Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.

No description available.

published_or_final_version / Microbiology / Doctoral / Doctor of Philosophy

No description available.

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

Recent advances in DNA vaccine technology has brought about a promising strategy for the control of viruses that contain surface membrane glycoproteins. This type of vaccine involves the intramuscular injection of a bacterial plasmid containing a gene encoding a viral protein. The strategy uses eukaryotic processing of the protein as would naturally occur during a viral infection. In this study, plasmid DNA encoding the glycoproteins of infectious hematopoietic necrosis virus (pcDNA3-IHNV-g), snakehead rhabdovirus (pcDNA3-SHRV-g), or spring viremia of carp virus (pcDNA3-SVCV-g) was injected into the skeletal muscle of rainbow trout fry. At 30 days post-vaccination, fish were challenged with IHNV. Protection against IHNV was observed among all DNA vaccinated groups. Fish injected with plasmid pcDNA3-IHNV-g, pcDNA3-SHRV-g, or pcDNA3-SVCV-g had relative survival rates of 93.2%, 98.3% and 94.9%, respectively. The mechanisms for the viral mediated resistance induced by these glycoprotein based DNA vaccines is unknown. A parallel study conducted by Dr. Carol Kim on the production of Mx proteins in these fish indicates that the observed protection might be a consequence of the stimulation of interferon. / Graduation date: 1999

Vaccination is one of the major achievements of modern medicine. As a result of vaccination, diseases such as polio and measles have been controlled and small pox has been eliminated. However, despite these successes there are still many diseases of microbial origin that cause tremendous suffering because there are no vaccines or the vaccines available are inadequate. The development of DNA based vaccines and immunostimulatory CpG oligonucleotides (ODNs) as adjuvants offer new possibilities for developing new vaccines. The objectives of this research were to improve the delivery of polynucleotides and oligonucleotides to enhance their potency and to evaluate the feasibility of non-invasive methods for the delivery of vaccines through the skin in order to improve the safety and the ease of administration of human and veterinary vaccines. The results demonstrated that topical administration of plasmids in a lipid-based delivery system (biphasic lipid vesicles [Biphasix]) resulted in gene expression in the draining lymph nodes, as well as induction of antigen specific immune responses in mice. The use of electroporation significantly enhanced both gene expression and immune responses to DNA vaccines in pigs. Prior treatment with electroporation enhanced immune responses to both protein and DNA vaccines indicating that both gene expression and tissue damage are important mechanisms that electroporation uses to enhance immune responses. In addition, the formulation of CpG ODNs in biphasic lipid vesicles (BiphasixTM) called Vaccine-Targeting Adjuvant (VTA) enhanced immune response to protein antigens following systemic and mucosal administration.

Vaccination is one of the major achievements of modern medicine. As a result of vaccination, diseases such as polio and measles have been controlled and small pox has been eliminated. However, despite these successes there are still many diseases of microbial origin that cause tremendous suffering because there are no vaccines or the vaccines available are inadequate. The development of DNA based vaccines and immunostimulatory CpG oligonucleotides (ODNs) as adjuvants offer new possibilities for developing new vaccines. The objectives of this research were to improve the delivery of polynucleotides and oligonucleotides to enhance their potency and to evaluate the feasibility of non-invasive methods for the delivery of vaccines through the skin in order to improve the safety and the ease of administration of human and veterinary vaccines. The results demonstrated that topical administration of plasmids in a lipid-based delivery system (biphasic lipid vesicles [Biphasix]) resulted in gene expression in the draining lymph nodes, as well as induction of antigen specific immune responses in mice. The use of electroporation significantly enhanced both gene expression and immune responses to DNA vaccines in pigs. Prior treatment with electroporation enhanced immune responses to both protein and DNA vaccines indicating that both gene expression and tissue damage are important mechanisms that electroporation uses to enhance immune responses. In addition, the formulation of CpG ODNs in biphasic lipid vesicles (BiphasixTM) called Vaccine-Targeting Adjuvant (VTA) enhanced immune response to protein antigens following systemic and mucosal administration.

Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2003. / Includes bibliographical references (leaves 112-129). Also available in electronic version. Access restricted to campus users.

published_or_final_version / abstract / toc / Zoology / Master / Master of Philosophy