate and of isolates from other origins were analyzed with sera from infected mice, rabbit and human. Antigenicity and length of the lipopolysaccharide molecules varied between isolates. We showed a progressive loss of O-chain during infection, associated with an enhanced susceptibility of the isolates to the bactericidal effect of normal serum. This observation suggests the existence of an intracellular niche which selects for strains with distinct lipopolysaccharide types. 相似文献
92.
Rui P. Silva Andrea M. DiVenere Dzifa Amengor Jennifer A. Maynard 《The Journal of biological chemistry》2022,298(3)
Infection by the bacterium Bordetella pertussis continues to cause considerable morbidity and mortality worldwide. Many current acellular pertussis vaccines include the antigen pertactin, which has presumptive adhesive and immunomodulatory activities, but is rapidly lost from clinical isolates after the introduction of these vaccines. To better understand the contributions of pertactin antibodies to protection and pertactin''s role in pathogenesis, we isolated and characterized recombinant antibodies binding four distinct epitopes on pertactin. We demonstrate that four of these antibodies bind epitopes that are conserved across all three classical Bordetella strains, and competition assays further showed that antibodies binding these epitopes are also elicited by B. pertussis infection of baboons. Surprisingly, we found that representative antibodies binding each epitope protected mice against experimental B. pertussis infection. A cocktail of antibodies from each epitope group protected mice against a subsequent lethal dose of B. pertussis and greatly reduced lung colonization levels after sublethal challenge. Each antibody reduced B. pertussis lung colonization levels up to 100-fold when administered individually, which was significantly reduced when antibody effector functions were impaired, with no antibody mediating antibody-dependent complement-induced lysis. These data suggest that antibodies binding multiple pertactin epitopes protect primarily by the same bactericidal mechanism, which overshadows contributions from blockade of other pertactin functions. These antibodies expand the available tools to further dissect pertactin''s role in infection and understand the impact of antipertactin antibodies on bacterial fitness. 相似文献
93.
Doxorubicin (DOX) and vincristine (VC) are anti-cancer drugs commonly used for lymphoma in veterinary and human medicine. However, there are several side effects caused by these drugs. In this study, the protective effects of sonicated Bordetella bronchiseptica bacterin (sBb) on dendritic cells (DCs) damaged by two anti-cancer drugs were investigated. DCs play important roles in the innate and adaptive immunity of hosts, especially activating T cells that can suppress tumor growth. The metabolic activity of DCs significantly increased after the treatment with sBb compared to that of control DCs. In addition, there was a marked change in mitochondrial integrity between DOX-treated DC and DOX + sBb-treated DCs. Flow cytometric analysis also demonstrated that sBb upregulated the expression of the surface markers of DCs, particularly CD54. In mixed lymphocyte responses, sBb significantly increased the antigen-presenting capability of DCs. In particular, sBb increased the capability of control DCs by approximately 150% and that of VC-treated DCs by 221%. These results suggest that sBb can be used as a potential immunostimulatory agent to protect DCs from anti-cancer drug-induced damage and provide fundamental information about using a combination of DCs and vincristine in immunotherapy. 相似文献
94.
Protective effects of anti-Bordetella pertussis adenylate cyclase antibodies against lethal respiratory infection of the mouse 总被引:1,自引:0,他引:1
95.
Sylvie Lenin Jean Michel Alonso Colette Brezin Murielle Rocancourt Olivier Poupel 《FEMS microbiology letters》1986,37(1):89-94
Abstract Adherence of B. pertussis to NIH3T3 mouse fibroblasts was efficiently inhibited by a mouse immune serum reacting specifically with the filamentous haemagglutinin (FHA), whereas a mouse immune serum reacting specifically with the pertussis toxin (Ptx) produced partial inhibition only significant after 3 h infection. Protection against cytopathic effects on infected 3T3 cells with anti-FHA antibodies was at least as effective (83.3%± 7.5) as with anti-Ptx antibodies (75%± 4). This suggests that adherence of B. pertussis to eukaryotic receptors is a primary mechanism determining both bacterial proliferation and toxic effects in susceptible cells, and that prevention of B. pertussis attachment to cell receptors might be sufficient to protect against both infectious and toxic processes in whooping cough. 相似文献
96.
Nicholas P West John T Fitter Ute Jakubzik Manfred Rohde Carlos A Guzmán Mark J Walker 《FEMS microbiology letters》1997,146(2):263-269
Non-motile mutants of Bordetella bronchiseptica were generated after mini-transposon mutagenesis. One non-motile mutant (designated VMM1) was derived from the bvg-positive strain BB7865 and four mutants (designated AMM1–4) were derived from the isogenic bvg-negative strain BB7866. Southern hybridisation analysis indicated that loss of motility was not due to the disruption of the flagellin subunit gene. Western blot and transmission electron microscopic analysis indicated that three of the five mutants expressed neither the flagellin subunit (40 kDa) nor flagella whereas one mutant expressed intact flagella under all conditions tested. One unique bvg-negative mutant, AMM4, exhibited temperature-dependent repression of flagella biosynthesis and motility at 37°C. The ability of AMM4 to invade and survive in HeLa cells was significantly decreased. 相似文献
97.
Growth and siderophore production by Bordetella pertussis under iron-restricted conditions 总被引:9,自引:0,他引:9
It has been demonstrated that under iron-restricted conditions Bordetella pertussis can obtain iron from iron-saturated human transferrin. Direct contact between B. pertussis and transferrin was not required as B. pertussis was able to acquire iron from transferrin when they were separated by a dialysis membrane. Siderophore activity was detected in supernatants from iron-restricted cultures of B. pertussis, B. bronchiseptica and B. parapertussis. Siderophores were identified as hydroxamates and were produced by both virulent and avirulent strains of B. pertussis. 相似文献
98.
[目的]产顺式环氧琥珀酸水解酶(CESH)新型菌株的筛选、鉴定及其产酶条件优化.[方法]通过电镜、Biolog GN、(G C)含量和16S rDNA序列研究,对筛选菌株进行分类鉴定.通过红外光谱、核磁共振氢谱和碳谱、质谱以及旋光度实验,鉴定纯化产物的结构并优化CESH产酶条件.[结果]本文筛选出一株产CESH的新型菌株,该菌株可将顺式琥珀酸盐转化为D(-)-酒石酸,属于博德特氏菌属,并将其命名为博德特氏菌BK-52.最佳发酵条件为:最佳温度30℃,最佳pH7.0,最佳发酵时间36 h,最佳碳源蔗糖,最佳无机氮源硫酸铵,最佳酶诱导剂顺式环氧琥珀酸二钠.在此最佳条件下,CESH酶活最高达764 U/g生物量.[结论]本文筛选的新菌株博德特氏菌BK-52为D(一)一酒石酸的生产提供了一种新的方法. 相似文献
99.
Protective effects of in vivo‐expressed autotransporters against Bordetella pertussis infection 下载免费PDF全文
Koichiro Suzuki Naoaki Shinzawa Keisuke Ishigaki Keiji Nakamura Hiroyuki Abe Aya Fukui‐Miyazaki Kazuyoshi Ikuta Yasuhiko Horiguchi 《Microbiology and immunology》2017,61(9):371-379
100.
Masaaki Nagai Masahiko Endoh Drusilla L. Burns Yasukiyo Nakase 《FEMS microbiology letters》1992,93(2):133-137
The effect of Bordetella heat-labile toxin (HLT) on cultured vascular or tracheal smooth cells labeled with [14C]arachidonic acid for 3 h was examined. At 37 degrees C, in the presence of Ca2+, HLT induced the release of radioactive substances from the cells in a dose-dependent manner but HLT had no effect on release of radioactivity from cells at 0 degrees C or in the absence of Ca2+. After cells were exposed to HLT, a 2-h lag period occurred before release of radioactivity was detected. The substances released from cells by HLT were identified as arachidonic acid and phosphatidylcholine. 相似文献