Thesis (Ph. D.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 237-240). Also available on the World Wide Web.

Thesis (Ph. D., Natural Resources)--University of Idaho, December 2007. / Major professor: Kenneth D. Cain. Includes bibliographical references. Also available online (PDF file) by subscription or by purchasing the individual file.

Thesis (Ph. D.)--Washington State University, May 2010. / Title from PDF title page (viewed on June 4, 2010). "College of Veterinary Medicine." Includes bibliographical references.

Members of the family Chlamydiae cause a wide range of diseases. Chlamydia trachomatis and C. pneumoniae are most commonly associated with human disease. C. psittaci and C. pecorum are largely animal pathogens, although C. psittaci can cause pneumonia in the elderly and immunocompromised. A vaccine against these pathogens is desirable, but although multiple vaccine regimens have been examined, none have proven truly effective. Studies were conducted to evaluate the use of recombinant vaccinia virus (VV) vectors encoding chlamydial proteins as vaccine candidates using a guinea pig model. In the first study, guinea pigs were immunized with varying amounts of attenuated VV encoding either the M6 protein of Streptococcus pyogenes or chloramphenicol acetyl transferase (CAT) from E. coli. The purpose of this study was: (1) determine how much attenuated virus can be given intranasally to guinea pigs without causing death; (2) characterize the humoral and secretory antibody response to both the viral vector and M6 protein; and (3) develop a protocol for animal manipulation, and sample collection and storage for use in future research. The results obtained indicate that 10⁹ PFU of attenuated VV can be given intranasally to guinea pigs. Serum IgG was detected against VV proteins, as determined by immunoblotting. Antibodies against M6 could not be similarly detected in serum, or by direct enzyme linked immunosorbant assay (ELISA). IgG could not be detected by immunoblotting against either VV or M6 in saliva. The purpose of the second part of this research was to evaluate the potential efficacy of a vaccine using the C. psittaci guinea pig inclusion conjunctivitis (GPIC) strain proteins IncA and TroA. Guinea pigs were immunized intranasally with either PBS, control vaccinia virus, rVV:IncA, or rVV:TroA. Three weeks after immunization animals were challenged by ocular infection with C. psittaci elementary bodies (EBs). Eye swabs were taken following challenge and titered to determine the chlamydial load. Results indicate that rVV:TroA provides no protection against chlamydial challenge. Titers from rVV:IncA immunized animals appeared to be somewhat lower than those of the controls on day 4 post-challenge. This difference, however, proved not to be statistically significant. A single immunization with rVV:IncA or rVV:TroA was thus shown not lead to a protective immune response in guinea pigs under the conditions tested. / Graduation date: 2002

Thesis (Ph. D.)--University of Adelaide, Dept. of Microbiology and Immunology, 1988. / Includes bibliographical references (leaves 126-171).

No description available.

Thesis (Ph.D.) - University of Queensland, 2003. / Includes bibliography.

The spread of cholera is always associated with contaminated food or water and this is the reason this disease has been endemic in developing countries for centuries due to their lack of proper sanitation facilities and poor or no infrastructure for sewage systems. Cholera can spread quickly and sporadically after any natural disaster that destroys the sewage system or safe drinking water supply of both developed and undeveloped countries. In Southeast Asia in December 2004 and in Pakistan and Haiti 2010, cholera outbreaks followed the natural disasters; with most of the cholera victims being children. Although it is known that the best way to prevent cholera outbreak is the development of the infrastructure, provision of a safe drinking water supply and proper sanitation, this is a very long-term process, and most of the developing countries cannot afford such improvements. These situations can be made worse by natural disasters. Therefore there is a pressing need for the development of a cholera vaccine and there have been numerous research projects working towards this end for several decades. A few of them have been successful to date but because of the severe side effects and narrow range of protection, more effective and wider range vaccine development is still ongoing. In this study, crystallographic and enzymatic studies have been carried out on several novel proteins involved in the control of the production of the factors required for quorum sensing. Quorum sensing is a process in which bacterial cells communicate among themselves by the synthesis, release and detection of small chemical compounds called autoinducers. In this work, structural analysis was carried out on proteins involved in the synthesis and detection of the major autoinducer of Vibrio cholerae, named CAI-1. The crystal structure of CqsA involved in CAI-1 synthesis has been successfully solved and its enzymatic properties have been characterized. The structure of one domain of the cytoplasmic region of the CAI-1 receptor CqsS was also elucidated, and other domains were expressed. The crystal structure of another enzyme (VCA0859, an aldo-keto reductase) thought to have been involved in the synthesis of CAI-1 was also determined. Another protein named VCA0939 was also studied, due to its importance in biofilm development, and its ability to control quorum-sensing in an alternative pathway in the mutated version of pathogenic strains of V. cholerae that were responsible for the seventh cholera pandemic. The aim of this project was to understand the three dimensional structure of some proteins that are involved in quorum sensing and control of the expression of virulence genes for the pathogenesis of V. cholerae. Understanding the three dimensional structure of the proteins and the mode of autoinducer binding to its specific receptor could be highly valuable in the development of a chemical compound that could lead to the discovery of a novel drug with the ability to target cross species specification.

Most pathogens gain access to their host through mucosal surfaces. It is therefore desirable to develop mucosal vaccines that elicit an immune response to prevent this crucial first step in infection. Current mucosal vaccines are live attenuated strains of pathogens. More recent efforts have focused on the use of recombinant non-pathogenic gram-positive bacteria as live vaccine delivery vectors. Here I have tested the potential of Lactococcus lactis to be used as a vaccine vector. A recombinant strain of L. lactis has been constructed which expresses and displays on its surface the C repeat region (CRR) of the M6 protein of Streptococcus pyogenes. I show that nasal vaccination of mice with this strain elicited strong salivary IgA and serum lgG response. These responses protected mice against a nasal challenge with S. pyogenes. Subcutaneous vaccination with the same strain of L. lactis produced a strong serum lgG response, but no salivary lgA response. Subcutaneous vaccination did not protect the mice against nasal infections when the mice were challenged with S. pyogenes. The immune response and protection afforded by concomitant vaccination by both nasal and subcutaneous routes were better that that seen in nasal vaccination alone. This study shows that an effective vaccine against S. pyogenes is possible using L. lactis as a vaccine vector. It also opens up the potential of L. lactis to be used in the development of vaccines to other mucosal infections. / Graduation date: 2004

Dissertation (Ph.D.)--University of South Florida, 2007. / Includes vita. Includes bibliographical references. Also available online.