Nanoscale drug delivery systems have a great impact in current medical field. These carriers have the potential to improve the efficacy and reduce the toxicity of various medicinal products. A broad variety of different lipid based carriers had been developed and used as delivery systems in the past decades. This dissertation focused on the development of solid lipid nanoparticles (SLN) as delivery systems for a chemotherapeutic agent, docetaxel, and the use of liposomes as a carrier for recombinant protein vaccines. Docetaxel is a potent anticancer drug. However, there continues to be a need for alternative docetaxel delivery systems to improve its efficacy. Docetaxel nanoparticles comprised of lecithin as the main component were engineered using two methods, the emulsion precursor method and the solvent emulsification/evaporation method. Docetaxel in nanoparticles were more effective in killing tumor cells in culture than docetaxel solution. The intravenously injected docetaxel-nanoparticles increased the accumulation of docetaxel in tumors in mice. When administered by intravenous injection or oral routes, docetaxel-nanoparticles showed antitumor activity in tumor-bearing mice. The lecithin-based nanoparticles have the potential to be a novel biocompatible and efficacious delivery system for docetaxel. Liposomes, a well-known lipid based carrier, have been investigated extensively as a vaccine delivery system. The adjuvant activities of liposomes with different net surface charges (neutral, positive, or negative) were evaluated when simply admixed with protein antigens. Immunization study in mice after subcutaneously injection of different net charged liposomes showed different antibody responses, depending on the protein antigens. Antigens (OVA, PA) admixed with the negatively charged liposomes prepared with phospholipid, DOPA, induced a strong and functional antibody response comparable to the positively charged liposomes prepared with DOTAP lipid. The negatively charged DOPA liposomes admixed with OVA also induced OVA-specific CD8��� cytotoxic T lymphocyte responses and significantly delayed the growth of OVA-expressing B16-OVA melanoma in a mouse model. The adjuvant activity of the negatively charged liposomes may be related to the liposome's ability (i) to upregulate the expression of molecules related to the activation and maturation of antigen-presenting cells and (ii) to slightly facilitate the uptake of the antigens by antigen-presenting cells. Simply admixing certain negatively charged liposomes with certain protein antigens of interest may represent a novel platform for vaccine development. / Graduation date: 2012 / Access restricted to the OSU Community at author's request from Sept. 6, 2011 - Sept. 6, 2012

Influenza epidemics continue to cause morbidity and mortality within the human population despite widespread vaccination efforts. This, along with the ominous threat of an avian influenza pandemic (H5N1), demonstrates the need for a much improved, more sophisticated influenza vaccine. Our group has developed an in vitro model system for producing a membrane-bound Cytokine-bearing Influenza Vaccine (CYT-IVAC). Numerous cytokines are involved in directing both innate and adaptive immunity and it is our goal to utilize the properties of individual cytokines and other immunomodulatory proteins to create a more immunogenic vaccine. Here we report methodologies for the construction of membrane-bound cytokine fusion constructs in which our cytokine of interest (mouse GM-CSF, mouse IL-2, mouse IL-4) was fused to the membrane anchoring regions of viral Hemagglutinin (HA). Progeny virions, produced from influenza infected MDCK cells expressing membrane-bound cytokines, readily incorporated membrane-bound cytokines during budding and these cytokines on the virus particles retained bioactivity following viral inactivation. In vivo vaccination studies in mice showed enhanced antibody titers and improved protection following lethal challenge in those mice vaccinated with IL-2 and IL-4-bearing CYT-IVAC's compared to the conventional wild-type vaccine without membrane-bound cytokines. In addition, the immune response induced by IL-2 and IL-4-bearing CYT-IVACs was skewed toward Th1 (cellular) mediated immunity compared to the Th2 (humoral) dominated response induced with wild-type vaccination. Cellular mediated immunity afforded by IL-2 and IL-4 CYT-IVACs was manifested as enhanced influenza specific T cell proliferation and activation. In conclusion, we have developed a novel methodology to introduce bioactive membrane-bound cytokines directly into virus particles in order to augment the immunogenicity of inactivated, whole virus influenza vaccines. / Ph. D.

Synthetic CpG containing oligodeoxynucleotides (ODNs) are recognized by Toll like Receptor 9 (TLR9) and induce a strong pro-inflamatory immune response. To date, four different CpG ODN classes have been described. K-Class ODNs (also known as B-ODN) are potent B cell activators and stimulate TNF

<p>  </p> <p>The study presented within demonstrates that Nano-11, a plant-derived nanoparticle adjuvant, can be utilized in conjunction with innate immune stimulators, including the TLR3 agonist poly(I:C) and the STING agonist cyclic-di-AMP, to provoke enhanced immune responses when administered through intradermal vaccines. The study demonstrated that the utilization of a combination adjuvant consisting of Nano-11 and a synthetic STING agonist, ADU-S100, in intradermal vaccination exhibited dose-sparing characteristics and resulted in enhanced immunity in both mice and pigs when compared to intramuscular immunization. The utilization of Nano-11-based adjuvant technology has demonstrated both prophylactic and therapeutic efficacy in mouse models of lymphoma and melanoma. The proposed adjuvant platform for intradermal vaccines, which is based on Nano-11, aims to enhance the accessibility of vaccines for the purposes of controlling infectious diseases and cancers.</p>

<p>Polyacryl starch microparticles have been developed as an oral vaccine adjuvant capable of inducing strong local and systemic immune responses in mice. In this thesis, the starch microparticles were studied in order to increase basic understanding of their function. In particular, the thesis addressed aspects of the uptake of the particles and their presentation to the immune system after different routes of administration, in correlation with the differentiation of the induced immune response.</p><p>When using human serum albumin as a model antigen conjugated to the microparticles, it was found that the route of administration and the use of different combinations of routes, parenteral or oral, affect the profile (Th1/Th2 balance) of the induced immune response. It was also found that oral boosters are needed for the development of a local s-IgA response. </p><p>Ligated mouse intestinal loops in combination with confocal laser-scanning microscopy demonstrated that the uptake of the particles by the intestinal mucosa takes place over the follicle-associated epithelium (FAE) that covers the Peyer’s patches. The particles are also taken up in the villus epithelium when conjugated with rCTB, a ligand to the GM1 receptor. This qualitative difference in uptake did not affect the induced immune response. Thus, the addition of rCTB to the microparticles did not improve or influence the profile of the immune response. Chronic stress, known to alter the barrier function of the FAE, increased the cellular response but did not affect the humoral immune response. </p><p>Despite positive results in rodents, the particles were not able to boost a humoral immune response in man when tested with diphtheria toxin-cross reacting material (CRM197). Possible methods of improving the adjuvant effect in man are discussed.</p>

Polyacryl starch microparticles have been developed as an oral vaccine adjuvant capable of inducing strong local and systemic immune responses in mice. In this thesis, the starch microparticles were studied in order to increase basic understanding of their function. In particular, the thesis addressed aspects of the uptake of the particles and their presentation to the immune system after different routes of administration, in correlation with the differentiation of the induced immune response. When using human serum albumin as a model antigen conjugated to the microparticles, it was found that the route of administration and the use of different combinations of routes, parenteral or oral, affect the profile (Th1/Th2 balance) of the induced immune response. It was also found that oral boosters are needed for the development of a local s-IgA response. Ligated mouse intestinal loops in combination with confocal laser-scanning microscopy demonstrated that the uptake of the particles by the intestinal mucosa takes place over the follicle-associated epithelium (FAE) that covers the Peyer’s patches. The particles are also taken up in the villus epithelium when conjugated with rCTB, a ligand to the GM1 receptor. This qualitative difference in uptake did not affect the induced immune response. Thus, the addition of rCTB to the microparticles did not improve or influence the profile of the immune response. Chronic stress, known to alter the barrier function of the FAE, increased the cellular response but did not affect the humoral immune response. Despite positive results in rodents, the particles were not able to boost a humoral immune response in man when tested with diphtheria toxin-cross reacting material (CRM197). Possible methods of improving the adjuvant effect in man are discussed.

No description available.