scholarly journals Oncolytic virus treatment differentially affects the CD56dim and CD56bright NK cell subsets in vivo and regulates a spectrum of human NK cell activity

2020 ◽  
Author(s):  
Michelle Wantoch ◽  
Erica B. Wilson ◽  
Alastair P. Droop ◽  
Sarah L. Phillips ◽  
Matt Coffey ◽  
...  
Keyword(s):  
Nk Cells ◽  
Oncolytic Virus ◽  
Nk Cell ◽  
Direct Action ◽  
Cell Activity ◽  
Type I ◽  
Dependent Manner ◽  
Nk Cell Activity ◽  
Tumour Immunity

AbstractNatural killer (NK) cells protect against intracellular infection and cancer. These properties are exploited in oncolytic virus (OV) therapy, where anti-viral responses enhance anti-tumour immunity. We have analysed the mechanism by which reovirus, an oncolytic dsRNA virus, modulates human NK cell activity. Reovirus activates NK cells in a type I interferon (IFN-I) dependent manner, resulting in STAT1 and STAT4 signalling in both CD56dim and CD56bright NK cell subsets. Gene expression profiling revealed the dominance of IFN-I responses and identified induction of genes associated with NK cell cytotoxicity and cell cycle progression, with distinct responses in the CD56dim and CD56bright subsets. However, reovirus treatment, acting via IFN-I, inhibited NK cell proliferative responses to IL-15 and was associated with reduced AKT signalling. In vivo, human CD56dim and CD56bright NK cells responded with similar kinetics to reovirus treatment, but CD56bright NK cells were transiently lost from the peripheral circulation at the peak of the IFN-I response, suggestive of their redistribution to secondary lymphoid tissue. These results show that reovirus modulates a spectrum of NK cell activity in vivo, encompassing direct action on tumour cells and the regulation of adaptive immunity. Such activity is likely to mirror NK cell responses to natural viral infection.

scholarly journals Pro-apoptotic caspase deficiency reveals a cell-extrinsic mechanism of NK cell regulation

2021 ◽  
Author(s):  
Tayla M. Olsen ◽  
Wei Hong Tan ◽  
Arne C. Knudsen ◽  
Anthony Rongvaux
Keyword(s):  
Cell Death ◽  
Nk Cells ◽  
Nk Cell ◽  
Apoptotic Cell ◽  
Type I ◽  
Dependent Manner ◽  
Apoptosis Pathway ◽  
A Cell

AbstractRegulated cell death is essential for the maintenance of cellular and tissue homeostasis. In the hematopoietic system, genetic defects in apoptotic cell death generally produce the accumulation of immune cells, inflammation and autoimmunity. In contrast, we found that genetic deletion of caspases of the mitochondrial apoptosis pathway reduces natural killer (NK) cell numbers and makes NK cells functionally defective in vivo and in vitro. Caspase deficiency results in constitutive activation of a type I interferon (IFN) response, due to leakage of mitochondrial DNA and activation of the cGAS/STING pathway. The NK cell defect in caspase-deficient mice is independent of the type I IFN response, but the phenotype is partially rescued by cGAS or STING deficiency. Finally, caspase deficiency alters NK cells in a cell-extrinsic manner. Type I IFNs and NK cells are two essential effectors of antiviral immunity, and our results demonstrate that they are both regulated in a caspase-dependent manner. Beyond caspase-deficient animals, our observations may have implications in infections that trigger mitochondrial stress and caspase-dependent cell death.

Azacytidine Compromises NK-Cell Activity in AML and MDS Patients Undergoing MRD-Based Pre-Emptive Treatment After Allogeneic Stem Cell Transplantation

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 4122-4122
Author(s):  
Katja Sockel ◽  
Claudia Schönefeldt ◽  
Sieghart Sopper ◽  
Martin Wermke ◽  
Marc Schmitz ◽  
...  
Keyword(s):  
Stem Cell ◽  
Stem Cell Transplantation ◽  
Nk Cells ◽  
Cell Function ◽  
Nk Cell ◽  
Cell Activity ◽  
Nk Cell Activity ◽  
Activating Receptors

Abstract Abstract 4122 The hypomethylating agent azacytidine (AZA) represents the standard treatment for many high-risk MDS and AML patients. While the clinical efficacy has been confirmed in several studies, the precise molecular mechanism of action has not been fully understood yet. Human NK-cells play an important role in the regulation of immune responses against malignant cells. Their function is controlled by a complex interplay of activating and inhibitory receptors - some of them being regulated by methylation of the respective genes. We, therefore explored, whether AZA modulates in vitro NK-cell function as well as in vivo during minimal-residual disease (MRD)-guided treatment of imminent relapse in MDS and AML patients treated within the prospective RELAZA trial (NCT00422890). Methods: After purifying NK-cells of healthy donors by MACS (magnetic cell sorting), NK-cells were exposed in vitro to different concentrations of AZA (100nM, 1μM, 3μM) with or without IL-2. In parallel, the NK-cell phenotype of patients (n=12) with AML or MDS, undergoing MRD-guided treatment with AZA after stem cell transplantation was monitored by FACS from peripheral blood samples on day 1, 5 and 7 of the first and second AZA cycle. All patients were still in complete haematological remission at the time of therapy. Results: In vitro, we observed a significant reduction (3,1% to 1,8% p=0.028) of the immature and cytokine-regulating CD56bright NK-cell subpopulation with increasing concentrations of AZA. There was a trend towards a reduced expression of the death-ligand TRAIL, the activating receptors NKG2D and NKp46 and for an increased expression of the inhibitory KIR CD158b1/b2, whereas we could not detect any changes in the expression of FAS-L, Perforin, Granzyme B, NKp30, NKp44, CD69, CD57, DNAM-1, CD16, and NKG2A-CD94. Confirmatory, we observed a significant decrease in the expression of TRAIL (p=0.003), NKG2D (p=0.03) and NKp46 (p=0.006) during AZA treatment in-vivo. Interestingly, these changes appeared to be reversible. The observed reduction of NK-cell activating receptors and TRAIL during AZA treatment correlated with a reduction or stable course of MRD in all analyzed patients. Conclusion: In summary these data suggest that the clinical effects of AZA are not mediated by enhancing NK-cell activity. In fact, the drug may have inhibitory effects on NK-cell function which should be considered when applying AZA in the post-transplant setting. Disclosures: Platzbecker: Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding.

Influence of in vivo hypobaric hypoxia on function of lymphocytes, neutrocytes, natural killer cells, and cytokines

1993 ◽  
Vol 74 (3) ◽  
pp. 1100-1106 ◽  
Author(s):  
M. Klokker ◽  
A. Kharazmi ◽  
H. Galbo ◽  
I. Bygbjerg ◽  
B. K. Pedersen
Keyword(s):  
Immune System ◽  
Nk Cells ◽  
Natural Killer ◽  
Nk Cell ◽  
Interleukin 2 ◽  
Cell Activity ◽  
Nk Cell Activity ◽  
Cd8 Cells ◽  
The Absolute

We have investigated the effects of short-term hypoxia in vivo on the human cellular immune system. Seven young healthy volunteers were placed in a decompression chamber (380 Torr) for 20 min with or without supplemental O2. The leukocyte concentration increased during hypobaric conditions because of an increased concentration of lymphocytes. The absolute and relative concentration of CD16+ natural killer (NK) cells increased markedly during hypoxia and returned to pretest values after 2 h of recovery. The NK cell activity of blood mononuclear cells (BMNC, %lysis/fixed no. of BMNC) boosted with interferon-alpha, interleukin-2 (IL-2), and indomethacin rose in parallel with unboosted NK cell activity during hypoxia. The percentage of CD4+ and CD8+ cells declined during hypoxia, whereas the absolute concentration of both CD8+ cells and CD14+ monocytes increased. Although the BMNC composition varied, the proliferative responses of BMNC after stimulation with phytohemagglutinin, purified derivative of tuberculin, and IL-2 did not change significantly. The in vitro production of interleukin-1 beta and IL-2 in supernatants obtained after stimulation of BMNC with phytohemagglutinin or lipopolysaccharide was not affected. The chemiluminescence response of neutrocytes increased 2 h after hypoxia. It was concluded that acute hypoxia induced marked alterations in the immune system and that the NK cells are especially sensitive to the hypoxic stimulus.

Influence of Neuroleptics on Cytotoxic Activity of Rat Natural Killer Cells

1998 ◽  
Vol 11 (2) ◽  
pp. 57-62
Author(s):  
A.J. Madej ◽  
J. Kowalski ◽  
D. Belowski ◽  
Z. S. Herman
Keyword(s):  
Cytotoxic Activity ◽  
Nk Cells ◽  
Nk Cell ◽  
Cell Activity ◽  
Nk Cell Activity ◽  
Vitro Experiment ◽  
In Vitro Experiment ◽  
In Vivo Experiment

The aim of the study was to evaluate the in vivo and in vitro effects of three neuroleptics (chlorpromazine, haloperidol, and sulpiride) on the activity of rat spleen NK cells. In the in vivo experiment, rats were injected with different intraperitoneal doses of neuroleptics given once, for 14 or 28 days. In the in vitro experiment rat spleen NK cells were cultured in medium containing two different concentrations of neuroleptics for three days. The cytotoxic activity of NK cells was evaluated by measuring 51Cr release from YAC-1 target cells after 4-hour incubation. We also measured, using fluorescein-labelled anti-NK monoclonal antibody, the percentage of NK cells in the splenocyte population before and after single intraperitoneal injections of neuroleptics. In the in vitro experiment, both haloperidol (1×10−5 M and 1×10−6 M) and sulpiride (1.5×10−3 M and 1.5×10−4 M) induced a statistically significant decrease in the cytotoxic activity of NK cells. The lower dose of chlorpromazine (6×10−6 M) decreased the cytotoxic activity of NK cells, while the higher dose (6×10−5 M) did not. In the in vivo experiment, both single and repeated doses of chlorpromazine (2 mg /kg /day), haloperidol (0.5 mg/kg/day) and sulpiride (50 mg/kg/day) increased NK cell activity. That effect reflected an increase in NK cell activity but not in the number of NK cells. The study has shown that the immunomodulatory effect of neuroleptics on NK cell activity depends mainly on drug concentrations and experimental conditions.

scholarly journals Augmentation of Cytolytic Activity in Murine Natural Killer Cells and Inhibition of Tumor Growth by the Ethanol Fraction of Oyster Extract

2016 ◽  
Vol 17 (1) ◽  
pp. 31-40 ◽  
Author(s):  
Kaito Sakaguchi ◽  
Ming Zhong ◽  
Saeko Kawai ◽  
Yoshio Shimizu ◽  
Eiichi Gohda
Keyword(s):  
Tumor Growth ◽  
Nk Cells ◽  
Natural Killer ◽  
Nk Cell ◽  
Cell Activity ◽  
Cytolytic Activity ◽  
Proteinase K ◽  
Nk Cell Activity

A reduced number and/or reduced activity of natural killer (NK) cells, which are important for defense against a variety of cancers and viral infections, occur under various stress conditions and in patients with various diseases. In this article, we report that the 30% to 50% ethanol precipitate of oyster extract (EPOE50) dose-dependently enhanced the activity of mouse spleen NK cells in vitro and in vivo. The activity of EPOE50 was eluted with a molecular weight of about 2000 by gel filtration and was inactivated by periodate but not by proteinase K. The activity of highly purified NK cells was also augmented by EPOE50 but not by oligodeoxyribonucleotide 1585, which mimics bacterial DNA. Administration of EPOE50 to mice stimulated splenic NK cell activity without a change in splenic NK cell populations. Although the proliferation of B16 tumor cells in vitro was slightly stimulated by EPOE50, the growth of B16 melanoma in vivo was dose-dependently suppressed by administration of EPOE50. Taken together, our results indicate that EPOE50 augmented NK cell activity and that its administration to mice inhibited tumor growth presumably through the activation of NK cells and also suggest that the active substance is a sugar-containing oligomer or polymer and is not of bacterial origin.

scholarly journals NK cells mediate clearance of CD8+ T cell–resistant tumors in response to STING agonists

2020 ◽  
Vol 5 (45) ◽  
pp. eaaz2738 ◽  
Author(s):  
Christopher J. Nicolai ◽  
Natalie Wolf ◽  
I-Chang Chang ◽  
Georgia Kirn ◽  
Assaf Marcus ◽  
...  
Keyword(s):  
T Cell ◽  
Nk Cells ◽  
Cell Activation ◽  
Nk Cell ◽  
Tumor Rejection ◽  
Tumor Control ◽  
Type I ◽  
Dependent Manner ◽  
Tumor Models

Several immunotherapy approaches that mobilize CD8+ T cell responses stimulate tumor rejection, and some, such as checkpoint blockade, have been approved for several cancer indications and show impressive increases in patient survival. However, tumors may evade CD8+ T cell recognition via loss of MHC molecules or because they contain few or no neoantigens. Therefore, approaches are needed to combat CD8+ T cell–resistant cancers. STING-activating cyclic dinucleotides (CDNs) are a new class of immune-stimulating agents that elicit impressive CD8+ T cell–mediated tumor rejection in preclinical tumor models and are now being tested in clinical trials. Here, we demonstrate powerful CDN-induced, natural killer (NK) cell–mediated tumor rejection in numerous tumor models, independent of CD8+ T cells. CDNs enhanced NK cell activation, cytotoxicity, and antitumor effects in part by inducing type I interferon (IFN). IFN acted in part directly on NK cells in vivo and in part indirectly via the induction of IL-15 and IL-15 receptors, which were important for CDN-induced NK activation and tumor control. After in vivo administration of CDNs, dendritic cells (DCs) up-regulated IL-15Rα in an IFN-dependent manner. Mice lacking the type I IFN receptor specifically on DCs had reduced NK cell activation and tumor control. Therapeutics that activate NK cells, such as CDNs, checkpoint inhibitors, NK cell engagers, and cytokines, may represent next-generation approaches to cancer immunotherapy.

scholarly journals Varicella-Zoster Virus and Herpes Simplex Virus 1 Differentially Modulate NKG2D Ligand Expression during Productive Infection

2015 ◽  
Vol 89 (15) ◽  
pp. 7932-7943 ◽  
Author(s):  
Tessa M. Campbell ◽  
Brian P. McSharry ◽  
Megan Steain ◽  
Barry Slobedman ◽  
Allison Abendroth
Keyword(s):  
Nk Cells ◽  
Nk Cell ◽  
Cell Activity ◽  
Nkg2d Ligand ◽  
Nk Cell Activity ◽  
Herpes Simplex Virus 1 ◽  
Varicella Zoster ◽  
Ligand Expression ◽  
Simplex Virus ◽  
Hsv 1

ABSTRACTNatural killer (NK) cell-deficient patients are particularly susceptible to severe infection with herpesviruses, especially varicella-zoster virus (VZV) and herpes simplex virus 1 (HSV-1). The critical role that NK cells play in controlling these infections denotes an intricate struggle for dominance between virus and NK cell antiviral immunity; however, research in this area has remained surprisingly limited. Our study addressed this absence of knowledge and found that infection with VZV was not associated with enhanced NK cell activation, suggesting that the virus uses specific mechanisms to limit NK cell activity. Analysis of viral regulation of ligands for NKG2D, a potent activating receptor ubiquitously expressed on NK cells, revealed that VZV differentially modulates expression of the NKG2D ligands MICA, ULBP2, and ULBP3 by upregulating MICA expression while reducing ULBP2 and ULBP3 expression on the surface of infected cells. Despite being closely related to VZV, infection with HSV-1 produced a remarkably different effect on NKG2D ligand expression. A significant decrease in MICA, ULBP2, and ULBP3 was observed with HSV-1 infection at a total cellular protein level, as well as on the cell surface. We also demonstrate that HSV-1 differentially regulates expression of an additional NKG2D ligand, ULBP1, by reducing cell surface expression while total protein levels are unchanged. Our findings illustrate both a striking point of difference between two closely related alphaherpesviruses, as well as suggest a powerful capacity for VZV and HSV-1 to evade antiviral NK cell activity through novel modulation of NKG2D ligand expression.IMPORTANCEPatients with deficiencies in NK cell function experience an extreme susceptibility to infection with herpesviruses, in particular, VZV and HSV-1. Despite this striking correlation, research into understanding how these two alphaherpesviruses interact with NK cells is surprisingly limited. Through examination of viral regulation of ligands to the activating NK cell receptor NKG2D, we reveal patterns of modulation by VZV, which were unexpectedly varied in response to regulation by HSV-1 infection. Our study begins to unravel the undoubtedly complex interactions that occur between NK cells and alphaherpesvirus infection by providing novel insights into how VZV and HSV-1 manipulate NKG2D ligand expression to modulate NK cell activity, while also illuminating a distinct variation between two closely related alphaherpesviruses.

scholarly journals Immunosurveillance of Cancer and Viral Infections with Regard to Alterations of Human NK Cells Originating from Lifestyle and Aging

Biomedicines ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 557
Author(s):  
Xuewen Deng ◽  
Hiroshi Terunuma ◽  
Mie Nieda
Keyword(s):  
Nk Cells ◽  
Viral Infections ◽  
Nk Cell ◽  
Healthy Lifestyle ◽  
Cell Activity ◽  
Nk Cell Activity ◽  
Effector Cells ◽  
Cell Dysfunction ◽  
Forest Bathing ◽  
Infected Cells

Natural killer (NK) cells are cytotoxic immune cells with an innate capacity for eliminating cancer cells and virus- infected cells. NK cells are critical effector cells in the immunosurveillance of cancer and viral infections. Patients with low NK cell activity or NK cell deficiencies are predisposed to increased risks of cancer and severe viral infections. However, functional alterations of human NK cells are associated with lifestyles and aging. Personal lifestyles, such as cigarette smoking, alcohol consumption, stress, obesity, and aging are correlated with NK cell dysfunction, whereas adequate sleep, moderate exercise, forest bathing, and listening to music are associated with functional healthy NK cells. Therefore, adherence to a healthy lifestyle is essential and will be favorable for immunosurveillance of cancer and viral infections with healthy NK cells.

scholarly journals Anti-tumor effects of RTX-240: an engineered red blood cell expressing 4-1BB ligand and interleukin-15

2021 ◽  
Author(s):  
Shannon L. McArdel ◽  
Anne-Sophie Dugast ◽  
Maegan E. Hoover ◽  
Arjun Bollampalli ◽  
Enping Hong ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Blood Cell ◽  
Nk Cells ◽  
Red Blood Cell ◽  
Safety Profile ◽  
Nk Cell ◽  
Cell Activity ◽  
In Vivo Studies

AbstractRecombinant agonists that activate co-stimulatory and cytokine receptors have shown limited clinical anticancer utility, potentially due to narrow therapeutic windows, the need for coordinated activation of co-stimulatory and cytokine pathways and the failure of agonistic antibodies to recapitulate signaling by endogenous ligands. RTX-240 is a genetically engineered red blood cell expressing 4-1BBL and IL-15/IL-15Rα fusion (IL-15TP). RTX-240 is designed to potently and simultaneously stimulate the 4-1BB and IL-15 pathways, thereby activating and expanding T cells and NK cells, while potentially offering an improved safety profile through restricted biodistribution. We assessed the ability of RTX-240 to expand and activate T cells and NK cells and evaluated the in vivo efficacy, pharmacodynamics and tolerability using murine models. Treatment of PBMCs with RTX-240 induced T cell and NK cell activation and proliferation. In vivo studies using mRBC-240, a mouse surrogate for RTX-240, revealed biodistribution predominantly to the red pulp of the spleen, leading to CD8 + T cell and NK cell expansion. mRBC-240 was efficacious in a B16-F10 melanoma model and led to increased NK cell infiltration into the lungs. mRBC-240 significantly inhibited CT26 tumor growth, in association with an increase in tumor-infiltrating proliferating and cytotoxic CD8 + T cells. mRBC-240 was tolerated and showed no evidence of hepatic injury at the highest feasible dose, compared with a 4-1BB agonistic antibody. RTX-240 promotes T cell and NK cell activity in preclinical models and shows efficacy and an improved safety profile. Based on these data, RTX-240 is now being evaluated in a clinical trial.

scholarly journals miR-1224 contributes to ischemic stroke-mediated natural killer cell dysfunction by targeting Sp1 signaling

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Yan Feng ◽  
Yan Li ◽  
Ying Zhang ◽  
Bo-Hao Zhang ◽  
Hui Zhao ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Nk Cells ◽  
Natural Killer ◽  
Brain Ischemia ◽  
Cell Activation ◽  
Nk Cell ◽  
Cell Activity ◽  
Passive Transfer ◽  
Immune Defense ◽  
Nk Cell Activity

Abstract Background Brain ischemia compromises natural killer (NK) cell-mediated immune defenses by acting on neurogenic and intracellular pathways. Less is known about the posttranscriptional mechanisms that regulate NK cell activation and cytotoxicity after ischemic stroke. Methods Using a NanoString nCounter® miRNA array panel, we explored the microRNA (miRNA) profile of splenic NK cells in mice subjected to middle cerebral artery occlusion. Differential gene expression and function/pathway analysis were applied to investigate the main functions of predicted miRNA target genes. miR-1224 inhibitor/mimics transfection and passive transfer of NK cells were performed to confirm the impact of miR-1224 in NK cells after brain ischemia. Results We observed striking dysregulation of several miRNAs in response to ischemia. Among those miRNAs, miR-1224 markedly increased 3 days after ischemic stroke. Transfection of miR-1224 mimics into NK cells resulted in suppression of NK cell activity, while an miR-1224 inhibitor enhanced NK cell activity and cytotoxicity, especially in the periphery. Passive transfer of NK cells treated with an miR-1224 inhibitor prevented the accumulation of a bacterial burden in the lungs after ischemic stroke, suggesting an enhanced immune defense of NK cells. The transcription factor Sp1, which controls cytokine/chemokine release by NK cells at the transcriptional level, is a predicted target of miR-1224. The inhibitory effect of miR-1224 on NK cell activity was blocked in Sp1 knockout mice. Conclusions These findings indicate that miR-1224 may serve as a negative regulator of NK cell activation in an Sp1-dependent manner; this mechanism may be a novel target to prevent poststroke infection specifically in the periphery and preserve immune defense in the brain.

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