scholarly journals 768 Systemic delivery of a tumor-targeted TLR9 agonist conjugate transforms the tumor immune landscape and induces tumor regression in mice

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A803-A803
Author(s):  
Caitlyn Miller Candidate ◽  
Idit Sagiv-Barfi ◽  
Patrick Neuhoefer ◽  
Debra Czerwinski ◽  
Steven Artandi ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cells ◽  
T Cell ◽  
B Cells ◽  
Tumor Targeting ◽  
Tumor Regression ◽  
Breast Tumors ◽  
Live Cells ◽  
Systemic Delivery ◽  
Tlr9 Agonist

BackgroundTumor-localized delivery of Toll-like receptor (TLR) agonists is a promising strategy to promote immune activation within the tumor microenvironment (TME) to overcome tumor immunosuppression and induce anti-tumor immune responses. To enable localization to multiple tumor sites following systemic administration, we developed a fully-synthetic tumor-targeting TLR9 agonist and demonstrate its potential to transform the tumor immune microenvironment for effective tumor regression in mice.MethodsAn engineered synthetic peptide (PIP) that binds to multiple integrin receptors overexpressed in many solid tumors was chemically conjugated to a synthetic CpG oligonucleotide (TLR9 agonist), thereby generating a tumor-targeting immune-stimulant referred to as PIP-CpG. To facilitate clinical translation, PIP-CpG is cross-reactive between mouse, non-human primate, and human. Therapeutic studies were conducted in immune-competent mice bearing breast or pancreatic tumors to evaluate the efficacy of intravenously (IV)-injected PIP-CpG compared to IV-injected unmodified CpG or vehicle (PBS). We then performed mechanistic studies to evaluate the immune response elicited by PIP-CpG therapy.ResultsIntravenous dosing of PIP-CpG led to tumor regression and prolonged survival, and in some cases cures, relative to vehicle or unmodified CpG therapy in both murine breast (4T1) and pancreatic cancer (KPC-G2) models. This tumor regression was dependent on T cells as T cell depletion resulted in loss of therapeutic response. To study the effect of systemic therapy on the cellular landscape in the TME, we analyzed 4T1 breast tumors by flow cytometry. We found that vehicle and CpG IV-dosed mice had immunosuppressive TMEs comprised mostly of myeloid-derived suppressor cells (MDSCs; 43–68% of live cells) with minimal infiltrating T cells and B cells (5–16% of live cells). In contrast, the TME of PIP-CpG treated mice was transformed into a lymphocyte-rich “hot” tumor phenotype with massive infiltration by T cells and B cells (92–95% of live cells) and plummeting levels of MDSCs (down to ~1%). In addition, tumor-specific effector CD8+ T cells were generated in response to PIP-CpG therapy, but not CpG dosed IV, indicating that PIP-CpG therapy transforms the TME and elicits a T cell-mediated tumor-specific immune response. Furthermore, PIP-CpG was effective for treating MMTV-PyMT transgenic mice, which spontaneously develop multiple breast tumors. Murine toxicity studies indicated that effects of PIP-CpG were similar to CpG dosed IV or intratumorally, which have been well-tolerated in human clinical trials.ConclusionsTumor-directed systemic delivery of a TLR9 agonist transforms the TME via activated B and T cells and is promising for further development in patients with solid tumors.Ethics ApprovalAll mouse experiments were performed in accordance with protocols approved by the Stanford Administrative Panel on Laboratory Animal Care.

scholarly journals Anti–4-1bb Monoclonal Antibodies Abrogate T Cell–Dependent Humoral Immune Responses in Vivo through the Induction of Helper T Cell Anergy

1999 ◽  
Vol 190 (10) ◽  
pp. 1535-1540 ◽  
Author(s):  
Robert S. Mittler ◽  
Tina S. Bailey ◽  
Kerry Klussman ◽  
Mark D. Trailsmith ◽  
Michael K. Hoffmann
Keyword(s):  
Immune Response ◽  
T Cells ◽  
Monoclonal Antibodies ◽  
T Cell ◽  
B Cells ◽  
Humoral Immunity ◽  
Cd8 T Cells ◽  
Immunodeficient Mice ◽  
Humoral Immune

The 4-1BB receptor (CDw137), a member of the tumor necrosis factor receptor superfamily, has been shown to costimulate the activation of T cells. Here we show that anti–mouse 4-1BB monoclonal antibodies (mAbs) inhibit thymus-dependent antibody production by B cells. Injection of anti–4-1BB mAbs into mice being immunized with cellular or soluble protein antigens induced long-term anergy of antigen-specific T cells. The immune response to the type II T cell–independent antigen trinintrophenol-conjugated Ficoll, however, was not suppressed. Inhibition of humoral immunity occurred only when anti–4-1BB mAb was given within 1 wk after immunization. Anti–4-1BB inhibition was observed in mice lacking functional CD8+ T cells, indicating that CD8+ T cells were not required for the induction of anergy. Analysis of the requirements for the anti–4-1BB–mediated inhibition of humoral immunity revealed that suppression could not be adoptively transferred with T cells from anti–4-1BB–treated mice. Transfer of BALB/c splenic T cells from sheep red blood cell (SRBC)-immunized and anti–4-1BB–treated mice together with normal BALB/c B cells into C.B-17 severe combined immunodeficient mice failed to generate an anti-SRBC response. However, B cells from the SRBC-immunized, anti–4-1BB–treated BALB/c mice, together with normal naive T cells, exhibited a normal humoral immune response against SRBC after transfer, demonstrating that SRBC-specific B cells were left unaffected by anti–4-1BB mAbs.

scholarly journals Interleukin 1-induced, T cell-mediated regression of immunogenic murine tumors. Requirement for an adequate level of already acquired host concomitant immunity.

1988 ◽  
Vol 168 (6) ◽  
pp. 2031-2043 ◽  
Author(s):  
R J North ◽  
R H Neubauer ◽  
J J Huang ◽  
R C Newton ◽  
S E Loveless
Keyword(s):  
Immune Response ◽  
T Cells ◽  
T Cell ◽  
Tumor Growth ◽  
Tumor Regression ◽  
Interleukin 1 ◽  
Host Immunity ◽  
Antitumor Action ◽  
Complete Regression ◽  
Subtherapeutic Level

Intraperitoneal injection of human rIL-1 in a dose of 0.5 microgram daily for 5 d, or 1 microgram daily for 3 d, was capable of causing complete regression of immunogenic SA1 sarcoma growing subcutaneously in syngeneic or semisyngeneic mice. Higher doses of IL-1 were not more therapeutic against the SA1 sarcoma, but needed to be given to cause complete regression of the immunogenic L5178Y lymphoma. On the other hand, the P815 mastocytoma was much less responsive to IL-1 therapy, in that it failed to undergo complete regression in response to doses of IL-1 capable of causing regression of the L5178Y lymphoma. IL-1 caused regression of the SA1 sarcoma when given on days 6-8 of tumor growth, but not when given on days 1-3. This refractoriness of a small tumor to IL-1 therapy suggests that the antitumor action of IL-1 is based on an underlying host-immune response that is not generated until after day 3 of tumor growth. Direct evidence for the participation of host immunity in IL-1-induced tumor regression was supplied by results showing that IL-1 was not therapeutic against the SA1 sarcoma growing in T cell-deficient (TXB) mice, unless these mice were first infused with Ly-2+ and L3T4+ T cells from donor mice bearing an established SA1 sarcoma. In contrast, normal T cells, or T cells from donor mice bearing a YAC-1 lymphoma, failed to provide TXB recipients with the ability to cause regression of their SA-1 sarcoma in response to IL-1 treatment. The results are in keeping with the interpretation that exogenous IL-1, by augmenting the production of tumor-sensitized T cells, converts a subtherapeutic level of host immunity to a therapeutic level. The results suggest, in addition, that IL-1 only stimulates the replication of T cells that are already engaged in the antitumor immune response.

Preoperative treatment to modify the immune microenvironnement of liver colorectal metastases.

2015 ◽  
Vol 33 (3_suppl) ◽  
pp. 602-602 ◽  
Author(s):  
Marc Van Den Eynde ◽  
Bernhard Mlecnik ◽  
Jean-Pascal H. Machiels ◽  
Daphne Debetancourt ◽  
Gabriela Bindea ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cells ◽  
B Cells ◽  
Tumor Regression ◽  
Colorectal Metastases ◽  
Tumor Regression Grade ◽  
Preoperative Treatment ◽  
Prognostic Impact ◽  
Histological Response ◽  
Primary Colorectal Tumor

602 Background: We previously reported that an adaptive Th1 immune response (CD3/CD8/CD45RO T-cells) observed in resected primary colorectal tumor and liver colorectal metastases (LCM) is an important prognostic factor. B and FoxP3 regulatory lymphocytes participate to the modulation of this response. We aimed to investigate whether the preoperative treatments influenced the quality and the density of the immune infiltrates previously reported in the LCM. Methods: We used a cohort of metastatic colorectal patients (n=107) engaged for curative liver surgery with available FFPE blocks for all resected LCM to confirm the prognostic impact of the immune response. Among this cohort of 338 LCMs, 46 were completely resected after chemotherapy (CT) alone, 130 after CT + anti-VEGF, 118 after CT + anti-EGFR and 44 after surgery alone. LCMs were analyzed for histological response according the Tumor Regression Grade (TRG) and regrouped as Response (R, TRG1-3) or No Response (NR, TRG4-5). The density of CD3+ (T-cells), CD8+ (cytotoxic), CD45RO+ (memory), CD20+ (B-cells) and FoxP3+ (regulatory) in the core (CT) and invasive margin (IM) of all LCM was quantified on immunostained slides. The mean density value (CT/IM) was calculated for each marker with a dedicated image analysis software on whole-slide imaging. Comparisons were made using the Wilcoxon-Mann-Whitney test. Results: LCMs showing R (compared to NR and untreated LCM) were more frequently associated with a high immune infiltrate for CD3+ (CT: p<0.005; IM: p<0.05), CD8+ (CT: p<0.005; IM: p<0.005) and CD20+ (CT: p<0.05). Conversely, high FoxP3+ density in the CT and IM was related to NR and untreated LCMs (p<0.01). LCMs treated with an anti-EGFR therapy showed higher densities of CD3+ (CT: p<0.005; IM: p<0.01), CD8+ (CT: p<0.005), CD45RO+ (CT: p<0.005), CD20+ (CT: p<0.005) and FoxP3+ (CT: p<0.05; IM: p<0.005) compared to other treatments and untreated LCMs. Conclusions: Preoperative treatment modifies the LCM immune microenvironnement. LCMs with a histological response show a cytotoxic immune response (CD3+/CD8+) with associated B-cells (CD20+) and downregulated Tregs (FoxP3+). The use of an anti-EGFR therapy significantly increases immune infiltration in the CT.

scholarly journals Notch1-Activated B Cells Have an Immunomodulatory Function Enhancing Th2 and Treg Immune Response Via IL-33-ST2 Pathway

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 130-130
Author(s):  
Hiroshi Arima ◽  
Momoko Nishikori ◽  
Yasuyuki Otsuka ◽  
Kiyotaka Izumi ◽  
Wataru Kishimoto ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cells ◽  
T Cell ◽  
B Cells ◽  
B Cell ◽  
Cell Fate ◽  
Research Funding ◽  
Pharmaceutical Research ◽  
Fate Decision ◽  
Activated B Cells

Abstract Notch1 signaling pathway is involved in T-cell fate decision and development, but it is also known to be activated in B cells upon anti-IgM or LPS stimulation. In addition to its physiological upregulation in B cells, Notch1 signaling is often aberrantly activated in several lymphoid malignancies of B-cell origin, such as classical Hodgkin lymphoma, mantle cell lymphoma and chronic lymphocytic leukemia. However, functional roles of Notch1 in B cells have not been well elucidated to date. Here we report a novel immunomodulatory role of Notch1-activated B cells that alters T-cell immune response in an IL-33-dependent manner. Functional analysis of Notch1 in mature B cells had been hampered by its substitutability for Notch2, which is involved in early B-cell fate decision towards marginal zone B cells (Zhang et. al. J Immunol 2013). To eliminate such irrelevant effect of Notch1 on early B-cell differentiation, we generated a mouse model in which Notch1 intracellular domain (NICD), a constitutively active form of Notch1, began to be expressed in mature B cells after AICDA promoter-dependent Cre expression in germinal centers (StopFloxed-NICD Tg mice×Aicda-Cre mice, hereby designated as NICD Tg mice). In this mouse model, NICD transgene was expressed in about 5% of total splenic B cells, with normal B cell maturation and differentiation. Alternatively, subsets of splenic CD4+ T cells were significantly altered, with increase in Th2 and Treg cells and decrease in Th1 and Th17 cells. IFN-γ production by CD8+ T cells was also significantly reduced. Consequently, NICD Tg mice were susceptible to fungal infections, and more importantly, they began to die of spontaneous malignant neoplasms such as sarcoma and lymphoma at 9 months of age. The tumor development was further increased when TP53 gene was heterozygously deleted in NICD Tg mice. None of the tumors having developed in NICD Tg mice expressed the NICD transgene, suggesting that these tumors did not develop as a result of direct oncogenic effect of NICD. As serum levels of IFN-γ and TNF-α were significantly lower in NICD Tg mice than in control mice, it was rather suggested that these tumors had developed under a condition of suppressed anti-tumor immunity. To elucidate the mechanism of immunomodulatory activity of Notch1-activated B cells, we performed a comparative gene expression analysis using B cells from NICD Tg and control mice. Among several candidate genes whose expression levels were increased in Notch1-activated B cells, we focused on elevated IL-33 as a potential cause for the immunomodulation. Upregulation of IL-33 protein in Notch1-activated B cells was validated by intracellular cytokine flow cytometry. IL-33 is a cytokine that is expressed in nuclei of broad types of cells in their resting state. However, we found that it was also present in the cytoplasm of Notch1-activated B cells, suggesting that IL-33 is actively produced in these cells. To confirm whether extracellular release of IL-33 from B cells was enhanced through Notch1, we cultured splenic B cells from wild-type mice with LPS stimulation in the presence of L cells with or without Notch1 ligand Delta-like 1 (Dll1) expression. We found that IL-33 secretion from B cells was increased twofold in the presence of Dll1-positive compared to Dll1-negative L cells. As expected, the Dll1-mediated increase in IL-33 levels was successfully blocked by DAPT, a Notch signaling inhibitor. To determine whether the IL-33 secreted from Notch1-activated B cells was responsible for the functional modulation of T cells, we cultured wild-type CD4+ T cells with B cells from NICD Tg or control mice, and measured cytokine levels produced by T cells. As a result, IL-4, IL-13 and IL-10 secretion was markedly increased when T cells were cocultured with Notch1-activated B cells. Strikingly, the increase in these Th2- and Treg-associated cytokine levels was completely canceled by addition of a blocking antibody against the IL-33 receptor ST2. In summary, we have shown that Notch1-activated B cells have a novel immunomodulatory function to alter T-cell immunity towards Th2 and Treg immune response via IL-33 secretion, thereby suppressing cellular immunity. This immunomodulatory mechanism may potentially be utilized by Notch1-activated B-cell neoplasms to escape anti-tumor immunity, and we propose that the Notch1-IL-33-ST2 axis can be a promising target for immunotherapy of lymphoid malignancies. Disclosures Nishikori: Kyowa Kirin: Honoraria; Eisai: Honoraria, Research Funding; Janssen Pharmaceutical: Honoraria. Takaori-Kondo:Alexion Pharmaceuticals: Research Funding; Mochida Pharmaceutical: Research Funding; Shionogi: Research Funding; Eisai: Research Funding; Takeda Pharmaceutical: Research Funding; Astellas Pharma: Research Funding; Kyowa Kirin: Research Funding; Chugai Pharmaceutical: Research Funding; Pfizer: Research Funding; Janssen Pharmaceuticals: Speakers Bureau; Merck Sharp and Dohme: Speakers Bureau; Bristol-Myers Squibb: Speakers Bureau; Toyama Chemical: Research Funding; Cognano: Research Funding.

scholarly journals Reduced Expression of Autophagy Markers and Expansion of Myeloid-Derived Suppressor Cells Correlate With Poor T Cell Response in Severe COVID-19 Patients

2021 ◽  
Vol 12 ◽  
Author(s):  
Sergej Tomić ◽  
Jelena Đokić ◽  
Dejan Stevanović ◽  
Nataša Ilić ◽  
Alisa Gruden-Movsesijan ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cells ◽  
T Cell ◽  
B Cells ◽  
Cell Response ◽  
Suppressor Cells ◽  
T Cell Response ◽  
T Cell Subsets ◽  
Myeloid Derived Suppressor Cells ◽  
Immunological Mechanisms

Widespread coronavirus disease (COVID)-19 is causing pneumonia, respiratory and multiorgan failure in susceptible individuals. Dysregulated immune response marks severe COVID-19, but the immunological mechanisms driving COVID-19 pathogenesis are still largely unknown, which is hampering the development of efficient treatments. Here we analyzed ~140 parameters of cellular and humoral immune response in peripheral blood of 41 COVID-19 patients and 16 age/gender-matched healthy donors by flow-cytometry, quantitative PCR, western blot and ELISA, followed by integrated correlation analyses with ~30 common clinical and laboratory parameters. We found that lymphocytopenia in severe COVID-19 patients (n=20) strongly affects T, NK and NKT cells, but not B cells and antibody production. Unlike increased activation of ICOS-1+ CD4+ T cells in mild COVID-19 patients (n=21), T cells in severe patients showed impaired activation, low IFN-γ production and high functional exhaustion, which correlated with significantly down-regulated HLA-DR expression in monocytes, dendritic cells and B cells. The latter phenomenon was followed by lower interferon responsive factor (IRF)-8 and autophagy-related genes expressions, and the expansion of myeloid derived suppressor cells (MDSC). Intriguingly, PD-L1-, ILT-3-, and IDO-1-expressing monocytic MDSC were the dominant producers of IL-6 and IL-10, which correlated with the increased inflammation and accumulation of regulatory B and T cell subsets in severe COVID-19 patients. Overall, down-regulated IRF-8 and autophagy-related genes expression, and the expansion of MDSC subsets could play critical roles in dysregulating T cell response in COVID-19, which could have large implications in diagnostics and design of novel therapeutics for this disease.

A Novel IL-12-TIM-3 Pathway Induces T Cell Exhaustion and Predicts Reduced Survival In Patients with Follicular B-Cell Non-Hodgkin Lymphoma

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 143-143
Author(s):  
Zhi-Zhang Yang ◽  
Deanna Grote ◽  
Steven Ziesmer ◽  
Toshiro Niki ◽  
Mitsuomi Hirashima ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cells ◽  
T Cell ◽  
B Cells ◽  
B Cell ◽  
Cancer Patients ◽  
Tumor Immunity ◽  
Elevated Serum ◽  
T Cell Exhaustion ◽  
Cell Exhaustion

Abstract Abstract 143 IL-12 induces IFN-g production and contributes to anti-tumor immunity. However, administration of IL-12 in cancer patients has resulted in a limited clinical benefit. In follicular B-cell lymphoma (FL), a clinical trial of IL-12 in combination with rituximab showed a lower response rate in patients treated with the combination than in patients treated with rituximab alone (Clin Cancer Res 2006), suggesting that, in contrast to the observations in vitro or in vivo in mice, IL-12 actually plays a detrimental role in FL patients. Recently, a type of immune response, termed “ T cell exhaustion” describing a condition in which T cells exhibit reduced differentiation, proliferation, and effector function, has been shown to impair anti-tumor immunity and result in disease progression. TIM-3, a family member of T-cell immunoglobulin and mucin domian-containing proteins, inhibits TH1-mediated immune response and promotes immunological tolerance. A recent study has suggested that TIM-3 may play an important role in mediating T cell exhaustion. However, the biological and clinical relevance of TIM-3 in cancers remains completely unknown. In this study, we determined whether T cell exhaustion exists in the tumor microenvironment, whether IL-12 contributes to T cell exhaustion, and whether TIM-3-mediated T cell exhaustion impacts patient outcome in FL. We found that serum IL-12 levels were elevated in FL patients compared to healthy individuals (median: 0.50 ng/ml, n=30 vs 0.32 ng/ml, n=22; p= 0.03) and that elevated serum IL-12 levels were associated with a poor outcome in these patients when treated with rituximab alone as initial therapy. Using 0.56 ng/ml as a cutoff, patients with serum IL-12 levels of greater than 0.56 ng/ml had a significantly shorter time to progression than patients with IL-12 levels less than 0.56 ng/ml (12 months versus 40 months; p=0.001). Both lymphoma B cells and monocytes were able to produce IL-12 and contributed to elevated serum levels of IL-12 in FL. Importantly, we found that IL-12 strongly induced TIM-3 expression in a dose-dependent manner. Endogenous production of IL-12 by lymphoma B cells and monocytes was capable of regulating TIM-3 expression on T cells from FL. As a consequence, TIM-3 was highly expressed on a subset of T cells from PBMCs or lymph nodes from FL patients while its expression was negligible or moderate on T cells from normal PBMCs or benign lymph nodes, respectively. The number of TIM-3-expressing T cells accounted for approximately 32% and 39% of CD4+ or CD8+ T cells in biopsy specimens and 6.2% and 6.7% in peripheral blood of FL patients. TIM-3+ T cells, co-expressed with PD-1, exhibited a reduced ability to proliferate and decreased cytokine production compared to TIM-3- T cells. Similarly, IL-12-induced TIM-3+ T cells gradually lost the capacity to produce cytokines over a period of time. These results suggest that TIM-3-expressing T cells are functionally exhausted. In addition, TIM-3+ T cells were prone to apoptotic induction by its ligand galectin (Gal) -9. The phosphorylation of p38 was higher in TIM-3+ T cells compared to TIM-3- T cells when exposed to Gal-9, suggesting MAPK pathway was involved in Gal-9-mediated apoptosis of TIM-3+ T cells. Finally, increased numbers of intratumoral TIM-3-expressing cells were associated with a higher histological grade, higher LDH levels and a poor survival in FL patients. Taken together, these results indicate that IL-12, in contrast to its role in augmenting immune response through IFN-g, induces T cell exhaustion by upregulating TIM-3 expression. We further demonstrated that lymphoma B cells produce IL-12 thereby contributing to T cell exhaustion by promoting TIM-3 expression on intratumoral T cells. Impairment of anti-tumor immunity due to T cell exhaustion induced by the IL-12-TIM-3 pathway may account for the observation that high levels of serum IL-12 and increased number of TIM-3+CD4+ T cells correlate with a worse outcome in FL patients. These findings not only reveal a novel IL-12-TIM-3 pathway that plays an important role in impairing tumor immunity and detrimentally affecting prognosis in FL patients, but may have therapeutic potential for cancer patients. Disclosures: No relevant conflicts of interest to declare.

In Situ Vaccination with a TLR9 Agonist and Anti-OX40 Antibody Leads to Tumor Regression and Induces Abscopal Responses in Murine Lymphoma

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 1847-1847 ◽  
Author(s):  
Idit sagiv-Barfi ◽  
Debra K Czerwinski ◽  
Ronald Levy
Keyword(s):  
Immune Response ◽  
T Cells ◽  
Research Funding ◽  
Tumor Regression ◽  
Lung Metastases ◽  
Mammary Glands ◽  
Low Doses ◽  
Phase I Clinical Trials ◽  
Systemic Injection ◽  
Tlr9 Agonist

Abstract Background: Toll-like receptors (TLRs) are components of the innate immune system that recognize pathogen-associated molecular patterns on bacterial, fungal, or viral pathogens. Intratumoral (IT) injection of unmethylated CG-enriched oligodeoxynucleotide (CpG), a TLR9 agonist, results in local tumor eradication but on its own is not able to induce a systemic anti-tumor immune response. OX40 is a potent costimulatory receptor that can potentiate the action of conventional T cells leading to their proliferation, effector function and survival, but can also inhibit or kill T regulatory cells by ADCC. In previous preclinical studies systemic injection of OX40 agonists increased antitumor immunity and improved survival. Scientific question: Does local injection of both CpG and low doses of an anti-OX40 agonistic antibody trigger a systemic anti-tumor immune response? Results: We implanted the A20 lymphoma tumor bilaterally on opposite sides of the abdomen. After tumors were established we administered microgram quantities of CpG and anti-OX40 antibody into the tumor on one side and monitored both the injected and the uninjected tumor sites. This treatment resulted in both a local and an abscopal effect on the contralateral, untreated tumor. In addition, the animals were protected from a second challenge with A20 cells. This anti-tumor effect was T cell dependent, since depletion of either CD4+ or CD8+ T cells abrogated the therapeutic effect. There was no evidence of toxicity or autoimmunity in the treated animals. To examine the potential of this maneuver to treat spontaneous, non-transplanted cancers we chose the mouse mammary tumor model- FVB/N-Tg(MMTV-PyVT)634Mul/J. These animals all develop invasive breast cancer tumors in all of their mammary glands by 12 weeks of age. Injections of CpG and anti-OX40 antibody into the first arising tumor not only prevented its growth but significantly reduced the incidence and outgrowth of subsequent tumors at un-injected susceptible mammary glands and reduced the number of lung metastases. Significance: TLR9 agonists and anti-OX40 antibodies are currently under clinical development for cancer treatment. We show here that combining anti-OX40 antibody with a TLR9 agonist at a single established tumor is sufficient to trigger a systemic anti-tumor response able to eradicate tumor at distant sites in both transplantable and spontaneously occurring oncogene-driven murine tumors. This anti-tumor effect was long lasting, specific and required T cells. Impact: Our current results suggest that CpG and anti-OX40 are sufficient to induce fully protective and curative anti-tumor immune responses, even in spontaneously arising cancer. Anti-OX40 and CpG are both currently in phase-I clinical trials as single agents. Our results provide the rationale for testing these agents clinically in combination as described here, injected locally in low doses in order to induce therapeutic anti-lymphoma immunity. Disclosures Levy: Kite Pharma: Consultancy; Five Prime Therapeutics: Consultancy; Innate Pharma: Consultancy; Beigene: Consultancy; Corvus: Consultancy; Dynavax: Research Funding; Pharmacyclics: Research Funding.

scholarly journals Characterization of IL-10-producing neutrophils in cattle infected with Ostertagia ostertagi

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Lei Li ◽  
Hongbin Si ◽  
Shu-Wei Wu ◽  
Jonatan Orangel Mendez ◽  
Dante Zarlenga ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cells ◽  
T Cell ◽  
B Cells ◽  
Immune Responses ◽  
Cd4 T Cells ◽  
Lymphoid Tissues ◽  
Dependent Manner ◽  
Ostertagia Ostertagi ◽  
Mhc Ii

AbstractIL-10 is a master regulator of immune responses, but its cellular source and function in cattle during the initial phase of immune priming have not been well established. Despite a massive B cell response in the abomasal draining lymph nodes in Ostertagia ostertagi (OO)-infected cattle, protective immunity is slow to develop, and partial protection requires years of repeated exposure. In addressing this problem, our initial hypothesis was that B cells produce IL-10 that downregulates the host protective immune response. However, our results showed that neutrophils made up the majority of IL-10-producing cells in circulation and in secondary lymphoid tissues, particularly the spleen (80%). Conversely, IL-10-producing B cells were rare. In addition, approximately 10% to 20% of the neutrophils in the blood and spleen expressed MHC II and were IL-10 negative, suggesting that neutrophils could also participate in antigen presentation. In vitro investigation of bovine neutrophils revealed that exposure thereof to OO extract increased IL-10 and MHC II expression in these cells in a dose-dependent manner, consistent with IL-10+/MHC II+ neutrophils detected in cattle shortly after experimental OO infection. Co-culture of untreated neutrophils with anti-CD3 antibody (Ab)-stimulated CD4+ T cells led to enhanced T cell activation; also, IL-10 depletion with neutralizing Ab enhanced the stimulatory function of neutrophils. OO extract depressed neutrophil stimulation of CD4+ T cells in the presence of IL-10-neutralizing Ab, suggesting that OO utilizes both IL-10-dependent and independent mechanisms to manipulate the bovine immune response. Finally, contact and viability were required for T cell-stimulatory neutrophil function. This report, to the best of our knowledge, is the first to demonstrate that neutrophil-derived IL-10 is directly involved in T cell regulation in cattle. Our data suggest that neutrophils and neutrophil-derived IL-10 are co-opted by nematode parasites and other pathogens to attenuate host immune responses and facilitate pathogen survival.

scholarly journals B cells imprint adoptively transferred CD8+ T cells with enhanced tumor immunity

2022 ◽  
Vol 10 (1) ◽  
pp. e003078
Author(s):  
Aubrey S Smith ◽  
Hannah M Knochelmann ◽  
Megan M Wyatt ◽  
Guillermo O Rangel Rivera ◽  
Amalia M Rivera-Reyes ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
Tumor Immunity ◽  
Ex Vivo ◽  
Antitumor Efficacy ◽  
High Dose ◽  
Tlr Agonists ◽  
Tlr9 Agonist

BackgroundAdoptive T cell transfer (ACT) therapy improves outcomes in patients with advanced malignancies, yet many individuals relapse due to the infusion of T cells with poor function or persistence. Toll-like receptor (TLR) agonists can invigorate antitumor T cell responses when administered directly to patients, but these responses often coincide with toxicities. We posited that TLR agonists could be repurposed ex vivo to condition T cells with remarkable potency in vivo, circumventing TLR-related toxicity.MethodsIn this study we investigated how tumor-specific murine CD8+ T cells and human tumor infiltrating lymphocytes (TILs) are impacted when expanded ex vivo with the TLR9 agonist CpG.ResultsHerein we reveal a new way to reverse the tolerant state of adoptively transferred CD8+ T cells against tumors using TLR-activated B cells. We repurposed the TLR9 agonist, CpG, commonly used in the clinic, to bolster T cell—B cell interactions during expansion for ACT. T cells expanded ex vivo from a CpG-treated culture demonstrated potent antitumor efficacy and prolonged persistence in vivo. This antitumor efficacy was accomplished without in vivo administration of TLR agonists or other adjuvants of high-dose interleukin (IL)-2 or vaccination, which are classically required for effective ACT therapy. CpG-conditioned CD8+ T cells acquired a unique proteomic signature hallmarked by an IL-2RαhighICOShighCD39low phenotype and an altered metabolic profile, all reliant on B cells transiently present in the culture. Likewise, human TILs benefitted from expansion with CpG ex vivo, as they also possessed the IL-2RαhighICOShighCD39low phenotype. CpG fostered the expansion of potent CD8+ T cells with the signature phenotype and antitumor ability via empowering a direct B–T cell interaction. Isolated B cells also imparted T cells with the CpG-associated phenotype and improved tumor immunity without the aid of additional antigen-presenting cells or other immune cells in the culture.ConclusionsOur results demonstrate a novel way to use TLR agonists to improve immunotherapy and reveal a vital role for B cells in the generation of potent CD8+ T cell-based therapies. Our findings have immediate implications in the clinical treatment of advanced solid tumors.

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