Correlation of Cytotoxic Function with the Expression of Natural Killer (NK) Cell Markers: CD69, Killer Inhibitory Receptors (KIR2DL-p70/KIR2DS-p50), and Cytoplasmic Perforin and IFNγ

Objective.To investigate natural killer (NK) cell proportions, NK cell cytotoxicity, and interleukin 18 (IL-18) expression, in patients with adult-onset Still’s disease (AOSD).Methods.Forty-five patients with AOSD (active = 22, inactive = 23) and 32 healthy controls were included. The proportions of NK cells among peripheral blood mononuclear cells were assessed by flow cytometry. IL-18 and IL-18-binding protein (IL-18BP) concentrations were measured by ELISA. Twenty-four patients with AOSD and 18 controls were examined for cytotoxic activity of NK cells by co-incubating NK cells with NK-sensitive K562 cells. The association of NK cell function with clinical and laboratory measures was investigated.Results.The proportions of NK cells were significantly lower in patients with active AOSD than in patients with inactive disease and controls. NK cell cytotoxic function was significantly lower in patients with AOSD than in controls. NK cell proportions and cytotoxic functions were reexamined in 11 and 6 patients, respectively, after treatment. Low NK cell proportion and cytotoxic dysfunction were improved with clinical improvements of the patients. IL-18 and IL-18BP levels were much higher in patients with active AOSD than in controls. NK cell cytotoxic functions were consistently low and IL-18 and IL-18BP levels were constantly high in patients with AOSD, regardless of disease activity.Conclusion.Low NK cell proportion, defective cytotoxic function, and elevated IL-18 levels may be significant features of AOSD. After resolution of the acute phase, low NK cell proportion was recovered and NK cell cytolytic function was restored along with clinical improvement. These findings possibly contribute to immunologic abnormalities in AOSD.

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Killer inhibitory receptors in natural killer and T lymphocytes

Mechanisms of Tumor Escape from the Immune Response ◽

10.1201/9781482265149-12 ◽

2002 ◽

pp. 236-252

Author(s):

Lorenzo Moretta ◽

Maria Cristina Mingari ◽

Roberto Biassoni ◽

Cristina Bottino ◽

Daniela Pende ◽

...

Keyword(s):

T Lymphocytes ◽

Natural Killer ◽

Inhibitory Receptors ◽

Killer Inhibitory Receptors

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Slaying the Trojan Horse: Natural Killer Cells Exhibit Robust Anti-HIV-1 Antibody-Dependent Activation and Cytolysis against Allogeneic T Cells

Journal of Virology ◽

10.1128/jvi.02461-14 ◽

2014 ◽

Vol 89 (1) ◽

pp. 97-109 ◽

Cited By ~ 31

Author(s):

Shayarana L. Gooneratne ◽

Jonathan Richard ◽

Wen Shi Lee ◽

Andrés Finzi ◽

Stephen J. Kent ◽

...

Keyword(s):

T Cells ◽

Nk Cells ◽

Natural Killer ◽

Nk Cell ◽

Target Cells ◽

Dependent Manner ◽

Inhibitory Receptors ◽

Cell Responses ◽

Anti Hiv ◽

Hiv 1

ABSTRACTMany attempts to design prophylactic human immunodeficiency virus type 1 (HIV-1) vaccines have focused on the induction of neutralizing antibodies (Abs) that block infection by free virions. Despite the focus on viral particles, virus-infected cells, which can be found within mucosal secretions, are more infectious than free virus bothin vitroandin vivo. Furthermore, assessment of human transmission couples suggests infected seminal lymphocytes might be responsible for a proportion of HIV-1 transmissions. Although vaccines that induce neutralizing Abs are sought, only some broadly neutralizing Abs efficiently block cell-to-cell transmission of HIV-1. As HIV-1 vaccines need to elicit immune responses capable of controlling both free and cell-associated virus, we evaluated the potential of natural killer (NK) cells to respond in an Ab-dependent manner to allogeneic T cells bearing HIV-1 antigens. This study presents data measuring Ab-dependent anti-HIV-1 NK cell responses to primary and transformed allogeneic T-cell targets. We found that NK cells are robustly activated in an anti-HIV-1 Ab-dependent manner against allogeneic targets and that tested target cells are subject to Ab-dependent cytolysis. Furthermore, the educated KIR3DL1+NK cell subset from HLA-Bw4+individuals exhibits an activation advantage over the KIR3DL1−subset that contains both NK cells educated through other receptor/ligand combinations and uneducated NK cells. These results are intriguing and important for understanding the regulation of Ab-dependent NK cell responses and are potentially valuable for designing Ab-dependent therapies and/or vaccines.IMPORTANCENK cell-mediated anti-HIV-1 antibody-dependent functions have been associated with protection from infection and disease progression; however, their role in protecting from infection with allogeneic cells infected with HIV-1 is unknown. We found that HIV-1-specific ADCC antibodies bound to allogeneic cells infected with HIV-1 or coated with HIV-1 gp120 were capable of activating NK cells and/or trigging cytolysis of the allogeneic target cells. This suggests ADCC may be able to assist in preventing infection with cell-associated HIV-1. In order to fully utilize NK cell-mediated Ab-dependent effector functions, it might also be important that educated NK cells, which hold the highest activation potential, can become activated against targets bearing HIV-1 antigens and expressing the ligands for self-inhibitory receptors. Here, we show that with Ab-dependent stimulation, NK cells expressing inhibitory receptors can mediate robust activation against targets expressing the ligands for those receptors.

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Nonstochastic Coexpression of Activation Receptors on Murine Natural Killer Cells

Journal of Experimental Medicine ◽

10.1084/jem.191.8.1341 ◽

2000 ◽

Vol 191 (8) ◽

pp. 1341-1354 ◽

Cited By ~ 97

Author(s):

Hamish R.C. Smith ◽

Hubert H. Chuang ◽

Lawrence L. Wang ◽

Margarita Salcedo ◽

Jonathan W. Heusel ◽

...

Keyword(s):

Natural Killer Cells ◽

Nk Cells ◽

Natural Killer ◽

Nk Cell ◽

Inhibitory Receptors ◽

Antigen Receptors ◽

Killer Cells ◽

Histocompatibility Complex ◽

Nk Cell Cytotoxicity

Murine natural killer cells (NK) express lectin-like activation and inhibitory receptors, including the CD94/NKG2 family of receptors that bind Qa-1, and the Ly-49 family that recognizes major histocompatibility complex class I molecules. Here, we demonstrate that cross-linking of NK cells with a new specific anti–Ly-49H mAb induced NK cell cytotoxicity and cytokine production. Ly-49H is expressed on a subset of NK cells and can be coexpressed with Ly-49 inhibitory receptors. However, unlike Ly-49 inhibitory receptors, Ly-49H is not detectable on naive splenic CD3+ T cells, indicating that Ly-49H may be an NK cell–specific activation receptor. In further contrast to the stochastically expressed Ly-49 inhibitory receptors, Ly-49H is preferentially expressed with the Ly-49D activation receptor, and expression of both Ly-49H and Ly-49D is augmented on NK cells that lack receptors for Qa-1 tetramers. On developing splenic NK1.1+ cells, Ly-49D and Ly-49H are expressed later than the inhibitory receptors. These results directly demonstrate that Ly-49H activates primary NK cells, and suggest that expression of Ly-49 activation receptors by NK cells may be specifically regulated on NK cell subsets. The simultaneous expression of multiple activation receptors by individual NK cells contrasts with that of T cell antigen receptors and is relevant to the role of NK cells in innate immunity.

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Evidence for Killing of Mesenchymal Stem Cells (MSC) by Autologous Natural Killer Lymphocytes.

Blood ◽

10.1182/blood.v104.11.1290.1290 ◽

2004 ◽

Vol 104 (11) ◽

pp. 1290-1290 ◽

Cited By ~ 1

Author(s):

Alessandro Poggi ◽

Anna-Maria Massaro ◽

Simone Negrini ◽

Ivana Pierri ◽

Manuela Balocco ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

T Lymphocytes ◽

Nk Cells ◽

Natural Killer ◽

Viral Infections ◽

Nk Cell ◽

Cell Lineage ◽

Culture Conditions ◽

Inhibitory Receptors

Abstract In this study, Mesenchymal Stem Cells (MSC) were obtained from bone marrow of 10 patients suffering from acute myeloid leukemia (AML), six M0/1 two M2, and two M5 (according to the FAB classification), 8 out of 10 in post-chemotherapy complete remission. These cells differentiated into adipocytes or osteoblasts under appropriate culture conditions. MSC were CD44+, CD73a+ CD73b+ CD105+, beta1 integrin+, ICAM1+, HLA-I+, HLA-II+ (variable proportions), CD45−, CD31−, CD34− and they constitutively expressed the stress-inducible MHC-related molecules MIC-A and the UL16 (induced at the surface of cells infected by cytomegalovirus) binding protein ULBP3. These molecules are reported ligands for the NKG2D receptor expressed by natural killer (NK) and CD8+ T lymphocytes, effector cells that are thought to play a role in host defence against tumors. NK cells have also been shown to regulate normal differentiation of hemopoietic precursor into the myeloid or lymphoid cell lineage. Moreover, it has been stated that NK cells are not able to damage autologous cells, as they receive negative signals through inhibitory receptors, including killer Ig-like receptors (KIR) or C-type lectin inhibitory receptors (CLIR), which bind to HLA-I discrete alleles. Surprisingly, we found that autologous IL2-activated, but not freshly isolated, NK cells lysed MSC, while T lymphocytes did not kill self or non-self MSC. Binding of ICAM-1 expressed by MSC to its receptor, the integrin LFA-1, expressed by NK cells plays a key role in MSC/NK interaction. More importantly, NKG2D/MICA and/or NKG2D/ULBP3 engagement is responsible for the delivery of lethal hit. Conversely, it appears that HLA-I molecules do not protect MSC from NK cell-mediated injury. Taken together, these data suggest that NK cells, when activated as it may occur during the first response to viral infections, are able to eliminate MSC, thus altering the normal interactions with hemopoietic precursors and possibly affecting their differentiation. This mechanism might also contribute to the development of aberrant precursors as observed in acute leukaemias.

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Anti-natural Killer Inhibitory Receptors in Elderly Patients with Acute Myeloid Leukaemia

European Oncology & Haematology ◽

10.17925/eoh.2010.06.1.86 ◽

2010 ◽

Vol 06 (01) ◽

pp. 86

Author(s):

Norbert Vey ◽

Daniel Olive ◽

◽

Keyword(s):

Acute Myeloid Leukaemia ◽

Myeloid Leukaemia ◽

Natural Killer ◽

Cell Function ◽

Nk Cell ◽

Killer Cell ◽

Single Agent ◽

Inhibitory Receptors ◽

Leukaemic Cells ◽

Acute Myeloid

Treatment with anti-killer-cell immunoglobulin-like receptor (KIR) monoclonal antibody (mAb) is a new approach aimed at harnessing the antileukaemic potential of natural killer (NK) cells for the treatment of acute myeloid leukaemia (AML). NK cell antitumour activity is regulated by a balance between activating and inhibitory receptors (KIR). 1-7F9/IPH2101 is a fully human immunoglobulin G4 (IgG4) mAb that binds to inhibitory KIR and blocks binding with its ligand (human leukocyte antigen C [HLA-C] molecule) on leukaemic cells.In vitro,and in a surrogatein vivomodel in mice, treatment with 1-7F9/IPH2101 was able to induce NK cell activation and cytotoxicity against leukaemic cells. Patients with AML often display abnormal NK cell function, while evidence of an impact of NK cell status on AML outcome has been reported in allogeneic transplantation. 1-7F9/IPH2101 is currently under clinical investigation in patients with AML. This article reviews the mechanisms of NK cell antileukaemic activity and its role and defects in AML. Currently available data on the pre-clinical and clinical development of 1-7F9/IPH2101 are presented, and the rationale for its future use as a single agent or in combination is discussed.

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Natural Killer Cell Inhibitory Receptors Block Actin Cytoskeleton-dependent Recruitment of 2B4 (CD244) to Lipid Rafts

Journal of Experimental Medicine ◽

10.1084/jem.20020427 ◽

2002 ◽

Vol 197 (1) ◽

pp. 77-85 ◽

Cited By ~ 95

Author(s):

Carsten Watzl ◽

Eric O. Long

Keyword(s):

Actin Cytoskeleton ◽

Natural Killer ◽

Lipid Rafts ◽

Cell Activation ◽

Nk Cell ◽

Killer Cell ◽

General Mechanism ◽

Target Cells ◽

Inhibitory Receptors ◽

Detergent Resistant Membrane

A dynamic balance of positive and negative signals regulates target cell lysis by natural killer (NK) cells upon engagement of a variety of different activation receptors and of inhibitory receptors that recruit the tyrosine phosphatase SHP-1. However, the step at which activation signals are blocked by SHP-1 is not known. We have been using activation receptor 2B4 (CD244) to study the influence of inhibitory receptors on NK cell activation. Engagement of inhibitory receptors by HLA class I on target cells blocks phosphorylation of 2B4, placing the inhibitory step at the level, or upstream of 2B4 phosphorylation. Here we show that phosphorylated 2B4, after engagement with either antibodies or target cells that express the 2B4 ligand, is found exclusively in a detergent-resistant membrane fraction that contains lipid rafts. Integrity of lipid rafts was essential for phosphorylation and activating function of 2B4. Coengagement of inhibitory receptors blocked 2B4 phosphorylation and 2B4 association with detergent-resistant membranes, indicating that inhibitory receptors function upstream of raft-dependent signals. Recruitment of 2B4 into detergent-resistant membrane fractions and 2B4 phosphorylation were dependent on actin polymerization. Blocking actin cytoskeleton-dependent raft recruitment of different receptors may be a general mechanism by which inhibitory receptors control NK cell activation.

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Natural Killer Cell Diversity in Viral Infection: Why and How Much?

Pathogens and Immunity ◽

10.20411/pai.v1i1.142 ◽

2016 ◽

Vol 1 (1) ◽

pp. 165 ◽

Cited By ~ 9

Author(s):

Catherine A. Blish

Keyword(s):

Natural Killer ◽

Cell Function ◽

Nk Cell ◽

Expression Patterns ◽

Killer Cell ◽

Inhibitory Receptors ◽

Cell Repertoire ◽

Cell Diversity ◽

Repertoire Diversity ◽

Functional Consequences

Natural killer cells are a diverse group of innate lymphocytes that are specialized to rapidly respond to cancerous or virus-infected cells. NK cell function is controlled by the integration of signals from activating and inhibitory receptors expressed at the cell surface. Variegated expression patterns of these activating and inhibitory receptors at the single cell level leads to a highly diverse NK cell repertoire. Here I review the factors that influence NK cell repertoire diversity and its functional consequences for our ability to fight viruses.

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Activating Natural Killer Cell Receptors, Selectins, and Inhibitory Siglecs Recognize Ebolavirus Glycoprotein

Journal of Innate Immunity ◽

10.1159/000517628 ◽

2021 ◽

pp. 1-13

Author(s):

Mostafa Jarahian ◽

Katharina Marstaller ◽

Nadine Banna ◽

Roshanak Ahani ◽

Mohammad Hossein Etemadzadeh ◽

...

Keyword(s):

Immune System ◽

Natural Killer ◽

Nk Cell ◽

Lentiviral Vector ◽

Killer Cell ◽

Inhibitory Receptors ◽

Binding Studies ◽

Immune Effector ◽

Cell Receptors ◽

Surface Molecules

Expression of the extensively glycosylated Ebolavirus glycoprotein (EBOV-GP) induces physical alterations of surface molecules and plays a crucial role in viral pathogenicity. Here we investigate the interactions of EBOV-GP with host surface molecules using purified EBOV-GP, EBOV-GP-transfected cell lines, and EBOV-GP-pseudotyped lentiviral particles. Subsequently, we wanted to examine which receptors are involved in this recognition by binding studies to cells transfected with the EBOV-GP as well as to recombinant soluble EBOV-GP. As the viral components can also bind to inhibitory receptors of immune cells (e.g., Siglecs, TIM-1), they can even suppress the activity of immune effector cells. Our data show that natural killer (NK) cell receptors NKp44 and NKp46, selectins (CD62E/P/L), the host factors DC-SIGNR/DC-SIGN, and inhibitory Siglecs function as receptors for EBOV-GP. Our results show also moderate to strong avidity of homing receptors (P-, L-, and E-selectin) and DC-SIGNR/DC-SIGN to purified EBOV-GP, to cells transfected with EBOV-GP, as well as to the envelope of a pseudotyped lentiviral vector carrying the EBOV-GP. The concomitant activation and inhibition of the immune system exemplifies the evolutionary antagonism between the immune system and pathogens. Altogether these interactions with activating and inhibitory receptors result in a reduced NK cell-mediated lysis of EBOV-GP-expressing cells. Modulation of these interactions may provide new strategies for treating infections caused by this virus.

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Natural Killer Cells in Cancer Immunotherapy

Annual Review of Cancer Biology ◽

10.1146/annurev-cancerbio-030518-055653 ◽

2019 ◽

Vol 3 (1) ◽

pp. 77-103 ◽

Cited By ~ 29

Author(s):

Jeffrey S. Miller ◽

Lewis L. Lanier

Keyword(s):

T Cells ◽

Nk Cells ◽

Cancer Immunotherapy ◽

Natural Killer ◽

Nk Cell ◽

Inhibitory Receptors ◽

Antigen Specificity ◽

Infected Cells ◽

Missing Self ◽

Fail Safe

Natural killer (NK) cells have evolved to complement T and B cells in host defense against pathogens and cancer. They recognize infected cells and tumors using a sophisticated array of activating, costimulatory, and inhibitory receptors that are expressed on NK cell subsets to create extensive functional diversity. NK cells can be targeted to kill with exquisite antigen specificity by antibody-dependent cellular cytotoxicity. NK and T cells share many of the costimulatory and inhibitory receptors that are currently under evaluation in the clinic for cancer immunotherapy. As with T cells, genetic engineering is being employed to modify NK cells to specifically target them to tumors and to enhance their effector functions. As the selective pressures exerted by immunotherapies to augment CD8+T cell responses may result in loss of MHC class I, NK cells may provide an important fail-safe to eliminate these tumors by their capacity to eliminate tumors that are “missing self.”

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