Medicine and Health Sciences Commons^™

Defining The Cooperation Between Mhc-I And Mhc-Ii Neoantigen-Driven T Cell Responses To Develop Effective Personalized Immunotherapies, Charmelle Williams

Dissertations & Theses (Open Access)

Immune checkpoint therapy (ICT) (e.g. anti-CTLA-4 (α-CTLA-4), anti-PD-1 (α-PD-1)) enables durable T cell-dependent anti-tumor immunity in certain cancer patients. Since a subset of patients respond to ICT, this work aims at developing a more in-depth understanding of T-cell responses to MHC class I (MHC-I) and MHC class II (MHC-II) tumor antigens that are derived from aberrant expression of non-mutant antigens or driver and passenger somatic alterations that can function as tumor neoantigens. We used a poorly immunogenic Braf^v600e Pten^-/- Cdkn2a^-/- YUMM1.7 (Y1.7) murine melanoma line with a paucity of endogenous neoantigens that is unresponsive to ICT, and …

The Role Of The Hypoxia-Inducible Factor 2 In Pancreatic Cancer: Mechanisms Of Tumor Immunosuppression And Intestinal Radioprotection, Carolina Garcia Garcia

Dissertations & Theses (Open Access)

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with dismal prognosis. The only curative option for patients is surgery, but over 80% of patients are not surgical candidates. Unfortunately, PDAC is resistant to the three remaining options. PDAC is characterized by a profoundly hypoxic and immunosuppressive stroma, which contributes to its therapeutic recalcitrance. Alpha-smooth muscle actin+ (αSMA+) cancer-associated fibroblasts (CAFs) are the most abundant stromal component, as well as mediators of stromal deposition. The hypoxia-inducible factors (HIF1 and HIF2) coordinate responses to hypoxia, yet, despite their known association to poor patient outcomes, their functions within the PDAC tumor microenvironment (TME) …

Investigation Of The Functional Impact Of Anti-Pd-1 On Tumor-Infiltrating Lymphocytes (Til) And Mapping Of Tumor Genomic Features Relevant For Response To Til Therapy, Caitlin Creasy

Dissertations & Theses (Open Access)

With the growing use of both cellular and antibody-based immunotherapies, it has become more important to uncover biomarkers to predict patient response to therapy and ideally aid in patient selection for specific therapeutics, thereby enhancing treatment outcome. At MD Anderson, we have a 43% response rate to therapy when treating metastatic melanoma patients with adoptive cell therapy (ACT) of tumor-infiltrating lymphocytes (TIL), but it is unknown what makes the other 57% of patients not respond to therapy. It is further unknown how particularly early doses of checkpoint inhibitors, like anti-PD-1, attribute to TIL functionality, adding another confounding factor in determining …

Memory Potential, Molecular Characterization, And Translational Applications Of The Novel Theo/Tceo T Cell Phenotype, Todd Bartkowiak, Todd Bartkowiak

Dissertations & Theses (Open Access)

T cells comprise a substantial arm of the immune system and are exquisitely adapted to combat pathogens and tumors. The inflammatory environment largely dictates the nature of T cell response. A hallmark of T cell-mediated immunity is formation of immunological memory; the ability to respond more potently to re-encounter with pathogens. The immune system is also capable of recognizing tumors as foreign, much like viral or bacterial pathogens. Tumors have evolved, though, to generate an immunosuppressive environment to avoid destruction. The field of immunotherapy seeks to overcome immune suppression, in part by targeting T cell co-receptors on the cell surface …

Dynamic Assessment Of Nk Cell Interactions With Pediatric Tumor Cells To Predict Response To Immunotherapy, Arianexys Aquino Lopez

Dissertations & Theses (Open Access)

Due to Natural Killer (NK) cells’ capacity to target tumor cells without prior sensitization, adoptive NK cell therapy represents a promising immunotherapy approach for pediatric cancer patients. Our laboratory has developed an NK cell expansion protocol that generates large quantities of NK cells for therapeutic infusion. Given that NK cells are heterogeneous, with variable receptor expression and potential to target tumor cells, the purpose of my study was to determine whether subpopulations of NK cells with enhanced anti-tumor potential could be identified for increased potency of the NK cell infusion product. In addition, we previously showed that our expanded NK …

Integrative Cancer Immunogenomic Analysis Of Serial Melanoma Biopsies Reveals Correlates Of Response And Resistance To Sequential Ctla-4 And Pd-1 Blockade Treatment, Whijae Roh

Dissertations & Theses (Open Access)

Melanoma is the most malignant form of skin cancer. The five-year survival rate for metastatic melanoma is 19.9%. Although targeted therapy of BRAF and MEK inhibitors were developed for melanoma, resistance to therapy is inevitable. Immune checkpoint blockade, which reverses the suppression of the immune system, on the other hand, has shown a durable response in 20-30% of patients with metastatic melanoma. However, more predictive and robust biomarkers of response to this therapy are still needed, and resistance mechanisms remain incompletely understood. To address this, we examined a cohort of metastatic melanoma patients treated with sequential checkpoint blockade against cytotoxic …

Developing Novel Approaches To Improve Response To T Cell Based Cancer Immunotherapy, Rina M. Mbofung

Dissertations & Theses (Open Access)

Recently, T cell based immunotherapies have moved to the forefront of cancer immunotherapy with the success of Adoptive T cell therapy (ACT) and Immune checkpoint blockade.ACT, where patients are treated with tumour infiltrating T cells (TILs), conferred a clinical response rate of ~50%. Treatment with anti-CTLA4 and anti –PD1 therapy, conferred response rates of up to 50%, greatly improving the overall survival of patients with advanced melanoma amongst other cancer types. Despite the encouraging outcomes, there are relatively low response rates coupled with the delay of weeks to months before tumour shrinkage can be appreciated. Thus, understanding what tumour intrinsic …

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 & 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 …

T-Cell Treatments For Solid And Hematological Tumors, Drew C. Deniger

Dissertations & Theses (Open Access)

Cell-based therapies have demonstrated potency and efficacy as cancer treatment modalities. T cells can be dichotomized by their T cell receptor (TCR) complexes where alpha/beta T cells (95% of T cells) and gamma/delta T cells (+T cells proliferated to clinically significant numbers and ROR1⁺ tumor cells were effectively targeted and killed by both ROR1-specific CAR⁺ T cell populations, although ROR1RCD137 were superior to ROR1RCD28 in clearance of leukemia xenografts in vivo. The second specific aim focused on generating bi-specific CD19-specific CAR⁺ gamma/delta T cells with polyclonal TCRgamma/delta repertoire on CD19⁺ artificial antigen presenting cells (aAPC). …