Immunotherapy Commons^™

Pi3kδ Inhibition Alters Cd8 T Cell Differentiation And Reprograms The Tumor Microenvironment Following Adoptive Immunotherapy, Alexandrea Joy Turnquist

Dartmouth College Ph.D Dissertations

T cell exhaustion remains a significant barrier to effective adoptive cell therapy in solid tumors. Here, we demonstrate that in vitro treatment with the PI3Kδ inhibitor CAL-101 generates T cells with enhanced stemness and metabolic fitness, though the stemness of these cells is not dependent on HIF-1α -dependent mechanisms. These cells show increased mitochondrial dependence and spare respiratory capacity while maintaining normal basal metabolism. Under chronic antigen stimulation, CAL-101-treated T cells, including human T cells, resist terminal exhaustion and maintain stem-like properties. Using single-cell RNA sequencing and spatial transcriptomics of B16 melanoma tumors, we found that CAL-101-treated T cells preferentially …

Bridging Bench To Bedside: Developing Sup2-Il-33 Armored Car T Cells For Translational Immunotherapy, Shannon Lynn Ferry

Dartmouth College Ph.D Dissertations

Despite some promising results, CAR T cell therapy elicits limited responses in most patients with solid tumors. Armoring CAR T cells with immunomodulatory cytokines improves efficacy in solid tumors. We previously reported that administering IL-2 superkine (Sup2) and IL-33 cytokine armored CAR T cells without host pre-conditioning is sufficient to broadly activate host immunity to delay growth of B16F10 melanoma in immunocompetent B6 mice. However, lymphodepleting pre-conditioning prior to CAR T cell infusion is routinely utilized to enable engraftment of adoptively transferred cells. Here we assess the efficacy TRP1-specific CAR T cells with or without Sup2 and IL-33 armoring following …

Macrophage Heterogeneity And Function In The Lung, Xin Li

Dartmouth College Ph.D Dissertations

Macrophages are critical custodians of the lung, orchestrating immune surveillance, maintaining tissue homeostasis, and coordinating both innate and adaptive responses. This dissertation examines their heterogeneity and specialized functions, focusing on IMs, which reside in the lung interstitium, and AMs, which occupy the airspace. Through comprehensive single-cell transcriptomic profiling of murine and human samples, we identify multiple IM and AM subsets defined by distinct chemokine, cytokine, receptor, and innate immune gene signatures. These subsets display clear divisions of labor, contributing to immune cell recruitment, tertiary lymphoid structure formation, and alveolar homeostasis.

In IMs, coordinated chemokine programs not only recruit inflammatory cells …

Regulation And Therapeutic Targeting Of Virus-Specific Resident Memory T Cells, Jordan Fredriksen Isaacs

Dartmouth College Ph.D Dissertations

CD8+ T cells are critical to the immune response to pathogens, as they kill infected cells and generate immunologic memory. Following infection, antigen-specific T cells expand approximately 10,000-fold and migrate to sites of inflammation in order to clear the pathogen. Once infection is resolved, a small pool of memory T cells persist in circulation and within tissues ready to respond rapidly upon re-exposure. Given the importance of CD8+ T cells, significant efforts have been made over the years to better understand how different memory T cell subsets are established, maintained, and regulated. The most recently identified subset, resident memory T …

Investigating The Mechanisms For Priming And Maintaining Tumor Ag Specific Cd8+ T Cell Responses In The Context Of Cd4-Depletion, Delaney E. Ramirez

Dartmouth College Ph.D Dissertations

Achieving durable, systemic CD8+ T cell responses against tumors is an imperative goal in treating cancer. However, suppressive cells, including Foxp3+CD4+ regulatory T cells (Tregs) are widely recognized to inhibit CD8+ T cell activity. For nearly two decades, anti-CD4 treatment has been used to eliminate Tregs and induces durable tumor antigen (Ag) specific CD8+ T cells, despite also depleting Foxp3-negative conventional CD4+ T (Tconv) cells. However, the underlying mechanism of anti-CD4 efficacy is not understood. In Chapter Three, we look beyond Treg depletion and investigate the potential contributions of other factors including homeostatic space, depletion of CD4+ APCs, and presence …

Driving Cars Down Memory Lane: Uncovering Car Memory T Cell And Antigenspecific Endogenous T Cells Importance In Durable Responses Against Melanoma, Asmaa Mohamed

Dartmouth College Ph.D Dissertations

Responsiveness to chimeric antigen receptor (CAR) T cell therapy correlates with CAR T cell expansion and persistence in vivo. Multiple working strategies improve CAR T cell persistence by increasing stem-like properties or by sustaining CAR T cell activity with combination therapies. Herein, we describe the intrinsic ability of CAR T cells to differentiate into memory T cells, the effect of cytokine armoring, and neoadjuvant CD4 depletion therapy on CAR and tumor-specific endogenous memory T cells. TRP1-specific CAR T cells alone or in combination with Super2 + IL-33 (S233) armoring and/or CD4 depletion therapy were evaluated in the immunocompetent B16F10 melanoma …

Molecular Mechanisms Governing The Generation Of Tissue Resident Memory Cd8 T Cells In The Setting Of Cancer, Nikhil Khatwani

Dartmouth College Ph.D Dissertations

Although there has been extensive research on T-cell responses to cancer immunotherapy, the understanding of long-lasting memory in visceral organs remains less well understood. Among these, a population of Trm cells was discovered that reside durably within tumor draining lymph nodes (TDLN) and plays a crucial role in protecting against invading melanoma cells, uncovering a new role for Trm cells at critical metastatic sites. However, little is known about the molecular mechanisms promoting Trm establishment in tissues where cancer can develop and metastasize. Here, employing longitudinal T cell receptor (TCR)-lineage-tracing and single-cell transcriptomics, we find that TDLN contain Teff cells …

Cell-Typing And Interaction Analysis Of The Immune Compartment Of The Tumor Microenvironment Using High-Resolution Omics Modalities, Courtney Taylor Schiebout

Dartmouth College Ph.D Dissertations

Single-cell RNA-sequencing (scRNA-seq) has provided a new frontier for the investigation of complex tissues. One ideal candidate for the utilization of this method is the tumor microenvironment (TME). The TME is often host to a complex set of cell populations and behaviors that can be highly influential for cancer inhibition or progression. This is especially true of the immune compartment of the TME: the presence of certain types of immune cells in the TME and their expression profiles can significantly affect cancer prognosis in some cases. By providing individual cell-level gene expression data, scRNA-seq can be highly informative for characterizing …

Response And Molecular Control Of Cd8 T Cells During Infection And Cancer, Nicholas K. Preiss Dr.

Dartmouth College Ph.D Dissertations

CD8 T cells are potent immune effector cells capable of vast clonal expansion and clearance of infected or cancerous cells. After control of the pathogenic insult, CD8 T cells develop into quiescent, long-lived memory populations that are poised to mediate rapid protection upon reencounter with cognate antigen. These properties make control of CD8 T cell responses a highly desirable outcome of vaccine strategies and immunotherapy. Therefore, understanding how the effector function and memory differentiation of CD8 T cells are controlled at a molecular level is of great importance. In the context of infection with gammaherpesviruses (γHV), which form a latent …

In Situ Vaccination Using Plant Viral Particles As A Novel Approach For Cancer Immunotherapy, Chenkai Mao

Dartmouth College Ph.D Dissertations

Non-infectious to mammals, genetically, and physically stable plant virus-based nanoparticles have been increasingly studied as a novel platform for cancer vaccine and adjuvants due to their immunogenic properties. Our prior work showed that, empty cowpea mosaic virus (eCPMV), a plant virus-like particle (VLP) that is composed of a separated capsid, is an excellent in situ vaccine (ISV) for cancer immunotherapy; however, little is known about the mechanisms linked to their activities regarding recognition and antigen presentation.

In the present studies, we report cowpea mosaic virus (CPMV) and RNA-lacking CPMV (empty, eCPMV) are both toll like receptor (TLR) agonists for TLRs …

Profiling Durable Anti-Tumor Memory T Cell Responses In Long-Term Melanoma Survivors, Jichang Han

Dartmouth College Ph.D Dissertations

While T-cell responses to cancer immunotherapy have been avidly studied,

long-lived memory has been poorly characterized. Of melanoma patients who

receive immunotherapy, long-term survivors are frequently found to develop

melanoma-associated vitiligo. Our prior work showed in a preclinical model that

vitiligo skin sustained a long-lived CD8+ resident memory T cell (TRM) population,

playing key roles in perpetuating anti-tumor immunity. However, the characteristics

and longevity of these memory T cells in melanoma survivors have not been defined.

In the present studies, we probed both the CD8+ and CD4+ T cell responses,

focusing on memory T cell responses in a cohort of …