• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >Development and assessment of an attenuated Rhodococcus equi oral vaccine that produces VapA.
【24h】

Development and assessment of an attenuated Rhodococcus equi oral vaccine that produces VapA.

机译：开发和评估产生VapA的减毒马红球菌口服疫苗。

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

This thesis is an investigation of the development of a safe and potentially efficacious attenuated strain of Rhodococcus equi for use in oral immunization of foals. Initial work involved the attempted development of a killed but metabolically active ("KMBA") strain of R. equi through use of two double crossover mutations in the uvrA and uvrB genes. The suicide vector for uvrA, pSuvrA, and the first two steps of a second sucide vector for uvrB were developed. A double crossover mutation in the uvrA gene of R. equi 103+ was not successfully obtained due to the presence of multiple homologous sites for insertion on the chromosome, therefore this approach was abandoned. The second approach involved expression of VapA in a live, virulence-plasmid negative strain ofR. equi (strain 103-), with assessment of virulence and immunogenicity in mice. PCR-amplified fragments of entire vapA gene with and without the upstream virulence-plasmid genes virR, orj5, vapH, orf7 and orf8 (orf4-8) were cloned into a shuttle vector pNBV1. These plasmids, named pAWVapA and pAW48A, were electroporated into strain 103-. The presence of the recombinant vectors in the attenuated strain (103-) and the integrity of the inserted genes were confirmed by antibiotic selection, PCR and DNA sequencing. SDS-PAGE and Western blotting showed that both constructs expressed VapA. The virulence for mice of the two recombinant R. equi was compared to that of wild type R. equi 103+ by intravenous inoculation of mice with the organisms and examination of liver clearance 4 days later. Mice inoculated with R. equi 103-, 103-/pAWVapA and 103-/pNBV1 completely cleared infection. Strain 103-/pAW48A persisted in 47% of the mice, whereas wild-type 103+ persisted in all treatment group mice. No detectable IgG to VapA was noted in any of the mice. R. equi was isolated from the feces of some mice after oral vaccination. No major granulomatous lesions were noted on histopathology in any mice and there was no significant difference in liver bacterial colonization in any of the groups challenged with R. equi 103+, showing that oral immunization of mice does not lead to effective immunization against this organism.
机译：本论文是对马齿红球菌安全且潜在有效的减毒菌株的开发的研究，该菌株可用于小马驹的口服免疫。最初的工作涉及通过在uvrA和uvrB基因中使用两个双重交叉突变，尝试开发一种被杀死的但代谢活跃的马鞭草（KMBA）菌株。开发了uvrA的自杀载体，pSuvrA，以及uvrB的第二种自杀载体的前两个步骤。由于在染色体上存在多个同源插入位点，因此未能成功获得马蹄疫杆菌103+的uvrA基因的双重交叉突变，因此放弃了这种方法。第二种方法涉及在活的，毒力质粒阴性的R株​​中表达VapA。 equi（菌株103-），评估小鼠的毒力和免疫原性。将具有和不具有上游毒力质粒基因virR，orj5，vapH，orf7和orf8（orf4-8）的PCR扩增的完整vapA基因片段克隆到穿梭载体pNBV1中。将这些名为pAWVapA和pAW48A的质粒电穿孔到菌株103-中。减毒菌株（103-）中重组载体的存在以及插入基因的完整性通过抗生素选择，PCR和DNA测序来证实。 SDS-PAGE和蛋白质印迹显示两种构建体均表达VapA。通过用生物体静脉内接种小鼠并在4天后检查肝清除率，将两种重组马齿。的小鼠的毒力与野生型马齿。的103+的毒力进行了比较。接种了马蹄疫杆菌103-，103- / pAWVapA和103- / pNBV1的小鼠完全清除了感染。 103- / pAW48A菌株在47％的小鼠中持续存在，而野生型103+在所有治疗组小鼠中持续存在。在任何小鼠中均未发现针对VapA的可检测IgG。口服疫苗后，从一些小鼠的粪便中分离出马齿.。在任何小鼠中，在组织病理学上均未发现主要的肉芽肿性病变，并且在用R. equi 103+攻击的任何组中，肝细菌定植均无显着差异，表明小鼠的口服免疫不会导致针对该生物体的有效免疫。

著录项

  • 作者

    Whitehead, Ashley Elizabeth.;

  • 作者单位

    University of Guelph (Canada).;

  • 授予单位 University of Guelph (Canada).;
  • 学科 Agriculture Animal Pathology.;Biology Veterinary Science.
  • 学位 D.V.Sc.
  • 年度 2010
  • 页码 153 p.
  • 总页数 153
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号