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Dysregulated ERK/MAPK Signaling in RASopathy Animal Model Systems Leads to a Decrease in mTOR Expression and Activation of Translational Machinery

Description

The RAS/MAPK (RAS/Mitogen Activated Protein Kinase) pathway is a highly conserved, canonical signaling cascade that is highly involved in cellular growth and proliferation as well as cell migration. As such, it plays an important role in development, specifically in development of the nervous system. Activation of ERK is indispensable for…

The RAS/MAPK (RAS/Mitogen Activated Protein Kinase) pathway is a highly conserved, canonical signaling cascade that is highly involved in cellular growth and proliferation as well as cell migration. As such, it plays an important role in development, specifically in development of the nervous system. Activation of ERK is indispensable for the differentiation of Embryonic Stem Cells (ESC) into neuronal precursors (Li z et al, 2006). ERK signaling has also shown to mediate Schwann cell myelination of the peripheral nervous system (PNS) as well as oligodendrocyte proliferation (Newbern et al, 2011). The class of developmental disorders that result in the dysregulation of RAS signaling are known as RASopathies. The molecular and cell-specific consequences of these various pathway mutations remain to be elucidated. While there is evidence for altered DNA transcription in RASopathies, there is little work examining the effects of the RASopathy-linked mutations on protein translation and post-translational modifications in vivo. RASopathies have phenotypic and molecular similarities to other disorders such as Fragile X Syndrome (FXS) and Tuberous Sclerosis (TSC) that show evidence of aberrant protein synthesis and affect related pathways. There are also well-defined downstream RAS pathway elements involved in translation. Additionally, aberrant corticospinal axon outgrowth has been observed in disease models of RASopathies (Xing et al, 2016). For these reasons, this present study examines a subset of proteins involved in translation and translational regulation in the context of RASopathy disease states. Results indicate that in both of the tested RASopathy model systems, there is altered mTOR expression. Additionally the loss of function model showed a decrease in rps6 activation. This data supports a role for the selective dysregulation of translational control elements in RASopathy models. This data also indicates that the primary candidate mechanism for control of altered translation in these modes is through the altered expression of mTOR.

ContributorsHilbert, Alexander Robert (Author) / Newbern, Jason (Thesis director) / Olive, M. Foster (Committee member) / Bjorklund, Reed (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)

Created2017-05

Plant-Expressed Vaccines: Enhancing the Recombinant Immune Complex Platform to Permit Rapid Vaccine Development Against Existing and Emerging Pathogens

Description

Vaccines are one of the most effective ways of combating infectious diseases and developing vaccine platforms that can be used to produce vaccines can greatly assist in combating global public health threats. This dissertation focuses on the development and pre-clinical testing of vaccine platforms that are highly immunogenic, easily modifiable,…

Vaccines are one of the most effective ways of combating infectious diseases and developing vaccine platforms that can be used to produce vaccines can greatly assist in combating global public health threats. This dissertation focuses on the development and pre-clinical testing of vaccine platforms that are highly immunogenic, easily modifiable, economically viable to produce, and stable. These criteria are met by the recombinant immune complex (RIC) universal vaccine platform when produced in plants. The RIC platform is modeled after naturally occurring immune complexes that form when an antibody, a component of the immune system that recognizes protein structures or sequences, binds to its specific antigen, a molecule that causes an immune response. In the RIC platform, a well-characterized antibody is linked via its heavy chain, to an antigen tagged with the antibody-specific epitope. The RIC antibody binds to the epitope tags on other RIC molecules and forms highly immunogenic complexes. My research has primarily focused on the optimization of the RIC platform. First, I altered the RIC platform to enable an N-terminal antigenic fusion instead of the previous C-terminal fusion strategy. This allowed the platform to be used with antigens that require an accessible N-terminus. A mouse immunization study with a model antigen showed that the fusion location, either N-terminal or C-terminal, did not impact the immune response. Next, I studied a synergistic response that was seen upon co-delivery of RIC with virus-like particles (VLP) and showed that the synergistic response could be produced with either N-terminal or C-terminal RIC co-delivered with VLP. Since RICs are inherently insoluble due to their ability to form complexes, I also examined ways to increase RIC solubility by characterizing a panel of modified RICs and antibody-fusions. The outcome was the identification of a modified RIC that had increased solubility while retaining high immunogenicity. Finally, I modified the RIC platform to contain multiple antigenic insertion sites and explored the use of bioinformatic tools to guide the design of a broadly protective vaccine.

ContributorsPardhe, Mary (Author) / Mason, Hugh S (Thesis advisor) / Chen, Qiang (Committee member) / Mor, Tsafrir (Committee member) / Wilson, Melissa (Committee member) / Arizona State University (Publisher)

Created2021

Perception of the Role of K-12 Schooling: Completing the Evaluative Loop for Sustainable Human Capacity Building Infrastructure (HCBI)

Description

This study examined perception of K12 schooling systems as experienced by a randomsample of adults in Phoenix, AZ. It explored whether the values purported as key factors in the American K12 schooling system - as presented in academic literature - were compatible with the lives, interests and goals of ‘users’, student-participants.…

This study examined perception of K12 schooling systems as experienced by a randomsample of adults in Phoenix, AZ. It explored whether the values purported as key factors in the American K12 schooling system - as presented in academic literature - were compatible with the lives, interests and goals of ‘users’, student-participants. In addition, it offered opportunity for post-K12 student-participants to share their views on the purposes, goals, and outcomes they held to be important. The sample consisted of 139 post-K12 stu- dents/individuals residing in Phoenix, AZ. Mean age of student-participants was 29. Results indicated a mismatch between purported K12 schooling goals and important outcomes embedded in the system and values held by the K12 student-participants. The participants in this research generally perceived K12 schooling as valuable, both to themselves and to society at large, but stressed that the deficiencies they perceived in the system were particular to delivery platforms as they relate to the learning styles of students and belonging. Future life skills and success - in and after K12 schooling - whether related to college or not were also of importance. Results revealed that the initial hypothesis of income, age, and ethnicity as key factors in satisfaction with K12 schooling was not borne-out. Rather it revealed that a sense of belonging and the suitability of learning platforms to the individual learning styles of students were of greatest significance.

ContributorsParker-Anderies, Margaret (Author) / Janssen, Marco (Thesis advisor) / Garcia, David (Committee member) / Mishra, Punya (Committee member) / Arizona State University (Publisher)

Created2022

Development of Plant-Made Monoclonal Antibodies to Address the SARS-CoV-2 Pandemic

Description

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease 2019 (COVID-19) that emerged from a zoonotic host at the end of 2019 and caused a public health crisis. In this collection of studies, Nicotiana benthamiana plants are used to set the foundation for producing monoclonal…

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease 2019 (COVID-19) that emerged from a zoonotic host at the end of 2019 and caused a public health crisis. In this collection of studies, Nicotiana benthamiana plants are used to set the foundation for producing monoclonal antibodies (mAbs) with homogeneous glycosylation to neutralize SARS-CoV-2 and potentially address the immunopathology often observed with severe COVID-19. Specifically, a mAb against the human interleukin (IL)-6 receptor (sarilumab) was generated and evaluated in vitro for its potential to reduce IL-6 signaling that has been shown to be associated with more severe cases of COVID-19. Furthermore, multiple mAbs that bind to the receptor-binding domain (RBD) of SARS-CoV-2 and efficiently neutralize the virus were developed using plant-based expression. Several of these mAbs are from different classes of RBD-binding mAbs that have distinct binding sites from one another. Several mAbs from different classes showed synergy in neutralizing the ancestral strain of SARS-CoV-2 and a smaller subset showed synergy when tested against the highly mutated Omicron (B.1.1.529) variant. Of interest, a novel RBD-binding mAb, termed 11D7, that was raised against the ancestral strain and derived from a hybridoma, appears to have an epitope on the RBD that contributes more synergy to a mAb combination that efficiently neutralizes the B.1.1.529 variant of SARS-CoV-2. This epitope was partially mapped by competitive binding and shows that it overlaps with another known antibody that binds a cryptic, distal epitope, away from the receptor binding site, giving insight into the potential mechanism by which 11D7 neutralizes SARS-CoV-2, as well as potentially allowing it to resist SARS-CoV-2 immune evasion more efficiently. Furthermore, this mAb carries a highly homogeneous glycan pattern when expressed in N. benthamiana, that may contribute to enhanced effector function and provides a tool to elucidate the precise role of crystallizable fragment (Fc)-mediated protection in SARS-CoV-2 infection. Ultimately, these studies provide evidence of the utility of plant-made mAbs to be used as cocktail members, giving clarity to the use of less potent mAbs as valuable cocktail components which will spur further investigations into how mAbs with unique epitopes work together to efficiently neutralize SARS-CoV-2.

ContributorsJugler, Collin (Author) / Chen, Qiang (Thesis advisor) / Lake, Douglas (Committee member) / Steele, Kelly (Committee member) / Mason, Hugh (Committee member) / Arizona State University (Publisher)

Created2022

Exploration of Aggregation and Multivalency as Viral Inhibition Strategies

Description

Scientists are entrusted with developing novel molecular strategies for effective prophylactic and therapeutic interventions. Antivirals are indispensable tools that can be targeted at viral domains directly or at cellular domains indirectly to obstruct viral infections and reduce pathogenicity. Despite their transformative potential in healthcare, to date, antivirals have been clinically…

Scientists are entrusted with developing novel molecular strategies for effective prophylactic and therapeutic interventions. Antivirals are indispensable tools that can be targeted at viral domains directly or at cellular domains indirectly to obstruct viral infections and reduce pathogenicity. Despite their transformative potential in healthcare, to date, antivirals have been clinically approved to treat only 10 out of the greater than 200 known pathogenic human viruses. Additionally, as obligate intracellular parasites, many virus functions are intimately coupled with host cellular processes. As such, the development of a clinically relevant antiviral is challenged by the limited number of clear targets per virus and necessitates an extensive insight into these molecular processes. Compounding this challenge, many viral pathogens have evolved to evade effective antivirals. Therefore, a means to develop virus- or strain-specific antivirals without detailed insight into each idiosyncratic biochemical mechanism may aid in the development of antivirals against a larger swath of pathogens. Such an approach will tremendously benefit from having the specific molecular recognition of viral species as the lowest barrier. Here, I modify a nanobody (anti-green fluorescent protein) that specifically recognizes non-essential epitopes (glycoprotein M-pHluorin chimera) presented on the extra virion surface of a virus (Pseudorabies virus strain 486). The nanobody switches from having no inhibitory properties (tested up to 50 μM) to ∼3 nM IC50 in in vitro infectivity assays using porcine kidney (PK15) cells. The nanobody modifications use highly reliable bioconjugation to a three-dimensional wireframe deoxyribonucleic acid (DNA) origami scaffold. Mechanistic studies suggest that inhibition is mediated by the DNA origami scaffold bound to the virus particle, which obstructs the internalization of the viruses into cells, and that inhibition is enhanced by avidity resulting from multivalent virus and scaffold interactions. The assembled nanostructures demonstrate negligible cytotoxicity (<10 nM) and sufficient stability, further supporting their therapeutic potential. If translatable to other viral species and epitopes, this approach may open a new strategy that leverages existing infrastructures – monoclonal antibody development, phage display, and in vitro evolution - for rapidly developing novel antivirals in vivo.

ContributorsPradhan, Swechchha (Author) / Hariadi, Rizal (Thesis advisor) / Hogue, Ian (Committee member) / Varsani, Arvind (Committee member) / Chen, Qiang (Committee member) / Arizona State University (Publisher)

Created2022

Supporting Conservation of Food, Energy, and Water Resources at Households: A Role-Playing Game Approach

Description

The consumption of food, energy, and water (FEW) resources in U.S. households is very carbon-intensive. However, these negative climate change impacts are often invisible due to insufficient awareness and knowledge. Serious games (SGs) can potentially address this issue through an experiential and rigorous approach to simulate household actions and impacts…

The consumption of food, energy, and water (FEW) resources in U.S. households is very carbon-intensive. However, these negative climate change impacts are often invisible due to insufficient awareness and knowledge. Serious games (SGs) can potentially address this issue through an experiential and rigorous approach to simulate household actions and impacts in a playful but realistic setting. This dissertation focuses on: (a) the design and testing of an SG called HomeRUN (Role-play for Understanding Nexus); (b) the effectiveness of gameplay in advancing player knowledge about the upfront costs, financial returns, and greenhouse gas (GHG) emissions of various household decisions; and (c) the effectiveness of intervention messages in increasing FEW conservation to reduce household GHG emissions. The results of gameplay sessions played by 150 university students show that HomeRUN is fun to play, creates a flow experience, and results in experiential learning. The majority of players agreed that the game experience will continue over time to influence their future consumption behaviors to conserve FEW resources. Female players tended to gain more knowledge about financial aspects of interventions, whereas male players were more likely to increase their understandings of GHG emissions and resource consumption after playing HomeRUN. Social comparison intervention messages about energy and food consumption led to the highest reductions in household carbon emissions. The messages associated with each FEW resource tended to be most likely to lead to FEW conservation actions with the game that most closely corresponded to the particular FEW resource addressed in the message. This dissertation advances understandings about the design and use of SGs to foster learning and promote sustainable household FEW consumption.

ContributorsHanif, Muhammad Adnan (Author) / Agusdinata, Datu Buyung (Thesis advisor) / Halvorsen, Kathleen (Committee member) / Janssen, Marco (Committee member) / Arizona State University (Publisher)

Created2021

Apelin Nanoparticle Patch Protects Mouse Heart From Myocardial Infarction-Associated Heart Failure

Description

Heart disease is the leading cause of death in the developed world and often occurs following myocardial infarction. Apelin is an endogenous prepropeptide that has been studied for its role in improving cardiac contractility and vasodilation but suffers from a short half-life in the body. By encasing apelin in a…

Heart disease is the leading cause of death in the developed world and often occurs following myocardial infarction. Apelin is an endogenous prepropeptide that has been studied for its role in improving cardiac contractility and vasodilation but suffers from a short half-life in the body. By encasing apelin in a nanoparticle patch, we were able to slowly release apelin to cardiac tissue and observe its effects for one month following induced myocardial infarction surgery in mice. This study demonstrates that the apelin nanoparticles can protect the heart from myocardial-induced heart failure, observing overall improved cardiac function and reduction of fibrotic scarring associated with post-myocardial infarction compared to a nontreated group.

ContributorsHenderson, Adam (Author) / Chen, Qiang (Thesis director) / Zhu, Wuqiang (Committee member) / Barrett, The Honors College (Contributor) / College of Health Solutions (Contributor)

Created2022-05

Addressing the Effects of Weight Stigma in the Medical System Using Weight-neutral Approaches to Patient Care

Description

Weight stigma is present in many aspects of society, and especially in medicine. Weight stigma has detrimental effects on individuals physical and mental health, as well as patient-physician interactions. Application of weight-neutral healthcare ideologies such as Health at Every Size (HAES) are promising ways of decreasing weight stigma within the…

Weight stigma is present in many aspects of society, and especially in medicine. Weight stigma has detrimental effects on individuals physical and mental health, as well as patient-physician interactions. Application of weight-neutral healthcare ideologies such as Health at Every Size (HAES) are promising ways of decreasing weight stigma within the medical field without reducing the focus on improving patient health. Most widely applicable interventions include changing the focus of interactions from weight to health-promoting behaviors and lab values, improving provider education, and improving the general population's awareness of the problem.

ContributorsBrouhard, Mya (Author) / Chen, Qiang (Thesis director) / Parker, Lynn (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / Department of Psychology (Contributor)

Created2024-05

Preprocedural Diet’s Effect on Efficacy of Platelet Rich Plasma Injections

Description

Platelet Rich Plasma (PRP) is an emerging procedure in regenerative medicine that offers a non-surgical minimally invasive way for tissue repair and regeneration. PRP has many different bioactive molecules that are able to influence and help achieve greater recovery and regenerative outcomes. Diet has many effects on platelets and looking…

Platelet Rich Plasma (PRP) is an emerging procedure in regenerative medicine that offers a non-surgical minimally invasive way for tissue repair and regeneration. PRP has many different bioactive molecules that are able to influence and help achieve greater recovery and regenerative outcomes. Diet has many effects on platelets and looking at the mechanism in which platelet function and aggregation are affected with different diets shows how they are able to affect PRP therapy. Looking at these mechanisms allows for better physician recommendations for preprocedural diets to optimize efficacy. This paper conducts a systematic review to investigate the influence that diet can have on PRP outcomes. It was shown that high fat diets lower the efficacy of treatment while the Mediterranean diet helps promote platelet function and help efficacy. The future is to look at more diets while also integrating lifestyle choice before treatment for optimal outcomes.

ContributorsLaguna, Sebastian (Author) / Chen, Qiang (Thesis director) / Goyle, Ashu (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / Dean, W.P. Carey School of Business (Contributor)

Created2024-05

Institutional Analysis of Stakeholder, Rightsholder, and Public Participation under NEPA: Procedural Justice in the Case of a Proposed Arizona Copper Mine

Description

Copper demand is surging in the U.S. and around the world as countries embrace new forms of energy to combat climate change. But copper mining – while a key strategy to address supply shortages – can serve as a vehicle for injustice by imposing socio-ecological burdens for nearby communities. Due…

Copper demand is surging in the U.S. and around the world as countries embrace new forms of energy to combat climate change. But copper mining – while a key strategy to address supply shortages – can serve as a vehicle for injustice by imposing socio-ecological burdens for nearby communities. Due to the growing demand for copper with resulting justice issues, more research is needed to evaluate governance for the mining sector using an environmental justice lens. The National Environmental Policy Act (NEPA) is a key environmental regulation that governs mining in the U.S. Therefore, I used a qualitative case study approach to examine how NEPA requirements shape engagement in public comment opportunities. I selected the Resolution Copper Mine as a case study because of its potential to support the energy transition but pose a significant dilemma for justice: the mine is anticipated to generate 25 percent of the U.S. copper demand each year but disturb lands that hold spiritual significance for Native American Tribes. I used the Institutional Analysis and Development (IAD) framework to analyze institutional dynamics and evaluate the NEPA process for public participation using a procedural justice lens. Drawing on interview data and document analysis, the results show that process rules such as a land exchange bill and the lengths of comment opportunities were among the key barriers for participation. Socioeconomic conditions of communities including access to social resources (i.e. access to internet and technical assistance) and institutional trust posed further barriers for participation. Hence, this study suggests that federal decision-makers should aim to better integrate procedural justice into the NEPA process.

ContributorsLewis, Sydney (Author) / Kellner, Elke (Thesis director) / Janssen, Marco (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)

Created2024-05