Matching Items (6)
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Description
Memory CD8+ T-cells can persist in the absence of antigen, primed for immediate activation and proliferation if later exposed to the same antigen. These cytotoxic lymphocytes provide long-term immunity following an acute infection. Studies have observed that intermediate levels of general T cell transfer prior to infection may cause an

Memory CD8+ T-cells can persist in the absence of antigen, primed for immediate activation and proliferation if later exposed to the same antigen. These cytotoxic lymphocytes provide long-term immunity following an acute infection. Studies have observed that intermediate levels of general T cell transfer prior to infection may cause an inappropriate response resulting in increased pathology rather than prevention. Therefore, our study focused on a memory CD8 T-cell therapy using lymphocytic choriomeningitis virus (LCMV) specific splenocytes, which activate and proliferate at an accelerated pace compared to that of naive T-cells. LCMV is a natural murine pathogen which also poses a zoonotic infection threat to humans, and the effect of immune cell vaccination therapies for LCMV is not fully understood. We observed the effect of multiple memory CD8 T cell dosage levels on overall disease and memory CD8 T-cell response to the virus. Infection by exposure to a carrier was shown to have a reduced impact on mice receiving higher doses of memory T cells prior to infection compared to mice receiving less or no memory cells. Higher presence of activated memory cells were shown to correlate with less disease-related weight loss and accelerated recovery times. Survival rate after exposure to carriers was not shown to be affected by dosage level, warranting further research regarding the prevalence of the immunopathology observed in other studies in natural murine transmission models.
ContributorsMiller, Charles (Author) / Blattman, Joseph (Thesis director) / Holechek, Susan (Committee member) / Carmen, Joshua (Committee member) / W. P. Carey School of Business (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
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Description
Cancer poses a significant burden on the global health system and represents a leading cause of death worldwide. For late-stage cancers, the traditional treatments of chemotherapy, radiation, and surgery are not always viable, and they can pose unnecessary health risks to the patients. New immunotherapies, such as adoptive cell transfer,

Cancer poses a significant burden on the global health system and represents a leading cause of death worldwide. For late-stage cancers, the traditional treatments of chemotherapy, radiation, and surgery are not always viable, and they can pose unnecessary health risks to the patients. New immunotherapies, such as adoptive cell transfer, are being developed and refined to treat such cancers. T cell immunotherapies in particular, where a patient’s T cell lymphocytes are isolated and amplified to be re-infused into the patient or where human cell lines are engineered to express T cell receptors for the recognition of common cancer antigens, are being expanded on because for some cancers, they could be the only option. Constructing an optimal pipeline for cloning and expression of antigen-specific TCRs has significant bearing on the efficacy of engineered cell lines for ACT. Adoptive T cell transfer, while making great strides, has to overcome a diverse T cell repertoire – cloning and expressing antigen-specific TCRs can mediate this understanding. Having identified the high frequency FluM1-specific TCR sequences in stimulated donor PBMCs, it was hypothesized that the antigen-specific TCR could be reconstructed via Gateway cloning methods and tested for expression and functionality. Establishing this pipeline would confirm an ability to properly pair and express the heterodimeric chains. In the context of downstream applications, neoantigens would be used to stimulate T cells, the α and β chains would be paired via single-cell or bulk methods, and instead of Gateway cloning, the CDR3 hypervariable regions α and β chains alone would be co-expressed using Golden Gate assembly methods.
ContributorsHirneise, Gabrielle Rachel (Author) / Anderson, Karen (Thesis director) / Mason, Hugh (Committee member) / Hariadi, Hugh (Committee member) / School of Life Sciences (Contributor, Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
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Description
Immunology, the study of the immune system and its ability to distinguish self from non-self, is a rapidly advancing sector of molecular biology. Cancer, being host derived, provides a difficult challenge for immune cells to distinguish it from normal tissue. The historic treatment of cancer has had three main methods:

Immunology, the study of the immune system and its ability to distinguish self from non-self, is a rapidly advancing sector of molecular biology. Cancer, being host derived, provides a difficult challenge for immune cells to distinguish it from normal tissue. The historic treatment of cancer has had three main methods: radiation, chemotherapy, and surgery (1). Due to recent advancements in understanding the regulatory role of adaptive immunity against cancer, researchers have been attempting to engineer therapies to enhance patients’ immunities against their cancer. Immunotherapies, both passive and active, demonstrate potential for combating many diseases. Passive immunization provides temporary protection against a pathogen, whereas active immunization teaches the patient’s system to respond to the antigen independently, giving life-long immunity. Passive immunization, generally, is a much more expensive method of providing immunity and is commonly used in emergency situations. Anti-venom, for example, uses antibodies grown in lab to neutralize venom. Examples of active immunization are vaccines, which mimic the wild-type pathogen in a way that elicits an immune response, specifically naïve lymphocyte activation and maturation into memory lymphocytes. In terms of cancer therapy, both passive and active immunization are being tested for efficacy (2).
ContributorsMarquardt, Charles Andrew (Author) / Anderson, Karen S. (Thesis director) / Mason, Hugh S. (Committee member) / Lake, Douglas F. (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Purinergic receptors sense extracellular nucleotide DAMPs such as ATP and adenosine, which are expressed in high concentrations in the tumor microenvironment (TME). A2AR, an adenosine receptor that is expressed on both T cells and tumor cells, promotes immunosuppression. However, the impact of the TME on changes in purinergic receptor expression

Purinergic receptors sense extracellular nucleotide DAMPs such as ATP and adenosine, which are expressed in high concentrations in the tumor microenvironment (TME). A2AR, an adenosine receptor that is expressed on both T cells and tumor cells, promotes immunosuppression. However, the impact of the TME on changes in purinergic receptor expression on CD8 T cells, as well as the overall dynamic between A2AR expression and tumor control, have not been clearly elucidated. Using in vitro co-culture experiments and in vivo murine tumor models, we found that A2AR is significantly upregulated on effector, tumor-infiltrating CD8 T cells. This upregulation was independent of the hypoxia, which we identified via inhibition of HIF1A. We found that this upregulation was partially dependent on CD8 T cell-tumor contact, but independent of cognate antigen recognition, by using transwell co-cultures, as well as combinations of different transgenic lines of CD8 T cells and tumor cells. We confirmed this observation in vivo using transfer of activated OTI cells into B16.OVA-bearing mice. Ultimately, we observed that the upregulation depended on inhibitory receptors such as Tim3 via the antibody blockade of Tim3. Using CRISPR/Cas9-mediated knockout of A2AR on activated CD8 T cells, we found that tumor-bearing mice receiving A2AR knockout CD8 T cells had increased tumor control. Taken together, these results suggest that inhibitory receptor-dependent, TCR-independent signals in the TME promotes upregulation of A2AR on CD8 T cells, leading to impairment of CD8 T cell-mediated tumor control.
ContributorsZhou, Maggie (Author) / Borges da Silva, Henrique (Thesis director) / Borges Florsheim, Esther (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / Economics Program in CLAS (Contributor)
Created2022-12
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Description
Computational models have long been used to describe and predict the outcome of complex immunological processes. The dissertation work described here centers on the construction of multiscale computational immunology models that derives biological insights at the population, systems, and atomistic levels. First, SARS-CoV-2 mortality is investigated through the lens of

Computational models have long been used to describe and predict the outcome of complex immunological processes. The dissertation work described here centers on the construction of multiscale computational immunology models that derives biological insights at the population, systems, and atomistic levels. First, SARS-CoV-2 mortality is investigated through the lens of the predicted robustness of CD8+ T cell responses in 23 different populations. The robustness of CD8+ T cell responses in a given population was modeled by predicting the efficiency of endemic MHC-I protein variants to present peptides derived from SARS-CoV-2 proteins to circulating T cells. To accomplish this task, an algorithm, called EnsembleMHC, was developed to predict viral peptides with a high probability of being recognized by CD T cells. It was discovered that there was significant variation in the efficiency of different MHC-I protein variants to present SARS-CoV-2 derived peptides, and countries enriched with variants with high presentation efficiency had significantly lower mortality rates. Second, a biophysics-based MHC-I peptide prediction algorithm was developed. The MHC-I protein is the most polymorphic protein in the human genome with polymorphisms in the peptide binding causing striking changes in the amino acid compositions, or binding motifs, of peptide species capable of stable binding. A deep learning model, coined HLA-Inception, was trained to predict peptide binding using only biophysical properties, namely electrostatic potential. HLA-Inception was shown to be extremely accurate and efficient at predicting peptide binding motifs and was used to determine the peptide binding motifs of 5,821 MHC-I protein variants. Finally, the impact of stalk glycosylations on NL63 protein dynamics was investigated. Previous data has shown that coronavirus crown glycans play an important role in immune evasion and receptor binding, however, little is known about the role of the stalk glycans. Through the integration of computational biology, experimental data, and physics-based simulations, the stalk glycans were shown to heavily influence the bending angle of spike protein, with a particular emphasis on the glycan at position 1242. Further investigation revealed that removal of the N1242 glycan significantly reduced infectivity, highlighting a new potential therapeutic target. Overall, these investigations and associated innovations in integrative modeling.
ContributorsWilson, Eric Andrew (Author) / Anderson, Karen (Thesis advisor) / Singharoy, Abhishek (Thesis advisor) / Woodbury, Neal (Committee member) / Sulc, Petr (Committee member) / Arizona State University (Publisher)
Created2022
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Description
The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic, declared in March 2020 resulted in an unprecedented scientific effort that led to the deployment in less than a year of several vaccines to prevent severe disease, hospitalizations, and death from coronavirus disease 2019 (COVID-19). Most vaccine models focus on the

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic, declared in March 2020 resulted in an unprecedented scientific effort that led to the deployment in less than a year of several vaccines to prevent severe disease, hospitalizations, and death from coronavirus disease 2019 (COVID-19). Most vaccine models focus on the production of neutralizing antibodies against the spike (S) to prevent infection. As the virus evolves, new variants emerge that evade neutralizing antibodies produced by natural infection and vaccination, while memory T cell responses are long-lasting and resilient to most of the changes found in variants of concern (VOC). Several lines of evidence support the study of T cell-mediated immunity in SARS-CoV-2 infections. First, T cell reactivity against SARS-CoV-2 is found in both (cluster of differentiation) CD4+ and CD8+ T cell compartments in asymptomatic, mild, and severe recovered COVID-19 patients. Second, an early and stronger CD8+ T cell response correlates with less severe COVID-19 disease [1-4]. Third, both CD4+ and CD8+ T cells that are reactive to SARS-CoV-2 viral antigens are found in healthy unexposed individuals suggesting that cross-reactive and conserved epitopes may be protective against infection. The current study is focused on the T cell-mediated response, with special attention to conserved, non-spike-cross-reactive epitopes that may be protective against SARS-CoV-2. The first chapter reviews the importance of epitope prediction in understanding the T cell-mediated responses to a pathogen. The second chapter centers on the validation of SARS-CoV-2 CD8+ T cell predicted peptides to find conserved, immunodominant, and immunoprevalent epitopes that can be incorporated into the next generation of vaccines against severe COVID-19 disease. The third chapter explores pre-existing immunity to SARS-CoV-2 in a pre-pandemic cohort and finds two highly immunogenic epitopes that are conserved among human common cold coronaviruses (HCoVs). To end, the fourth chapter explores the concept of T cell receptor (TCR) cross-reactivity by isolating SARS-CoV-2-reactive TCRs to elucidate the mechanisms of cross-reactivity to SARS-CoV-2 and other human coronaviruses (HCoVs).
ContributorsCarmona, Jacqueline (Author) / Anderson, Karen S (Thesis advisor) / Lake, Douglas (Thesis advisor) / Maley, Carlo (Committee member) / Mangone, Marco (Committee member) / LaBaer, Joshua (Committee member) / Arizona State University (Publisher)
Created2023