scholarly journals Effects of β-adrenergic receptor activation, cholera toxin and forskolin on human natural killer cell function

1990 ◽  
Vol 272 (2) ◽  
pp. 327-331 ◽  
Author(s):  
M M Whalen ◽  
A D Bankhurst
Keyword(s):  
Nk Cells ◽  
Natural Killer ◽  
Cholera Toxin ◽  
Cell Function ◽  
Nk Cell ◽  
Killer Cell ◽  
K562 Cells ◽  
Receptor Activation ◽  
Tumour Cells ◽  
Human Natural Killer Cell

Membranes from highly purified natural killer (NK) cells were ADP-ribosylated by treatment with cholera toxin (CTX). CTX resulted in a single band of specific 32P incorporation at Mr 43,600. CTX treatment of intact NK cells caused a 9-fold increase in cyclic AMP (cAMP) concentrations. Pretreatment of NK cells with CTX diminished their ability to lyse K562 tumour cells by up to 79%. Forskolin treatment elevated NK cell cAMP levels 8-fold and decreased lysis of K562 cells by up to 45%. Adrenaline and isoprenaline (isoproterenol) both inhibited lysis of K562 cells by approx. 35% and elevated cAMP by at least 2.5-fold, and their inhibition of lysis was reversed by propranolol. These data suggest that the stimulatory guanine-nucleotide-binding protein GS coupled to beta-adrenergic receptors is involved in transducing signals which inhibit NK cell lysis of tumour cells. CTX and forskolin also diminish the ability of NK cells to bind K562 cells (binding is necessary for lysis). This suggests that the NK-cell receptor(s) for the tumour cell may be altered as a consequence of cAMP-mediated events or by activation of GS.

scholarly journals SDF-1α Reduces Human Natural Killer Cell Cytotoxicity against Chronic Myelogenous Leukemia K562 Cells

2019 ◽  
Author(s):  
Alireza Mardomi ◽  
Hadi Hossein-Nataj ◽  
Narjes Jafari ◽  
Nabiallah Mohammadi ◽  
Saeid Abediankenari
Keyword(s):  
Nk Cells ◽  
Natural Killer ◽  
Peripheral Blood ◽  
Nk Cell ◽  
Killer Cell ◽  
K562 Cells ◽  
Myelogenous Leukemia ◽  
Mrna Levels ◽  
Human Natural Killer Cell ◽  
Natural Killer Cell Cytotoxicity

Stromal cell-derived factor-1 alpha (SDF-1α) has been shown to be up-regulated in a variety of malignancies. So that, its expression is associated with poor prognosis and invasiveness. Natural killer (NK) cells are important effector cells against virus-infected and transformed cells. Especially they play a key role in tumor immune surveillance. Whereas it was not well understood whether SDF-1α modulates anti-tumor immune response or not, the purpose of the present study was to investigate the effect of SDF-1α on the cytotoxic properties of peripheral blood NK cells. Human peripheral blood NK cells were freshly isolated using MACSxpess system and cultured in the presence or absence of recombinant human SDF-1α or SDF-1α plus CXCR4 antagonist, AMD3100. CD107a degranulation assay was conducted through the co-culture of NK cells with K562 cells. The percentage of CD107a positive cells was assessed by flowcytometry. Effect of SDF-1α was also examined on the mRNA levels of NKG2A and NKG2D as indicator examples of NK cell inhibitory and activating receptors, respectively. SDF-1α significantly decreased the degranulation activity of NK cells (p=0.04). The mRNA content of NKG2D was down-regulated under the influence of SDF-1α (p=0.03). Moreover, AMD3100 exhibited a trend in recovering the NKG2D mRNA level to its un-treated state (p=0.05).  The present study reveals that SDF-1α has a negative impact on NK cell activity and might is involved in tumor immune-suppression. Thus, it can be concluded that microenvironment manipulations targeting SDF-1α may reinforce current cancer therapies by disturbing one of the immune-suppressive axes in the cancerous milieu. 

scholarly journals Natural killer cells suppress human erythroid stem cell proliferation in vitro

Blood ◽  
1984 ◽  
Vol 63 (2) ◽  
pp. 260-269 ◽  
Author(s):  
KF Mangan ◽  
ME Hartnett ◽  
SA Matis ◽  
A Winkelstein ◽  
T Abo
Keyword(s):  
Stem Cell ◽  
Natural Killer Cell ◽  
Nk Cells ◽  
Natural Killer ◽  
Nk Cell ◽  
Killer Cell ◽  
Human Natural Killer Cell ◽  
Percoll Density Gradient Centrifugation

Abstract To determine the role of natural killer (NK) cells in the regulation of human erythropoiesis, we studied the effects of NK-enriched cell populations on the in vitro proliferation of erythroid stem cells at three different levels of maturation (day 14 blood BFU-E, day 5–6 marrow CFU-E, and day 10–12 marrow BFU-E). NK cells were enriched from blood by Percoll density gradient centrifugation and by fluorescence- activated cell sorting (FACS), using the human natural killer cell monoclonal antibody, HNK-1. The isolated enriched fractions were cocultured with autologous nonadherent marrow cells or blood null cells and erythropoietin in a methylcellulose erythroid culture system. Cells from low-density Percoll fractions (NK-enriched cells) were predominantly large granular lymphocytes with cytotoxic activity against K562 targets 6–10-fold greater than cells obtained from high- density Percoll fractions (NK-depleted cells). In coculture with marrow nonadherent cells (NA) at NK:NA ratios of 2:1, NK-enriched cells suppressed day 5–6 CFU-E to 62% (p less than 0.025) of controls, whereas NK-depleted cells slightly augmented CFU-E to 130% of controls (p greater than 0.05). In contrast, no suppression of day 10–12 marrow BFU-E was observed employing NK-enriched cells. The NK CFU-E suppressor effects were abolished by complement-mediated lysis of NK-enriched cells with the natural killer cell antibody, HNK-1. Highly purified HNK- 1+ cells separated by FACS suppressed marrow CFU-E to 34% (p less than 0.025) and marrow BFU-E to 41% (p less than 0.025) of controls. HNK- cells had no significant effect on either BFU-E or CFU-E growth. NK- enriched cells were poor stimulators of day 14 blood BFU-E in comparison to equal numbers of NK-depleted cells or T cells isolated by E-rosetting (p less than 0.01). Interferon boosting of NK-enriched cells abolished their suboptimal burst-promoting effects and augmented their CFU-E suppressor effects. These studies provide evidence for a potential regulatory role of NK cells in erythropoiesis. The NK suppressor effect is maximal at the level of the mature erythroid stem cell CFU-E. These findings may explain some hypoproliferative anemias that develop in certain NK cell-activated states.

Hemostatic Factors Contribute to Tumor Cell Metastatic Potential by a Mechanism Linked to Natural Killer Cell Function.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 690-690 ◽  
Author(s):  
Joseph S. Palumbo ◽  
Kathryn E. Talmage ◽  
Jessica V. Massari ◽  
Christine M. La Jeunesse ◽  
Matthew J. Flick ◽  
...  
Keyword(s):  
Natural Killer Cell ◽  
Tumor Cell ◽  
Nk Cells ◽  
Natural Killer ◽  
Platelet Activation ◽  
Cell Function ◽  
Nk Cell ◽  
Killer Cell ◽  
Metastatic Potential ◽  
Natural Killer Cell Function

Abstract A linkage between hemostatic system components and tumor cell metastatic potential has been well established, but the underlying mechanism(s) by which various circulating and cell-associated coagulation factors and platelets promote tumor cell dissemination remains to be fully defined. One potential mechanism by which tumor cell-associated microthrombi might enhance metastatic potential is by interfering with the cytolytic elimination of tumor cell emboli by natural killer (NK) cells. In order to explore this hypothesis, we studied tumor dissemination in mice lacking either fibrinogen or Gαq, a G protein critical for platelet activation. Comparative studies of experimental lung metastasis in control and Gαq−/− mice showed that loss of platelet activation resulted in a two-orders-of-magnitude decrease in pulmonary metastatic foci formed by either Lewis lung carcinoma or B16 melanoma. The difference in metastatic success was not the result of differences in tumor growth rate, as tumors transplanted into the dorsal subcutis of Gαq−/− and wildtype animals grew at similar rates. Rather, tumor cell fate analyses using radiolabeled tumor cells showed that the survival of tumor cells within the lung was significantly improved in mice that retained platelet activation function relative to Gαq−/− mice with a profound platelet activation defect. In order to examine the potential interplay between platelet activation and natural killer cell function, we compared pulmonary tumor cell survival in cohorts of control and Gαq−/− mice immuno-depleted of NK cells with an anti-asialo GM1 antibody. Remarkably, platelet function was no longer a determinant of metastatic potential in mice lacking NK cells. Given that fibrin(ogen) is also an established determinant of metastatic success we explored whether the influence of this key hemostatic factor on tumor cell dissemination was also mechanistically-coupled to natural killer cell function. We interbred fibrinogen-deficient mice with Gz-Ly49A transgenic mice known to have a constitutive deficit in NK cells. In those cohorts of mice with normal NK cells, we affirmed the earlier finding that fibrinogen deficiency resulted in a significant diminution in metastatic potential. However, consistent with our findings in mice with defective platelet activation, fibrinogen was found to no longer be a determinant of metastatic potential in mice lacking NK cells. These data establish another important link between innate immune surveillance and the hemostatic system. Further, it appears that at least one mechanism by which tumor cell-associated microthrombi increase metastatic potential is by restricting NK cell-mediated tumor cell elimination. Given that NK cell cytotoxicity requires direct contact with any target cell, one attractive model presently being explored is that tumor cell-associated platelets physically block NK cell access to tumor cell emboli.

scholarly journals The PD-1/PD-L1 axis modulates the natural killer cell versus multiple myeloma effect: a therapeutic target for CT-011, a novel monoclonal anti–PD-1 antibody

Blood ◽  
2010 ◽  
Vol 116 (13) ◽  
pp. 2286-2294 ◽  
Author(s):  
Don M. Benson ◽  
Courtney E. Bakan ◽  
Anjali Mishra ◽  
Craig C. Hofmeister ◽  
Yvonne Efebera ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Immune Response ◽  
Nk Cells ◽  
Natural Killer ◽  
Tumor Cells ◽  
Cell Function ◽  
Nk Cell ◽  
Killer Cell ◽  
Cell Immune Response ◽  
Cell Versus

Abstract T-cell expression of programmed death receptor-1 (PD-1) down-regulates the immune response against malignancy by interacting with cognate ligands (eg, PD-L1) on tumor cells; however, little is known regarding PD-1 and natural killer (NK) cells. NK cells exert cytotoxicity against multiple myeloma (MM), an effect enhanced through novel therapies. We show that NK cells from MM patients express PD-1 whereas normal NK cells do not and confirm PD-L1 on primary MM cells. Engagement of PD-1 with PD-L1 should down-modulate the NK-cell versus MM effect. We demonstrate that CT-011, a novel anti–PD-1 antibody, enhances human NK-cell function against autologous, primary MM cells, seemingly through effects on NK-cell trafficking, immune complex formation with MM cells, and cytotoxicity specifically toward PD-L1+ MM tumor cells but not normal cells. We show that lenalidomide down-regulates PD-L1 on primary MM cells and may augment CT-011's enhancement of NK-cell function against MM. We demonstrate a role for the PD-1/PD-L1 signaling axis in the NK-cell immune response against MM and a role for CT-011 in enhancing the NK-cell versus MM effect. A phase 2 clinical trial of CT-011 in combination with lenalidomide for patients with MM should be considered.

scholarly journals ATP secreted by endothelial cells blocks CX3CL1-elicited natural killer cell chemotaxis and cytotoxicity via P2Y11 receptor activation

Blood ◽  
2010 ◽  
Vol 116 (22) ◽  
pp. 4492-4500 ◽  
Author(s):  
Stefania Gorini ◽  
Giulia Callegari ◽  
Giulia Romagnoli ◽  
Caterina Mammi ◽  
Domenico Mavilio ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Nk Cells ◽  
Natural Killer ◽  
Vascular Injury ◽  
Nk Cell ◽  
Umbilical Vein ◽  
Killer Cell ◽  
Receptor Activation ◽  
Human Coronary Artery ◽  
Uridine Triphosphate

Abstract Endothelial cells (ECs) represent a major source of actively secreted adenosine triphosphate (ATP). Natural killer (NK) cells can mediate vascular injury in several pathologic conditions, including cytomegalovirus infection and vascular leak syndrome. We studied NK-cell expression of P2 receptors and the role of these nucleotide receptors in the regulation of endothelial-NK cell cross-talk. NK cells from healthy subjects expressed P2Y1,2,4,6,11,12,13,14 and P2X1,4,5,6,7 receptors. NK cells stimulated with ATP, but not uridine triphosphate, increased intracellular Ca2+ and chemokinesis. Moreover, ATP, but not uridine triphosphate, inhibited NK chemotaxis in response to CX3CL1, whereas chemotaxis to CXCL12 was increased. CX3CL1 elicited killing of human umbilical vein ECs and human coronary artery ECs by NK cells. However, in the presence of ATP, CX3CL1 failed to stimulate killing of ECs. Such inhibitory effect was lost on exogenous addition of the ATP-hydrolyzing enzyme apyrase or by pharmacologic inhibition of the P2Y11R, and correlated with increased intracellular cyclic adenosine monophosphate concentrations induced by ATP or other P2Y11R agonists, including NAD+. Extracellular ATP regulates NK-cell cytotoxicity via P2Y11R activation, protecting ECs from CX3CL1-elicited NK cell–mediated killing. These findings point out the P2Y11R as a potential target for pharmacologic intervention aimed at reducing NK-mediated vascular injury.

scholarly journals The Axl/Gas6 pathway is required for optimal cytokine signaling during human natural killer cell development

Blood ◽  
2009 ◽  
Vol 113 (11) ◽  
pp. 2470-2477 ◽  
Author(s):  
Il-Kyoo Park ◽  
Chiara Giovenzana ◽  
Tiffany L. Hughes ◽  
Jianhua Yu ◽  
Rossana Trotta ◽  
...  
Keyword(s):  
Nk Cells ◽  
Natural Killer ◽  
Nk Cell ◽  
Killer Cell ◽  
Absolute Number ◽  
Interferon Γ ◽  
Cell Development ◽  
Cytokine Signaling ◽  
Human Natural Killer Cell ◽  
Human Cd34

Interleukin-15 (IL-15) is essential for natural killer (NK) cell differentiation. In this study, we assessed whether the receptor tyrosine kinase Axl and its ligand, Gas6, are involved in IL-15–mediated human NK differentiation from CD34+ hematopoietic progenitor cells (HPCs). Blocking the Axl-Gas6 interaction with a soluble Axl fusion protein (Axl-Fc) or the vitamin K inhibitor warfarin significantly diminished the absolute number and percentage of CD3−CD56+ NK cells derived from human CD34+ HPCs cultured in the presence of IL-15, probably resulting in part from reduced phosphorylation of STAT5. In addition, CD3−CD56+ NK cells derived from culture of CD34+ HPCs with IL-15 and Axl-Fc had a significantly diminished capacity to express interferon-γ or its master regulator, T-BET. Culture of CD34+ HPCs in the presence of c-Kit ligand and Axl-Fc resulted in a significant decrease in the frequency of NK precursor cells responding to IL-15, probably the result of reduced c-Kit phosphorylation. Collectively, our data suggest that the Axl/Gas6 pathway contributes to normal human NK-cell development, at least in part via its regulatory effects on both the IL-15 and c-Kit signaling pathways in CD34+ HPCs, and to functional NK-cell maturation via an effect on the master regulatory transcription factor T-BET.

scholarly journals Screening for Active Compounds Targeting Human Natural Killer Cell Activation Identifying Daphnetin as an Enhancer for IFN-γ Production and Direct Cytotoxicity

2021 ◽  
Vol 12 ◽  
Author(s):  
Baige Yao ◽  
Qinglan Yang ◽  
Yao Yang ◽  
Yana Li ◽  
Hongyan Peng ◽  
...  
Keyword(s):  
Nk Cells ◽  
Natural Killer ◽  
Cell Activation ◽  
Nk Cell ◽  
Killer Cell ◽  
Mtor Signaling ◽  
Human Natural Killer Cell ◽  
Active Compounds ◽  
Direct Cytotoxicity ◽  
Ifn Γ

Natural killer (NK) cells are a potent weapon against tumor and viral infection. Finding active compounds with the capacity of enhancing NK cell effector functions will be effective to develop new anti-cancer drugs. In this study, we initially screened 287 commercially available active compounds by co-culturing with peripheral blood mononuclear cells (PBMCs). We found that five compounds, namely, Daphnetin, MK-8617, LW6, JIB-04, and IOX1, increased the IFN-γ+ NK cell ratio in the presence of IL-12. Further studies using purified human primary NK cells revealed that Daphnetin directly promoted NK cell IFN-γ production in the presence of IL-12 but not IL-15, while the other four compounds acted on NK cells indirectly. Daphnetin also improved the direct cytotoxicity of NK cells against tumor cells in the presence of IL-12. Through RNA-sequencing, we found that PI3K-Akt-mTOR signaling acted as a central pathway in Daphnetin-mediated NK cell activation in the presence of IL-12. This was further confirmed by the finding that both inhibitors of PI3K-Akt and its main downstream signaling mTOR, LY294002, and rapamycin, respectively, can reverse the increase of IFN-γ production and cytotoxicity in NK cells promoted by Daphnetin. Collectively, we identify a natural product, Daphnetin, with the capacity of promoting human NK cell activation via PI3K-Akt-mTOR signaling in the presence of IL-12. Our current study opens up a new potential application for Daphnetin as a complementary immunomodulator for cancer treatments.

scholarly journals Glycosylation Affects Ligand Binding and Function of the Activating Natural Killer Cell Receptor 2B4 (CD244) Protein

2011 ◽  
Vol 286 (27) ◽  
pp. 24142-24149 ◽  
Author(s):  
Stefanie Margraf-Schönfeld ◽  
Carolin Böhm ◽  
Carsten Watzl
Keyword(s):  
Ligand Binding ◽  
Nk Cells ◽  
Natural Killer ◽  
Cell Function ◽  
Nk Cell ◽  
Negative Impact ◽  
Killer Cell ◽  
Target Cells ◽  
Functional Assay ◽  
Cell Responses

2B4 (CD244) is an important activating receptor for the regulation of natural killer (NK) cell responses. Here we show that 2B4 is heavily and differentially glycosylated in primary human NK cells and NK cell lines. The differential glycosylation could be attributed to sialic acid residues on N- and O-linked carbohydrates. Using a recombinant fusion protein of the extracellular domain of 2B4, we demonstrate that N-linked glycosylation of 2B4 is essential for the binding to its ligand CD48. In contrast, sialylation of 2B4 has a negative impact on ligand binding, as the interaction between 2B4 and CD48 is increased after the removal of sialic acids. This was confirmed in a functional assay system, where the desialylation of NK cells or the inhibition of O-linked glycosylation resulted in increased 2B4-mediated lysis of CD48-expressing tumor target cells. These data demonstrate that glycosylation has an important impact on 2B4-mediated NK cell function and suggest that regulated changes in glycosylation during NK cell development and activation might be involved in the regulation of NK cell responses.

scholarly journals Bortezomib down-regulates the cell-surface expression of HLA class I and enhances natural killer cell–mediated lysis of myeloma

Blood ◽  
2008 ◽  
Vol 111 (3) ◽  
pp. 1309-1317 ◽  
Author(s):  
Jumei Shi ◽  
Guido J. Tricot ◽  
Tarun K. Garg ◽  
Priyangi A. Malaviarachchi ◽  
Susann M. Szmania ◽  
...  
Keyword(s):  
Cell Surface ◽  
Nk Cells ◽  
Natural Killer ◽  
Cell Function ◽  
Nk Cell ◽  
Killer Cell ◽  
Surface Expression ◽  
Class I ◽  
Cell Surface Expression ◽  
Significant Activity

AbstractHuman leukocyte antigen class I molecules expressed by tumor cells play a central role in the regulation of natural killer (NK) cell–mediated immune responses. The proteasome inhibitor bortezomib has demonstrated significant activity in multiple myeloma (MM). We hypothesized that treatment of MM with bortezomib results in the reduction of cell-surface expression of class I and thereby sensitizes MM to NK cell–mediated lysis. Here we report that bortezomib down-regulates class I in a time- and dose-dependent fashion on all MM cell lines and patient MM cells tested. Downregulation of class I can also be induced in vivo after a single dose of 1.0 mg/m2 bortezomib. Bortezomib significantly enhances the sensitivity of patient myeloma to allogeneic and autologous NK cell–mediated lysis. Further, the level of decrease in class I expression correlates with increased susceptibility to lysis by NK cells. Clinically relevant bortezomib concentrations do not affect NK-cell function. Our findings have clear therapeutic implications for MM and other NK cell–sensitive malignancies in the context of both allogeneic and autologous adoptively transferred NK cells.

scholarly journals Age-dependent susceptibility to a viral disease due to decreased natural killer cell numbers and trafficking

2010 ◽  
Vol 207 (11) ◽  
pp. 2369-2381 ◽  
Author(s):  
Min Fang ◽  
Felicia Roscoe ◽  
Luis J. Sigal
Keyword(s):  
Nk Cells ◽  
Natural Killer ◽  
Cell Function ◽  
Nk Cell ◽  
Killer Cell ◽  
Viral Disease ◽  
Viral Diseases ◽  
Cell Responses ◽  
Loss Of Resistance ◽  
Age Dependent

Although it is well known that aged hosts are generally more susceptible to viral diseases than the young, specific dysfunctions of the immune system directly responsible for this increased susceptibility have yet to be identified. We show that mice genetically resistant to mousepox (the mouse parallel of human smallpox) lose resistance at mid-age. Surprisingly, this loss of resistance is not a result of intrinsically defective T cell responses. Instead, the primary reason for the loss of resistance results from a decreased number of total and mature natural killer (NK) cells in the blood and an intrinsic impairment in their ability to migrate to the lymph node draining the site of infection, which is essential to curb systemic virus spread. Hence, our work links the age-dependent increase in susceptibility to a viral disease to a specific defect of NK cells, opening the possibility of exploring treatments to improve NK cell function in the aged with the goal of enhancing their resistance to viral diseases.

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