Matching Items (12)
Filtering by

Clear all filters

136975-Thumbnail Image.png
Description
Dengue virus infects millions of people every year. Yet there is still no vaccine available to prevent it. Here we use a neutralizing epitope determinant on the dengue envelope (E) protein as an immunogen to be vectored by a measles virus (MV) vaccine. However the domain III (DIII) of the

Dengue virus infects millions of people every year. Yet there is still no vaccine available to prevent it. Here we use a neutralizing epitope determinant on the dengue envelope (E) protein as an immunogen to be vectored by a measles virus (MV) vaccine. However the domain III (DIII) of the dengue 2 E protein is too small to be immunogenic by itself. In order for it to be displayed on a larger particle, it was inserted into the amino terminus of small hepatitis B surface antigen (HBsAg, S) coding sequence. To generate the recombinant MV vector and verify the efficiency of this concept, a reverse genetics system was used where the MV vectors express one or two additional transcription units to direct the assembly of hybrid HBsAg particles. Two types of recombinant measles virus were produced: pB(+)MVvac2(DIII-S,S)P and pB(+)MVvac2(DIII-S)N. Virus recovered from pB(+)MVvac2(DIII-S,S)P was viable. An ELISA assay was performed to demonstrate the expression and secretion of HBsAg. Supernatant from MVvac2(DIII-S,S)P infected cells confirmed that hybrid HBsAg-domain III particles with a density similar to traditional HBsAg particles were released. Characteristics of the subviral particle have been analyzed for the successful incorporation of domain III. The replication fitness of the recombinant MV was evaluated using multi-step growth kinetics and showed reduced replication fitness when compared to the parental strain MVvac2. This demonstrates that viral replication is hindered by the addition of the two inserts into MV genome. Further analysis of MVvac2(DIII-S)N is needed to justify immune response studies in a small animal model using both of the generated recombinant vectors.
ContributorsHarahap, Indira Saridewi (Author) / Reyes del Valle, Jorge (Thesis director) / Hogue, Brenda (Committee member) / Misra, Rajeev (Committee member) / Barrett, The Honors College (Contributor) / T. Denny Sanford School of Social and Family Dynamics (Contributor) / School of Human Evolution and Social Change (Contributor) / School of Life Sciences (Contributor)
Created2014-05
134344-Thumbnail Image.png
Description
Bee communities form the keystone of many ecosystems through their pollination services. They are dynamic and often subject to significant changes due to several different factors such as climate, urban development, and other anthropogenic disturbances. As a result, the world has been experiencing a decline in bee diversity and abundance,

Bee communities form the keystone of many ecosystems through their pollination services. They are dynamic and often subject to significant changes due to several different factors such as climate, urban development, and other anthropogenic disturbances. As a result, the world has been experiencing a decline in bee diversity and abundance, which can have detrimental effects in the ecosystems they inhabit. One of the largest factors that impacts bees in today's world is the rapid urbanization of our planet, and it impacts the bee community in mixed ways. Not very much is understood about the bee communities that exist in urban habitats, but as urbanization is inevitably going to continue, knowledge on bee communities will need to strengthen. This study aims to determine the levels of variance in bee communities, considering multiple variables that bee communities can differ in. The following three questions are posed: do bee communities that are spatially separated differ significantly? Do bee communities that are separated by seasons differ significantly? Do bee communities that are separated temporally (by year, interannually) differ significantly? The procedure to conduct this experiment consists of netting and trapping bees at two sites at various times using the same methods. The data is then statistically analyzed for differences in abundance, richness, diversity, and species composition. After performing the various statistical analyses, it has been discovered that bee communities that are spatially separated, seasonally separated, or interannually separated do not differ significantly when it comes to abundance and richness. Spatially separated bee communities and interannually separated bee communities show a moderate level of dissimilarity in their species composition, while seasonally separated bee communities show a greater level of dissimilarity in species composition. Finally, seasonally separated bee communities demonstrate the greatest disparity of bee diversity, while interannually separated bee communities show the least disparity of bee diversity. This study was conducted over the time span of two years, and while the levels of variance of an urban area between these variables were determined, further variance studies of greater length or larger areas should be conducted to increase the currently limited knowledge of bee communities in urban areas. Additional studies on precipitation amounts and their effects on bee communities should be conducted, and studies from other regions should be taken into consideration while attempting to understand what is likely the most environmentally significant group of insects.
ContributorsPhan, James Thien (Author) / Sweat, Ken (Thesis director) / Foltz-Sweat, Jennifer (Committee member) / School of Music (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Measles and mumps are highly contagious, vaccine-preventable diseases with cases continuing to persist in high two-dose vaccinated populations. Recent outbreaks on university and college campuses across the United States prompt a need for further understanding of the immunity levels afforded by the MMR vaccine which has significantly decreased incidence rates

Measles and mumps are highly contagious, vaccine-preventable diseases with cases continuing to persist in high two-dose vaccinated populations. Recent outbreaks on university and college campuses across the United States prompt a need for further understanding of the immunity levels afforded by the MMR vaccine which has significantly decreased incidence rates of measles and mumps since it was introduced.
Current methods for IgG antibody detection include enzyme immunoassays (EIA) such as the commercially available Diamedix Immunosimplicity® Measles IgG test kit and the Diamedix Immunosimplicity® Mumps IgG test kit. EIAs generally provide high sensitivity and strong specificity, however, there is a need for rapid screening of measles and mumps specific immunity in outbreak and resource-limited areas which could be solved by use a point-of-care (POC) platform.
This study aims to optimize a point-of-care device for the multiplexed detection of MeV, MuV, and RuV IgG antibodies in sera and to compare the sensitivity to commercial enzyme immunoassays. The IgG antibody levels to MeV and MuV were measured using EIA test kits for a total of 44 healthy serum samples. Of the samples, 6% were seronegative for MeV-specific IgG antibodies and 75% were seronegative for MuV-specific antibodies, showing low correlation of IgG antibody levels between both viruses.
To improve the sensitivity of the POC device, multiple conjugated fluorescent secondary antibodies were tested with different surface chemistries. Signal detection was measured using the pre-developed four-site slide reader. Preliminary data show that Nile Red microspheres provide robust signal detection and should be the secondary antibody of choice when sera are tested for IgG antibodies using the POC platform in future work.
ContributorsBharaj, Tirinder K. (Author) / Anderson, Karen (Thesis director) / Green, Alexander (Committee member) / Ewaisha, Radwa (Committee member) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
134876-Thumbnail Image.png
Description
PD-L1 blockade has shown recent success in cancer therapy and cancer vaccine regimens. One approach for anti-PD-L1 antibodies has been their application as adjuvants for cancer vaccines. Given the disadvantages of such antibodies, including long half-life and adverse events related to their use, a novel strategy using synbodies in place

PD-L1 blockade has shown recent success in cancer therapy and cancer vaccine regimens. One approach for anti-PD-L1 antibodies has been their application as adjuvants for cancer vaccines. Given the disadvantages of such antibodies, including long half-life and adverse events related to their use, a novel strategy using synbodies in place of antibodies can be tested. Synbodies offer a variety of advantages, including shorter half-life, smaller size, and cheaper cost. Peptides that could bind PD-L1 were identified via peptide arrays and used to construct synbodies. These synbodies were tested with inhibition ELISA assays, SPR, and pull down assays. Additional flow cytometry analysis was done to determine the binding specificity of the synbodies to PD-L1 and the ability of those synbodies to inhibit the PD-L1/PD-1 interaction. Although analysis of permeabilized cells expressing PD-L1 indicated that the synbodies could successfully bind PD-L1, those results were not replicated in non-permeabilized cells. Further assays suggested that the binding of the synbodies was non-specific. Other tests were done to see if the synbodies could inhibit the PD-1/PD-L1 interaction. This assay did not yield any conclusive results and further experimentation is needed to determine the efficacy of the synbodies in inhibiting this interaction.
ContributorsMujahed, Tala (Author) / Johnston, Stephen (Thesis director) / Blattman, Joseph (Committee member) / Diehnelt, Chris (Committee member) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
135487-Thumbnail Image.png
Description
The college textbook is the most commonly required component of almost any college course, regardless of a student's academic discipline. Professors often expect students to have access to the textbook and to use it to complete assigned readings. Textbooks often contain features that are designed to facilitate active reading, or

The college textbook is the most commonly required component of almost any college course, regardless of a student's academic discipline. Professors often expect students to have access to the textbook and to use it to complete assigned readings. Textbooks often contain features that are designed to facilitate active reading, or critical engagement with the information being read, to enhance learning of the material. However, students often do not read or prioritize reading the textbook. Students who do read, tend not to read the textbook as intended or use many of the features designed to promote active reading and enhanced learning of the material. Educational studies of textbooks tend to focus on aspects related to topics more relevant to publishers or professors with less research on aspects of the textbook applicable to students at the college level. The purpose of this study is to evaluate students' textbook use and their attitudes toward the textbook in an introductory biology course. Results of this study indicate students hold positive attitudes toward their textbook in an introductory biology course and majority of students do not use components meant to facilitate active learning. Although students report completing assigned readings, students may actually be reading select portions of what is assigned in using the textbook to prepare for exams. These results suggest that students may only be using their textbook to enhance their understanding of materials they expect to be tested on. The findings of this study help to understand the role of the textbook from the perspective of the student and provide insight for improving textbook design and use in science courses at the college level.
ContributorsRudolph, Alexia Marion (Author) / Vanmali, Binaben (Thesis director) / Chen, Ying-Chih (Committee member) / Yoho, Rachel (Committee member) / Department of Psychology (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
148192-Thumbnail Image.png
Description

Lyme disease is a common tick-borne illness caused by the Gram-negative bacterium Borrelia burgdorferi. An outer membrane protein of Borrelia burgdorferi, P66, has been suggested as a possible target for Lyme disease treatments. However, a lack of structural information available for P66 has hindered attempts to design medications to target

Lyme disease is a common tick-borne illness caused by the Gram-negative bacterium Borrelia burgdorferi. An outer membrane protein of Borrelia burgdorferi, P66, has been suggested as a possible target for Lyme disease treatments. However, a lack of structural information available for P66 has hindered attempts to design medications to target the protein. Therefore, this study attempted to find methods for expressing and purifying P66 in quantities that can be used for structural studies. It was found that by using the PelB signal sequence, His-tagged P66 could be directed to the outer membrane of Escherichia coli, as confirmed by an anti-His Western blot. Further attempts to optimize P66 expression in the outer membrane were made, pending verification via Western blotting. The ability to direct P66 to the outer membrane using the PelB signal sequence is a promising first step in determining the overall structure of P66, but further work is needed before P66 is ready for large-scale purification for structural studies.

ContributorsRamirez, Christopher Nicholas (Author) / Fromme, Petra (Thesis director) / Hansen, Debra (Committee member) / Department of Physics (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
147652-Thumbnail Image.png
Description

DNA nanotechnology is ideally suited for numerous applications from the crystallization and solution of macromolecular structures to the targeted delivery of therapeutic molecules. The foundational goal of structural DNA nanotechnology was the development of a lattice to host proteins for crystal structure solution. To further progress towards this goal, 36

DNA nanotechnology is ideally suited for numerous applications from the crystallization and solution of macromolecular structures to the targeted delivery of therapeutic molecules. The foundational goal of structural DNA nanotechnology was the development of a lattice to host proteins for crystal structure solution. To further progress towards this goal, 36 unique four-armed DNA junctions were designed and crystallized for eventual solution of their 3D structures. While most of these junctions produced macroscale crystals which diffracted successfully, several prevented crystallization. Previous results used a fixed isomer and subsequent investigations adopted an alternate isomer to investigate the impact of these small sequence changes on the stability and structural properties of these crystals. DNA nanotechnology has also shown promise for a variety biomedical applications. In particular, DNA origami has been demonstrated as a promising tool for targeted and efficient delivery of drugs and vaccines due to their programmability and addressability to suit a variety of therapeutic cargo and biological functions. To this end, a previously designed DNA barrel nanostructure with a unique multimerizable pegboard architecture has been constructed and characterized via TEM for later evaluation of its stability under biological conditions for use in the targeted delivery of cargo, including CRISPR-containing adeno-associated viruses (AAVs) and mRNA.

ContributorsHostal, Anna Elizabeth (Author) / Anderson, Karen (Thesis director) / Stephanopoulos, Nicholas (Committee member) / Yan, Hao (Committee member) / School of Life Sciences (Contributor) / School of Molecular Sciences (Contributor) / School of International Letters and Cultures (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
161214-Thumbnail Image.png
Description

Sulfur oxidation is a process that is seen a wide variety of places. One particular place is Yellowstone national park where an abundance of hot springs are present. These acidic and hot places are prime locations for sulfur oxidation to occur. At a very basic level this is thought of

Sulfur oxidation is a process that is seen a wide variety of places. One particular place is Yellowstone national park where an abundance of hot springs are present. These acidic and hot places are prime locations for sulfur oxidation to occur. At a very basic level this is thought of as Sulfur, oxygen, and water forming sulfate and hydrogen. Many other reactions occur when an organism performs these processes, and many enzymes are used for this. This paper aimed to create, balance, and analyze the reactions involved in the paper Sulfur Oxidation in the Acidophilic Autotrophic Acidithiobacillus spp. (Wang et al., 2019) Once these reactions were balanced thermodynamic properties were found to evaluate the Gibbs Free Energy of these reactions. This allowed for a unique energy-based view of how this web of reactions relate to each other.

ContributorsMolina, Johnathan (Author) / Shock, Everett (Thesis director) / Weeks, Katelyn (Committee member) / Barrett, The Honors College (Contributor) / School of Molecular Sciences (Contributor)
Created2021-12
Description

Memory CD8+ T cells protect against secondary viral infections. They develop and maintain exclusively in circulation (e.g. central memory - Tcm) or are excluded from re-circulation (resident memory - Trm). The extracellular ATP receptor P2RX7 promotes both Tcm and Trm generation. High (P2RX7hi) P2RX7-expressing early effector cells show survival, memory

Memory CD8+ T cells protect against secondary viral infections. They develop and maintain exclusively in circulation (e.g. central memory - Tcm) or are excluded from re-circulation (resident memory - Trm). The extracellular ATP receptor P2RX7 promotes both Tcm and Trm generation. High (P2RX7hi) P2RX7-expressing early effector cells show survival, memory and pluripotency genes. Conversely, many terminal effector (TE) and apoptosis genes are upregulated in low (P2RX7lo) P2RX7-expressing cells. Among these genes is the zinc-finger transcriptional repressor Zeb2, which promotes TE differentiation at the expense of the memory cell pool. Given that Zeb2 was higher in P2RX7lo early effector cells, we postulated that Zeb2 ablation would allow P2RX7-deficient CD8+ T cells to skew towards memory subsets. To test this, we used RNP-based CRISPR-Cas9 to knockout Zeb2 in wild type or P2RX7-deficient P14 cells. At the memory timepoint, Zeb2 ablation led to a rescue of the ability of P2RX7-deficient cells to differentiate into the CD62L+ Tcm and CD69hiCD103hi Trm subsets, as well as increase the population of each. Our data suggest that P2RX7 imprints a pro-memory signature that is, to some extent, dependent on the negative regulation of Zeb2.

ContributorsVan Dijk, Sarah (Author) / Holechek, Susan (Thesis director) / Borges da Silvs, Henrique (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / School of Molecular Sciences (Contributor) / School of International Letters and Cultures (Contributor)
Created2021-12
161062-Thumbnail Image.png
Description

Early detection of disease is essential for alleviating disease burden, increasing success rate and decreasing mortality rate especially for cancer. To improve disease diagnostics, many candidate biomarkers have been suggested using molecular biology or image analysis techniques over the past decade. The receiver operating characteristics (ROC) curve is a standard

Early detection of disease is essential for alleviating disease burden, increasing success rate and decreasing mortality rate especially for cancer. To improve disease diagnostics, many candidate biomarkers have been suggested using molecular biology or image analysis techniques over the past decade. The receiver operating characteristics (ROC) curve is a standard technique to evaluate a diagnostic accuracy of biomarkers, but it has some limitations especially for heterogeneous diseases. As an alternative of the ROC curve analysis, we suggest a jittered dot plot (JDP) and JDP-based evaluation measures, above mean difference (AMD) and averaged above mean difference (AAMD). We demonstrate how JDP and AMD or AAMD together better evaluate biomarkers than the standard ROC curve. We analyze real and heterogeneous basal-like breast cancer data.

ContributorsBrister, Danielle (Author) / Chung, Yunro (Thesis director) / Park, Jin (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / School of Molecular Sciences (Contributor) / School of International Letters and Cultures (Contributor) / School of Human Evolution & Social Change (Contributor)
Created2021-12