ROLES OF PROGRAMMED DEATH LIGAND-1 (PDL-1) AND ANTIGEN-PRESENTING NATURAL KILLER (AP-NK) CELLS IN PROMOTING IMMUNOSUPPRESSIVE TUMOR MICROENVIRONMENT (TME) IN ORAL CANCER (OC)

2021 ◽  
Vol 132 (1) ◽  
pp. e49-e50
Author(s):  
N Vigneswaran ◽  
J Wu ◽  
R Shah ◽  
J Holland ◽  
S Narendran ◽  
...  
2020 ◽  
Vol 6 (1) ◽  
pp. 1-10
Author(s):  
Raudatul Janah

ABSTRAKMeningioma merupakan tumor yang paling umum terjadi pada sistem saraf pusat (SSP), berasal dari sel meningothelial lapisan arakhnoid. Programmed Death Ligand 1 (PD-L1) merupakan protein immune checkpoint yang akan menyebabkan imun antitumor tersupresi. Pada meningioma high grade, sel T regulator dan ekspresi PD-L1 meningkat yang disebabkan karena immunosuppressive tumor microenvironment sehingga tumor menjadi agresif. Tingkat ekspresi PD-L1 tidak ditetapkan dalam meningioma. Tergantung pada tingkat ekspresi, anti-PD-L1, mungkin merupakan pengobatan yang efektif untuk meningioma.Kata Kunci : meningioma, PD-L1, Anti PD-L1


2021 ◽  
Vol 12 ◽  
Author(s):  
Benedikt Jacobs ◽  
Veronika Gebel ◽  
Lukas Heger ◽  
Victoria Grèze ◽  
Hansjörg Schild ◽  
...  

Cellular therapy has entered the daily clinical life with the approval of CAR T cell therapeutics and dendritic cell (DCs) vaccines in the US and the EU. In addition, numerous other adoptive cellular products, including natural killer (NK) cells, are currently evaluated in early phase I/ II clinical trials for the treatment of cancer patients. Despite these promising accomplishments, various challenges remain to be mastered in order to ensure sustained therapeutic success. These include the identification of strategies by which tumor cells escape the immune system or establish an immunosuppressive tumor microenvironment (TME). As part of the innate immune system, DCs and NK cells are both present within the TME of various tumor entities. While NK cells are well known for their intrinsic anti-tumor activity by their cytotoxicity capacities and the secretion of pro-inflammatory cytokines, the role of DCs within the TME is a double-edged sword as different DC subsets have been described with either tumor-promoting or -inhibiting characteristics. In this review, we will discuss recent findings on the interaction of DCs and NK cells under physiological conditions and within the TME. One focus is the crosstalk of various DC subsets with NK cells and their impact on the progression or inhibition of tumor growth. In addition, we will provide suggestions to overcome the immunosuppressive outcome of the interaction of DCs and NK cells within the TME.


2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A834-A834
Author(s):  
Xue Yao ◽  
Sandro Matosevic

BackgroundThe effectiveness of natural killer (NK) cell-based immunotherapy against solid tumors is limited by the lack of specific antigens and the immunosuppressive tumor microenvironment (TME). Glioblastoma multiforme (GBM) is one such heavily immunosuppressive tumor that has been particularly hard to target and remains without a viable treatment. The development of novel approaches to enhance the efficacy of NK cells against GBM is urgently needed. NK cell engagers (NKCE) have been developed to enhance the efficacy of NK cell therapy.MethodsTo improve the clinical efficacy of NK cell therapy, we are developing a new generation of multi-specific killer engagers, which consists of a neoantigen-targeting moiety, together with cytokine and chemokine-producing domains. Neoantigens are new antigens formed specifically in tumor cells due to genome mutations, making them highly specific tools to target tumor cells. Our engager has been designed to target Wilms' tumor-1 (WT-1), a highly specific antigen overexpressed in GBM among other solid tumors. This is done through the generation of an scFv specific targeting the complex of WT-1126-134/HLA-A*02:01 on the surface of GBM. On the NK cell side, the engager is designed to target the activating receptor NKp46. Incorporation of the cytokine IL-15 within the engager supports the maturation, persistence, and expansion of NK cells in vivo while favoring their proliferation and survival in the tumor microenvironment. Additionally, our data indicated that the chemokine CXCL10 plays an important role in the infiltration of NK cells into GBM, however, GBM tumors produce low levels of this chemokine. Incorporation of a CXCL10-producing function into our engager supports intratumoral NK cell trafficking by promoting, through their synthetic production, increased levels of CXCL10 locally in the tumor microenvironment.ResultsCollectively, this has resulted in a novel multifunctional NK cell engager, combining neoantigen-cytokine-chemokine elements fused to an activating domain-specific to NK cells, and we have investigated its ability to support and enhance NK cell-mediated cytotoxicity against solid tumors in vitro and in vivo against patient-derived GBM models. The multi-specific engager shows both high tumor specificity, as well as the ability to overcome NK cell dysfunction encountered in the GBM TME.ConclusionsWe hypothesize that taking advantage of our multi-functional engager, NK cells will exhibit superior ex vivo expansion, infiltration, and antitumor activity in the treatment of GBM and other solid tumors.


Cancers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 4037
Author(s):  
Pankaj Ahluwalia ◽  
Meenakshi Ahluwalia ◽  
Ashis K. Mondal ◽  
Nikhil S. Sahajpal ◽  
Vamsi Kota ◽  
...  

Non-small cell lung cancer (NSCLC) is a major subtype of lung cancer that accounts for almost 85% of lung cancer cases worldwide. Although recent advances in chemotherapy, radiotherapy, and immunotherapy have helped in the clinical management of these patients, the survival rate in advanced stages remains dismal. Furthermore, there is a critical lack of accurate prognostic and stratification markers for emerging immunotherapies. To harness immune response modalities for therapeutic benefits, a detailed understanding of the immune cells in the complex tumor microenvironment (TME) is required. Among the diverse immune cells, natural killer (NK cells) and dendritic cells (DCs) have generated tremendous interest in the scientific community. NK cells play a critical role in tumor immunosurveillance by directly killing malignant cells. DCs link innate and adaptive immune systems by cross-presenting the antigens to T cells. The presence of an immunosuppressive milieu in tumors can lead to inactivation and poor functioning of NK cells and DCs, which results in an adverse outcome for many cancer patients, including those with NSCLC. Recently, clinical intervention using modified NK cells and DCs have shown encouraging response in advanced NSCLC patients. Herein, we will discuss prognostic and predictive aspects of NK cells and DC cells with an emphasis on NSCLC. Additionally, the discussion will extend to potential strategies that seek to enhance the anti-tumor functionality of NK cells and DCs.


2019 ◽  
Vol 79 (16) ◽  
pp. 4149-4159 ◽  
Author(s):  
Renee Clift ◽  
Jennifer Souratha ◽  
Sheryl A. Garrovillo ◽  
Susan Zimmerman ◽  
Barbara Blouw

2020 ◽  
Vol 9 (6) ◽  
pp. 2077-2084 ◽  
Author(s):  
Nicolas Stocker ◽  
Béatrice Gaugler ◽  
Laure Ricard ◽  
Frédéric Vassoigne ◽  
Zora Marjanovic ◽  
...  

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 584-584
Author(s):  
Regina Gary ◽  
Simon Voelkl ◽  
Ralf Palmisano ◽  
Andreas Mackensen

Abstract Abstract 584 Specific T-cell responses are initiated by T-cell receptor (TCR) recognition of peptide-MHC-complexes on antigen presenting cells (APCs). Upon specific interaction of T cells with APCs T cells capture membrane fragments and surface molecules of APCs in a process termed trogocytosis. Exchange of membrane molecules/antigens between immune cells has been observed for a long time, but the mechanisms and functional consequences of these transfers remain unclear. Here, we demonstrate that human antigen-specific CD8+ T cells do acquire the co-inhibitory molecule programmed death ligand 1 (PD-L1) from mature monocyte-derived dendritic cells (mDC) and tumor cells in an antigen-specific manner. The kinetics of PD-L1 transfer revealed a maximal PD-L1 expression on antigen-specific T cells within 3–4 hours after co-incubation with antigen-pulsed APCs, being detectable up to 72 hours. Antigen-pulsed immature DCs were less effective in transfering surface molecules such as PD-L1 onto CD8+ T cells after antigen-specific recognition. Using a transwell system we could show that the acquisition of PD-L1 requires cell-cell contact. Furthermore, PD-L1 cannot be acquired by T cells from a lysate of mDCs. The transfer process is impaired after pretreatment of T cells with concanamycin A, a specific inhibitor of vacuolar ATPases, playing an important role in membrane trafficking. Moreover, fixation of DCs with glutaraldehyde completely abrogated the acquisition of PD-L1 on T cells suggesting that an active interaction between APCs and T cells is required for trogocytosis. Of importance, CD8+ T cells which acquired PD-L1 complexes, were able to induce apoptosis of neighbouring PD-1 expressing CD8+ T cells, that could be completely blocked by an anti-PD-L1 antibody. In summary our data demonstrate for the first time that human antigen-specific CD8+ T cells take up functionally active PD-L1 from APCs in an antigen-specific fashion, leading to apoptosis of PD-1 expressing T cells. The transfer of functionally active co-inhibitory molecules from APCs onto human CD8+ T cells may serve to limit clonal expansion of antigen-specific T-cell responses but may also play a major role for T-cell exhaustion in chronic infection and tumor immunosurveillance. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 3091-3091 ◽  
Author(s):  
Enli Liu ◽  
Yijiu Tong ◽  
Gianpietro Dotti ◽  
Barbara Savoldo ◽  
Muharrem Muftuoglu ◽  
...  

Abstract Natural killer (NK) cells are a major component of the innate immune system, possessing the ability to lyse their targets without the need for prior sensitization or specificity for antigen. Besides their classical role in providing potent antitumor and antiviral immunity, NK cells can reduce the risk of graft-versus-host disease (GVHD) by targeting host antigen-presenting cells, as well as activated alloreactive donor T cells, indicating that NK-mediated graft-versus-leukemia (GVL) responses may occur in the absence of GVHD. Although most groups have relied on autologous or adult peripheral blood donor-derived NK cells, we have studied umbilical CB as a potential source of NK cells because of their availability as an "off-the-shelf" frozen product and their potent preclinical activity against leukemia cells. To overcome the obstacle of limited numbers of NK cells in a single CB unit, we have established GMP-compliant conditions for the ex vivo expansion of clinically relevant doses of such cells. By using GMP grade K562-based artificial antigen-presenting cells (aAPCs), which express membrane-bound IL-21 (clone 9.mbIL21), to numerically expand highly functional and mature CB-derived NK cells. To further enhance the GVL effect independent of KIR-ligand mismatch, we have genetically modified human CB-derived NK cells with a retroviral vector, CAR19-CD28-zeta-2A-IL15 (CAR19/IL15), which incorporates the genes for CAR-CD19, IL-15 to enhance proliferation and survival, and the inducible caspase-9 molecule. CB-NK cells could be stably transduced with CAR19/IL15, proliferated efficiently in vitro and maintained superior effector function against CD19-expressing leukemia cell lines and primary CLL cells. Moreover, the effector functions of both NK-CAR and nontransduced NK cells against K562 were comparable, indicating that the genetic modification of CB-NK cells does not alter their intrinsic cytotoxicity against NK-sensitive targets. Because of concerns over autonomous, uncontrolled NK cell growth due to autocrine production of IL15, we also incorporated into our construct a suicide gene based on the inducible caspase-9 (IC9) gene. The addition of as little as 10 nM of the small molecule dimerizer CID AP20187 to cultures of iC9/CAR19/IL15+ NK cells induced apoptosis/necrosis of >60% of transgenic cells within 4 hours as assessed by annexin-V-7AAD staining. The infusion of CAR.CD19.IL15-transduced CB-NK cells into a NOD-SCID-gamma null model of lymphoblastic lymphoma (Raji model) resulted in impressive anti-tumor responses (Fig. 1). Moreover, adoptively infused CAR-transduced CB NK persisted for up to 70 days post-infusion (Fig. 2), supporting our hypothesis that IL-15 enhances the proliferation and survival of the engineered CB-NK cells. Based on these promising data, we now propose to manufacture a GMP-grade CAR19-CD28-zeta-2A-IL15 vector for a phase 1 dose escalation trial in patients with high risk B-cell leukemia. Disclosures Wierda: Celgene Corp.: Consultancy; Glaxo-Smith-Kline Inc.: Research Funding. Rezvani:Pharmacyclics: Research Funding.


2007 ◽  
Vol 75 (11) ◽  
pp. 5325-5337 ◽  
Author(s):  
Pablo Schierloh ◽  
Noemí Yokobori ◽  
Mercedes Alemán ◽  
Verónica Landoni ◽  
Laura Geffner ◽  
...  

ABSTRACT Tuberculous pleurisy allows the study of human cells at the site of active Mycobacterium tuberculosis infection. In this study, we found that among pleural fluid (PF) lymphocytes, natural killer (NK) cells are a major source of early gamma interferon (IFN-γ) upon M. tuberculosis stimulation, leading us to investigate the mechanisms and molecules involved in this process. We show that the whole bacterium is the best inducer of IFN-γ, although a high-molecular-weight fraction of culture filtrate proteins from M. tuberculosis H37Rv and the whole-cell lysate also induce its expression. The mannose receptor seems to mediate the inhibitory effect of mannosylated lipoarabinomannan, and Toll-like receptor 2 and 4 agonists activate NK cells but do not induce IFN-γ like M. tuberculosis does. Antigen-presenting cells (APC) and NK cells bind M. tuberculosis, and although interleukin-12 is required, it is not sufficient to induce IFN-γ expression, indicating that NK cell-APC contact takes place. Indeed, major histocompatibility complex class I, adhesion, and costimulatory molecules as well as NK receptors regulate IFN-γ induction. The signaling pathway is partially inhibited by dexamethasone and sensitive to Ca2+ flux and cyclosporine. Inhibition of p38 and extracellular-regulated kinase mitogen-activated protein kinase pathways reduces the number of IFN-γ+ NK cells. Phosphorylated p38 (p-p38) is detected in ex vivo PF-NK cells, and M. tuberculosis triggers p-p38 in PF-NK cells at the same time that binding between NK and M. tuberculosis reaches its maximum value. Thus, interplay between M. tuberculosis and NK cells/APC triggering IFN-γ would be expected to play a beneficial role in tuberculous pleurisy by helping to maintain a type 1 profile.


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