Other Immunology and Infectious Disease Commons^™

Mhc Class I Tyrosine Phosphorylation Site Y320 Augments Cd8+ T Cell Priming, Effector Function, And Memory Response, Yimo Sun, Gregory A Lizee, Yitao Tang, Priscilla Ortiz, R Eric Davis

Dissertations and Theses (Open Access)

The cytoplasmic domain of MHC class I (MHC-I) molecules contains a single, highly conserved tyrosine residue (Y320). In previous work, we found that mice expressing a Y320F-mutated form of H-2K^b had reduced capacity to generate K^b-restricted cytotoxic T lymphocyte (CTL) responses following viral infection, due (at least in part) to defects in endolysosomal trafficking of H-2K^b and antigen cross-presentation by dendritic cells (DCs). In this study, we investigated whether there are additional, post-presentation dependencies on Y320 for T-cell priming. We engineered both human- and mouse-derived antigen-presenting cells (APCs) to express either wild-type MHC-I or variants of …

Investigating Metabolic And Mitochondrial Adaptations Triggered By Blood Flow During The Endothelial-To-Hematopoietic Transition, Paulina Horton

Dissertations and Theses (Open Access)

Hematopoietic stem cell (HSC) transplant is the standard of care for many hematologic diseases. However, many patients cannot benefit from this potentially curative treatment because they cannot find a suitable donor, contributing to a high level of unmet need. Recently, bona fide HSCs capable of robust engraftment and differentiation have been generated from iPSCs utilizing wall shear stress (WSS) to help promote HSC generation. However, the mechanisms through which WSS regulates hematopoiesis remain poorly understood. Scientists, therefore, continue to look for the mechanotransduction pathways that promote hematopoiesis, and key answers may lie in examining the role of extrinsic factors that …

Differential Progression Of Pancreatic Premalignancy In Geographically Distant Murine Transgenic Cohorts Uncovers Key Role Of Microbial Metabolites, Rian M. Howell

Dissertations and Theses (Open Access)

Cancer is a leading cause of death worldwide. Despite recent advances in diagnostic and therapeutic modalities, pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer that remains highly lethal. Efforts have been made to increase the understanding of the underlying mechanisms driving early stages of tumor development, when the cancer is most susceptible to intervention. To this end, genetically engineered mouse models (GEMMs) have been developed with the mutations most commonly seen in the patient population. Expression of these mutations in select cellular compartments has resulted in the ability to recapitulate characteristics of human pancreatic cancer such as the development of …

Bridging The Gap: Assessing Cmv Dnaemia In Kidney Transplant Recipients With Previous Solid Organ Transplants, Goni Katz-Greenberg, Julie M Steinbrink, Krishna Shah, Jennifer S Byrns

Faculty, Staff and Students Publications

Cytomegalovirus (CMV) infection poses a significant threat to solid organ transplant (SOT) recipients and can lead to various complications and adverse outcomes. In an effort to prevent CMV infection, it is common to utilize prophylactic strategies, including antiviral medications such as valganciclovir, especially for high-risk patients. Risk factors for CMV infection in kidney transplant recipients (KTRs) include CMV mismatch between donor and recipient (i.e., donor positive, recipient negative), and intensity of immunosuppression, such as the use of T-cell depleting agents. However, little attention has been given to KTRs with a history of prior SOTs, despite their prolonged exposure to immunosuppressive …

Re: Incidence Of Sars-Cov-2 Breakthrough Infections After Vaccination In Adults: A Population-Based Survey Through 1 March 2023, Stacia M Desantis, Ashraf Yaseen, Tianyao Hao, Luis León-Novelo, Yashar Talebi, Melissa A Valerio-Shewmaker, Cesar L Pinzon Gomez, Sarah E Messiah, Harold W Kohl, Steven H Kelder, Jessica A Ross, Lindsay N Padilla, Mark Silberman, Samantha Wylie, David Lakey, Jennifer A Shuford, Stephen J Pont, Eric Boerwinkle, Michael D Swartz

Faculty, Staff and Student Publications

No abstract provided.

Sars-Cov-2 Serostatus And Covid-19 Illness Characteristics By Variant Time Period In Non-Hospitalized Children And Adolescents, Sarah E Messiah, Michael D Swartz, Rhiana A Abbas, Yashar Talebi, Harold W Kohl, Melissa Valerio-Shewmaker, Stacia M Desantis, Ashraf Yaseen, Steven H Kelder, Jessica A Ross, Lindsay N Padilla, Michael O Gonzalez, Leqing Wu, David Lakey, Jennifer A Shuford, Stephen J Pont, Eric Boerwinkle

Faculty, Staff and Student Publications

OBJECTIVE: to describe COVID-19 illness characteristics, risk factors, and SARS-CoV-2 serostatus by variant time period in a large community-based pediatric sample.

DESIGN: Data were collected prospectively over four timepoints between October 2020 and November 2022 from a population-based cohort ages 5 to 19 years old.

SETTING: State of Texas, USA.

PARTICIPANTS: Participants ages 5 to 19 years were recruited from large pediatric healthcare systems, Federally Qualified Healthcare Centers, urban and rural clinical practices, health insurance providers, and a social media campaign.

EXPOSURE: SARS-CoV-2 infection.

MAIN OUTCOME(S) AND MEASURE(S): SARS-CoV-2 antibody status was assessed by the Roche Elecsys

RESULTS: Over half …

Serinc5 Restricts Hiv Membrane Fusion By Altering Lipid Order And Heterogeneity In The Viral Membrane, Amanda E Ward, Daria Sokovikova, Melvin Neal Waxham, Frederick A Heberle, Ilya Levental, Kandice R Levental, Volker Kiessling, Judith M White, Lukas K Tamm

Faculty, Staff and Student Publications

The host restriction factor, Serinc5, incorporates into budding HIV particles and inhibits their infection by an incompletely understood mechanism. We have previously reported that Serinc5 but not its paralogue, Serinc2, blocks HIV cell entry by membrane fusion, specifically by inhibiting fusion pore formation and dilation. A body of work suggests that Serinc5 may alter the conformation and clustering of the HIV fusion protein, Env. To contribute an additional perspective to the developing model of Serinc5 restriction, we assessed Serinc2 and Serinc5's effects on HIV pseudoviral membranes. By measuring pseudoviral membrane thickness via cryo-electron microscopy and order via the fluorescent dye, …

Antibody Duration After Infection From Sars-Cov-2 In The Texas Coronavirus Antibody Response Survey, Michael D Swartz, Stacia M Desantis, Ashraf Yaseen, Frances A Brito, Melissa A Valerio-Shewmaker, Sarah E Messiah, Luis G Leon-Novelo, Harold W Kohl, Cesar L Pinzon-Gomez, Tianyao Hao, Shiming Zhang, Yashar Talebi, Joy Yoo, Jessica R Ross, Michael O Gonzalez, Leqing Wu, Steven H Kelder, Mark Silberman, Samantha Tuzo, Stephen J Pont, Jennifer A Shuford, David Lakey, Eric Boerwinkle

Faculty, Staff and Student Publications

Understanding the duration of antibodies to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus that causes COVID-19 is important to controlling the current pandemic. Participants from the Texas Coronavirus Antibody Response Survey (Texas CARES) with at least 1 nucleocapsid protein antibody test were selected for a longitudinal analysis of antibody duration. A linear mixed model was fit to data from participants (n = 4553) with 1 to 3 antibody tests over 11 months (1 October 2020 to 16 September 2021), and models fit showed that expected antibody response after COVID-19 infection robustly increases for 100 days postinfection, and predicts …

Innate Lymphoid Cell Characterization And Ilc2s In Neuroinflammation In Aging And Sex Differences, Alexis Mobley, Alexis S. Mobley

Dissertations and Theses (Open Access)

Aging affects immunologic responses by a global immune system suppression, including dysregulation of cytokine mediators, leading to increased inflammation throughout all systems, termed inflammaging. However, understanding healthy aging mechanisms can bypass this effect. Inflammaging also leads to poor outcomes during brain injury, making immune-targeting therapeutics tantamount to overall brain health and longevity. Moreover, sex affects disease etiology and severity through hormonal and chromosomal sex, as the X chromosome contains most immunology-based genes. Androgens have a generally suppressive effect on the immune system. Additionally, when immune responses are mounted, males are better at CD4+ T cell type (Th1) responses, while females …

Methodology To Estimate Natural- And Vaccine-Induced Antibodies To Sars-Cov-2 In A Large Geographic Region, Stacia M Desantis, Luis G León-Novelo, Michael D Swartz, Ashraf S Yaseen, Melissa A Valerio-Shewmaker, Yashar Talebi, Frances A Brito, Jessica A Ross, Harold W Kohl, Sarah E Messiah, Steve H Kelder, Leqing Wu, Shiming Zhang, Kimberly A Aguillard, Michael O Gonzalez, Onyinye S Omega-Njemnob, David Lakey, Jennifer A Shuford, Stephen Pont, Eric Boerwinkle

Faculty, Staff and Student Publications

Accurate estimates of natural and/or vaccine-induced antibodies to SARS-CoV-2 are difficult to obtain. Although model-based estimates of seroprevalence have been proposed, they require inputting unknown parameters including viral reproduction number, longevity of immune response, and other dynamic factors. In contrast to a model-based approach, the current study presents a data-driven detailed statistical procedure for estimating total seroprevalence (defined as antibodies from natural infection or from full vaccination) in a region using prospectively collected serological data and state-level vaccination data. Specifically, we conducted a longitudinal statewide serological survey with 88,605 participants 5 years or older with 3 prospective blood draws beginning …

Conserved Non-Pocket Interactions Drive The Diversity Of Peptide Presentation By Mhc Class I Molecules, Kyle Jackson

Dissertations and Theses (Open Access)

Cytotoxic T-lymphocytes (CTL) can lyse infected or transformed cells through recognition of peptides presented on human leukocyte antigen (HLA) molecules. A thorough understanding of peptide-HLA interactions is needed for improvement of CTL-based immunotherapies. We observed that aspartic acid (D) and glutamic acid (E) at peptide position 4 are highly prevalent in HLA-I peptide ligands, and discovered that they interact with arginine (R) in position 65 and lysine (L) in position 66 of the α1 helix of the binding groove in HLA-A*0201 and HLA-A*2402. Since this interaction differed from well-characterized peptide-HLA anchor interactions mediated by peptide position 2 and the C-terminus, …

The Role Of Pag1 In The Activated B-Cell Subtype Of Diffuse Large B-Cell Lymphoma, Jared Henderson

Dissertations and Theses (Open Access)

Diffuse Large B Cell Lymphoma (DLBCL) is the most common aggressive hematologic malignancy in adults, but despite recent advances in treatment, many patients today still face poor outcomes. Of the two types of DLBCL, activated B-cell (ABC) and germinal center B-cell (GCB), patients diagnosed with the ABC subtype especially face a lack of effective treatment options. Unlike GCB-DLBCL, ABC-DLBCL is characterized by chronic antigen-driven signaling by the B-cell receptor (BCR), indicating an escape from immunologic tolerance mechanisms that normally regulate self-reactive B cells. While recent therapies have focused on inhibiting the kinases that propagate BCR signaling with mixed success, we …

Rejuvenation Of The Epigenetic Landscape Of The Aged Brain Through Manipulation Of Circulating Factors, Edward Koellhoffer

Dissertations and Theses (Open Access)

The aging population of the United States is expanding at an alarming rate. The Center for Disease Control and Prevention estimates that the population of those age 65 years and older will reach over 50 million by 2020 and will double to 100 million by 2060. This will not only put a massive strain on national healthcare resources, but will also increase the number of those who are not able to live and function independently. It is becoming increasingly vital to understand how the brain changes with age and mechanisms to possibly protect and rejuvenate the aged brain to a …

A License To Kill: Understanding Natural Killer Cell Licensing To Fight Cancer, Jolie Schafer

Dissertations and Theses (Open Access)

Natural killer (NK) cell education is an essential developmental process for NK cell effector function, that renders some NK cells “licensed” and others “unlicensed” (with heightened or lowered effector function potential, respectively) against tumor and targets lacking self-molecules. However, the underlying mechanisms responsible for the heightened effector responses of licensed cells remain unknown. Using NK cells derived from humans and expanded ex vivo we performed high-throughput protein expression analysis, and identified multiple proteins that are differentially regulated in licensed and unlicensed human NK cells before and after inhibition by killer-cell immunoglobulin-like receptors (KIRs) and activation by the NKp46 natural cytotoxicity …

Plasmacytoid Dendritic Cell-Mediated Humoral Autoimmunity, Stephanie M. Dorta-Estremera Ph.D.

Dissertations and Theses (Open Access)

Humoral autoimmunity is characterized by the breakdown of B cell immune tolerance to self-antigens and consequent production of pathogenic autoantibodies. Plasmacytoid dendritic cells (pDCs), a potent type I interferon (IFN-I) producer, have been linked to the pathogenesis of systemic lupus erythematosus (SLE), a prototypic systemic humoral autoimmune disease. However, the cellular events that stimulate the development of humoral autoimmunity as a result of pDC activation have not been characterized. Moreover, the B cell subset(s) responsible for the generation of autoantibodies remains to be clearly identified.

The immunization of DNA-containing amyloids into non-autoimmune mice triggers the activation of pDCs and induction …

Defining The Molecular Networks Necessary For Thymus Fate And Organogenesis, Kaitlin A. Reeh

Dissertations and Theses (Open Access)

The thymus and parathyroid (PT) glands originate from endodermal progenitors in the bilateral third pharyngeal pouches (3^rd pps). By E11.5 during mouse development, cells committed to the thymus lineage express Foxn1 whereas PT-fated cells express Gcm2. While these transcription factors are required for organ-specific differentiation, the exact molecular mechanisms that specify endodermal progenitors to either the thymus or parathyroid lineage are not well defined. Tbx1 is initially expressed throughout the 3^rd pp endoderm, as it is required for segmentation of the pharyngeal apparatus, but is downregulated in the thymus-fated domain by E10.5. Despite the widely held notion …

Tethered Il-15 To Augment The Therapeutic Potential Of T Cells Expressing Chimeric Antigen Receptor: Maintaining Memory Potential, Persistence, And Antitumor Activity, Lenka Hurton

Dissertations and Theses (Open Access)

Tethered IL-15 to augment the therapeutic potential of T cells expressing chimeric antigen receptor: Maintaining memory potential, persistence, and antitumor activity

Adoptive immunotherapy can retarget T cells to CD19, a tumor-associated antigen (TAA) expressed on B-cell malignancies, by the expression of a chimeric antigen receptor (CAR). Infusion of CAR-modified T cells for the treatment B-cell malignancies has demonstrated promise in preclinical and clinical trials. These data highlight the ability of infused CD19-specific T cells to be synchronously activated by large burdens of CD19⁺ leukemia and lymphoma. This can lead to dramatic antitumor effects, but also exposes the recipient to …

Immunological Mechanisms Of Extracorporeal Photopheresis In Cutaneous T Cell Lymphoma And Graft Versus Host Disease, Lisa Shiue

Dissertations and Theses (Open Access)

IMMUNOLOGICAL MECHANISMS OF EXTRACORPOREAL PHOTOPHERESIS IN CUTANEOUS T CELL LYMPHOMA AND GRAFT VERSUS HOST DISEASE

Publication No.___________

Lisa Harn-Ging Shiue, B.S.

Supervisory Professor: Madeleine Duvic, M.D.

Extracorporeal photopheresis (ECP) is an effective, low-risk immunomodulating therapy for leukemic cutaneous T cell lymphoma (L-CTCL) and graft versus host disease (GVHD), but whether the mechanism(s) of action in these two diseases is (are) identical or different is unclear. To determine the effects of ECP in vivo, we studied regulatory T cells (T-regs), cytotoxic T lymphocytes (CTLs), and dendritic cells (DCs) by immunofluorescence flow cytometry in 18 L-CTCL and 11 GVHD patients before …

Regulation Of To Xin Synthesis By Clostridium Difficile, Charles Darkoh

Dissertations and Theses (Open Access)

Clostridium difficile is the leading definable cause of nosocomial diarrhea worldwide due to its virulence, multi-drug resistance, spore-forming ability, and environmental persistence. The incidence of C. difficile infection (CDI) has been increasing exponentially in the last decade. Virulent strains of C. difficile produce either toxin A and/or toxin B, which are essential for the pathogenesis of this bacterium. Current methods for diagnosing CDI are mostly qualitative tests that detect the bacterium, the toxins, or the toxin genes. These methods do not differentiate virulent C. difficile strains that produce active toxins from non-virulent strains that do not produce toxins or produce …

Upregulation Of Reactive Oxygen Species During The Retrovirus Life Cycle And Their Roles In A Mutant Of Moloney Murine Leukemia Virus, Ts1-Mediated Neurodegeneration, Soo Jin Kim

Dissertations and Theses (Open Access)

Viral invasion of the central nervous system (CNS) and development of neurological symptoms is a characteristic of many retroviruses. The mechanism by which retrovirus infection causes neurological dysfunction has yet to be fully elucidated. Given the complexity of the retrovirus-mediated neuropathogenesis, studies using small animal models are extremely valuable. Our laboratory has used a mutant moloney murine leukemia retrovirus, ts1-mediated neurodegneration. We hypothesize that astrocytes play an important role in ts1-induced neurodegeneration since they are retroviral reservoirs and supporting cells for neurons. It has been shown that ts1 is able to infect astrocytes in vivo and in …

Plasmacytoid Dendritic Cells Sense Skin Injury And Promote Wound Healing Through Type I Interferons, Josh D. Gregorio

Dissertations and Theses (Open Access)

Plasmacytoid dendritic cells (pDCs) are a rare population of circulating cells, which selectively express intracellular Toll-like receptors (TLR)-7 and TLR-9 and have the capacity to produce large amounts of type I IFNs (IFN-a/b) in response to viruses or host derived nucleic acid containing complexes. pDCs are normally absent in skin but accumulate in the skin of psoriasis patients where their chronic activation to produce IFN-a/b drives the disease formation. Whether pDCs and their activation to produce IFN-a/b play a functional role in healthy skin is unknown. Here we show that pDCs are rapidly and transiently recruited into healthy human and …