RNASeq of plasmacytoid dendritic cells in head and neck squamous cell cancer patients
ABSTRACT: Plasmacytoid dendritic cells (pDC) are a subset of dendritic cells with unique immunophenotypic properties and functions. While their role in antiviral immunity through production of type I interferons is well-established, their contributions to anti-tumor immunity are less clear. While some evidence demonstrates that pDC in the tumor microenvironment (TME) may drive CD4+ T cell to become Foxp3+ T regulatory cells, little is understood about the relationship of pDC with cytotoxic CD8+ T cell, the key player in antitumor immune responses. In this study, we perform comprehensive immunophenotyping and functional analysis of pDC from the TME and draining lymph nodes of patients with head and neck squamous cell carcinoma (HNSCC) and identify a novel pDC subset characterized by expression of the TNF receptor superfamily member CD134 (OX40). We show that OX40 expression is expressed on intratumoral pDC in both humans and mice in a tumor-model specific fashion... (for more see dbGaP study page.)
Project description:Epigenetic regulators have emerged as exciting targets for cancer therapy. Additionally, restoration of antitumor immunity by blocking the PD-L1 signaling using antibodies has proven to be beneficial in cancer therapy. Here we show that BET bromodomain inhibition suppresses PD-L1 expression and restores antitumor immunity in ovarian cancer. CD274 (encoding PD-L1) is a direct target of BRD4-mediated gene transcription. In mouse models, treatment with the BET inhibitor JQ1 significantly reduced PD-L1 expression on tumor cells and tumor-associated dendritic cells and macrophages, which correlated with an increase in the activity of antitumor cytotoxic T cells. Together, these data demonstrate an epigenetic approach to block PD-L1 signaling to restore antitumor immunity. Given the fact that BET inhibitors have been proven safe with manageable reversible toxicity in clinical trials, our findings indicate that pharmacological BET inhibitors represent a novel treatment strategy for targeting PD-L1 expression. Overall design: RNA-seq for JQ1 treated and shBRD4 knockdown cells with controls
Project description:This is a mathematical model of a growing tumor and its interaction with the immune system. The model consists of four populations: tumor cells, dendritic cells (representing the innate immune system), cytotoxic T cells, and helper T cells (as the specific immune system). The model is comprised of a system of ordinary differential equations.
Project description:Gene expression of Treg cells that have lost Foxp3 expression and acquired Il4 expression following adoptive transfer into T-cell deficient mice (HpTR-IL-4gfp+), cmpared to conventional Treg cells isolated from H. polygyrus-infected wild-type mice (HpTR) and Th2 cells generated from naïve T cells following adoptive transfer into H. polygyrus-infected T-cell deficient mice (nT-IL-4gfp+). Immunity to intestinal helminth infections requires the rapid activation of T helper 2 (Th2) cells. However, simultaneous expansion of regulatory CD4+Foxp3+ T (Treg) cells impedes protective responses, resulting in chronic infections. The ratio between regulatory and effector T cells can therefore determine the outcome of infection. The re-differentiation of Treg into T helper (Th) cells has been identified in hyper-inflammatory diseases. In this study, we asked whether ex-Treg Th2 cells develop and contribute to type 2 immunity. Using multi-gene reporter and fate-reporter systems we demonstrate that a significant proportion of Th2 cells derive from Foxp3+ cells following Heligmosomoides polygyrus infection and airway allergy. Ex-Foxp3 Th2 cells exhibit characteristic Th2 effector functions and provide immunity to H. polygyrus. Through selective deletion of Il4ra on Foxp3+ cells, we further demonstrate IL-4 is required for the development of ex-Foxp3 Th2 cells. Collectively, our findings indicate that converting Treg cells into Th2 cells could concomitantly enhance Th2 cells and limit Treg-mediated suppression. Overall design: Naïve T cells were FACS-sorted from naive wild-type mice. HpTR cells were FACS-sorted from H. polygyrus-infected mice. HpTR cells and nT cells were transferred to T-cell deficient mice infected with H. polygyrus. IL-4gfp-expressing cells were FACS-sorted from HpTR (HpTR-IL-4gfp+) or nT (nT-IL-4gfp+) recipients. 3 biological samples were obtained from 3 independent experiments for each sample group.
Project description:Through a diversity of functional lineages, cells of the innate and adaptive immune system either drive or constrain immune reactions within tumors. Thus, while the immune system has a powerful ability to recognize and kill cancer cells, this function is often suppressed preventing clearance of disease. The transcription factor (TF) BACH2 controls the differentiation and function of multiple innate and adaptive immune lineages, but its role in regulating tumor immunity is not known. Here, we demonstrate that BACH2 is required to establish immunosuppression within tumors. We found that growth of subcutaneously implanted tumors was markedly impaired in Bach2-deficient mice and coincided with intratumoral activation of both innate and adaptive immunity but was dependent upon adaptive immunity. Analysis of tumor-infiltrating lymphocytes in Bach2-deficient mice revealed high frequencies of CD4+ and CD8+ effector cells expressing the inflammatory cytokine IFN-γ. Lymphocyte activation coincided with reduction in the frequency of intratumoral CD4+ Foxp3+ regulatory T (Treg) cells. Mechanistically, Treg-dependent inhibition of CD8+ T cells was required for BACH2-mediated tumor immunosuppression. These findings demonstrate that BACH2 is a key component of the molecular programme of tumor immunosuppression and identify a new target for development of therapies aimed at reversing immunosuppression in cancer. Analysis of tumor-infiltrating lymphocytes in Bach2-deficient mice revealed high frequencies of CD4+ and CD8+ effector cells expressing the inflammatory cytokine IFN-γ. Lymphocyte activation coincided with reduction in the frequency of intratumoral CD4+ Foxp3+ regulatory T (Treg) cells. Mechanistically, Treg-dependent inhibition of CD8+ T cells was required for BACH2-mediated tumor immunosuppression.
Project description:Alterations in myelopoiesis are common across various tumor types, resulting in immature populations termed myeloid-derived suppressor cells (MDSCs). MDSC burden correlates with poorer clinical outcomes, credited to their ability to suppress antitumor immunity. MDSCs consist of two major subsets, monocytic and polymorphonuclear (PMN). Intriguingly, the latter subset predominates in many patients and tumor models, though the mechanisms favoring PMN-MDSC responses remain poorly understood. Ordinarily, lineage-restricted transcription factors regulate myelopoiesis that collectively dictate cell fate. One integral player is interferon regulatory factor-8 (IRF8), which promotes monocyte/dendritic cell differentiation while limiting granulocyte development. We recently showed that IRF8 inversely controls MDSC burden in tumor models, particularly the PMN-MDSC subset. However, where IRF8 acts in the pathway of myeloid differentiation to influence PMN-MDSC production has remained unknown. Here, we showed that: 1) tumor growth was strongly associated with a selective expansion of newly defined IRF8lo granulocytic progenitors (GPs); 2) tumor-derived GPs had an increased ability to form PMN-MDSCs; 3) tumor-derived GPs shared gene expression patterns with IRF8-/- GPs, suggesting that IRF8 loss underlies GP expansion; and 4) enforced IRF8 overexpression in vivo selectively constrained tumor-induced GP expansion. These findings support the hypothesis that PMN-MDSCs result from selective expansion of IRF8lo GPs, and that strategies targeting IRF8 expression may limit their load to improve immunotherapy efficacy. Overall design: 3 groups of mice: 1) non-tumor-bearing (NTB) control; 2) mice orthotopically implanted with 4T1 mammary tumor cells (4T1-TB); mice genetically deficient in IRF8 expression and function (KO-GP)
Project description:Tumors cause the induction or repression of many genes associated with inflammation. To investigate the up and down regulation of genes associated with immune stimulation or immune tolerance RNA was isolated from dendritic cells from normal or tumor bearing prostate for microarray analysis. Using the TRansgenic Adenocarcinoma of the Mouse Prostate (TRAMP) model and a fold change comparison system we identified genes that are associated with immune tolerance to be up-regulated and genes associated with immunity to be down regulated in tumor associated dendritic cells. Keywords: Comparative gene expression, prostate cancer, dendritic cells Prostatic dendritic cells were isolated from 4 normal and 6 tumor bearing mice for comparison of gene expression.
Project description:Tumors cause the induction or repression of many genes associated with inflammation. To investigate the up and down regulation of genes associated with immune stimulation or immune tolerance RNA was isolated from dendritic cells from normal or tumor bearing prostate for microarray analysis. Using the TRansgenic Adenocarcinoma of the Mouse Prostate (TRAMP) model and a fold change comparison system we identified genes that are associated with immune tolerance to be up-regulated and genes associated with immunity to be down regulated in tumor associated dendritic cells. Keywords: Comparative gene expression, prostate cancer, dendritic cells Overall design: Prostatic dendritic cells were isolated from 4 normal and 6 tumor bearing mice for comparison of gene expression.
Project description:Vα24 invariant natural killer T (iNKT) cells are a subset of T lymphocytes implicated in the regulation of broad immune responses. They recognize lipid antigens presented by CD1d on antigen-presenting cells and induce both innate and adaptive immune responses, which enhance effective immunity against cancer, represent promising therapeutic target. However, reduced iNKT-cell numbers and function have been observed in many patients with cancer. To overcome this obstacle, we reprogramed human iNKT cells to pluripotency and then redifferentiated into regenerated iNKT cells in vitro through IL-7/IL-15-based optimized cytokine combination. They showed proliferation and IFN-γ production in response to α-galactosylceramide, induced dendritic cell maturation and downstream activation of cancer antigen-specific cytotoxic T lymphocytes in vitro, and exhibited NKG2D- and DNAM-1-mediated natural killer celllike cytotoxicity against cancer cell lines. Their immunological features and availability in an unlimited supply from induced pluripotent stem cells offer the potential to develop effective immunotherapies against cancer. Overall design: Expression profile of the lymphocytes (n = 17) by highthrouput sequencing
Project description:We identified germline heterozygous mutations in CTLA4 in members of four families with severe immune dysregulation. Human CTLA4 haploinsufficiency caused dysregulation of FoxP3+ regulatory T (Treg) cells and lymphocytic infiltration of target organs, mimicking Ctla4 homozygous mice. Patients also exhibited a B cell phenotype, with progressive loss of B cells and accumulation of autoreactive CD21lo B cells. This study demonstrates a critical quantitative role for CTLA-4 in human immune homeostasis.
Project description:Regulatory T cells (Tregs) are critical for maintaining self-tolerance and immune homeostasis, but their suppressive function can impede effective anti-tumor immune responses. Foxp3 is a transcription factor expressed in Tregs that is required for their function. The pathways and microenvironmental cues governing Foxp3 expression and Treg function are not completely understood. We found that Yes-associated protein (YAP), a co-activator of the Hippo pathway, is highly expressed in Tregs and bolsters Foxp3 expression and Treg function in vitro and in vivo. To assess how YAP influences patterns of gene expression in Tregs, naïve CD4+ T cells and Tregs were isolated from wild type mice and CD4+ T cell lineage-restricted YAP knockout mice (YAPflox/flox, CD4-Cre+). Gene expression by naïve CD4+ T cells and their resting and stimulated Treg counterparts was analyzed by RNASeq. Our findings reveal that YAP ablation undermines expression of multiple genes involved in the TGFβ/SMAD signaling pathway in Tregs including Activin. These findings suggest that YAP potentiates activity along a pro-Treg signaling axis. Overall design: The gene expression patterns in naïve T cells and nTregs from Wild type and YAP cKO (YAP flox/flox,CD4-Cre+) mice were assessed and compared using RNASeq. Sequencing was performed using a Illumina Hiseq2000.