scholarly journals P02.11 TREM1 agonist PY159 promotes myeloid cell reprogramming and unleashes anti-tumor immunity

2021 ◽  
Vol 9 (Suppl 1) ◽  
pp. A12.2-A13
Author(s):  
V Juric ◽  
E Mayes ◽  
M Binnewies ◽  
P Canaday ◽  
T Lee ◽  
...  
Keyword(s):  
Tumor Immunity ◽  
Single Agent ◽  
Myeloid Cells ◽  
Human Tumors ◽  
Mouse Tumor ◽  
Neutrophil Chemotaxis ◽  
Syngeneic Mouse ◽  
Cytokines And Chemokines ◽  
Part Time

BackgroundTumor-associated myeloid cells can impede productive anti-tumor immunity. One strategy for targeting immunosuppression is myeloid reprogramming, which drives immunosuppressive myeloid cells to acquire an immunostimulatory phenotype. Triggering receptor expressed on myeloid cells-1 (TREM1) is an immunoglobulin superfamily cell surface receptor expressed on neutrophils and subsets of monocytes and tissue macrophages. TREM1 associates with DAP12 adaptor and induces proinflammatory signaling, amplifies innate immune responses, and is implicated in the development of acute and chronic inflammatory diseases. TREM1 is also enriched in tumors, specifically on tumor-associated myeloid cells. To investigate the potential of TREM1 modulation as an anti-cancer therapeutic strategy, we developed PY159, an afucosylated humanized anti-TREM1 monoclonal antibody, and characterized it in the pre-clinical assays described below.Materials and MethodsAn FcγR binding ELISA and a Jurkat TREM1/DAP12 NFAT-luciferase reporter cell line were used to assess PY159 binding to human FcγRs and TREM1 signaling, respectively. PY159 responses in human whole blood in vitro were evaluated by flow cytometry, transcriptional analysis of sorted leukocyte subsets, and measurement of secreted cytokines/chemokines by MSD. A Transwell system was used to evaluate PY159 effects on neutrophil chemotaxis. TREM1 expression in human tumors was validated by scRNAseq, immunohistochemistry, and flow cytometry. Anti-tumor efficacy of a surrogate anti-mouse TREM1 antibody, PY159m, was evaluated using syngeneic mouse tumor models, either as a single agent or in combination with anti-PD-1.ResultsPY159 afucosylation increased its binding affinity for FcγR and its ability to activate TREM1/DAP12 signaling. In human blood assays, PY159 treatment did not induce depletion of TREM1-expressing cells. Rather, it upregulated monocyte activation markers, promoted neutrophil chemotaxis, and induced proinflammatory cytokines and chemokines, which was dependent on PY159 afucosylation. In human tumors, TREM1 was detected on tumor-associated neutrophils, tumor-associated macrophages, and monocytic myeloid-derived suppressive cells. PY159 induced proinflammatory cytokines and chemokines in dissociated human tumors in vitro, demonstrating that PY159 can reprogram tumor-associated myeloid cells. A surrogate anti-mouse TREM1 antibody, PY159m, exhibited anti-tumor efficacy in several syngeneic mouse tumor models, both as single-agent and in combination with anti-PD-1.ConclusionsThese results show that PY159 is a TREM1 agonist that reprograms myeloid cells and unleashes anti-tumor immunity. PY159 safety and efficacy are currently being evaluated in first-in-human clinical trial (NCT04682431) involving patients resistant and refractory to standard of care therapies.Disclosure InformationV. Juric: A. Employment (full or part-time); Significant; Pionyr Immunotherapeutics Inc. E. Mayes: A. Employment (full or part-time); Significant; Pionyr Immunotherapeutics Inc. M. Binnewies: A. Employment (full or part-time); Significant; Pionyr Immunotherapeutics Inc. P. Canaday: A. Employment (full or part-time); Significant; Pionyr Immunotherapeutics Inc. T. Lee: A. Employment (full or part-time); Significant; Pionyr Immunotherapeutics Inc. S. Dash: A. Employment (full or part-time); Significant; Pionyr Immunotherapeutics Inc. J.L. Pollack: A. Employment (full or part-time); Significant; Pionyr Immunotherapeutics Inc. J. Rudolph: A. Employment (full or part-time); Significant; Pionyr Immunotherapeutics Inc. V. Huang: A. Employment (full or part-time); Significant; Pionyr Immunotherapeutics Inc. X. Du: A. Employment (full or part-time); Significant; Pionyr Immunotherapeutics Inc. N. Jahchan: A. Employment (full or part-time); Significant; Pionyr Immunotherapeutics Inc. A.J. Ramoth: A. Employment (full or part-time); Significant; Pionyr Immunotherapeutics Inc. S. Mankikar: A. Employment (full or part-time); Significant; Pionyr Immunotherapeutics Inc. M. Norng: A. Employment (full or part-time); Significant; Pionyr Immunotherapeutics Inc. C. Santamaria: A. Employment (full or part-time); Significant; Pionyr Immunotherapeutics Inc. K.P. Baker: A. Employment (full or part-time); Significant; Pionyr Immunotherapeutics Inc. L. Liang: A. Employment (full or part-time); Significant; Pionyr Immunotherapeutics Inc.

scholarly journals 859 Tuning the tumor microenvironment by reprogramming TREM1+ myeloid cells to unleash anti-tumor immunity in solid tumors

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A900-A900
Author(s):  
Nadine Jahchan ◽  
Hanna Ramoth ◽  
Vladi Juric ◽  
Erin Mayes ◽  
Shilpa Mankikar ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Tumor Microenvironment ◽  
Tumor Immunity ◽  
Single Agent ◽  
Myeloid Cells ◽  
Mouse Tumor ◽  
Syngeneic Mouse ◽  
Tumor Tissues ◽  
Mouse Tumor Models

BackgroundThe tumor microenvironment (TME) often contains high levels of suppressive myeloid cells that contribute to innate checkpoint inhibitor (CPI) resistance. Pionyr’s Myeloid Tuning approach involves altering the composition and/or the function of myeloid cells in the TME. Myeloid reprogramming alters the function of immunosuppressive myeloid cells to acquire an immunostimulatory phenotype. Triggering receptor expressed on myeloid cells-1 (TREM1) is an immunoglobulin superfamily cell surface receptor enriched on tumor-associated myeloid cells. To investigate the potential of TREM1 modulation as an anti-cancer therapeutic strategy, Pionyr developed an afucosylated humanized anti-TREM1 monoclonal antibody termed PY159 and characterized it in pre-clinical and translational biomarker assays described below.MethodsPY159 responses in human whole blood and dissociated primary tumor cells in vitro were evaluated by flow cytometry and measurement of secreted cytokines and chemokines by MSD. TREM1 expression in human tumors was validated by scRNAseq, flow cytometry, and immunohistochemistry (IHC). In vivo efficacy and pharmacodynamic studies of a surrogate anti-mouse TREM1 antibody, termed PY159m, were evaluated using syngeneic mouse tumor models, either as a single-agent or in combination with anti-PD-1. To select tumor types and patients most likely to benefit from PY159 therapy, Pionyr developed qualitative and quantitative monoplex and multiplex IHC assays that detect TREM1 expression levels in human tumor tissues.ResultsPY159 treatment in vitro induced signaling, upregulated monocyte activation markers, and induced proinflammatory cytokines. In human tumors, TREM1 was detected on tumor-associated neutrophils, tumor-associated macrophages, and monocytic myeloid-derived suppressive cells. The surrogate PY159m anti-mouse TREM1 antibody exhibited anti-tumor efficacy in several syngeneic mouse tumor models, both as single-agent and in combination with anti-PD-1. Screening for TREM1 expression in tumor tissues demonstrated that TREM1+ tumor associated myeloid cells were highly enriched in the TME of multiple solid tumor indications. The monoplex and multiplex IHC assays offered insights into the localization of TREM1+ myeloid cells and their spatial relationship with other immune cells present in the TME to determine what immune composition will be more favorable for response to PY159 therapy.ConclusionsCollectively, the available nonclinical data support PY159 as a TREM1 agonist that reprograms myeloid cells and unleashes anti-tumor immunity. PY159 safety and efficacy are currently being evaluated in first-in-human clinical trial (NCT04682431) involving select advanced solid tumors patients resistant and refractory to standard of care therapies alone and in combination with a CPI. The TREM1 IHC assay is successfully being used on FFPE archival tumor tissues from enrolled patients to determine TREM1 expression levels.

705 Anti-tumor activity of CB-668, a potent, selective and orally bioavailable small-molecule inhibitor of the immuno-suppressive enzyme Interleukin 4 (IL-4)-Induced Gene 1 (IL4I1)

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A747-A747
Author(s):  
Andrew MacKinnon ◽  
Deepthi Bhupathi ◽  
Jason Chen ◽  
Tony Huang ◽  
Weiqun Li ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Tumor Microenvironment ◽  
Immune Cell ◽  
Interleukin 4 ◽  
Mouse Tumor ◽  
Syngeneic Mouse ◽  
Molecule Inhibitor ◽  
Anti Tumor Activity ◽  
Mouse Tumor Models

BackgroundTumors evade destruction by the immune system through multiple mechanisms including altering metabolism in the tumor microenvironment. Metabolic control of immune responses occurs through depletion of essential nutrients or accumulation of toxic metabolites that impair immune cell function and promote tumor growth. The secreted enzyme interleukin 4 (IL-4)-induced gene 1 (IL4I1) is an L-phenylalanine oxidase that catabolizes phenylalanine and produces phenyl-pyruvate and hydrogen peroxide. IL4I1 regulates several aspects of adaptive immunity in mice, including inhibition of cytotoxic T cells through its production of hydrogen peroxide (reviewed in1). In human tumors, IL4I1 expression is significantly elevated relative to normal tissues and is notably high in ovarian tumors and B cell lymphomas. Motivated by the hypothesis that IL4I1 is an immuno-metabolic enzyme that suppresses anti-tumor immunity, we discovered CB-668, the first known small-molecule inhibitor of IL4I1.MethodsIL4I1 enzymatic activity was measured using an HRP-coupled enzyme assay. RNA in-situ hybridization was carried out on the RNAScope platform. Syngeneic mouse tumor models were used to evaluate the anti-tumor activity of CB-668. The level of phenyl-pyruvate in tumor homogenates was measured by LC/MS.ResultsOur clinical candidate, CB-668 is a potent and selective non-competitive inhibitor of IL4I1 (IC50 = 15 nM). CB-668 has favorable in vitro ADME properties and showed low clearance and high oral bioavailability in rodents. Twice-daily oral administration of CB-668 was well-tolerated in mice and resulted in single-agent anti-tumor activity in the syngeneic mouse tumor models B16-F10, A20, and EG7. Oral CB-668 administration reduced the levels of phenyl-pyruvate in the tumor, consistent with inhibition of IL4I1 enzymatic activity. Anti-tumor activity of CB-668 was immune cell-mediated since efficacy was abrogated in CD8-depleted mice, and CB-668 treatment caused increased expression of pro-inflammatory immune genes in the tumor. Moreover, CB-668 had no direct anti-proliferative activity on tumor cells grown in vitro (IC50 > 50 µM). CB-668 also favorably combined with anti-PD-L1 therapy to reduce tumor growth in the B16-F10 tumor model.ConclusionsThese data support an immune-mediated anti-tumor effect of IL4I1 inhibition by CB-668, and suggest inhibition of IL4I1 represents a novel strategy for cancer immuno-therapy.ReferencesMolinier-Frenkel V, Prévost-Blondel A, and Castellano F. The IL4I1 Enzyme: A New Player in the Immunosuppressive Tumor Microenvironment. Cells 2019;8:1–9.

scholarly journals 323 Immunogenic syngeneic model MC38-OVA for the preclinical evaluation of immune evasion and checkpoint blockade

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A348-A348
Author(s):  
Jessie Wang ◽  
Kaixia Lian ◽  
Jia Zheng ◽  
Chenpan Nie ◽  
Annie An ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Tumor Immunity ◽  
Immune Evasion ◽  
Syngeneic Mouse ◽  
Ifn Γ ◽  
Draining Lymph Nodes ◽  
Syngeneic Tumors

BackgroundThe development of immuno-oncology (I/O) therapeutics has revolutionized the cancer treatment landscape. Despite this achievement, the mechanism behind limited responses is poorly understood. Tumor immune evasion has been reported to arise through the loss of tumor necrosis factor (TNF) signaling, interferon-γ (IFN-γ) signaling, and antigen presentation pathways, which are crucial to CD8+ T cell-mediated killing. Syngeneic mouse models have been widely used as they have an intact immune system, are easily accessible, and have a vast array of historical data for comparison. However, limited syngeneic models respond to immune checkpoint inhibitors, possibly due to low intrinsic immunogenicity. The expression of ovalbumin (OVA) has previously shown to sufficiently alter the susceptibility of syngeneic tumors to host T cell-mediated responses. In this study, the newly developed OVA-expressing MC38 syngeneic line was characterized for tumor immunity, checkpoint blockade response and response durability.MethodsMurine colon cancer MC38 cells were transduced by lentiviral vector with chicken OVA coding cDNA. A single clone was selected, and OVA expression was confirmed by western blot. The MC38-OVA cells were subcutaneously implanted into immunocompetent mice to evaluate the tumorigenicity and in vivo response to anti-PD-1 antibody treatment. Blood was collected 2 days post final dose of anti-PD-1 treatment for phenotypic analysis by FACS. Spleen and tumor draining lymph nodes were collected at termination for FACS analysis of IFN-γ+ T cells and OVA specific CD8+ T cells. Adoptive transfer was evaluated by challenge studies in both MC38-OVA and MC38 tumor-bearing mice with T cells derived from MC38-OVA mice, anti-PD-1 cured mice and OT-I mice. In vitro killing assays were performed to evaluate the function of adoptive CD3+ T cells transfer.ResultsOVA-expressing MC38 presented complete regression under anti-PD-1 treatment in vivo. T cell expansion was observed after anti-PD-1 treatment in peripheral blood with increased IFN-γ+ T cells in both tumor-draining lymph nodes and spleen. Additionally, anti-PD-1 cured mice generated robust tumor specific memory T cell, which successfully inhibited MC38-OVA and MC38 tumor growth following adoptive transfer. CD3+ T cells from MC38-OVA-bearing mice and OT-I mice showed anti-tumor immunity in vivo. In vitro killing assay demonstrated increased immunity.ConclusionsSyngeneic mouse tumor models are preferred preclinical models for I/O research, despite limited intrinsic immunogenicity. OVA expression in syngeneic tumors largely increased T cell-mediated immunity to enhance antigen-specific T cell responses during tumorigenesis, providing novel immunogenic models for preclinical immunotherapy evaluation.

scholarly journals P04.05 Modulating tumor microenvironment with arginase-1 specific T cells

2020 ◽  
Vol 8 (Suppl 2) ◽  
pp. A38.2-A39
Author(s):  
E Martinenaite ◽  
M Aaboe Joergensen ◽  
RE Johansson Mortensen ◽  
S Munir Ahmad ◽  
SE Weis-Banke ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Tumor Microenvironment ◽  
Therapeutic Effect ◽  
Potential Role ◽  
Myeloid Cells ◽  
Tumor Site ◽  
Arginase 1 ◽  
Part Time

BackgroundCancer progression is associated with an increased immune suppression at the tumor site. Arginase-1 is an enzyme well-known for its involvement in metabolic immune regulation. At the tumor site, arginase-1 acts by reducing availability of L-arginine to the infiltrating immune cells thus reducing T cell functionality and proliferation. While arginase-1 is expressed by some tumor cells, it has also been shown to be produced by immune inhibitory myeloid cells, such as myeloid derived suppressor cells (MDSCs), tumor associated macrophages (TAMs) and is associated with poor prognosis. Previously, we demonstrated that spontaneous CD4+ and CD8+ T-cell immune responses against arginase-derived, HLA-restricted peptides can be found in both cancer patients and healthy individuals (Martinenaite et al, 2018, DOI: 10.1080/2162402X.2017.1404215). These T cells are present in the memory T cell compartment, and that they are activated in arginase-1 inducing conditions, such as presence of TH2 cytokines IL-4 or IL-13 in vitro (Martinenaite et al, 2019, DOI: 10.1038/s41423-019-0231-3 and DOI: 10.1007/s00262-019-02425-6).Methods and ResultsIn order to explore if arginase-1-specific T cells have a potential role in modulation of immune homeostasis, human arginase-1-specific memory T cells were isolated and expanded for functional characterization. We show that arginase-1-specific T cells specifically recognize arginase-1 expressing cells, such as mRNA transfected autologous dendritic cells (DCs) and B cells as well as M2 polarized macrophages in vitro. In addition, activated arginase-1-specific T cells produce pro-inflammatory cytokines IFNγ and TNFα. Secretion of TH1 cytokines by these T cells suggests potential role as potent immune modulators in the tumor microenvironment, since many arginase-1 expressing myeloid cells are not terminally differentiated and they can be re-polarized to an immunostimulatory, M1-like phenotype. We also observed that targeting of M2-polarized arginase-1 expressing monocytic leukemia cell line THP-1 with arginase-1-specific CD4+ T cells induces upregulation of PD-L1 on the THP-1 cells. Furthermore, we demonstrate that an arginase-1-derive peptide vaccine has a therapeutic effect in syngeneic mouse tumor models (B16 and MC38), both as monotherapy and in combination with anti-PD-1 treatment. The therapeutic effect was associated with increased immune infiltration in the peptide vaccinated mice compared to the control.ConclusionsOur study provides evidence that immune modulatory vaccination targeting arginase-1 is an intriguing way of targeting the immune suppressive microenvironment.Disclosure InformationE. Martinenaite: A. Employment (full or part-time); Significant; IO Biotech. M. Aaboe Joergensen: None. R.E. Johansson Mortensen: None. S. Munir Ahmad: None. S.E. Weis-Banke: None. M. Orebo Holmström: None. A. Wakatsuki Pedersen: A. Employment (full or part-time); Significant; IO Biotech. Ö. Met: None. I.M. Svane: F. Consultant/Advisory Board; Significant; IO Biotech. M. Hald Andersen: A. Employment (full or part-time); Significant; IO Biotech.

scholarly journals Interleukin-15 after Near-Infrared Photoimmunotherapy (NIR-PIT) Enhances T Cell Response against Syngeneic Mouse Tumors

Cancers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2575 ◽  
Author(s):  
Yasuhiro Maruoka ◽  
Aki Furusawa ◽  
Ryuhei Okada ◽  
Fuyuki Inagaki ◽  
Hiroaki Wakiyama ◽  
...  
Keyword(s):  
T Cells ◽  
Tumor Growth ◽  
Cancer Cell ◽  
Near Infrared ◽  
Single Agent ◽  
T Cell Response ◽  
Host Immunity ◽  
Mouse Tumor ◽  
Syngeneic Mouse ◽  
Interleukin 15

Near infrared photoimmunotherapy (NIR-PIT) is a newly developed and highly selective cancer treatment that employs a monoclonal antibody (mAb) conjugated to a photo-absorber dye, IRDye700DX, which is activated by 690 nm light. Cancer cell-targeted NIR-PIT induces rapid necrotic/immunogenic cell death (ICD) that induces antitumor host immunity including re-priming and proliferation of T cells. Interleukin-15 (IL-15) is a cytokine that activates natural killer (NK)-, B- and T-cells while having minimal effect on regulatory T cells (Tregs) that lack the IL-15 receptor. Here, we hypothesized that IL-15 administration with cancer cell-targeted NIR-PIT could further inhibit tumor growth by increasing antitumor host immunity. Three syngeneic mouse tumor models, MC38-luc, LL/2, and MOC1, underwent combined CD44-targeted NIR-PIT and short-term IL-15 administration with appropriate controls. Comparing with the single-agent therapy, the combination therapy of IL-15 after NIR-PIT inhibited tumor growth, prolonged survival, and increased tumor infiltrating CD8+ T cells more efficiently in tumor-bearing mice. IL-15 appears to enhance the therapeutic effect of cancer-targeted NIR-PIT.

scholarly journals 884 Engineered toxin body mediated depletion of TIGIT expressing immune cells for cancer immunotherapy

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A926-A926
Author(s):  
Elizabeth Saputra ◽  
Garrett Cornelison ◽  
Jennifer Mitchell ◽  
Karia Williams ◽  
Andrea Mendiola ◽  
...  
Keyword(s):  
T Cells ◽  
Immune Cells ◽  
Immune Cell ◽  
Single Agent ◽  
Antibody Fragment ◽  
Cell Surface Receptor ◽  
Mouse Tumor ◽  
List Type ◽  
Proof Of Concept

BackgroundTIGIT (T cell immunoreceptor with Ig and ITIM domains) is an exciting novel target for immuno-oncology which functions as an immune checkpoint on multiple immune cell types including memory CD8+, CD4+ Treg, and memory CD4+ cells. TIGIT upregulation on tumor infiltrating lymphocytes (TILs) has been observed in multiple cancer types and contributes to an immunosuppressive tumor microenvironment (TME). Interestingly, TIGIT is commonly co-expressed with PD-1 on Tregs in the TME, tumor antigen specific CD8+ T cells and CD8+ TILs, leading to weakened anti-tumor immune responses.1–2 To date, TIGIT inhibiting monoclonal antibodies (mAb) have shown little activity as a monotherapy in clinical and preclinical studies. 3–4 Therefore, current clinical trials are now focused on combining TIGIT mAbs with known commercial PD-1 or PD-L1 mAbs. A TIGIT-specific engineered toxin body (ETB) represents a wholly new approach to targeting TIGIT expressing cells including those co-expressing TIGIT and PD-1.MethodsETBs targeting TIGIT were designed to deplete TIGIT-expressing TILs, including Tregs, directly in the TME. ETBs are proteins that consist of an antibody fragment genetically fused to a proprietary de-immunized (DI) form of the Shiga-like toxin A subunit (SLTA). These proteins are specific for a cell surface receptor, and function through triggering rapid internalization upon binding, followed by an enzymatic and irreversible termination of ribosomal protein synthesis resulting in cellular apoptosis. Here we provide proof of concept for ETBs as a novel modality for the depletion of TIGIT-expressing immune cells.ResultsTIGIT-targeting ETBs exhibit potent in vitro cytotoxicity of TIGIT over-expressing cell lines (IC50<1nM). These ETBs also lead to apoptotic depletion of ex vivo TIGIT-expressing regulatory T cells (Tregs) from healthy donors. In mixed culture assays, TIGIT ETBs increase the proliferation of TIGIT negative T cells by depleting TIGIT-expressing T cells.ConclusionsStudies to assess pharmacodynamics and efficacy of TIGIT targeting ETBs using a double knock-in (TIGIT and PD-1) mouse tumor model are ongoing, but these early proof of concept in vitro data support the hypothesis that ETBs can deplete TIGIT positive immune cell populations including those co-expressing PD-1. It is possible that targeted TIGIT inhibition through ETB-induced cell death could tip the balance towards tumor regression by eliminating this novel checkpoint (and TIGIT/PD-1 co-expression) at the level of the TME.ReferencesJinhua X, Ji W, Shouliang C, Liangfeng Z. Expression of immune checkpoints in T cells of esophageal cancer patients. Oncotarget 2016;7(39):1–10.Blessin NC, Simon R, Kluth M, Fischer K, et al. Patterns of TIGIT expression in lymphatic tissue, inflammation and cancer. Dis Markers 2019;2019:1–13.Johnston RJ, Comps-Agrar L, Hackney J, Yu X, et al. The immunoreceptor TIGIT regulates anti-tumor and antiviral CD8(+) T effector function. Cancer Cell 2014;26(6):923–927.Bendell JC, Bedrad P, Bang Y-J, LoRusso P, et al. Phase Ia/Ib dose-escalation study of the anti-TIGIT antibody Tiragolumab as a single agent and in combination with atezolizumab in patients with advanced solid tumors. Proceedings: AACR Annual Meeting 2020; April 27–28, 2020 and June 22–24, 2020; Philadelphia, PA.

scholarly journals TIGIT and PD-1 Immune Checkpoint Pathways Are Associated With Patient Outcome and Anti-Tumor Immunity in Glioblastoma

2021 ◽  
Vol 12 ◽  
Author(s):  
Itay Raphael ◽  
Rajeev Kumar ◽  
Lauren H. McCarl ◽  
Karsen Shoger ◽  
Lin Wang ◽  
...  
Keyword(s):  
T Cell ◽  
Tumor Immunity ◽  
Immune Checkpoint ◽  
Single Agent ◽  
Myeloid Cells ◽  
Suppressor Cells ◽  
Tumor Infiltrating Lymphocytes ◽  
The Cancer Genome Atlas ◽  
High Rate ◽  
Pd1 Blockade

Glioblastoma (GBM) remains an aggressive brain tumor with a high rate of mortality. Immune checkpoint (IC) molecules are expressed on tumor infiltrating lymphocytes (TILs) and promote T cell exhaustion upon binding to IC ligands expressed by the tumor cells. Interfering with IC pathways with immunotherapy has promoted reactivation of anti-tumor immunity and led to success in several malignancies. However, IC inhibitors have achieved limited success in GBM patients, suggesting that other checkpoint molecules may be involved with suppressing TIL responses. Numerous IC pathways have been described, with current testing of inhibitors underway in multiple clinical trials. Identification of the most promising checkpoint pathways may be useful to guide the future trials for GBM. Here, we analyzed the The Cancer Genome Atlas (TCGA) transcriptomic database and identified PD1 and TIGIT as top putative targets for GBM immunotherapy. Additionally, dual blockade of PD1 and TIGIT improved survival and augmented CD8+ TIL accumulation and functions in a murine GBM model compared with either single agent alone. Furthermore, we demonstrated that this combination immunotherapy affected granulocytic/polymorphonuclear (PMN) myeloid derived suppressor cells (MDSCs) but not monocytic (Mo) MDSCs in in our murine gliomas. Importantly, we showed that suppressive myeloid cells express PD1, PD-L1, and TIGIT-ligands in human GBM tissue, and demonstrated that antigen specific T cell proliferation that is inhibited by immunosuppressive myeloid cells can be restored by TIGIT/PD1 blockade. Our data provide new insights into mechanisms of GBM αPD1/αTIGIT immunotherapy.

Use of PD-L1 and ICOSL to discriminate innate and adaptive dendritic cells in the head and neck cancer microenvironment.

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. e14184-e14184
Author(s):  
Caroline Hoffmann ◽  
Aurore Surun ◽  
Floriane Noel ◽  
Paula Michea ◽  
Maximilien Grandclaudon ◽  
...  
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
T Cell ◽  
Head And Neck ◽  
Cd4 T Cells ◽  
Myeloid Cells ◽  
Treatment Modalities ◽  
Highly Efficient ◽  
Cytokines And Chemokines

e14184 Background: Inflamed head and neck squamous cell carcinomas (HNSCC), have a better prognosis independently of the treatment modalities, and have an increased response rate to PD(L)1 blockade. Dendritic cells (DC) infiltration is associated to T cell infiltration and DC are critical in the immune response to cancer, but little is known on HNSCC infiltrating DC. The objectives were to determine the differences between DC infiltrating inflamed vs non inflamed tumors, to understand which mechanisms modulate DC phenotypes and which are the associated functions. Methods: 22 untreated HNSCC were characterized by flow cytometry for their immune infiltrate. RNA sequencing of sorted tumor infiltrating myeloid subsets and blood DC were analyzed for differentially expressed genes. The TMod database (Grandclaudon et al.), testing the effect of various stimuli on DC and subsequently on co-cultured T cells, was used to decipher DC and T cell modulation. Results: The level of CD3 infiltration was positively associated to the level of DC infiltration and PDL1 expression on myeloid cells, and negatively to the level neutrophils and of ICOSL expression on myeloid cells. PDL1high ICOSLneg DC from inflamed tumors were matched with the “innate DC” phenotype described in vitro, highly efficient at secreting cytokines and chemokines but poorly activating naïve CD4 T cells. DC from non-inflamed tumor resembled immature medium DC. A third type of DC, “adaptive DC”, expressing high levels of ICOSL and low of PDL1, poorly efficient at cytokine and chemokine secretion, but highly efficient at activating T cells is was described in vitro, but not found in tumors. RNAseq analysis confirmed this innate polarization and highlighted that those cells present a mature and NFkB activated phenotype. Conclusions: Inflamed HNSCC contain stimuli able to induce the recruitment and the differentiation of DC into mature, NFkB activated “innate” DC, highly efficient at secreting cytokines and chemokines but poorly activating naïve CD4 T cells. These data partly explain the superiority of CPS over TPS for the prediction of response to PD(L)1 blockade. More importantly, the stimuli identified here may be used as adjuvants to induce this DC « innate » maturation in non-inflamed tumors, but should only be used in combination with anti-PD(L)1 immunotherapy.

SBT6050, a HER2-directed TLR8 therapeutic, as a systemically administered, tumor-targeted human myeloid cell agonist.

2020 ◽  
Vol 38 (15_suppl) ◽  
pp. 3110-3110
Author(s):  
Heather Metz ◽  
Monica Childs ◽  
Jamie Brevik ◽  
Damion Winship ◽  
Ty Brender ◽  
...  
Keyword(s):  
Tumor Cells ◽  
Cytokine Production ◽  
Single Agent ◽  
Myeloid Cells ◽  
Myeloid Cell ◽  
Clinical Development ◽  
Innate Immune ◽  
Mouse Tumor ◽  
Systemic Delivery ◽  
Mouse Tumor Models

3110 Background: Solid tumors are replete with myeloid cells which, when activated, drive potent anti-tumor responses. Clinical development of systemically administered myeloid cell agonists, however, has been hindered by acute toxicities due to peripheral activation of the targeted cell types. Intratumoral administration, the route of delivery typically used for innate immune/myeloid cell agonists, is limited by tumor accessibility and a dependence on abscopal responses. A systemically delivered myeloid cell agonist with tumor-localized activity has the potential to overcome challenges encountered with other innate immune/myeloid cell agonists in clinical development. Methods: SBT6050 is a novel therapeutic comprised of a potent toll-like receptor (TLR) 8 agonist payload conjugated to a HER2-directed monoclonal antibody. Delivery of the payload into the endosome of human myeloid cells, where TLR8 resides, requires the co-engagement of HER2 on tumor cells and Fc gamma receptor on human myeloid cells. Thus, SBT6050 is designed for systemic delivery and tumor-targeted activation of human myeloid cells. Results: Studies with human immune cells show that SBT6050 potently induces, in a HER2-dependent manner, multiple anti-tumor immune activities due to its direct activation of myeloid cells and the subsequent induction of T and NK cell cytolytic activity. SBT6050 is designed to activate human myeloid cells only in the presence of HER2-positive tumor cells with moderate (2+ by IHC) or high (3+ by IHC) expression levels. Tumor-localized activity has been demonstrated in mouse models using a SBT6050 mouse surrogate. Systemic delivery results in robust single agent efficacy in multiple mouse tumor models, even those engineered to lack T cells, without accompanying peripheral cytokine production. Trastuzumab and SBT6050 bind to distinct epitopes on HER2 and enhanced activity is observed when the two agents are combined. Conclusions: SBT6050 is a systemically administered, tumor-targeted myeloid cell agonist that demonstrates single agent efficacy in multiple mouse tumor models without peripheral cytokine production. A first-in-human study with SBT6050 is expected to begin this year for patients with HER2-expressing solid tumors.

scholarly journals TISMO: syngeneic mouse tumor database to model tumor immunity and immunotherapy response

2021 ◽  
Author(s):  
Zexian Zeng ◽  
Cheryl J Wong ◽  
Lin Yang ◽  
Nofal Ouardaoui ◽  
Dian Li ◽  
...  
Keyword(s):  
Tumor Immunity ◽  
Expression Profiles ◽  
Data Reuse ◽  
Specific Gene ◽  
Mouse Tumor ◽  
Rna Seq ◽  
Web Interfaces ◽  
Syngeneic Mouse ◽  
Syngeneic Mouse Model ◽  
Cancer Types

Abstract Syngeneic mouse models are tumors derived from murine cancer cells engrafted on genetically identical mouse strains. They are widely used tools for studying tumor immunity and immunotherapy response in the context of a fully functional murine immune system. Large volumes of syngeneic mouse tumor expression profiles under different immunotherapy treatments have been generated, although a lack of systematic collection and analysis makes data reuse challenging. We present Tumor Immune Syngeneic MOuse (TISMO), a database with an extensive collection of syngeneic mouse model profiles with interactive visualization features. TISMO contains 605 in vitro RNA-seq samples from 49 syngeneic cancer cell lines across 23 cancer types, of which 195 underwent cytokine treatment. TISMO also includes 1518 in vivo RNA-seq samples from 68 syngeneic mouse tumor models across 19 cancer types, of which 832 were from immune checkpoint blockade (ICB) studies. We manually annotated the sample metadata, such as cell line, mouse strain, transplantation site, treatment, and response status, and uniformly processed and quality-controlled the RNA-seq data. Besides data download, TISMO provides interactive web interfaces to investigate whether specific gene expression, pathway enrichment, or immune infiltration level is associated with differential immunotherapy response. TISMO is available at http://tismo.cistrome.org.

Sign in / Sign up

Export Citation Format

Share Document