The ectodomain of influenza matrix protein 2 (M2e) may be an ideal candidate in the development of influenza universal vaccine due to its highly conserved property among different subtypes/strains of influenza virus. M2e based vaccines have been extensively studied and potent cross-subtype/strain protections have been reported. However, more and more M2e mutants of influenza virus have been identified in recent years. It is still unclear whether M2e based vaccines are effective against these M2e mutants of influenza virus. This study first evaluated cross-protection of an M2e tetrameric peptide vaccine based on H5N1 virus strain A/Vietnam/1194/04 (VN/1194-M2e) against lethal challenges of M2e mutants of H5N1 virus strain A/Hong Kong/156/97 (HK/156) and a novel H7N9 virus, because there are 3 or 5 amino acid differences between VN/1194-M2e and HK/156-M2e or VN/1194-M2e and H7N9-M2e. The results showed that the vaccination of VN/1194-M2e did not induce high level of cross-reactive antibodies against HK/156-M2e and just provided poor cross-protection against lethal challenge of HK/156 virus. In contrast, VN/1194-M2e vaccination induced high level of cross-reactive antibodies against H7N9-M2e. Consistently, the vaccination provided good cross-protection against lethal challenge of H7N9 virus. These results strongly suggested that some mutations in M2e, such as mutations at positions 10, 14 and 16 which found in HK/156 M2e, might affect the M2e vaccine efficacy, but some others, such as five mutations found in H7N9-M2e, might not be critical for the M2e immunogenicity. This study then investigated the relationship between the M2e immunogenicity and amino acid mutations of the M2e. Beside VN/1194-M2e (P0), we synthesized additional 10 M2e mutant peptides which contain different single or multiple mutations. The 3D structures of these M2e peptides were predicted and analyzed. The prediction results showed that group 1 peptides (P0, P10, P14, P16, P18, P20 and P18-20) exhibited either irregular structures or loose hairpin structures which might associate with well exposure of antigenic epitope, whereas group 2 peptides (P10-14, P10-16, P14-16 and P10-14-16) formed tight hairpin structures in which antigenic epitope might bury inside their own secondary structure. Vaccination efficacies of these M2e peptides were evaluated in mice for antibody responses and cross-protection against lethal challenge of VN/1194 and HK/156 viruses. Our results showed that vaccinations of group 1 peptides induced high levels of cross-reactive antibodies against VN/1194-M2e and good cross-protection against lethal challenge of VN/1194 virus. However, vaccinations of group 2 peptides vaccinations induced significantly lower VN/1194-M2e antibody responses and poor cross-protection against lethal challenge of VN/119 virus. Furthermore, both group 1 and group 2 peptides could just induce low levels of cross-reactive antibodies against HK/156-M2e and poor protection against lethal challenge of HK/156 virus. Although H5N1-M2e tetrameric peptide has been previously shown to protect mice from lethal challenges by different subtypes/strains of influenza virus, this study has shown that certain amino acid variations in M2e could weaken M2e immunogenicity but some others might not. The different secondary structures of M2es may probably associate with their immunogenicity. Our findings have provided valuable information for the development of M2e based universal vaccines. / published_or_final_version / Microbiology / Doctoral / Doctor of Philosophy

Title page, table of contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library. / The studies submitted for this thesis encompass two broad areas of interest. The first is the role of extracellular matrix during folliculogenesis, including ovulation and corpus luteum formation. The observations made were extended in a second series of studies investigating matrix and other parameters of morphologically distinct follicles. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1274421 / Thesis (Ph.D.) -- University of Adelaide, School of Paediatrics and Reproductive Health, 2007

Vascular smooth muscle cells (VSMC) in the healthy adult arterial wall are a highlydifferentiated cell type with low levels of proliferation. However, when activated these cells can undergo a phenotypic change to become proliferative, migratory and excrete higher levels of extra-cellular matrix. While this cellular change is an essential element of the adaptable vasculature, excessive proliferation of VSMC underpins the development of a number of disease states, including atherosclerosis and restenosis after balloon angioplasty. The activation of VSMC is dependent on intracellular signalling pathways broadly altering gene expression. A key feature of this process is the initial potent regulation of transcription factors such as Egr-1, c-Jun and Ets-1, which then drive further transcriptional changes resulting in phenotypic change. The aim of this thesis was to discover novel genes, particularly transcription factors, regulated early upon stimulation and to characterise their contribution to the activation of VSMC. A key stimulus for activation of VSMC is the release of fibroblast growth factor 2 (FGF-2). A microarray used to explore the effects of FGF-2 exposure demonstrated the extensive nature of transcriptional modulation. In addition, it highlighted a number of transcription factors that were not previously described in VSMC: p8, ATF-4 and SHARP-2. In particular, SHARP-2 was potently upregulated and was reconfirmed in animal models of vascular injury. The subsequent contribution these factors make to VSMC activation was also demonstrated. p8 strongly induced VSMC proliferation, while ATF-4 contributed to cytokine production and SHARP-2 potently downregulated VSMC differentiation markers. A second area that was explored related to a gene known as YRDC, which was found to be upregulated upon stimulation of VSMC. YRDC is highly conserved across almost all cellular life, however its function remains unknown. A number of novel splice variants of YRDC were discovered and demonstrated to be differentially regulated in VSMC upon stimulation. Further work to commence characterising its function showed that it interacts with key ribosomal proteins and most likely plays a role in regulating translation. The discovery of the relevance of these genes to vascular biology in addition to their transcriptional regulation makes an important contribution to increasing our understanding of the molecular mechanisms behind vascular remodelling.

Diss. (sammanfattning) Stockholm : Karol. inst., 2001. / Härtill 5 uppsatser.

Thesis (M.Sc.). / Written for the Dept. of Chemistry. Title from title page of PDF (viewed 2008/05/14). Includes bibliographical references.

Thesis (M.S.)--Villanova University, 2008. / Biology Dept. Includes bibliographical references.

Thesis (M.A.)--Kent State University, 2007. / Title from PDF t.p. (viewed July 3, 2008). Advisor: William J. Landis. Includes bibliographical references (p. 64-68).

Thesis (M.Sc.). / Written for the Dept. of Biology. Title from title page of PDF (viewed 2009/13/07). Includes bibliographical references.

Thesis (doctoral)--Lunds Universitet, 1994. / Added t.p. with thesis statement inserted. Includes bibliographical references.

Thesis (doctoral)--Uppsala University, 1983. / Includes bibliographical references (p. 29-40).