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Sample records for nk cells mediated

  1. Activation by SLAM Family Receptors Contributes to NK Cell Mediated "Missing-Self" Recognition.

    PubMed

    Alari-Pahissa, Elisenda; Grandclément, Camille; Jeevan-Raj, Beena; Leclercq, Georges; Veillette, André; Held, Werner

    2016-01-01

    Natural Killer (NK) cells attack normal hematopoietic cells that do not express inhibitory MHC class I (MHC-I) molecules, but the ligands that activate NK cells remain incompletely defined. Here we show that the expression of the Signaling Lymphocyte Activation Molecule (SLAM) family members CD48 and Ly9 (CD229) by MHC-I-deficient tumor cells significantly contributes to NK cell activation. When NK cells develop in the presence of T cells or B cells that lack inhibitory MHC-I but express activating CD48 and Ly9 ligands, the NK cells' ability to respond to MHC-I-deficient tumor cells is severely compromised. In this situation, NK cells express normal levels of the corresponding activation receptors 2B4 (CD244) and Ly9 but these receptors are non-functional. This provides a partial explanation for the tolerance of NK cells to MHC-I-deficient cells in vivo. Activating signaling via 2B4 is restored when MHC-I-deficient T cells are removed, indicating that interactions with MHC-I-deficient T cells dominantly, but not permanently, impair the function of the 2B4 NK cell activation receptor. These data identify an important role of SLAM family receptors for NK cell mediated "missing-self" reactivity and suggest that NK cell tolerance in MHC-I mosaic mice is in part explained by an acquired dysfunction of SLAM family receptors.

  2. Chicken NK cell receptors.

    PubMed

    Straub, Christian; Neulen, Marie-Luise; Sperling, Beatrice; Windau, Katharina; Zechmann, Maria; Jansen, Christine A; Viertlboeck, Birgit C; Göbel, Thomas W

    2013-11-01

    Natural killer cells are innate immune cells that destroy virally infected or transformed cells. They recognize these altered cells by a plethora of diverse receptors and thereby differ from other lymphocytes that use clonally distributed antigen receptors. To date, several receptor families that play a role in either activating or inhibiting NK cells have been identified in mammals. In the chicken, NK cells have been functionally and morphologically defined, however, a conclusive analysis of receptors involved in NK cell mediated functions has not been available. This is partly due to the low frequencies of NK cells in blood or spleen that has hampered their intensive characterization. Here we will review recent progress regarding the diverse NK cell receptor families, with special emphasis on novel families identified in the chicken genome with potential as chicken NK cell receptors.

  3. PD-1 mediates functional exhaustion of activated NK cells in patients with Kaposi sarcoma

    PubMed Central

    Beldi-Ferchiou, Asma; Lambert, Marion; Dogniaux, Stéphanie; Vély, Frédéric; Vivier, Eric; Olive, Daniel; Dupuy, Stéphanie; Levasseur, Frank; Zucman, David; Lebbé, Céleste; Sène, Damien; Hivroz, Claire; Caillat-Zucman, Sophie

    2016-01-01

    Programmed Death-1 (PD-1), an inhibitory receptor expressed by activated lymphocytes, is involved in regulating T- and B-cell responses. PD-1 and its ligands are exploited by a variety of cancers to facilitate tumor escape through PD-1-mediated functional exhaustion of effector T cells. Here, we report that PD-1 is upregulated on Natural Killer (NK) cells from patients with Kaposi sarcoma (KS). PD-1 was expressed in a sub-population of activated, mature CD56dimCD16pos NK cells with otherwise normal expression of NK surface receptors. PD-1pos NK cells from KS patients were hyporesponsive ex vivo following direct triggering of NKp30, NKp46 or CD16 activating receptors, or short stimulation with NK cell targets. PD-1pos NK cells failed to degranulate and release IFNγ, but exogenous IL-2 or IL-15 restored this defect. That PD-1 contributed to NK cell functional impairment and was not simply a marker of dysfunctional NK cells was confirmed in PD-1-transduced NKL cells. In vitro, PD-1 was induced at the surface of healthy control NK cells upon prolonged contact with cells expressing activating ligands, i.e. a condition mimicking persistent stimulation by tumor cells. Thus, PD-1 appears to plays a critical role in mediating NK cell exhaustion. The existence of this negative checkpoint fine-tuning NK activation highlights the possibility that manipulation of the PD-1 pathway may be a strategy for circumventing tumor escape not only from the T cell-, but also the NK-cell mediated immune surveillance. PMID:27662664

  4. PD-1 mediates functional exhaustion of activated NK cells in patients with Kaposi sarcoma.

    PubMed

    Beldi-Ferchiou, Asma; Lambert, Marion; Dogniaux, Stéphanie; Vély, Frédéric; Vivier, Eric; Olive, Daniel; Dupuy, Stéphanie; Levasseur, Frank; Zucman, David; Lebbé, Céleste; Sène, Damien; Hivroz, Claire; Caillat-Zucman, Sophie

    2016-11-08

    Programmed Death-1 (PD-1), an inhibitory receptor expressed by activated lymphocytes, is involved in regulating T- and B-cell responses. PD-1 and its ligands are exploited by a variety of cancers to facilitate tumor escape through PD-1-mediated functional exhaustion of effector T cells. Here, we report that PD-1 is upregulated on Natural Killer (NK) cells from patients with Kaposi sarcoma (KS). PD-1 was expressed in a sub-population of activated, mature CD56dimCD16pos NK cells with otherwise normal expression of NK surface receptors. PD-1pos NK cells from KS patients were hyporesponsive ex vivo following direct triggering of NKp30, NKp46 or CD16 activating receptors, or short stimulation with NK cell targets. PD-1pos NK cells failed to degranulate and release IFNγ, but exogenous IL-2 or IL-15 restored this defect. That PD-1 contributed to NK cell functional impairment and was not simply a marker of dysfunctional NK cells was confirmed in PD-1-transduced NKL cells. In vitro, PD-1 was induced at the surface of healthy control NK cells upon prolonged contact with cells expressing activating ligands, i.e. a condition mimicking persistent stimulation by tumor cells. Thus, PD-1 appears to plays a critical role in mediating NK cell exhaustion. The existence of this negative checkpoint fine-tuning NK activation highlights the possibility that manipulation of the PD-1 pathway may be a strategy for circumventing tumor escape not only from the T cell-, but also the NK-cell mediated immune surveillance.

  5. Human Dendritic Cells Mitigate NK-Cell Dysfunction Mediated by Nonselective JAK1/2 Blockade.

    PubMed

    Curran, Shane A; Shyer, Justin A; St Angelo, Erin T; Talbot, Lillian R; Sharma, Sneh; Chung, David J; Heller, Glenn; Hsu, Katharine C; Betts, Brian C; Young, James W

    2017-01-01

    Janus kinase (JAK) inhibitors have achieved positive responses in myeloproliferative neoplasms, but at the expense of decreased natural killer (NK) cell numbers and compromised function. Selective JAK2 inhibition may also have a role in preventing and treating graft-versus-host disease after allogeneic hematopoietic stem cell transplantation. Although JAK inhibitors can impair monocyte-derived dendritic cell (moDC) activation and function and suppress effector T-cell responses, the effects on NK cells and the relevant mechanisms remain undefined. Using common γc cytokines and distinct human dendritic cell (DC) subtypes, we compared the effects of a JAK2-specific (TG101348) with a less selective JAK1/2 (ruxolitinib) inhibitor on NK-cell activation and function. Ruxolitinib treatment completely blocked IL2, IL15, and DC-mediated STAT5 phosphorylation, along with the capacity of NK cells to secrete IFNγ or lyse NK cell-sensitive targets. Only NK-cell proliferation stimulated by moDCs resisted ruxolitinib treatment. In contrast, TG101348 treatment of stimulated NK cells resulted in far less functional compromise. TG101348 completely inhibited only soluble IL15-mediated STAT5 phosphorylation, which Langerhans-type DCs (LCs), presenting membrane-bound IL15 in trans, could salvage. These results demonstrate that ruxolitinib's nonselective inhibition of JAK1/2 results in profound NK-cell dysfunction by blocking downstream pSTAT5, hence providing a persuasive rationale for the development of selective JAK2 inhibitors for immunotherapeutic applications. Cancer Immunol Res; 5(1); 52-60. ©2016 AACR.

  6. Suppression of NK cell-mediated cytotoxicity against PRRSV-infected porcine alveolar macrophages in vitro.

    PubMed

    Cao, Jun; Grauwet, Korneel; Vermeulen, Ben; Devriendt, Bert; Jiang, Ping; Favoreel, Herman; Nauwynck, Hans

    2013-06-28

    The adaptive immunity against PRRSV has already been studied in depth, but only limited data are available on the innate immune responses against this pathogen. In the present study, we analyzed the interaction between porcine natural killer (NK) cells and PRRSV-infected primary porcine alveolar macrophages (PAMs), since NK cells are one of the most important components of innate immunity and PAMs are primary target cells of PRRSV infection. NK cytotoxicity assays were performed using enriched NK cells as effector cells and virus-infected or mock-inoculated PAMs as target cells. The NK cytotoxicity against PRRSV-infected PAMs was decreased starting from 6h post inoculation (hpi) till the end of the experiment (12 hpi) and was significantly lower than that against pseudorabies virus (PrV)-infected PAMs. UV-inactivated PRRSV also suppressed NK activity, but much less than infectious PRRSV. Furthermore, co-incubation with PRRSV-infected PAMs inhibited degranulation of NK cells. Finally, using the supernatant of PRRSV-infected PAMs collected at 12 hpi showed that the suppressive effect of PRRSV on NK cytotoxicity was not mediated by soluble factors. In conclusion, PRRSV-infected PAMs showed a reduced susceptibility toward NK cytotoxicity, which may represent one of the multiple evasion strategies of PRRSV.

  7. Two photon microscopy intravital study of DC-mediated anti-tumor response of NK cells

    NASA Astrophysics Data System (ADS)

    Caccia, Michele; Gorletta, Tatiana; Sironi, Laura; Zanoni, Ivan; Salvetti, Cristina; Collini, Maddalena; Granucci, Francesca; Chirico, Giuseppe

    2010-02-01

    Recent studies have demonstrated that dendritic cells (DCs) play a crucial role in the activation of Natural Killer cells (NKs) that are responsible for anti-tumor innate immune responses. The focus of this report is on the role of pathogen associated molecular pattern (PAMP) activated-DCs in inducing NK cell-mediated anti-tumor responses. Mice transplanted sub-cute (s.c.) with AK7 cells, a mesothelioma cell line sensitive to NK cell responses, are injected with fluorescent NK cells and DC activation is then induced by s.c. injection of Lipopolysaccharide (LPS). Using 4 dimensional tracking we follow the kinetic behavior of NK cells at the Draining Lymph-Node (DLN). As control, noninflammatory conditions are also evaluated. Our data suggest that NK cells are recruited to the DLN where they can interact with activated-DCs with a peculiar kinetic behavior: short lived interactions interleaved by rarer longer ones. We also found that the changes in the NK dynamic behavior in inflammatory conditions clearly affect relevant motility parameters such as the instantaneous and average velocity and the effective diffusion coefficient. This observation suggests that NK cells and activated-DCs might efficiently interact in the DLN, where cells could be activated. Therefore the interaction between activated-DCs and NK cells in DLN is not only a reality but it may be also crucial for the start of the immune response of the NKs.

  8. Taxanes enhance trastuzumab-mediated ADCC on tumor cells through NKG2D-mediated NK cell recognition.

    PubMed

    Di Modica, Martina; Sfondrini, Lucia; Regondi, Viola; Varchetta, Stefania; Oliviero, Barbara; Mariani, Gabriella; Bianchi, Giulia Valeria; Generali, Daniele; Balsari, Andrea; Triulzi, Tiziana; Tagliabue, Elda

    2016-01-05

    Recent clinical data indicate a synergistic therapeutic effect between trastuzumab and taxanes in neoadjuvantly treated HER2-positive breast cancer (BC) patients. In HER2+ BC experimental models and patients, we investigated whether this synergy depends on the ability of drug-induced stress to improve NK cell effectiveness and thus trastuzumab-mediated ADCC. HER2+ BC cell lines BT474 and MDAMB361 treated with docetaxel showed up-modulation of NK activator ligands both in vitro and in vivo, accompanied by a 15-40% increase in in vitro trastuzumab-mediated ADCC; antibodies blocking the NKG2D receptor significantly reduced this enhancement. NKG2D receptor expression was increased by docetaxel treatment in circulating and splenic NK cells from mice xenografted with tumor cells, an increase related to expansion of the CD11b+Ly6G+ cell population. Accordingly, NK cells derived from HER2+ BC patients after treatment with taxane-containing therapy expressed higher levels of NKG2D receptor than before treatment. Moreover, plasma obtained from these patients recapitulated the modulation of NKG2D on healthy donors' NK cells, improving their trastuzumab-mediated activity in vitro. This enhancement occurred mainly using plasma from patients with low NKG2D basal expression. Our results indicate that taxanes increase tumor susceptibility to ADCC by acting on tumor and NK cells, and suggest that taxanes concomitantly administered with trastuzumab could maximize the antibody effect, especially in patients with low basal immune effector cytotoxic activity.

  9. Bcl10 plays a divergent role in NK cell-mediated cytotoxicity and cytokine generation.

    PubMed

    Malarkannan, Subramaniam; Regunathan, Jeyarani; Chu, Haiyan; Kutlesa, Snjezana; Chen, Yuhong; Zeng, Hu; Wen, Renren; Wang, Demin

    2007-09-15

    Activating receptors such as NKG2D and Ly49D mediate a multitude of effector functions including cytotoxicity and cytokine generation in NK cells. However, specific signaling events that are responsible for the divergence of distinct effector functions have yet to be determined. In this study, we show that lack of caspase recruitment domain-containing protein Bcl10 significantly affected receptor-mediated cytokine and chemokine generation, but not cytotoxicity against tumor cells representing "missing-self" or "induced-self." Lack of Bcl10 completely abrogated the generation of GM-CSF and chemokines and it significantly reduced the generation of IFN-gamma (>75%) in NK cells. Commitment, development, and terminal maturation of NK cells were largely unaffected in the absence of Bcl10. Although IL-2-activated NK cells could mediate cytotoxicity to the full extent, the ability of the freshly isolated NK cells to mediate cytotoxicity was somewhat reduced. Therefore, we conclude that the Carma1-Bcl10-Malt1 signaling axis is critical for cytokine and chemokine generation, although it is dispensable for cytotoxic granule release depending on the activation state of NK cells. These results indicate that Bcl10 represents an exclusive "molecular switch" that links the upstream receptor-mediated signaling to cytokine and chemokine generations.

  10. RB mutation and RAS overexpression induce resistance to NK cell-mediated cytotoxicity in glioma cells.

    PubMed

    Orozco-Morales, Mario; Sánchez-García, Francisco Javier; Golán-Cancela, Irene; Hernández-Pedro, Norma; Costoya, Jose A; de la Cruz, Verónica Pérez; Moreno-Jiménez, Sergio; Sotelo, Julio; Pineda, Benjamín

    2015-01-01

    Several theories aim to explain the malignant transformation of cells, including the mutation of tumor suppressors and proto-oncogenes. Deletion of Rb (a tumor suppressor), overexpression of mutated Ras (a proto-oncogene), or both, are sufficient for in vitro gliomagenesis, and these genetic traits are associated with their proliferative capacity. An emerging hallmark of cancer is the ability of tumor cells to evade the immune system. Whether specific mutations are related with this, remains to be analyzed. To address this issue, three transformed glioma cell lines were obtained (Rb(-/-), Ras(V12), and Rb(-/-)/Ras(V12)) by in vitro retroviral transformation of astrocytes, as previously reported. In addition, Ras(V12) and Rb(-/-)/Ras(V12) transformed cells were injected into SCID mice and after tumor growth two stable glioma cell lines were derived. All these cells were characterized in terms of Rb and Ras gene expression, morphology, proliferative capacity, expression of MHC I, Rae1δ, and Rae1αβγδε, mult1, H60a, H60b, H60c, as ligands for NK cell receptors, and their susceptibility to NK cell-mediated cytotoxicity. Our results show that transformation of astrocytes (Rb loss, Ras overexpression, or both) induced phenotypical and functional changes associated with resistance to NK cell-mediated cytotoxicity. Moreover, the transfer of cell lines of transformed astrocytes into SCID mice increased resistance to NK cell-mediated cytotoxicity, thus suggesting that specific changes in a tumor suppressor (Rb) and a proto-oncogene (Ras) are enough to confer resistance to NK cell-mediated cytotoxicity in glioma cells and therefore provide some insight into the ability of tumor cells to evade immune responses.

  11. CDK8-Mediated STAT1-S727 Phosphorylation Restrains NK Cell Cytotoxicity and Tumor Surveillance

    PubMed Central

    Putz, Eva Maria; Gotthardt, Dagmar; Hoermann, Gregor; Csiszar, Agnes; Wirth, Silvia; Berger, Angelika; Straka, Elisabeth; Rigler, Doris; Wallner, Barbara; Jamieson, Amanda M.; Pickl, Winfried F.; Zebedin-Brandl, Eva Maria; Müller, Mathias; Decker, Thomas; Sexl, Veronika

    2013-01-01

    Summary The transcription factor STAT1 is important in natural killer (NK) cells, which provide immediate defense against tumor and virally infected cells. We show that mutation of a single phosphorylation site (Stat1-S727A) enhances NK cell cytotoxicity against a range of tumor cells, accompanied by increased expression of perforin and granzyme B. Stat1-S727A mice display significantly delayed disease onset in NK cell-surveilled tumor models including melanoma, leukemia, and metastasizing breast cancer. Constitutive phosphorylation of S727 depends on cyclin-dependent kinase 8 (CDK8). Inhibition of CDK8-mediated STAT1-S727 phosphorylation may thus represent a therapeutic strategy for stimulating NK cell-mediated tumor surveillance. PMID:23933255

  12. Increased Tim-3 expression in peripheral NK cells predicts a poorer prognosis and Tim-3 blockade improves NK cell-mediated cytotoxicity in human lung adenocarcinoma.

    PubMed

    Xu, Liyun; Huang, Yanyan; Tan, Linlin; Yu, Wei; Chen, Dongdong; Lu, ChangChang; He, Jianying; Wu, Guoqing; Liu, Xiaoguang; Zhang, Yongkui

    2015-12-01

    T cell immunoglobulin- and mucin-domain-containing molecule-3 (Tim-3) has been shown to play an important role in mediating NK-cell function in human diseases. However, the relationship between Tim-3 expression in natural killer (NK) cells and human lung adenocarcinoma remains unclear. We therefore investigated the expression of Tim-3 in NK cells and explored the effect of Tim-3 blockade on NK cell-mediated activity in human lung adenocarcinoma. Upregulated expression of Tim-3 on CD3-CD56+ cells (P<0.05) and CD3-CD56(dim) cells (P<0.05) of patients with lung adenocarcinoma was detected by flow cytometry. Moreover, Tim-3 expression in CD3-CD56+ NK cells was higher in patients with lung adenocarcinoma with lymph node metastasis (LNM) (P<0.05) or with tumor stage T3-T4 (P<0.05). Tim-3 expression in CD56(dim) NK-cell subset was higher in patients with tumor size ≥3cm (P<0.05), or LNM (P<0.05) or with tumor stage T3-T4 (P<0.05). Further analysis showed that higher expressions of Tim-3 on both CD3-CD56+ NK cells and CD56(dim) NK-cell subset were independently correlated with shorter overall survival of patients with lung adenocarcinoma (log-rank test, P=0.0418, 0.0406, respectively). Importantly, blockade of Tim-3 signaling with anti-Tim-3 antibodies resulted in the increased cytotoxicity and IFN-γ production of peripheral NK cells from patients with lung adenocarcinoma. Our data indicate that Tim-3 expression in NK cells can function as a prognostic biomarker in human lung adenocarcinoma and support that Tim-3 could be a new target for an immunotherapeutic strategy.

  13. NK Cells in HIV Disease.

    PubMed

    Scully, Eileen; Alter, Galit

    2016-04-01

    Natural killer (NK) cells play a critical role in viral immunity. In the setting of HIV infection, epidemiologic and functional evidence support a role for NK cells in both protection from new infection and in viral control. Specifically, NK cells directly mediate immune pressure leading to virus evolution, and NK cell receptor genotypic profiles, clonal repertoires, and functional capacity have all been implicated in virus containment. In addition, indirect NK cell-mediated antibody-dependent cellular cytotoxicity has been linked to vaccine-induced protective immunity against HIV infection. With recent advances in our understanding of NK cell deficiency, development, memory-like responses, and editing of the adaptive immune system, the opportunities to direct and exploit NK cell antiviral immunity to target HIV have exponentially grown. In this review, we seek to highlight the intersections between discoveries in basic NK cell biology and the challenges of HIV chronic infection, vaccine development, and cure/eradication strategies.

  14. Sleep-deprivation reduces NK cell number and function mediated by β-adrenergic signalling.

    PubMed

    De Lorenzo, Beatriz H P; de Oliveira Marchioro, Laís; Greco, Carollina Ribeiro; Suchecki, Deborah

    2015-07-01

    Reduction of sleep time triggers a stress response, leading to augmented levels of glucocorticoids and adrenaline. These hormones regulate components of the innate immune system such as natural killer (NK) and NKT cells. In the present study, we sought to investigate whether and how stress hormones could alter the population and function of NK and NKT cells of mice submitted to different lengths of paradoxical sleep deprivation (PSD, from 24 to 72 h). Results showed that 72h of PSD decreased not only NK and NKT cell counts, but also their cytotoxic activity against B16F10 melanoma cells in vitro. Propranolol treatment during PSD reversed these effects, indicating a major inhibitory role of beta-adrenergic receptors (β-AR) on NK cells function. Moreover, both corticosterone plasma levels and expression of beta 2-adrenergic receptors (β2-AR) in NK cells increased by 48 h of PSD. In vitro incubation of NK cells with dexamethasone augmented the level of β2-AR in the cell surface, suggesting that glucocorticoids could induce β2-AR expression. In summary, we propose that reduction of NK and NKT cell number and cytotoxic activity appears to be mediated by glucocorticoids-induced increased expression of β2-AR in these cells.

  15. NK Cells and Cancer Immunoediting.

    PubMed

    Guillerey, Camille; Smyth, Mark J

    2016-01-01

    Natural killer (NK) cells are innate lymphoid cells (ILC) known for their ability to recognize and rapidly eliminate infected or transformed cells. Consequently, NK cells are fundamental for host protection against virus infections and malignancies. Even though the critical role of NK cells in cancer immunosurveillance was suspected years ago, the underlying mechanisms took time to be unraveled. Today, it is clear that anti-tumor functions of NK cells are tightly regulated and expand far beyond the simple killing of malignant cells. In spite of tremendous steps made in understanding the NK cell biology, further work is warranted to fully exploit the anticancer potential of these cells. Indeed, tumor-mediated immune suppression hampers NK cell activity, thus complicating their stimulation for therapeutic purposes. Herein, we review the current knowledge of NK cell functions in anti-tumor immunity . We discuss NK cell activity in the cancer immunoediting process with particular emphasis on the elimination and escape phases.

  16. Curcumin reverses breast tumor exosomes mediated immune suppression of NK cell tumor cytotoxicity

    PubMed Central

    Zhang, Huang-Ge; Kim, Helen; Liu, Cunren; Yu, Shaohua; Wang, Jianhua; Grizzle, William E.; Kimberly, Robert P.; Barnes, Stephen

    2007-01-01

    An important characteristic of tumors is that they at some point in their development overcome the surveillance of the immune system. Tumors secrete exosomes, multivesicular bodies containing a distinct set of proteins that can fuse with cells of the circulating immune system. Purified exosomes from TS/A breast cancer cells, but not non-exosomal fractions, inhibit (at concentrations of nanograms per ml protein) IL-2-induced natural killer (NK) cell cytotoxicity. The dietary polyphenol, curcumin (diferuloylmethane), partially reverses tumor exosome-mediated inhibition of natural killer cell activation, which is mediated through the impairment of the ubiquitin-proteasome system. Exposure of mouse breast tumor cells to curcumin causes a dose-dependent increase in ubiquitinated exosomal proteins compared to those in untreated TS/A breast tumor cells. Furthermore, exosomes isolated from tumor cells pretreated with curcumin have a much attenuated inhibition of IL-2 stimulated NK cell activation. Jak3-mediated activation of Stat5 is required for tumor cytotoxicity of IL-2 stimulated NK cells. TS/A tumor exosomes strongly inhibit activation of Stat5, whereas the tumor exosomes isolated from curcumin-pretreated tumor cells have a lowered potency for inhibition of IL-2 stimulated NK cell cytotoxicity. These data suggest that partial reversal of tumor exosome-mediated inhibition of NK cell tumor cytotoxicity may account for the anti-cancer properties curcumin. PMID:17555831

  17. Phenotypically distinct helper NK cells are required for gp96-mediated anti-tumor immunity

    PubMed Central

    Sedlacek, Abigail L.; Kinner-Bibeau, Lauren B.; Binder, Robert J.

    2016-01-01

    A number of Heat Shock Proteins (HSPs), in the extracellular environment, are immunogenic. Following cross-presentation of HSP-chaperoned peptides by CD91+ antigen presenting cells (APCs), T cells are primed with specificity for the derivative antigen-bearing cell. Accordingly, tumor-derived HSPs are in clinical trials for cancer immunotherapy. We investigate the role of NK cells in gp96-mediated anti-tumor immune responses given their propensity to lyse tumor cells. We show that gp96-mediated rejection of tumors requires a unique and necessary helper role in NK cells. This helper role occurs during the effector phase of the anti-tumor immune response and is required for T cell and APC function. Gp96 activates NK cells indirectly via APCs to a phenotype distinct from NK cells activated by other mechanisms such as IL-2. While NK cells have both lytic and cytokine producing properties, we show that gp96 selectively activates cytokine production in NK cells, which is important in the HSP anti-tumor immune response, and leaves their cytotoxic capacity unchanged. PMID:27431727

  18. WASH has a critical role in NK cell cytotoxicity through Lck-mediated phosphorylation

    PubMed Central

    Huang, L; Zhu, P; Xia, P; Fan, Z

    2016-01-01

    Natural killer (NK) cells are important effector cells of the innate immune system to kill certain virus-infected and transformed cells. Wiskott–Aldrich Syndrome protein (WASP) and SCAR homolog (WASH) has been identified as a member of WASP family proteins implicated in regulating the cytoskeletal reorganization, yet little is known about its function in lymphocytes. Here we demonstrate that WASH is crucial for NK cell cytotoxicity. WASH was found to colocalize with lytic granules upon NK cell activation. Knockdown of WASH expression substantially inhibited polarization and release of lytic granules to the immune synapse, resulting in the impairment of NK cell cytotoxicity. More importantly, our data also define a previously unappreciated mechanism for WASH function, in which Src family kinase Lck can interact with WASH and induce WASH phosphorylation. Mutation of tyrosine residue Y141, identified here as the major site of WASH phosphorylation, partially blocked WASH tyrosine phosphorylation and NK cell cytotoxicity. Taken together, these observations suggest that WASH has a pivotal role for regulation of NK cell cytotoxicity through Lck-mediated Y141 tyrosine phosphorylation. PMID:27441653

  19. Human NK cell development requires CD56-mediated motility and formation of the developmental synapse

    PubMed Central

    Mace, Emily M.; Gunesch, Justin T.; Dixon, Amera; Orange, Jordan S.

    2016-01-01

    While distinct stages of natural killer (NK) cell development have been defined, the molecular interactions that shape human NK cell maturation are poorly understood. Here we define intercellular interactions between developing NK cells and stromal cells which, through contact-dependent mechanisms, promote the generation of mature, functional human NK cells from CD34+ precursors. We show that developing NK cells undergo unique, developmental stage-specific sustained and transient interactions with developmentally supportive stromal cells, and that the relative motility of NK cells increases as they move through development in vitro and ex vivo. These interactions include the formation of a synapse between developing NK cells and stromal cells, which we term the developmental synapse. Finally, we identify a role for CD56 in developmental synapse structure, NK cell motility and NK cell development. Thus, we define the developmental synapse leading to human NK cell functional maturation. PMID:27435370

  20. Antibody Fc engineering improves frequency and promotes kinetic boosting of serial killing mediated by NK cells.

    PubMed

    Romain, Gabrielle; Senyukov, Vladimir; Rey-Villamizar, Nicolas; Merouane, Amine; Kelton, William; Liadi, Ivan; Mahendra, Ankit; Charab, Wissam; Georgiou, George; Roysam, Badrinath; Lee, Dean A; Varadarajan, Navin

    2014-11-20

    The efficacy of most therapeutic monoclonal antibodies (mAbs) targeting tumor antigens results primarily from their ability to elicit potent cytotoxicity through effector-mediated functions. We have engineered the fragment crystallizable (Fc) region of the immunoglobulin G (IgG) mAb, HuM195, targeting the leukemic antigen CD33, by introducing the triple mutation Ser293Asp/Ala330Leu/Ile332Glu (DLE), and developed Time-lapse Imaging Microscopy in Nanowell Grids to analyze antibody-dependent cell-mediated cytotoxicity kinetics of thousands of individual natural killer (NK) cells and mAb-coated target cells. We demonstrate that the DLE-HuM195 antibody increases both the quality and the quantity of NK cell-mediated antibody-dependent cytotoxicity by endowing more NK cells to participate in cytotoxicity via accrued CD16-mediated signaling and by increasing serial killing of target cells. NK cells encountering targets coated with DLE-HuM195 induce rapid target cell apoptosis by promoting simultaneous conjugates to multiple target cells and induce apoptosis in twice the number of target cells within the same period as the wild-type mAb. Enhanced target killing was also associated with increased frequency of NK cells undergoing apoptosis, but this effect was donor-dependent. Antibody-based therapies targeting tumor antigens will benefit from a better understanding of cell-mediated tumor elimination, and our work opens further opportunities for the therapeutic targeting of CD33 in the treatment of acute myeloid leukemia.

  1. Smad3 promotes cancer progression by inhibiting E4BP4-mediated NK cell development

    PubMed Central

    Tang, Patrick Ming-Kuen; Zhou, Shuang; Meng, Xiao-Ming; Wang, Qing-Ming; Li, Chun-Jie; Lian, Guang-Yu; Huang, Xiao-Ru; Tang, Yong-Jiang; Guan, Xin-Yuan; Yan, Bryan Ping-Yen; To, Ka-Fai; Lan, Hui-Yao

    2017-01-01

    TGF-β is known to influence tumour progression. Here we report an additional role of Smad3 in the tumour microenvironment regulating cancer progression. Deletion or inhibition of Smad3 in the tumour microenvironment suppresses tumour growth, invasion and metastasis in two syngeneic mouse tumour models. Smad3−/− bone marrow gives rise to an expanded NK cell population with enhanced tumour-suppressive activities in vivo, and promotes differentiation of NK cells ex vivo. We identify E4BP4/NFIL3 as a direct Smad3 target gene critical for NK cell differentiation. Smad3 suppresses transcription of IFN-γ via E4BP4 in a T-bet independent manner. Therefore disruption of Smad3 enhances both the E4BP4-mediated NK cell differentiation and anti-cancer effector functions in vivo and in vitro. Furthermore, systemic treatment with a Smad3 inhibitor SIS3 effectively suppresses cancer progression. In summary, suppression of NK cell-mediated immunosurveillance via the Smad3-E4BP4 axis contributes to cancer progression. We propose targeting Smad3-dependent tumour microenvironment may represent an effective anti-cancer strategy. PMID:28262747

  2. Smad3 promotes cancer progression by inhibiting E4BP4-mediated NK cell development.

    PubMed

    Tang, Patrick Ming-Kuen; Zhou, Shuang; Meng, Xiao-Ming; Wang, Qing-Ming; Li, Chun-Jie; Lian, Guang-Yu; Huang, Xiao-Ru; Tang, Yong-Jiang; Guan, Xin-Yuan; Yan, Bryan Ping-Yen; To, Ka-Fai; Lan, Hui-Yao

    2017-03-06

    TGF-β is known to influence tumour progression. Here we report an additional role of Smad3 in the tumour microenvironment regulating cancer progression. Deletion or inhibition of Smad3 in the tumour microenvironment suppresses tumour growth, invasion and metastasis in two syngeneic mouse tumour models. Smad3(-/-) bone marrow gives rise to an expanded NK cell population with enhanced tumour-suppressive activities in vivo, and promotes differentiation of NK cells ex vivo. We identify E4BP4/NFIL3 as a direct Smad3 target gene critical for NK cell differentiation. Smad3 suppresses transcription of IFN-γ via E4BP4 in a T-bet independent manner. Therefore disruption of Smad3 enhances both the E4BP4-mediated NK cell differentiation and anti-cancer effector functions in vivo and in vitro. Furthermore, systemic treatment with a Smad3 inhibitor SIS3 effectively suppresses cancer progression. In summary, suppression of NK cell-mediated immunosurveillance via the Smad3-E4BP4 axis contributes to cancer progression. We propose targeting Smad3-dependent tumour microenvironment may represent an effective anti-cancer strategy.

  3. NLRP3 suppresses NK cell-mediated responses to carcinogen-induced tumors and metastases.

    PubMed

    Chow, Melvyn T; Sceneay, Jaclyn; Paget, Christophe; Wong, Christina S F; Duret, Helene; Tschopp, Jürg; Möller, Andreas; Smyth, Mark J

    2012-11-15

    The NLRP3 inflammasome acts as a danger signal sensor that triggers and coordinates the inflammatory response upon infectious insults or tissue injury and damage. However, the role of the NLRP3 inflammasome in natural killer (NK) cell-mediated control of tumor immunity is poorly understood. Here, we show in a model of chemical-induced carcinogenesis and a series of experimental and spontaneous metastases models that mice lacking NLRP3 display significantly reduced tumor burden than control wild-type (WT) mice. The suppression of spontaneous and experimental tumor metastases and methylcholanthrene (MCA)-induced sarcomas in mice deficient for NLRP3 was NK cell and IFN-γ-dependent. Focusing on the amenable B16F10 experimental lung metastases model, we determined that expression of NLRP3 in bone marrow-derived cells was necessary for optimal tumor metastasis. Tumor-driven expansion of CD11b(+)Gr-1(intermediate) (Gr-1(int)) myeloid cells within the lung tumor microenvironment of NLRP3(-/-) mice was coincident with increased lung infiltrating activated NK cells and an enhanced antimetastatic response. The CD11b(+)Gr-1(int) myeloid cells displayed a unique cell surface phenotype and were characterized by their elevated production of CCL5 and CXCL9 chemokines. Adoptive transfer of this population into WT mice enhanced NK cell numbers in, and suppression of, B16F10 lung metastases. Together, these data suggested that NLRP3 is an important suppressor of NK cell-mediated control of carcinogenesis and metastases and identify CD11b(+)Gr-1(int) myeloid cells that promote NK cell antimetastatic function.

  4. Heparan sulfate mimetic PG545-mediated antilymphoma effects require TLR9-dependent NK cell activation

    PubMed Central

    Brennan, Todd V.; Lin, Liwen; Brandstadter, Joshua D.; Rendell, Victoria R.; Dredge, Keith; Huang, Xiaopei; Yang, Yiping

    2015-01-01

    Heparan sulfate (HS) is an essential component of the extracellular matrix (ECM), which serves as a barrier to tumor invasion and metastasis. Heparanase promotes tumor growth by cleaving HS chains of proteoglycan and releasing HS-bound angiogenic growth factors and facilitates tumor invasion and metastasis by degrading the ECM. HS mimetics, such as PG545, have been developed as antitumor agents and are designed to suppress angiogenesis and metastasis by inhibiting heparanase and competing for the HS-binding domain of angiogenic growth factors. However, how PG545 exerts its antitumor effect remains incompletely defined. Here, using murine models of lymphoma, we determined that the antitumor effects of PG545 are critically dependent on NK cell activation and that NK cell activation by PG545 requires TLR9. We demonstrate that PG545 does not activate TLR9 directly but instead enhances TLR9 activation through the elevation of the TLR9 ligand CpG in DCs. Specifically, PG545 treatment resulted in CpG accumulation in the lysosomal compartment of DCs, leading to enhanced production of IL-12, which is essential for PG545-mediated NK cell activation. Overall, these results reveal that PG545 activates NK cells and that this activation is critical for the antitumor effect of PG545. Moreover, our findings may have important implications for improving NK cell–based antitumor therapies. PMID:26649979

  5. Acute Virus Control Mediated by Licensed NK Cells Sets Primary CD8+ T Cell Dependence on CD27 Costimulation.

    PubMed

    Teoh, Jeffrey J; Gamache, Awndre E; Gillespie, Alyssa L; Stadnisky, Michael D; Yagita, Hideo; Bullock, Timothy N J; Brown, Michael G

    2016-12-01

    NK cells represent a critical first-line of immune defense against a bevy of viral pathogens, and infection can provoke them to mediate supportive and suppressive effects on virus-specific adaptive immunity. In mice expressing MHC class I D(k) (D(k)), a major murine CMV (MCMV) resistance factor and self-ligand of the inhibitory Ly49G2 (G2) receptor, licensed G2(+) NK cells provide essential host resistance against MCMV infection. Additionally G2(+) NK cell responses to MCMV increase the rate and extent of dendritic cell (DC) recovery, as well as early priming of CD8(+) T cell effectors in response to MCMV. However, relatively little is known about the NK cell effect on costimulatory ligand patterns displayed by DCs or on ensuing effector and memory T cell responses. In this study, we found that CD27-dependent CD8(+) T cell priming and differentiation are shaped by the efficiency of NK responses to virus infection. Surprisingly, differences in specific NK responses to MCMV in D(k)-disparate mice failed to distinguish early DC costimulatory patterns. Nonetheless, although CD27 deficiency did not impede licensed NK-mediated resistance, CD70 and CD27 were required to efficiently prime and regulate effector CD8(+) T cell differentiation in response to MCMV, which eventually resulted in biased memory T cell precursor formation in D(k) mice. In contrast, CD8(+) T cells accrued more slowly in non-D(k) mice and eventually differentiated into terminal effector cells regardless of CD27 stimulation. Disparity in this requirement for CD27 signaling indicates that specific virus control mediated by NK cells can shape DC costimulatory signals needed to prime CD8(+) T cells and eventual T cell fate decisions.

  6. Epirubicin pretreatment enhances NK cell-mediated cytotoxicity against breast cancer cells in vitro.

    PubMed

    Feng, Hui; Dong, Ying; Wu, Jing; Qiao, Yuan; Zhu, Ge; Jin, Haofan; Cui, Jiuwei; Li, Wei; Liu, Yong-Jun; Chen, Jingtao; Song, Yanqiu

    2016-01-01

    Anthracycline-based chemotherapy is a conventional treatment for breast cancer. However, it can negatively affect host immune function and thereby impair patients' quality of life. Boosting the host immune system and reducing the adverse effect of chemotherapy are important for effective cancer treatment. Natural killer (NK) cells stimulate immune responses against cancer; autologous immune enhancement therapy with NK cells prolongs patient survival without significant adverse effects. This study investigated the effects of combined treatment with the anthracycline agent epirubicin (EPI) and NK cells on human breast cancer cells. NK cells were obtained by autologous adoptive cell transfer from breast cancer patients and amplified for 14 days in vitro. The cytotoxicity of NK cells against breast cancer cells was higher following EPI (5.0 μg/ml) pretreatment than without EPI pretreatment or application of EPI alone. The expression of NKG2D ligands [unique long 16-binding protein (ULBP) 1, ULBP2, and major histocompatibility complex class I-related chain A] in breast cancer cells was upregulated by pretreatment with EPI, which also increased the secretion of interferon-γ and tumor necrosis factor-α and expression of perforin and granzyme B in NK cells. These results indicate that EPI-NK cell treatment has synergistic cytotoxic effects against breast cancer cells, and suggest that anthracycline-based chemotherapy and NK cell-based immunotherapy can be combined for more effective breast cancer treatment.

  7. Regulation of autoimmune diabetes by complete Freund's adjuvant is mediated by NK cells.

    PubMed

    Lee, I-Fang; Qin, Huilian; Trudeau, Jacqueline; Dutz, Jan; Tan, Rusung

    2004-01-15

    Autoimmune (type 1) diabetes results from a loss of beta cells that is mediated by self-reactive T cells. Previous studies have shown that a single injection of CFA prevents diabetes in nonobese diabetic (NOD) mice, but the mechanism(s) of protection remain unknown. We show here that NOD mice immunized with CFA have a markedly reduced incidence of diabetes and that this reduced incidence is associated with a decrease in the number of beta cell-specific, autoreactive CTL. In addition, the adoptive transfer of diabetes into syngeneic NOD/SCID recipients was prevented by CFA immunization, and the protective effects of CFA were lost when cells expressing the NK cell marker, asialo GM1, were removed from both donor cells and recipient mice. Returning a population of CD3-DX5+ cells to the adoptive transfer restored the protective effects of CFA. Therefore, NK cells mediate the protective effects of CFA possibly through the down-regulation of autoreactive CTL and stimulation of NK cells represents a novel approach to the prevention of autoimmune diabetes.

  8. Redirecting NK cells mediated tumor cell lysis by a new recombinant bifunctional protein

    PubMed Central

    Germain, Claire; Campigna, Emmanuelle; Salhi, Imed; Morisseau, Sébastien; Navarro-Teulon, Isabelle; Mach, Jean-Pierre; Pèlegrin, André; Robert, Bruno

    2008-01-01

    Natural killer (NK) cells are at the crossroad between innate and adaptive immunity and play a major role in cancer immunosurveillance. NK cell stimulation depends on a balance between inhibitory and activating receptors, such as the stimulatory lectinlike receptor NKG2D. To redirect NK cells against tumor cells we designed bifunctional proteins able to specifically bind tumor cells and to induce their lysis by NK cells, after NKG2D engagement. To this aim, we used the “knob into hole” heterodimerization strategy, in which “knob” and “hole” variants were generated by directed mutagenesis within the CH3 domain of human IgG1 Fc fragments fused to an anti-CEA or anti-HER2 scFv or to the H60 murine ligand of NKG2D, respectively. We demonstrated the capacity of the bifunctional proteins produced to specifically coat tumor cells surface with H60 ligand. Most importantly, we demonstrated that these bifunctional proteins were able to induce an NKG2D-dependent and antibody-specific tumor cell lysis by murine NK cells. Overall, the results show the possibility to redirect NK cytotoxicity to tumor cells by a new format of recombinant bispecific antibody, opening the way of potential NK cell-based cancer immunotherapies by specific activation of the NKG2D receptor at the tumor site. PMID:18790793

  9. Enhancement of NK cell-mediated lysis of non-small lung cancer cells by nPKC activator, ingenol 3,20 dibenzoate.

    PubMed

    Gong, Chenyuan; Yao, Chao; Xu, Zihang; Ni, Zhongya; Zhu, Xiaowen; Wang, Lixin; Yan, Xuewei; Zhou, Wuxiong; Zhu, Shiguo

    2017-03-01

    The IFN-γ production is crucial for NK cell-mediated lysis of cancer cells. Thus increasing the IFN-γ production by NK cells may be an ideal strategy to improve their tumoricidal effect. Since the focus on new drug development has shifted towards natural products, limited information is out there about natural products that enhance the IFN-γ production by NK cells. In this study, through a high-throughput screening, we have identified a natural product ingenol 3,20 dibenzoate (IDB), an activator of tumor suppressor protein kinase C (PKC) isozymes, could increase the IFN-γ production and degranulation by NK cells, especially when NK cells were stimulated by non-small lung cancer (NSCLC) cells. IDB also significantly enhanced the NK cell-mediated lysis of NSCLC cells. Furthermore, PKC inhibitor, sotrastaurin abrogated IDB-induced IFN-γ production, degranulation and cytotoxicity, but did not affect IFN-γ production by NK cells without IDB treatment and NSCLC cell stimulation. The IFN-γ neutralization reversed the IDB-induced enhancement of NK cell mediated killing. In conclusion, our study indicated that IDB enhanced NK cell-mediated lysis of NSCLC cells is dependent on specific PKC mediated IFN-γ production and degranulation. Thus, IDB may have a promising application in clinic for NK cell-based cancer immunotherapy.

  10. HIV-specific antibody immunity mediated through NK cells and monocytes.

    PubMed

    Kramski, Marit; Parsons, Matthew S; Stratov, Ivan; Kent, Stephen J

    2013-07-01

    The partial success of the RV144 trial re-energized the field of HIV vaccine research, which had stalled after vaccines based on neutralizing antibody and cytotoxic T cells had failed to induce protection. A large post-vaccine research effort has focused attention on the role of non-neutralizing antibodies in the protection afforded by the RV144 vaccine. These binding antibodies can initiate immune responses such as antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP) and combine elements of the adaptive and innate immune system in the form of antibodies and effector cells (including NK cells, monocytes and granulocytes). A complex interplay exists between the variable portion of the binding antibody and its HIV antigen target on one hand and the constant region of the antibody and the Fcγ-receptor of the effector cell on the other hand. Technical advances have revolutionized the abilities of scientist to detect the targets of non-neutralizing antibodies, including both envelope and non-envelope epitopes, and their role in forcing escape. Our understanding of the antibody characteristics (including IgG subclasses and Fc glycan profile) is providing valuable insights into their optimal structure and function. We expand on critical research on ADCC effector cells, particularly education of NK cells. We introduce the concept of HIV antibodydependent trogocytosis by monocytes as a potentially important aspect of HIV immunity. In summary, this review highlights recent advances in HIV-specific antibody immunity mediated through NK cells and monocytes.

  11. Impaired NK-mediated regulation of T-cell activity in multiple sclerosis is reconstituted by IL-2 receptor modulation.

    PubMed

    Gross, Catharina C; Schulte-Mecklenbeck, Andreas; Rünzi, Anna; Kuhlmann, Tanja; Posevitz-Fejfár, Anita; Schwab, Nicholas; Schneider-Hohendorf, Tilman; Herich, Sebastian; Held, Kathrin; Konjević, Matea; Hartwig, Marvin; Dornmair, Klaus; Hohlfeld, Reinhard; Ziemssen, Tjalf; Klotz, Luisa; Meuth, Sven G; Wiendl, Heinz

    2016-05-24

    Multiple sclerosis (MS) is a chronic inflammatory autoimmune disease of the central nervous system (CNS) resulting from a breakdown in peripheral immune tolerance. Although a beneficial role of natural killer (NK)-cell immune-regulatory function has been proposed, it still needs to be elucidated whether NK cells are functionally impaired as part of the disease. We observed NK cells in active MS lesions in close proximity to T cells. In accordance with a higher migratory capacity across the blood-brain barrier, CD56(bright) NK cells represent the major intrathecal NK-cell subset in both MS patients and healthy individuals. Investigating the peripheral blood and cerebrospinal fluid of MS patients treated with natalizumab revealed that transmigration of this subset depends on the α4β1 integrin very late antigen (VLA)-4. Although no MS-related changes in the migratory capacity of NK cells were observed, NK cells derived from patients with MS exhibit a reduced cytolytic activity in response to antigen-activated CD4(+) T cells. Defective NK-mediated immune regulation in MS is mainly attributable to a CD4(+) T-cell evasion caused by an impaired DNAX accessory molecule (DNAM)-1/CD155 interaction. Both the expression of the activating NK-cell receptor DNAM-1, a genetic alteration consistently found in MS-association studies, and up-regulation of the receptor's ligand CD155 on CD4(+) T cells are reduced in MS. Therapeutic immune modulation of IL-2 receptor restores impaired immune regulation in MS by increasing the proportion of CD155-expressing CD4(+) T cells and the cytolytic activity of NK cells.

  12. HLA-A11-mediated protection from NK cell-mediated lysis: role of HLA-A11-presented peptides.

    PubMed

    Gavioli, R; Zhang, Q J; Masucci, M G

    1996-08-01

    The capacity of MHC class I to protect target cells from NK is well established, but the mechanism by which these molecules influence NK recognition and the physical properties associated with this function remain poorly defined. We have examined this issue using as a model the HLA-A11 allele. HLA-A11 expression correlated with reduced susceptibility to NK and interferon-activated cytotoxicity in transfected sublines of the A11-defective Burkitt's lymphoma WW2-BL and the HLA class I A,B-null C1R cell line. Protection was also achieved by transfection of HLA-A11 in the peptide processing mutant T2 cells line (T2/A11), despite a very low expression of the transfected product at the cell surface. Induction of surface HLA-A11 by culture of T2/A11 cells at 26 degrees C or in the presence of beta 2m did not affect lysis, whereas NK sensitivity was restored by culture in the presence of HLA-All-binding synthetic peptides derived from viral or cellular proteins. Acid treatment rendered T2/A11 and C1R/A11 cells sensitive to lysis, but protection was restored after preincubation with peptide preparations derived from surface stripping of T2/A11 cells. Similar peptide preparations from T2 cells had no effect. The results suggest that NK protection is mediated by HLA-A11 molecules carrying a particular set of peptides that are translocated to the site of MHC class I assembly in the ER in a TAP-independent fashion.

  13. The Smac Mimetic BV6 Improves NK Cell-Mediated Killing of Rhabdomyosarcoma Cells by Simultaneously Targeting Tumor and Effector Cells.

    PubMed

    Fischer, Kyra; Tognarelli, Sara; Roesler, Stefanie; Boedicker, Cathinka; Schubert, Ralf; Steinle, Alexander; Klingebiel, Thomas; Bader, Peter; Fulda, Simone; Ullrich, Evelyn

    2017-01-01

    Rhabdomyosarcoma (RMS), the most common cancer of connective tissues in pediatrics, is often resistant to conventional therapies. One underlying mechanism of this resistance is the overexpression of Inhibitor of Apoptosis (IAP) proteins, leading to a dysfunctional cell death program within tumor cells. Smac mimetics (SM) are small molecules that can reactivate the cell death program by antagonizing IAP proteins and thereby compensating their overexpression. Here, we report that SM sensitize two RMS cell lines (RD and RH30) toward natural killer (NK) cell-mediated killing on the one hand, and increase the cytotoxic potential of NK cells on the other. The SM-induced sensitization of RH30 cells toward NK cell-mediated killing is significantly reduced through blocking tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) on NK cells prior to coculture. In addition, the presence of zVAD.fmk, a pancaspase inhibitor, rescues tumor cells from the increase in killing, indicating an apoptosis-dependent cell death. On the NK cell side, the presence of SM in addition to IL-2 during the ex vivo expansion leads to an increase in their cytotoxic activity against RH30 cells. This effect is mainly TNFα-dependent and partially mediated by NK cell activation, which is associated with transcriptional upregulation of NF-κB target genes such as IκBα and RelB. Taken together, our findings implicate that SM represent a novel double-hit strategy, sensitizing tumor and activating NK cells with one single drug.

  14. Viral infection transiently reverses activation receptor-mediated NK cell hyporesponsiveness in an MHC class I-independent mechanism.

    PubMed

    Mazumdar, Budhaditya; Bolanos, Fred D; Tripathy, Sandeep K

    2013-05-01

    Continuous engagement of the Ly49H activating receptor with its ligand (m157) in a transgenic mouse expressing m157 (m157-Tg) results in hyporesponsiveness of Ly49H(+) NK cells. The same interaction, during murine cytomegalovirus (MCMV) infection, leads to activation of Ly49H(+) NK cells. MCMV infection results in decreased MHC class I (MHC-I) expression on the infected cell as well as inflammatory responses, both of which do not take place in the uninfected m157-Tg mouse, potentially allowing for activation of NK cells in the context of MCMV infection. In this study, we demonstrated that viral infection transiently reverses activation receptor-mediated NK cell hyporesponsiveness in an MHC-I-independent mechanism. Furthermore, Ly49H(+) NK cells in an MHC-I-deficient environment remained hyporesponsive in the context of m157 expression, even when mature WT splenocytes were transferred into m157-Tg mice in an MHC-I-deficient environment. However, the administration of cytokines TNF-α, IL-12, and IFN-β resulted in a partial recovery from activation receptor-induced hyporesponsiveness. Thus, the release of the aforementioned cytokines during MCMV infection and not the downregulation of MHC-I expression appears to be responsible for partial resolution of Ly49H receptor-induced NK cell hyporesponsiveness.

  15. Tissue resident NK cells mediate ischemic kidney injury and are not depleted by anti-Asialo GM1 antibody

    PubMed Central

    Victorino, Francisco; Sojka, Dorothy K.; Brodsky, Kelley S.; McNamee, Eoin N.; Masterson, Joanne C.; Homann, Dirk; Yokoyama, Wayne M.; Eltzschig, Holger K.; Clambey, Eric T.

    2015-01-01

    NK cells are innate lymphoid cells important for immune surveillance, identifying and responding to stress, infection, and/or transformation. While conventional NK (cNK) cells circulate systemically, many NK cells reside in tissues where they appear to be poised to locally regulate tissue function. Here we tested the contribution of tissue-resident NK (trNK) cells to tissue homeostasis by studying ischemic injury in the mouse kidney. Parabiosis experiments demonstrate that the kidney contains a significant fraction of trNK cells under homeostatic conditions. Kidney trNK cells developed independent of NFIL3 and Tbet, and expressed a distinct cell surface phenotype as compared to cNK cells. Among these, trNK cells had reduced asialo-GM1 (AsGM1) expression relative to cNK cells, a phenotype observed in trNK cells across multiple organs and mouse strains. Strikingly, anti-AsGM1 antibody treatment, commonly used as NK cell-depleting regimen, resulted in a robust and selective depletion of cNKs, leaving trNKs largely intact. Using this differential depletion, we tested the relative contribution of cNK and trNK cells in ischemic kidney injury. Whereas anti-NK1.1 antibody effectively depleted both trNK and cNK cells and protected against ischemic-reperfusion injury, anti-AsGM1 antibody preferentially depleted cNK cells and failed to protect against injury. These data demonstrate unanticipated specificity of anti-AsGM1 antibody depletion on NK cell subsets and reveal a new approach to study the contributions of cNK and trNK cells in vivo. In total, these data demonstrate that trNK cells play a key role in modulating local responses to ischemic tissue injury in the kidney and potentially other organs. PMID:26453755

  16. Overexpression of LLT1 (OCIL, CLEC2D) on prostate cancer cells inhibits NK cell-mediated killing through LLT1-NKRP1A (CD161) interaction.

    PubMed

    Mathew, Stephen O; Chaudhary, Pankaj; Powers, Sheila B; Vishwanatha, Jamboor K; Mathew, Porunelloor A

    2016-10-18

    Prostate cancer is the most common type of cancer diagnosed and the second leading cause of cancer-related death in American men. Natural Killer (NK) cells are the first line of defense against cancer and infections. NK cell function is regulated by a delicate balance between signals received through activating and inhibitory receptors. Previously, we identified Lectin-like transcript-1 (LLT1/OCIL/CLEC2D) as a counter-receptor for the NK cell inhibitory receptor NKRP1A (CD161). Interaction of LLT1 expressed on target cells with NKRP1A inhibits NK cell activation. In this study, we have found that LLT1 was overexpressed on prostate cancer cell lines (DU145, LNCaP, 22Rv1 and PC3) and in primary prostate cancer tissues both at the mRNA and protein level. We further showed that LLT1 is retained intracellularly in normal prostate cells with minimal cell surface expression. Blocking LLT1 interaction with NKRP1A by anti-LLT1 mAb on prostate cancer cells increased the NK-mediated cytotoxicity of prostate cancer cells. The results indicate that prostate cancer cells may evade immune attack by NK cells by expressing LLT1 to inhibit NK cell-mediated cytolytic activity through LLT1-NKRP1A interaction. Blocking LLT1-NKRP1A interaction will make prostate cancer cells susceptible to killing by NK cells and therefore may be a new therapeutic option for treatment of prostate cancer.

  17. HER2-specific immunoligands engaging NKp30 or NKp80 trigger NK-cell-mediated lysis of tumor cells and enhance antibody-dependent cell-mediated cytotoxicity.

    PubMed

    Peipp, Matthias; Derer, Stefanie; Lohse, Stefan; Staudinger, Matthias; Klausz, Katja; Valerius, Thomas; Gramatzki, Martin; Kellner, Christian

    2015-10-13

    NK cells detect tumors through activating surface receptors, which bind self-antigens that are frequently expressed upon malignant transformation. To increase the recognition of tumor cells, the extracellular domains of ligands of the activating NK cell receptors NKp30, NKp80 and DNAM-1 (i.e. B7-H6, AICL and PVR, respectively) were fused to a single-chain fragment variable (scFv) targeting the human epidermal growth factor receptor 2 (HER2), which is displayed by various solid tumors. The resulting immunoligands, designated B7-H6:HER2-scFv, AICL:HER2-scFv, and PVR:HER2-scFv, respectively, bound HER2 and the addressed NK cell receptor. However, whereas B7-H6:HER2-scFv and AICL:HER2-scFv triggered NK cells to kill HER2-positive breast cancer cells at nanomolar concentrations, PVR:HER2-scFv was not efficacious. Moreover, NK cell cytotoxicity was enhanced synergistically when B7-H6:HER2-scFv or AICL:HER2-scFv were applied in combination with another HER2-specific immunoligand engaging the stimulatory receptor NKG2D. In contrast, no improvements were achieved by combining B7-H6:HER2-scFv with AICL:HER2-scFv. Additionally, B7-H6:HER2-scFv and AICL:HER2-scFv enhanced antibody-dependent cell-mediated cytotoxicity (ADCC) by the therapeutic antibodies trastuzumab and cetuximab synergistically, with B7-H6:HER2-scFv exhibiting a higher efficacy. In summary, antibody-derived proteins engaging NKp30 or NKp80 may represent attractive biologics to further enhance anti-tumor NK cell responses and may provide an innovative approach to sensitize tumor cells for antibody-based immunotherapy.

  18. Sustained Immune Complex-Mediated Reduction in CD16 Expression after Vaccination Regulates NK Cell Function.

    PubMed

    Goodier, Martin R; Lusa, Chiara; Sherratt, Sam; Rodriguez-Galan, Ana; Behrens, Ron; Riley, Eleanor M

    2016-01-01

    Cross-linking of FcγRIII (CD16) by immune complexes induces antibody-dependent cellular cytotoxicity (ADCC) by natural killer (NK) cells, contributing to control of intracellular pathogens; this pathway can also be targeted for immunotherapy of cancerous or otherwise diseased cells. However, downregulation of CD16 expression on activated NK cells may limit or regulate this response. Here, we report sustained downregulation of CD16 expression on NK cells in vivo after intramuscular (but not intranasal) influenza vaccination. CD16 downregulation persisted for at least 12 weeks after vaccination and was associated with robust enhancement of influenza-specific plasma antibodies after intramuscular (but not intranasal) vaccination. This effect could be emulated in vitro by co-culture of NK cells with influenza antigen and immune serum and, consistent with the sustained effects after vaccination, only very limited recovery of CD16 expression was observed during long-term in vitro culture of immune complex-treated cells. CD16 downregulation was most marked among normally CD16(high) CD57(+) NK cells, irrespective of NKG2C expression, and was strongly positively associated with degranulation (surface CD107a expression). CD16 downregulation was partially reversed by inhibition of ADAM17 matrix metalloprotease, leading to a sustained increase in both CD107a and CD25 (IL-2Rα) expression. Both the degranulation and CD25 responses of CD57+ NK cells were uniquely dependent on trivalent influenza vaccine-specific IgG. These data support a role for CD16 in early activation of NK cells after vaccination and for CD16 downregulation as a means to modulate NK cell responses and maintain immune homeostasis of both antibody and T cell-dependent pathways.

  19. Sustained Immune Complex-Mediated Reduction in CD16 Expression after Vaccination Regulates NK Cell Function

    PubMed Central

    Goodier, Martin R.; Lusa, Chiara; Sherratt, Sam; Rodriguez-Galan, Ana; Behrens, Ron; Riley, Eleanor M.

    2016-01-01

    Cross-linking of FcγRIII (CD16) by immune complexes induces antibody-dependent cellular cytotoxicity (ADCC) by natural killer (NK) cells, contributing to control of intracellular pathogens; this pathway can also be targeted for immunotherapy of cancerous or otherwise diseased cells. However, downregulation of CD16 expression on activated NK cells may limit or regulate this response. Here, we report sustained downregulation of CD16 expression on NK cells in vivo after intramuscular (but not intranasal) influenza vaccination. CD16 downregulation persisted for at least 12 weeks after vaccination and was associated with robust enhancement of influenza-specific plasma antibodies after intramuscular (but not intranasal) vaccination. This effect could be emulated in vitro by co-culture of NK cells with influenza antigen and immune serum and, consistent with the sustained effects after vaccination, only very limited recovery of CD16 expression was observed during long-term in vitro culture of immune complex-treated cells. CD16 downregulation was most marked among normally CD16high CD57+ NK cells, irrespective of NKG2C expression, and was strongly positively associated with degranulation (surface CD107a expression). CD16 downregulation was partially reversed by inhibition of ADAM17 matrix metalloprotease, leading to a sustained increase in both CD107a and CD25 (IL-2Rα) expression. Both the degranulation and CD25 responses of CD57+ NK cells were uniquely dependent on trivalent influenza vaccine-specific IgG. These data support a role for CD16 in early activation of NK cells after vaccination and for CD16 downregulation as a means to modulate NK cell responses and maintain immune homeostasis of both antibody and T cell-dependent pathways. PMID:27725819

  20. Lenalidomide Induces Immunomodulation in Chronic Lymphocytic Leukemia and Enhances Antitumor Immune Responses Mediated by NK and CD4 T Cells

    PubMed Central

    Acebes-Huerta, Andrea; Huergo-Zapico, Leticia; Gonzalez-Rodriguez, Ana Pilar; Fernandez-Guizan, Azahara; Payer, Angel R.; Gonzalez, Segundo

    2014-01-01

    Lenalidomide is an immunomodulatory drug with therapeutic activity in chronic lymphocytic leukemia (CLL). However, it has pleiotropic effects, and the mechanism of action responsible for its therapeutic activity has not been well defined yet. Herein, we show that lenalidomide treatment does not have an effect on the proliferation of leukemia cells, but it increases the proliferation of B cells from healthy donors. Lenalidomide did not exert a direct effect on the apoptosis of leukemia cells obtained from CLL patients, although it indirectly induced their apoptosis through the activation of nonmalignant immune cells. Thus, lenalidomide markedly increased the proliferation of NK and CD4 T cells. The effect of lenalidomide on NK cells was secondary to the induction of IL-2 production by CD4 T cells. Accordingly, depletion of T cells or blockade of IL-2 activity completely abrogated the proliferation of NK cells. Additionally, lenalidomide enhanced NK and NKT-like cell-mediated natural cytotoxicity against leukemia cells from CLL patients. Lenalidomide also upregulated CD20 expression on leukemia cells and, accordingly, it had a synergistic effect with rituximab on promoting antibody-dependent cell-mediated cytotoxicity against primary leukemia cells. Overall, these observations provide a support for combining lenalidomide with rituximab as a treatment in CLL. PMID:25313353

  1. NK Cell-Mediated Regulation of Protective Memory Responses against Intracellular Ehrlichial Pathogens

    PubMed Central

    Habib, Samar; El Andaloussi, Abdeljabar; Hisham, Ahmed; Ismail, Nahed

    2016-01-01

    Ehrlichiae are gram-negative obligate intracellular bacteria that cause potentially fatal human monocytic ehrlichiosis. We previously showed that natural killer (NK) cells play a critical role in host defense against Ehrlichia during primary infection. However, the contribution of NK cells to the memory response against Ehrlichia remains elusive. Primary infection of C57BL/6 mice with Ehrlichia muris provides long-term protection against a second challenge with the highly virulent Ixodes ovatus Ehrlichia (IOE), which ordinarily causes fatal disease in naïve mice. Here, we show that the depletion of NK cells in E. muris-primed mice abrogates the protective memory response against IOE. Approximately, 80% of NK cell-depleted E. muris-primed mice succumbed to lethal IOE infection on days 8–10 after IOE infection, similar to naïve mice infected with the same dose of IOE. The lack of a recall response in NK cell-depleted mice correlated with an increased bacterial burden, extensive liver injury, decreased frequency of Ehrlichia-specific IFN-γ-producing memory CD4+ and CD8+ T-cells, and a low titer of Ehrlichia-specific antibodies. Intraperitoneal infection of mice with E. muris resulted in the production of IL-15, IL-12, and IFN-γ as well as an expansion of activated NKG2D+ NK cells. The adoptive transfer of purified E. muris-primed hepatic and splenic NK cells into Rag2-/-Il2rg-/- recipient mice provided protective immunity against challenge with E. muris. Together, these data suggest that E. muris-induced memory-like NK cells, which contribute to the protective, recall response against Ehrlichia. PMID:27092553

  2. NK cells are strongly activated by Lassa and Mopeia virus-infected human macrophages in vitro but do not mediate virus suppression.

    PubMed

    Russier, Marion; Reynard, Stéphanie; Tordo, Noël; Baize, Sylvain

    2012-07-01

    Lassa virus (LASV) and Mopeia virus (MOPV) are closely related Arenaviruses. LASV causes hemorrhagic fever, whereas MOPV is not pathogenic. Both viruses display tropism for APCs such as DCs and macrophages. During viral infections, NK cells are involved in the clearance of infected cells and promote optimal immune responses by interacting with APCs. We used an in vitro model of human NK and APC coculture to study the role of NK cells and to characterize their interactions with APCs during LASV and MOPV infections. As expected, NK cells alone were neither infected nor activated by LASV and MOPV, and infected DCs did not activate NK cells. By contrast, LASV- and MOPV-infected macrophages activated NK cells, as shown by the upregulation of CD69, NKp30, and NKp44, the downregulation of CXCR3, and an increase in NK-cell proliferation. NK cells acquired enhanced cytotoxicity, as illustrated by the increase in granzyme B (GrzB) expression and killing of K562 targets, but did not produce IFN-γ. Contact between NK cells and infected macrophages and type I IFNs were essential for activation; however, NK cells could not kill infected cells and control infection. Overall, these findings show that MOPV- as well as pathogenic LASV-infected macrophages mediate NK-cell activation.

  3. NK Cells Promote Th-17 Mediated Corneal Barrier Disruption in Dry Eye

    PubMed Central

    Zhang, Xiaobo; Volpe, Eugene A.; Gandhi, Niral B.; Schaumburg, Chris S.; Siemasko, Karyn F.; Pangelinan, Solherny B.; Kelly, Scott D.; Hayday, Adrian C.; Li, De-Quan; Stern, Michael E.; Niederkorn, Jerry Y.; Pflugfelder, Stephen C.; De Paiva, Cintia S.

    2012-01-01

    Background The conjunctiva contains a specialized population of lymphocytes that reside in the epithelium, named intraepithelial lymphocytes (IEL). Methodology/Principal Findings Here we characterized the IEL population prior to and after experimental desiccating stress (DS) for 5 or 10 days (DS5, DS10) and evaluated the effect of NK depletion on DS. The frequency of IELs in normal murine conjunctiva was CD3+CD103+ (∼22%), CD3+γδ+ (∼9.6%), CD3+NK+ (2%), CD3−NK+ (∼4.4%), CD3+CD8α (∼0.9%), and CD4 (∼0.6%). Systemic depletion of NK cells prior and during DS led to a decrease in the frequency of total and activated DCs, a decrease in T helper-17+ cells in the cervical lymph nodes and generation of less pathogenic CD4+T cells. B6.nude recipient mice of adoptively transferred CD4+T cells isolated from NK-depleted DS5 donor mice showed significantly less corneal barrier disruption, lower levels of IL-17A, CCL20 and MMP-3 in the cornea epithelia compared to recipients of control CD4+T cells. Conclusions/Significance Taken together, these results show that the NK IELs are involved in the acute immune response to desiccation-induced dry eye by activating DC, which in turn coordinate generation of the pathogenic Th-17 response. PMID:22590618

  4. The Smac Mimetic BV6 Improves NK Cell-Mediated Killing of Rhabdomyosarcoma Cells by Simultaneously Targeting Tumor and Effector Cells

    PubMed Central

    Fischer, Kyra; Tognarelli, Sara; Roesler, Stefanie; Boedicker, Cathinka; Schubert, Ralf; Steinle, Alexander; Klingebiel, Thomas; Bader, Peter; Fulda, Simone; Ullrich, Evelyn

    2017-01-01

    Rhabdomyosarcoma (RMS), the most common cancer of connective tissues in pediatrics, is often resistant to conventional therapies. One underlying mechanism of this resistance is the overexpression of Inhibitor of Apoptosis (IAP) proteins, leading to a dysfunctional cell death program within tumor cells. Smac mimetics (SM) are small molecules that can reactivate the cell death program by antagonizing IAP proteins and thereby compensating their overexpression. Here, we report that SM sensitize two RMS cell lines (RD and RH30) toward natural killer (NK) cell-mediated killing on the one hand, and increase the cytotoxic potential of NK cells on the other. The SM-induced sensitization of RH30 cells toward NK cell-mediated killing is significantly reduced through blocking tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) on NK cells prior to coculture. In addition, the presence of zVAD.fmk, a pancaspase inhibitor, rescues tumor cells from the increase in killing, indicating an apoptosis-dependent cell death. On the NK cell side, the presence of SM in addition to IL-2 during the ex vivo expansion leads to an increase in their cytotoxic activity against RH30 cells. This effect is mainly TNFα-dependent and partially mediated by NK cell activation, which is associated with transcriptional upregulation of NF-κB target genes such as IκBα and RelB. Taken together, our findings implicate that SM represent a novel double-hit strategy, sensitizing tumor and activating NK cells with one single drug. PMID:28326081

  5. The Host Defense Peptide Cathelicidin Is Required for NK Cell-Mediated Suppression of Tumor Growth

    PubMed Central

    Büchau, Amanda S.; Morizane, Shin; Trowbridge, Janet; Schauber, Jürgen; Kotol, Paul; Bui, Jack D.; Gallo, Richard L.

    2010-01-01

    Tumor surveillance requires the interaction of multiple molecules and cells that participate in innate and the adaptive immunity. Cathelicidin was initially identified as an antimicrobial peptide, although it is now clear that it fulfills a variety of immune functions beyond microbial killing. Recent data have suggested contrasting roles for cathelicidin in tumor development. Because its role in tumor surveillance is not well understood, we investigated the requirement of cathelicidin in controlling transplantable tumors in mice. Cathelicidin was observed to be abundant in tumor-infiltrating NK1.1+ cells in mice. The importance of this finding was demonstrated by the fact that cathelicidin knockout mice (Camp−/−) permitted faster tumor growth than wild type controls in two different xenograft tumor mouse models (B16.F10 and RMA-S). Functional in vitro analyses found that NK cells derived from Camp−/− versus wild type mice showed impaired cytotoxic activity toward tumor targets. These findings could not be solely attributed to an observed perforin deficiency in freshly isolated Camp−/− NK cells, because this deficiency could be partially restored by IL-2 treatment, whereas cytotoxic activity was still defective in IL-2-activated Camp−/− NK cells. Thus, we demonstrate a previously unrecognized role of cathelicidin in NK cell antitumor function. PMID:19949065

  6. Modulation of CD112 by the alphaherpesvirus gD protein suppresses DNAM-1-dependent NK cell-mediated lysis of infected cells.

    PubMed

    Grauwet, Korneel; Cantoni, Claudia; Parodi, Monica; De Maria, Andrea; Devriendt, Bert; Pende, Daniela; Moretta, Lorenzo; Vitale, Massimo; Favoreel, Herman W

    2014-11-11

    Natural killer (NK) cells are key players in the innate response to viruses, including herpesviruses. In particular, the variety of viral strategies to modulate the recognition of certain herpesviruses witnesses the importance of NK cells in the control of this group of viruses. Still, NK evasion strategies have remained largely elusive for the largest herpesvirus subfamily, the alphaherpesviruses. Here, we report that the gD glycoprotein of the alphaherpesviruses pseudorabies virus (PRV) and herpes simplex virus 2 (HSV-2) displays previously uncharacterized immune evasion properties toward NK cells. Expression of gD during infection or transfection led to degradation and consequent down-regulation of CD112, a ligand for the activating NK receptor DNAX accessory molecule 1 (DNAM-1). CD112 downregulation resulted in a reduced ability of DNAM-1 to bind to the surface of both virus-infected and gD-transfected cells. Consequently, expression of gD suppressed NK cell degranulation and NK cell-mediated lysis of PRV- or HSV-2-infected cells. These data identify an alphaherpesvirus evasion strategy from NK cells and point out that interactions between viral envelope proteins and host cell receptors can have biological consequences that stretch beyond virus entry.

  7. NK cell subsets in autoimmune diseases.

    PubMed

    Zhang, Cai; Tian, Zhigang

    2017-03-09

    Natural killer (NK) cells are lymphocytes of the innate immune system. They not only exert cell-mediated cytotoxicity against tumor cells or infected cells, but also play regulatory role through promoting or suppressing functions of other immune cells by secretion of cytokines and chemokines. However, overactivation or dysfunction of NK cells may be associated with pathogenesis of some diseases. NK cells are found to act as a two edged weapon and play opposite roles with both regulatory and inducer activity in autoimmune diseases. Though the precise mechanisms for the opposite effects of NK cells has not been fully elucidated, the importance of NK cells in autoimmune diseases might be associated with different NK cell subsets, different tissue microenvironment and different stages of corresponding diseases. The local tissue microenvironment, unique cellular interactions and different stages of corresponding diseases shape the properties and function of NK cells. In this review, we focus on recent research on the features and function of different NK cell subsets, particularly tissue-resident NK cells in different tissues, and their potential role in autoimmune diseases.

  8. Hepatic NK cell-mediated hypersensitivity to ConA-induced liver injury in mouse liver expressing hepatitis C virus polyprotein.

    PubMed

    Fu, Qiuxia; Yan, Shaoduo; Wang, Licui; Duan, Xiangguo; Wang, Lei; Wang, Yue; Wu, Tao; Wang, Xiaohui; An, Jie; Zhang, Yulong; Zhou, Qianqian; Zhan, Linsheng

    2016-08-04

    The role of hepatic NK cells in the pathogenesis of HCV-associated hepatic failure is incompletely understood. In this study, we investigated the effect of HCV on ConA-induced immunological hepatic injury and the influence of HCV on hepatic NK cell activation in the liver after ConA administration. An immunocompetent HCV mouse model that encodes the entire viral polyprotein in a liver-specific manner based on hydrodynamic injection and φC31o integrase was used to study the role of hepatic NK cells. Interestingly, the frequency of hepatic NK cells was reduced in HCV mice, whereas the levels of other intrahepatic lymphocytes remained unaltered. Next, we investigated whether the reduction in NK cells within HCV mouse livers might elicit an effect on immune-mediated liver injury. HCV mice were subjected to acute liver injury models upon ConA administration. We observed that HCV mice developed more severe ConA-induced immune-mediated hepatitis, which was dependent on the accumulated intrahepatic NK cells. Our results indicated that after the administration of ConA, NK cells not only mediated liver injury through the production of immunoregulatory cytokines (IFN-γ, TNF-α and perforin) with direct antiviral activity, but they also killed target cells directly through the TRAIL/DR5 and NKG2D/NKG2D ligand signaling pathway in HCV mice. Our findings suggest a critical role for NK cells in oversensitive liver injury during chronic HCV infection.

  9. NK cells modulate the lung dendritic cell-mediated Th1/Th17 immunity during intracellular bacterial infection.

    PubMed

    Shekhar, Sudhanshu; Peng, Ying; Gao, Xiaoling; Joyee, Antony G; Wang, Shuhe; Bai, Hong; Zhao, Lei; Yang, Jie; Yang, Xi

    2015-10-01

    The impact of the interaction between NK cells and lung dendritic cells (LDCs) on the outcome of respiratory infections is poorly understood. In this study, we investigated the effect and mechanism of NK cells on the function of LDCs during intracellular bacterial lung infection of Chlamydia muridarum in mice. We found that the naive mice receiving LDCs from C. muridarum-infected NK-cell-depleted mice (NK-LDCs) showed more serious body weight loss, bacterial burden, and pathology upon chlamydial challenge when compared with the recipients of LDCs from infected sham-treated mice (NK+LDCs). Cytokine analysis of the local tissues of the former compared with the latter exhibited lower levels of Th1 (IFN-γ) and Th17 (IL-17), but higher levels of Th2 (IL-4), cytokines. Consistently, NK-LDCs were less efficient in directing C. muridarum-specific Th1 and Th17 responses than NK+LDCs when cocultured with CD4(+) T cells. In NK cell/LDC coculture experiments, the blockade of NKG2D receptor reduced the production of IL-12p70, IL-6, and IL-23 by LDCs. The neutralization of IFN-γ in the culture decreased the production of IL-12p70 by LDCs, whereas the blockade of TNF-α resulted in diminished IL-6 production. Our findings demonstrate that NK cells modulate LDC function to elicit Th1/Th17 immunity during intracellular bacterial infection.

  10. Obinutuzumab-mediated high-affinity ligation of FcγRIIIA/CD16 primes NK cells for IFNγ production

    PubMed Central

    Capuano, Cristina; Pighi, Chiara; Molfetta, Rosa; Paolini, Rossella; Battella, Simone; Palmieri, Gabriella; Santoni, Angela; Galandrini, Ricciarda

    2017-01-01

    ABSTRACT Natural killer (NK) cell-mediated antibody-dependent cellular cytotoxicity (ADCC), based on the recognition of IgG-opsonized targets by the low-affinity receptor for IgG FcγRIIIA/CD16, represents one of the main mechanisms by which therapeutic antibodies (mAbs) mediate their antitumor effects. Besides ADCC, CD16 ligation also results in cytokine production, in particular, NK-derived IFNγ is endowed with a well-recognized role in the shaping of adaptive immune responses. Obinutuzumab is a glycoengineered anti-CD20 mAb with a modified crystallizable fragment (Fc) domain designed to increase the affinity for CD16 and consequently the killing of mAb-opsonized targets. However, the impact of CD16 ligation in optimized affinity conditions on NK functional program is not completely understood. Herein, we demonstrate that the interaction of NK cells with obinutuzumab-opsonized cells results in enhanced IFNγ production as compared with parental non-glycoengineered mAb or the reference molecule rituximab. We observed that affinity ligation conditions strictly correlate with the ability to induce CD16 down-modulation and lysosomal targeting of receptor-associated signaling elements. Indeed, a preferential degradation of FcεRIγ chain and Syk kinase was observed upon obinutuzumab stimulation independently from CD16-V158F polymorphism. Although the downregulation of FcεRIγ/Syk module leads to the impairment of cytotoxic function induced by NKp46 and NKp30 receptors, obinutuzumab-experienced cells exhibit an increased ability to produce IFNγ in response to different stimuli. These data highlight a relationship between CD16 aggregation conditions and the ability to promote a degradative pathway of CD16-coupled signaling elements associated to the shift of NK functional program.

  11. Genetic Causes of Human NK Cell Deficiency and Their Effect on NK Cell Subsets.

    PubMed

    Mace, Emily M; Orange, Jordan S

    2016-01-01

    Human NK cells play critical roles in human host defense, particularly the control of viral infection and malignancy, and patients with congenital immunodeficiency affecting NK cell function or number can suffer from severe illness. The importance of NK cell function is particularly underscored in patients with primary immunodeficiency in which NK cells are the primary or sole affected population (NK cell deficiency, NKD). While NKD may lead to the absence of NK cells, we are also gaining an increasing appreciation of the effect that NKD may have on the generation of specific NK cell subsets. In turn, this leads to improved insights into the requirements for human NK cell subset generation, as well as their importance in immune homeostasis. The presence of inherently abnormally developed or functionally impaired NK cells, in particular, appears to be problematic in the way of interfering with normal human host defense and may be more impactful than low numbers of NK cells alone. Here, we review the known genetic causes of NKD and the insight that is derived by these into the requirements for human subset generation and, by extension, for NK cell-mediated immunity.

  12. Genetic Causes of Human NK Cell Deficiency and Their Effect on NK Cell Subsets

    PubMed Central

    Mace, Emily M.; Orange, Jordan S.

    2016-01-01

    Human NK cells play critical roles in human host defense, particularly the control of viral infection and malignancy, and patients with congenital immunodeficiency affecting NK cell function or number can suffer from severe illness. The importance of NK cell function is particularly underscored in patients with primary immunodeficiency in which NK cells are the primary or sole affected population (NK cell deficiency, NKD). While NKD may lead to the absence of NK cells, we are also gaining an increasing appreciation of the effect that NKD may have on the generation of specific NK cell subsets. In turn, this leads to improved insights into the requirements for human NK cell subset generation, as well as their importance in immune homeostasis. The presence of inherently abnormally developed or functionally impaired NK cells, in particular, appears to be problematic in the way of interfering with normal human host defense and may be more impactful than low numbers of NK cells alone. Here, we review the known genetic causes of NKD and the insight that is derived by these into the requirements for human subset generation and, by extension, for NK cell-mediated immunity. PMID:27994588

  13. NKp46-mediated Dicer1 inactivation results in defective NK-cell differentiation and effector functions in mice.

    PubMed

    Degouve, Sophie; Tavares, Armelle; Viel, Sébastien; Walzer, Thierry; Marçais, Antoine

    2016-08-01

    MicroRNAs control developmental pathways and effector functions in immune cells. Previous studies have studied the role of microRNAs in natural killer (NK) cells. However, the mouse models of microRNA depletion used were nonNK-specific and only partially depleting, hampering the interpretation of the data obtained. To clarify the role of microRNAs in murine NK cells, we deleted the RNase III enzyme Dicer1 in NKp46-expressing cells. We observed a drastic decrease in several microRNAs specifically in NK cells. Furthermore, the overall size of the "NK-cell" pool was severely decreased, a phenotype associated with compromised survival. Moreover, performing a broad flow cytometry profiling, we show that Dicer1-deficient NK cells failed to complete their differentiation program. In particular, several integrins were inappropriately expressed in mature NK cells. These defects coincided with decreased response to IL-15, a cytokine responsible for "NK-cell" maturation and survival. In addition, Dicer1 deletion impaired key "NK-cell" functions: target cell killing and production of IFN-γ, leading to defective control of metastasis. Dicer1 deletion thus affects "NK-cell" biology in a cell intrinsic manner at several distinct stages.

  14. Activation of NK cell cytotoxicity by aerosolized CpG-ODN/poly(I:C) against lung melanoma metastases is mediated by alveolar macrophages.

    PubMed

    Sommariva, Michele; Le Noci, Valentino; Storti, Chiara; Bianchi, Francesca; Tagliabue, Elda; Balsari, Andrea; Sfondrini, Lucia

    2017-03-01

    Controversies remain about NK cells direct responsiveness to Toll-like receptor (TLR) agonists or dependence on macrophages. In a melanoma lung metastasis model, aerosolized TLR9 and TLR3 agonists have been reported to induce antitumor immunity through NK cells activation. In the current study, we demonstrated that in vitro TLR9/TLR3 stimulation induced IFN-γ secretion by NK cells, but an increase in their cytotoxicity was detected only after NK cells co-culture with in vitro TLR9/TLR3 agonists pretreated alveolar macrophages. Alveolar macrophages from melanoma lung metastases-bearing mice, treated with aerosolized TLR agonists, also promoted NK cell cytotoxicity. Activated NK cells from lungs of melanoma metastases-bearing mice that were given aerosolized TLR9/TLR3 agonists were able to polarize naive alveolar macrophages toward a M1-like phenotype. Our results demonstrate that activation of NK cells in the lung after TLR engagement is mediated by alveolar macrophages and that activated NK cells shape macrophage behavior.

  15. Type I IFN promotes NK cell expansion during viral infection by protecting NK cells against fratricide.

    PubMed

    Madera, Sharline; Rapp, Moritz; Firth, Matthew A; Beilke, Joshua N; Lanier, Lewis L; Sun, Joseph C

    2016-02-08

    Type I interferon (IFN) is crucial in host antiviral defense. Previous studies have described the pleiotropic role of type I IFNs on innate and adaptive immune cells during viral infection. Here, we demonstrate that natural killer (NK) cells from mice lacking the type I IFN-α receptor (Ifnar(-/-)) or STAT1 (which signals downstream of IFNAR) are defective in expansion and memory cell formation after mouse cytomegalovirus (MCMV) infection. Despite comparable proliferation, Ifnar(-/-) NK cells showed diminished protection against MCMV infection and exhibited more apoptosis compared with wild-type NK cells. Furthermore, we show that Ifnar(-/-) NK cells express increased levels of NK group 2 member D (NKG2D) ligands during viral infection and are susceptible to NK cell-mediated fratricide in a perforin- and NKG2D-dependent manner. Adoptive transfer of Ifnar(-/-) NK cells into NK cell-deficient mice reverses the defect in survival and expansion. Our study reveals a novel type I IFN-dependent mechanism by which NK cells evade mechanisms of cell death after viral infection.

  16. The rapid rejection of allogeneic lymphocytes by a non-adaptive, cell-mediated mechanism (NK activity).

    PubMed Central

    Rolstad, B; Fossum, S; Bazin, H; Kimber, I; Marshall, J; Sparshott, S M; Ford, W L

    1985-01-01

    The fate of allogeneic lymphocytes (AO or DA) transferred to non-immune PVG recipients was studied in the light of previous evidence (Heslop & McNeilage, 1983; Rolstad & Ford, 1983) that allogeneic lymphocytes can be rapidly destroyed in certain strain combinations of rats and mice by a mechanism that is distinct from either T-cell mediated immunity or an alloantibody response. AO lymphocytes injected into PVG recipients were discriminated from syngeneic lymphocytes within 15-30 min of i.v. injection, as testified by the excess release of 51Cr into the lymph plasma of the recipient. The following experiments were intended to distinguish between natural antibody and natural killer (NK) cells as the mechanism responsible for the allogeneic lymphocyte cytotoxicity (ALC) displayed by PVG rats. Nude rats treated from birth with anti-mu chain serum and shown to be lacking B and T lymphocytes, as well as being profoundly deficient in immunoglobulin, displayed more aggressive ALC than did control nude rats which, in turn, showed stronger ALC than did euthymic rats. Serum from PVG nude rats exerted no inhibitory or destructive effect on allogeneic lymphocytes in an antibody-dependent cellular cytotoxicity system, an assay of graft-versus-host activity, or when injected into 3-4-week-old PVG rats which had not yet developed ALC. Treatment of nude rats with anti-asialo GM 1 antiserum depressed ALC and NK activity in parallel, thus adding to a wide range of circumstances in which ALC and NK activity are closely correlated. In conclusion, ALC is implemented by a non-adaptive, cell-mediated mechanism independent of immunoglobulin, but the precise identity of the effector cell in the recipients' lymphatic tissues remains to be settled. Images Figure 2 PMID:3972430

  17. Multi-cellular natural killer (NK) cell clusters enhance NK cell activation through localizing IL-2 within the cluster

    PubMed Central

    Kim, Miju; Kim, Tae-Jin; Kim, Hye Mi; Doh, Junsang; Lee, Kyung-Mi

    2017-01-01

    Multi-cellular cluster formation of natural killer (NK) cells occurs during in vivo priming and potentiates their activation to IL-2. However, the precise mechanism underlying this synergy within NK cell clusters remains unclear. We employed lymphocyte-laden microwell technologies to modulate contact-mediated multi-cellular interactions among activating NK cells and to quantitatively assess the molecular events occurring in multi-cellular clusters of NK cells. NK cells in social microwells, which allow cell-to-cell contact, exhibited significantly higher levels of IL-2 receptor (IL-2R) signaling compared with those in lonesome microwells, which prevent intercellular contact. Further, CD25, an IL-2R α chain, and lytic granules of NK cells in social microwells were polarized toward MTOC. Live cell imaging of lytic granules revealed their dynamic and prolonged polarization toward neighboring NK cells without degranulation. These results suggest that IL-2 bound on CD25 of one NK cells triggered IL-2 signaling of neighboring NK cells. These results were further corroborated by findings that CD25-KO NK cells exhibited lower proliferation than WT NK cells, and when mixed with WT NK cells, underwent significantly higher level of proliferation. These data highlights the existence of IL-2 trans-presentation between NK cells in the local microenvironment where the availability of IL-2 is limited. PMID:28074895

  18. Multi-cellular natural killer (NK) cell clusters enhance NK cell activation through localizing IL-2 within the cluster

    NASA Astrophysics Data System (ADS)

    Kim, Miju; Kim, Tae-Jin; Kim, Hye Mi; Doh, Junsang; Lee, Kyung-Mi

    2017-01-01

    Multi-cellular cluster formation of natural killer (NK) cells occurs during in vivo priming and potentiates their activation to IL-2. However, the precise mechanism underlying this synergy within NK cell clusters remains unclear. We employed lymphocyte-laden microwell technologies to modulate contact-mediated multi-cellular interactions among activating NK cells and to quantitatively assess the molecular events occurring in multi-cellular clusters of NK cells. NK cells in social microwells, which allow cell-to-cell contact, exhibited significantly higher levels of IL-2 receptor (IL-2R) signaling compared with those in lonesome microwells, which prevent intercellular contact. Further, CD25, an IL-2R α chain, and lytic granules of NK cells in social microwells were polarized toward MTOC. Live cell imaging of lytic granules revealed their dynamic and prolonged polarization toward neighboring NK cells without degranulation. These results suggest that IL-2 bound on CD25 of one NK cells triggered IL-2 signaling of neighboring NK cells. These results were further corroborated by findings that CD25-KO NK cells exhibited lower proliferation than WT NK cells, and when mixed with WT NK cells, underwent significantly higher level of proliferation. These data highlights the existence of IL-2 trans-presentation between NK cells in the local microenvironment where the availability of IL-2 is limited.

  19. "Natural Regulators": NK Cells as Modulators of T Cell Immunity.

    PubMed

    Schuster, Iona S; Coudert, Jerome D; Andoniou, Christopher E; Degli-Esposti, Mariapia A

    2016-01-01

    Natural killer (NK) cells are known as frontline responders capable of rapidly mediating a response upon encountering transformed or infected cells. Recent findings indicate that NK cells, in addition to acting as innate effectors, can also regulate adaptive immune responses. Here, we review recent studies on the immunoregulatory function of NK cells with a specific focus on their ability to affect the generation of early, as well as long-term antiviral T cell responses, and their role in modulating immune pathology and disease. In addition, we summarize the current knowledge of the factors governing regulatory NK cell responses and discuss origin, tissue specificity, and open questions about the classification of regulatory NK cells as classical NK cells versus group 1 innate lymphoid cells.

  20. Immunomodulatory properties of medicinal mushrooms: differential effects of water and ethanol extracts on NK cell-mediated cytotoxicity.

    PubMed

    Lu, Chia-Chen; Hsu, Ya-Jing; Chang, Chih-Jung; Lin, Chuan-Sheng; Martel, Jan; Ojcius, David M; Ko, Yun-Fei; Lai, Hsin-Chih; Young, John D

    2016-10-01

    Medicinal mushrooms have been used for centuries in Asian countries owing to their beneficial effects on health and longevity. Previous studies have reported that a single medicinal mushroom may produce both stimulatory and inhibitory effects on immune cells, depending on conditions, but the factors responsible for this apparent dichotomy remain obscure. We show here that water and ethanol extracts of cultured mycelium from various species (Agaricus blazei Murrill, Antrodia cinnamomea, Ganoderma lucidum and Hirsutella sinensis) produce opposite effects on NK cells. Water extracts enhance NK cell cytotoxic activity against cancer cells, whereas ethanol extracts inhibit cytotoxicity. Water extracts stimulate the expression and production of cytolytic proteins (perforin and granulysin) and NKG2D/NCR cell surface receptors, and activate intracellular signaling kinases (ERK, JNK and p38). In contrast, ethanol extracts inhibit expression of cytolytic and cell surface receptors. Our results suggest that the mode of extraction of medicinal mushrooms may determine the nature of the immunomodulatory effects produced on immune cells, presumably owing to the differential solubility of stimulatory and inhibitory mediators. These findings have important implications for the preparation of medicinal mushrooms to prevent and treat human diseases.

  1. Tetraspecific scFv construct provides NK cell mediated ADCC and self-sustaining stimuli via insertion of IL-15 as a cross-linker

    PubMed Central

    Schmohl, Joerg U.; Felices, Martin; Todhunter, Deborah; Taras, Elizabeth; Miller, Jeffrey S.; Vallera, Daniel A.

    2016-01-01

    Background The design of a highly effective anti-cancer immune-engager would include targeting of highly drug refractory cancer stem cells (CSC). The design would promote effective antibody-dependent cell-mediated cytotoxicity (ADCC) and simultaneously promote costimulation to expand and self-sustain the effector NK cell population. Based on our bispecific NK cell engager platform we constructed a tetraspecific killer engager (TetraKE) comprising single-chain variable fragments (scFvs) binding FcγRIII (CD16) on NK cells, EpCAM on carcinoma cells and CD133 on cancer stem cells in order to promote ADCC. Furthermore, an Interleukin (IL)-15-crosslinker enhanced NK cell related proliferation resulting in a highly active drug termed 1615EpCAM133. Results Proliferation assays showed TetraKE promoted proliferation and enhanced NK cell survival. Drug-target binding, NK cell related degranulation, and IFN-γ production was specific for both tumor related antigens in EpCAM and CD133 bearing cancer cell lines. The TetraKE showed higher killing activity and superior dose dependent degranulation. Cytokine profiling showed a moderately enhanced IFN-γ production, enhanced GM-CSF production, but no evidence of induction of excessive cytokine release. Methods Assembly and synthesis of hybrid genes encoding the TetraKE were performed using DNA shuffling and ligation. The TetraKE was tested for efficacy, specificity, proliferation, survival, and cytokine production using carcinoma cell lines and functional assays measuring NK cell activity. Conclusion 1615EpCAM133 combines improved induction of ADCC with enhanced proliferation, limited cytokine response, and prolonged survival and proliferation of NK cells. By linking scFv-related targeting of carcinoma and CSCs with a sustaining IL-15 signal, our new construct shows great promise to target cancer and CSCs. PMID:27650544

  2. In vitro VLA-4 blockade results in an impaired NK cell-mediated immune surveillance against melanoma.

    PubMed

    Gandoglia, Ilaria; Ivaldi, Federico; Carrega, Paolo; Armentani, Eric; Ferlazzo, Guido; Mancardi, Gianluigi; Kerlero de Rosbo, Nicole; Uccelli, Antonio; Laroni, Alice

    2017-01-01

    Natalizumab (NTZ) is a monoclonal antibody targeting the α4β1 integrin (CD49d/CD29), very late antigen-4 (VLA-4), which is approved for treatment of relapsing-remitting multiple sclerosis (RR-MS). A possible association between NTZ treatment and a higher risk of melanoma is under debate. Natural Killer (NK) cells, which express VLA-4, represent an innate barrier limiting spreading of melanoma under steady state conditions. Indeed, because of their expression of activating receptors, they are very efficient in recognizing and killing melanoma cells without the need of a previous priming. For this reason, we aimed at assessing whether NK-cell functions might be impaired by sustained exposure to NTZ. To investigate this possibility we isolated NK cells from healthy donors and tested their cytotoxic and migratory functions against primary melanoma cells derived from subcutaneous and lymph node metastases. Flow cytometry analysis demonstrated expression of CD49d on both freshly isolated NK cells and activated NK cells. Moreover, VLA-4 and its receptor, vascular cell adhesion protein-1 (VCAM-1) were similarly expressed on freshly isolated NK cells. However, upon a short exposure to NTZ, expression of VLA-4 on NK cells decreased. Analysis of NK receptor expression upon exposure of NK cells from three healthy donors to NTZ indicated that DNAM-1 and NKp46 are apparently decreased, while NKG2A is increased. The degranulation of NK cells towards melanoma cells, which express both VLA-4 and VCAM-1, was not affected when NTZ was added to the co-culture or when both NK cells and melanoma cells were each pre-exposed to NTZ for over 12h. In contrast, degranulation was significantly inhibited after 48h of pre-incubation indicating that NTZ can influence NK-cell degranulation towards melanoma cells only after a prolonged exposure. Using a migration chamber assay, we observed that the migration of NK cells towards melanoma cells was dependent upon the concentration of melanoma

  3. Cognate HLA absence in trans diminishes human NK cell education

    PubMed Central

    Landtwing, Vanessa; Raykova, Ana; Pezzino, Gaetana; Béziat, Vivien; Graf, Claudine; Moretta, Alessandro; Capaul, Riccarda; Zbinden, Andrea; Malmberg, Karl-Johan; Chijioke, Obinna; Münz, Christian

    2016-01-01

    NK cells are innate lymphocytes with protective functions against viral infections and tumor formation. Human NK cells carry inhibitory killer cell Ig-like receptors (KIRs), which recognize distinct HLAs. NK cells with KIRs for self-HLA molecules acquire superior cytotoxicity against HLA– tumor cells during education for improved missing-self recognition. Here, we reconstituted mice with human hematopoietic cells from donors with homozygous KIR ligands or with a mix of hematopoietic cells from these homozygous donors, allowing assessment of the resulting KIR repertoire and NK cell education. We found that co-reconstitution with 2 KIR ligand–mismatched compartments did not alter the frequency of KIR-expressing NK cells. However, NK cell education was diminished in mice reconstituted with parallel HLA compartments due to a lack of cognate HLA molecules on leukocytes for the corresponding KIRs. This change in NK cell education in mixed human donor–reconstituted mice improved NK cell–mediated immune control of EBV infection, indicating that mixed hematopoietic cell populations could be exploited to improve NK cell reactivity against leukotropic pathogens. Taken together, these findings indicate that leukocytes lacking cognate HLA ligands can disarm KIR+ NK cells in a manner that may decrease HLA– tumor cell recognition but allows for improved NK cell–mediated immune control of a human γ-herpesvirus. PMID:27571408

  4. Bisphosphonate-induced differential modulation of immune cell function in gingiva and bone marrow in vivo: role in osteoclast-mediated NK cell activation.

    PubMed

    Tseng, Han-Ching; Kanayama, Keiichi; Kaur, Kawaljit; Park, So-Hyun; Park, Sil; Kozlowska, Anna; Sun, Shuting; McKenna, Charles E; Nishimura, Ichiro; Jewett, Anahid

    2015-08-21

    The aim of this study is to establish osteoclasts as key immune effectors capable of activating the function of Natural Killer (NK) cells, and expanding their numbers, and to determine in vivo and in vitro effect of bisphosphonates (BPs) during NK cell interaction with osteoclasts and on systemic and local immune function. The profiles of 27 cytokines, chemokines and growth factors released from osteoclasts were found to be different from dendritic cells and M1 macrophages but resembling to untreated monocytes and M2 macrophages. Nitrogen-containing BPs Zoledronate (ZOL) and Alendronate (ALN), but not non-nitrogen-containing BPs Etidronate (ETI), triggered increased release of pro-inflammatory mediators from osteoclasts while all three BPs decreased pit formation by osteoclasts. ZOL and ALN mediated significant release of IL-6, TNF-` and IL-1β, whereas they inhibited IL-10 secretion by osteoclasts. Treatment of osteoclasts with ZOL inhibited NK cell mediated cytotoxicity whereas it induced significant secretion of cytokines and chemokines. NK cells lysed osteoclasts much more than their precursor cells monocytes, and this correlated with the decreased expression of MHC class I expression on osteoclasts. Intravenous injection of ZOL in mice induced pro-inflammatory microenvironment in bone marrow and demonstrated significant immune activation. By contrast, tooth extraction wound of gingival tissues exhibited profound immune suppressive microenvironment associated with dysregulated wound healing to the effect of ZOL which could potentially be responsible for the pathogenesis of Osteonecrosis of the Jaw (ONJ). Finally, based on the data obtained in this paper we demonstrate that osteoclasts can be used as targets for the expansion of NK cells with superior function for immunotherapy of cancer.

  5. Bystander cells enhance NK cytotoxic efficiency by reducing search time.

    PubMed

    Zhou, Xiao; Zhao, Renping; Schwarz, Karsten; Mangeat, Matthieu; Schwarz, Eva C; Hamed, Mohamed; Bogeski, Ivan; Helms, Volkhard; Rieger, Heiko; Qu, Bin

    2017-03-13

    Natural killer (NK) cells play a central role during innate immune responses by eliminating pathogen-infected or tumorigenic cells. In the microenvironment, NK cells encounter not only target cells but also other cell types including non-target bystander cells. The impact of bystander cells on NK killing efficiency is, however, still elusive. In this study we show that the presence of bystander cells, such as P815, monocytes or HUVEC, enhances NK killing efficiency. With bystander cells present, the velocity and persistence of NK cells were increased, whereas the degranulation of lytic granules remained unchanged. Bystander cell-derived H2O2 was found to mediate the acceleration of NK cell migration. Using mathematical diffusion models, we confirm that local acceleration of NK cells in the vicinity of bystander cells reduces their search time to locate target cells. In addition, we found that integrin β chains (β1, β2 and β7) on NK cells are required for bystander-enhanced NK migration persistence. In conclusion, we show that acceleration of NK cell migration in the vicinity of H2O2-producing bystander cells reduces target cell search time and enhances NK killing efficiency.

  6. Bystander cells enhance NK cytotoxic efficiency by reducing search time

    PubMed Central

    Zhou, Xiao; Zhao, Renping; Schwarz, Karsten; Mangeat, Matthieu; Schwarz, Eva C.; Hamed, Mohamed; Bogeski, Ivan; Helms, Volkhard; Rieger, Heiko; Qu, Bin

    2017-01-01

    Natural killer (NK) cells play a central role during innate immune responses by eliminating pathogen-infected or tumorigenic cells. In the microenvironment, NK cells encounter not only target cells but also other cell types including non-target bystander cells. The impact of bystander cells on NK killing efficiency is, however, still elusive. In this study we show that the presence of bystander cells, such as P815, monocytes or HUVEC, enhances NK killing efficiency. With bystander cells present, the velocity and persistence of NK cells were increased, whereas the degranulation of lytic granules remained unchanged. Bystander cell-derived H2O2 was found to mediate the acceleration of NK cell migration. Using mathematical diffusion models, we confirm that local acceleration of NK cells in the vicinity of bystander cells reduces their search time to locate target cells. In addition, we found that integrin β chains (β1, β2 and β7) on NK cells are required for bystander-enhanced NK migration persistence. In conclusion, we show that acceleration of NK cell migration in the vicinity of H2O2-producing bystander cells reduces target cell search time and enhances NK killing efficiency. PMID:28287155

  7. RAET1E2, a soluble isoform of the UL16-binding protein RAET1E produced by tumor cells, inhibits NKG2D-mediated NK cytotoxicity.

    PubMed

    Cao, Wei; Xi, Xueyan; Hao, Zhiyong; Li, Wenjing; Kong, Yan; Cui, Lianxian; Ma, Chi; Ba, Denian; He, Wei

    2007-06-29

    UL16-binding proteins (ULBPs, also termed as retinoic acid early transcripts, encoded by RAET1 genes), a family of ligands for NKG2D in humans, are frequently expressed by tumor cells and mediate cytotoxicities of natural killer (NK) cells and CD8(+) alphabeta T cells to tumor cells. ULBP1, ULBP2, ULBP3, and RAET1L link to membrane through glycosylphosphatidylinositol, whereas RAET1E and RAET1G contain transmembrane and cytoplasmic domains. Proteolytic cleavage of ULBP2 produces truncated and soluble forms that may counteract NKG2D-mediated tumor immune surveillance. In this study, we report that RAET1E can produce a soluble, 35-kDa protein (termed as RAET1E2) lacking the transmembrane region by selective splicing in tumor cells. The expressions of both RAET1E2 transcripts and protein can be found in different tumor cells and tissues. Preincubation of NK-92 cells, a human NK cell line, with culture supernatants from tumor cell lines expressing RAET1E2 or RAET1E2 gene-transfected COS-7 cells resulted in decreased expression of NKG2D on NK-92 cells. Furthermore, incubation of NK-92 cells with recombinant RAET1E2 protein also decreased the surface expression of NKG2D and resulted in marked reduction in cytotoxicities to MGC-803, HepG2, or K562 tumor cells. Taken together, our data provide strong evidence for an immune escape mechanism of tumors via alternative splicing of ULBP RNA to generate a free soluble ULBP protein, RAET1E2, that may impair NKG2D-mediated NK cell cytotoxicity to tumors.

  8. NK cell cytotoxicity mediated by 2B4 and NTB-A is dependent on SAP acting downstream of receptor phosphorylation.

    PubMed

    Meinke, Stephan; Watzl, Carsten

    2013-01-01

    2B4 (CD244) and NK-T-B-antigen (NTB-A, CD352) are activating receptors on human natural killer (NK) cells and belong to the family of signaling lymphocyte activation molecule (SLAM)-related receptors (SRR). Engagement of these receptors leads to phosphorylation of their cytoplasmic tails and recruitment of the adapter proteins SLAM-associated protein (SAP) and Ewing's sarcoma-activated transcript-2 (EAT-2). X-linked lymphoproliferative syndrome (XLP) is a severe immunodeficiency that results from mutations in the SAP gene. 2B4 and NTB-A-mediated cytotoxicity are abrogated in XLP NK cells. To elucidate the molecular basis for this defect we analyzed early signaling events in SAP knockdown cells. Similar to XLP NK cells, knockdown of SAP in primary human NK cells leads to a reduction of 2B4 and NTB-A-mediated cytotoxicity. We found that early signaling events such as raft recruitment and receptor phosphorylation are not affected by the absence of SAP, indicating the defect in the absence of SAP is downstream of these events. In addition, knockdown of EAT-2 does not impair 2B4 or NTB-A-mediated cytotoxicity. Surprisingly, EAT-2 recruitment to both receptors is abrogated in the absence of SAP, revealing a novel cooperativity between these adapters.

  9. Complement regulates conventional DC-mediated NK-cell activation by inducing TGF-β1 in Gr-1+ myeloid cells.

    PubMed

    Qing, Xiaoping; Koo, Gloria C; Salmon, Jane E

    2012-07-01

    Complement activation modulates DC-mediated T-cell activation, but whether complement affects DC-mediated priming of NK cells is unknown. Here, we demonstrated that conventional DCs (cDCs) from C3(-/-) and C5aR(-/-) mice are hyperresponsive to polyI:C, a TLR3 ligand, leading to enhanced NK-cell activation. We found that cDCs lack C5a receptor (C5aR) and do not respond to C5a directly. Depletion of Gr-1(+) myeloid cells augments polyI:C-induced cDC activation in WT but not in C3(-/-) or C5aR(-/-) mice, indicating that the effect of complement activation on cDCs is indirectly mediated through C5aR-expressing Gr-1(+) myeloid cells. We further demonstrated that the mechanism by which Gr-1(+) myeloid cells regulate the activity of cDCs involves C5a-dependent TGF-β1 production in Gr-1(+) myeloid cells. C5a enhances and blocking C5aR decreases TGF-β1 production in cultured bone marrow Gr-1(+) CD11b(+) cells. C5aR deficiency is associated with reduced circulating TGF-β1 levels, while depleting Gr-1(+) myeloid cells abrogates this difference between WT and C5aR(-/-) mice. Lastly, we showed that enhanced cDC-NK-cell activity in C3(-/-) mice led to delayed melanoma tumor growth. Thus, complement activation indirectly regulates cDC-NK-cell activation in response to inflammatory stimuli such as TLR3 by promoting TGF-β1 production in Gr-1(+) myeloid cells at steady state.

  10. PILRα binds an unknown receptor expressed primarily on CD56bright and decidual-NK cells and activates NK cell functions.

    PubMed

    Ophir, Yael; Duev-Cohen, Alexandra; Yamin, Rachel; Tsukerman, Pini; Bauman, Yoav; Gamliel, Moriya; Mandelboim, Ofer

    2016-07-05

    Natural Killer (NK) cells are innate immune lymphocytes specializing in recognition and killing of tumors and pathogens, using an array of activating and inhibitory receptors. NK inhibition is mediated by a large repertoire of inhibitory receptors, whereas a limited number of activating NK cell receptors execute NK cell activation. The ligands recognized by the activating receptors are stress-induced, pathogen derived, tumor specific and even self ligands. However, the full spectrum of NK cell receptors and ligands that control NK cell activity remains uncharacterized. Here we demonstrate that Paired Ig-Like type 2 Receptor Alpha (PILRα), binds a distinct human NK cell sub-population present in the peripheral blood and also in the decidua. We further demonstrate that the interaction of NK cells with PILRα expressing targets lead to elevated IFNγ secretion and cytotoxicity. In conclusion, we present here a novel NK activating ligand which binds and activates an unknown NK receptor expressed on a unique NK cell subset.

  11. The natural product phyllanthusmin C enhances IFN-γ production by human NK cells through upregulation of TLR-mediated NF-κB signaling.

    PubMed

    Deng, Youcai; Chu, Jianhong; Ren, Yulin; Fan, Zhijin; Ji, Xiaotian; Mundy-Bosse, Bethany; Yuan, Shunzong; Hughes, Tiffany; Zhang, Jianying; Cheema, Baljash; Camardo, Andrew T; Xia, Yong; Wu, Lai-Chu; Wang, Li-Shu; He, Xiaoming; Kinghorn, A Douglas; Li, Xiaohui; Caligiuri, Michael A; Yu, Jianhua

    2014-09-15

    Natural products are a major source for cancer drug development. NK cells are a critical component of innate immunity with the capacity to destroy cancer cells, cancer-initiating cells, and clear viral infections. However, few reports describe a natural product that stimulates NK cell IFN-γ production and unravel a mechanism of action. In this study, through screening, we found that a natural product, phyllanthusmin C (PL-C), alone enhanced IFN-γ production by human NK cells. PL-C also synergized with IL-12, even at the low cytokine concentration of 0.1 ng/ml, and stimulated IFN-γ production in both human CD56(bright) and CD56(dim) NK cell subsets. Mechanistically, TLR1 and/or TLR6 mediated PL-C's activation of the NF-κB p65 subunit that in turn bound to the proximal promoter of IFNG and subsequently resulted in increased IFN-γ production in NK cells. However, IL-12 and IL-15Rs and their related STAT signaling pathways were not responsible for the enhanced IFN-γ secretion by PL-C. PL-C induced little or no T cell IFN-γ production or NK cell cytotoxicity. Collectively, we identify a natural product with the capacity to selectively enhance human NK cell IFN-γ production. Given the role of IFN-γ in immune surveillance, additional studies to understand the role of this natural product in prevention of cancer or infection in select populations are warranted.

  12. Effect of Fibroblast-Like Cells of Mesenchymal Origin of Cytotoxic Activity of Lymphocytes against NK-Sensitive Target Cells.

    PubMed

    Lupatov, A Yu; Kim, Ya S; Bystrykh, O A; Vakhrushev, I V; Pavlovich, S V; Yarygin, K N; Sukhikh, G T

    2017-02-01

    We studied immunosuppressive properties of skin fibroblasts and mesenchymal stromal cells against NK cells. In vitro experiments showed that mesenchymal stromal cells isolated from human umbilical cord and human skin fibroblasts can considerably attenuate cytotoxic activity of NK cells against Jurkat cells sensitive to NK-mediated lysis. NK cells cultured in lymphocyte population exhibited higher cytotoxic activity than isolated NK cells. Mesenchymal stromal cells or fibroblasts added 1:1 to lymphocyte culture almost completely suppressed NK cell cytotoxicity. This suggests that fibroblast-like cells can suppress not only isolated NK cells, but also NK cells in natural cell microenvironment.

  13. IL-27 stimulates human NK-cell effector functions and primes NK cells for IL-18 responsiveness.

    PubMed

    Ziblat, Andrea; Domaica, Carolina I; Spallanzani, Raúl G; Iraolagoitia, Ximena L Raffo; Rossi, Lucas E; Avila, Damián E; Torres, Nicolás I; Fuertes, Mercedes B; Zwirner, Norberto W

    2015-01-01

    IL-27, a member of the IL-12 family of cytokines, is produced by APCs, and displays pro- and anti-inflammatory effects. How IL-27 affects human NK cells still remains unknown. In this study, we observed that mature DCs secreted IL-27 and that blockade of IL-27R (CD130) reduced the amount of IFN-γ produced by NK cells during their coculture, showing the importance of IL-27 during DC-NK-cell crosstalk. Accordingly, human rIL-27 stimulated IFN-γ secretion by NK cells in a STAT1-dependent manner, induced upregulation of CD25 and CD69 on NK cells, and displayed a synergistic effect with IL-18. Preincubation experiments demonstrated that IL-27 primed NK cells for IL-18-induced IFN-γ secretion, which was associated with an IL-27-driven upregulation of T-bet expression. Also, IL-27 triggered NKp46-dependent NK-cell-mediated cytotoxicity against Raji, T-47D, and HCT116 cells, and IL-18 enhanced this cytotoxic response. Such NK-cell-mediated cytotoxicity involved upregulation of perforin, granule exocytosis, and TRAIL-mediated cytotoxicity but not Fas-FasL interaction. Moreover, IL-27 also potentiated Ab-dependent cell-mediated cytotoxicity against mAb-coated target cells. Taken together, IL-27 stimulates NK-cell effector functions, which might be relevant in different physiological and pathological situations.

  14. Augmented IFN-γ and TNF-α Induced by Probiotic Bacteria in NK Cells Mediate Differentiation of Stem-Like Tumors Leading to Inhibition of Tumor Growth and Reduction in Inflammatory Cytokine Release; Regulation by IL-10

    PubMed Central

    Bui, Vickie T.; Tseng, Han-Ching; Kozlowska, Anna; Maung, Phyu Ou; Kaur, Kawaljit; Topchyan, Paytsar; Jewett, Anahid

    2015-01-01

    Our previous reports demonstrated that the magnitude of natural killer (NK) cell-mediated cytotoxicity correlate directly with the stage and level of differentiation of tumor cells. In addition, we have shown previously that activated NK cells inhibit growth of cancer cells through induction of differentiation, resulting in the resistance of tumor cells to NK cell-mediated cytotoxicity through secreted cytokines, as well as direct NK-tumor cell contact. In this report, we show that in comparison to IL-2 + anti-CD16mAb-treated NK cells, activation of NK cells by probiotic bacteria (sAJ2) in combination with IL-2 and anti-CD16mAb substantially decreases tumor growth and induces maturation, differentiation, and resistance of oral squamous cancer stem cells, MIA PaCa-2 stem-like/poorly differentiated pancreatic tumors, and healthy stem cells of apical papillae through increased secretion of IFN-γ and TNF-α, as well as direct NK-tumor cell contact. Tumor resistance to NK cell-mediated killing induced by IL-2 + anti-CD16mAb + sAJ2-treated NK cells is induced by combination of IFN-γ and TNF-α since antibodies to both, and not each cytokine alone, were able to restore tumor sensitivity to NK cells. Increased surface expression of CD54, B7H1, and MHC-I on NK-differentiated tumors was mediated by IFN-γ since the addition of anti-IFN-γ abolished their increase and restored the ability of NK cells to trigger cytokine and chemokine release; whereas differentiated tumors inhibited cytokine release by the NK cells. Monocytes synergize with NK cells in the presence of probiotic bacteria to induce regulated differentiation of stem cells through secretion of IL-10 resulting in resistance to NK cell-mediated cytotoxicity and inhibition of cytokine release. Therefore, probiotic bacteria condition activated NK cells to provide augmented differentiation of cancer stem cells resulting in inhibition of tumor growth, and decreased inflammatory cytokine release. PMID

  15. The CC chemokine CK beta-11/MIP-3 beta/ELC/Exodus 3 mediates tumor rejection of murine breast cancer cells through NK cells.

    PubMed

    Braun, S E; Chen, K; Foster, R G; Kim, C H; Hromas, R; Kaplan, M H; Broxmeyer, H E; Cornetta, K

    2000-04-15

    CK beta-11 chemoattracts T cells, B cells, dendritic cells, macrophage progenitors, and NK cells and facilitates dendritic cell and T cell interactions in secondary lymphoid tissues. We hypothesized that expression of CK beta-11 in tumor cells may generate antitumor immunity through these interactions. After transduction with the retroviral vector L(CK beta 11)SN, the murine breast cancer cell line C3L5 (C3L5-CK beta 11) showed expression of retroviral mRNA by Northern analysis and production of functional CK beta-11 by chemotaxis of human NK cells to C3L5-CK beta 11 supernatant. Only 10% of mice injected with C3L5-CK beta 11 developed tumors, compared with 100% of mice injected with a transduced control C3L5 line (C3L5-G1N). Importantly, the in vitro growth characteristics of the CK beta-11-transduced cell line were unaffected, suggesting the difference in growth in vivo was a result of chemokine production. Vaccination with C3L5-CK beta 11 partially protected animals from parental C3L5 challenge. Immunodepletion with anti-asialo-GM1 or anti-CD4 during C3L5-CK beta 11 vaccination significantly reduced CK beta-11 antitumor activity compared with control and anti-CD8-treated groups. Splenocytes from NK-depleted animals transferred the acquired immunity generated with C3L5-CK beta 11 vaccination, while splenocytes from the CD4-depleted animals did not. These results indicate, for the first time, that expression of CK beta-11 in a breast cancer cell line mediates rejection of the transduced tumor through a mechanism involving NK and CD4+ cells. Furthermore, CK beta-11-transduced tumor cells generate long-term antitumor immunity that requires CD4+ cells. These studies demonstrate the potential role of CK beta-11 as an adjuvant in stimulating antitumor responses.

  16. Accessory Cell Mediated Activation of Porcine NK Cells by TLR7 and TLR8 Agonists

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The induction of innate immune responses by toll-like receptor (TLR) agonists is the subject of intense investigation in many different species. In large part, this reflects the potential of such compounds to be effective vaccine adjuvants. For that reason, we analyzed the activation of innate cells...

  17. Overexpression of CD85j in TNBC patients inhibits Cetuximab-mediated NK-cell ADCC but can be restored with CD85j functional blockade.

    PubMed

    Roberti, María P; Juliá, Estefanía P; Rocca, Yamila S; Amat, Mora; Bravo, Alicia I; Loza, José; Coló, Federico; Loza, Carlos M; Fabiano, Verónica; Maino, Mercedes; Podhorzer, Ariel; Fainboim, Leonardo; Barrio, María M; Mordoh, José; Levy, Estrella M

    2015-05-01

    Clinical studies suggest that triple negative breast cancer (TNBC) patients with epidermal growth factor receptor (EGFR)-expressing tumors could benefit from therapy with Cetuximab, which targets EGFR. NK cells are the primary effectors of antibody (Ab)-dependent cell-mediated cytotoxicity (ADCC) and thus play a role in Ab-based therapies. We have previously described diminished levels of Cetuximab-mediated ADCC in vitro in patients with advanced breast cancer. Here, we investigated the potential causes of this NK-cell functional deficiency. We characterized NK-cell activating/inhibitory receptors in the peripheral blood of breast cancer patients and found CD85j inhibitory receptor overexpression. The capacity of NK cells to perform Cetuximab-triggered ADCC against TNBC cells correlated inversely with CD85j expression, even in the presence of the stimulatory cytokines IL-2 or IL-15. Hence, patients expressing high levels of CD85j had an impaired ability to lyse TNBC cells in the presence of Cetuximab. We also found that CD85j overexpression was associated with HLA-I and soluble HLA-G expression by tumors. A CD85j functional blockade with a CD85j antagonist Ab restored ADCC levels in breast cancer patients and reverted this negative effect. Our data suggest that strategies that overcome the hurdles of immune activation could improve Cetuximab clinical efficacy.

  18. NK cells require antigen-specific memory CD4+ T cells to mediate superior effector functions during HSV-2 recall responses in vitro.

    PubMed

    Chen, Branson; Lee, Amanda J; Chew, Marianne V; Ashkar, Ali A

    2016-12-14

    Natural killer (NK) cells have an important role in mounting protective innate responses against genital herpes simplex virus type 2 (HSV-2) infections. However their role as effectors in adaptive immune responses against HSV-2 is unclear. Here, we demonstrate that NK cells from C57BL/6 mice in an ex vivo splenocyte culture produce significantly more interferon γ (IFN-γ) upon re-exposure to HSV-2 antigens in a mouse model of genital HSV-2 immunization. We find that naïve NK cells do not require any prior stimulation or priming to be activated to produce IFN-γ. Our results demonstrate that HSV-2-experienced CD4(+) T cells have a crucial role in coordinating NK cell activation and that their presence during HSV-2 antigen presentation is required to activate NK cells in this model of secondary immune response. We also examined the requirement of cell-to-cell contacts for both CD4(+) T cells and NK cells. NK cells are dependent on direct interactions with other HSV-2-experienced splenocytes, and CD4(+) T cells need to be in close proximity to NK cells to activate them. This study revealed that NK cells do not exhibit any memory toward HSV-2 antigens and, in fact, require specific interactions with HSV-2-experienced CD4(+) T cells to produce IFN-γ.

  19. Valproic Acid Upregulates NKG2D Ligand Expression through an ERK-dependent Mechanism and Potentially Enhances NK Cell-mediated Lysis of Myeloma1

    PubMed Central

    Wu, Xiaosong; Tao, Yi; Hou, Jun; Meng, Xiuqin; Shi, Jumei

    2012-01-01

    Modulation of the antitumor immune response through the engagement of NKG2D receptors with their ligands (L) on targets represents a promising therapeutic approach against cancer. In this study, we tested the effect of valproic acid (VPA), a histone deacetylase (HDAC) inhibitor, on the expression of NKG2D ligands in myeloma cells. We demonstrated that VPA was able to upregulate both protein and mRNA expression of major histocompatibility complex class I-related chain (MIC) A/B and UL16-binding protein (ULBP) 2 without any significant effect on the expression of ULBP1, ULBP3, and ULBP4 or induction of other natural killer (NK) cell ligands, such as NKp30-L, NKp44-L, and NKp46-L in myeloma cells. A 51Cr release assay and degranulation assay indicated that the induction of MICA/B and ULBP2 augmented NK cell-mediated lysis of myeloma cells, which was abolished by the addition of a blocking NKG2D antibody. Activation of constitutively phosphorylated extracellular signal-regulated kinase (ERK) by VPA is essential for the up-regulation of MICA/B and ULBP2 expressions. Inhibition of ERK using ERK inhibitor PD98059 decreased both MICA/B and ULBP2 expressions and NK cell cytotoxicity. Furthermore, overexpression of constitutively active ERK in ARK resulted in increased MICA/B and ULBP2 expressions and enhanced NK cell lysis. These data indicate that increased sensitivity of VPA-treated myeloma cells to NK cell lysis is caused by higher NKG2D ligand expression, resulting from more active ERK signaling pathway. Our results provide evidence that targeting ERK signaling pathway may be an additional mechanism supporting the antimyeloma activity of HDAC inhibitors and suggest its possible immunotherapeutic value for myeloma treatment. PMID:23308050

  20. CD56brightCD16- NK Cells Produce Adenosine through a CD38-Mediated Pathway and Act as Regulatory Cells Inhibiting Autologous CD4+ T Cell Proliferation.

    PubMed

    Morandi, Fabio; Horenstein, Alberto L; Chillemi, Antonella; Quarona, Valeria; Chiesa, Sabrina; Imperatori, Andrea; Zanellato, Silvia; Mortara, Lorenzo; Gattorno, Marco; Pistoia, Vito; Malavasi, Fabio

    2015-08-01

    Recent studies suggested that human CD56(bright)CD16(-) NK cells may play a role in the regulation of the immune response. Since the mechanism(s) involved have not yet been elucidated, in the present study we have investigated the role of nucleotide-metabolizing enzymes that regulate the extracellular balance of nucleotides/nucleosides and produce the immunosuppressive molecule adenosine (ADO). Peripheral blood CD56(dim)CD16(+) and CD56(bright)CD16(-) NK cells expressed similar levels of CD38. CD39, CD73, and CD157 expression was higher in CD56(bright)CD16(-) than in CD56(dim)CD16(+) NK cells. CD57 was mostly expressed by CD56(dim)CD16(+) NK cells. CD203a/PC-1 expression was restricted to CD56(bright)CD16(-) NK cells. CD56(bright)CD16(-) NK cells produce ADO and inhibit autologous CD4(+) T cell proliferation. Such inhibition was 1) reverted pretreating CD56(bright)CD16(-) NK cells with a CD38 inhibitor and 2) increased pretreating CD56(bright)CD16(-) NK cells with a nucleoside transporter inhibitor, which increase extracellular ADO concentration. CD56(bright)CD16(-) NK cells isolated from the synovial fluid of juvenile idiopathic arthritis patients failed to inhibit autologous CD4(+) T cell proliferation. Such functional impairment could be related to 1) the observed reduced CD38/CD73 expression, 2) a peculiar ADO production kinetics, and 3) a different expression of ADO receptors. In contrast, CD56(bright)CD16(-) NK cells isolated from inflammatory pleural effusions display a potent regulatory activity. In conclusion, CD56(bright)CD16(-) NK cells act as "regulatory cells" through ADO produced by an ectoenzymes network, with a pivotal role of CD38. This function may be relevant for the modulation of the immune response in physiological and pathological conditions, and it could be impaired during autoimmune/inflammatory diseases.

  1. The Fc-region of a new class of intact bispecific antibody mediates activation of accessory cells and NK cells and induces direct phagocytosis of tumour cells

    PubMed Central

    Zeidler, R; Mysliwietz, J; Csánady, M; Walz, A; Ziegler, I; Schmitt, B; Wollenberg, B; Lindhofer, H

    2000-01-01

    Bispecific antibodies (bsAb) are considered as promising tools for the elimination of disseminated tumour cells in a minimal residual disease situation. The bsAb-mediated recruitment of an immune effector cell in close vicinity of a tumour cell is thought to induce an antitumoural immune response. However, classical bispecific molecules activate only a single class of immune effector cell that may not yield optimal immune responses. We therefore constructed an intact bispecific antibody, BiUII (anti-CD3 × anti-EpCAM), that not only recognizes tumour cells and T lymphocytes with its two binding arms, but also binds and activates Fcγ-receptor positive accessory cells through its Fc-region. We have demonstrated recently that activated accessory cells contribute to the bsAb-induced antitumoural activity. We now analyse this stimulation in more detail and demonstrate here the BiUll-induced upregulation of activation markers like CD83 and CD95 on accessory cells and the induction of neopterin and biopterin synthesis. Experiments with pure cell subpopulations revealed binding of BiUll to CD64+ accessory cells and CD16+ NK cells, but not to CD32+ B lymphocytes. We provide further evidence for the importance of the Fc-region in that this bispecific molecule stimulates Fcγ-R-positive accessory cells to eliminate tumour cells in vitro by direct phagocytosis. © 2000 Cancer Research Campaign PMID:10901380

  2. NAP-2 Secreted by Human NK Cells Can Stimulate Mesenchymal Stem/Stromal Cell Recruitment.

    PubMed

    Almeida, Catarina R; Caires, Hugo R; Vasconcelos, Daniela P; Barbosa, Mário A

    2016-04-12

    Strategies for improved homing of mesenchymal stem cells (MSCs) to a place of injury are being sought and it has been shown that natural killer (NK) cells can stimulate MSC recruitment. Here, we studied the chemokines behind this recruitment. Assays were performed with bone marrow human MSCs and NK cells freshly isolated from healthy donor buffy coats. Supernatants from MSC-NK cell co-cultures can induce MSC recruitment but not to the same extent as when NK cells are present. Antibody arrays and ELISA assays confirmed that NK cells secrete RANTES (CCL5) and revealed that human NK cells secrete NAP-2 (CXCL7), a chemokine that can induce MSC migration. Inhibition with specific antagonists of CXCR2, a receptor that recognizes NAP-2, abolished NK cell-mediated MSC recruitment. This capacity of NK cells to produce chemokines that stimulate MSC recruitment points toward a role for this immune cell population in regulating tissue repair/regeneration.

  3. NAP-2 Secreted by Human NK Cells Can Stimulate Mesenchymal Stem/Stromal Cell Recruitment

    PubMed Central

    Almeida, Catarina R.; Caires, Hugo R.; Vasconcelos, Daniela P.; Barbosa, Mário A.

    2016-01-01

    Summary Strategies for improved homing of mesenchymal stem cells (MSCs) to a place of injury are being sought and it has been shown that natural killer (NK) cells can stimulate MSC recruitment. Here, we studied the chemokines behind this recruitment. Assays were performed with bone marrow human MSCs and NK cells freshly isolated from healthy donor buffy coats. Supernatants from MSC-NK cell co-cultures can induce MSC recruitment but not to the same extent as when NK cells are present. Antibody arrays and ELISA assays confirmed that NK cells secrete RANTES (CCL5) and revealed that human NK cells secrete NAP-2 (CXCL7), a chemokine that can induce MSC migration. Inhibition with specific antagonists of CXCR2, a receptor that recognizes NAP-2, abolished NK cell-mediated MSC recruitment. This capacity of NK cells to produce chemokines that stimulate MSC recruitment points toward a role for this immune cell population in regulating tissue repair/regeneration. PMID:27052313

  4. Distinct phenotype and function of NK cells in the pancreas of nonobese diabetic mice.

    PubMed

    Brauner, Hanna; Elemans, Marjet; Lemos, Sara; Broberger, Christian; Holmberg, Dan; Flodström-Tullberg, Malin; Kärre, Klas; Höglund, Petter

    2010-03-01

    Little is known about target organ-infiltrating NK cells in type 1 diabetes and other autoimmune diseases. In this study, we identified NK cells with a unique phenotype in the pancreas of NOD mice. Pancreatic NK cells, localized to the endocrine and exocrine parts, were present before T cells during disease development and did not require T cells for their infiltration. Furthermore, NK cells, or NK cell precursors, from the spleen could traffic to the pancreas, where they displayed the pancreatic phenotype. Pancreatic NK cells from other mouse strains shared phenotypic characteristics with pancreatic NK cells from NOD mice, but displayed less surface killer cell lectin-like receptor G1, a marker for mature NK cells that have undergone proliferation, and also did not proliferate to the same extent. A subset of NOD mouse pancreatic NK cells produced IFN-gamma spontaneously, suggesting ongoing effector responses. However, most NOD mouse pancreatic NK cells were hyporesponsive compared with spleen NK cells, as reflected by diminished cytokine secretion and a lower capacity to degranulate. Interestingly, such hyporesponsiveness was not seen in pancreatic NK cells from the nonautoimmune strain C57BL/6, suggesting that this feature is not a general property of pancreatic NK cells. Based on our data, we propose that NK cells are sentinel cells in a normal pancreas. We further speculate that during inflammation, pancreatic NK cells initially mediate proinflammatory effector functions, potentially contributing to organ-specific autoimmunity, but later become hyporesponsive because of exhaustion or regulation.

  5. Effects of cryopreservation on effector cells for antibody dependent cell-mediated cytotoxicity (ADCC) and natural killer (NK) cell activity in (51)Cr-release and CD107a assays.

    PubMed

    Mata, Mariana M; Mahmood, Fareeha; Sowell, Ryan T; Baum, Linda L

    2014-04-01

    Freshly isolated PBMC are broadly used as effector cells in functional assays that evaluate antibody-dependent cell mediated cytotoxicity (ADCC) and NK activity; however, they introduce natural-individual donor-to-donor variability. Cryopreserved PBMC provide a more consistent source of effectors than fresh cells in cytotoxicity assays. Our objective was to determine the effects of cryopreservation of effector PBMC on cell frequency, and on the magnitude and specificity of ADCC and NK activity. Fresh, frozen/overnight rested and frozen/not rested PBMC were used as effector cells in (51)Cr-release and CD107a degranulation assays. Frozen/overnight rested PBMC had higher ADCC and NK activity in both assays when compared to fresh PBMC; however, when using frozen/not rested PBMC, ADCC and NK activities were significantly lower than fresh PBMC. Background CD107a degranulation in the absence of target cell stimulation was greater in PBMC that were frozen/not rested when compared to fresh PBMC or PBMC that were frozen overnight and rested. The percentages of CD16(+)CD56(dim) NK cells and CD14(+) monocytes were lower in PBMC that were frozen and rested overnight than in fresh PBMC. CD16 expression on CD56(dim) NK cells was similar for all PBMC treatments. PBMC that were frozen and rested overnight were comparable to fresh PBMC effectors. PBMC that were frozen and used immediately when evaluating ADCC or NK activity using either a (51)Cr-release assay or a CD107a degranulation assay had the lowest activity. Clinical studies of antibodies that mediate ADCC would benefit from using effector cells that have been frozen, thawed and rested overnight prior to assay.

  6. IκBζ augments IL-12- and IL-18-mediated IFN-γ production in human NK cells.

    PubMed

    Kannan, Yashaswini; Yu, Jianhua; Raices, Raquel M; Seshadri, Sudarshan; Wei, Min; Caligiuri, Michael A; Wewers, Mark D

    2011-03-10

    Interferon-γ (IFN-γ) production by natural killer (NK) cells and cytotoxic lymphocytes is a key component of innate and adaptive immune responses. Because inhibitor of κB-ζ (IκBζ), a Toll-like receptor (TLR)/interleukin-1 receptor (IL-1R) inducible transcription factor, regulates IFN-γ production in KG-1 cells, we tested IκBζ's role in the classic lymphocyte pathway of IL-12/IL-18-induced IFN-γ. Upon stimulation with IL-12/IL-18, monocyte-depleted human peripheral blood lymphocytes expressed the 79-kDa form of IκBζ and released IFN-γ. CD56(+) NK cells were shown to be the IκBζ-producing lymphocyte subpopulation, which also released abundant IFN-γ in response to IL-12/IL-18. Importantly, IκBζ was undetectable in CD56(-) lymphocytes where IFN-γ release was 10-fold lower. In addition, small interfering RNA knockdown of IκBζ suppressed IFN-γ expression in CD56(+) cells. The association of IκBζ with the IFN-γ promoter was documented by chromatin immunoprecipitation. IFN-γ promoter activity from IκBζ overexpression was confirmed by luciferase reporter assay. Finally, IκBζ coprecipitated with p65 and p50 NF-κB in NK cells in response to IL-12/IL-18, suggesting that IκBζ's effects on IFN-γ promoter activity are coregulated by NF-κB. These results suggest that IκBζ functions as an important regulator of IFN-γ in human NK cells, further expanding the class of IκBζ-modulated genes.

  7. HIV-Specific Antibody-Dependent Cellular Cytotoxicity (ADCC) -Mediating Antibodies Decline while NK Cell Function Increases during Antiretroviral Therapy (ART).

    PubMed

    Jensen, Sanne Skov; Fomsgaard, Anders; Borggren, Marie; Tingstedt, Jeanette Linnea; Gerstoft, Jan; Kronborg, Gitte; Rasmussen, Line Dahlerup; Pedersen, Court; Karlsson, Ingrid

    2015-01-01

    Understanding alterations in HIV-specific immune responses during antiretroviral therapy (ART), such as antibody-dependent cellular cytotoxicity (ADCC), is important in the development of novel strategies to control HIV-1 infection. This study included 53 HIV-1 positive individuals. We evaluated the ability of effector cells and antibodies to mediate ADCC separately and in combination using the ADCC-PanToxiLux assay. The ability of the peripheral blood mononuclear cells (PBMCs) to mediate ADCC was significantly higher in individuals who had been treated with ART before seroconversion, compared to the individuals initiating ART at a low CD4+ T cell count (<350 cells/μl blood) and the ART-naïve individuals. The frequency of CD16 expressing natural killer (NK) cells correlated with both the duration of ART and Granzyme B (GzB) activity. In contrast, the plasma titer of antibodies mediating ADCC declined during ART. These findings suggest improved cytotoxic function of the NK cells if initiating ART early during infection, while the levels of ADCC mediating antibodies declined during ART.

  8. Signalling through NK1.1 triggers NK cells to die but induces NK T cells to produce interleukin-4.

    PubMed Central

    Asea, A; Stein-Streilein, J

    1998-01-01

    In vivo inoculation of specific antibody is an accepted protocol for elimination of specific cell populations. Except for anti-CD3 and anti-CD4, it is not known if the depleted cells are eliminated by signalling through the target molecule or through a more non-specific mechanism. C57BL/6 mice were inoculated with anti-natural killer (NK1.1) monoclonal antibody (mAb). Thereafter spleen cells were harvested, stained for both surface and intracellular markers, and analysed by flow cytometry. As early as 2 hr post inoculation, NK cells were signalled to become apoptotic while signalling through the NK1.1 molecule activated NK1.1+ T-cell receptor (TCR)+ (NK T) cells to increase in number, and produce interleukin-4 (IL-4). Anti NK1.1 mAb was less efficient at signalling apoptosis in NK cells when NK T-cell deficient [beta 2-microglobulin beta 2m-deficient] mice were used compared with wild type mice. Efficient apoptotic signalling was restored when beta 2m-deficient mice were reconstituted with NK T cells. NK-specific antibody best signals the apoptotic process in susceptible NK cells when resistant NK T cells are present, activated, and secrete IL-4. Images Figure 4 PMID:9616382

  9. Targeting Stat3 induces senescence in tumor cells and elicits prophylactic and therapeutic immune responses against breast cancer growth mediated by NK cells and CD4+ T cells.

    PubMed

    Tkach, Mercedes; Coria, Lorena; Rosemblit, Cinthia; Rivas, Martín A; Proietti, Cecilia J; Díaz Flaqué, María Celeste; Beguelin, Wendy; Frahm, Isabel; Charreau, Eduardo H; Cassataro, Juliana; Elizalde, Patricia V; Schillaci, Roxana

    2012-08-01

    Aberrant Stat3 activation and signaling contribute to malignant transformation by promoting cell cycle progression, inhibiting apoptosis, and mediating tumor immune evasion. Stat3 inhibition in tumor cells induces the expression of chemokines and proinflammatory cytokines, so we proposed to apply Stat3-inhibited breast cancer cells as a source of immunogens to induce an antitumor immune response. Studies were performed in two murine breast cancer models in which Stat3 is activated: progestin-dependent C4HD cells and 4T1 cells. We immunized BALB/c mice with irradiated cancer cells previously transfected with a dominant-negative Stat3 vector (Stat3Y705F) in either a prophylactic or a therapeutic manner. Prophylactic administration of breast cancer cells transfected with Stat3Y705F (Stat3Y705F-breast cancer cells) inhibited primary tumor growth compared with administration of empty vector-transfected cells in both models. In the 4T1 model, 50% of the challenged mice were tumor free, and the incidence of metastasis decreased by 90%. In vivo assays of C4HD tumors showed that the antitumor immune response involves the participation of CD4(+) T cells and cytotoxic NK cells. Therapeutic immunization with Stat3Y705F-breast cancer cells inhibited tumor growth, promoted tumor cell differentiation, and decreased metastasis. Furthermore, inhibition of Stat3 activation in breast cancer cells induced cellular senescence, contributing to their immunogenic phenotype. In this work, we provide preclinical proof of concept that ablating Stat3 signaling in breast cancer cells results in an effective immunotherapy against breast cancer growth and metastasis. Moreover, our findings showing that Stat3 inactivation results in induction of a cellular senescence program disclose a potential mechanism for immunotherapy research.

  10. NK cell-mediated antibody-dependent cellular cytotoxicity is enhanced by tamoxifen in HER2/neu non-amplified, but not HER2/neu-amplified, breast cancer cells.

    PubMed

    Richards, John O; Albers, Alex J; Smith, Thomas S; Tjoe, Judy A

    2016-11-01

    Tumor-targeting antibodies have been successful in the treatment of various types of cancers. Antibodies engage the immune system with their Fc, stimulating immune cell effector function. In the clinic, FcγRIIIa polymorphisms with higher affinity for the Fc of antibodies were shown to improve response rates and overall survival. Efforts have been made to modify the Fc to enhance affinity to Fc receptors and thereby improve effector function. An alternative for improving immune effector function may be to increase the level of tumor antigen expression. In this study, tamoxifen was used to increase HER2/neu protein level to determine whether increased tumor antigen expression could enhance NK cell-mediated antibody-dependent cytotoxicity (ADCC). Tamoxifen was found to increase HER2/neu 1.5-fold to threefold in breast cancer cell lines that were HER2/neu non-amplified. Using flow cytometry to simultaneously evaluate NK cell degranulation and tumor cell death, the increase in HER2/neu enhanced NK cell-mediated ADCC. However, in cells that had HER2/neu gene amplification and estrogen receptor expression, tamoxifen elevated HER2/neu but failed to improve NK cell function. The quantity of HER2/neu on the tumor cell surface was approximately double that of the number of Fc receptors found on NK cells. This appears to reflect a ceiling at which increasing antigen expression fails to improve NK cell effector function. This has clinical implications as trying to increase antigen expression to enhance NK cell function may be useful for patients with antigen-low tumors, but not in those whose tumors have gene amplification or high levels of antigen expression.

  11. Human NK cells: From surface receptors to clinical applications.

    PubMed

    Moretta, Lorenzo; Pietra, Gabriella; Vacca, Paola; Pende, Daniela; Moretta, Francesca; Bertaina, Alice; Mingari, Maria Cristina; Locatelli, Franco; Moretta, Alessandro

    2016-10-01

    Natural killer (NK) cells play a major role in innate defenses against pathogens, primarily viruses, and are also thought to be part of the immunosurveillance against tumors. They express an array of surface receptors that mediate NK cell function. The human leukocytes antigen (HLA) class I-specific inhibitory receptors allow NK cells to detect and kill cells that have lost or under-express HLA class I antigens, a typical feature of tumor or virally infected cells. However, NK cell activation and induction of cytolytic activity and cytokine production depends on another important checkpoint, namely the expression on target cells of ligands recognized by activating NK receptors. Despite their potent cytolytic activity, NK cells frequently fail to eliminate tumors. This is due to mechanisms of tumor escape, determined by the tumor cells themselves or by tumor-associated cells (i.e. the tumor microenvironment) via the release of soluble suppressive factors or the induction of inhibitory loops involving induction of regulatory T cells, M2-polarized macrophages and myeloid-derived suppressor cells. The most important clinical application involving NK cells is the cure of high-risk leukemias in the haplo-identical hematopoietic stem cell transplant (HSCT) setting. NK cells originated from hematopoietic stem cells (HSC) of HLA-haploidentical donors may express Killer Immunoglobulin-like receptors (KIRs) that are mismatched with the HLA class I alleles of the recipient. This allows NK cells to kill leukemia blasts residual after the conditioning regimen, while sparing normal cells (that do not express ligands for activating NK receptors). More recent approaches based on the specific removal of TCR α/β(+) T cells and of CD19(+) B cells, allow the infusion, together with CD34(+) HSC, of mature KIR(+) NK cells and of TCR γ/δ(+) T cells, both characterized by a potent anti-leukemia activity. This greatly reduces the time interval necessary to obtain alloreactive, KIR(+) NK

  12. Macrophage and NK-mediated killing of precursor-B acute lymphoblastic leukemia cells targeted with a-fucosylated anti-CD19 humanized antibodies.

    PubMed

    Matlawska-Wasowska, K; Ward, E; Stevens, S; Wang, Y; Herbst, R; Winter, S S; Wilson, B S

    2013-06-01

    This work reports the tumoricidal effects of a novel investigational humanized anti-CD19 monoclonal antibody (Medi-551). An a-fucosylated antibody with increased affinity for human FcγRIIIA, Medi-551 is shown to mediate both antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP). Medi-551/CD19 complexes internalize slowly (>5 h) and thus remain accessible to effector cells for prolonged periods. We evaluated in vitro ADCC and ADCP activities of primary human natural killer (NK) cells and macrophages against precursor-B (pre-B) acute lymphoblastic leukemia (ALL) cell lines and pediatric patient blasts. Fluorescent imaging studies document immunological synapses formed between anti-CD19-bound target leukemia cells and effector cells and capture the kinetics of both NK-mediated killing and macrophage phagocytosis. Genetic polymorphisms in FcγRIIIA-158F/V modulate in vitro activities of effector cells, with FcγRIIIA-158V homozygotes or heterozygotes showing the strongest activity. Medi-551 treatment of severe combined immunodeficiency (SCID) mice engrafted with human pre-B cells led to prolonged animal survival and markedly reduced disease burden in blood, liver and bone marrow. These data show that anti-CD19 antibodies effectively recruit immune cells to pre-B ALL cells and support a move forward to early phase trials in this disease.

  13. NK Cell Subtypes as Regulators of Autoimmune Liver Disease

    PubMed Central

    2016-01-01

    As major components of innate immunity, NK cells not only exert cell-mediated cytotoxicity to destroy tumors or infected cells, but also act to regulate the functions of other cells in the immune system by secreting cytokines and chemokines. Thus, NK cells provide surveillance in the early defense against viruses, intracellular bacteria, and cancer cells. However, the effecter function of NK cells must be exquisitely controlled to prevent inadvertent attack against normal “self” cells. In an organ such as the liver, where the distinction between immunotolerance and immune defense against routinely processed pathogens is critical, the plethora of NK cells has a unique role in the maintenance of homeostasis. Once self-tolerance is broken, autoimmune liver disease resulted. NK cells act as a “two-edged weapon” and even play opposite roles with both regulatory and inducer activities in the hepatic environment. That is, NK cells act not only to produce inflammatory cytokines and chemokines, but also to alter the proliferation and activation of associated lymphocytes. However, the precise regulatory mechanisms at work in autoimmune liver diseases remain to be identified. In this review, we focus on recent research with NK cells and their potential role in the development of autoimmune liver disease. PMID:27462349

  14. NK Cells: Uncertain Allies against Malaria

    PubMed Central

    Wolf, Asia-Sophia; Sherratt, Samuel; Riley, Eleanor M.

    2017-01-01

    Until recently, studies of natural killer (NK) cells in infection have focused almost entirely on their role in viral infections. However, there is an increasing awareness of the potential for NK cells to contribute to the control of a wider range of pathogens, including intracellular parasites such as Plasmodium spp. Given the high prevalence of parasitic diseases in the developing world and the devastating effects these pathogens have on large numbers of vulnerable people, investigating interactions between NK cells and parasitized host cells presents the opportunity to reveal novel immunological mechanisms with the potential to aid efforts to eradicate these diseases. The capacity of NK cells to produce inflammatory cytokines early after malaria infection, as well as a possible role in direct cytotoxic killing of malaria-infected cells, suggests a beneficial impact of NK cells in this disease. However, NK cells may also contribute to overproduction of pro-inflammatory cytokines and the consequent immunopathology. As comparatively little is known about the role of NK cells later in the course of infection, and growing evidence suggests that heterogeneity in NK cell responses to malaria may be influenced by KIR/HLA interactions, a better understanding of the mechanisms by which NK cells might directly interact with parasitized cells may reveal a new role for these cells in the course of malaria infection. PMID:28337195

  15. NK Cells: Uncertain Allies against Malaria.

    PubMed

    Wolf, Asia-Sophia; Sherratt, Samuel; Riley, Eleanor M

    2017-01-01

    Until recently, studies of natural killer (NK) cells in infection have focused almost entirely on their role in viral infections. However, there is an increasing awareness of the potential for NK cells to contribute to the control of a wider range of pathogens, including intracellular parasites such as Plasmodium spp. Given the high prevalence of parasitic diseases in the developing world and the devastating effects these pathogens have on large numbers of vulnerable people, investigating interactions between NK cells and parasitized host cells presents the opportunity to reveal novel immunological mechanisms with the potential to aid efforts to eradicate these diseases. The capacity of NK cells to produce inflammatory cytokines early after malaria infection, as well as a possible role in direct cytotoxic killing of malaria-infected cells, suggests a beneficial impact of NK cells in this disease. However, NK cells may also contribute to overproduction of pro-inflammatory cytokines and the consequent immunopathology. As comparatively little is known about the role of NK cells later in the course of infection, and growing evidence suggests that heterogeneity in NK cell responses to malaria may be influenced by KIR/HLA interactions, a better understanding of the mechanisms by which NK cells might directly interact with parasitized cells may reveal a new role for these cells in the course of malaria infection.

  16. Murine thymic NK cells are distinct from ILC1s and have unique transcription factor requirements.

    PubMed

    Gabrielli, Sara; Sun, Mengxi; Bell, April; Zook, Erin C; de Pooter, Renee F; Zamai, Loris; Kee, Barbara L

    2017-03-09

    Group 1 innate lymphoid cells include natural killer (NK) cells and ILC1s, which mediate the response to intracellular pathogens. Thymic NK (tNK) cells were described with hybrid features of immature NK cells and ILC1 but whether these cells are related to NK cells or ILC1 has not been fully investigated. We report that murine tNK cells expressed the NK-cell associated transcription factor EOMES and developed independent of the essential ILC1 factor TBET, confirming their placement within the NK lineage. Moreover, tNK cells resemble NK cells rather than ILC1 in their requirements for the E protein transcription factor inhibitor ID2. We provide further insight into the mechanisms governing tNK-cell development by showing that the transcription factor ETS1 prevented tNK cell acquisition of the conventional NK-cell maturation markers CD11b and KLRG1. Our data reveal few ILC1 in the thymus and clarify the identity and developmental requirements of tNK cells. This article is protected by copyright. All rights reserved.

  17. NK-CD11c+ Cell Crosstalk in Diabetes Enhances IL-6-Mediated Inflammation during Mycobacterium tuberculosis Infection.

    PubMed

    Cheekatla, Satyanarayana Swamy; Tripathi, Deepak; Venkatasubramanian, Sambasivan; Nathella, Pavan Kumar; Paidipally, Padmaja; Ishibashi, Munenori; Welch, Elwyn; Tvinnereim, Amy R; Ikebe, Mitsuo; Valluri, Vijaya Lakshmi; Babu, Subash; Kornfeld, Hardy; Vankayalapati, Ramakrishna

    2016-10-01

    In this study, we developed a mouse model of type 2 diabetes mellitus (T2DM) using streptozotocin and nicotinamide and identified factors that increase susceptibility of T2DM mice to infection by Mycobacterium tuberculosis (Mtb). All Mtb-infected T2DM mice and 40% of uninfected T2DM mice died within 10 months, whereas all control mice survived. In Mtb-infected mice, T2DM increased the bacterial burden and pro- and anti-inflammatory cytokine and chemokine production in the lungs relative to those in uninfected T2DM mice and infected control mice. Levels of IL-6 also increased. Anti-IL-6 monoclonal antibody treatment of Mtb-infected acute- and chronic-T2DM mice increased survival (to 100%) and reduced pro- and anti-inflammatory cytokine expression. CD11c+ cells were the major source of IL-6 in Mtb-infected T2DM mice. Pulmonary natural killer (NK) cells in Mtb-infected T2DM mice further increased IL-6 production by autologous CD11c+ cells through their activating receptors. Anti-NK1.1 antibody treatment of Mtb-infected acute-T2DM mice increased survival and reduced pro- and anti-inflammatory cytokine expression. Furthermore, IL-6 increased inflammatory cytokine production by T lymphocytes in pulmonary tuberculosis patients with T2DM. Overall, the results suggest that NK-CD11c+ cell interactions increase IL-6 production, which in turn drives the pathological immune response and mortality associated with Mtb infection in diabetic mice.

  18. NK-CD11c+ Cell Crosstalk in Diabetes Enhances IL-6-Mediated Inflammation during Mycobacterium tuberculosis Infection

    PubMed Central

    Cheekatla, Satyanarayana Swamy; Tripathi, Deepak; Venkatasubramanian, Sambasivan; Nathella, Pavan Kumar; Paidipally, Padmaja; Ishibashi, Munenori; Welch, Elwyn; Tvinnereim, Amy R.; Ikebe, Mitsuo; Valluri, Vijaya Lakshmi; Babu, Subash; Kornfeld, Hardy; Vankayalapati, Ramakrishna

    2016-01-01

    In this study, we developed a mouse model of type 2 diabetes mellitus (T2DM) using streptozotocin and nicotinamide and identified factors that increase susceptibility of T2DM mice to infection by Mycobacterium tuberculosis (Mtb). All Mtb-infected T2DM mice and 40% of uninfected T2DM mice died within 10 months, whereas all control mice survived. In Mtb-infected mice, T2DM increased the bacterial burden and pro- and anti-inflammatory cytokine and chemokine production in the lungs relative to those in uninfected T2DM mice and infected control mice. Levels of IL-6 also increased. Anti-IL-6 monoclonal antibody treatment of Mtb-infected acute- and chronic-T2DM mice increased survival (to 100%) and reduced pro- and anti-inflammatory cytokine expression. CD11c+ cells were the major source of IL-6 in Mtb-infected T2DM mice. Pulmonary natural killer (NK) cells in Mtb-infected T2DM mice further increased IL-6 production by autologous CD11c+ cells through their activating receptors. Anti-NK1.1 antibody treatment of Mtb-infected acute-T2DM mice increased survival and reduced pro- and anti-inflammatory cytokine expression. Furthermore, IL-6 increased inflammatory cytokine production by T lymphocytes in pulmonary tuberculosis patients with T2DM. Overall, the results suggest that NK-CD11c+ cell interactions increase IL-6 production, which in turn drives the pathological immune response and mortality associated with Mtb infection in diabetic mice. PMID:27783671

  19. Altered distribution of mucosal NK cells during HIV infection

    PubMed Central

    Sips, Magdalena; Sciaranghella, Gaia; Diefenbach, Thomas; Dugast, Anne-Sophie; Berger, Christoph T.; Liu, Qingquan; Kwon, Douglas; Ghebremichael, Musie; Estes, Jacob D.; Carrington, Mary; Martin, Jeffrey N.; Deeks, Steven G.; Hunt, Peter W.; Alter, Galit

    2013-01-01

    The human gut mucosa is a major site of HIV infection and infection-associated pathogenesis. Increasing evidence shows that natural killer (NK) cells play an important role in control of HIV infection but the mechanism(s) by which they mediate antiviral activity in the gut is unclear. Here we show two distinct subsets of NK cells exist in the gut, one localized to intraepithelial spaces (IEL) and the other to the lamina propria (LP). The frequency of both subsets of NK cells was reduced in chronic infection, whereas IEL NK cells remained stable in spontaneous controllers with protective KIR/HLA genotypes. Both IEL and LP NK cells were significantly expanded in immunologic non-responsive (INR) patients, who incompletely recovered CD4+ T cells on HAART. These data suggest that both IEL and LP NK cells may expand in the gut in an effort to compensate for compromised CD4+ T cell recovery, but that only IEL NK cells may be involved in providing durable control of HIV in the gut, PMID:21993602

  20. Contrasting Effects of the Cytotoxic Anticancer Drug Gemcitabine and the EGFR Tyrosine Kinase Inhibitor Gefitinib on NK Cell-Mediated Cytotoxicity via Regulation of NKG2D Ligand in Non-Small-Cell Lung Cancer Cells

    PubMed Central

    Okita, Riki; Wolf, Diana; Yasuda, Koichiro; Maeda, Ai; Yukawa, Takuro; Saisho, Shinsuke; Shimizu, Katsuhiko; Yamaguchi, Yoshiyuki; Oka, Mikio; Nakayama, Eiichi; Lundqvist, Andreas; Kiessling, Rolf; Seliger, Barbara; Nakata, Masao

    2015-01-01

    Introduction Several cytotoxic anticancer drugs inhibit DNA replication and/or mitosis, while EGFR tyrosine kinase inhibitors inactivate EGFR signalling in cancer cell. Both types of anticancer drugs improve the overall survival of the patients with non-small-cell lung cancer (NSCLC), although tumors often become refractory to this treatment. Despite several mechanisms by which the tumors become resistant having been described the effect of these compounds on anti-tumor immunity remains largely unknown. Methods This study examines the effect of the cytotoxic drug Gemcitabine and the EGFR tyrosine kinase inhibitor Gefitinib on the expression of NK group 2 member D (NKG2D) ligands as well as the sensitivity of NSCLC cells to the NK-mediated lysis. Results We demonstrate that Gemcitabine treatment leads to an enhanced expression, while Gefitinib downregulated the expression of molecules that act as key ligands for the activating receptor NKG2D and promote NK cell-mediated recognition and cytolysis. Gemcitabine activated ATM and ATM- and Rad-3-related protein kinase (ATR) pathways. The Gemcitabine-induced phosphorylation of ATM as well as the upregulation of the NKG2D ligand expression could be blocked by an ATM-ATR inhibitor. In contrast, Gefitinib attenuated NKG2D ligand expression. Silencing EGFR using siRNA or addition of the PI3K inhibitor resulted in downregulation of NKG2D ligands. The observations suggest that the EGFR/PI3K pathway also regulates the expression of NKG2D ligands. Additionally, we showed that both ATM-ATR and EGFR regulate MICA/B via miR20a. Conclusion In keeping with the effect on NKG2D expression, Gemcitabine enhanced NK cell-mediated cytotoxicity while Gefitinib attenuated NK cell killing in NSCLC cells. PMID:26439264

  1. Histone Deacetylase Inhibitors Enhance CD4 T Cell Susceptibility to NK Cell Killing but Reduce NK Cell Function.

    PubMed

    Pace, Matthew; Williams, James; Kurioka, Ayako; Gerry, Andrew B; Jakobsen, Bent; Klenerman, Paul; Nwokolo, Nneka; Fox, Julie; Fidler, Sarah; Frater, John

    2016-08-01

    In the search for a cure for HIV-1 infection, histone deacetylase inhibitors (HDACi) are being investigated as activators of latently infected CD4 T cells to promote their targeting by cytotoxic T-lymphocytes (CTL). However, HDACi may also inhibit CTL function, suggesting different immunotherapy approaches may need to be explored. Here, we study the impact of different HDACi on both Natural Killer (NK) and CTL targeting of HIV-1 infected cells. We found HDACi down-regulated HLA class I expression independently of HIV-1 Nef which, without significantly compromising CTL function, led to enhanced targeting by NK cells. HDACi-treated HIV-1-infected CD4 T cells were also more effectively cleared than untreated controls during NK co-culture. However, HDACi impaired NK function, reducing degranulation and killing capacity. Depending on the HDACi and dose, this impairment could counteract the benefit gained by treating infected target cells. These data suggest that following HDACi-induced HLA class I down-regulation NK cells kill HIV-1-infected cells, although HDACi-mediated NK cell inhibition may negate this effect. Our data emphasize the importance of studying the effects of potential interventions on both targets and effectors.

  2. No monkey business: why studying NK cells in non-human primates pays off.

    PubMed

    Hong, Henoch S; Rajakumar, Premeela A; Billingsley, James M; Reeves, R Keith; Johnson, R Paul

    2013-01-01

    Human NK (hNK) cells play a key role in mediating host immune responses against various infectious diseases. For practical reasons, the majority of the data on hNK cells has been generated using peripheral blood lymphocytes. In contrast, our knowledge of NK cells in human tissues is limited, and not much is known about developmental pathways of hNK cell subpopulations in vivo. Although research in mice has elucidated a number of fundamental features of NK cell biology, mouse, and hNK cells significantly differ in their subpopulations, functions, and receptor repertoires. Thus, there is a need for a model that is more closely related to humans and yet allows experimental manipulations. Non-human primate models offer numerous opportunities for the study of NK cells, including the study of the role of NK cells after solid organ and stem cell transplantation, as well as in acute viral infection. Macaque NK cells can be depleted in vivo or adoptively transferred in an autologous system. All of these studies are either difficult or unethical to carry out in humans. Here we highlight recent advances in rhesus NK cell research and their parallels in humans. Using high-throughput transcriptional profiling, we demonstrate that the human CD56(bright) and CD56(dim) NK cell subsets have phenotypically and functionally analogous counterparts in rhesus macaques. Thus, the use of non-human primate models offers the potential to substantially advance hNK cell research.

  3. Mouse host unlicensed NK cells promote donor allogeneic bone marrow engraftment.

    PubMed

    Alvarez, Maite; Sun, Kai; Murphy, William J

    2016-03-03

    Natural killer (NK) cells exist as subsets based on expression of inhibitory receptors that recognize major histocompatibility complex I (MHCI) molecules. NK cell subsets bearing MHCI binding receptors for self-MHCI have been termed as "licensed" and exhibit a higher ability to respond to stimuli. In the context of bone marrow transplantation (BMT), host licensed-NK (L-NK) cells have also been demonstrated to be responsible for the acute rejection of allogeneic and MHCI-deficient BM cells (BMCs) in mice after lethal irradiation. However, the role of recipient unlicensed-NK (U-NK) cells has not been well established with regard to allogeneic BMC resistance. After NK cell stimulation, the prior depletion of host L-NK cells resulted in a marked increase of donor engraftment compared with the untreated group. Surprisingly, this increased donor engraftment was reduced after total host NK cell depletion, indicating that U-NK cells can actually promote donor allogeneic BMC engraftment. Furthermore, direct coculture of U-NK cells with allogeneic but not syngeneic BMCs resulted in increased colony-forming unit cell growth in vitro, which was at least partially mediated by granulocyte macrophage colony-stimulating factor (GM-CSF) production. These data demonstrate that host NK cell subsets exert markedly different roles in allogeneic BMC engraftment where host L- and U-NK cells reject or promote donor allogeneic BMC engraftment, respectively.

  4. HIF-2α/ITPR1 axis: A new saboteur of NK-mediated lysis

    PubMed Central

    Messai, Yosra; Noman, Muhammad Zaeem; Hasmim, Meriem; Escudier, Bernard; Chouaib, Salem

    2015-01-01

    We recently investigated the role of von Hippel-Lindau (VHL) mutation and the subsequent induction of hypoxia-inducible factor 2α (HIF-2α) in the regulation of renal cell carcinoma (RCC) susceptibility to natural killer (NK) cell-mediated killing. We demonstrated that the resistance of VHL-mutated RCC cell line 786-0 to NK-mediated lysis requires HIF-2α and ITPR1, a direct novel target of HIF-2α, through the activation of autophagy in target cells by NK-derived signals. PMID:25949883

  5. Homotypic NK cell-to-cell communication controls cytokine responsiveness of innate immune NK cells.

    PubMed

    Kim, Tae-Jin; Kim, Miju; Kim, Hye Mi; Lim, Seon Ah; Kim, Eun-Ok; Kim, Kwanghee; Song, Kwang Hoon; Kim, Jiyoung; Kumar, Vinay; Yee, Cassian; Doh, Junsang; Lee, Kyung-Mi

    2014-12-05

    While stationary organ cells are in continuous contact with neighboring cells, immune cells circulate throughout the body without an apparent requirement for cell-cell contact to persist in vivo. This study challenges current convention by demonstrating, both in vitro and in vivo, that innate immune NK cells can engage in homotypic NK-to-NK cell interactions for optimal survival, activation, and proliferation. Using a specialized cell-laden microwell approach, we discover that NK cells experiencing constant NK-to-NK contact exhibit a synergistic increase in activation status, cell proliferation, and anti-tumor function in response to IL-2 or IL-15. This effect is dependent on 2B4/CD48 ligation and an active cytoskeleton, resulting in amplification of IL-2 receptor signaling, enhanced CD122/CD132 colocalization, CD25 upregulation, and Stat3 activation. Conversely, 'orphan' NK cells demonstrate no such synergy and fail to persist. Therefore, our data uncover the existence of homotypic cell-to-cell communication among mobile innate lymphocytes, which promotes functional synergy within the cytokine-rich microenvironment.

  6. Tim-3 Is Upregulated in NK Cells during Early Pregnancy and Inhibits NK Cytotoxicity toward Trophoblast in Galectin-9 Dependent Pathway

    PubMed Central

    Sun, Jintang; Yang, Meixiang; Ban, Yanli; Gao, Wenjuan; Song, Bingfeng; Wang, Yang; Zhang, Yun; Shao, Qianqian; Kong, Beihua; Qu, Xun

    2016-01-01

    NK cells accumulate at the maternal-fetal interface (MFI) and play essential roles in maintaining immune tolerance during pregnancy. The mechanisms that facilitate NK cells tolerance to fetal tissue are largely unknown. T cell Ig and mucin domain-containing protein 3 (Tim-3) is a newly defined molecule with essential immunological function in many physiological and pathological processes. Recent study showed that Tim-3 was involved in the regulation of immune tolerance at MFI. However, whether Tim-3 regulates NK cells cytotoxicity toward trophoblasts is unclear. Here, we showed Tim-3 was mainly expressed by decidual NK cells (dNK) and Tim-3 level in dNK was higher than peripheral NK cells (pNK). Tim-3+ dNK expressed more levels of mature markers CD94 and CD69 than Tim-3- dNK cells and blocking Tim-3 significantly inhibited dNK IFN-γ and TNF-α secretion. Furthermore, we found TGF-β1 may contribute to such up-regulation of Tim-3 in NK cells. Interestingly, blocking Tim-3 enhanced NK cytotoxicity toward trophoblast cell line HTR-8 but not K562. We found HTR-8 expressed Tim-3 ligand Galectin-9, in contrast K562 did not. Small interfering RNA-mediated silencing of Galectin-9 expression enhanced NK cytotoxicity toward HTR-8. We further showed Tim-3/Galecin-9 inhibited NK cytotoxicity toward trophoblast partially via impairing the degranulation process. In addition, clinical data showed that abnormal Tim-3 level on pNK might be associated with recurrent spontaneous abortion (RSA). Thus, our data demonstrate Tim-3/Galectin-9 pathway maintains local tolerance by suppressing NK cytotoxicity toward trophoblasts which may represent a new immunologic tolerance mechanism at MFI. PMID:26789128

  7. Tim-3 Is Upregulated in NK Cells during Early Pregnancy and Inhibits NK Cytotoxicity toward Trophoblast in Galectin-9 Dependent Pathway.

    PubMed

    Sun, Jintang; Yang, Meixiang; Ban, Yanli; Gao, Wenjuan; Song, Bingfeng; Wang, Yang; Zhang, Yun; Shao, Qianqian; Kong, Beihua; Qu, Xun

    2016-01-01

    NK cells accumulate at the maternal-fetal interface (MFI) and play essential roles in maintaining immune tolerance during pregnancy. The mechanisms that facilitate NK cells tolerance to fetal tissue are largely unknown. T cell Ig and mucin domain-containing protein 3 (Tim-3) is a newly defined molecule with essential immunological function in many physiological and pathological processes. Recent study showed that Tim-3 was involved in the regulation of immune tolerance at MFI. However, whether Tim-3 regulates NK cells cytotoxicity toward trophoblasts is unclear. Here, we showed Tim-3 was mainly expressed by decidual NK cells (dNK) and Tim-3 level in dNK was higher than peripheral NK cells (pNK). Tim-3(+) dNK expressed more levels of mature markers CD94 and CD69 than Tim-3- dNK cells and blocking Tim-3 significantly inhibited dNK IFN-γ and TNF-α secretion. Furthermore, we found TGF-β1 may contribute to such up-regulation of Tim-3 in NK cells. Interestingly, blocking Tim-3 enhanced NK cytotoxicity toward trophoblast cell line HTR-8 but not K562. We found HTR-8 expressed Tim-3 ligand Galectin-9, in contrast K562 did not. Small interfering RNA-mediated silencing of Galectin-9 expression enhanced NK cytotoxicity toward HTR-8. We further showed Tim-3/Galecin-9 inhibited NK cytotoxicity toward trophoblast partially via impairing the degranulation process. In addition, clinical data showed that abnormal Tim-3 level on pNK might be associated with recurrent spontaneous abortion (RSA). Thus, our data demonstrate Tim-3/Galectin-9 pathway maintains local tolerance by suppressing NK cytotoxicity toward trophoblasts which may represent a new immunologic tolerance mechanism at MFI.

  8. Dacarbazine-mediated upregulation of NKG2D ligands on tumor cells activates NK and CD8 T cells and restrains melanoma growth.

    PubMed

    Hervieu, Alice; Rébé, Cédric; Végran, Frédérique; Chalmin, Fanny; Bruchard, Mélanie; Vabres, Pierre; Apetoh, Lionel; Ghiringhelli, François; Mignot, Grégoire

    2013-02-01

    Dacarbazine (DTIC) is a cytotoxic drug widely used for melanoma treatment. However, the putative contribution of anticancer immune responses in the efficacy of DTIC has not been evaluated. By testing how DTIC affects host immune responses to cancer in a mouse model of melanoma, we unexpectedly found that both natural killer (NK) and CD8(+) T cells were indispensable for DTIC therapeutic effect. Although DTIC did not directly affect immune cells, it triggered the upregulation of NKG2D ligands on tumor cells, leading to NK cell activation and IFNγ secretion in mice and humans. NK cell-derived IFNγ subsequently favored upregulation of major histocompatibility complex class I molecules on tumor cells, rendering them sensitive to cytotoxic CD8(+) T cells. Accordingly, DTIC markedly enhanced cytotoxic T lymphocyte antigen 4 inhibition efficacy in vivo in an NK-dependent manner. These results underscore the immunogenic properties of DTIC and provide a rationale to combine DTIC with immunotherapeutic agents that relieve immunosuppression in vivo.

  9. Upregulation of CD54 and downregulation of HLA‑ABC contribute to the novel enhancement of the susceptibility of HL-60 cells to NK cell-mediated cytolysis induced by ATRA plus VPA.

    PubMed

    Zou, Huijuan; Li, Lianlian; Han, Yang; Ma, Ruiping; Liao, Qiong; Tian, Jing; Zhang, Xiaoyu; Ren, Xia; Song, Guanhua; Guo, Qiang; Li, Xia; Ding, Huifang; Jiang, Guosheng

    2017-01-01

    Enhancement of the susceptibility of HL-60 cells to NK cell-mediated cytolysis induced by all-trans-retinoic acid (ATRA) plus valproate (VPA) was evaluated. In addition to the synergistic effect of ATRA plus VPA on HL-60 cells, the optimal concentration of 1 mM VPA plus 0.5 µM ATRA increased the cytotoxic sensitivity of HL-60 cells to NK cells. The expression of the activated receptors NKp30 and NKG2D on NK-92 cells was higher compared with the levels noted for the other receptors, and the expression of NKG2D ligands MICA/B on HL-60 cells was not significantly upregulated in the ATRA plus VPA goup compared with the control. Moreover, it was observed that the ligands of NKp30 on HL-60 cells presented the same variation trend. As to the co-stimulatory and adhesion molecules on NK-92 and their ligands on HL-60 cells post exposure to ATRA and VPA alone or their combination, there was no obvious change in the expression of CD112, CD48 and CD70 on the HL-60 cells. However, the expression of CD54 on HL-60 cells was significantly upregulated. In contrast, the expression of NKG2A ligands HLA-ABC on HL-60 cells was obviously downregulated. In addition, the expression of HLA-E on the HL-60 cells in the group treated with ATRA plus VPA was not significantly increased. In conclusion, the combination of VPA and ATRA not only induced the differentiation of HL-60 cells, but also induced enhancement of the sensitivity of HL-60 cells to NK cells by downregulating the expression of HLA-ABC and upregulating the expression of CD54, but not MICA/MICB. The results provide experimental and theoretical basis for the clinical combination of a low-dose of ATRA plus VPA for the treatment of leukemia.

  10. Natural Killer Cells for Immunotherapy - Advantages of the NK-92 Cell Line over Blood NK Cells.

    PubMed

    Klingemann, Hans; Boissel, Laurent; Toneguzzo, Frances

    2016-01-01

    Natural killer (NK) cells are potent cytotoxic effector cells for cancer therapy and potentially for severe viral infections. However, there are technical challenges to obtain sufficient numbers of functionally active NK cells from a patient's blood since they represent only 10% of the lymphocytes and are often dysfunctional. The alternative is to obtain cells from a healthy donor, which requires depletion of the allogeneic T cells to prevent graft-versus-host reactions. Cytotoxic cell lines have been established from patients with clonal NK-cell lymphoma. Those cells can be expanded in culture in the presence of IL-2. Except for the NK-92 cell line, though, none of the other six known NK cell lines has consistently and reproducibly shown high antitumor cytotoxicity. Only NK-92 cells can easily be genetically manipulated to recognize specific tumor antigens or to augment monoclonal antibody activity through antibody-dependent cellular cytotoxicity. NK-92 is also the only cell line product that has been infused into patients with advanced cancer with clinical benefit and minimal side effects.

  11. Upregulation of thioredoxin-1 in activated human NK cells confers increased tolerance to oxidative stress.

    PubMed

    Mimura, Kousaku; Kua, Ley-Fang; Shimasaki, Noriko; Shiraishi, Kensuke; Nakajima, Shotaro; Siang, Lim Kee; Shabbir, Asim; So, Jimmy; Yong, Wei-Peng; Kono, Koji

    2017-02-21

    Adoptive transfer of immune cells, such as T lymphocytes and NK cells, has potential to control cancer growth. However, this can be counteracted by immune escape mechanisms within the tumor microenvironment, including those mediated by reactive oxygen species (ROS). Here, we determined the levels of anti-oxidant molecules in NK cells and their capacity to overcome ROS-induced immune suppression. We investigated the effect of H2O2 on resting NK cells, IL-2-activated NK cells and NK cells expanded by coculture with the K562 leukemia cell line genetically modified to express membrane-bound IL-15 and 4-1BB ligand (K562-mb15-41BBL). Expression of anti-oxidant and anti-apoptotic genes was evaluated by expression array, and protein levels of anti-oxidant molecules by Western blot. Activated NK cells, IL-2-activated NK cells and NK cells expanded by K562-mb15-41BBL were significantly more resistant to H2O2-induced cell death than resting NK. Thioredoxin-1 (TXN1) and peroxiredoxin-1 (PRDX1) were also up-regulated in activated NK cells. Moreover, H2O2-induced cell death after IL-2 activation was significantly induced in the presence of an anti-TXN1-neutralising antibody. Collectively, these data document that activated NK cells can resist to H2O2-induced cell death by up-regulation of TXN1.

  12. Ionomycin Treatment Renders NK Cells Hyporesponsive

    PubMed Central

    Romera-Cárdenas, Gema; Thomas, L. Michael; Lopez-Cobo, Sheila; García-Cuesta, Eva M.; Long, Eric O.; Reyburn, Hugh T.

    2016-01-01

    Natural killer cells are cytotoxic lymphocytes important in immune responses to cancer and multiple pathogens. However, chronic activation of NK cells can induce a hyporesponsive state. The molecular basis of the mechanisms underlying the generation and maintenance of this hyporesponsive condition are unknown, thus an easy and reproducible mechanism able to induce hyporesponsiveness on human NK cells would be very useful to gain understanding of this process. Human NK cells treated with ionomycin lose their ability to degranulate and secrete IFN-γ in response to a variety of stimuli, but IL-2 stimulation can compensate these defects. Apart from reductions in the expression of CD11a/CD18, no great changes were observed in the activating and inhibitory receptors expressed by these NK cells, however their transcriptional signature is different to that described for other hyporesponsive lymphocytes. PMID:27007115

  13. NK cell-based cancer immunotherapy: from basic biology to clinical application.

    PubMed

    Li, Yang; Yin, Jie; Li, Ting; Huang, Shan; Yan, Han; Leavenworth, JianMei; Wang, Xi

    2015-12-01

    Natural killer (NK) cells, which recognize and kill target cells independent of antigen specificity and major histocompatibility complex (MHC) matching, play pivotal roles in immune defence against tumors. However, tumor cells often acquire the ability to escape NK cell-mediated immune surveillance. Thus, understanding mechanisms underlying regulation of NK cell phenotype and function within the tumor environment is instrumental for designing new approaches to improve the current cell-based immunotherapy. In this review, we elaborate the main biological features and molecular mechanisms of NK cells that pertain to regulation of NK cell-mediated anti-tumor activity. We further overview current clinical approaches regarding NK cell-based cancer therapy, including cytokine infusion, adoptive transfer of autologous or allogeneic NK cells, applications of chimeric antigen receptor (CAR)-expressing NK cells and adoptive transfer of memory-like NK cells. With these promising clinical outcomes and fuller understanding the basic questions raised in this review, we foresee that NK cell-based approaches may hold great potential for future cancer immunotherapy.

  14. NK Cell–Mediated Antitumor Effects of a Folate-Conjugated Immunoglobulin are Enhanced by Cytokines

    PubMed Central

    Kondadasula, SriVidya; Skinner, Cassandra C.; Mundy-Bosse, Bethany L.; Luedke, Eric; Jones, Natalie B.; Mani, Aruna; Roda, Julie; Karpa, Volodymyr; Li, Hong; Li, Jilong; Elavazhagan, Saranya; La Perle, Krista M.; Schmitt, Alessandra C.; Lu, Yanhui; Zhang, Xiaoli; Pan, Xueliang; Mao, Hsaioyin; Davis, Melanie; Jarjoura, David; Butchar, Jonathan P.; Poi, Ming; Phelps, Mitch; Tridandapani, Susheela; Byrd, John C.; Caligiuri, Michael A.; Lee, Robert J.; Carson, William E.

    2016-01-01

    Optimally effective antitumor therapies would not only activate immune effector cells, but engage them at the tumor. Folate-conjugated to immunoglobulin (F-IgG) could direct innate immune cells with Fc receptors to folate receptor–expressing cancer cells. F-IgG bound to human KB and HeLa cells, as well as murine L1210JF, a folate receptor (FR) overexpressing cancer cell line, as determined by flow cytometry. Recognition of F-IgG by NK cell Fc receptors led to phosphorylation of the ERK transcription factor and increased NK cell expression of CD69. Lysis of KB tumor cells by NK cells increased about 5-fold after treatment with F-IgG, an effect synergistically enhanced by treatment with IL2, IL12, IL15, or IL21 (P < 0.001). F-IgG also enhanced the lysis of chronic lymphocytic leukemia cells by autologous NK cells. NK cells significantly increased production of IFNγ, MIP-1α, and RANTES in response to F-IgG–coated KB target cells in the presence of the NK cell–activating cytokine IL12, and these coculture supernatants induced significant T cell chemotaxis P < 0.001). F-IgG–coated targets also stimulated FcR-mediated monocyte effector functions. Studies in a murine leukemia model confirmed the intratumoral localization and antitumor activity of F-IgG, as well as enhancement of its effects by IL12 (P = 0.05). The antitumor effect of this combination was dependent on NK cells and led to decreased tumor cell proliferation in vivo. Thus, F-IgG can induce an immune response against FR-positive tumor cells that is mediated by NK cells and can be augmented by cytokine therapy. PMID:26865456

  15. Novel APC-like properties of human NK cells directly regulate T cell activation

    PubMed Central

    Hanna, Jacob; Gonen-Gross, Tsufit; Fitchett, Jonathan; Rowe, Tony; Daniels, Mark; Arnon, Tal I.; Gazit, Roi; Joseph, Aviva; Schjetne, Karoline W.; Steinle, Alexander; Porgador, Angel; Mevorach, Dror; Goldman-Wohl, Debra; Yagel, Simcha; LaBarre, Michael J.; Buckner, Jane H.; Mandelboim, Ofer

    2004-01-01

    Initiation of the adaptive immune response is dependent on the priming of naive T cells by APCs. Proteomic analysis of unactivated and activated human NK cell membrane–enriched fractions demonstrated that activated NK cells can efficiently stimulate T cells, since they upregulate MHC class II molecules and multiple ligands for TCR costimulatory molecules. Furthermore, by manipulating antigen administration, we show that NK cells possess multiple independent unique pathways for antigen uptake. These results highlight NK cell–mediated cytotoxicity and specific ligand recognition by cell surface–activating receptors on NK cells as unique mechanisms for antigen capturing and presentation. In addition, we analyzed the T cell–activating potential of human NK cells derived from different clinical conditions, such as inflamed tonsils and noninfected and CMV-infected uterine decidual samples, and from transporter-associated processing antigen 2–deficient patients. This in vivo analysis revealed that proinflammatory, but not immune-suppressive, microenvironmental requirements can selectively dictate upregulation of T cell–activating molecules on NK cells. Taken together, these observations offer new and unexpected insights into the direct interactions between NK and T cells and suggest novel APC-like activating functions for human NK cells. PMID:15578093

  16. The biology of NK cells and their receptors affects clinical outcomes after hematopoietic cell transplantation (HCT).

    PubMed

    Foley, Bree; Felices, Martin; Cichocki, Frank; Cooley, Sarah; Verneris, Michael R; Miller, Jeffrey S

    2014-03-01

    Natural killer (NK) cells were first identified for their capacity to reject bone marrow allografts in lethally irradiated mice without prior sensitization. Subsequently, human NK cells were detected and defined by their non-major histocompatibility complex (MHC)-restricted cytotoxicity toward transformed or virally infected target cells. Karre et al. later proposed 'the missing self hypothesis' to explain the mechanism by which self-tolerant cells could kill targets that had lost self MHC class I. Subsequently, the receptors that recognize MHC class I to mediate tolerance in the host were identified on NK cells. These class I-recognizing receptors contribute to the acquisition of function by a dynamic process known as NK cell education or licensing. In the past, NK cells were assumed to be short lived, but more recently NK cells have been shown to mediate immunologic memory to secondary exposures to cytomegalovirus infection. Because of their ability to lyse tumors with aberrant MHC class I expression and to produce cytokines and chemokines upon activation, NK cells may be primed by many stimuli, including viruses and inflammation, to contribute to a graft-versus-tumor effect. In addition, interactions with other immune cells support the therapeutic potential of NK cells to eradicate tumor and to enhance outcomes after hematopoietic cell transplantation.

  17. Targeting NK-cell checkpoints for cancer immunotherapy.

    PubMed

    Muntasell, Aura; Ochoa, Maria C; Cordeiro, Luna; Berraondo, Pedro; López-Díaz de Cerio, Ascension; Cabo, Mariona; López-Botet, Miguel; Melero, Ignacio

    2017-02-22

    Natural Killer (NK) cells are cytotoxic lymphocytes specialized in early defense against virus-infected and transformed cells. NK-cell function is regulated by activating and inhibitory surface receptors recognizing their ligands on transformed cells. Modulation of NK numbers and/or function by a variety of agents such as cytokines and monoclonal antibodies may result in enhanced anti-tumor activity. Recombinant cytokines (i.e., IL-15 and IL-2), antibodies blocking inhibitory receptors (i.e., KIR, NKG2A and TIGIT) and agonists delivering signals via CD137, NKG2D and CD16 stand out as the most suitable opportunities. These agents can be used to potentiate NKcell- mediated antibody-dependent cellular cytotoxicity (ADCC) against antibody-coated tumor cells, offering potential for multiple combinatorial immunotherapy strategies against cancer.

  18. Insufficient natural killer cell responses against retroviruses: how to improve NK cell killing of retrovirus-infected cells.

    PubMed

    Littwitz-Salomon, Elisabeth; Dittmer, Ulf; Sutter, Kathrin

    2016-11-08

    Natural killer (NK) cells belong to the innate immune system and protect against cancers and a variety of viruses including retroviruses by killing transformed or infected cells. They express activating and inhibitory receptors on their cell surface and often become activated after recognizing virus-infected cells. They have diverse antiviral effector functions like the release of cytotoxic granules, cytokine production and antibody dependent cellular cytotoxicity. The importance of NK cell activity in retroviral infections became evident due to the discovery of several viral strategies to escape recognition and elimination by NK cells. Mutational sequence polymorphisms as well as modulation of surface receptors and their ligands are mechanisms of the human immunodeficiency virus-1 to evade NK cell-mediated immune pressure. In Friend retrovirus infected mice the virus can manipulate molecular or cellular immune factors that in turn suppress the NK cell response. In this model NK cells lack cytokines for optimal activation and can be functionally suppressed by regulatory T cells. However, these inhibitory pathways can be overcome therapeutically to achieve full activation of NK cell responses and ultimately control dissemination of retroviral infection. One effective approach is to modulate the crosstalk between NK cells and dendritic cells, which produce NK cell-stimulating cytokines like type I interferons (IFN), IL-12, IL-15, and IL-18 upon retrovirus sensing or infection. Therapeutic administration of IFNα directly increases NK cell killing of retrovirus-infected cells. In addition, IL-2/anti-IL-2 complexes that direct IL-2 to NK cells have been shown to significantly improve control of retroviral infection by NK cells in vivo. In this review, we describe novel approaches to improve NK cell effector functions in retroviral infections. Immunotherapies that target NK cells of patients suffering from viral infections might be a promising treatment option for the

  19. Murine peripheral NK-cell populations originate from site-specific immature NK cells more than from BM-derived NK cells.

    PubMed

    Pinhas, Nissim; Sternberg-Simon, Michal; Chiossone, Laura; Shahaf, Gitit; Walzer, Thierry; Vivier, Eric; Mehr, Ramit

    2016-05-01

    Murine NK cells can be divided by the expression of two cell surface markers, CD27 and Mac-1 (a.k.a. CD11b), into four separate subsets. These subsets suggest a linear development model: CD27(-) Mac-1(-) → CD27(+) Mac-1(-) → CD27(+) Mac-1(+) → CD27(-) Mac-1(+) . Here, we used a combination of BrdU labeling experiments and mathematical modeling to gain insights regarding NK-cell development in mouse bone marrow (BM), spleen and liver. The modeling results that best fit the experimental data show that the majority of NK cells already express CD27 upon entering the NK-cell developmental pathway. Additionally, only a small fraction of NK cells exit the BM to other sites, suggesting that peripheral NK-cell populations originate from site-specific immature NK cells more than from BM-derived mature NK cells.

  20. An NK cell line (haNK) expressing high levels of granzyme and engineered to express the high affinity CD16 allele

    PubMed Central

    Jochems, Caroline; Hodge, James W.; Fantini, Massimo; Fujii, Rika; Maurice, Y. Morillon; Greiner, John W.; Padget, Michelle R.; Tritsch, Sarah R.; Tsang, Kwong Yok; Campbell, Kerry S.; Klingemann, Hans; Boissel, Laurent; Rabizadeh, Shahrooz; Soon-Shiong, Patrick; Schlom, Jeffrey

    2016-01-01

    Natural killer (NK) cells are known to play a role in mediating innate immunity, in enhancing adaptive immune responses, and have been implicated in mediating anti-tumor responses via antibody-dependent cell-mediated cytotoxicity (ADCC) by reactivity of CD16 with the Fc region of human IgG1 antibodies. The NK-92 cell line, derived from a lymphoma patient, has previously been well characterized and adoptive transfer of irradiated NK-92 cells has demonstrated safety and shown preliminary evidence of clinical benefit in cancer patients. The NK-92 cell line, devoid of CD16, has now been engineered to express the high affinity (ha) CD16 V158 FcγRIIIa receptor, as well as engineered to express IL-2; IL-2 has been shown to replenish the granular stock of NK cells, leading to enhanced perforin- and granzyme-mediated lysis of tumor cells. The studies reported here show high levels of granzyme in haNK cells, and demonstrate the effects of irradiation of haNK cells on multiple phenotypic markers, viability, IL-2 production, and lysis of a spectrum of human tumor cells. Studies also compare endogenous irradiated haNK lysis of tumor cells with that of irradiated haNK-mediated ADCC using cetuximab, trastuzumab and pertuzumab monoclonal antibodies. These studies thus provide the rationale for the potential use of irradiated haNK cells in adoptive transfer studies for a range of human tumor types. Moreover, since only approximately 10% of humans are homozygous for the high affinity V CD16 allele, these studies also provide the rationale for the use of irradiated haNK cells in combination with IgG1 anti-tumor monoclonal antibodies. PMID:27861156

  1. Evaluation of Functional NK Cell Responses in Vaccinated and SIV-Infected Rhesus Macaques.

    PubMed

    Vargas-Inchaustegui, Diego A; Ying, Olivia; Demberg, Thorsten; Robert-Guroff, Marjorie

    2016-01-01

    NK cells are crucial components of the innate immune system due to their capacity to exert rapid cytotoxic and immunomodulatory function in the absence of prior sensitization. NK cells can become activated by exposure to target cells and/or by cytokines produced by antigen-presenting cells. In this study, we examined the effects of a simian immunodeficiency virus (SIV) vaccine regimen and subsequent SIV infection on the cytotoxic and immunomodulatory functions of circulatory NK cells. While vaccination did not significantly impact the capacity of NK cells to kill MHC-devoid 721.221 target cells, SIV-infection led to a significant decrease in target cell killing. NK cells from uninfected macaques were responsive to a low dose (5 ng/ml) of IL-15 pre-activation, leading to significant increases in their cytotoxic potential, however, NK cells from SIV-infected macaques required a higher dose (50 ng/ml) of IL-15 pre-activation in order to significantly increase their cytotoxic potential. By contrast, no differences were observed in the capacity of NK cells from vaccinated and SIV-infected macaques to respond to IL-12 and IL-18. Similarly, NK cells both before and after infection exhibited equivalent responses to Fc-mediated activation. Collectively, our results show that early SIV-infection impairs the natural cytotoxic capacity of circulatory NK cells without affecting Fc-mediated or cytokine-producing function.

  2. Myeloma cells resistance to NK cell lysis mainly involves an HLA class I-dependent mechanism.

    PubMed

    Gao, Minjie; Gao, Lu; Yang, Guang; Tao, Yi; Hou, Jun; Xu, Hongwei; Hu, Xiaojing; Han, Ying; Zhang, Qianqiao; Zhan, Fenghuang; Wu, Xiaosong; Shi, Jumei

    2014-07-01

    The anti-multiple myeloma (MM) potential of natural killer (NK) cells has been of rising interest in recent years. However, the molecular mechanism of NK cell cytotoxicity to myeloma cells remains unclear. In the present study, we investigated the expressions of human leukocyte antigen (HLA) class I and HLA-G in patient myeloma cells, and determined their relevance in patient tumor-cell susceptibility to NK cell cytotoxicity. Our results showed that patient myeloma cells (n = 12) were relatively resistant to NK-92 cell lysis, compared with myeloma cell lines (n = 7, P < 0.01). Gene expression profiling and flow cytometry analysis showed that both mRNA and protein of HLA class I were highly expressed in 12 patient myeloma cells. Interestingly, no or low HLA-G surface expression was detected, although multiple HLA-G transcripts were detected in these myeloma cells. NK cell function assay showed that down-regulating HLA class I expression on patient cells by acid treatment significantly increased the susceptibility of MM cells to NK-mediated lysis. Furthermore, we found that the blocking of membrane-bound HLA class I rather than HLA-G using antibodies on myeloma samples markedly increased their susceptibility to NK-mediated killing. These results demonstrated that the resistance of patient MM cells to NK lysis mainly involves an HLA class I-dependent mechanism, suggesting that HLA class I may be involved in protecting MM cells from NK-mediated attack and contribute to their immune escape in vivo.

  3. Uptake of poly-dispersed single-walled carbon nanotubes and decline of functions in mouse NK cells undergoing activation.

    PubMed

    Alam, Anwar; Puri, Niti; Saxena, Rajiv K

    2016-09-01

    The interaction of poly-dispersed acid-functionalized single-walled carbon nanotubes (AF-SWCNT) with NK cells undergoing activation was examined. Exposure to AF-SWCNT during NK activation in vitro by interleukin (IL)-2, and in vivo by Poly(I:C) significantly lowered cytotoxic activity generated against YAC-1 tumor cells. Recoveries of spleen NK1.1(+) cells as well as the activated subset of NK cells (NK1.1(+)CD69(+) cells) were significantly reduced by the AF-SWCNT exposure. The proportion of apoptotic NK cells (NK1.1(+) phosphatidylserine(+)) in the spleen cell preparations activated in vitro was also significantly elevated. Expression levels of CD107a [for assessing NK cell degranulation] as well as of FasL marker [mediating non-secretory pathway of NK cell killing] were significantly lower in cells exposed to AF-SWCNT during the activation phase. Intracellular levels of interferon (IFN)-γ and tumor necrosis factor (TNF)-α in the cells were also significantly reduced. Fluorescent AF-SWCNT (FAF-SWCNT) were internalized by the NK cells and uptake was significantly greater in activated cells. Confocal microscopy indicated the internalized FAF-SWCNT were localized to the cytoplasm of the NK cells. These results indicated that AF-SWCNT were internalized by NK cells and caused a general down-regulation of a variety of parameters associated with NK cell cytotoxicity and other cellular functions.

  4. Engagement of TLR3, TLR7, and NKG2D regulate IFN-gamma secretion but not NKG2D-mediated cytotoxicity by human NK cells stimulated with suboptimal doses of IL-12.

    PubMed

    Girart, María V; Fuertes, Mercedes B; Domaica, Carolina I; Rossi, Lucas E; Zwirner, Norberto W

    2007-09-15

    NK cells express different TLRs, such as TLR3, TLR7, and TLR9, but little is known about their role in NK cell stimulation. In this study, we used specific agonists (poly(I:C), loxoribine, and synthetic oligonucleotides containing unmethylated CpG sequences to stimulate human NK cells without or with suboptimal doses of IL-12, IL-15, or IFN-alpha, and investigated the secretion of IFN-gamma, cytotoxicity, and expression of the activating receptor NKG2D. Poly(I:C) and loxoribine, in conjunction with IL-12, but not IL-15, triggered secretion of IFN-gamma. Inhibition of IFN-gamma secretion by chloroquine suggested that internalization of the TLR agonists was necessary. Also, secretion of IFN-gamma was dependent on MEK1/ERK, p38 MAPK, p70(S6) kinase, and NF-kappaB, but not on calcineurin. IFN-alpha induced a similar effect, but promoted lesser IFN-gamma secretion. However, cytotoxicity (51Cr release assays) against MHC class I-chain related A (MICA)- and MICA+ tumor targets remained unchanged, as well as the expression of the NKG2D receptor. Excitingly, IFN-gamma secretion was significantly increased when NK cells were stimulated with poly(I:C) or loxoribine and IL-12, and NKG2D engagement was induced by coculture with MICA+ tumor cells in a PI3K-dependent manner. We conclude that resting NK cells secrete high levels of IFN-gamma in response to agonists of TLR3 or TLR7 and IL-12, and this effect can be further enhanced by costimulation through NKG2D. Hence, integration of the signaling cascades that involve TLR3, TLR7, IL-12, and NKG2D emerges as a critical step to promote IFN-gamma-dependent NK cell-mediated effector functions, which could be a strategy to promote Th1-biased immune responses in pathological situations such as cancer.

  5. NK1.1 cells and CD8 T cells mediate the antitumor activity of Cl-IB-MECA in a mouse melanoma model.

    PubMed

    Morello, Silvana; Sorrentino, Rosalinda; Montinaro, Antonella; Luciano, Antonio; Maiolino, Piera; Ngkelo, Anta; Arra, Claudio; Adcock, Ian M; Pinto, Aldo

    2011-04-01

    Cl-IB-MECA, synthetic A(3) adenosine receptor agonist, is a potential anticancer agent. In this study, we have examined the effect of Cl-IB-MECA in a mouse melanoma model. Cl-IB-MECA significantly inhibited tumor growth in immune-competent mice. Notably, the number of tumor-infiltrating NK1.1(+) cells and CD8(+) T cells was significantly increased in Cl-IB-MECA-treated mice. This effect was correlated with high levels of tumor necrosis factor α (TNF-α) and interferon γ in melanoma tissue. Depletion of either CD8(+) T cells or NK1.1(+) cells completely abrogated the antitumor effect of Cl-IB-MECA. Accordingly, Cl-IB-MECA did not affect tumor growth in nude mice. In addition, we also found that the number of mature and active conventional dendritic cells at the tumor site was increased after Cl-IB-MECA administration. Moreover, Cl-IB-MECA significantly increased TNF-α and IL-12p40 release from splenic CD11c(+) cells. In conclusion, our study provides novel insights into the mechanism by which Cl-IB-MECA leads to an effective antitumor response that involves the activation of natural killer cells and CD8(+) T cells and further highlights its therapeutic potential.

  6. CD19-CAR engineered NK-92 cells are sufficient to overcome NK cell resistance in B-cell malignancies.

    PubMed

    Romanski, Annette; Uherek, Christoph; Bug, Gesine; Seifried, Erhard; Klingemann, Hans; Wels, Winfried S; Ottmann, Oliver G; Tonn, Torsten

    2016-07-01

    Many B-cell acute and chronic leukaemias tend to be resistant to killing by natural killer (NK) cells. The introduction of chimeric antigen receptors (CAR) into T cells or NK cells could potentially overcome this resistance. Here, we extend our previous observations on the resistance of malignant lymphoblasts to NK-92 cells, a continuously growing NK cell line, showing that anti-CD19-CAR (αCD19-CAR) engineered NK-92 cells can regain significant cytotoxicity against CD19 positive leukaemic cell lines and primary leukaemia cells that are resistant to cytolytic activity of parental NK-92 cells. The 'first generation' CAR was generated from a scFv (CD19) antibody fragment, coupled to a flexible hinge region, the CD3ζ chain and a Myc-tag and cloned into a retrovirus backbone. No difference in cytotoxic activity of NK-92 and transduced αCD19-CAR NK-92 cells towards CD19 negative targets was found. However, αCD19-CAR NK-92 cells specifically and efficiently lysed CD19 expressing B-precursor leukaemia cell lines as well as lymphoblasts from leukaemia patients. Since NK-92 cells can be easily expanded to clinical grade numbers under current Good Manufactoring Practice (cGMP) conditions and its safety has been documented in several phase I clinical studies, treatment with CAR modified NK-92 should be considered a treatment option for patients with lymphoid malignancies.

  7. Suppressive effect of a standardized mistletoe extract on the expression of activatory NK receptors and function of human NK cells.

    PubMed

    Lee, Soo Jung; Son, Young-Ok; Kim, Hyunjin; Kim, Joo-Young; Park, Soon-Won; Bae, Jae-Ho; Kim, Hyung Hoi; Lee, Eun-Yup; Chung, Byung-Seon; Kim, Sun-Hee; Kang, Chi-Dug

    2007-09-01

    Despite long-term use of mistletoe extracts for cancer treatment, their mode of action remains elusive. In this study, it was studied in vitro if mistletoe extract is able to modulate the expression of natural cytotoxic receptors (NCRs) and NKG2D receptor, which stimulate natural killer cell-mediated cytotoxicity. Unexpectedly, a mistletoe extract, ABNOBA viscum Fraxini, inhibited the expression level of NKp46 and NKG2D receptors in dose- and time-dependent manners. The levels of NKp30 and NKG2D receptors were remarkably induced and NKp44 was slightly induced after 48 h treatment with IL-2 and IL-15 in both mRNA and surface expression. The activatory NK receptors were not induced significantly after treatment with IL-12, IL-18, and IL-21 for 48 h. Induction of activatory NK receptors by IL-2 and IL-15 was suppressed almost to the untreated levels by treatment with mistletoe extract, which appeared to induce apoptosis of NK cells in a dose-dependent manner. However, the treatment with IL-2 and IL-15 did not prevent the mistletoe-induced NK-cell death. Mistletoe extract inhibited significantly the cytotoxic activity of resting and IL-2- or IL-15-stimulated NK cells. These results suggest that inhibition of survival and function of NK cells by mistletoe extract may curtail in part the therapeutic effects of mistletoe.

  8. Broadly impaired NK cell function in non-obese diabetic mice is partially restored by NK cell activation in vivo and by IL-12/IL-18 in vitro.

    PubMed

    Johansson, Sofia E; Hall, Håkan; Björklund, Jens; Höglund, Petter

    2004-01-01

    NK cells represent a link between innate and adaptive immunity, and may play a role in regulating autoimmune disorders. We have characterized the NK cell population in non-obese diabetic (NOD) mice. The percentage and absolute numbers of NK cells were similar in NOD and control MHC-matched B6.g7 mice. However, the capacity of NOD NK cells to mediate natural cytotoxicity as well as FcR- and Ly49D-mediated killing was compromised in vitro, suggesting a defect affecting multiple activation pathways. The defect was neither linked to the NK gene complex nor to the MHC, as determined by comparison with mice congenic for these regions. Introducing the beta(2)-microglobulin mutation on the NOD background further impaired NK cell function, showing that the compromised cytotoxic capacity in these two strains arises from two independent mechanisms. In vivo rejection responses against tumor cells and against MHC class I-deficient spleen cells were decreased in naive NOD recipients, but restored in mice pre-activated with tilorone, a potent activator of NK cells. In addition, killing of some tumor targets was restored in vitro after activation of NK cells with IL-12 plus IL-18 or with IFN-alpha/beta, but not with IL-2. Interestingly, natural killing of RMA-S targets by NOD NK cells could not be restored in vitro, indicating that restoration of killing capacity was only partial. Our data suggest a severe, but partially restorable, killing defect in NOD NK cells, affecting activation through several pathways.

  9. Protocol for the clonal analysis of NK cell effector functions by multi-parameter flow cytometry.

    PubMed

    Schönberg, Kathrin; Hejazi, Maryam; Uhrberg, Markus

    2012-01-01

    Natural killer (NK) cells provide a first line of defense against viral infections and prepare the ground for subsequent action of virus-specific T cells in a concerted way. Human NK cells use a sophisticated system of inhibitory and stimulatory receptors of the killer cell immunoglobulin-like receptor (KIR) gene family, which are expressed in a clonally distributed manner. Several studies suggest that KIR play a critical role in NK cell-mediated protection against HCV and HIV infection. As each NK cell expresses an individual set of KIR receptors that enables them to sense differences in HLA class I expression, classical measurement of NK cell function by analysis of target cell killing does not enable one to define and isolate the clinically relevant NK cell effector subsets. Here, we have developed a flow cytometry-based protocol to measure cytolytic activity together with KIR expression at a clonal level. Combined analysis of KIR expression in conjunction with cell surface mobilization of CD107 enables precise enumeration of cytolytic NK cells with defined specificity for HLA class I. Moreover, via inclusion of intracellular perforin or alternatively granzyme B, NK cells with deficient loading of cytotoxic granula can be identified. The present protocol enables identification and isolation of cytotoxic NK cells on a clonal level and enables reliable measurement in healthy as well as in pathological settings such as virus infection and hematological disease.

  10. Combination Immune Therapies to Enhance Anti-Tumor Responses by NK Cells

    PubMed Central

    Mentlik James, Ashley; Cohen, Adam D.; Campbell, Kerry S.

    2013-01-01

    Natural killer (NK) cells are critical innate immune lymphocytes capable of destroying virally infected or cancerous cells through targeted cytotoxicity and further assisting in the immune response by releasing inflammatory cytokines. NK cells are thought to contribute to the process of tumor killing by certain therapeutic monoclonal antibodies (mAb) by directing antibody-dependent cellular cytotoxicity (ADCC) through FcγRIIIA (CD16). Numerous therapeutic mAb have been developed that target distinct cancer-specific cell markers and may direct NK cell-mediated ADCC. Recent therapeutic approaches have combined some of these cancer-specific mAb with additional strategies to optimize NK cell cytotoxicity. These include agonistic mAb targeting NK cell activating receptors and mAbs blocking NK cell inhibitory receptors to enhance NK cell functions. Furthermore, several drugs that can potentiate NK cell cytotoxicity through other mechanisms are being used in combination with therapeutic mAb. In this review, we examine the mechanisms employed by several promising agents used in combination therapies that enhance natural or Ab-dependent cytotoxicity of cancer cells by NK cells, with a focus on treatments for leukemia and multiple myeloma. PMID:24391651

  11. Neutralization of (NK-cell-derived) B-cell activating factor by Belimumab restores sensitivity of chronic lymphoid leukemia cells to direct and Rituximab-induced NK lysis.

    PubMed

    Wild, J; Schmiedel, B J; Maurer, A; Raab, S; Prokop, L; Stevanović, S; Dörfel, D; Schneider, P; Salih, H R

    2015-08-01

    Natural killer (NK) cells are cytotoxic lymphocytes that substantially contribute to the therapeutic benefit of antitumor antibodies like Rituximab, a crucial component in the treatment of B-cell malignancies. In chronic lymphocytic leukemia (CLL), the ability of NK cells to lyse the malignant cells and to mediate antibody-dependent cellular cytotoxicity upon Fc receptor stimulation is compromised, but the underlying mechanisms are largely unclear. We report here that NK-cells activation-dependently produce the tumor necrosis factor family member 'B-cell activating factor' (BAFF) in soluble form with no detectable surface expression, also in response to Fc receptor triggering by therapeutic CD20-antibodies. BAFF in turn enhanced the metabolic activity of primary CLL cells and impaired direct and Rituximab-induced lysis of CLL cells without affecting NK reactivity per se. The neutralizing BAFF antibody Belimumab, which is approved for treatment of systemic lupus erythematosus, prevented the effects of BAFF on the metabolism of CLL cells and restored their susceptibility to direct and Rituximab-induced NK-cell killing in allogeneic and autologous experimental systems. Our findings unravel the involvement of BAFF in the resistance of CLL cells to NK-cell antitumor immunity and Rituximab treatment and point to a benefit of combinatory approaches employing BAFF-neutralizing drugs in B-cell malignancies.

  12. Lenalidomide augments actin remodeling and lowers NK-cell activation thresholds

    PubMed Central

    Lagrue, Kathryn; Carisey, Alex; Morgan, David J.; Chopra, Rajesh

    2015-01-01

    As multiple myeloma (MM) progresses, natural killer (NK)-cell responses decline against malignant plasma cells. The immunomodulatory drug lenalidomide is widely used for treatment of MM but its influence on NK-cell biology is unclear. Here, we report that lenalidomide lowers the threshold for NK-cell activation, causing a 66% decrease in the 50% effective concentration (EC50) for activation through CD16, and a 38% decrease in EC50 for NK group 2 member D (NKG2D)–mediated activation, allowing NK cells to respond to lower doses of ligand. In addition, lenalidomide augments NK-cell responses, causing a twofold increase in the proportion of primary NK cells producing interferon-γ (IFN-γ), and a 20-fold increase in the amount of IFN-γ produced per cell. Importantly, lenalidomide did not trigger IFN-γ production in unstimulated NK cells. Thus, lenalidomide enhances the NK-cell arm of the immune response, without activating NK cells inappropriately. Of particular clinical importance, lenalidomide also allowed NK cells to be activated by lower doses of rituximab, an anti-CD20 monoclonal antibody (mAb) widely used to treat B-cell malignancies. This supports combined use of lenalidomide and rituximab in a clinical setting. Finally, superresolution microscopy revealed that lenalidomide increased the periodicity of cortical actin at immune synapses, resulting in an increase in the area of the actin mesh predicted to be penetrable to vesicles containing IFN-γ. NK cells from MM patients also responded to lenalidomide in this way. This indicates that nanometer-scale rearrangements in cortical actin, a recently discovered step in immune synapse assembly, are a potential new target for therapeutic compounds. PMID:26002964

  13. Lenalidomide augments actin remodeling and lowers NK-cell activation thresholds.

    PubMed

    Lagrue, Kathryn; Carisey, Alex; Morgan, David J; Chopra, Rajesh; Davis, Daniel M

    2015-07-02

    As multiple myeloma (MM) progresses, natural killer (NK)-cell responses decline against malignant plasma cells. The immunomodulatory drug lenalidomide is widely used for treatment of MM but its influence on NK-cell biology is unclear. Here, we report that lenalidomide lowers the threshold for NK-cell activation, causing a 66% decrease in the 50% effective concentration (EC50) for activation through CD16, and a 38% decrease in EC50 for NK group 2 member D (NKG2D)-mediated activation, allowing NK cells to respond to lower doses of ligand. In addition, lenalidomide augments NK-cell responses, causing a twofold increase in the proportion of primary NK cells producing interferon-γ (IFN-γ), and a 20-fold increase in the amount of IFN-γ produced per cell. Importantly, lenalidomide did not trigger IFN-γ production in unstimulated NK cells. Thus, lenalidomide enhances the NK-cell arm of the immune response, without activating NK cells inappropriately. Of particular clinical importance, lenalidomide also allowed NK cells to be activated by lower doses of rituximab, an anti-CD20 monoclonal antibody (mAb) widely used to treat B-cell malignancies. This supports combined use of lenalidomide and rituximab in a clinical setting. Finally, superresolution microscopy revealed that lenalidomide increased the periodicity of cortical actin at immune synapses, resulting in an increase in the area of the actin mesh predicted to be penetrable to vesicles containing IFN-γ. NK cells from MM patients also responded to lenalidomide in this way. This indicates that nanometer-scale rearrangements in cortical actin, a recently discovered step in immune synapse assembly, are a potential new target for therapeutic compounds.

  14. Influenza Virus Targets Class I MHC-Educated NK Cells for Immunoevasion.

    PubMed

    Mahmoud, Ahmad Bakur; Tu, Megan M; Wight, Andrew; Zein, Haggag S; Rahim, Mir Munir A; Lee, Seung-Hwan; Sekhon, Harman S; Brown, Earl G; Makrigiannis, Andrew P

    2016-02-01

    The immune response to influenza virus infection comprises both innate and adaptive defenses. NK cells play an early role in the destruction of tumors and virally-infected cells. NK cells express a variety of inhibitory receptors, including those of the Ly49 family, which are functional homologs of human killer-cell immunoglobulin-like receptors (KIR). Like human KIR, Ly49 receptors inhibit NK cell-mediated lysis by binding to major histocompatibility complex class I (MHC-I) molecules that are expressed on normal cells. During NK cell maturation, the interaction of NK cell inhibitory Ly49 receptors with their MHC-I ligands results in two types of NK cells: licensed ("functional"), or unlicensed ("hypofunctional"). Despite being completely dysfunctional with regard to rejecting MHC-I-deficient cells, unlicensed NK cells represent up to half of the mature NK cell pool in rodents and humans, suggesting an alternative role for these cells in host defense. Here, we demonstrate that after influenza infection, MHC-I expression on lung epithelial cells is upregulated, and mice bearing unlicensed NK cells (Ly49-deficient NKCKD and MHC-I-deficient B2m-/- mice) survive the infection better than WT mice. Importantly, transgenic expression of an inhibitory self-MHC-I-specific Ly49 receptor in NKCKD mice restores WT influenza susceptibility, confirming a direct role for Ly49. Conversely, F(ab')2-mediated blockade of self-MHC-I-specific Ly49 inhibitory receptors protects WT mice from influenza virus infection. Mechanistically, perforin-deficient NKCKD mice succumb to influenza infection rapidly, indicating that direct cytotoxicity is necessary for unlicensed NK cell-mediated protection. Our findings demonstrate that Ly49:MHC-I interactions play a critical role in influenza virus pathogenesis. We suggest a similar role may be conserved in human KIR, and their blockade may be protective in humans.

  15. Repression of GSK3 restores NK cell cytotoxicity in AML patients.

    PubMed

    Parameswaran, Reshmi; Ramakrishnan, Parameswaran; Moreton, Stephen A; Xia, Zhiqiang; Hou, Yongchun; Lee, Dean A; Gupta, Kalpana; deLima, Marcos; Beck, Rose C; Wald, David N

    2016-04-04

    Natural killer cells from acute myeloid leukaemia patients (AML-NK) show a dramatic impairment in cytotoxic activity. The exact reasons for this dysfunction are not fully understood. Here we show that the glycogen synthase kinase beta (GSK3β) expression is elevated in AML-NK cells. Interestingly, GSK3 overexpression in normal NK cells impairs their ability to kill AML cells, while genetic or pharmacological GSK3 inactivation enhances their cytotoxic activity. Mechanistic studies reveal that the increased cytotoxic activity correlates with an increase in AML-NK cell conjugates. GSK3 inhibition promotes the conjugate formation by upregulating LFA expression on NK cells and by inducing ICAM-1 expression on AML cells. The latter is mediated by increased NF-κB activation in response to TNF-α production by NK cells. Finally, GSK3-inhibited NK cells show significant efficacy in human AML mouse models. Overall, our work provides mechanistic insights into the AML-NK dysfunction and a potential NK cell therapy strategy.

  16. Phenotypic profile of expanded NK cells in chronic lymphoproliferative disorders: a surrogate marker for NK-cell clonality

    PubMed Central

    Bárcena, Paloma; Jara-Acevedo, María; Tabernero, María Dolores; López, Antonio; Sánchez, María Luz; García-Montero, Andrés C.; Muñoz-García, Noemí; Vidriales, María Belén; Paiva, Artur; Lecrevisse, Quentin; Lima, Margarida; Langerak, Anton W.; Böttcher, Sebastian; van Dongen, Jacques J.M.

    2015-01-01

    Currently, the lack of a universal and specific marker of clonality hampers the diagnosis and classification of chronic expansions of natural killer (NK) cells. Here we investigated the utility of flow cytometric detection of aberrant/altered NK-cell phenotypes as a surrogate marker for clonality, in the diagnostic work-up of chronic lymphoproliferative disorders of NK cells (CLPD-NK). For this purpose, a large panel of markers was evaluated by multiparametric flow cytometry on peripheral blood (PB) CD56low NK cells from 60 patients, including 23 subjects with predefined clonal (n = 9) and polyclonal (n = 14) CD56low NK-cell expansions, and 37 with CLPD-NK of undetermined clonality; also, PB samples from 10 healthy adults were included. Clonality was established using the human androgen receptor (HUMARA) assay. Clonal NK cells were found to show decreased expression of CD7, CD11b and CD38, and higher CD2, CD94 and HLADR levels vs. normal NK cells, together with a restricted repertoire of expression of the CD158a, CD158b and CD161 killer-associated receptors. In turn, NK cells from both clonal and polyclonal CLPD-NK showed similar/overlapping phenotypic profiles, except for high and more homogeneous expression of CD94 and HLADR, which was restricted to clonal CLPD-NK. We conclude that the CD94hi/HLADR+ phenotypic profile proved to be a useful surrogate marker for NK-cell clonality. PMID:26556869

  17. Phenotypic profile of expanded NK cells in chronic lymphoproliferative disorders: a surrogate marker for NK-cell clonality.

    PubMed

    Bárcena, Paloma; Jara-Acevedo, María; Tabernero, María Dolores; López, Antonio; Sánchez, María Luz; García-Montero, Andrés C; Muñoz-García, Noemí; Vidriales, María Belén; Paiva, Artur; Lecrevisse, Quentin; Lima, Margarida; Langerak, Anton W; Böttcher, Sebastian; van Dongen, Jacques J M; Orfao, Alberto; Almeida, Julia

    2015-12-15

    Currently, the lack of a universal and specific marker of clonality hampers the diagnosis and classification of chronic expansions of natural killer (NK) cells. Here we investigated the utility of flow cytometric detection of aberrant/altered NK-cell phenotypes as a surrogate marker for clonality, in the diagnostic work-up of chronic lymphoproliferative disorders of NK cells (CLPD-NK). For this purpose, a large panel of markers was evaluated by multiparametric flow cytometry on peripheral blood (PB) CD56(low) NK cells from 60 patients, including 23 subjects with predefined clonal (n = 9) and polyclonal (n = 14) CD56(low) NK-cell expansions, and 37 with CLPD-NK of undetermined clonality; also, PB samples from 10 healthy adults were included. Clonality was established using the human androgen receptor (HUMARA) assay. Clonal NK cells were found to show decreased expression of CD7, CD11b and CD38, and higher CD2, CD94 and HLADR levels vs. normal NK cells, together with a restricted repertoire of expression of the CD158a, CD158b and CD161 killer-associated receptors. In turn, NK cells from both clonal and polyclonal CLPD-NK showed similar/overlapping phenotypic profiles, except for high and more homogeneous expression of CD94 and HLADR, which was restricted to clonal CLPD-NK. We conclude that the CD94(hi)/HLADR+ phenotypic profile proved to be a useful surrogate marker for NK-cell clonality.

  18. Perturbation of NK cell peripheral homeostasis accelerates prostate carcinoma metastasis

    PubMed Central

    Liu, Gang; Lu, Shengjun; Wang, Xuanjun; Page, Stephanie T.; Higano, Celestia S.; Plymate, Stephen R.; Greenberg, Norman M.; Sun, Shaoli; Li, Zihai; Wu, Jennifer D.

    2013-01-01

    The activating receptor NK cell group 2 member D (NKG2D) mediates antitumor immunity in experimental animal models. However, whether NKG2D ligands contribute to tumor suppression or progression clinically remains controversial. Here, we have described 2 novel lines of “humanized” bi-transgenic (bi-Tg) mice in which native human NKG2D ligand MHC class I polypeptide-related sequence B (MICB) or the engineered membrane-restricted MICB (MICB.A2) was expressed in the prostate of the transgenic adenocarcinoma of the mouse prostate (TRAMP) model of spontaneous carcinogenesis. Bi-Tg TRAMP/MICB mice exhibited a markedly increased incidence of progressed carcinomas and metastasis, whereas TRAMP/MICB.A2 mice enjoyed long-term tumor-free survival conferred by sustained NKG2D-mediated antitumor immunity. Mechanistically, we found that cancer progression in TRAMP/MICB mice was associated with loss of the peripheral NK cell pool owing to high serum levels of tumor-derived soluble MICB (sMICB). Prostate cancer patients also displayed reduction of peripheral NK cells and high sMIC levels. Our study has not only provided direct evidence in “humanized” mouse models that soluble and membrane-restricted NKG2D ligands pose opposite impacts on cancer progression, but also uncovered a mechanism of sMIC-induced impairment of NK cell antitumor immunity. Our findings suggest that the impact of soluble NKG2D ligands should be considered in NK cell–based cancer immunotherapy and that our unique mouse models should be valuable for therapy optimization. PMID:24018560

  19. Tumor-Associated Monocytes/Macrophages Impair NK-Cell Function via TGFβ1 in Human Gastric Cancer.

    PubMed

    Peng, Liu-Sheng; Zhang, Jin-Yu; Teng, Yong-Sheng; Zhao, Yong-Liang; Wang, Ting-Ting; Mao, Fang-Yuan; Lv, Yi-Pin; Cheng, Ping; Li, Wen-Hua; Chen, Na; Duan, Mubing; Chen, Weisan; Guo, Gang; Zou, Quan-Ming; Zhuang, Yuan

    2017-03-01

    Natural killer (NK) cells are a major component of the host antitumor immune response in human cancer. However, the nature, functional regulation, and clinical relevance of NK cells in gastric cancer remain largely unknown. In this study, we showed that the percentages of NK cells in tumors were significantly decreased, and low percentages of tumor-infiltrating NK cells were positively correlated with poor survival and disease progression. Although the expression of activating and inhibitory receptors on NK cells was shown to be not different between tumor and nontumor tissues, NK cells in tumors had impaired effector functions, characterized by decreased IFNγ, TNFα, and Ki-67 expression. We found that tumor-infiltrating monocytes/macrophages were physically close to NK cells, and their percentages negatively correlated with IFNγ(+) and TNFα(+) NK-cell percentages. Ex vivo study showed that isolated tumor-associated monocytes/macrophages could impair NK-cell expression of IFNγ, TNFα, and Ki-67. Blockade of TGFβ1 attenuated such monocytes/macrophages-mediated impairment of NK-cell function. Our data suggest that human NK-cell function was impaired by tumor-associated monocytes/macrophages, and that restoring NK-cell function may be an important therapeutic strategy to prevent tumor immune escape in gastric cancer. Cancer Immunol Res; 5(3); 248-56. ©2017 AACR.

  20. Location and cellular stages of NK cell development

    PubMed Central

    Yu, Jianhua; Freud, Aharon G.; Caligiuri, Michael A

    2013-01-01

    The identification of distinct tissue-specific natural killer (NK) cell populations that apparently mature from local precursor populations has brought new insight into the diversity and developmental regulation of this important lymphoid subset. NK cells provide a necessary link between the early (innate) and late (adaptive) immune responses to infection. Gaining a better understanding of the processes that govern NK cell development should allow us to better harness NK cell functions in multiple clinical settings as well as to gain further insight into how these cells undergo malignant transformation. In this review, we summarize recent advances in understanding sites and cellular stages of NK cell development in humans and mice. PMID:24055329

  1. Dysregulation of regulatory CD56(bright) NK cells/T cells interactions in multiple sclerosis.

    PubMed

    Laroni, Alice; Armentani, Eric; Kerlero de Rosbo, Nicole; Ivaldi, Federico; Marcenaro, Emanuela; Sivori, Simona; Gandhi, Roopali; Weiner, Howard L; Moretta, Alessandro; Mancardi, Giovanni L; Uccelli, Antonio

    2016-08-01

    Recent evidence has shown that CD56(bright) NK cells, a subset of NK cells abundant in lymph nodes, may have an immunoregulatory function. In multiple sclerosis (MS), expansion of CD56(bright) NK cells has been associated to successful response to different treatments and to remission of disease during pregnancy; how whether they exert immunoregulation in physiologic conditions and whether this is impaired in MS is not known. We dissected the immunoregulatory role of CD56(bright) NK cells function in healthy subjects (HS) and compared it with that of untreated MS subjects or patients with clinically isolated syndrome suggestive of MS (CIS). We found that CD56(bright) NK cells from HS acquire, upon inflammatory cues, the capability of suppressing autologous CD4+T cell proliferation through direct cytotoxicity requiring engagement of natural cytotoxicity receptors (NCRs) and secretion of granzyme B. CD56(bright) NK cells from patients with MS/CIS did not differ in frequency and share a similar phenotype but displayed a significantly lower ability to inhibit autologous T cell proliferation. This impairment was not related to deficient expression of NCRs or granzyme B by CD56(bright) NK cells, but to increased HLA-E expression on T cells from MS/CIS subjects, which could enhance the inhibitory effect mediated by NKG2A that is homogeneously expressed on CD56(bright) NK cells. The defect in controlling autologous T cells by CD56(bright) NK cells in MS/CIS might contribute to the excess of autoimmune response that is associated to disease development.

  2. Human immunodeficiency-causing mutation defines CD16 in spontaneous NK cell cytotoxicity.

    PubMed

    Grier, Jennifer T; Forbes, Lisa R; Monaco-Shawver, Linda; Oshinsky, Jennifer; Atkinson, T Prescott; Moody, Curtis; Pandey, Rahul; Campbell, Kerry S; Orange, Jordan S

    2012-10-01

    The Fc receptor on NK cells, FcγRIIIA (CD16), has been extensively studied for its role in mediating antibody-dependent cellular cytotoxicity (ADCC). A homozygous missense mutation in CD16 (encoding a L66H substitution) is associated with severe herpesvirus infections in rare patients. Here, we identified a new patient with this CD16 mutation and compared the patient's NK cells to those of the originally reported patient. Patients with the L66H mutation had intact ADCC, but deficient spontaneous NK cell cytotoxicity and decreased surface expression of CD2, a coactivation receptor. Mechanistic studies in a human NK cell line, NK-92, demonstrated that CD16 expression correlated with CD2 surface levels and enabled killing of a melanoma cell line typically resistant to CD16-deficient NK-92 cells. An association between CD16 and CD2 was identified biochemically and at the immunological synapse, which elicited CD16 signaling after CD2 engagement. Stable expression of CD16 L66H in NK-92 cells recapitulated the patient phenotype, abrogating association of CD16 with CD2 as well as CD16 signaling after CD2 ligation. Thus, CD16 serves a role in NK cell-mediated spontaneous cytotoxicity through a specific association with CD2 and represents a potential mechanism underlying a human congenital immunodeficiency.

  3. Tricking the balance: NK cells in anti-cancer immunity.

    PubMed

    Pahl, Jens; Cerwenka, Adelheid

    2017-01-01

    Natural Killer (NK) cells are classically considered innate immune effector cells involved in the first line of defense against infected and malignant cells. More recently, NK cells have emerged to acquire properties of adaptive immunity in response to certain viral infections such as expansion of specific NK cell subsets and long-lasting virus-specific responses to secondary challenges. NK cells distinguish healthy cells from abnormal cells by measuring the net input of activating and inhibitory signals perceived from target cells through NK cell surface receptors. Acquisition of activating ligands in combination with reduced expression of MHC class I molecules on virus-infected and cancer cells activates NK cell cytotoxicity and release of immunostimulatory cytokines like IFN-γ. In the cancer microenvironment however, NK cells become functionally impaired by inhibitory factors produced by immunosuppressive immune cells and cancer cells. Here we review recent progress on the role of NK cells in cancer immunity. We describe regulatory factors of the tumor microenvironment on NK cell function which determine cancer cell destruction or escape from immune recognition. Finally, recent strategies that focus on exploiting NK cell anti-cancer responses for immunotherapeutic approaches are outlined.

  4. Effect of tumor cells and tumor microenvironment on NK-cell function.

    PubMed

    Vitale, Massimo; Cantoni, Claudia; Pietra, Gabriella; Mingari, Maria Cristina; Moretta, Lorenzo

    2014-06-01

    The ability of tumors to manage an immune-mediated attack has been recently included in the "next generation" of cancer hallmarks. In solid tumors, the microenvironment that is generated during the first steps of tumor development has a pivotal role in immune regulation. An intricate net of cross-interactions occurring between tumor components, stromal cells, and resident or recruited immune cells skews the possible acute inflammatory response toward an aberrant ineffective chronic inflammatory status that favors the evasion from the host's defenses. Natural killer (NK) cells have powerful cytotoxic activity, but their activity may be eluded by the tumor microenvironment. Immunosubversion, immunoediting or immunoselection of poorly immunogenic tumor cells and interference with tumor infiltration play a major role in evading NK-cell responses to tumors. Tumor cells, tumor-associated fibroblasts and tumor-induced aberrant immune cells (i.e. tolerogenic or suppressive macrophages, dendritic cells (DCs) and T cells) can interfere with NK-cell activation pathways or the complex receptor array that regulate NK-cell activation and antitumor activity. Thus, the definition of tumor microenvironment-related immunosuppressive factors, along with the identification of new classes of tissue-residing NK-like innate lymphoid cells, represent key issues to design effective NK-cell-based therapies of solid tumors.

  5. IκBζ augments IL-12– and IL-18–mediated IFN-γ production in human NK cells

    PubMed Central

    Kannan, Yashaswini; Yu, Jianhua; Raices, Raquel M.; Seshadri, Sudarshan; Wei, Min; Caligiuri, Michael A.

    2011-01-01

    Interferon-γ (IFN-γ) production by natural killer (NK) cells and cytotoxic lymphocytes is a key component of innate and adaptive immune responses. Because inhibitor of κB-ζ (IκBζ), a Toll-like receptor (TLR)/interleukin-1 receptor (IL-1R) inducible transcription factor, regulates IFN-γ production in KG-1 cells, we tested IκBζ's role in the classic lymphocyte pathway of IL-12/IL-18–induced IFN-γ. Upon stimulation with IL-12/IL-18, monocyte-depleted human peripheral blood lymphocytes expressed the 79-kDa form of IκBζ and released IFN-γ. CD56+ NK cells were shown to be the IκBζ-producing lymphocyte subpopulation, which also released abundant IFN-γ in response to IL-12/IL-18. Importantly, IκBζ was undetectable in CD56− lymphocytes where IFN-γ release was 10-fold lower. In addition, small interfering RNA knockdown of IκBζ suppressed IFN-γ expression in CD56+ cells. The association of IκBζ with the IFN-γ promoter was documented by chromatin immunoprecipitation. IFN-γ promoter activity from IκBζ overexpression was confirmed by luciferase reporter assay. Finally, IκBζ coprecipitated with p65 and p50 NF-κB in NK cells in response to IL-12/IL-18, suggesting that IκBζ's effects on IFN-γ promoter activity are coregulated by NF-κB. These results suggest that IκBζ functions as an important regulator of IFN-γ in human NK cells, further expanding the class of IκBζ-modulated genes. PMID:21224476

  6. CALGB 150905 (Alliance): Rituximab broadens the anti-lymphoma response by activating unlicensed NK cells

    PubMed Central

    Du, Juan; Lopez-Verges, Sandra; Pitcher, Brandelyn N.; Johnson, Jeffrey; Jung, Sin-Ho; Zhou, Lili; Hsu, Katharine; Czuczman, Myron S.; Cheson, Bruce; Kaplan, Lawrence; Lanier, Lewis L.; Venstrom, Jeffrey M.

    2014-01-01

    Natural killer (NK) cells contribute to clinical responses in patients treated with rituximab, but the rules determining NK cell responsiveness to mAb therapies are poorly defined. A deeper understanding of the mechanisms responsible for antibody-dependent cellular cytotoxicity (ADCC) could yield useful biomarkers for predicting clinical responses in patients. Unlicensed NK cells, defined as NK cells lacking expression of an inhibitory KIR for self-HLA class I ligands, are hypo-responsive in steady-state, but are potent effectors in inflammatory conditions. We hypothesized that antitumor antibodies such as rituximab can overcome NK cell dependence on licensing, making unlicensed NK cells important for clinical responses. Here we examined the influences of variations in KIR and HLA class I alleles on in vitro responses to rituximab. We tested the clinical significance in a cohort of follicular lymphoma patients treated with rituximab-containing mAb combinations and show that rituximab triggers responses from all NK cell populations regardless of licensing. Neither IL-2 nor accessory cells are required for activating unlicensed NK cells, but both can augment rituximab-mediated ADCC. Moreover, in 101 follicular lymphoma patients treated with rituximab-containing mAb combinations, a “missing ligand” genotype (predictive of unlicensed NK cells) is associated with higher progression-free survival. Our data suggest that the clinical efficacy of rituximab may be driven, in part, by its ability to broaden the NK cell repertoire to include previously hypo-responsive, unlicensed NK cells. A “missing ligand” KIR and HLA class I genotype may be predictive of this benefit, and useful for personalizing treatment decisions in lymphomas and other tumors. PMID:24958280

  7. Teach Your NK Cells Well.

    PubMed

    Cooper, Megan A

    2016-08-16

    Natural killer cells readily kill target cells, and education ensures tolerance to self. In this issue of Immunity, Boudreau et al. (2016) and Chen et al. (2016) report new mechanisms of human and mouse natural killer cell education by inhibitory and activating receptors.

  8. NK Cells Respond to Haptens by the Activation of Calcium Permeable Plasma Membrane Channels

    PubMed Central

    Grandclément, Camille; Pick, Horst; Vogel, Horst; Held, Werner

    2016-01-01

    Natural Killer (NK) cells mediate innate immunity to infected and transformed cells. Yet, NK cells can also mount hapten-specific recall responses thereby contributing to contact hypersensitivity (CHS). However, since NK cells lack antigen receptors that are used by the adaptive immune system to recognize haptens, it is not clear if NK cells respond directly to haptens and, if so, what mediates these responses. Here we show that among four haptens the two that are known to induce NK cell-dependent CHS trigger the rapid influx of extracellular Ca2+ into NK cells and lymphocyte cell lines. Thus lymphocytes can respond to haptens independent of antigen presentation and antigen receptors. We identify the Ca2+-permeable cation channel TRPC3 as a component of the lymphocyte response to one of these haptens. These data suggest that the response to the second hapten is based on a distinct mechanism, consistent with the capacity of NK cells to discriminate haptens. These findings raise the possibility that antigen-receptor independent activation of immune cells contributes to CHS. PMID:26963818

  9. Models to Study NK Cell Biology and Possible Clinical Application.

    PubMed

    Zamora, Anthony E; Grossenbacher, Steven K; Aguilar, Ethan G; Murphy, William J

    2015-08-03

    Natural killer (NK) cells are large granular lymphocytes of the innate immune system, responsible for direct targeting and killing of both virally infected and transformed cells. NK cells rapidly recognize and respond to abnormal cells in the absence of prior sensitization due to their wide array of germline-encoded inhibitory and activating receptors, which differs from the receptor diversity found in B and T lymphocytes that is due to the use of recombination-activation gene (RAG) enzymes. Although NK cells have traditionally been described as natural killers that provide a first line of defense prior to the induction of adaptive immunity, a more complex view of NK cells is beginning to emerge, indicating they may also function in various immunoregulatory roles and have the capacity to shape adaptive immune responses. With the growing appreciation for the diverse functions of NK cells, and recent technological advancements that allow for a more in-depth understanding of NK cell biology, we can now begin to explore new ways to manipulate NK cells to increase their clinical utility. In this overview unit, we introduce the reader to various aspects of NK cell biology by reviewing topics ranging from NK cell diversity and function, mouse models, and the roles of NK cells in health and disease, to potential clinical applications. © 2015 by John Wiley & Sons, Inc.

  10. Human NK cells in acute myeloid leukaemia patients: analysis of NK cell-activating receptors and their ligands.

    PubMed

    Sanchez-Correa, Beatriz; Morgado, Sara; Gayoso, Inmaculada; Bergua, Juan M; Casado, Javier G; Arcos, Maria Jose; Bengochea, Maria Luisa; Duran, Esther; Solana, Rafael; Tarazona, Raquel

    2011-08-01

    Natural killer (NK) cell activation is strictly regulated to ensure that healthy cells are preserved, but tumour-transformed or virus-infected cells are recognized and eliminated. To carry out this selective killing, NK cells have an ample repertoire of receptors on their surface. Signalling by inhibitory and activating receptors by interaction with their ligands will determine whether the NK cell becomes activated and kills the target cell. Here, we show reduced expression of NKp46, NKp30, DNAM-1, CD244 and CD94/NKG2C activating receptors on NK cells from acute myeloid leukaemia patients. This reduction may be induced by chronic exposure to their ligands on leukaemic blasts. The analysis of ligands for NK cell-activating receptors showed that leukaemic blasts from the majority of patients express ligands for NK cell-activating receptors. DNAM-1 ligands are frequently expressed on blasts, whereas the expression of the NKG2D ligand MICA/B is found in half of the patients and CD48, a ligand for CD244, in only one-fourth of the patients. The decreased expression of NK cell-activating receptors and/or the heterogeneous expression of ligands for major receptors on leukaemic blasts can lead to an inadequate tumour immunosurveillance by NK cells. A better knowledge of the activating receptor repertoire on NK cells and their putative ligands on blasts together with the possibility to modulate their expression will open new possibilities for the use of NK cells in immunotherapy against leukaemia.

  11. Extranodal NK/T cell lymphoma and aggressive NK cell leukaemia: evidence for their origin on CD56+bright CD16-/+dim NK cells.

    PubMed

    Lima, Margarida

    2015-10-01

    Mature natural killer (NK) cell neoplasms are classified by the World Health Organization into extranodal NK/T cell lymphoma, nasal type (ENKTL) and aggressive NK cell leukaemia (ANKL). In order to propose their normal NK cell counterparts, we reviewed the literature on the phenotype of the neoplastic NK cells from five series of patients with ENKTL (n = 411) and seven series of patients with ANKL (n = 114) and compared with that of the normal and activated mature CD56 NK cell subsets. The tumour NK cells usually express brightly the CD56 adhesion molecule and CD94 lectin type killer receptor, and have an activation-related (cytoplasmic CD3ε, CD7, CD45RO, HLA-DR) phenotype; in contrast, CD16 and killer immunoglobulin-like receptors are frequently negative, and CD57 expression is almost never observed. These phenotypic features would suggest that ENKTL and ANKL cells do represent the neoplastic counterpart of the mature CD56 NK cells, which undergo activation and malignant transformation after Epstein-Barr virus infection.

  12. Trypanosoma brucei Co-opts NK Cells to Kill Splenic B2 B Cells

    PubMed Central

    Frenkel, Deborah; Guirnalda, Patrick; Haynes, Carole; Bockstal, Viki; Magez, Stefan; Black, Samuel J.

    2016-01-01

    After infection with T. brucei AnTat 1.1, C57BL/6 mice lost splenic B2 B cells and lymphoid follicles, developed poor parasite-specific antibody responses, lost weight, became anemic and died with fulminating parasitemia within 35 days. In contrast, infected C57BL/6 mice lacking the cytotoxic granule pore-forming protein perforin (Prf1-/-) retained splenic B2 B cells and lymphoid follicles, developed high-titer antibody responses against many trypanosome polypeptides, rapidly suppressed parasitemia and did not develop anemia or lose weight for at least 60 days. Several lines of evidence show that T. brucei infection-induced splenic B cell depletion results from natural killer (NK) cell-mediated cytotoxicity: i) B2 B cells were depleted from the spleens of infected intact, T cell deficient (TCR-/-) and FcγRIIIa deficient (CD16-/-) C57BL/6 mice excluding a requirement for T cells, NKT cell, or antibody-dependent cell-mediated cytotoxicity; ii) administration of NK1.1 specific IgG2a (mAb PK136) but not irrelevant IgG2a (myeloma M9144) prevented infection-induced B cell depletion consistent with a requirement for NK cells; iii) splenic NK cells but not T cells or NKT cells degranulated in infected C57BL/6 mice co-incident with B cell depletion evidenced by increased surface expression of CD107a; iv) purified NK cells from naïve C57BL/6 mice killed purified splenic B cells from T. brucei infected but not uninfected mice in vitro indicating acquisition of an NK cell activating phenotype by the post-infection B cells; v) adoptively transferred C57BL/6 NK cells prevented infection-induced B cell population growth in infected Prf1-/- mice consistent with in vivo B cell killing; vi) degranulated NK cells in infected mice had altered gene and differentiation antigen expression and lost cytotoxic activity consistent with functional exhaustion, but increased in number as infection progressed indicating continued generation. We conclude that NK cells in T. brucei infected mice

  13. Trypanosoma brucei Co-opts NK Cells to Kill Splenic B2 B Cells.

    PubMed

    Frenkel, Deborah; Zhang, Fengqiu; Guirnalda, Patrick; Haynes, Carole; Bockstal, Viki; Radwanska, Magdalena; Magez, Stefan; Black, Samuel J

    2016-07-01

    After infection with T. brucei AnTat 1.1, C57BL/6 mice lost splenic B2 B cells and lymphoid follicles, developed poor parasite-specific antibody responses, lost weight, became anemic and died with fulminating parasitemia within 35 days. In contrast, infected C57BL/6 mice lacking the cytotoxic granule pore-forming protein perforin (Prf1-/-) retained splenic B2 B cells and lymphoid follicles, developed high-titer antibody responses against many trypanosome polypeptides, rapidly suppressed parasitemia and did not develop anemia or lose weight for at least 60 days. Several lines of evidence show that T. brucei infection-induced splenic B cell depletion results from natural killer (NK) cell-mediated cytotoxicity: i) B2 B cells were depleted from the spleens of infected intact, T cell deficient (TCR-/-) and FcγRIIIa deficient (CD16-/-) C57BL/6 mice excluding a requirement for T cells, NKT cell, or antibody-dependent cell-mediated cytotoxicity; ii) administration of NK1.1 specific IgG2a (mAb PK136) but not irrelevant IgG2a (myeloma M9144) prevented infection-induced B cell depletion consistent with a requirement for NK cells; iii) splenic NK cells but not T cells or NKT cells degranulated in infected C57BL/6 mice co-incident with B cell depletion evidenced by increased surface expression of CD107a; iv) purified NK cells from naïve C57BL/6 mice killed purified splenic B cells from T. brucei infected but not uninfected mice in vitro indicating acquisition of an NK cell activating phenotype by the post-infection B cells; v) adoptively transferred C57BL/6 NK cells prevented infection-induced B cell population growth in infected Prf1-/- mice consistent with in vivo B cell killing; vi) degranulated NK cells in infected mice had altered gene and differentiation antigen expression and lost cytotoxic activity consistent with functional exhaustion, but increased in number as infection progressed indicating continued generation. We conclude that NK cells in T. brucei infected mice

  14. Split anergized Natural Killer cells halt inflammation by inducing stem cell differentiation, resistance to NK cell cytotoxicity and prevention of cytokine and chemokine secretion.

    PubMed

    Tseng, Han-Ching; Cacalano, Nicholas; Jewett, Anahid

    2015-04-20

    The mechanism of suppression of NK cytotoxicity in cancer patients is not clearly established. In this paper we provide evidence that anergized NK cells induce differentiation of healthy Dental Pulp Stem Cells (DPSCs) or transformed Oral Squamous Cancer Stem Cells (OSCSCs) resulting in cell growth inhibition, resistance to NK cell-mediated cytotoxicity and prevention of inflammatory mediators secretion. Induction of cytotoxicity resistance in differentiated cells correlated with increased CD54 and MHC class I surface expression and mediated by the combination of IFN-γ and TNF-α since antibodies to both, but not each cytokine alone, was able to inhibit resistance. In contrast, inhibition of cytokine and chemokine release was mediated by IFN-γ since the addition of anti-IFN-γ antibody, and not anti-TNF-α, restored secretion of inflammatory mediators in NK cell cultures with differentiated DPSCs and OSCSCs. There was a gradual and time dependent decrease in MHC class I and CD54 expression which correlated with the restoration of NK cell cytotoxicity, augmentation of cytokine secretion and increased cell growth from days 0-12 post NK removal. Continuous presence of NK cells is required for the maintenance of cell differentiation since the removal of NK cell-mediated function reverses the phenotype and function of differentiated cells to their stem-like cells.

  15. A high-throughput assay of NK cell activity in whole blood and its clinical application

    SciTech Connect

    Lee, Saet-byul; Cha, Junhoe; Kim, Im-kyung; Yoon, Joo Chun; Lee, Hyo Joon; Park, Sang Woo; Cho, Sunjung; Youn, Dong-Ye; Lee, Heyja; Lee, Choong Hwan; Lee, Jae Myun; Lee, Kang Young; Kim, Jongsun

    2014-03-14

    Graphical abstract: - Highlights: • We demonstrated a simple assay of NK cell activity from whole blood. • The measurement of secreted IFN-γ from NK cell enables high-throughput screening. • The NKA assay was validated by clinical results of colorectal cancer patients. - Abstract: Natural killer (NK) cells are lymphocytes of the innate immune system and have the ability to kill tumor cells and virus-infected cells without prior sensitization. Malignant tumors and viruses have developed, however, strategies to suppress NK cells to escape from their responses. Thus, the evaluation of NK cell activity (NKA) could be invaluable to estimate the status and the outcome of cancers, viral infections, and immune-mediated diseases. Established methods that measure NKA, such as {sup 51}Cr release assay and CD107a degranulation assay, may be used to determine NK cell function, but they are complicated and time-consuming because they require isolation of peripheral blood mononuclear cells (PBMC) or NK cells. In some cases these assays require hazardous material such as radioactive isotopes. To overcome these difficulties, we developed a simple assay that uses whole blood instead of PBMC or isolated NK cells. This novel assay is suitable for high-throughput screening and the monitoring of diseases, because it employs serum of ex vivo stimulated whole blood to detect interferon (IFN)-γ secreted from NK cells as an indicator of NKA. After the stimulation of NK cells, the determination of IFNγ concentration in serum samples by enzyme-linked immunosorbent assay (ELISA) provided a swift, uncomplicated, and high-throughput assay of NKA ex vivo. The NKA results microsatellite stable (MSS) colorectal cancer patients was showed significantly lower NKA, 263.6 ± 54.5 pg/mL compared with healthy subjects, 867.5 ± 50.2 pg/mL (p value <0.0001). Therefore, the NKA could be utilized as a supportive diagnostic marker for microsatellite stable (MSS) colorectal cancer.

  16. Natural killer cell (NK) subsets and NK-like T-cell populations in acute myeloid leukemias and myelodysplastic syndromes.

    PubMed

    Aggarwal, N; Swerdlow, S H; TenEyck, S P; Boyiadzis, M; Felgar, R E

    2016-07-01

    The impact of the immune microenvironment on the behavior and therapeutic strategies for hematopoietic and lymphoid neoplasms is being increasingly recognized. Many functional studies of natural killer (NK) cell cytotoxic responses in myelodysplasia (MDS) and acute myeloid leukemia (AML) exist, but with limited data on these lymphocyte proportions and related T-cell subsets. The proportions of these cells and their prognostic implications were therefore investigated in 89 AML, 51 MDS, and 20 control marrows by flow cytometry. The median proportion of NK cells (relative to the total lymphocytes) was lower in AML versus controls (P = 0.01). Among AML, a lower proportion of NK cells predicted better survival, whereas a higher NK cell proportion was associated with the poor prognostic AML category (P = 0.002). NK cell proportions were similar in MDS, MDS subgroups, and control marrows. The relative proportion of the mature NK cell subset (CD56(dim) CD16/57(bright) ) was lower in AML and MDS versus controls (P = 0.006, P = 0.0002, respectively). The proportion of mature NK cells was not a prognostic indicator although fewer were seen in poor prognosis AML. In contrast, a lower proportion of mature NK cells correlated with worse survival in MDS (P = 0.027). A higher proportion of NK-like T-cells (of total lymphoid cells) was found in MDS compared to controls (P = 0.01). A lower proportion of NK-like T-cells predicted better survival in AML but not in MDS. Thus, the proportions of NK, NK-cell subsets, and NK-like T-cells vary in myeloid neoplasms, may potentially impact immunomodulatory therapies, and may impact outcome. © 2016 International Clinical Cytometry Society.

  17. T-cell and NK-cell posttransplantation lymphoproliferative disorders.

    PubMed

    Swerdlow, Steven H

    2007-06-01

    Posttransplantation lymphoproliferative disorders (PTLDs) of T-cell or natural killer (NK)-cell origin are an uncommon heterogeneous group of lymphoid proliferations that fulfill the criteria for one of the T- or NK-cell lymphomas/leukemias. This report summarizes 130 T/NK-cell PTLDs reported in the literature or presented at the Society for Hematopathology/European Association for Haematopathology Workshop on T/NK-cell malignancies. The T/NK-cell PTLDs occur at a median of 66 months following transplantation and are usually extranodal. The most common types reported are peripheral T-cell lymphoma, unspecified, and hepatosplenic T-cell lymphoma. Approximately one third are Epstein-Barr virus (EBV)+. The median survival is 6 months. EBV+ cases have a significantly longer survival than EBV- cases, even when indolent T-cell large granular lymphocytic leukemias are included among the EBV- cases. Many T/NK-cell PTLDs have been treated with chemotherapy, often together with decreased immunosuppression, but there are infrequent patients who have done well without chemotherapy or radiation.

  18. Studying NK cell responses to ectromelia virus infections in mice.

    PubMed

    Fang, Min; Sigal, Luis

    2010-01-01

    Here we describe methods for the in vivo study of antiviral NK cell responses using the mouse Orthopoxvirus ectromelia virus as a model, the agent of mousepox. The methods include those specific for the preparation and use of ectromelia virus such as the production of virus stocks in tissue culture and in live mice, the purification of virus stocks, the titration of virus stocks and virus loads in organs, and the infection of mice. The chapter also includes methods for the specific study of NK cell responses in infected mice such as the preparation of organs (lymph nodes, spleen, and liver) for analysis, the study of NK cell responses by flow cytometry, the adoptive transfer of NK cells, the measurement of NK cell cytolytic activity ex vivo and in vivo, and the determination of NK cell proliferation by bromodeoxyuridine loading or by dilution of carboxyfluorescein diacetate succinimidyl ester (CFSE).

  19. Hepatic stellate cell interferes with NK cell regulation of fibrogenesis via curcumin induced senescence of hepatic stellate cell.

    PubMed

    Jin, Huanhuan; Jia, Yan; Yao, Zhen; Huang, Jingjing; Hao, Meng; Yao, Shunyu; Lian, Naqi; Zhang, Feng; Zhang, Chenxi; Chen, Xingran; Bian, Mianli; Shao, Jiangjuan; Wu, Li; Chen, Anping; Zheng, Shizhong

    2017-05-01

    Hepatic fibrosis, a common scarring response to various forms of chronic liver injury, is a precursor to cirrhosis and liver cancer. During liver fibrosis, hepatic stellate cells (HSCs) initially activate and proliferate, which are responsible for the secretion of extracellular matrix components. However, these cells eventually senesce and are cleared by natural killer (NK) cells. Our previous researches have shown that the natural product curcumin could promote the senescence of activated HSC. In this study, we investigated how NK cells target senescent HSC and assessed the effect of this process on liver fibrosis. We found that senescent HSC induced by curcumin are susceptible to NK cells killing, due to the increased expression of NK cell activating ligand major histocompatibility complex class I chain-related genes A (MICA) and UL16-binding proteins 2 (ULBP2), but not Poliovirus Receptor (PVR). Further studies displayed that the interaction between NK cells and senescent LX2 cells stimulated granule exocytosis. Moreover, the inhibition of granule exocytosis weakened the cytotoxicity of NK cells and promoted the accumulation of senescent LX2 cells. Therefore, these aggregated data indicated that NK cells mediated clearance of senescent LX2 cells and granule exocytosis could play a protective role in the improvement of liver fibrosis.

  20. NK Cells, Tumor Cell Transition, and Tumor Progression in Solid Malignancies: New Hints for NK-Based Immunotherapy?

    PubMed

    Cantoni, Claudia; Huergo-Zapico, Leticia; Parodi, Monica; Pedrazzi, Marco; Mingari, Maria Cristina; Moretta, Alessandro; Sparatore, Bianca; Gonzalez, Segundo; Olive, Daniel; Bottino, Cristina; Castriconi, Roberta; Vitale, Massimo

    2016-01-01

    Several evidences suggest that NK cells can patrol the body and eliminate tumors in their initial phases but may hardly control established solid tumors. Multiple factors, including the transition of tumor cells towards a proinvasive/prometastatic phenotype, the immunosuppressive effect of the tumor microenvironment, and the tumor structure complexity, may account for limited NK cell efficacy. Several putative mechanisms of NK cell suppression have been defined in these last years; conversely, the cross talk between NK cells and tumor cells undergoing different transitional phases remains poorly explored. Nevertheless, recent in vitro studies and immunohistochemical analyses on tumor biopsies suggest that NK cells could not only kill tumor cells but also influence their evolution. Indeed, NK cells may induce tumor cells to change the expression of HLA-I, PD-L1, or NKG2D-L and modulate their susceptibility to the immune response. Moreover, NK cells may be preferentially located in the borders of tumor masses, where, indeed, tumor cells can undergo Epithelial-to-Mesenchymal Transition (EMT) acquiring prometastatic phenotype. Finally, the recently highlighted role of HMGB1 both in EMT and in amplifying the recruitment of NK cells provides further hints on a possible effect of NK cells on tumor progression and fosters new studies on this issue.

  1. NK Cells, Tumor Cell Transition, and Tumor Progression in Solid Malignancies: New Hints for NK-Based Immunotherapy?

    PubMed Central

    Huergo-Zapico, Leticia; Parodi, Monica; Pedrazzi, Marco; Mingari, Maria Cristina; Sparatore, Bianca; Gonzalez, Segundo; Olive, Daniel; Bottino, Cristina

    2016-01-01

    Several evidences suggest that NK cells can patrol the body and eliminate tumors in their initial phases but may hardly control established solid tumors. Multiple factors, including the transition of tumor cells towards a proinvasive/prometastatic phenotype, the immunosuppressive effect of the tumor microenvironment, and the tumor structure complexity, may account for limited NK cell efficacy. Several putative mechanisms of NK cell suppression have been defined in these last years; conversely, the cross talk between NK cells and tumor cells undergoing different transitional phases remains poorly explored. Nevertheless, recent in vitro studies and immunohistochemical analyses on tumor biopsies suggest that NK cells could not only kill tumor cells but also influence their evolution. Indeed, NK cells may induce tumor cells to change the expression of HLA-I, PD-L1, or NKG2D-L and modulate their susceptibility to the immune response. Moreover, NK cells may be preferentially located in the borders of tumor masses, where, indeed, tumor cells can undergo Epithelial-to-Mesenchymal Transition (EMT) acquiring prometastatic phenotype. Finally, the recently highlighted role of HMGB1 both in EMT and in amplifying the recruitment of NK cells provides further hints on a possible effect of NK cells on tumor progression and fosters new studies on this issue. PMID:27294158

  2. The role of natural killer (NK) cells and NK cell receptor polymorphisms in the assessment of HIV-1 neutralization.

    PubMed

    Brown, Bruce K; Wieczorek, Lindsay; Kijak, Gustavo; Lombardi, Kara; Currier, Jeffrey; Wesberry, Maggie; Kappes, John C; Ngauy, Viseth; Marovich, Mary; Michael, Nelson; Ochsenbauer, Christina; Montefiori, David C; Polonis, Victoria R

    2012-01-01

    The importance of innate immune cells in HIV-1 pathogenesis and protection has been highlighted by the role of natural killer (NK) cells in the containment of viral replication. Use of peripheral blood mononuclear cells (PBMC) in immunologic studies provides both HIV-1 target cells (ie. CD4+ T cells), as well as anti-HIV-1 effector cells, such as NK cells. In this study, NK and other immune cell populations were analyzed in HIV-negative donor PBMC for an impact on the anti-HIV activity of polyclonal and monoclonal antibodies. NK cell percentages were significantly higher in donor PBMC that supported lower levels of viral replication. While the percentage of NK cells was not directly associated with neutralization titers, NK cell-depletion significantly diminished the antiviral antibody activity by up to three logs, and polymorphisms in NK killer immunoglobulin receptor (KIR) and FcγRIIIa alleles appear to be associated with this affect. These findings demonstrate that NK cells and NK cell receptor polymorphisms may influence assessment of traditional HIV-1 neutralization in a platform where antibody is continuously present. This format appears to simultaneously assess conventional entry inhibition (neutralization) and non-neutralizing antibody-dependent HIV inhibition, which may provide the opportunity to delineate the dominant antibody function(s) in polyclonal vaccine responses.

  3. The Role of Natural Killer (NK) Cells and NK Cell Receptor Polymorphisms in the Assessment of HIV-1 Neutralization

    PubMed Central

    Brown, Bruce K.; Wieczorek, Lindsay; Kijak, Gustavo; Lombardi, Kara; Currier, Jeffrey; Wesberry, Maggie; Kappes, John C.; Ngauy, Viseth; Marovich, Mary; Michael, Nelson; Ochsenbauer, Christina; Montefiori, David C.; Polonis, Victoria R.

    2012-01-01

    The importance of innate immune cells in HIV-1 pathogenesis and protection has been highlighted by the role of natural killer (NK) cells in the containment of viral replication. Use of peripheral blood mononuclear cells (PBMC) in immunologic studies provides both HIV-1 target cells (ie. CD4+ T cells), as well as anti-HIV-1 effector cells, such as NK cells. In this study, NK and other immune cell populations were analyzed in HIV-negative donor PBMC for an impact on the anti-HIV activity of polyclonal and monoclonal antibodies. NK cell percentages were significantly higher in donor PBMC that supported lower levels of viral replication. While the percentage of NK cells was not directly associated with neutralization titers, NK cell-depletion significantly diminished the antiviral antibody activity by up to three logs, and polymorphisms in NK killer immunoglobulin receptor (KIR) and FcγRIIIa alleles appear to be associated with this affect. These findings demonstrate that NK cells and NK cell receptor polymorphisms may influence assessment of traditional HIV-1 neutralization in a platform where antibody is continuously present. This format appears to simultaneously assess conventional entry inhibition (neutralization) and non-neutralizing antibody-dependent HIV inhibition, which may provide the opportunity to delineate the dominant antibody function(s) in polyclonal vaccine responses. PMID:22509241

  4. Role for coronin 1 in mouse NK cell function.

    PubMed

    Tchang, Vincent Sam Yong; Stiess, Michael; Siegmund, Kerstin; Karrer, Urs; Pieters, Jean

    2017-02-01

    Coronin 1, a member of the evolutionary conserved WD repeat protein family of coronin proteins is expressed in all leukocytes, but a role for coronin 1 in natural killer (NK) cell homeostasis and function remains unclear. Here, we have analyzed the number and functionality of NK cells in the presence and absence of coronin 1. In coronin 1-deficient mice, absolute NK cell numbers and phenotype were comparable to wild type mice in blood, spleen and liver. Following in vitro stimulation of the activating NK cell receptors NK1.1, NKp46, Ly49D and NKG2D, coronin 1-deficient NK cells were functional with respect to interferon-γ production, degranulation and intracellular Ca(2+) mobilization. Also, both wild type as well as coronin 1-deficient NK cells showed comparable cytotoxic activity. Furthermore, activation and functionality of NK cells following Vesicular Stomatitis Virus (VSV) infection was similar between wild type and coronin 1-deficient mice. Taken together these data suggest that coronin 1 is dispensable for mouse NK cell homeostasis and function.

  5. Effects of prolactin and cortisol on natural killer (NK) cell surface expression and function of human natural cytotoxicity receptors (NKp46, NKp44 and NKp30).

    PubMed

    Mavoungou, E; Bouyou-Akotet, M K; Kremsner, P G

    2005-02-01

    The surface density of the triggering receptors (e.g. NKp46 and NKp30) responsible for natural killer (NK) cell-mediated cytotoxicity determines the ability of NK cells to kill susceptible target cells. In this study, we show that prolactin up-regulates and cortisol down-regulates the surface expression of NKp46 and NKp30. The prolactin-mediated activation and the cortisol-mediated inhibition of natural cytotoxicity receptor (NCR) surface expression reflects gene regulation at the transcriptional level. NKp46 and NKp30 are the major receptors involved in the NK-mediated killing of K562, a human chronic myelogenous leukaemia cell line. Accordingly, the prolactin dramatically increased the NK-mediated killing of the K562 cell line, whereas cortisol abolished this activity. Our data suggest a mechanism by which prolactin activates the lytic function of NK cells, and cortisol inhibits the NK-mediated attack.

  6. Anti-ovarian tumor response of donor peripheral blood mononuclear cells is due to infiltrating cytotoxic NK cells

    PubMed Central

    Pandey, Veethika; Oyer, Jeremiah L.; Igarashi, Robert Y.; Gitto, Sarah B.; Copik, Alicja J.; Altomare, Deborah A.

    2016-01-01

    Treatment of ovarian cancer, a leading cause of gynecological malignancy, has good initial efficacy with surgery and platinum/taxane-based chemotherapy, but poor long-term survival in patients. Inferior long-term prognosis is attributed to intraperitoneal spreading, relapse and ineffective alternate therapies. Adoptive cell therapy is promising for tumor remission, although logistical concerns impede widespread implementation. In this study, healthy PBMCs were used to examine the immune response in a mouse model with human ovarian cancer, where natural killer (NK) cells were found to be the effector cells that elicited an anti-tumor response. Presence of tumor was found to stimulate NK cell expansion in mice treated intraperitoneally with PBMC+Interleukin-2 (IL-2), as compared to no expansion in non-tumor-bearing mice given the same treatment. PBMC+IL-2 treated mice exhibiting NK cell expansion had complete tumor remission. To validate NK cell mediated anti-tumor response, the intratumoral presence of NK cells and their cytotoxicity was confirmed by immunohistochemistry and granzyme activity of NK cells recovered from the tumor. Collectively, this study highlights the significance of NK cell-cytotoxic response to tumor, which may be attributed to interacting immune cell types in the PBMC population, as opposed to clinically used isolated NK cells showing lack of anti-tumor efficacy in ovarian cancer patients. PMID:26802025

  7. Anti-ovarian tumor response of donor peripheral blood mononuclear cells is due to infiltrating cytotoxic NK cells.

    PubMed

    Pandey, Veethika; Oyer, Jeremiah L; Igarashi, Robert Y; Gitto, Sarah B; Copik, Alicja J; Altomare, Deborah A

    2016-02-09

    Treatment of ovarian cancer, a leading cause of gynecological malignancy, has good initial efficacy with surgery and platinum/taxane-based chemotherapy, but poor long-term survival in patients. Inferior long-term prognosis is attributed to intraperitoneal spreading, relapse and ineffective alternate therapies. Adoptive cell therapy is promising for tumor remission, although logistical concerns impede widespread implementation. In this study, healthy PBMCs were used to examine the immune response in a mouse model with human ovarian cancer, where natural killer (NK) cells were found to be the effector cells that elicited an anti-tumor response. Presence of tumor was found to stimulate NK cell expansion in mice treated intraperitoneally with PBMC+Interleukin-2 (IL-2), as compared to no expansion in non-tumor-bearing mice given the same treatment. PBMC+IL-2 treated mice exhibiting NK cell expansion had complete tumor remission. To validate NK cell mediated anti-tumor response, the intratumoral presence of NK cells and their cytotoxicity was confirmed by immunohistochemistry and granzyme activity of NK cells recovered from the tumor. Collectively, this study highlights the significance of NK cell-cytotoxic response to tumor, which may be attributed to interacting immune cell types in the PBMC population, as opposed to clinically used isolated NK cells showing lack of anti-tumor efficacy in ovarian cancer patients.

  8. High NKG2A expression contributes to NK cell exhaustion and predicts a poor prognosis of patients with liver cancer.

    PubMed

    Sun, Cheng; Xu, Jing; Huang, Qiang; Huang, Mei; Wen, Hao; Zhang, Chuanshan; Wang, Jinyu; Song, Jiaxi; Zheng, Meijuan; Sun, Haoyu; Wei, Haiming; Xiao, Weihua; Sun, Rui; Tian, Zhigang

    2017-01-01

    Background and Aims: As the predominant lymphocyte subset in the liver, natural killer (NK) cells have been shown to be highly associated with the outcomes of patients with chronic hepatitis B virus infection (CHB) and hepatocellular carcinoma (HCC). Previously, we reported that NKG2A, a checkpoint candidate, mediates human and murine NK cell dysfunction in CHB. However, NK cell exhaustion and, particularly, the level of NKG2A expression within liver tumors have not been reported. Methods: In this study, we analyzed NKG2A expression and the related dysfunction of NK cells located in intra- or peritumor regions of liver tissue samples from 207 HCC patients, in addition to analyzing disease outcomes. Results: The expression of NKG2A in NK cells and the NKG2A ligand, HLA-E, in intratumor HCC tissues was observed to be increased. These NK cells, and particularly CD56(dim) NK cells, with higher NKG2A expression showed features of functional exhaustion and were associated with a poor prognosis. The increase in NKG2A expression might be induced by IL-10, which was present at a high level in the plasma of HCC patients. Blocking IL-10 could specifically inhibit NKG2A expression in NK cells. Conclusions: These findings indicate that NKG2A expression is influenced by factors from cancer nests and contributes to NK cell exhaustion, suggesting that NKG2A blockade has the potential to restore immunity against liver tumors by reversing NK cell exhaustion.

  9. Interleukin-15 Dendritic Cells Harness NK Cell Cytotoxic Effector Function in a Contact- and IL-15-Dependent Manner.

    PubMed

    Anguille, Sébastien; Van Acker, Heleen H; Van den Bergh, Johan; Willemen, Yannick; Goossens, Herman; Van Tendeloo, Viggo F; Smits, Evelien L; Berneman, Zwi N; Lion, Eva

    2015-01-01

    The contribution of natural killer (NK) cells to the treatment efficacy of dendritic cell (DC)-based cancer vaccines is being increasingly recognized. Much current efforts to optimize this form of immunotherapy are therefore geared towards harnessing the NK cell-stimulatory ability of DCs. In this study, we investigated whether generation of human monocyte-derived DCs with interleukin (IL)-15 followed by activation with a Toll-like receptor stimulus endows these DCs, commonly referred to as "IL-15 DCs", with the capacity to stimulate NK cells. In a head-to-head comparison with "IL-4 DCs" used routinely for clinical studies, IL-15 DCs were found to induce a more activated, cytotoxic effector phenotype in NK cells, in particular in the CD56bright NK cell subset. With the exception of GM-CSF, no significant enhancement of cytokine/chemokine secretion was observed following co-culture of NK cells with IL-15 DCs. IL-15 DCs, but not IL-4 DCs, promoted NK cell tumoricidal activity towards both NK-sensitive and NK-resistant targets. This effect was found to require cell-to-cell contact and to be mediated by DC surface-bound IL-15. This study shows that DCs can express a membrane-bound form of IL-15 through which they enhance NK cell cytotoxic function. The observed lack of membrane-bound IL-15 on "gold-standard" IL-4 DCs and their consequent inability to effectively promote NK cell cytotoxicity may have important implications for the future design of DC-based cancer vaccine studies.

  10. In Vivo Efficacy of Umbilical Cord Blood Stem Cell-Derived NK Cells in the Treatment of Metastatic Colorectal Cancer

    PubMed Central

    Veluchamy, John P.; Lopez-Lastra, Silvia; Spanholtz, Jan; Bohme, Fenna; Kok, Nina; Heideman, Daniëlle A. M.; Verheul, Henk M. W.; Di Santo, James P.; de Gruijl, Tanja D.; van der Vliet, Hans J.

    2017-01-01

    Therapeutic monoclonal antibodies against the epidermal growth factor receptor (EGFR) act by inhibiting EGFR downstream signaling and by eliciting a natural killer (NK) cell-mediated antitumor response. The IgG1 mAb cetuximab has been used for treatment of RASwt metastatic colorectal cancer (mCRC) patients, showing limited efficacy. In the present study, we address the potential of adoptive NK cell therapy to overcome these limitations investigating two allogeneic NK cell products, i.e., allogeneic activated peripheral blood NK cells (A-PBNK) and umbilical cord blood stem cell-derived NK cells (UCB-NK). While cetuximab monotherapy was not effective against EGFR− RASwt, EGFR+ RASmut, and EGFR+ BRAFmut cells, A-PBNK were able to initiate lysis of EGFR+ colon cancer cells irrespective of RAS or BRAF status. Cytotoxic effects of A-PBNK (but not UCB-NK) were further potentiated significantly by coating EGFR+ colon cancer cells with cetuximab. Of note, a significantly higher cytotoxicity was induced by UCB-NK in EGFR−RASwt (42 ± 8 versus 67 ± 7%), EGFR+ RASmut (20 ± 2 versus 37 ± 6%), and EGFR+ BRAFmut (23 ± 3 versus 43 ± 7%) colon cancer cells compared to A-PBNK and equaled the cytotoxic efficacy of the combination of A-PBNK and cetuximab. The antitumor efficacy of UCB-NK cells against cetuximab-resistant human EGFR+ RASmut colon cancer cells was further confirmed in an in vivo preclinical mouse model where UCB-NK showed enhanced antitumor cytotoxicity against colon cancer independent of EGFR and RAS status. As UCB-NK have been proven safe in a recently conducted phase I clinical trial in acute myeloid leukemia, a fast translation into clinical proof of concept for mCRC could be considered. PMID:28220124

  11. Identification of Human Memory-Like NK Cells.

    PubMed

    Kovalenko, Elena I; Streltsova, Maria A; Kanevskiy, Leonid M; Erokhina, Sophia A; Telford, William G

    2017-01-05

    Our understanding of NK biology is increased dramatically, a product of improved flow-cytometric techniques for analyzing these cells. NK cells undergo significant changes in repertoire during differentiation. A repeating stimulus, such as a cytomegalovirus infection, may result in accumulation of certain types of highly differentiated NK cells designated as memory-like, or adaptive NK cells. Adaptive NK cells are capable of rapid expansion and effective response to the recall stimulus. These cells differ significantly from conventional NK cells both functionally and phenotypically. Here we describe an approach for identification and analysis of adaptive NK cells in human peripheral blood. CD57-positive cells with high expression of activating-receptor NKG2C, increased expression of KIR receptors, lack of co-expression with inhibitory receptor NKG2A, and decreased expression of activating receptor NCR3 (NKp30) all characterize this cell type. The flow-cytometric method described below can identify this NK cell subset on a relatively simple flow cytometer. © 2017 by John Wiley & Sons, Inc.

  12. Cryptococcus neoformans Directly Stimulates Perforin Production and Rearms NK Cells for Enhanced Anticryptococcal Microbicidal Activity▿

    PubMed Central

    Marr, Kaleb J.; Jones, Gareth J.; Zheng, Chunfu; Huston, Shaunna M.; Timm-McCann, Martina; Islam, Anowara; Berenger, Byron M.; Ma, Ling Ling; Wiseman, Jeremy C. D.; Mody, Christopher H.

    2009-01-01

    NK cells, in addition to possessing antitumor and antiviral activity, exhibit perforin-dependent microbicidal activity against the opportunistic pathogen Cryptococcus neoformans. However, the factors controlling this response, particularly whether the pathogen itself provides an activation or rearming signal, are largely unknown. The current studies were performed to determine whether exposure to this fungus alters subsequent NK cell anticryptococcal activity. NK cells lost perforin and mobilized lysosome-associated membrane protein 1 to the cell surface following incubation with the fungus, indicating that degranulation had occurred. Despite a reduced perforin content during killing, NK cells acquired an enhanced ability to kill C. neoformans, as demonstrated using auxotrophs that allowed independent assessment of the killing of two strains. De novo protein synthesis was required for optimal killing; however, there was no evidence that a soluble factor contributed to the enhanced anticryptococcal activity. Exposure of NK cells to C. neoformans caused the cells to rearm, as demonstrated by increased perforin mRNA levels and enhanced loss of perforin when transcription was blocked. Degranulation alone was insufficient to provide the activation signal as NK cells lost anticryptococcal activity following treatment with strontium chloride. However, NK cells regained the activity upon prolonged exposure to C. neoformans, which is consistent with activation by the microbe. The enhanced cytotoxicity did not extend to tumor killing since NK cells exposed to C. neoformans failed to kill NK-sensitive tumor targets (K562 cells). These studies demonstrate that there is contact-mediated microbe-specific rearming and activation of microbicidal activity that are necessary for optimal killing of C. neoformans. PMID:19307209

  13. Use of allogeneic NK cells for cancer immunotherapy

    PubMed Central

    Geller, Melissa A; Miller, Jeffrey S

    2012-01-01

    Controversy exists as to the role that the immune system plays in cancer therapy. While the immune system has been proposed to scavenge the body to prevent microscopic transformation from forming cancer, it has been difficult to mount its potential of shrinking established tumors. NK cells are components of the innate immune system. They can recognize targets without prior sensitization, making them ideal candidates to manipulate for therapeutic use against cancer. Initially, autologous NK cells were directed against tumors but it was realized that NK cells that recognize self cells are inhibited. More encouraging advances have been made with allogeneic NK cell therapy in clinical trials to overcome this limitation. In this article, we present developments in NK cell adoptive immunotherapy for hematologic and solid tumor malignancies. PMID:22091681

  14. Microfluidic-based, live-cell analysis allows assessment of NK-cell migration in response to crosstalk with dendritic cells.

    PubMed

    Mahmood, Sajid; Nandagopal, Saravanan; Sow, Ibrahim; Lin, Francis; Kung, Sam K P

    2014-09-01

    Migration and localization of NK cells into peripheral tissues are tightly regulated under normal and pathological conditions. The physiological importance of NK cell-DC crosstalk has been well documented. However, the ways in which DCs regulate the migratory properties of NK cells (such as chemotaxis, chemokinesis, chemo-repulsion) are not fully defined in vitro. Here, we employed a microfluidic platform to examine, at the single-cell level, C57BL/6 NK-cell migrations in a stable chemical gradient. We observed that soluble factors released by the immature and LPS-activated mature DCs induced a high level of chemotactic movement of IL-2-activated NK cells in vitro. We confirmed these findings in a standard trans-well migration assay, and identified CXCR3 as a key receptor on the NK cells that mediated the migration. More interestingly, we revealed a novel function of granulocyte macrophage colony-stimulating factor in repulsing NK-cell migrations. The future uses of such microfluidic device in the systematic evaluations of NK-cell migratory responses in NK cell-DC crosstalk will provide new insights into the development of DC-based NK-cell therapies against tumor and infections.

  15. Biallelic IRF8 Mutations Causing NK Cell Deficiency.

    PubMed

    López-Soto, Alejandro; Lorenzo-Herrero, Seila; Gonzalez, Segundo

    2017-03-01

    Human primary immunodeficiencies result in an exacerbated susceptibility to contracting infectious diseases. Recent work by Mace et al., published in the Journal of Clinical Investigation, unveils a novel genetic cause for the development of familial natural killer (NK) cell deficiency: a biallelic compound heterozygous mutation in IRF8, which leads to impaired NK cell development and cytotoxic activity.

  16. Prostaglandin E2 exerts the proapoptotic and antiproliferative effects on bovine NK cells.

    PubMed

    Maślanka, Tomasz; Chrostowska, Małgorzata; Otrocka-Domagała, Iwona; Snarska, Anna; Mikiewicz, Mateusz; Zuśka-Prot, Monika; Jasiecka, Agnieszka; Ziółkowski, Hubert; Markiewicz, Włodzimierz; Jaroszewski, Jerzy J

    2016-08-01

    The aim of this research was to determine whether prostaglandin E2 (PGE2) affects bovine NK cells in respect of their counts, apoptosis and proliferation, and if it does, then which of the PGE2 receptor (EP) subtype(s) mediate(s) these effects. We here report that long-term, but not short-term, exposure of bovine peripheral blood mononuclear cells to PGE2 at 10(-5)M, 10(-6)M and 10(-7)M, but not at 10(-8)M, caused a significant increase in the percentage of early apoptotic cells among NK cell subset. Moreover, PGE2 at 10(-5)M and 10(-6)M, but not at 10(-7)M and 10(-8)M, induced a considerable decrease in the absolute count of NK cells. The magnitude of these effects increased with an increasing concentration of PGE2. The blockade of EP1, EP2, EP3 and EP4 receptors did not prevent the PGE2-induced apoptosis and depletion of NK cells. The results suggest that the proapoptotic effect of PGE2 is secondary in character and the induction of this effect is not mediated through EP receptors. Furthermore, the studies demonstrated that PGE2 at 10(-5)M and 10(-6)M, but not at 10(-7)M and 10(-8)M, highly significantly reduced the percentage of proliferating NK cells. The EP1, EP1/2 and EP3 receptor antagonists were unable to block this effect significantly, whereas the selective blockade of EP4 receptors prevented the PGE2-induced inhibition of NK cells proliferation. These results indicate that PGE2 at certain concentrations may impair the proliferation of NK cells and this effect is mediated via the EP4 receptor.

  17. Both mature KIR+ and immature KIR- NK cells control pediatric acute B-cell precursor leukemia in NOD.Cg-Prkdcscid IL2rgtmWjl/Sz mice.

    PubMed

    Kübler, Ayline; Woiterski, Jeanette; Witte, Kai-Erik; Bühring, Hans-Jörg; Hartwig, Udo F; Ebinger, Martin; Oevermann, Lena; Mezger, Markus; Herr, Wolfgang; Lang, Peter; Handgretinger, Rupert; Münz, Christian; André, Maya C

    2014-12-18

    Therapeutic natural killer (NK)-cell-mediated alloreactivity toward acute myeloid leukemia has largely been attributed to mismatches between killer immunoglobulin-like receptors (KIRs) on NK cells and their ligands, HLA class I molecules, on target cells. While adult acute B-cell precursor leukemia (BCP-ALL) appears to be resistant to NK-cell-mediated lysis, recent data indicate that pediatric BCP-ALL might yet be a target of NK cells. In this study, we demonstrate in a donor-patient-specific NOD.Cg-Prkdc(scid) IL2rg(tmWjl)/Sz (NSG) xenotransplantation model that NK cells mediate considerable alloreactivity toward pediatric BCP-ALL in vivo. Notably, both adoptively transferred mature KIR(+) NK cells and immature KIR(-) NK cells arising early posttransplantation in humanized NSG mice exerted substantial antileukemic activity. Low-dose and long-term treatment of humanized NSG mice with the DNA-demethylating agent 5-aza-cytidine distinctly enhanced the antitumor response, interestingly without inducing common inhibitory KIR expression but rather by promoting the differentiation of various NK-cell precursor subsets. Collectively, these data indicate that the future design of innovative therapy protocols should consider further exploitation of NK-cell-mediated immune responses for poor prognosis pediatric BCP-ALL patients.

  18. An autosomal dominant locus, Nka, mapping to the Ly-49 region of a rat natural killer (NK) gene complex, controls NK cell lysis of allogeneic lymphocytes

    PubMed Central

    1996-01-01

    Natural Killer (NK) cells can recognize and kill MHC-incompatible normal bone marrow-derived cells. Presently characterized MHC-binding receptors on NK cells, including the Ly-49 family in the mouse, transmit inhibitory signals upon binding to cognate class I MHC ligands. Here we study in vivo NK-mediated lysis of normal allogeneic lymphocytes in crosses between alloreactivity-competent PVG rats and alloreactivity-deficient DA rats. NK cells from both strains are able to lyse standard tumor targets. We identify an autosomal dominant locus, Nka, that controls NK-mediated alloreactivity. Individuals carrying the dominant PVG allele in single dose were fully competent in eliminating allogeneic target cells, suggesting that Nka encodes or regulates a gene product inducing or activating alloreactivity. By linkage analysis and pulsed field gel electrophoresis, a natural killer gene complex (NKC) on rat chromosome 4 is described that contains the rat NKR-P1 and Ly-49 multigene families plus a rat NKG2D homologue. Nka maps within the NKC, together with the most telomeric Ly-49 family members, but separate from NKG2D and the NKR-P1 family. The Nka-encoded response, moreover, correlates with the expression of transcripts for Ly-49 receptors in NK cell populations, as Northern blot analysis demonstrated low expression of Ly-49 genes in DA NK cells, in contrast to high expression in alloreactivity-competent PVG, (DA X PVG)F1, and PVG.1AVI NK cells. The low Ly-49 expression in DA is not induced by MHC haplotype, as demonstrated by high expression of Ly-49 in the DA MHC- congenic PVG.1AVI strain. Finally, we have cloned and characterized the first four members of the rat Ly-49 gene family. Their cytoplasmic domains demonstrate substantial heterogeneity, consistent with the hypothesis that different Ly-49 family members may subserve different signaling functions. PMID:8642329

  19. Human Parthenogenetic Embryonic Stem Cell–Derived Neural Stem Cells Express HLA-G and Show Unique Resistance to NK Cell–Mediated Killing

    PubMed Central

    Schmitt, Jessica; Eckardt, Sigrid; Schlegel, Paul G; Sirén, Anna-Leena; Bruttel, Valentin S; McLaughlin, K John; Wischhusen, Jörg; Müller, Albrecht M

    2015-01-01

    Parent-of-origin imprints have been implicated in the regulation of neural differentiation and brain development. Previously we have shown that, despite the lack of a paternal genome, human parthenogenetic (PG) embryonic stem cells (hESCs) can form proliferating neural stem cells (NSCs) that are capable of differentiation into physiologically functional neurons while maintaining allele-specific expression of imprinted genes. Since biparental (“normal”) hESC–derived NSCs (N NSCs) are targeted by immune cells, we characterized the immunogenicity of PG NSCs. Flow cytometry and immunocytochemistry revealed that both N NSCs and PG NSCs exhibited surface expression of human leukocyte antigen (HLA) class I but not HLA-DR molecules. Functional analyses using an in vitro mixed lymphocyte reaction assay resulted in less proliferation of peripheral blood mononuclear cells (PBMC) with PG compared with N NSCs. In addition, natural killer (NK) cells cytolyzed PG less than N NSCs. At a molecular level, expression analyses of immune regulatory factors revealed higher HLA-G levels in PG compared with N NSCs. In line with this finding, MIR152, which represses HLA-G expression, is less transcribed in PG compared with N cells. Blockage of HLA-G receptors ILT2 and KIR2DL4 on natural killer cell leukemia (NKL) cells increased cytolysis of PG NSCs. Together this indicates that PG NSCs have unique immunological properties due to elevated HLA-G expression. PMID:25811991

  20. Highly efficient IL-21 and feeder cell-driven ex vivo expansion of human NK cells with therapeutic activity in a xenograft mouse model of melanoma.

    PubMed

    Granzin, Markus; Stojanovic, Ana; Miller, Matthias; Childs, Richard; Huppert, Volker; Cerwenka, Adelheid

    2016-01-01

    Natural killer (NK) cells are promising antitumor effector cells, but the generation of sufficient NK cell numbers for adoptive immunotherapy remains challenging. Therefore, we developed a method for highly efficient ex vivo expansion of human NK cells. Ex vivo expansion of NK cells in medium containing IL-2 and irradiated clinical-grade feeder cells (EBV-LCL) induced a 22-fold NK cell expansion after one week that was significantly increased to 53-fold by IL-21. Repeated stimulation with irradiated EBV-LCL and IL-2 and addition of IL-21 at the initiation of the culture allowed sustained NK cell proliferation with 10(11)-fold NK cell expansion after 6 weeks. Compared to naive NK cells, expanded NK cells upregulated TRAIL, NKG2D, and DNAM-1, had superior cytotoxicity against tumor cell lines in vitro and produced more IFNγ and TNF-α upon PMA/Iono stimulation. Most importantly, adoptive transfer of NK cells expanded using feeder cells, IL-2 and IL-21 led to significant inhibition of tumor growth in a melanoma xenograft mouse model, which was greater than with NK cells activated with IL-2 alone. Intriguingly, adoptively transferred NK cells maintained their enhanced production of IFNγ and TNF-α upon ex vivo restimulation, although they rapidly lost their capacity to degranulate and mediate tumor cytotoxicity after the in vivo transfer. In conclusion, we developed a protocol for ex vivo NK cell expansion that results in outstanding cell yields. The expanded NK cells possess potent antitumor activity in vitro and in vivo and could be utilized at high numbers for adoptive immunotherapy in the clinic.

  1. Isolation and (111)In-Oxine Labeling of Murine NK Cells for Assessment of Cell Trafficking in Orthotopic Lung Tumor Model.

    PubMed

    Malviya, Gaurav; Nayak, Tapan; Gerdes, Christian; Dierckx, Rudi A J O; Signore, Alberto; de Vries, Erik F J

    2016-04-04

    A noninvasive in vivo imaging method for NK cell trafficking is essential to gain further understanding of the pathogenesis of NK cell mediated immune response to the novel cancer treatment strategies, and to discover the homing sites and physiological distribution of NK cells. Although human NK cells can be labeled for in vivo imaging, little is known about the murine NK cell labeling and its application in animal models. This study describes the isolation and ex vivo radiolabeling of murine NK cells for the evaluation of cell trafficking in an orthotopic model of human lung cancer in mice. Scid-Tg(FCGR3A)Blt transgenic SCID mice were used to isolate NK cells from mouse splenocytes using the CD49b (DX5) MicroBeads positive selection method. The purity and viability of the isolated NK cells were confirmed by FACS analysis. Different labeling buffers and incubation times were evaluated to optimize (111)In-oxine labeling conditions. Functionality of the radiolabeled NK cell was assessed by (51)Cr-release assay. We evaluated physiological distribution of (111)In-oxine labeled murine NK cells in normal SCID mice and biodistribution in irradiated and nonirradiated SCID mice with orthotopic A549 human lung tumor lesions. Imaging findings were confirmed by histology. Results showed that incubation with 0.011 MBq of (111)In-oxine per million murine NK cells in PBS (pH 7.4) for 20 min is the best condition that provides optimum labeling efficiency without affecting cell viability and functionality. Physiological distribution in normal SCID mice demonstrated NK cells homing mainly in the spleen, while (111)In released from NK cells was excreted via kidneys into urine. Biodistribution studies demonstrated a higher lung uptake in orthotopic lung tumor-bearing mice than control mice. In irradiated mice, lung tumor uptake of radiolabeled murine NK cells decreased between 24 h and 72 h postinjection (p.i.), which was accompanied by tumor regression, while in nonirradiated mice

  2. Features of Memory-Like and PD-1(+) Human NK Cell Subsets.

    PubMed

    Della Chiesa, Mariella; Pesce, Silvia; Muccio, Letizia; Carlomagno, Simona; Sivori, Simona; Moretta, Alessandro; Marcenaro, Emanuela

    2016-01-01

    Human NK cells are distinguished into CD56(bright)CD16(-) cells and CD56(dim)CD16(+) cells. These two subsets are conventionally associated with differential functional outcomes and are heterogeneous with respect to the expression of KIR and CD94/NKG2 heterodimers that represent the two major types of HLA-class I-specific receptors. Recent studies indicated that immature CD56(bright) NK cells, homogeneously expressing the inhibitory CD94/NKG2A receptor, are precursors of CD56(dim) NK cells that, in turn, during their process of differentiation, lose expression of CD94/NKG2A and subsequentially acquire inhibitory KIRs and LIR-1. The terminally differentiated phenotype of CD56(dim) cells is marked by the expression of the CD57 molecule that is associated with poor responsiveness to cytokine stimulation, but retained cytolytic capacity. Remarkably, this NKG2A(-)KIR(+)LIR-1(+)CD57(+)CD56(dim) NK cell subset when derived from individuals previously exposed to pathogens, such as human cytomegalovirus (HCMV), may contain "memory-like" NK cells. These cells are generally characterized by an upregulation of the activating receptor CD94/NKG2C and a downregulation of the inhibitory receptor Siglec-7. The "memory-like" NK cells are persistent over time and display some hallmarks of adaptive immunity, i.e., clonal expansion, more effective antitumor and antiviral immune responses, longevity, as well as given epigenetic modifications. Interestingly, unknown cofactors associated with HCMV infection may induce the onset of a recently identified fully mature NK cell subset, characterized by marked downregulation of the activating receptors NKp30 and NKp46 and by the unexpected expression of the inhibitory PD-1 receptor. This phenotype correlates with an impaired antitumor NK cell activity that can be partially restored by antibody-mediated disruption of PD-1/PD-L interaction.

  3. Impaired NK Cell Activation and Chemotaxis toward Dendritic Cells Exposed to Complement-Opsonized HIV-1.

    PubMed

    Ellegård, Rada; Crisci, Elisa; Andersson, Jonas; Shankar, Esaki M; Nyström, Sofia; Hinkula, Jorma; Larsson, Marie

    2015-08-15

    Mucosa resident dendritic cells (DCs) may represent one of the first immune cells that HIV-1 encounters during sexual transmission. The virions in body fluids can be opsonized with complement factors because of HIV-mediated triggering of the complement cascade, and this appears to influence numerous aspects of the immune defense targeting the virus. One key attribute of host defense is the ability to attract immune cells to the site of infection. In this study, we investigated whether the opsonization of HIV with complement (C-HIV) or a mixture of complement and Abs (CI-HIV) affected the cytokine and chemokine responses generated by DCs, as well as their ability to attract other immune cells. We found that the expression levels of CXCL8, CXCL10, CCL3, and CCL17 were lowered after exposure to either C-HIV or CI-HIV relative to free HIV (F-HIV). DCs exposed to F-HIV induced higher cell migration, consisting mainly of NK cells, compared with opsonized virus, and the chemotaxis of NK cells was dependent on CCL3 and CXCL10. NK cell exposure to supernatants derived from HIV-exposed DCs showed that F-HIV induced phenotypic activation (e.g., increased levels of TIM3, CD69, and CD25) and effector function (e.g., production of IFNγ and killing of target cells) in NK cells, whereas C-HIV and CI-HIV did not. The impairment of NK cell recruitment by DCs exposed to complement-opsonized HIV and the lack of NK activation may contribute to the failure of innate immune responses to control HIV at the site of initial mucosa infection.

  4. Immunoregulatory Role of NK Cells in Tissue Inflammation and Regeneration

    PubMed Central

    Tosello-Trampont, Annie; Surette, Fionna A.; Ewald, Sarah E.; Hahn, Young S.

    2017-01-01

    NK cells represent an important first line of defense against viral infection and cancer and are also involved in tissue homeostasis. Studies of NK cell activation in the last decade have revealed that they are able to respond to the inflammatory stimuli evoked by tissue damage and contribute to both progression and resolution of diseases. Exacerbation of the inflammatory response through interactions between immune effector cells facilitates the progression of non-alcoholic fatty liver disease (NAFLD) into steatosis, cirrhosis, and hepatocellular carcinoma (HCC). When hepatic damage is incurred, macrophage activation is crucial for initiating cross talk with neighboring cells present in the liver, including hepatocytes and NK cells, and the importance of this interaction in shaping the immune response in liver disease is increasingly recognized. Inflicted structural damage can be in part regenerated via the process of self-limiting fibrosis, though persistent hepatic damage will lead to chronic fibrosis and loss of tissue organization and function. The cytotoxic activity of NK cells plays an important role in inducing hepatic stellate cell apoptosis and thus curtailing the progression of fibrosis. Alternatively, in some diseases, such as HCC, NK cells may become dysregulated, promoting an immunosuppressive state where tumors are able to escape immune surveillance. This review describes the current understanding of the contributions of NK cells to tissue inflammation and metabolic liver diseases and the ongoing effort to develop therapeutics that target the immunoregulatory function of NK cells. PMID:28373874

  5. Involvement of autophagy in NK cell development and function.

    PubMed

    López-Soto, Alejandro; Bravo-San Pedro, José Manuel; Kroemer, Guido; Galluzzi, Lorenzo; Gonzalez, Segundo

    2017-03-04

    Natural killer (NK) cells are the prototypical members of the recently identified family of innate lymphoid cells (ILCs). Thanks to their cytotoxic and secretory functions, NK cells play a key role in the immune response to cells experiencing various forms of stress, including viral infection and malignant transformation. Autophagy is a highly conserved network of degradative pathways that participate in the maintenance of cellular and organismal homeostasis as they promote adaptation to adverse microenvironmental conditions. The relevance of autophagy in the development and functionality of cellular components of the adaptive immune system is well established. Conversely, whether autophagy also plays an important role in the biology of ILC populations such as NK cells has long remained elusive. Recent experimental evidence shows that ablating Atg5 (autophagy-related 5, an essential component of the autophagic machinery) in NK cells and other specific ILC populations results in progressive mitochondrial damage, reactive oxygen species (ROS) overgeneration, and regulated cell death, hence interrupting ILC development. Moreover, disrupting the interaction of ATG7 with phosphorylated FOXO1 (forkhead box O1) in the cytosol of immature NK cells prevents autophagic responses that are essential for NK cell maturation. These findings suggest that activating autophagy may support the maturation of NK cells and other ILCs that manifest antiviral and anticancer activity.

  6. Human NK cells maintain licensing status and are subject to killer immunoglobulin-like receptor (KIR) and KIR-ligand inhibition following ex vivo expansion.

    PubMed

    Wang, Wei; Erbe, Amy K; Alderson, Kory A; Phillips, Emily; Gallenberger, Mikayla; Gan, Jacek; Campana, Dario; Hank, Jacquelyn A; Sondel, Paul M

    2016-09-01

    Infusion of allogeneic NK cells is a potential immunotherapy for both hematopoietic malignancies and solid tumors. Interactions between killer immunoglobulin-like receptors (KIR) on human NK cells and KIR-ligands on tumor cells influence the magnitude of NK function. To obtain sufficient numbers of activated NK cells for infusion, one potent method uses cells from the K562 human erythroleukemia line that have been transfected to express activating 41BB ligand (41BBL) and membrane-bound interleukin 15 (mbIL15). The functional importance of KIRs on ex vivo expanded NK cells has not been studied in detail. We found that after a 12-day co-culture with K562-mbIL15-41BBL cells, expanded NK cells maintained inhibition specificity and prior in vivo licensing status determined by KIR/KIR-ligand interactions. Addition of an anti-CD20 antibody (rituximab) induced NK-mediated antibody-dependent cellular cytotoxicity and augmented killing of CD20+ target cells. However, partial inhibition induced by KIR/KIR-ligand interactions persisted. Finally, we found that extended co-cultures of NK cells with stimulatory cells transduced to express various KIR-ligands modified both the inhibitory and activating KIR repertoires of the expanded NK cell product. These studies demonstrate that the licensing interactions known to occur during NK ontogeny also influence NK cell function following NK expansion ex vivo with HLA-null stimulatory cells.

  7. The role of NK cells in HIV-1 protection: autologous, allogeneic or both?

    PubMed

    Hens, Jef; Jennes, Wim; Kestens, Luc

    2016-01-01

    Natural killer (NK) cells specialize in killing virally infected- or tumor cells and are part of the innate immune system. The activational state of NK cells is determined by the balance of incoming activating and inhibitory signals mediated by receptor-ligand binding with the target cell. These receptor-ligand bonds mainly consist of the killer immunoglobulin-like receptors (KIR), which are expressed at the cell surface of NK cells, and their ligands: the highly variable human leukocyte antigen -class I molecules (HLA). Absence of an inhibitory receptor-ligand bond lowers the NK cell activation threshold, whereas an activating receptor-ligand bond stimulates the cell, potentially overcoming this threshold and triggering NK cell activation. NK cells influence the course of infection as well as the acquisition of HIV-1. Several lines of evidence relate the activating NK cell receptor KIR3DS1, in the presence or absence of its putative ligand HLA-Bw4, with slower disease progression as well as resistance to HIV-1 infection. Overall, resistance to HIV-1 infection predominantly correlates with activating KIR/HLA profiles, consisting of e.g. activating KIRs, group B haplotypes, or inhibitory KIRs in absence of their ligands. Such a conclusion is less evident for studies of HIV-1 disease progression, with studies reporting beneficial as well as detrimental effects of activating KIR/HLA genotypes. It is likely that KIR/HLA association studies are complicated by the complexity of the KIR and HLA loci and their mutual interactions, as well as by additional factors like route of HIV exposure, immune activation, presence of co-infections, and the effect of anti-HIV-1 antibodies. One newly discovered NK cell activation pathway associated with resistance to HIV-1 infection involves the presence of an iKIR/HLA mismatch between partners. The absence of such an iKIR/HLA bond renders donor-derived allogeneic HIV-1 infected cells vulnerable to NK cell responses during HIV-1

  8. Anti-metastatic effects of viral and non-viral mediated Nk4 delivery to tumours

    PubMed Central

    Buhles, Alexandra; Collins, Sara A; van Pijkeren, Jan P; Rajendran, Simon; Miles, Michelle; O'Sullivan, Gerald C; O'Hanlon, Deirdre M; Tangney, Mark

    2009-01-01

    The most common cause of death of cancer sufferers is through the occurrence of metastases. The metastatic behaviour of tumour cells is regulated by extracellular growth factors such as hepatocyte growth factor (HGF), a ligand for the c-Met receptor tyrosine kinase, and aberrant expression/activation of the c-Met receptor is closely associated with metastatic progression. Nk4 (also known as Interleukin (IL)32b) is a competitive antagonist of the HGF c-Met system and inhibits c-Met signalling and tumour metastasis. Nk4 has an additional anti-angiogenic activity independent of its HGF-antagonist function. Angiogenesis-inhibitory as well as cancer-specific apoptosis inducing effects make the Nk4 sequence an attractive candidate for gene therapy of cancer. This study investigates the inhibition of tumour metasasis by gene therapy mediated production of Nk4 by the primary tumour. Optimal delivery of anti-cancer genes is vital in order to achieve the highest therapeutic responses. Non-viral plasmid delivery methods have the advantage of safety and ease of production, providing immediate transgene expression, albeit short-lived in most tumours. Sustained presence of anti-angiogenic molecules is preferable with anti-angiogenic therapies, and the long-term expression mediated by Adeno-associated Virus (AAV) might represent a more appropriate delivery in this respect. However, the incubation time required by AAV vectors to reach appropriate gene expression levels hampers efficacy in many fast-growing murine tumour models. Here, we describe murine trials assessing the effects of Nk4 on the spontaneously metastatic Lewis Lung Carcinoma (LLC) model when delivered to primary tumour via plasmid lipofection or AAV2 vector. Intratumoural AAV-Nk4 administration produced the highest therapeutic response with significant reduction in both primary tumour growth and incidence of lung metastases. Plasmid-mediated therapy also significantly reduced metastatic growth, but with moderate

  9. Human NK Cell Diversity in Viral Infection: Ramifications of Ramification

    PubMed Central

    Strauss-Albee, Dara M.; Blish, Catherine A.

    2016-01-01

    Natural killer (NK) cells are a unique lymphocyte lineage with remarkable agility in the rapid destruction of virus-infected cells. They are also the most poorly understood class of lymphocyte. A spectrum of activating and inhibitory receptors at the NK cell surface leads to an unusual and difficult-to-study mechanism of cellular recognition, as well as a very high capacity for diversity at the single-cell level. Here, we review the evidence for the role of NK cells in the earliest stage of human viral infection, and in its prevention. We argue that single-cell diversity is a logical evolutionary adaptation for their position in the immune response and contributes to their ability to kill virus-infected cells. Finally, we look to the future, where emerging single-cell technologies will enable a new generation of rigorous and clinically relevant studies on NK cells accounting for all of their unique and diverse characteristics. PMID:26973646

  10. Protective role of NK1.1+ cells in experimental Staphylococcus aureus arthritis

    PubMed Central

    NILSSON, N; BREMELL, T; TARKOWSKI, A; CARLSTEN, H

    1999-01-01

    In a model of Staphylococcus aureus-induced septic arthritis in C57Bl/6 mice we investigated the role of natural killer (NK) cells in the development of disease. Depletion of NK1.1+ cells was achieved by repeated injections of the PK136 antibody, whereas control mice received an irrelevant monoclonal antibody, O1C5.B2. Both groups of mice then received injections intravenously with 2 × 107 live S. aureus LS-1 secreting toxic shock syndrome toxin-1 (TSST-1). The mice were evaluated for 16 days with regard to weight, mortality and arthritis. Nine days after bacterial injection, 9/19 mice depleted of NK cells had developed arthritis compared with 1/17 in the control group (P = 0.01). The experiment was repeated twice with the same outcome. NK cell-depleted and control mice displayed the same degree of histopathological signs of arthritis at day 16. Depletion of NK cells did not affect uptake of bacteria by phagocytic cells in vitro, or bacterial clearance in vivo. In NK cell-depleted mice there was a tendency to increased levels of antibodies to TSST-1, whereas total immunoglobulin levels were similar to those in controls. NK cell depletion of non-infected mice did not affect the magnitude of inflammatory response during the T cell-dependent cutaneous DTH reaction to oxazolone, or during granulocyte-mediated inflammation. However, specific antibody responses to oxazolone were greatly increased in depleted animals. In conclusion, our study demonstrates that NK cells protect against arthritis during S. aureus infection. This outcome does not seem to be due to an influence on bacterial clearance, but could be due to an interaction with the host anti-inflammatory mechanisms. PMID:10403917

  11. In vivo IFN-γ secretion by NK cells in response to Salmonella typhimurium requires NLRC4 inflammasomes.

    PubMed

    Kupz, Andreas; Curtiss, Roy; Bedoui, Sammy; Strugnell, Richard A

    2014-01-01

    Natural killer (NK) cells are a critical part of the innate immune defense against viral infections and for the control of tumors. Much less is known about how NK cells contribute to anti-bacterial immunity. NK cell-produced interferon gamma (IFN-γ) contributes to the control of early exponential replication of bacterial pathogens, however the regulation of these events remains poorly resolved. Using a mouse model of invasive Salmonellosis, here we report that the activation of the intracellular danger sensor NLRC4 by Salmonella-derived flagellin within CD11c+ cells regulates early IFN-γ secretion by NK cells through the provision of interleukin 18 (IL-18), independently of Toll-like receptor (TLR)-signaling. Although IL18-signalling deficient NK cells improved host protection during S. Typhimurium infection, this increased resistance was inferior to that provided by wild-type NK cells. These findings suggest that although NLRC4 inflammasome-driven secretion of IL18 serves as a potent activator of NK cell mediated IFN-γ secretion, IL18-independent NK cell-mediated mechanisms of IFN-γ secretion contribute to in vivo control of Salmonella replication.

  12. Resveratrol Induces Cell Cycle Arrest and Apoptosis in Malignant NK Cells via JAK2/STAT3 Pathway Inhibition

    PubMed Central

    Quoc Trung, Ly; Espinoza, J. Luis; Takami, Akiyoshi; Nakao, Shinji

    2013-01-01

    Natural killer (NK) cell malignancies, particularly aggressive NK cell leukaemias and lymphomas, have poor prognoses. Although recent regimens with L-asparaginase substantially improved outcomes, novel therapeutic approaches are still needed to enhance clinical response. Resveratrol, a naturally occurring polyphenol, has been extensively studied for its anti-inflammatory, cardioprotective and anti-cancer activities. In this study, we investigated the potential anti-tumour activities of resveratrol against the NK cell lines KHYG-1, NKL, NK-92 and NK-YS. Resveratrol induced robust G0/G1 cell cycle arrest, significantly suppressed cell proliferation and induced apoptosis in a dose- and time-dependent manner for all four cell lines. In addition, resveratrol suppressed constitutively active STAT3 in all the cell lines and inhibited JAK2 phosphorylation but had no effect on other upstream mediators of STAT3 activation, such as PTEN, TYK2, and JAK1. Resveratrol also induced downregulation of the anti-apoptotic proteins MCL1 and survivin, two downstream effectors of the STAT3 pathway. Finally, resveratrol induced synergistic effect on the apoptotic and antiproliferative activities of L-asparaginase against KHYG-1, NKL and NK-92 cells. These results suggest that resveratrol may have therapeutic potential against NK cell malignancies. Furthermore, our finding that resveratrol is a bonafide JAK2 inhibitor extends its potential benefits to other diseases with dysregulated JAK2 signaling. PMID:23372833

  13. Cord Blood Mononuclear Cells Have a Potential to Produce NK Cells Using IL2Rg Cytokines

    PubMed Central

    Khaziri, Nahid; Mohammadi, Momeneh; Aliyari, Zeinab; Soleimani Rad, Jafar; Tayefi Nasrabadi, Hamid; Nozad Charoudeh, Hojjatollah

    2016-01-01

    Purpose: Although bone marrow represents the main site for NK cell development and also distinct thymic-dependentNK cell pathway was identified, the cytokines effect on the NK cell generation from cord blood is unclear. Studies were identified the role of cytokines in the regulation of bone marrow and thymic NK cells. Previous studies reported that IL15 are critical for bone marrow dependent and IL7 is important for thymic NK cells. It is remain unclear the cytokines influence on the expantion of NK cells in cord blood mononuclear cells. Methods: We evaluated cultured cord blood mononuclear cells suplememnted with combinations of cytokines using FACS in distinct time points. In this study, we presented the role of IL2, IL7 and IL15 as members of the common gamma receptor -chain (Il2rg) on the expansion NK cells from cord blood cells. Results: By investigating cord blood mononuclear cells in vitro , we demonstrated that IL2 and IL15 are important for expansion of NK cells. IL2 in comparision with IL15 has more influences in NK cell expansion. In contrast IL-7 is dispensable for NK cell generation in cord blood. Conclusion: Thus,IL-2Rg cytokines play complementary roles and are indispensable for homeostasis of NK cell development in cord blood. Probably these cytokines could help to use NK beneficials in engrafment of transplanted cells and Anti tumor activity of NK cells. PMID:27123412

  14. Sera from patients with colon, breast and lung cancer induce resistance to lysis mediated by NK cytotoxic factors (NKCF).

    PubMed Central

    Marubayashi, M.; Solana, R.; Ramirez, R.; Aranda, E.; Galan, F.; Peña, J.

    1991-01-01

    Natural killer (NK) cells are involved in the antitumoral immunologic mechanism. These cells act through the release of cytotoxic molecules defined as NK cytotoxic factors (NKCF). Inhibitory factors of NK and NKCF mediated lysis have been described in in vitro assays. This study evaluates the induction of resistance to NKCF cytotoxicity by sera from 27 patients with colon, breast and lung cancer. Addition of these sera to the cytolytic assay where K562 cells and concentrated NKCF were used, induced resistance to NKCF mediated cytotoxicity in 21 cases (77%). The sera from the group with metastasis blocked NKCF lysis more markedly than the group with local tumours. However, no differences were observed when the groups with colon, breast and lung cancers were compared. This blocking effect was not found to be related to gamma interferon (IFN) levels. In a previous study, we described a tumour factor (NK-RIF) produced by human cell lines derived from metastatic adenocarcinomas. This factor blocked lysis of tumour target cells by NK cells. Consequently, it is proposed that the release of similar tumour factors with a capacity to induce resistance to NKCF may be involved in tumour growth and metastatic spreading in in vivo. PMID:1906292

  15. Generation and preclinical characterization of an NKp80-Fc fusion protein for redirected cytolysis of natural killer (NK) cells against leukemia.

    PubMed

    Deng, Gang; Zheng, Xiaodong; Zhou, Jing; Wei, Haiming; Tian, Zhigang; Sun, Rui

    2015-09-11

    The capacity of natural killer (NK) cells to mediate Fc receptor-dependent effector functions, such as antibody-dependent cellular cytotoxicity (ADCC), largely contributes to their clinical application. Given that activation-induced C-type lectin (AICL), an identified ligand for the NK-activating receptor NKp80, is frequently highly expressed on leukemia cells, the lack of therapeutic AICL-specific antibodies limits clinical application. Here we explore a strategy to reinforce NK anti-leukemia reactivity by combining targeting AICL-expressing leukemia cells with the induction of NK cell ADCC using NKp80-Fc fusion proteins. The NKp80-Fc fusion protein we generated bound specifically to leukemia cells in an AICL-specific manner. Cell binding assays between NK and leukemia cells showed that NKp80-Fc significantly increased NK target cell conjugation. In functional analyses, treatment with NKp80-Fc clearly induced the ADCC effect of NK cells. NKp80-Fc not only promoted NK-mediated leukemia cell apoptosis in the early stage of cell conjugation but also enhanced NK cell degranulation and cytotoxicity activity in the late stage. The bifunctional NKp80-Fc could redirect NK cells toward leukemia cells and triggered NK cell killing in vitro. Moreover, NKp80-Fc enhanced the lysis of NK cells against tumors in leukemia xenograft non-obese diabetic/severe combined immunodeficiency mice. Taken together, our results demonstrate that NKp80-Fc potently amplifies NK cell anti-leukemia effects in vitro and in vivo through induction of the NK cell ADCC effect. This method could potentially be useful for molecular targeted therapy, and the fusion proteins may be a promising drug for immunotherapy of leukemia.

  16. Polarization of NK cell cytoskeleton upon conjugation with sensitive target cells.

    PubMed

    Carpén, O; Virtanen, I; Lehto, V P; Saksela, E

    1983-12-01

    We studied the cytoskeletal changes in natural killer (NK) cells during conjugate formation, i.e., when NK cells make contact with sensitive vs resistant target cells. F-actin and vinculin were seen to polarize at the contact sites upon conjugation with sensitive K562 cells, whereas in conjugates with resistant Raji target cells such an orientation was an infrequent finding. Myosin and two other cytoskeletal proteins, spectrin and vimentin, on the other hand, showed a random distribution in conjugating NK cells regardless of the target cell type. Hence the cytoskeletal redistribution associated with conjugation seems to be different from the receptor capping phenomenon, which is accompanied by clustering of actin, myosin, vimentin, and spectrin. On the basis of these results it seems probable that the lytic conjugate formation in NK-mediated cytotoxicity is associated with the formation of a specific type of junction that involves actin and vinculin. This cytoskeletal reorganization precedes and could be a prerequisite for the polarization of the cellular secretory apparatus and may be functionally responsible for the required cytokinetic movements.

  17. TGF-β inhibits the activation and functions of NK cells by repressing the mTOR pathway.

    PubMed

    Viel, Sébastien; Marçais, Antoine; Guimaraes, Fernando Souza-Fonseca; Loftus, Roisin; Rabilloud, Jessica; Grau, Morgan; Degouve, Sophie; Djebali, Sophia; Sanlaville, Amélien; Charrier, Emily; Bienvenu, Jacques; Marie, Julien C; Caux, Christophe; Marvel, Jacqueline; Town, Liam; Huntington, Nicholas D; Bartholin, Laurent; Finlay, David; Smyth, Mark J; Walzer, Thierry

    2016-02-16

    Transforming growth factor-β (TGF-β) is a major immunosuppressive cytokine that maintains immune homeostasis and prevents autoimmunity through its antiproliferative and anti-inflammatory properties in various immune cell types. We provide genetic, pharmacologic, and biochemical evidence that a critical target of TGF-β signaling in mouse and human natural killer (NK) cells is the serine and threonine kinase mTOR (mammalian target of rapamycin). Treatment of mouse or human NK cells with TGF-β in vitro blocked interleukin-15 (IL-15)-induced activation of mTOR. TGF-β and the mTOR inhibitor rapamycin both reduced the metabolic activity and proliferation of NK cells and reduced the abundances of various NK cell receptors and the cytotoxic activity of NK cells. In vivo, constitutive TGF-β signaling or depletion of mTOR arrested NK cell development, whereas deletion of the TGF-β receptor subunit TGF-βRII enhanced mTOR activity and the cytotoxic activity of the NK cells in response to IL-15. Suppression of TGF-β signaling in NK cells did not affect either NK cell development or homeostasis; however, it enhanced the ability of NK cells to limit metastases in two different tumor models in mice. Together, these results suggest that the kinase mTOR is a crucial signaling integrator of pro- and anti-inflammatory cytokines in NK cells. Moreover, we propose that boosting the metabolic activity of antitumor lymphocytes could be an effective strategy to promote immune-mediated tumor suppression.

  18. Bacterial Manipulation of NK Cell Regulatory Activity Increases Susceptibility to Listeria monocytogenes Infection

    PubMed Central

    Guthrie, Brandon S.; Schmidt, Rebecca L.; Jamieson, Amanda; Merkel, Patricia; Knight, Vijaya; Cole, Caroline M.; Raulet, David H.; Lenz, Laurel L.

    2016-01-01

    Natural killer (NK) cells produce interferon (IFN)-γ and thus have been suggested to promote type I immunity during bacterial infections. Yet, Listeria monocytogenes (Lm) and some other pathogens encode proteins that cause increased NK cell activation. Here, we show that stimulation of NK cell activation increases susceptibility during Lm infection despite and independent from robust NK cell production of IFNγ. The increased susceptibility correlated with IL-10 production by responding NK cells. NK cells produced IL-10 as their IFNγ production waned and the Lm virulence protein p60 promoted induction of IL-10 production by mouse and human NK cells. NK cells consequently exerted regulatory effects to suppress accumulation and activation of inflammatory myeloid cells. Our results reveal new dimensions of the role played by NK cells during Lm infection and demonstrate the ability of this bacterial pathogen to exploit the induction of regulatory NK cell activity to increase host susceptibility. PMID:27295349

  19. Interferon-γ-induced activation of JAK1 and JAK2 suppresses tumor cell susceptibility to NK cells through upregulation of PD-L1 expression.

    PubMed

    Bellucci, Roberto; Martin, Allison; Bommarito, Davide; Wang, Kathy; Hansen, Steen H; Freeman, Gordon J; Ritz, Jerome

    2015-06-01

    Inhibition of JAK1 or JAK2 in human tumor cells was previously shown to increase susceptibility of these cells to NK cell lysis. In the present study, we examined the cellular mechanisms that mediate this effect in hematopoietic tumor cell lines and primary tumor cells. Incubation of tumor cells with supernatant from activated NK cells or interferon-gamma (IFNγ)-induced activation of pSTAT1 and increased expression of PD-L1 without altering expression of other activating or inhibitory NK cell ligands. These functional effects were blocked by chemical JAK inhibition or shRNAs targeting JAK1, JAK2 or STAT1. Inhibition of IFNγ signaling also prevented the upregulation of PD-L1 and blocking PD-L1 resulted in increased tumor lysis by NK cells. These results show that NK cell activation and secretion of IFNγ results in activation of JAK1, JAK2 and STAT1 in tumor cells, resulting in rapid up-regulation of PD-L1 expression. Increased expression of PD-L1 results in increased resistance to NK cell lysis. Blockade of JAK pathway activation prevents increased PD-L1 expression resulting in increased susceptibility of tumor cells to NK cell activity. These observations suggest that JAK pathway inhibitors as well as PD-1 and PD-L1 antibodies may work synergistically with other immune therapies by preventing IFN-induced inhibition of NK cell-mediated tumor cell lysis.

  20. Functional Assessment of NK and LAK Cells Following Space Flight

    NASA Technical Reports Server (NTRS)

    Kaur, Indreshpal; Pierson, Duane L.; Paloski, W. H. (Technical Monitor)

    1999-01-01

    Space flight associated stress alters some aspects of the human immune response. In this study, we determined the effects of 10 days aboard the Space Shuttle on the cytotoxic activity of NK and LAK cells. PBMCs were collected from 10-ml blood specimens from 5 astronauts 10 days before launch, immediately after landing, and again at 3 days after landing and stored at -80 C. All PBMCs were thawed simultaneously, and the cytotoxic activities of NK and LAK cells were measured by a 4 hour Cr-51 release assay. K562 cells were used to assess NK cell cytotoxicity. Following 4 days of IL-2 activation, the LAK cell cytotoxic activity was determined using K562 cells and Daudi cells as the target cells. NK cell cytotoxicity decreased at landing (p<.05) in 3/5 astronauts, and recovered to preflight levels by 3 days following landing; NK cell cytotoxicity was increased (p=0.1) in the remaining 2 astronauts at landing. In 4/5 astronauts, LAK cytotoxic activity was decreased at landing against K562 cells (p = 0.13) and Daudi cells (p = 0.08). Phenotyping of PBMC's and LAK cells showed alterations in some surface markers and adhesion molecules (CD11b, CD11c, CD11a, CD16, L-selectin, and CD3).

  1. Melanoma-associated fibroblasts modulate NK cell phenotype and antitumor cytotoxicity

    PubMed Central

    Balsamo, Mirna; Scordamaglia, Francesca; Pietra, Gabriella; Manzini, Claudia; Cantoni, Claudia; Boitano, Monica; Queirolo, Paola; Vermi, William; Facchetti, Fabio; Moretta, Alessandro; Moretta, Lorenzo; Mingari, Maria Cristina; Vitale, Massimo

    2009-01-01

    Although the role of the tumor microenvironment in the process of cancer progression has been extensively investigated, the contribution of different stromal components to tumor growth and/or evasion from immune surveillance is still only partially defined. In this study we analyzed fibroblasts derived from metastatic melanomas and provide evidence for their strong immunosuppressive activity. In coculture experiments, melanoma-derived fibroblasts sharply interfered with NK cell functions including cytotoxicity and cytokine production. Thus, both the IL-2-induced up-regulation of the surface expression of NKp44, NKp30, and DNAM-1 triggering receptors and the acquisition of cytolytic granules were inhibited in NK cells. This resulted in an impairment of the NK cell-mediated killing of melanoma target cells. Transwell cocultures and the use of specific inhibitors suggested that cell-to-cell contact was required for inducing DNAM-1 modulation. In contrast, modulation of NKp44 and NKp30 was due to PGE2 released by fibroblasts during coculture. Normal skin fibroblasts could also partially affect NK cell phenotype and function. However, the inhibitory effect of tumor-derived fibroblasts was far stronger and directly correlated with their ability to produce PGE2 either constitutively or upon induction by NK cells. PMID:19934056

  2. Beyond NK cells: the expanding universe of innate lymphoid cells.

    PubMed

    Cella, Marina; Miller, Hannah; Song, Christina

    2014-01-01

    For a long time, natural killer (NK) cells were thought to be the only innate immune lymphoid population capable of responding to invading pathogens under the influence of changing environmental cues. In the last few years, an increasing amount of evidence has shown that a number of different innate lymphoid cell (ILC) populations found at mucosal sites rapidly respond to locally produced cytokines in order to establish or maintain homeostasis. These ILC populations closely mirror the phenotype of adaptive T helper subsets in their repertoire of secreted soluble factors. Early in the immune response, ILCs are responsible for setting the stage to mount an adaptive T cell response that is appropriate for the incoming insult. Here, we review the diversity of ILC subsets and discuss similarities and differences between ILCs and NK cells in function and key transcriptional factors required for their development.

  3. α1-Antitrypsin modifies general NK cell interactions with dendritic cells and specific interactions with islet β-cells in favor of protection from autoimmune diabetes.

    PubMed

    Guttman, Ofer; Yossef, Rami; Freixo-Lima, Gabriella; Rider, Peleg; Porgador, Angel; Lewis, Eli C

    2014-10-13

    The autoimmune destruction of pancreatic β-cells is the hallmark of type 1 diabetes (T1D). Failure of anti-CD3 antibodies to provide long-lasting reversal of T1D and the expression of an NK cell ligand on β-cells suggest that NK cells play a role in disease pathogenesis. Indeed, killing of β-cells by NK cells has been shown to occur, mediated by activation of the NK cell activating receptor, NKp46. α1-antitrypsin (AAT), an anti-inflammatory and immunomodulatory glycoprotein, protects β-cells from injurious immune responses and is currently evaluated as a therapeutic for recent onset T1D. While isolated T lymphocytes are not inhibited by AAT, dendritic cells (DCs) become tolerogenic in its presence and other innate immune cells become less inflammatory. Yet a comprehensive profile of NK cell responses in the presence of AAT has yet to be described. In the present study, we demonstrate that AAT significantly reduces NK cell degranulation against β-cells, albeit in the whole animal and not in isolated NK cell cultures. AAT-treated mice, and not isolated cultured β-cells, exhibited a marked reduction in NKp46 ligand levels on β-cells. In related experiments, AAT-treated DCs exhibited reduced inducible DC-expressed IL-15 levels and evoked a weaker NK cell response. NK cell depletion in a T1D mouse model resulted in improved β-cell function and survival, similar to the effects observed by AAT treatment alone; nonetheless, the two approaches were non-synergistic. Our data suggest that AAT is a selective immunomodulator that retains pivotal NK cell responses, while diverting their activities away from islet β-cells. This article is protected by copyright. All rights reserved.

  4. Selection and expansion of natural killer cells for NK cell-based immunotherapy.

    PubMed

    Becker, Petra S A; Suck, Garnet; Nowakowska, Paulina; Ullrich, Evelyn; Seifried, Erhard; Bader, Peter; Tonn, Torsten; Seidl, Christian

    2016-04-01

    Natural killer (NK) cells have been used in several clinical trials as adaptive immunotherapy. The low numbers of these cells in peripheral blood mononuclear cells (PBMC) have resulted in various approaches to preferentially expand primary NK cells from PBMC. While some clinical trials have used the addition of interleukin 2 (IL-2) to co-stimulate the expansion of purified NK cells from allogeneic donors, recent studies have shown promising results in achieving in vitro expansion of NK cells to large numbers for adoptive immunotherapy. NK cell expansion requires multiple cell signals for survival, proliferation and activation. Thus, expansion strategies have been focused either to substitute these factors using autologous feeder cells or to use genetically modified allogeneic feeder cells. Recent developments in the clinical use of genetically modified NK cell lines with chimeric antigen receptors, the development of expansion protocols for the clinical use of NK cell from human embryonic stem cells and induced pluripotent stem cells are challenging improvements for NK cell-based immunotherapy. Transfer of several of these protocols to clinical-grade production of NK cells necessitates adaptation of good manufacturing practice conditions, and the development of freezing conditions to establish NK cell stocks will require some effort and, however, should enhance the therapeutic options of NK cells in clinical medicine.

  5. Recruitment and Activation of Natural Killer (Nk) Cells in Vivo Determined by the Target Cell Phenotype

    PubMed Central

    Glas, Rickard; Franksson, Lars; Une, Clas; Eloranta, Maija-Leena; Öhlén, Claes; Örn, Anders; Kärre, Klas

    2000-01-01

    Natural killer (NK) cells can spontaneously lyse certain virally infected and transformed cells. However, early in immune responses NK cells are further activated and recruited to tissue sites where they perform effector functions. This process is dependent on cytokines, but it is unclear if it is regulated by NK cell recognition of susceptible target cells. We show here that infiltration of activated NK cells into the peritoneal cavity in response to tumor cells is controlled by the tumor major histocompatibility complex (MHC) class I phenotype. Tumor cells lacking appropriate MHC class I expression induced NK cell infiltration, cytotoxic activation, and induction of transcription of interferon γ in NK cells. The induction of these responses was inhibited by restoration of tumor cell MHC class I expression. The NK cells responding to MHC class I–deficient tumor cells were ∼10 times as active as endogenous NK cells on a per cell basis. Although these effector cells showed a typical NK specificity in that they preferentially killed MHC class I–deficient cells, this specificity was even more distinct during induction of the intraperitoneal response. Observations are discussed in relation to a possible adaptive component of the NK response, i.e., recruitment/activation in response to challenges that only NK cells are able to neutralize. PMID:10620611

  6. Comparative analysis of NK-cell receptor expression and function across primate species

    PubMed Central

    Ugolotti, Elisabetta; De Maria, Andrea

    2010-01-01

    Natural killer (NK) cells are lymphoid effectors that are involved in the innate immune surveillance against infected and/or tumor cells. Their function is under the fine-tuning control of cell surface receptors that display either inhibitory or activating function and in healthy condition, mediate self-tolerance. It is known that inhibitory receptors are characterized by clonal and stochastic distribution and are extremely sensible to any modification, downregulation or loss of MHC class I surface expression that are induced in autologous cells upon viral infection or cancer transformation. This alteration of the MHC class I expression weakens the strength of the inhibitory receptor-induced interaction, thus resulting in a prompt triggering of NK cell function, which ends up in the inhibition of tumor progression and proliferation of pathogen-infected cells. Thus, the inhibitory function of NK cells is only one face of the coin, since NK-cell activation is controlled by different arrays of activating receptors that finally are involved in the induction of cytolysis and/or cytokine release. Interestingly, the inhibitory NK-cell receptors that are involved in dampening NK cell-mediated responses evolved during speciation in different, often structurally unrelated surface-expressed molecules, all using a conserved signaling pathway. In detail, during evolution, the inhibitory receptors that assure the recognition of MHC class I molecules, originate in, at least, three different ways. This ended up in multigene families showing marked structural divergences that coevolved in a convergent way with the availability of appropriate MHC ligand molecules. PMID:21487512

  7. Listeria monocytogenes infection differentially affects expression of ligands for NK cells and NK cell responses, depending on the cell type infected.

    PubMed

    Shegarfi, Hamid; Rolstad, Bent; Kane, Kevin P; Nestvold, Janne

    2016-04-22

    The pivotal role of NK cells in viral infection is extensively studied, whereas the role of NK cells in bacterial infection has been poorly investigated. Here, we have examined how Listeria monocytogenes (LM) affects expression of ligands for NK cell receptors and subsequent NK cell responses, depending on the type of cell infected. LM infected rat cell lines derived from different tissues were coincubated with splenic NK cells, and NK cell proliferation and IFN-γ production were measured. In addition, expression of ligands for the NK cell receptors Ly49 and NK cell receptor protein 1 (NKR-P1), MHC class I and C-type lectin-related molecules, respectively, was assessed. Infected pleural R2 cells, but not epithelium-derived colon carcinoma cell line CC531 cells, induced proliferation of NK cells. Reporter cells expressing the inhibitory NKR-P1G receptor or the activating NKR-P1F receptor were less stimulated under incubation with infected CC531 cells versus uninfected CC531 controls, suggesting that the ligand(s) in question were down-regulated by infection. Conversely, LM infection of R2 cells did not affect reporter cell stimulation compared with uninfected R2 controls. We characterized a rat monocyte cell line, termed RmW cells. In contrast to LM infected R2 cells that up-regulate MHC class I molecules, RmW cells displayed unchanged MHC class I expression following infection. In line with MHC class I expression, more NK cells produced a higher amount of IFN-γ against infected R2 cells compared with RmW cells. Together, L. monocytogenes infection may variously regulate cellular ligands for NK cells, depending on the cell type infected, affecting the outcome of NK cell responses.

  8. PIBF positive uterine NK cells in the mouse decidua.

    PubMed

    Bogdan, Agnes; Berta, Gergely; Szekeres-Bartho, Julia

    2017-02-01

    Though uterine NK cells (u NK cells) contain cytotoxic granules, and selectively over- express the genes of perforin and granzymes, during normal pregnancy, they are not cytotoxic. Progesterone is indispensable for the establishment and maintenance of pregnancy both in humans and in mice. Mouse uterine NK cells do not express the classical progesterone receptor, yet progesterone affects the recruitment and function of uterine NK cells, the latter partly via the Progesterone-Induced Blocking Factor (PIBF). We demonstrated PIBF positive granulated cells in the mouse decidua. The aim of this study was to characterize these cells by lectin immunohistochemistry and anti-perforin reactivity. PIBF+ granulated cells were absent from the deciduae of alymphoid mice, but appeared in the decidua of those that had been reconstituted with bone marrow from male BALB/c mice. PIBF+ granulated cells bound the DBA lectin, suggesting their NK cell nature, and also contained perforin, which co-localized with PIBF in the cytoplasmic granules. In anti-progesterone treated mice all of the PIBF+ cells were perforin positive at g. d. 12.5, in contrast to the 54% perforin positivity of PIBF+ cells in untreated mice.

  9. Acute GVHD in patients receiving IL-15/4-1BBL activated NK cells following T-cell-depleted stem cell transplantation.

    PubMed

    Shah, Nirali N; Baird, Kristin; Delbrook, Cynthia P; Fleisher, Thomas A; Kohler, Mark E; Rampertaap, Shakuntala; Lemberg, Kimberly; Hurley, Carolyn K; Kleiner, David E; Merchant, Melinda S; Pittaluga, Stefania; Sabatino, Marianna; Stroncek, David F; Wayne, Alan S; Zhang, Hua; Fry, Terry J; Mackall, Crystal L

    2015-01-29

    Natural killer (NK) cells can enhance engraftment and mediate graft-versus-leukemia following allogeneic hematopoietic stem cell transplantation (HSCT), but the potency of graft-versus-leukemia mediated by naturally reconstituting NK cells following HSCT is limited. Preclinical studies demonstrate that activation of NK cells using interleukin-15 (IL-15) plus 4-1BBL upregulates activating receptor expression and augments killing capacity. In an effort to amplify the beneficial effects of NK cells post-HSCT, we conducted a first-in-human trial of adoptive transfer of donor-derived IL-15/4-1BBL-activated NK cells (aNK-DLI) following HLA-matched, T-cell-depleted (1-2 × 10(4) T cells/kg) nonmyeloablative peripheral blood stem cell transplantation in children and young adults with ultra-high-risk solid tumors. aNK-DLI were CD3(+)-depleted, CD56(+)-selected lymphocytes, cultured for 9 to 11 days with recombinant human IL-15 plus 4-1BBL(+)IL-15Rα(+) artificial antigen-presenting cells. aNK-DLI demonstrated potent killing capacity and displayed high levels of activating receptor expression. Five of 9 transplant recipients experienced acute graft-versus-host disease (GVHD) following aNK-DLI, with grade 4 GVHD observed in 3 subjects. GVHD was more common in matched unrelated donor vs matched sibling donor recipients and was associated with higher donor CD3 chimerism. Given that the T-cell dose was below the threshold required for GVHD in this setting, we conclude that aNK-DLI contributed to the acute GVHD observed, likely by augmenting underlying T-cell alloreactivity. This trial was registered at www.clinicaltrials.gov as #NCT01287104.

  10. Low-dose bortezomib increases the expression of NKG2D and DNAM-1 ligands and enhances induced NK and γδ T cell-mediated lysis in multiple myeloma

    PubMed Central

    Zhu, Shan; Zhou, Lei; Jin, Feng; Zhou, Yulai; Xu, Dongsheng; Xu, Jianting; Zhao, Lianjing; Hao, Shanshan; Li, Wei; Cui, Jiuwei

    2017-01-01

    Multiple myeloma (MM) is an incurable hematological malignancy, although bortezomib has markedly improved its outcomes. Growing clinical evidence indicates that enhancing induced natural killer (NK) or γδ T cells for infusion is useful in the treatment of MM. However, whether combination treatment with bortezomib and induced NK and γδ T cells further improves outcomes in MM, and how the treatments should be combined, remain unclear. Herein, we found that low-dose bortezomib did not suppress the viability of induced NK and γδ T cells, but did induce MM cell apoptosis. Importantly, low-dose bortezomib increased the expression of NKG2D and DNAM-1 ligands on MM cells, which sensitized the multiple myeloma cells to lysis by induced NK and γδ T cells. Our results suggested that combination treatment with low-dose bortezomib and induced NK or γδ T cells had a synergistic cytotoxic effect on MM cells. This study provided a proof of principle for the design of future trials and investigation of this combination therapeutic strategy for MM treatment. PMID:27992381

  11. Using NK Cell Lipid Raft Fractionation to Understand the Role of Lipid Rafts in NK Cell Receptor Signaling.

    PubMed

    Serrano-Pertierra, Esther; López-Larrea, Carlos

    2016-01-01

    Lipid rafts were first defined as detergent-resistant membranes (DRMs) due to their relative insolubility in non-ionic detergents. Although they should not be confused with lipid rafts, DRMs are a valuable starting point for the study of these membrane domains and the interactions of proteins with rafts.Here we describe the isolation of DRMs by ultracentrifugation on a sucrose gradient, a method we have used to study the role of lipid rafts in NKG2D-mediated signaling. We also describe raft fractionation of NK cells involving the selective solubility of β-octylglucoside (β-OG). OG is a non-ionic detergent that efficiently dissolves DRMs but does not disrupt protein associations with the cytoskeleton. Using these two techniques may yield useful information about the proteins involved in receptor recruitment into lipid rafts and the interactions of the actin cytoskeleton with lipid rafts.

  12. Kinetics of Cytotoxic Lymphocytes Reconstitution after Induction Chemotherapy in Elderly AML Patients Reveals Progressive Recovery of Normal Phenotypic and Functional Features in NK Cells.

    PubMed

    Rey, Jérôme; Fauriat, Cyril; Kochbati, Eloïse; Orlanducci, Florence; Charbonnier, Aude; D'Incan, Evelyne; Andre, Pascale; Romagne, François; Barbarat, Bernadette; Vey, Norbert; Olive, Daniel

    2017-01-01

    NK cells are defective in acute myeloid leukemia (AML) at diagnosis. Here, we studied the kinetic of expression of the major activating and inhibitory receptors of NK, CD8 T, and γδ T cells in patients undergoing chemotherapy (CT) for the treatment of AML (n = 29). We showed that NK cells are the main affected population at diagnosis and that expression of activating receptors is partially restored within a few weeks after CT. CD8 T cells and γδ T cells are only weakly affected at diagnosis. Killer cell immunoglobulin-like receptor expression by NK cells, but not NKG2A and CD85j, was downregulated. Interestingly, the development of NK cells appeared altered as the most immature CD56(bright) NK cells were seriously underrepresented. Finally, we showed that NK cell functions were only partially restored 6 weeks after CT as degranulation capabilities of NK cells recovered, whereas cytokine production remained low. Our data point out NK cells as antitumor effectors peculiarly hampered by leukemic cells. This study may indicate a timeline when NK-mediated therapies or other immunotherapies could be performed, particularly for patients excluded of hematopoietic stem cell transplantation.

  13. Kinetics of Cytotoxic Lymphocytes Reconstitution after Induction Chemotherapy in Elderly AML Patients Reveals Progressive Recovery of Normal Phenotypic and Functional Features in NK Cells

    PubMed Central

    Rey, Jérôme; Fauriat, Cyril; Kochbati, Eloïse; Orlanducci, Florence; Charbonnier, Aude; D’Incan, Evelyne; Andre, Pascale; Romagne, François; Barbarat, Bernadette; Vey, Norbert; Olive, Daniel

    2017-01-01

    NK cells are defective in acute myeloid leukemia (AML) at diagnosis. Here, we studied the kinetic of expression of the major activating and inhibitory receptors of NK, CD8 T, and γδ T cells in patients undergoing chemotherapy (CT) for the treatment of AML (n = 29). We showed that NK cells are the main affected population at diagnosis and that expression of activating receptors is partially restored within a few weeks after CT. CD8 T cells and γδ T cells are only weakly affected at diagnosis. Killer cell immunoglobulin-like receptor expression by NK cells, but not NKG2A and CD85j, was downregulated. Interestingly, the development of NK cells appeared altered as the most immature CD56bright NK cells were seriously underrepresented. Finally, we showed that NK cell functions were only partially restored 6 weeks after CT as degranulation capabilities of NK cells recovered, whereas cytokine production remained low. Our data point out NK cells as antitumor effectors peculiarly hampered by leukemic cells. This study may indicate a timeline when NK-mediated therapies or other immunotherapies could be performed, particularly for patients excluded of hematopoietic stem cell transplantation. PMID:28210257

  14. Inflammasome-Dependent Induction of Adaptive NK Cell Memory.

    PubMed

    van den Boorn, Jasper G; Jakobs, Christopher; Hagen, Christian; Renn, Marcel; Luiten, Rosalie M; Melief, Cornelis J M; Tüting, Thomas; Garbi, Natalio; Hartmann, Gunther; Hornung, Veit

    2016-06-21

    Monobenzone is a pro-hapten that is exclusively metabolized by melanocytes, thereby haptenizing melanocyte-specific antigens, which results in cytotoxic autoimmunity specifically against pigmented cells. Studying monobenzone in a setting of contact hypersensitivity (CHS), we observed that monobenzone induced a long-lasting, melanocyte-specific immune response that was dependent on NK cells, yet fully intact in the absence of T- and B cells. Consistent with the concept of "memory NK cells," monobenzone-induced NK cells resided in the liver and transfer of these cells conferred melanocyte-specific immunity to naive animals. Monobenzone-exposed skin displayed macrophage infiltration and cutaneous lymph nodes showed an inflammasome-dependent influx of macrophages with a tissue-resident phenotype, coinciding with local NK cell activation. Indeed, macrophage depletion or the absence of the NLRP3 inflammasome, the adaptor protein ASC or interleukin-18 (IL-18) abolished monobenzone CHS, thereby establishing a non-redundant role for the NLRP3 inflammasome as a critical proinflammatory checkpoint in the induction of hapten-dependent memory NK cells.

  15. Regulation of NK-cell function by mucins via antigen-presenting cells.

    PubMed

    Laskarin, G; Redzovic, A; Medancic, S Srsen; Rukavina, D

    2010-12-01

    Decidual antigen-presenting cells including dendritic cells (DCs) and CD14(+) macrophages, as mediators of the first encounter with fetal antigens, appear to be critically involved in the initiation of primary immune response by regulating innate- and adaptive immunity. Interleukin-15, produced by them, permits the proliferation and differentiation of CD3(-)CD16(-)CD94(+)NKG2A(+)CD56(+bright) decidual NK cells that identify trophoblast cells. These cells are able to kill them after Th1 cytokine overstimulation and by increasing the release of preformed cytotoxic mediators. Thus, the local microenvironment is a potent modulator of antigen-presenting cell functions. Tumor associated glycoprotein-72 (TAG-72) and mucine 1 (MUC-1) are glycoproteins secreted by uterine epithelial cells. Our hypothesis is that TAG-72 and MUC-1 are the natural ligands for carbohydrate recognition domains (CRDs) of endocytic mannose receptor (MR or CD206) and DC-specific ICAM non-integrin (DC-SIGN or CD209) expressed on decidual CD14(+) macrophages and CD1a(+) DCs. They might be able to condition antigen-presenting cells to produce distinct profiles of cyto/chemokines with consequential reduction in NK-cell numbers and cytotoxic potential leading to insufficient control over trophoblast growth. This hypothesis could explain the disappearance of MUC-1 beneath the attached embryo during the process of successful implantation when tight regulation of trophoblast invasion is needed. As IL-15 is the earliest and the most important factor in NK-cell proliferation, differentiation, and maturation, we expected primarily an increase of IL-15 expression in antigen-presenting cells concomitant with the disappearance of mucins and the enhancement in NK cells numbers and of cytotoxic potential after their close contact with early pregnancy decidual antigen-presenting cells. If our hypothesis is correct, it would contribute to the understanding of the role of mucins in the redirection of immune response

  16. Differentiation by NK cells is a prerequisite for effective targeting of cancer stem cells/poorly differentiated tumors by chemopreventive and chemotherapeutic drugs

    PubMed Central

    Kozlowska, Anna Karolina; Topchyan, Paytsar; Kaur, Kawaljit; Tseng, Han-Ching; Teruel, Antonia; Hiraga, Toru; Jewett, Anahid

    2017-01-01

    Natural Killer (NK) cells target oral, pancreatic, lung, breast, glioblastoma and melanoma stem-like/poorly differentiated tumors. Differentiation of the abovementioned tumors with supernatants from split-anergized NK cells decreases their susceptibility to NK cells, but increases their sensitivity to cisplatin (CDDP)-mediated cell death. Breast and melanoma tumor cells with CD44 knockdown display enhanced susceptibility to NK cell-mediated lysis, potentially due to decreased differentiation. We also demonstrate that sulindac, a non-steroidal anti-inflammatory drug and a chemopreventive agent, not only limits the growth of oral tumor cells, but also aids in cancer cell elimination by NK cells. Treatment of oral tumors with sulindac, but not adriamycin inversely modulates the expression and function of NFκB and JNK, resulting in a significant down-regulation of IL-6, and VEGF secretion by oral tumor cells. In addition, increased secretion of IL-6 and VEGF is blocked by sulindac during interaction of oral tumors with NK cells. Sulindac treatment prevents synergistic induction of VEGF secretion by the tumor cells after their co-culture with untreated NK cells since non-activated NK cells lack the ability to efficiently kill tumor cells. Moreover, sulindac is able to profoundly reduce VEGF secretion by tumor cells cultured with IL-2 activated NK cells, which are able to significantly lyse the tumor cells. Based on the data presented in this study, we propose the following combinatorial approach for the treatment of stem-like/ poorly differentiated tumors in cancer patients with metastatic disease. Stem-like/ poorly differentiated tumor cells may in part undergo lysis or differentiation after NK cell immunotherapy, followed by treatment of differentiated tumors with chemotherapy and chemopreventive agents to eliminate the bulk of the tumor. This dual approach should limit tumor growth and prevent metastasis. PMID:28367234

  17. T and NK cells: two sides of tumor immunoevasion.

    PubMed

    Fruci, Doriana; Lo Monaco, Elisa; Cifaldi, Loredana; Locatelli, Franco; Tremante, Elisa; Benevolo, Maria; Giacomini, Patrizio

    2013-02-04

    Natural Killer (NK) cells are known to reject several experimental murine tumors, but their antineoplastic activity in humans is not generally agreed upon, as exemplified by an interesting correspondence recently appeared in Cancer Research. In the present commentary, we join the discussion and bring to the attention of the readers of the Journal of Translational Medicine a set of recent, related reports. These studies demonstrate that effectors of the adaptive and innate immunity need to actively cooperate in order to reject tumors and, conversely, tumors protect themselves by dampening both T and NK cell responses. The recently reported ability of indoleamine 2,3-dioxygenase (IDO) and prostaglandin E2 (PGE2) expressed by melanoma cells to down-regulate activating NK receptors is yet another piece of evidence supporting combined and highly effective T/NK cell disabling. Major Histocompatibility Complex class I (MHC-I) molecules, including Human Leukocyte Antigen E (HLA-E), represent another class of shared activating/inhibitory ligands. Ongoing clinical trials with small molecules interfering with IDO and PGE2 may be exploiting an immune bonus to control cancer. Conversely, failure to simultaneously engage effectors of both the innate and the adaptive immunity may contribute to explain the limited clinical efficacy of T cell-only vaccination trials. Shared (T/NK cells) natural immunosuppressants and activating/inhibitory ligands expressed by tumor cells may provide mechanistic insight into impaired gathering and function of immune effectors at the tumor site.

  18. T and NK cells: two sides of tumor immunoevasion

    PubMed Central

    2013-01-01

    Natural Killer (NK) cells are known to reject several experimental murine tumors, but their antineoplastic activity in humans is not generally agreed upon, as exemplified by an interesting correspondence recently appeared in Cancer Research. In the present commentary, we join the discussion and bring to the attention of the readers of the Journal of Translational Medicine a set of recent, related reports. These studies demonstrate that effectors of the adaptive and innate immunity need to actively cooperate in order to reject tumors and, conversely, tumors protect themselves by dampening both T and NK cell responses. The recently reported ability of indoleamine 2,3-dioxygenase (IDO) and prostaglandin E2 (PGE2) expressed by melanoma cells to down-regulate activating NK receptors is yet another piece of evidence supporting combined and highly effective T/NK cell disabling. Major Histocompatibility Complex class I (MHC-I) molecules, including Human Leukocyte Antigen E (HLA-E), represent another class of shared activating/inhibitory ligands. Ongoing clinical trials with small molecules interfering with IDO and PGE2 may be exploiting an immune bonus to control cancer. Conversely, failure to simultaneously engage effectors of both the innate and the adaptive immunity may contribute to explain the limited clinical efficacy of T cell-only vaccination trials. Shared (T/NK cells) natural immunosuppressants and activating/inhibitory ligands expressed by tumor cells may provide mechanistic insight into impaired gathering and function of immune effectors at the tumor site. PMID:23379575

  19. Tumour-experienced T cells promote NK cell activity through trogocytosis of NKG2D and NKp46 ligands

    PubMed Central

    Domaica, Carolina I; Fuertes, Mercedes B; Rossi, Lucas E; Girart, María V; Ávila, Damián E; Rabinovich, Gabriel A; Zwirner, Norberto W

    2009-01-01

    Natural killer (NK) cells trigger cytotoxicity and interferon (IFN)-γ secretion on engagement of the natural-killer group (NKG)2D receptor or members of the natural cytotoxicity receptor (NCR) family, such as NKp46, by ligands expressed on tumour cells. However, it remains unknown whether T cells can regulate NK cell-mediated anti-tumour responses. Here, we investigated the early events occurring during T cell–tumour cell interactions, and their impact on NK cell functions. We observed that on co-culture with some melanomas, activated CD4+ T cells promoted degranulation, and NKG2D- and NKp46-dependent IFN-γ secretion by NK cells, probably owing to the capture of NKG2D and NKp46 ligands from the tumour-cell surface (trogocytosis). This effect was observed in CD4+, CD8+ and resting T cells, which showed substantial amounts of cell surface major histocompatibility complex class I chain-related protein A on co-culture with tumour cells. Our findings identify a new, so far, unrecognized mechanism by which effector T cells support NK cell function through the capture of specific tumour ligands with profound implications at the crossroad of innate and adaptive immunity. PMID:19498463

  20. Application of tissue-specific NK and NKT cell activity for tumor immunotherapy

    PubMed Central

    Subleski, Jeff J.; Wiltrout, Robert H.; Weiss, Jonathan M.

    2009-01-01

    Natural killer (NK) and NKT cells are a first line of defense against pathogens and transformed cells. However, dysregulation of their function can lead to autoimmune disease. A better understanding of the mechanisms controlling NK and NKT effector function should lead to the development of improved strategies for the treatment of many diseases. The site in which NK and NKT cells reside should be taken into account, because accumulating evidence suggests that the tissue microenvironment strongly influences their function. In this regard, the liver represents a unique immunologic organ in which the balance between the need for tolerance and the ability to respond rapidly to pathogens and tissue injury is tightly regulated. NK cells in the liver have augmented cytolytic activity as compared to other organs, which is consistent with a role for liver-associated NK cells in being critical effector cells for inhibiting tumor metastasis in the liver. Several studies also suggest that hepatic NKT cells have different functions than those in other organs. Whereas splenic and thymic NKT cells have been shown to suppress diabetes development, facilitate the induction of systemic tolerance and are regulated by IL-4 and other Th2 cytokines, certain subsets of NKT cells in the liver are important sources of Th1 cytokines such as Interferon gamma, and are the primary mediators of anti-tumor responses. The unique properties and roles as critical effector cells make NK and NKT cells within the liver microenvironment attractive targets of immunotherapeutic approaches that have the goal of controlling tumor metastasis in the liver. PMID:19682859

  1. Natural killer (NK) cell deficit in coronary artery disease: no aberrations in phenotype but sustained reduction of NK cells is associated with low-grade inflammation.

    PubMed

    Backteman, K; Ernerudh, J; Jonasson, L

    2014-01-01

    Although reduced natural killer (NK) cell levels have been reported consistently in patients with coronary artery disease (CAD), the clinical significance and persistence of this immune perturbation is not clarified. In this study we characterized the NK cell deficit further by determining (i) differentiation surface markers and cytokine profile of NK cell subsets and (ii) ability to reconstitute NK cell levels over time. Flow cytometry was used to analyse NK cell subsets and the intracellular cytokine profile in 31 patients with non-ST elevation myocardial infarction (non-STEMI), 34 patients with stable angina (SA) and 37 healthy controls. In blood collected prior to coronary angiography, the proportions of NK cells were reduced significantly in non-STEMI and SA patients compared with controls, whereas NK cell subset analyses or cytokine profile measurements did not reveal any differences across groups. During a 12-month follow-up, the proportions of NK cells increased, although not in all patients. Failure to reconstitute NK cell levels was associated with several components of metabolic syndrome. Moreover, interleukin (IL)-6 levels remained high in patients with sustained NK cell deficit, whereas a decline in IL-6 (P < 0·001) was seen in patients with a pronounced increase in NK cells. In conclusion, we found no evidence that reduction of NK cells in CAD patients was associated with aberrations in NK cell phenotype at any clinical stage of the disease. Conversely, failure to reconstitute NK cell levels was associated with a persistent low-grade inflammation, suggesting a protective role of NK cells in CAD.

  2. Immunomodulation of endothelial differentiated mesenchymal stromal cells: impact on T and NK cells.

    PubMed

    El Omar, Reine; Xiong, Yu; Dostert, Gabriel; Louis, Huguette; Gentils, Monique; Menu, Patrick; Stoltz, Jean-François; Velot, Émilie; Decot, Véronique

    2016-04-01

    Wharton's jelly mesenchymal stromal cells (WJ-MSCs) are promising candidates for tissue engineering, as their immunomodulatory activity allows them to escape immune recognition and to suppress several immune cell functions. To date, however, few studies have investigated the effect of differentiation of the MSCs on this immunomodulation. To address this question, we sought to determine the impact of differentiation toward endothelial cells on immunoregulation by WJ-MSCs. Following differentiation, the endothelial-like cells (ELCs) were positive for CD31, vascular endothelial cadherin and vascular endothelial growth factor receptor 2, and able to take up acetylated low-density lipoproteins. The expression of HLA-DR and CD86, which contribute to MSCs immunoprivilege, was still weak after differentiation. We then co-cultured un- and differentiated MSCs with immune cells, under conditions of both direct and indirect contact. The proliferation and phenotype of the immune cells were analyzed and the mediators secreted by both ELCs and WJ-MSCs quantified. Interleukin (IL)-6, IL-1β, prostaglandin E2 and in particular indoleamine-2,3-dioxygenase expression were upregulated in ELCs on stimulation by T and NK cells, suggesting the possible involvement of these factors in allosuppression. ELCs co-cultured with T cells were able to generate CD25(+) T cells, which were shown to be of the CD4(+)CD25(+)FoxP3(+) regulatory subset. Direct contact between NK cells and ELCs or WJ-MSCs decreased the level of NK-activating receptor natural-killer group 2, member D. Moreover, direct co-culturing with ELCs stimulates CD73 acquisition on NK cells, a mechanism which may induce adenosine secretion by the cells and lead to an immunosuppressive function. Taken together, our results show that ELCs obtained following differentiation of WJ-MSCs remain largely immunosuppressive.

  3. Enteropathy-type T-cell lymphoma expressing NK-cell intraepithelial lymphocyte (NK-IEL) phenotype.

    PubMed

    Inagaki, Naoko; Asaoka, Daisuke; Mori, Kiyoshi L; Sohda, Naomi; Miura, Ichiro; Miwa, Hiroto; Sato, Nobuhiro; Oshimi, Kazuo

    2004-07-01

    Enteropathy-type T-cell lymphoma (ETL) is an intraepithelial T-lymphocyte (T-IEL) tumor. The tumor cells are usually CD3+, CD4-, CD8+, and contain cytotoxic granule associated proteins. We report on a CD3-negative CD56-positive enteropathy-associated lymphoma (ETL). This is the first case report of CD3-negative, CD56-positive, CD94-negative, and CD161-positive ETL. ETL cells originate from intraepithelial T-lymphocytes of the intestine. CD3-negative intraepithelial lymphocytes are known as natural killer (NK)-IELs. The phenotype of NK-IELs is also CD3-negative, CD56-positive, CD94-negative, and CD161-positive, while most normal NK cells express CD56 and CD94. CD3-negative lymphoma cells in this report also expressed CD56 and CD161, but not CD94. Because Southern blotting analysis showed a rearrangement of T-cell receptor (TCR) Cbeta in this case, the tumor is classified as an ETL. Based on the findings, NK-IELs may originate from T-cells, not NK-cells.

  4. In Vivo Efficacy of Umbilical Cord Blood Stem Cell-Derived NK Cells in the Treatment of Metastatic Colorectal Cancer.

    PubMed

    Veluchamy, John P; Lopez-Lastra, Silvia; Spanholtz, Jan; Bohme, Fenna; Kok, Nina; Heideman, Daniëlle A M; Verheul, Henk M W; Di Santo, James P; de Gruijl, Tanja D; van der Vliet, Hans J

    2017-01-01

    Therapeutic monoclonal antibodies against the epidermal growth factor receptor (EGFR) act by inhibiting EGFR downstream signaling and by eliciting a natural killer (NK) cell-mediated antitumor response. The IgG1 mAb cetuximab has been used for treatment of RAS(wt) metastatic colorectal cancer (mCRC) patients, showing limited efficacy. In the present study, we address the potential of adoptive NK cell therapy to overcome these limitations investigating two allogeneic NK cell products, i.e., allogeneic activated peripheral blood NK cells (A-PBNK) and umbilical cord blood stem cell-derived NK cells (UCB-NK). While cetuximab monotherapy was not effective against EGFR(-) RAS(wt), EGFR(+) RAS(mut), and EGFR(+) BRAF(mut) cells, A-PBNK were able to initiate lysis of EGFR(+) colon cancer cells irrespective of RAS or BRAF status. Cytotoxic effects of A-PBNK (but not UCB-NK) were further potentiated significantly by coating EGFR(+) colon cancer cells with cetuximab. Of note, a significantly higher cytotoxicity was induced by UCB-NK in EGFR(-)RAS(wt) (42 ± 8 versus 67 ± 7%), EGFR(+) RAS(mut) (20 ± 2 versus 37 ± 6%), and EGFR(+) BRAF(mut) (23 ± 3 versus 43 ± 7%) colon cancer cells compared to A-PBNK and equaled the cytotoxic efficacy of the combination of A-PBNK and cetuximab. The antitumor efficacy of UCB-NK cells against cetuximab-resistant human EGFR(+) RAS(mut) colon cancer cells was further confirmed in an in vivo preclinical mouse model where UCB-NK showed enhanced antitumor cytotoxicity against colon cancer independent of EGFR and RAS status. As UCB-NK have been proven safe in a recently conducted phase I clinical trial in acute myeloid leukemia, a fast translation into clinical proof of concept for mCRC could be considered.

  5. IL-18-induced expression of high-affinity IL-2R on murine NK cells is essential for NK-cell IFN-γ production during murine Plasmodium yoelii infection.

    PubMed

    Stegmann, Kerstin A; De Souza, J Brian; Riley, Eleanor M

    2015-12-01

    Early production of pro-inflammatory cytokines, including IFN-γ, is essential for control of blood-stage malaria infections. We have shown that IFN-γ production can be induced among human natural killer (NK) cells by coculture with Plasmodium falciparum infected erythrocytes, but the importance of this response is unclear. To further explore the role of NK cells during malaria infection, we have characterized the NK-cell response of C57BL/6 mice during lethal (PyYM) or nonlethal (Py17XNL) P. yoelii infection. Ex vivo flow cytometry revealed that NK cells are activated within 24 h of Py17XNL blood-stage infection, expressing CD25 and producing IFN-γ; this response was blunted and delayed during PyYM infection. CD25 expression and IFN-γ production were highly correlated, suggesting a causal relationship between the two responses. Subsequent in vitro experiments revealed that IL-18 signaling is essential for induction of CD25 and synergizes with IL-12 to enhance CD25 expression on splenic NK cells. In accordance with this, Py17XNL-infected erythrocytes induced NK-cell CD25 expression and IFN-γ production in a manner that is completely IL-18- and partially IL-12-dependent, and IFN-γ production is enhanced by IL-2. These data suggest that IL-2 signaling via CD25 amplifies IL-18- and IL-12-mediated NK-cell activation during malaria infection.

  6. Regulatory T cells inhibit CD34+ cell differentiation into NK cells by blocking their proliferation

    PubMed Central

    Pedroza-Pacheco, Isabela; Shah, Divya; Domogala, Anna; Luevano, Martha; Blundell, Michael; Jackson, Nicola; Thrasher, Adrian; Madrigal, Alejandro; Saudemont, Aurore

    2016-01-01

    Graft versus Host Disease (GvHD) remains one of the main complications after hematopoietic stem cell transplantation (HSCT). Due to their ability to suppress effector cells, regulatory T cells (Tregs) have been proposed as a cellular therapy to prevent GvHD, however they also inhibit the functions of natural killer (NK) cells, key effectors of the Graft versus Leukemia effect. In this study, we have explored whether a Tregs therapy will also impact on NK cell differentiation. Using an in vitro model of hematopoietic stem cell (HSC) differentiation into NK cells, we found that activated Tregs led to a 90% reduction in NK cell numbers when added at the time of commitment to the NK cell lineage. This effect was contact dependent and was reversible upon Tregs depletion. The few NK cells that developed in these cultures were mature and exhibited normal functions. Furthermore, adoptive transfer of activated Tregs in rag-/- γc-/- mice abrogated HSC differentiation into NK cells thus confirming our in vitro findings. Collectively, these results demonstrate for the first time that activated Tregs can inhibit NK cell differentiation from HSC under specific conditions. PMID:26915707

  7. Regulatory T cells inhibit CD34+ cell differentiation into NK cells by blocking their proliferation.

    PubMed

    Pedroza-Pacheco, Isabela; Shah, Divya; Domogala, Anna; Luevano, Martha; Blundell, Michael; Jackson, Nicola; Thrasher, Adrian; Madrigal, Alejandro; Saudemont, Aurore

    2016-02-26

    Graft versus Host Disease (GvHD) remains one of the main complications after hematopoietic stem cell transplantation (HSCT). Due to their ability to suppress effector cells, regulatory T cells (Tregs) have been proposed as a cellular therapy to prevent GvHD, however they also inhibit the functions of natural killer (NK) cells, key effectors of the Graft versus Leukemia effect. In this study, we have explored whether a Tregs therapy will also impact on NK cell differentiation. Using an in vitro model of hematopoietic stem cell (HSC) differentiation into NK cells, we found that activated Tregs led to a 90% reduction in NK cell numbers when added at the time of commitment to the NK cell lineage. This effect was contact dependent and was reversible upon Tregs depletion. The few NK cells that developed in these cultures were mature and exhibited normal functions. Furthermore, adoptive transfer of activated Tregs in rag(-/-) γc(-/-) mice abrogated HSC differentiation into NK cells thus confirming our in vitro findings. Collectively, these results demonstrate for the first time that activated Tregs can inhibit NK cell differentiation from HSC under specific conditions.

  8. TLR9-dependent recognition of MCMV by IPC and DC generates coordinated cytokine responses that activate antiviral NK cell function.

    PubMed

    Krug, Anne; French, Anthony R; Barchet, Winfried; Fischer, Jens A A; Dzionek, Andrzej; Pingel, Jeanette T; Orihuela, Michael M; Akira, Shizuo; Yokoyama, Wayne M; Colonna, Marco

    2004-07-01

    Natural interferon-producing cells (IPC) respond to viruses by secreting type I interferon (IFN) and interleukin-12 (IL-12). Toll-like receptor (TLR) 9 mediates IPC recognition of some of these viruses in vitro. However, whether TLR9-induced activation of IPC is necessary for an effective antiviral response in vivo is not clear. Here, we demonstrate that IPC and dendritic cells (DC) recognize murine cytomegalovirus (MCMV) through TLR9. TLR9-mediated cytokine secretion promotes viral clearance by NK cells that express the MCMV-specific receptor Ly49H. Although depletion of IPC leads to a drastic reduction of the IFN-alpha response, this allows other cell types to secrete IL-12, ensuring normal IFN-gamma and NK cell responses to MCMV. We conclude that the TLR9/MyD88 pathway mediates antiviral cytokine responses by IPC, DC, and possibly other cell types, which are coordinated to promote effective NK cell function and MCMV clearance.

  9. Candida albicans Induces Metabolic Reprogramming in Human NK Cells and Responds to Perforin with a Zinc Depletion Response.

    PubMed

    Hellwig, Daniela; Voigt, Jessica; Bouzani, Maria; Löffler, Jürgen; Albrecht-Eckardt, Daniela; Weber, Michael; Brunke, Sascha; Martin, Ronny; Kurzai, Oliver; Hünniger, Kerstin

    2016-01-01

    As part of the innate immune system, natural killer (NK) cells are directly involved in the response to fungal infections. Perforin has been identified as the major effector molecule acting against many fungal pathogens. While several studies have shown that perforin mediated fungicidal effects can contribute to fungal clearance, neither the activation of NK cells by fungal pathogens nor the effects of perforin on fungal cells are well-understood. In a dual approach, we have studied the global gene expression pattern of primary and cytokine activated NK cells after co-incubation with Candida albicans and the transcriptomic adaptation of C. albicans to perforin exposure. NK cells responded to the fungal pathogen with an up-regulation of genes involved in immune signaling and release of cytokines. Furthermore, we observed a pronounced increase of genes involved in glycolysis and glycolysis inhibitor 2-deoxy-D-glucose impaired C. albicans induced NK cell activation. This strongly indicates that metabolic adaptation is a major part of the NK cell response to C. albicans infections. In the fungal pathogen, perforin induced a strong up-regulation of several fungal genes involved in the zinc depletion response, such as PRA1 and ZRT1. These data suggest that fungal zinc homeostasis is linked to the reaction to perforin secreted by NK cells. However, deletion mutants in PRA1 and ZRT1 did not show altered susceptibility to perforin.

  10. Candida albicans Induces Metabolic Reprogramming in Human NK Cells and Responds to Perforin with a Zinc Depletion Response

    PubMed Central

    Hellwig, Daniela; Voigt, Jessica; Bouzani, Maria; Löffler, Jürgen; Albrecht-Eckardt, Daniela; Weber, Michael; Brunke, Sascha; Martin, Ronny; Kurzai, Oliver; Hünniger, Kerstin

    2016-01-01

    As part of the innate immune system, natural killer (NK) cells are directly involved in the response to fungal infections. Perforin has been identified as the major effector molecule acting against many fungal pathogens. While several studies have shown that perforin mediated fungicidal effects can contribute to fungal clearance, neither the activation of NK cells by fungal pathogens nor the effects of perforin on fungal cells are well-understood. In a dual approach, we have studied the global gene expression pattern of primary and cytokine activated NK cells after co-incubation with Candida albicans and the transcriptomic adaptation of C. albicans to perforin exposure. NK cells responded to the fungal pathogen with an up-regulation of genes involved in immune signaling and release of cytokines. Furthermore, we observed a pronounced increase of genes involved in glycolysis and glycolysis inhibitor 2-deoxy-D-glucose impaired C. albicans induced NK cell activation. This strongly indicates that metabolic adaptation is a major part of the NK cell response to C. albicans infections. In the fungal pathogen, perforin induced a strong up-regulation of several fungal genes involved in the zinc depletion response, such as PRA1 and ZRT1. These data suggest that fungal zinc homeostasis is linked to the reaction to perforin secreted by NK cells. However, deletion mutants in PRA1 and ZRT1 did not show altered susceptibility to perforin. PMID:27242763

  11. Suppression of NK cells and regulatory T lymphocytes in cats naturally infected with feline infectious peritonitis virus.

    PubMed

    Vermeulen, Ben L; Devriendt, Bert; Olyslaegers, Dominique A; Dedeurwaerder, Annelike; Desmarets, Lowiese M; Favoreel, Herman W; Dewerchin, Hannah L; Nauwynck, Hans J

    2013-05-31

    A strong cell-mediated immunity (CMI) is thought to be indispensable for protection against infection with feline infectious peritonitis virus (FIPV) in cats. In this study, the role of natural killer (NK) cells and regulatory T cells (Tregs), central players in the innate and adaptive CMI respectively, was examined during natural FIPV infection. When quantified, both NK cells and Tregs were drastically depleted from the peripheral blood, mesenteric lymph node (LN) and spleen in FIP cats. In contrast, mesentery and kidney from FIP cats did not show any difference when compared to healthy non-infected control animals. In addition, other regulatory lymphocytes (CD4+CD25-Foxp3+ and CD3+CD8+Foxp3+) were found to be depleted from blood and LN as well. Phenotypic analysis of blood-derived NK cells in FIP cats revealed an upregulation of activation markers (CD16 and CD25) and migration markers (CD11b and CD62L) while LN-derived NK cells showed upregulation of only CD16 and CD62L. LN-derived NK cells from FIPV-infected cats were also significantly less cytotoxic when compared with healthy cats. This study reveals for the first time that FIPV infection is associated with severe suppression of NK cells and Tregs, which is reflected by cell depletion and lowered cell functionality (only NK cells). This will un-doubtfully lead to a reduced capacity of the innate immune system (NK cells) to battle FIPV infection and a decreased capacity (Tregs) to suppress the immunopathology typical for FIP. However, these results will also open possibilities for new therapies targeting specifically NK cells and Tregs to enhance their numbers and/or functionality during FIPV infection.

  12. NK Cell Subgroups, Phenotype, and Functions After Autologous Stem Cell Transplantation.

    PubMed

    Jacobs, Benedikt; Tognarelli, Sara; Poller, Kerstin; Bader, Peter; Mackensen, Andreas; Ullrich, Evelyn

    2015-01-01

    High-dose chemotherapy with consecutive autologous stem cell transplantation (autoSCT) is a well-established treatment option for patients suffering from malignant lymphoma or multiple myeloma. Natural killer (NK) cells are an important part of the immune surveillance, and their cell number after autoSCT is predictive for progression-free and overall survival. To improve knowledge about the role of NK cells after autoSCT, we investigated different NK cell subgroups, their phenotype, and their functions in patients treated with autoSCT. Directly after leukocyte regeneration (>1000 leukocytes/μl) following autoSCT, CD56(++) NK cells were the major NK cell subset. Surprisingly, these cells showed unusually high surface expression levels of CD57 and killer Ig-like receptors (KIRs) compared to expression levels before or at later time points after autoSCT. Moreover, these NK cells strongly upregulated KIR2DL2/3/S2 and KIR3DL1, whereas KIR2DL1/S1 remained constant, indicating that this cell population arose from more immature NK cells instead of from activated mature ones. Remarkably, NK cells were already able to degranulate and produce IFN-γ and MIP-1β upon tumor interaction early after leukocyte regeneration. In conclusion, we describe an unusual upregulation of CD57 and KIRs on CD56(++) NK cells shortly after autoSCT. Importantly, these NK cells were functionally competent upon tumor interaction at this early time point.

  13. Regulation of NK Cell Activation and Effector Functions by the IL-12 Family of Cytokines: The Case of IL-27.

    PubMed

    Zwirner, Norberto Walter; Ziblat, Andrea

    2017-01-01

    Natural killer (NK) cells are characterized by their ability to detect and induce apoptosis of susceptible target cells and by secretion of immunoregulatory cytokines such as IFN-γ. Activation of these effector functions is triggered upon recognition of tumor and pathogen (mostly virus)-infected cells and because of a bidirectional cross talk that NK cells establish with other cells of myeloid origin such as dendritic cells (DC) and macrophages. A common characteristic of these myeloid cells is their ability to secrete different members of the IL-12 family of cytokines such as IL-12, IL-23, and IL-27 and cytokines such as IL-15 and IL-18. Although the effect of IL-12, IL-15, and IL-18 has been characterized, the effect of IL-23 and IL-27 on NK cells (especially human) remains ill-defined. Particularly, IL-27 is a cytokine with dual functions as it has been described as pro- and as anti-inflammatory in different experimental settings. Recent evidence indicates that this cytokine indeed promotes human NK cell activation, IFN-γ secretion, NKp46-dependent NK cell-mediated cytotoxicity, and antibody (Ab)-dependent NK cell-mediated cytotoxicity (ADCC) against monoclonal Ab-coated tumor cells. Remarkably, IL-27 also primes NK cells for IL-18 responsiveness, enhancing these functional responses. Consequently, IL-27 acts as a pro-inflammatory cytokine that, in concert with other DC-derived cytokines, hierarchically contributes to NK cells activation and effector functions, which likely contributes to foster the adaptive immune response in different physiopathological conditions.

  14. Regulation of NK Cell Activation and Effector Functions by the IL-12 Family of Cytokines: The Case of IL-27

    PubMed Central

    Zwirner, Norberto Walter; Ziblat, Andrea

    2017-01-01

    Natural killer (NK) cells are characterized by their ability to detect and induce apoptosis of susceptible target cells and by secretion of immunoregulatory cytokines such as IFN-γ. Activation of these effector functions is triggered upon recognition of tumor and pathogen (mostly virus)-infected cells and because of a bidirectional cross talk that NK cells establish with other cells of myeloid origin such as dendritic cells (DC) and macrophages. A common characteristic of these myeloid cells is their ability to secrete different members of the IL-12 family of cytokines such as IL-12, IL-23, and IL-27 and cytokines such as IL-15 and IL-18. Although the effect of IL-12, IL-15, and IL-18 has been characterized, the effect of IL-23 and IL-27 on NK cells (especially human) remains ill-defined. Particularly, IL-27 is a cytokine with dual functions as it has been described as pro- and as anti-inflammatory in different experimental settings. Recent evidence indicates that this cytokine indeed promotes human NK cell activation, IFN-γ secretion, NKp46-dependent NK cell-mediated cytotoxicity, and antibody (Ab)-dependent NK cell-mediated cytotoxicity (ADCC) against monoclonal Ab-coated tumor cells. Remarkably, IL-27 also primes NK cells for IL-18 responsiveness, enhancing these functional responses. Consequently, IL-27 acts as a pro-inflammatory cytokine that, in concert with other DC-derived cytokines, hierarchically contributes to NK cells activation and effector functions, which likely contributes to foster the adaptive immune response in different physiopathological conditions. PMID:28154569

  15. The role of NK cells in antitumor activity of dietary fucoidan from Undaria pinnatifida sporophylls (Mekabu).

    PubMed

    Maruyama, Hiroko; Tamauchi, Hidekazu; Iizuka, Mariko; Nakano, Takahisa

    2006-12-01

    Fucoidan from Mekabu (sporophyll of Undaria pinnatifida), a dietary alga, exerts antitumor activity possibly through enhancing the immune response. The present report describes the effects of dietary Mekabu fucoidan on the tumor growth of mouse A20 leukemia cells and on T cell-mediated immune responses in T cell receptor transgenic (DO-11 - 10 - Tg) mice. The animals were fed with a diet containing 1% Mekabu fucoidan (0.034 +/- 0.003 g/mouse/day) for 10 days and subcutaneously (s. c.) inoculated with A20 leukemia cells. Thereafter, the mice were fed with the diet containing fucoidan for 40 days. Mekabu fucoidan inhibited tumors by 65.4 %. We studied how the killer activities of T cell-mediated and natural killer (NK) cells are augmented in DO-11 - 10 mice fed with Mekabu fucoidan. The cytolytic activities of ovalbumin (OVA), which is specific against OVA-transfected A20 (OVA-A20) B lymphoma cells, and NK cells against YAC-1 were significantly enhanced in the mice fed with fucoidan compared with a basic diet. Thus, these findings suggested that Mekabu fucoidan mediates tumor destruction through Th1 cell and NK cell responses.

  16. Activated Allogeneic NK Cells Preferentially Kill Poor Prognosis B-Cell Chronic Lymphocytic Leukemia Cells.

    PubMed

    Sánchez-Martínez, Diego; Lanuza, Pilar M; Gómez, Natalia; Muntasell, Aura; Cisneros, Elisa; Moraru, Manuela; Azaceta, Gemma; Anel, Alberto; Martínez-Lostao, Luis; Villalba, Martin; Palomera, Luis; Vilches, Carlos; García Marco, José A; Pardo, Julián

    2016-01-01

    Mutational status of TP53 together with expression of wild-type (wt) IGHV represents the most widely accepted biomarkers, establishing a very poor prognosis in B-cell chronic lymphocytic leukemia (B-CLL) patients. Adoptive cell therapy using allogeneic HLA-mismatched Natural killer (NK) cells has emerged as an effective and safe alternative in the treatment of acute myeloid and lymphoid leukemias that do not respond to traditional therapies. We have described that allogeneic activated NK cells eliminate hematological cancer cell lines with multidrug resistance acquired by mutations in the apoptotic machinery. This effect depends on the activation protocol, being B-lymphoblastoid cell lines (LCLs) the most effective stimulus to activate NK cells. Here, we have further analyzed the molecular determinants involved in allogeneic NK cell recognition and elimination of B-CLL cells, including the expression of ligands of the main NK cell-activating receptors (NKG2D and NCRs) and HLA mismatch. We present preliminary data suggesting that B-CLL susceptibility significantly correlates with HLA mismatch between NK cell donor and B-CLL patient. Moreover, we show that the sensitivity of B-CLL cells to NK cells depends on the prognosis based on TP53 and IGHV mutational status. Cells from patients with worse prognosis (mutated TP53 and wt IGHV) are the most susceptible to activated NK cells. Hence, B-CLL prognosis may predict the efficacy of allogenic activated NK cells, and, thus, NK cell transfer represents a good alternative to treat poor prognosis B-CLL patients who present a very short life expectancy due to lack of effective treatments.

  17. Activated Allogeneic NK Cells Preferentially Kill Poor Prognosis B-Cell Chronic Lymphocytic Leukemia Cells

    PubMed Central

    Sánchez-Martínez, Diego; Lanuza, Pilar M.; Gómez, Natalia; Muntasell, Aura; Cisneros, Elisa; Moraru, Manuela; Azaceta, Gemma; Anel, Alberto; Martínez-Lostao, Luis; Villalba, Martin; Palomera, Luis; Vilches, Carlos; García Marco, José A.; Pardo, Julián

    2016-01-01

    Mutational status of TP53 together with expression of wild-type (wt) IGHV represents the most widely accepted biomarkers, establishing a very poor prognosis in B-cell chronic lymphocytic leukemia (B-CLL) patients. Adoptive cell therapy using allogeneic HLA-mismatched Natural killer (NK) cells has emerged as an effective and safe alternative in the treatment of acute myeloid and lymphoid leukemias that do not respond to traditional therapies. We have described that allogeneic activated NK cells eliminate hematological cancer cell lines with multidrug resistance acquired by mutations in the apoptotic machinery. This effect depends on the activation protocol, being B-lymphoblastoid cell lines (LCLs) the most effective stimulus to activate NK cells. Here, we have further analyzed the molecular determinants involved in allogeneic NK cell recognition and elimination of B-CLL cells, including the expression of ligands of the main NK cell-activating receptors (NKG2D and NCRs) and HLA mismatch. We present preliminary data suggesting that B-CLL susceptibility significantly correlates with HLA mismatch between NK cell donor and B-CLL patient. Moreover, we show that the sensitivity of B-CLL cells to NK cells depends on the prognosis based on TP53 and IGHV mutational status. Cells from patients with worse prognosis (mutated TP53 and wt IGHV) are the most susceptible to activated NK cells. Hence, B-CLL prognosis may predict the efficacy of allogenic activated NK cells, and, thus, NK cell transfer represents a good alternative to treat poor prognosis B-CLL patients who present a very short life expectancy due to lack of effective treatments. PMID:27833611

  18. Advances in clinical NK cell studies: Donor selection, manufacturing and quality control

    PubMed Central

    Koehl, U.; Kalberer, C.; Spanholtz, J.; Lee, D. A.; Miller, J. S.; Cooley, S.; Lowdell, M.; Uharek, L.; Klingemann, H.; Curti, A.; Leung, W.; Alici, E.

    2016-01-01

    ABSTRACT Natural killer (NK) cells are increasingly used in clinical studies in order to treat patients with various malignancies. The following review summarizes platform lectures and 2013–2015 consortium meetings on manufacturing and clinical use of NK cells in Europe and United States. A broad overview of recent pre-clinical and clinical results in NK cell therapies is provided based on unstimulated, cytokine-activated, as well as genetically engineered NK cells using chimeric antigen receptors (CAR). Differences in donor selection, manufacturing and quality control of NK cells for cancer immunotherapies are described and basic recommendations are outlined for harmonization in future NK cell studies. PMID:27141397

  19. IL-15 promotes regulatory T cell function and protects against diabetes development in NK-depleted NOD mice.

    PubMed

    Xia, Jinxing; Liu, Wentao; Hu, Biliang; Tian, Zhigang; Yang, Yongguang

    2010-02-01

    IL-15, an anti-apoptotic cytokine, has been reported to promote the survival and function of NK cells and T cells, including regulatory T cells (Tregs). Here we examined the effect of repeated injections of IL-15 on the development of diabetes in NOD mice. Injection of recombinant murine IL-15, once a day for 2 weeks, neither inhibited nor accelerated diabetes development in untreated NOD mice. However, treatment with IL-15 significantly reduced the incidence and delayed the onset of diabetes in NOD mice that were depleted of NK cells, while NK cell depletion alone had no protection against the disease development. The protective effect in IL-15-treated, NK cell-depleted NOD mice was associated with an increase in immunosuppressive activity of CD4(+)CD25(+) Tregs. IL-15 also enhanced Foxp3 expression in CD4(+)CD25(+) cells in an in vitro culture system, and such an effect of IL-15 was abrogated by IL-15-activated NK cells. Inhibition of IL-15-induced Foxp3 expression by IL-15-activated NK cells likely resulted from their IFN-gamma production, as recombinant IFN-gamma, or the culture supernatant of IL-15-activated wild-type mouse NK cells but not of IL-15-activated IFN-gamma-deficient NK cells, mediated a similar inhibition. IFN-gamma also diminished the stimulatory effect of IL-15 on Treg function in vitro. These results indicate that IL-15 has the potential to promote Treg function and protect against diabetes development in NOD mice, but such an activity can be eliminated by simultaneous activation of NK cells in IL-15-treated mice.

  20. Aspergillus fumigatus responds to natural killer (NK) cells with upregulation of stress related genes and inhibits the immunoregulatory function of NK cells

    PubMed Central

    Schneider, Andreas; Blatzer, Michael; Posch, Wilfried; Schubert, Ralf; Lass-Flörl, Cornelia; Schmidt, Stanislaw; Lehrnbecher, Thomas

    2016-01-01

    Natural Killer (NK) cells are active against Aspergillus fumigatus, which in turn is able to impair the host defense. Unfortunately, little is known on the mutual interaction of NK cells and A. fumigatus. We coincubated human NK cells with A. fumigatus hyphae and assessed the gene expression and protein concentration of selected molecules. We found that A. fumigatus up-regulates the gene expression of pro-inflammatory molecules in NK cells, but inhibited the release of these molecules resulting in intracellular accumulation and limited extracellular availability. A. fumigatus down-regulatedmRNA levels of perforin in NK cells, but increased its intra- and extracellular protein concentration. The gene expression of stress related molecules of A. fumigatus such as heat shock protein hsp90 was up-regulated by human NK cells. Our data characterize for the first time the immunosuppressive effect of A. fumigatus on NK cells and may help to develop new therapeutic antifungal strategies. PMID:27738337

  1. Enhancement of anti-leukemia activity of NK cells in vitro and in vivo by inhibition of leukemia cell-induced NK cell damage

    PubMed Central

    Arriga, Roberto; Caratelli, Sara; Coppola, Andrea; Spagnoli, Giulio Cesare; Venditti, Adriano; Amadori, Sergio; Lanzilli, Giulia; Lauro, Davide; Palomba, Patrizia; Sconocchia, Tommaso; Del Principe, Maria Ilaria; Maurillo, Luca; Buccisano, Francesco; Capuani, Barbara; Ferrone, Soldano; Sconocchia, Giuseppe

    2016-01-01

    Acute myeloid leukemia (AML) cells induce, in vitro, NK cell abnormalities (NKCAs) including apoptosis and activating receptor down-regulation. The potential negative impact of AML cells on the therapeutic efficacy of NK cell-based strategies prompted us to analyze the mechanisms underlying NKCAs and to develop approaches to protect NK cells from NKCAs. NKCA induction by the AML leukemia cells target a subpopulation of peripheral blood NK cells and is interleukin-2 independent but is abrogated by a long-term culture of NK (LTNK) cells at 37°C. LTNK cells displayed a significantly enhanced ability to damage AML cells in vitro and inhibited the subcutaneous growth of ML-2 cells grafted into CB17 SCID mice. Actinomycin D restored the susceptibility of LTNK cells to NKCAs while TAPI-0, a functional analog of the tissue inhibitor of metalloproteinase (TIMP) 3, inhibits ML-2 cell-induced NKCAs suggesting that the generation of NK cell resistance to NKCAs involves RNA transcription and metalloproteinase (MPP) inactivation. This conclusion is supported by the reduced susceptibility to AML cell-induced NKCAs of LTNK cells in which TIMP3 gene and protein are over-expressed. This information may contribute to the rational design of targeted strategies to enhance the efficacy of NK cell-based-immunotherapy of AML with haploidentical NK cells. PMID:26655503

  2. Enhancement of anti-leukemia activity of NK cells in vitro and in vivo by inhibition of leukemia cell-induced NK cell damage.

    PubMed

    Arriga, Roberto; Caratelli, Sara; Coppola, Andrea; Spagnoli, Giulio Cesare; Venditti, Adriano; Amadori, Sergio; Lanzilli, Giulia; Lauro, Davide; Palomba, Patrizia; Sconocchia, Tommaso; Del Principe, Maria Ilaria; Maurillo, Luca; Buccisano, Francesco; Capuani, Barbara; Ferrone, Soldano; Sconocchia, Giuseppe

    2016-01-12

    Acute myeloid leukemia (AML) cells induce, in vitro, NK cell abnormalities (NKCAs) including apoptosis and activating receptor down-regulation. The potential negative impact of AML cells on the therapeutic efficacy of NK cell-based strategies prompted us to analyze the mechanisms underlying NKCAs and to develop approaches to protect NK cells from NKCAs. NKCA induction by the AML leukemia cells target a subpopulation of peripheral blood NK cells and is interleukin-2 independent but is abrogated by a long-term culture of NK (LTNK) cells at 37°C. LTNK cells displayed a significantly enhanced ability to damage AML cells in vitro and inhibited the subcutaneous growth of ML-2 cells grafted into CB17 SCID mice. Actinomycin D restored the susceptibility of LTNK cells to NKCAs while TAPI-0, a functional analog of the tissue inhibitor of metalloproteinase (TIMP) 3, inhibits ML-2 cell-induced NKCAs suggesting that the generation of NK cell resistance to NKCAs involves RNA transcription and metalloproteinase (MPP) inactivation. This conclusion is supported by the reduced susceptibility to AML cell-induced NKCAs of LTNK cells in which TIMP3 gene and protein are over-expressed. This information may contribute to the rational design of targeted strategies to enhance the efficacy of NK cell-based-immunotherapy of AML with haploidentical NK cells.

  3. NK cells and T cells cooperate during the clinical course of colorectal cancer

    PubMed Central

    Sconocchia, Giuseppe; Eppenberger, Serenella; Spagnoli, Giulio C; Tornillo, Luigi; Droeser, Raoul; Caratelli, Sara; Ferrelli, Francesca; Coppola, Andrea; Arriga, Roberto; Lauro, Davide; Iezzi, Giandomenica; Terracciano, Luigi; Ferrone, Soldano

    2014-01-01

    Recent evidence suggests that natural killer (NK) cells are typically defective in infiltrating solid tumors, with the exception of gastrointestinal stromal tumors (GIST). Interestingly, however, infrequently infiltrating NK cells do not appear to have a direct effect on tumor progression. Here, prompted by the recent evidence that NK cell and T cell crosstalk may trigger, or enhance, tumor antigen-specific immune responses, we have tested the clinical significance of this reciprocal signaling. To this end, a tissue microarray constructed with 1410 colorectal carcinoma (CRC) patient specimens was stained with NK and T cell antigen-specific monoclonal antibodies, utilizing the immunoperoxidase staining technique. Cut-off scores for positive (>4 NK cells) and negative (≤4 NK cells) NK cell CRC patient samples were determined using receiver operating characteristic curve analysis. Using this approach, NK cells were detected in 423 (30%) of the 1410 CRC specimens evaluated. The number of NK cells was >4 in only 132 (9%) of CRC samples. Correlation of the immunohistochemical staining results together with analysis of the clinical course of the disease revealed that the infiltration of colorectal tumors with both NK cells and CD8+ T cells is associated with prolonged patient survival. In contrast, infiltration of tumors with NK cells in combination with CD3+ and CD4+ T lymphocytes had no detectable effect on the clinical course of the disease. These results suggest that NK cell and CD8+ T cell crosstalk in the tumor microenvironment may benefit patient outcome and further, that the enumeration of infiltrating NK and CD8+ T cells in CRC tumors may provide useful prognostic information. PMID:25610741

  4. Microchip Screening Platform for Single Cell Assessment of NK Cell Cytotoxicity.

    PubMed

    Guldevall, Karolin; Brandt, Ludwig; Forslund, Elin; Olofsson, Karl; Frisk, Thomas W; Olofsson, Per E; Gustafsson, Karin; Manneberg, Otto; Vanherberghen, Bruno; Brismar, Hjalmar; Kärre, Klas; Uhlin, Michael; Önfelt, Björn

    2016-01-01

    Here, we report a screening platform for assessment of the cytotoxic potential of individual natural killer (NK) cells within larger populations. Human primary NK cells were distributed across a silicon-glass microchip containing 32,400 individual microwells loaded with target cells. Through fluorescence screening and automated image analysis, the numbers of NK and live or dead target cells in each well could be assessed at different time points after initial mixing. Cytotoxicity was also studied by time-lapse live-cell imaging in microwells quantifying the killing potential of individual NK cells. Although most resting NK cells (≈75%) were non-cytotoxic against the leukemia cell line K562, some NK cells were able to kill several (≥3) target cells within the 12-h long experiment. In addition, the screening approach was adapted to increase the chance to find and evaluate serial killing NK cells. Even if the cytotoxic potential varied between donors, it was evident that a small fraction of highly cytotoxic NK cells were responsible for a substantial portion of the killing. We demonstrate multiple assays where our platform can be used to enumerate and characterize cytotoxic cells, such as NK or T cells. This approach could find use in clinical applications, e.g., in the selection of donors for stem cell transplantation or generation of highly specific and cytotoxic cells for adoptive immunotherapy.

  5. The TGF-β/SMAD pathway is an important mechanism for NK cell immune evasion in childhood B-acute lymphoblastic leukemia.

    PubMed

    Rouce, R H; Shaim, H; Sekine, T; Weber, G; Ballard, B; Ku, S; Barese, C; Murali, V; Wu, M-F; Liu, H; Shpall, E J; Bollard, C M; Rabin, K R; Rezvani, K

    2016-04-01

    Natural killer (NK) cells are key components of the innate immune system, providing potent antitumor immunity. Here, we show that the tumor growth factor-β (TGF-β)/SMAD signaling pathway is an important mechanism for NK cell immune evasion in childhood B-acute lymphoblastic leukemia (ALL). We characterized NK cells in 50 consecutive children with B-ALL at diagnosis, end induction and during maintenance therapy compared with age-matched controls. ALL-NK cells at diagnosis had an inhibitory phenotype associated with impaired function, most notably interferon-γ production and cytotoxicity. By maintenance therapy, these phenotypic and functional abnormalities partially normalized; however, cytotoxicity against autologous blasts remained impaired. We identified ALL-derived TGF-β1 to be an important mediator of leukemia-induced NK cell dysfunction. The TGF-β/SMAD signaling pathway was constitutively activated in ALL-NK cells at diagnosis and end induction when compared with healthy controls and patients during maintenance therapy. Culture of ALL blasts with healthy NK cells induced NK dysfunction and an inhibitory phenotype, mediated by activation of the TGF-β/SMAD signaling pathway, and abrogated by blocking TGF-β. These data indicate that by regulating the TGF-β/SMAD pathway, ALL blasts induce changes in NK cells to evade innate immune surveillance, thus highlighting the importance of developing novel therapies to target this inhibitory pathway and restore antileukemic cytotoxicity.

  6. Absence of circulating natural killer (NK) cells in a child with erythrophagocytic lymphohistiocytosis lacking NK cell activity

    SciTech Connect

    Kawai, H.; Komiyama, A.; Aoyama, K.; Miyagawa, Y.; Akabane, T.

    1988-06-01

    A 5-year-old girl who was diagnosed as having erythrophagocytic lymphohistiocytosis died at age 9 years. Peripheral lymphocytes from the patient persistently lacked natural killer (NK) cell activity during the 4-year observation period: the percent lysis values as measured by a 4-hr /sup 51/Cr release assay at a 40:1 effector:target ratio were below 1.0% against K562 and Molt-4 cells as compared with the normal lymphocyte value (mean +/- SD) of 46.2% +/- 5.8% and 43.9% +/- 6.7%, respectively. The patient's lymphocytes never developed NK cell activity by their incubation with target cells for longer time periods or by their stimulation with interferon-alpha, interleukin-2, or polyinosinic-polycytidilic acid. Single cell-in-agarose assay showed the absence of target-binding cells (TBCs): TBC numbers were below 0.3% as compared with the normal lymphocyte value of 8.1% +/- 1.3% (mean +/- SD). Flow cytometry showed a marked decrease in Leu-7+ cells (1.7%) and the absence of Leu-11+ cells (0.4%) in the peripheral blood. These results first demonstrate a case of erythrophagocytic lymphohistiocytosis in which there is the lack of NK cell activity due to the absence of circulating NK cells.

  7. NK cells with KIR2DS2 immunogenotype have a functional activation advantage to efficiently kill glioblastoma and prolong animal survival.

    PubMed

    Gras Navarro, Andrea; Kmiecik, Justyna; Leiss, Lina; Zelkowski, Mateusz; Engelsen, Agnete; Bruserud, Øystein; Zimmer, Jacques; Enger, Per Øyvind; Chekenya, Martha

    2014-12-15

    Glioblastomas (GBMs) are lethal brain cancers that are resistant to current therapies. We investigated the cytotoxicity of human allogeneic NK cells against patient-derived GBM in vitro and in vivo, as well as mechanisms mediating their efficacy. We demonstrate that KIR2DS2 immunogenotype NK cells were more potent killers, notwithstanding the absence of inhibitory killer Ig-like receptor (KIR)-HLA ligand mismatch. FACS-sorted and enriched KIR2DS2(+) NK cell subpopulations retained significantly high levels of CD69 and CD16 when in contact with GBM cells at a 1:1 ratio and highly expressed CD107a and secreted more soluble CD137 and granzyme A. In contrast, KIR2DS2(-) immunogenotype donor NK cells were less cytotoxic against GBM and K562, and, similar to FACS-sorted or gated KIR2DS2(-) NK cells, significantly diminished CD16, CD107a, granzyme A, and CD69 when in contact with GBM cells. Furthermore, NK cell-mediated GBM killing in vitro depended upon the expression of ligands for the activating receptor NKG2D and was partially abrogated by Ab blockade. Treatment of GBM xenografts in NOD/SCID mice with NK cells from a KIR2DS2(+) donor lacking inhibitory KIR-HLA ligand mismatch significantly prolonged the median survival to 163 d compared with vehicle controls (log-rank test, p = 0.0001), in contrast to 117.5 d (log-rank test, p = 0.0005) for NK cells with several inhibitory KIR-HLA ligand mismatches but lacking KIR2DS2 genotype. Significantly more CD56(+)CD16(+) NK cells from a KIR2DS2(+) donor survived in nontumor-bearing brains 3 wk after infusion compared with KIR2DS2(-) NK cells, independent of their proliferative capacity. In conclusion, KIR2DS2 identifies potent alloreactive NK cells against GBM that are mediated by commensurate, but dominant, activating signals.

  8. Induced Human Decidual NK-Like Cells Improve Utero-Placental Perfusion in Mice

    PubMed Central

    Pernicone, Elizabeth; Korkes, Henri A.; Burke, Suzanne D.; Rajakumar, Augustine; Thadhani, Ravi I.; Roberts, Drucilla J.; Bhasin, Manoj; Karumanchi, S. Ananth

    2016-01-01

    Decidual NK (dNK) cells, a distinct type of NK cell, are thought to regulate uterine spiral artery remodeling, a process that allows for increased blood delivery to the fetal-placental unit. Impairment of uterine spiral artery remodeling is associated with decreased placental perfusion, increased uterine artery resistance, and obstetric complications such as preeclampsia and intrauterine growth restriction. Ex vivo manipulation of human peripheral blood NK (pNK) cells by a combination of hypoxia, TGFß-1 and 5-aza-2’-deoxycytidine yields cells with phenotypic and in vitro functional similarities to dNK cells, called idNK cells. Here, gene expression profiling shows that CD56Bright idNK cells derived ex vivo from human pNK cells, and to a lesser extent CD56Dim idNK cells, are enriched in the gene expression signature that distinguishes dNK cells from pNK cells. When injected into immunocompromised pregnant mice with elevated uterine artery resistance, idNK cells homed to the uterus and reduced the uterine artery resistance index, suggesting improved placental perfusion. PMID:27736914

  9. NK Cells Preferentially Target Tumor Cells with a Cancer Stem Cell Phenotype.

    PubMed

    Ames, Erik; Canter, Robert J; Grossenbacher, Steven K; Mac, Stephanie; Chen, Mingyi; Smith, Rachel C; Hagino, Takeshi; Perez-Cunningham, Jessica; Sckisel, Gail D; Urayama, Shiro; Monjazeb, Arta M; Fragoso, Ruben C; Sayers, Thomas J; Murphy, William J

    2015-10-15

    Increasing evidence supports the hypothesis that cancer stem cells (CSCs) are resistant to antiproliferative therapies, able to repopulate tumor bulk, and seed metastasis. NK cells are able to target stem cells as shown by their ability to reject allogeneic hematopoietic stem cells but not solid tissue grafts. Using multiple preclinical models, including NK coculture (autologous and allogeneic) with multiple human cancer cell lines and dissociated primary cancer specimens and NK transfer in NSG mice harboring orthotopic pancreatic cancer xenografts, we assessed CSC viability, CSC frequency, expression of death receptor ligands, and tumor burden. We demonstrate that activated NK cells are capable of preferentially killing CSCs identified by multiple CSC markers (CD24(+)/CD44(+), CD133(+), and aldehyde dehydrogenase(bright)) from a wide variety of human cancer cell lines in vitro and dissociated primary cancer specimens ex vivo. We observed comparable effector function of allogeneic and autologous NK cells. We also observed preferential upregulation of NK activation ligands MICA/B, Fas, and DR5 on CSCs. Blocking studies further implicated an NKG2D-dependent mechanism for NK killing of CSCs. Treatment of orthotopic human pancreatic cancer tumor-bearing NSG mice with activated NK cells led to significant reductions in both intratumoral CSCs and tumor burden. Taken together, these data from multiple preclinical models, including a strong reliance on primary human cancer specimens, provide compelling preclinical evidence that activated NK cells preferentially target cancer cells with a CSC phenotype, highlighting the translational potential of NK immunotherapy as part of a combined modality approach for refractory solid malignancies.

  10. Acute GVHD in patients receiving IL-15/4-1BBL activated NK cells following T-cell–depleted stem cell transplantation

    PubMed Central

    Shah, Nirali N.; Baird, Kristin; Delbrook, Cynthia P.; Fleisher, Thomas A.; Kohler, Mark E.; Rampertaap, Shakuntala; Lemberg, Kimberly; Hurley, Carolyn K.; Kleiner, David E.; Merchant, Melinda S.; Pittaluga, Stefania; Sabatino, Marianna; Stroncek, David F.; Wayne, Alan S.; Zhang, Hua; Fry, Terry J.

    2015-01-01

    Natural killer (NK) cells can enhance engraftment and mediate graft-versus-leukemia following allogeneic hematopoietic stem cell transplantation (HSCT), but the potency of graft-versus-leukemia mediated by naturally reconstituting NK cells following HSCT is limited. Preclinical studies demonstrate that activation of NK cells using interleukin-15 (IL-15) plus 4-1BBL upregulates activating receptor expression and augments killing capacity. In an effort to amplify the beneficial effects of NK cells post-HSCT, we conducted a first-in-human trial of adoptive transfer of donor-derived IL-15/4-1BBL–activated NK cells (aNK-DLI) following HLA-matched, T-cell–depleted (1-2 × 104 T cells/kg) nonmyeloablative peripheral blood stem cell transplantation in children and young adults with ultra-high-risk solid tumors. aNK-DLI were CD3+-depleted, CD56+-selected lymphocytes, cultured for 9 to 11 days with recombinant human IL-15 plus 4-1BBL+IL-15Rα+ artificial antigen-presenting cells. aNK-DLI demonstrated potent killing capacity and displayed high levels of activating receptor expression. Five of 9 transplant recipients experienced acute graft-versus-host disease (GVHD) following aNK-DLI, with grade 4 GVHD observed in 3 subjects. GVHD was more common in matched unrelated donor vs matched sibling donor recipients and was associated with higher donor CD3 chimerism. Given that the T-cell dose was below the threshold required for GVHD in this setting, we conclude that aNK-DLI contributed to the acute GVHD observed, likely by augmenting underlying T-cell alloreactivity. This trial was registered at www.clinicaltrials.gov as #NCT01287104. PMID:25452614

  11. Immunomodulatory effect of prednisolone (PRD) induced soluble suppressor factor(s) (PRD-SSF) on natural killer (NK) cell activity

    SciTech Connect

    Nair, M.P.N.; Cilik, J.M.; Schwartz, S.A.

    1986-03-01

    The authors have previously reported that peripheral blood lymphocytes precultured for 24 hrs with PRD showed significant suppression of their NK activity. Purified HNK-1/sup +/ lymphocytes were treated either directly with PRD or with supernates from allogeneic lymphocytes precultured with 10/sup -6/ to 10/sup -9/M PRD and examined for any inhibition of NK activity. For the NK assay K562 and U937 cell lines were used as targets in a 4 hr /sup 51/Cr release assay. HNK-1/sup +/ lymphocytes precultured with PRD showed significantly lower level of NK activity. In a single cell assay, both HNK-1/sup +/ and HNK-1/sup -/ subpopulations of PBL precultured with PRD also suppressed the target binding and lytic capacity of allogeneic fresh large granular lymphocytes, suggesting that NK cells/T cells or their precursors can be stimulated by PRD to inhibit NK activity. PBL precultured with increasing concentrations of culture supernates containing PRD-SSF showed a dose dependent inhibitory effect of their NK activity. This data suggest that PRD activated suppressor cells function through the release of soluble mediators. These findings may be of clinical significance to patients receiving corticosteroids for a variety of disorders including malignant, autoimmune and atopic diseases.

  12. Maternal obesity drives functional alterations in uterine NK cells

    PubMed Central

    Perdu, Sofie; Castellana, Barbara; Kim, Yoona; Chan, Kathy; DeLuca, Lauren; Beristain, Alexander G.

    2016-01-01

    Over one-fifth of North American women of childbearing age are obese, putting these women at risk for a variety of detrimental chronic diseases. In addition, obesity increases the risk for developing major complications during pregnancy. The mechanisms by which obesity contributes to pregnancy complications and loss remain unknown. Increasing evidence indicates that obesity results in major changes to adipose tissue immune cell composition and function; whether or not obesity also affects immune function in the uterus has not been explored. Here we investigated the effect of obesity on uterine natural killer (uNK) cells, which are essential for uterine artery remodeling and placental development. Using a cohort of obese or lean women, we found that obesity led to a significant reduction in uNK cell numbers accompanied with impaired uterine artery remodeling. uNK cells isolated from obese women had altered expression of genes and pathways associated with extracellular matrix remodeling and growth factor signaling. Specifically, uNK cells were hyper-responsive to PDGF, resulting in overexpression of decorin. Functionally, decorin strongly inhibited placental development by limiting trophoblast survival. Together, these findings establish a potentially new link between obesity and poor pregnancy outcomes, and indicate that obesity-driven changes to uterine-resident immune cells critically impair placental development. PMID:27699222

  13. Development of Three Different NK Cell Subpopulations during Immune Reconstitution after Pediatric Allogeneic Hematopoietic Stem Cell Transplantation: Prognostic Markers in GvHD and Viral Infections.

    PubMed

    Huenecke, Sabine; Cappel, Claudia; Esser, Ruth; Pfirrmann, Verena; Salzmann-Manrique, Emilia; Betz, Sibille; Keitl, Eileen; Banisharif-Dehkordi, Julia; Bakhtiar, Shahrzad; Königs, Christoph; Jarisch, Andrea; Soerensen, Jan; Ullrich, Evelyn; Klingebiel, Thomas; Bader, Peter; Bremm, Melanie

    2017-01-01

    Natural killer (NK) cells play an important role following allogeneic hematopoietic stem cell transplantation (HSCT) exerting graft-versus-leukemia/tumor effect and mediating pathogen-specific immunity. Although NK cells are the first donor-derived lymphocytes reconstituting post-HSCT, their distribution of CD56(++)CD16(-) (CD56(bright)), CD56(++)CD16(+) (CD56(intermediate=int)), and CD56(+)CD16(++) (CD56(dim)) NK cells is explicitly divergent from healthy adults, but to some extent comparable to the NK cell development in early childhood. The proportion of CD56(bright)/CD56(int)/CD56(dim) changed from 15/8/78% in early childhood to 6/4/90% in adults, respectively. Within this study, we first compared the NK cell reconstitution post-HSCT to reference values of NK cell subpopulations of healthy children. Afterward, we investigated the reconstitution of NK cell subpopulations post-HSCT in correlation to acute graft versus host disease (aGvHD) and chronic graft versus host disease (cGvHD) as well as to viral infections. Interestingly, after a HSCT follow-up phase of 12 months, the distribution of NK cell subpopulations largely matched the 50th percentile of the reference range for healthy individuals. Patients suffering from aGvHD and cGvHD showed a delayed reconstitution of NK cells. Remarkably, within the first 2 months post-HSCT, patients suffering from aGvHD had significantly lower levels of CD56(bright) NK cells compared to patients without viral infection or without graft versus host disease (GvHD). Therefore, the amount of CD56(bright) NK cells might serve as an early prognostic factor for GvHD development. Furthermore, a prolonged and elevated peak in CD56(int) NK cells seemed to be characteristic for the chronification of GvHD. In context of viral infection, a slightly lower CD56 and CD16 receptor expression followed by a considerable reduction in the absolute CD56(dim) NK cell numbers combined with reoccurrence of CD56(int) NK cells was observed. Our

  14. Development of Three Different NK Cell Subpopulations during Immune Reconstitution after Pediatric Allogeneic Hematopoietic Stem Cell Transplantation: Prognostic Markers in GvHD and Viral Infections

    PubMed Central

    Huenecke, Sabine; Cappel, Claudia; Esser, Ruth; Pfirrmann, Verena; Salzmann-Manrique, Emilia; Betz, Sibille; Keitl, Eileen; Banisharif-Dehkordi, Julia; Bakhtiar, Shahrzad; Königs, Christoph; Jarisch, Andrea; Soerensen, Jan; Ullrich, Evelyn; Klingebiel, Thomas; Bader, Peter; Bremm, Melanie

    2017-01-01

    Natural killer (NK) cells play an important role following allogeneic hematopoietic stem cell transplantation (HSCT) exerting graft-versus-leukemia/tumor effect and mediating pathogen-specific immunity. Although NK cells are the first donor-derived lymphocytes reconstituting post-HSCT, their distribution of CD56++CD16− (CD56bright), CD56++CD16+ (CD56intermediate=int), and CD56+CD16++ (CD56dim) NK cells is explicitly divergent from healthy adults, but to some extent comparable to the NK cell development in early childhood. The proportion of CD56bright/CD56int/CD56dim changed from 15/8/78% in early childhood to 6/4/90% in adults, respectively. Within this study, we first compared the NK cell reconstitution post-HSCT to reference values of NK cell subpopulations of healthy children. Afterward, we investigated the reconstitution of NK cell subpopulations post-HSCT in correlation to acute graft versus host disease (aGvHD) and chronic graft versus host disease (cGvHD) as well as to viral infections. Interestingly, after a HSCT follow-up phase of 12 months, the distribution of NK cell subpopulations largely matched the 50th percentile of the reference range for healthy individuals. Patients suffering from aGvHD and cGvHD showed a delayed reconstitution of NK cells. Remarkably, within the first 2 months post-HSCT, patients suffering from aGvHD had significantly lower levels of CD56bright NK cells compared to patients without viral infection or without graft versus host disease (GvHD). Therefore, the amount of CD56bright NK cells might serve as an early prognostic factor for GvHD development. Furthermore, a prolonged and elevated peak in CD56int NK cells seemed to be characteristic for the chronification of GvHD. In context of viral infection, a slightly lower CD56 and CD16 receptor expression followed by a considerable reduction in the absolute CD56dim NK cell numbers combined with reoccurrence of CD56int NK cells was observed. Our results suggest that a precise

  15. Activated hepatic stellate cells impair NK cell anti-fibrosis capacity through a TGF-β-dependent emperipolesis in HBV cirrhotic patients.

    PubMed

    Shi, Jijing; Zhao, Juanjuan; Zhang, Xin; Cheng, Yongqian; Hu, Jinhua; Li, Yuanyuan; Zhao, Xin; Shang, Qinghua; Sun, Yanling; Tu, Bo; Shi, Lei; Gao, Bin; Wang, Fu-Sheng; Zhang, Zheng

    2017-03-14

    Natural killer (NK) cells can induce liver fibrosis remission by killing hepatic stellate cells (HSCs) and producing interferon (IFN)-γ in a mouse model; however, their anti-fibrotic immune-characteristics and regulatory mechanisms by HSCs remain to be determined, especially in livers from HBV-infected liver cirrhosis (LC) patients. We analyzed frequency, phenotype and anti-fibrotic function of hepatic and peripheral NK subsets in 43 HBV-LC patients. We found that hepatic NK subsets from LC patients displayed a decreased frequency, activation status and anti-fibrotic activity compared with those from chronic hepatitis B patients, which were mainly mediated by increased intrahepatic tumour-growth factor (TGF)-β because blockade of TGF-β significantly reversed NK anti-fibrotic function in vitro. In vivo, hepatic NK cells were enriched in proximity to the α-smooth muscle actin (α-SMA+) area within mild fibrosis regions; while in severe fibrotic areas, they were either directly attached to or separated from the α-SMA+ region. NK cells from LC patients could enter HSCs to form emperipolesis (a cell-in-cell structure) and become apoptotic; anti-TGF-β treatment ameliorated this emperipolesis. This finding suggested a novel mechanism by which activated HSCs impair NK cells' anti-fibrosis capacity through a TGF-β-dependent emperipolesis in LC patients, providing an anti-fibrotic rational by enhancing NK cell activity.

  16. MUC16 provides immune protection by inhibiting synapse formation between NK and ovarian tumor cells

    PubMed Central

    2010-01-01

    Background Cancer cells utilize a variety of mechanisms to evade immune detection and attack. Effective immune detection largely relies on the formation of an immune synapse which requires close contact between immune cells and their targets. Here, we show that MUC16, a heavily glycosylated 3-5 million Da mucin expressed on the surface of ovarian tumor cells, inhibits the formation of immune synapses between NK cells and ovarian tumor targets. Our results indicate that MUC16-mediated inhibition of immune synapse formation is an effective mechanism employed by ovarian tumors to evade immune recognition. Results Expression of low levels of MUC16 strongly correlated with an increased number of conjugates and activating immune synapses between ovarian tumor cells and primary naïve NK cells. MUC16-knockdown ovarian tumor cells were more susceptible to lysis by primary NK cells than MUC16 expressing controls. This increased lysis was not due to differences in the expression levels of the ligands for the activating receptors DNAM-1 and NKG2D. The NK cell leukemia cell line (NKL), which does not express KIRs but are positive for DNAM-1 and NKG2D, also conjugated and lysed MUC16-knockdown cells more efficiently than MUC16 expressing controls. Tumor cells that survived the NKL challenge expressed higher levels of MUC16 indicating selective lysis of MUC16low targets. The higher csMUC16 levels on the NKL resistant tumor cells correlated with more protection from lysis as compared to target cells that were never exposed to the effectors. Conclusion MUC16, a carrier of the tumor marker CA125, has previously been shown to facilitate ovarian tumor metastasis and inhibits NK cell mediated lysis of tumor targets. Our data now demonstrates that MUC16 expressing ovarian cancer cells are protected from recognition by NK cells. The immune protection provided by MUC16 may lead to selective survival of ovarian cancer cells that are more efficient in metastasizing within the peritoneal

  17. Intratumoral delivery of CpG-conjugated anti-MUC1 antibody enhances NK cell anti-tumor activity

    PubMed Central

    Schettini, Jorge; Kidiyoor, Amritha; Besmer, Dahlia M.; Tinder, Teresa L.; Roy, Lopamudra Das; Lustgarten, Joseph; Gendler, Sandra J.

    2013-01-01

    Monoclonal antibodies (mAbs) against tumor-associated antigens are useful anticancer agents. Antibody-dependent cellular cytotoxicity (ADCC) is one of the major mechanisms responsible for initiating natural killer cell (NK)-mediated killing of tumors. However, the regulation of ADCC via NK cells is poorly understood. We have investigated the cytolytic activity of NK cells against pancreatic cancer cells that were coated with an antibody directed against the human tumor antigen, Mucin-1 designated HMFG-2, either alone or conjugated to CpG oligodeoxynucleotide (CpG ODN). Conjugated antibodies were tested for their ability to elicit ADCC in vitro and in vivo against pancreatic cancer cells. NK cells cultured in the presence of immobilized CpG ODN, HMFG-2 Ab, or CpG ODN-conjugated HMFG-2 Ab were able to up-regulate perforin similarly. Interestingly, a significant higher ADCC was observed when CpG ODN-conjugated HMFG-2-coated tumor cells were co-cultured with NK cells compared to unconjugated HMFG-2 Ab or CpG ODN alone. Moreover, MyD88-deficient NK cells can perform ADCC in vitro. Furthermore, intratumoral injections of CpG ODN-conjugated HMFG-2 induced a significant reduction in tumor burden in vivo in an established model of pancreatic tumor in nude mice compared to CpG ODN or the HMFG-2 alone. Depletion of macrophages or NK cells before treatment confirmed that both cells were required for the anti-tumor response in vivo. Results also suggest that CpG ODN and HMFG-2 Ab could be sensed by NK cells on the mAb-coated tumor cells triggering enhanced ADCC in vitro and in vivo. PMID:22543528

  18. NK Cells Help Induce Anti-Hepatitis B Virus CD8+ T Cell Immunity in Mice.

    PubMed

    Zheng, Meijuan; Sun, Rui; Wei, Haiming; Tian, Zhigang

    2016-05-15

    Although recent clinical studies demonstrate that NK cell function is impaired in hepatitis B virus (HBV)-persistent patients, whether or how NK cells play a role in anti-HBV adaptive immunity remains to be explored. Using a mouse model mimicking acute HBV infection by hydrodynamic injection of an HBV plasmid, we observed that although serum hepatitis B surface Ag and hepatitis B envelope Ag were eliminated within 3 to 4 wk, HBV might persist for >8 wk in CD8(-/-) mice and that adoptive transfer of anti-HBV CD8(+) T cells restored the ability to clear HBV in HBV-carrier Rag1(-/-) mice. These results indicate that CD8(+) T cells are critical in HBV elimination. Furthermore, NK cells increased IFN-γ production after HBV plasmid injection, and NK cell depletion led to significantly increased HBV persistence along with reduced frequency of hepatitis B core Ag-specific CD8(+) T cells. Adoptive transfer of IFN-γ-sufficient NK cells restored donor CD8(+) T cell function, indicating that NK cells positively regulated CD8(+) T cells via secreting IFN-γ. We also observed that NK cell depletion correlated with decreased effector memory CD8(+) T cell frequencies. Importantly, adoptive transfer experiments showed that NK cells were involved in anti-HBV CD8(+) T cell recall responses. Moreover, DX5(+)CD49a(-) conventional, but not DX5(-)CD49a(+) liver-resident, NK cells were involved in improving CD8(+) T cell responses against HBV. Overall, the current study reveals that NK cells, especially DX5(+)CD49a(-) conventional NK cells, promote the antiviral activity of CD8(+) T cell responses via secreting IFN-γ in a mouse model mimicking acute HBV infection.

  19. Human NK Cell Subsets in Pregnancy and Disease: Toward a New Biological Complexity.

    PubMed

    Cristiani, Costanza Maria; Palella, Eleonora; Sottile, Rosa; Tallerico, Rossana; Garofalo, Cinzia; Carbone, Ennio

    2016-01-01

    In humans, NK cells are mainly identified by the surface expression levels of CD56 and CD16, which differentiate between five functionally different NK cell subsets. However, nowadays NK cells are considered as a more heterogeneous population formed by various subsets differing in function, surface phenotype, and anatomic localization. In human CMV- and hantaviruses-infected subjects, an increased frequency of a NKG2A(-)CD57(+)NKG2C(+) NK cell subset has been observed, while the phenotype of the NK cell subpopulation associated with cancer may vary according to the specific kind of tumor and its anatomical location. The healthy human lymph nodes contain mainly the CD56(bright) NK cell subset while in melanoma metastatic lymph nodes the CD56(dim)CD57(+)KIR(+)CCR7(+) NK cell subpopulation prevails. The five NK cell subpopulations are found in breast cancer patients, where they differ for expression pattern of chemokine receptors, maturation stage, functional capabilities. In pregnancy, uterine NK cells show a prevalence of the CD56(bright)CD16(-) NK cell compartment, whose activity is influenced by KIRs repertoire. This NK cell subset's super specialization could be explained by (i) the expansion of single mature CD56(dim) clones, (ii) the recruitment and maturation of CD56(bright) NK cells through specific stimuli, and (iii) the in situ development of tumor-resident NK cells from tissue-resident CD56(bright) NK cells independently of the circulating NK cell compartment. This new and unexpected biological feature of the NK cell compartment could be an important source of new biomarkers to improve patients' diagnosis.

  20. Human NK Cell Subsets in Pregnancy and Disease: Toward a New Biological Complexity

    PubMed Central

    Cristiani, Costanza Maria; Palella, Eleonora; Sottile, Rosa; Tallerico, Rossana; Garofalo, Cinzia; Carbone, Ennio

    2016-01-01

    In humans, NK cells are mainly identified by the surface expression levels of CD56 and CD16, which differentiate between five functionally different NK cell subsets. However, nowadays NK cells are considered as a more heterogeneous population formed by various subsets differing in function, surface phenotype, and anatomic localization. In human CMV- and hantaviruses-infected subjects, an increased frequency of a NKG2A−CD57+NKG2C+ NK cell subset has been observed, while the phenotype of the NK cell subpopulation associated with cancer may vary according to the specific kind of tumor and its anatomical location. The healthy human lymph nodes contain mainly the CD56bright NK cell subset while in melanoma metastatic lymph nodes the CD56dimCD57+KIR+CCR7+ NK cell subpopulation prevails. The five NK cell subpopulations are found in breast cancer patients, where they differ for expression pattern of chemokine receptors, maturation stage, functional capabilities. In pregnancy, uterine NK cells show a prevalence of the CD56brightCD16− NK cell compartment, whose activity is influenced by KIRs repertoire. This NK cell subset’s super specialization could be explained by (i) the expansion of single mature CD56dim clones, (ii) the recruitment and maturation of CD56bright NK cells through specific stimuli, and (iii) the in situ development of tumor-resident NK cells from tissue-resident CD56bright NK cells independently of the circulating NK cell compartment. This new and unexpected biological feature of the NK cell compartment could be an important source of new biomarkers to improve patients’ diagnosis. PMID:28082990

  1. Peripheral NK cell phenotypes: multiple changing of faces of an adapting, developing cell.

    PubMed

    Perussia, Bice; Chen, Yingying; Loza, Matthew J

    2005-02-01

    We have defined the existence of developmental relationships among human peripheral NK cells with distinct phenotypic and functional characteristics. These findings closely parallel the changes that occur in vivo during NK cell development, and in vitro in experimental culture systems supporting NK cell generation from hematopoietic progenitors. These new insights provide a simplified framework to understand NK cell immunobiology and the cellular bases for their roles in innate immunity, initiation and maintenance of immune responses via regulation of adaptive and accessory cell functions, and immune pathologies.

  2. The molecular landscape of antibody-mediated kidney transplant rejection: evidence for NK involvement through CD16a Fc receptors.

    PubMed

    Venner, J M; Hidalgo, L G; Famulski, K S; Chang, J; Halloran, P F

    2015-05-01

    The recent recognition that antibody-mediated rejection (ABMR) is the major cause of kidney transplant loss creates strong interest in its pathogenesis. We used microarray analysis of kidney transplant biopsies to identify the changes in pure ABMR. We found that the ABMR transcript changes in the initial Discovery Set were strongly conserved in a subsequent Validation Set. In the Combined Set of 703 biopsies, 2603 transcripts were significantly changed (FDR < 0.05) in ABMR versus all other biopsies. In cultured cells, the transcripts strongly associated with ABMR were expressed in endothelial cells, e.g. cadherins CDH5 and CDH13; IFNG-treated endothelial cells, e.g. phospholipase PLA1A and chemokine CXCL11; or NK cells, e.g. cytotoxicity molecules granulysin (GNLY) and FGFBP2. Other ABMR transcripts were expressed in normal kidney but not cell lines, either increased e.g. Duffy chemokine receptor (DARC) or decreased e.g. sclerostin (SOST). Pathway analysis of ABMR transcripts identified angiogenesis, with roles for angiopoietin and vascular endothelial growth factors; leukocyte-endothelial interactions; and NK signaling, including evidence for CD16a Fc receptor signaling elements shared with T cells. These data support a model of ABMR involving injury-repair in the microcirculation induced by cognate recognition involving antibody and CD16a, triggering IFNG release and antibody-dependent NK cell-mediated cytotoxicity.

  3. NK cell effector functions in a Chédiak-Higashi patient undergoing cord blood transplantation: Effects of in vitro treatment with IL-2.

    PubMed

    Cifaldi, Loredana; Pinto, Rita Maria; Rana, Ippolita; Caniglia, Maurizio; Angioni, Adriano; Petrocchi, Stefano; Cancrini, Caterina; Cursi, Laura; Palumbo, Giuseppe; Zingoni, Alessandra; Gismondi, Angela; Rossi, Paolo; Santoni, Angela; Cerboni, Cristina

    2016-12-01

    NK cell cytotoxicity in Chédiak-Higashi syndrome (CHS) is strongly impaired as lytic granules are not released upon NK-target cell contact, contributing to several defects typical of this severe immunodeficiency. Correction of NK cell defects in CHS should improve the outcome of hematopoietic stem-cell transplantation, proposed as therapy. We investigated NK cell functions in a CHS patient before and after cord-blood transplantation, and the ability of in vitro IL-2 treatment to restore them. Before the transplant, the strong defect in NK cell-mediated natural and antibody-dependent cytotoxicity, as well as in IFN-γ production, could be restored up to normal levels by in vitro IL-2 treatment. This cytokine also caused the appearance of smaller lysosomal granules and their orientation towards the NK-target cell contact area, thus suggesting that IL-2 had a more general capacity to restore NK cell effector functions. Moreover after the transplant, although the successful engraftment, NK cell cytotoxicity resulted still partially impaired at one year, almost normal at ten years and, anyhow, fully recovered by in vitro IL-2 treatment. Taken together, our results indicate that IL-2 had a wide capacity to restore NK cell effector functions, being able to reverse the altered cytotoxic activity, lytic granule pattern, and cytokine production observed in the CHS patient.

  4. Activated hepatic stellate cells impair NK cell anti-fibrosis capacity through a TGF-β-dependent emperipolesis in HBV cirrhotic patients

    PubMed Central

    Shi, Jijing; Zhao, Juanjuan; Zhang, Xin; Cheng, Yongqian; Hu, Jinhua; Li, Yuanyuan; Zhao, Xin; Shang, Qinghua; Sun, Yanling; Tu, Bo; Shi, Lei; Gao, Bin; Wang, Fu-Sheng; Zhang, Zheng

    2017-01-01

    Natural killer (NK) cells can induce liver fibrosis remission by killing hepatic stellate cells (HSCs) and producing interferon (IFN)-γ in a mouse model; however, their anti-fibrotic immune-characteristics and regulatory mechanisms by HSCs remain to be determined, especially in livers from HBV-infected liver cirrhosis (LC) patients. We analyzed frequency, phenotype and anti-fibrotic function of hepatic and peripheral NK subsets in 43 HBV-LC patients. We found that hepatic NK subsets from LC patients displayed a decreased frequency, activation status and anti-fibrotic activity compared with those from chronic hepatitis B patients, which were mainly mediated by increased intrahepatic tumour-growth factor (TGF)-β because blockade of TGF-β significantly reversed NK anti-fibrotic function in vitro. In vivo, hepatic NK cells were enriched in proximity to the α-smooth muscle actin (α-SMA+) area within mild fibrosis regions; while in severe fibrotic areas, they were either directly attached to or separated from the α-SMA+ region. NK cells from LC patients could enter HSCs to form emperipolesis (a cell-in-cell structure) and become apoptotic; anti-TGF-β treatment ameliorated this emperipolesis. This finding suggested a novel mechanism by which activated HSCs impair NK cells’ anti-fibrosis capacity through a TGF-β-dependent emperipolesis in LC patients, providing an anti-fibrotic rational by enhancing NK cell activity. PMID:28291251

  5. Proteome Analysis of Distinct Developmental Stages of Human Natural Killer (NK) Cells

    PubMed Central

    Scheiter, Maxi; Lau, Ulrike; van Ham, Marco; Bulitta, Björn; Gröbe, Lothar; Garritsen, Henk; Klawonn, Frank; König, Sebastian; Jänsch, Lothar

    2013-01-01

    The recent Natural Killer (NK) cell maturation model postulates that CD34+ hematopoietic stem cells (HSC) first develop into CD56bright NK cells, then into CD56dimCD57− and finally into terminally maturated CD56dimCD57+. The molecular mechanisms of human NK cell differentiation and maturation however are incompletely characterized. Here we present a proteome analysis of distinct developmental stages of human primary NK cells, isolated from healthy human blood donors. Peptide sequencing was used to comparatively analyze CD56bright NK cells versus CD56dim NK cells and CD56dimCD57− NK cells versus CD56dimCD57+ NK cells and revealed distinct protein signatures for all of these subsets. Quantitative data for about 3400 proteins were obtained and support the current differentiation model. Furthermore, 11 donor-independently, but developmental stage specifically regulated proteins so far undescribed in NK cells were revealed, which may contribute to NK cell development and may elucidate a molecular source for NK cell effector functions. Among those proteins, S100A4 (Calvasculin) and S100A6 (Calcyclin) were selected to study their dynamic subcellular localization. Upon activation of human primary NK cells, both proteins are recruited into the immune synapse (NKIS), where they colocalize with myosin IIa. PMID:23315794

  6. The characteristics of NK cells in Schistosoma japonicum-infected mouse spleens.

    PubMed

    Li, Lu; Cha, Hefei; Yu, Xiuxue; Xie, Hongyan; Wu, Changyou; Dong, Nuo; Huang, Jun

    2015-12-01

    Natural killer (NK) cells are classic innate immune cells that play roles in many types of infectious disease. Recently, some new characteristics of NK cells were discovered. In this study, C57BL/6 mice were infected with Schistosoma japonicum for 5-6 weeks and lymphocytes were isolated from the spleen to detect some of the NK cell characteristics by multiparametric flow cytometry. The results revealed that the S. japonicum infection induced a large amount of NK cells, although the percentage of NK cells was not increased significantly. At the same time, the results showed that infected mouse splenic NK cells expressed increased levels of CD25 and CD69 and produced more IL-2, IL-4, and IL-17 and less IFN-γ after stimulation with PMA and ionomycin. This meant that NK cells played a role in S. japonicum infection. Moreover, decreased NKG2A/C/E (CD94) expression levels were detected on the surface of NK cells from infected mouse spleens, which might serve as a NK cell activation mechanism. Additionally, high levels of IL-10, but not PD-1, were expressed on the infected mouse NK cells, which implied that functional exhaustion might exist in the splenic NK cells from S. japonicum-infected mice. Collectively, our results suggest that NK cells play important roles in the course of S. japonicum infection.

  7. Expression and Functional Role of α7 Nicotinic Receptor in Human Cytokine-stimulated Natural Killer (NK) Cells.

    PubMed

    Zanetti, Samanta R; Ziblat, Andrea; Torres, Nicolás I; Zwirner, Norberto W; Bouzat, Cecilia

    2016-08-05

    The homomeric α7 nicotinic receptor (nAChR) is one of the most abundant nAChRs in the central nervous system where it contributes to cognition, attention, and working memory. α7 nAChR is also present in lymphocytes, dendritic cells (DCs), and macrophages and it is emerging as an important drug target for intervention in inflammation and sepsis. Natural killer (NK) cells display cytotoxic activity against susceptible target cells and modulate innate and adaptive immune responses through their interaction with DCs. We here show that human NK cells also express α7 nAChR. α7 nAChR mRNA is detected by RT-PCR and cell surface expression of α7 nAChR is detected by confocal microscopy and flow cytometry using α-bungarotoxin, a specific antagonist. Both mRNA and protein levels increase during NK stimulation with cytokines (IL-12, IL-18, and IL-15). Exposure of cytokine-stimulated NK cells to PNU-282987, a specific α7 nAChR agonist, increases intracellular calcium concentration ([Ca(2+)]i) mainly released from intracellular stores, indicating that α7 nAChR is functional. Moreover, its activation by PNU-282987 plus a specific positive allosteric modulator greatly enhances the Ca(2+) responses in NK cells. Stimulation of NK cells with cytokines and PNU-282987 decreases NF-κB levels and nuclear mobilization, down-regulates NKG2D receptors, and decreases NKG2D-dependent cell-mediated cytotoxicity and IFN-γ production. Also, such NK cells are less efficient to trigger DC maturation. Thus, our results demonstrate the anti-inflammatory role of α7 nAChR in NK cells and suggest that modulation of its activity in these cells may constitute a novel target for regulation of the immune response.

  8. Immunoproteasome-Deficiency Has No Effects on NK Cell Education, but Confers Lymphocytes into Targets for NK Cells in Infected Wild-Type Mice

    PubMed Central

    Bekker, Cornelis P. J.; Boog, Claire J. P.; Zaiss, Dietmar M. W.; Sijts, Alice J. A. M.

    2011-01-01

    Natural killer (NK) cells are part of the innate immune system and contribute to the eradication of virus infected cells and tumors. NK cells express inhibitory and activating receptors and their decision to kill a target cell is based on the balance of signals received through these receptors. MHC class I molecules are recognized by inhibitory receptors, and their presence during NK cell education influences the responsiveness of peripheral NK cells. We here demonstrate that mice with reduced MHC class I cell surface expression, due to deficiency of immunoproteasomes, have responsive NK cells in the periphery, indicating that the lower MHC class I levels do not alter NK cell education. Following adoptive transfer into wild-type (wt) recipients, immunoproteasome-deficient splenocytes are tolerated in naive but rejected in virus-infected recipients, in an NK cell dependent fashion. These results indicate that the relatively low MHC class I levels are sufficient to protect these cells from rejection by wt NK cells, but that this tolerance is broken in infection, inducing an NK cell-dependent rejection of immunoproteasome-deficient cells. PMID:21887316

  9. Immunoproteasome-deficiency has no effects on NK cell education, but confers lymphocytes into targets for NK cells in infected wild-type mice.

    PubMed

    van Helden, Mary J G; de Graaf, Natascha; Bekker, Cornelis P J; Boog, Claire J P; Zaiss, Dietmar M W; Sijts, Alice J A M

    2011-01-01

    Natural killer (NK) cells are part of the innate immune system and contribute to the eradication of virus infected cells and tumors. NK cells express inhibitory and activating receptors and their decision to kill a target cell is based on the balance of signals received through these receptors. MHC class I molecules are recognized by inhibitory receptors, and their presence during NK cell education influences the responsiveness of peripheral NK cells. We here demonstrate that mice with reduced MHC class I cell surface expression, due to deficiency of immunoproteasomes, have responsive NK cells in the periphery, indicating that the lower MHC class I levels do not alter NK cell education. Following adoptive transfer into wild-type (wt) recipients, immunoproteasome-deficient splenocytes are tolerated in naive but rejected in virus-infected recipients, in an NK cell dependent fashion. These results indicate that the relatively low MHC class I levels are sufficient to protect these cells from rejection by wt NK cells, but that this tolerance is broken in infection, inducing an NK cell-dependent rejection of immunoproteasome-deficient cells.

  10. CD16xCD33 bispecific killer cell engager (BiKE) activates NK cells against primary MDS and MDSC CD33+ targets.

    PubMed

    Gleason, Michelle K; Ross, Julie A; Warlick, Erica D; Lund, Troy C; Verneris, Michael R; Wiernik, Andres; Spellman, Stephen; Haagenson, Michael D; Lenvik, Alexander J; Litzow, Mark R; Epling-Burnette, Pearlie K; Blazar, Bruce R; Weiner, Louis M; Weisdorf, Daniel J; Vallera, Daniel A; Miller, Jeffrey S

    2014-05-08

    Myelodysplastic syndromes (MDS) are stem cell disorders that can progress to acute myeloid leukemia. Although hematopoietic cell transplantation can be curative, additional therapies are needed for a disease that disproportionally afflicts the elderly. We tested the ability of a CD16xCD33 BiKE to induce natural killer (NK) cell function in 67 MDS patients. Compared with age-matched normal controls, CD7(+) lymphocytes, NK cells, and CD16 expression were markedly decreased in MDS patients. Despite this, reverse antibody-dependent cell-mediated cytotoxicity assays showed potent degranulation and cytokine production when resting MDS-NK cells were triggered with an agonistic CD16 monoclonal antibody. Blood and marrow MDS-NK cells treated with bispecific killer cell engager (BiKE) significantly enhanced degranulation and tumor necrosis factor-α and interferon-γ production against HL-60 and endogenous CD33(+) MDS targets. MDS patients had a significantly increased proportion of immunosuppressive CD33(+) myeloid-derived suppressor cells (MDSCs) that negatively correlated with MDS lymphocyte populations and CD16 loss on NK cells. Treatment with the CD16xCD33 BiKE successfully reversed MDSC immunosuppression of NK cells and induced MDSC target cell lysis. Lastly, the BiKE induced optimal MDS-NK cell function irrespective of disease stage. Our data suggest that the CD16xCD33 BiKE functions against both CD33(+) MDS and MDSC targets and may be therapeutically beneficial for MDS patients.

  11. Memory-Like Antigen-Specific Human NK Cells from TB Pleural Fluids Produced IL-22 in Response to IL-15 or Mycobacterium tuberculosis Antigens.

    PubMed

    Fu, Xiaoying; Yu, Sifei; Yang, Binyan; Lao, Suihua; Li, Baiqing; Wu, Changyou

    2016-01-01

    Our previous result indicated that memory-like human natural killer (NK) cells from TB pleural fluid cells (PFCs) produced large amounts of IFN-γ in response to Bacille Calmette Guerin (BCG). Furthermore, recent studies have shown that human lymphoid tissues harbored a unique NK cell subset that specialized in production of interleukin (IL)-22, a proinflammatory cytokine that mediates host defense against pathogens. Yet little information was available with regard to the properties of IL-22 production by memory-like human NK cells. In the present study, we found that cytokines IL-15 induced and IL-12 enhanced the levels of IL-22 by NK cells from TB PFCs. In addition, IL-22 but not IL-17 was produced by NK cells from PFCs in response to BCG and M.tb-related Ags. More importantly, the subset of specific IL-22-producing NK cells were distinct from IFN-γ-producing NK cells in PFCs. CD45RO+ or CD45RO- NK cells were sorted, co-cultured with autologous monocytes and stimulated with BCG for the production of IL-22. The result demonstrated that CD45RO+ but not CD45RO- NK cells produced significantly higher level of IL-22. Anti-IL-12Rβ1 mAbs (2B10) partially inhibit the expression of IL-22 by NK cells under the culture with BCG. Consistently, BCG specific IL-22-producing NK cells from PFCs expressed CD45ROhighNKG2Dhighgranzyme Bhigh. In conclusion, our data demonstrated that memory-like antigen-specific CD45RO+ NK cells might participate in the recall immune response for M. tb infection via producing IL-22, which display a critical role to fight against M. tb.

  12. Tracking in vivo dynamics of NK cells transferred in patients undergoing stem cell transplantation.

    PubMed

    Killig, Monica; Friedrichs, Birte; Meisig, Johannes; Gentilini, Chiara; Blüthgen, Nils; Loddenkemper, Christoph; Labopin, Myriam; Basara, Nadezda; Pfrepper, Christian; Niederwieser, Dietger W; Uharek, Lutz; Romagnani, Chiara

    2014-09-01

    Haploidentical stem cell transplantation (haploSCT) offers an alternative treatment option for advanced leukemia patients lacking a HLA-compatible donor. Transfer of NK cells represents a promising therapeutic option in combination with SCT, as NK cells can promote graft versus leukemia with low risk of GVH disease. In this study, we show results from a phase I/II trial in which 24 acute myeloid leukemia patients underwent haploSCT in combination with early transfer of unmodified NK cells and observed a promising 2-year overall survival rate of 37%. By performing immunomonitoring and subsequent principal component analysis, we tracked donor NK-cell dynamics in the patients and distinguished between NK cells reconstituting from CD34(+) precursors, giving rise over time to a continuum of multiple differentiation stages, and adoptively transferred NK cells. Transferred NK cells displayed a mature phenotype and proliferated in vivo during the early days after haploSCT even in the absence of exogenous IL-2 administration. Moreover, we identified the NK-cell phenotype associated with in vivo expansion. Thus, our study indicates a promising path for adoptive transfer of unmodified NK cells in the treatment of high-risk acute myeloid leukemia.

  13. Eomeshi NK Cells in Human Liver Are Long-Lived and Do Not Recirculate but Can Be Replenished from the Circulation

    PubMed Central

    Cuff, Antonia O.; Robertson, Francis P.; Stegmann, Kerstin A.; Pallett, Laura J.; Maini, Mala K.; Davidson, Brian R.

    2016-01-01

    Human liver contains an Eomeshi population of NK cells that is not present in the blood. In this study, we show that these cells are characterized by a molecular signature that mediates their retention in the liver. By examining liver transplants where donors and recipients are HLA mismatched, we distinguish between donor liver–derived and recipient-derived leukocytes to show that Eomeslo NK cells circulate freely whereas Eomeshi NK cells are unable to leave the liver. Furthermore, Eomeshi NK cells are retained in the liver for up to 13 y. Therefore, Eomeshi NK cells are long-lived liver-resident cells. We go on to show that Eomeshi NK cells can be recruited from the circulation during adult life and that circulating Eomeslo NK cells are able to upregulate Eomes and molecules mediating liver retention under cytokine conditions similar to those in the liver. This suggests that circulating NK cells are a precursor of their liver-resident counterparts. PMID:27798170

  14. NK cells in gamma-interferon-deficient mice suppress lung innate immunity against Mycoplasma spp.

    PubMed

    Woolard, Matthew D; Hudig, Dorothy; Tabor, Leslie; Ivey, James A; Simecka, Jerry W

    2005-10-01

    The purpose of this study was to examine the 100-fold difference in mycoplasma levels in lungs of gamma interferon knockout (IFN-gamma(-/-)) mice compared to those seen with wild-type BALB/c mice at 3 days postinfection. NK cells secreted IFN-gamma; however, their cytotoxic granule extracts failed to kill mycoplasma. We found a conundrum: the clearance of organisms was as effective in NK-depleted IFN-gamma(-/-) animals as in wild-type mice (with both IFN-gamma and NK cells). NK(+) IFN-gamma(-/-) animals had high mycoplasma burdens, but, after NK-like cell depletion, mycoplasma numbers were controlled. Essentially, IFN-gamma was important in animals with NK-like cells and unimportant in animals without NK cells, suggesting that IFN-gamma counters deleterious effects of NK-like cells. Impairment of innate immunity in IFN-gamma(-/-) mice was not due to NK-like cell killing of macrophages. The increased levels of inflammatory cytokines and neutrophils in lung fluids of NK(+) IFN-gamma(-/-) mice were reduced after NK cell depletion. In summary, in the murine model that resembles chronic human disease, innate immunity to mycoplasma requires IFN-gamma when there are NK-like cells and the positive effects of IFN-gamma counteract negative effects of NK-like cells. When imbalanced, NK-like cells promote disease. Thus, it was not the lack of IFN-gamma but the presence of a previously unrecognized NK-like cell-suppressive activity that contributed to the higher mycoplasma numbers. It appears that pulmonary NK cells may contribute to the immunosuppressive environment of the lung, but when needed, these dampening effects can be counterbalanced by IFN-gamma. Furthermore, there may be instances where perturbation of this regulatory balance contributes to the susceptibility to and severity of disease.

  15. Reversal of tumor acidosis by systemic buffering reactivates NK cells to express IFN-γ and induces NK cell-dependent lymphoma control without other immunotherapies.

    PubMed

    Pötzl, Johann; Roser, David; Bankel, Lorenz; Hömberg, Nadine; Geishauser, Albert; Brenner, Christoph D; Weigand, Michael; Röcken, Martin; Mocikat, Ralph

    2017-05-01

    Like other immune cells, natural killer (NK) cells show impaired effector functions in the microenvironment of tumors, but little is known on the underlying mechanisms. Since lactate acidosis, a hallmark of malignant tissue, was shown to contribute to suppression of effective antitumor immune responses, we investigated the impact of tissue pH and lactate concentration on NK-cell functions in an aggressive model of endogenously arising B-cell lymphoma. The progressive loss of IFN-γ production by NK cells observed during development of this disease could be ascribed to decreased pH values and lactate accumulation in the microenvironment of growing tumors. Interestingly, IFN-γ expression by lymphoma-derived NK cells could be restored by transfer of these cells into a normal micromilieu. Likewise, systemic alkalization by oral delivery of bicarbonate to lymphoma-developing mice was capable of enhancing IFN-γ expression in NK cells and increasing the NK-cell numbers in the lymphoid organs where tumors were growing. By contrast, NK-cell cytotoxicity was dampened in vivo by tumor-dependent mechanisms that seemed to be different from lactate acidosis and could not be restored in a normal milieu. Most importantly, alkalization and the concomitant IFN-γ upregulation in NK cells were sufficient to significantly delay tumor growth without any other immunotherapy. This effect was strictly dependent on NK cells.

  16. Plasmid Vector-Linked Maturation of Natural Killer (NK) Cells Is Coupled to Antigen-Dependent NK Cell Activation during DNA-Based Immunization in Mice ▿

    PubMed Central

    Zhu, Ren; Mancini-Bourgine, Maryline; Zhang, Xiao Ming; Bayard, Florence; Deng, Qiang; Michel, Marie-Louise

    2011-01-01

    Plasmid DNA vaccines serve in a wide array of applications ranging from prophylactic vaccines to potential therapeutic tools against infectious diseases and cancer. In this study, we analyzed the mechanisms underlying the activation of natural killer (NK) cells and their potential role in adaptive immunity during DNA-based immunization against hepatitis B virus surface antigen in mice. We observed that the mature Mac-1+ CD27− NK cell subset increased in the liver of mice early after DNA injection, whereas the number of the less mature Mac-1+ CD27+ NK cells in the liver and spleen was significantly reduced. This effect was attributed to bacterial sequences present in the plasmid backbone rather than to the encoded antigen and was not observed in immunized MyD88-deficient mice. The activation of NK cells by plasmid-DNA injection was associated with an increase in their effector functions that depended on the expressed antigen. Maturation of NK cells was abrogated in the absence of T cells, suggesting that cross talk exists between NK cells and antigen-specific T cells. Taken together, our data unravel the mechanics of plasmid vector-induced maturation of NK cells and plasmid-encoded antigen-dependent activation of NK cells required for a crucial role of NK cells in DNA vaccine-induced immunogenicity. PMID:21775455

  17. NKT cells act through third party bone marrow-derived cells to suppress NK cell activity in the liver and exacerbate hepatic melanoma metastases.

    PubMed

    Sadegh, Leila; Chen, Peter W; Brown, Joseph R; Han, Zhiqiang; Niederkorn, Jerry Y

    2015-09-01

    Uveal melanoma (UM) is the most common intraocular tumor in adults and liver metastasis is the leading cause of death in UM patients. We have previously shown that NKT cell-deficient mice develop significantly fewer liver metastases from intraocular melanomas than do wild-type (WT) mice. Here, we examine the interplay between liver NKT cells and NK cells in resistance to liver metastases from intraocular melanomas. NKT cell-deficient CD1d(-/-) mice and WT C57BL/6 mice treated with anti-CD1d antibody developed significantly fewer liver metastases than WT mice following either intraocular or intrasplenic injection of B16LS9 melanoma cells. The increased number of metastases in WT mice was associated with reduced liver NK cytotoxicity and decreased production of IFN-γ. However, liver NK cell-mediated cytotoxic activity was identical in non-tumor bearing NKT cell-deficient mice and WT mice, indicating that liver metastases were crucial for the suppression of liver NK cells. Depressed liver NK cytotoxicity in WT mice was associated with production of IL-10 by bone marrow-derived liver cells that were neither Kupffer cells nor myeloid-derived suppressor cells and by increased IL-10 receptor expression on liver NK cells. IL-10(-/-) mice had significantly fewer liver metastases than WT mice, but were not significantly different from NKT cell-deficient mice. Thus, development of melanoma liver metastases is associated with upregulation of IL-10 in the liver and an elevated expression of IL-10 receptor on liver NK cells. This impairment of liver NK activity is NKT cell-dependent and only occurs in hosts with melanoma liver metastases.

  18. Human Cytomegalovirus Infection Enhances NK Cell Activity In Vitro

    PubMed Central

    Tschan-Plessl, Astrid; Stern, Martin; Schmied, Laurent; Retière, Christelle; Hirsch, Hans H.; Garzoni, Christian; van Delden, Christian; Boggian, Katia; Mueller, Nicolas J.; Berger, Christoph; Villard, Jean; Manuel, Oriol; Meylan, Pascal; Terszowski, Grzegorz

    2016-01-01

    Background Occurring frequently after solid organ and hematopoietic stem cell transplantation, cytomegalovirus (CMV) replication remains a relevant cause of mortality and morbidity in affected patients. Despite these adverse effects, an increased alloreactivity of natural killer (NK) cells after CMV infection has been assumed, but the underlying physiopathological mechanisms have remained elusive. Methods We used serial analyses of NK cells before and after CMV infection in kidney transplant recipients as an in vivo model for CMV primary infection to explore the imprint of CMV infection using every patient as their own control: We analyzed NK cell phenotype and function in 47 CMV seronegative recipients of CMV seropositive kidney grafts, who developed CMV primary infection posttransplant. Seronegative recipients of seronegative kidney grafts served as controls. Results We observed a significant increase of NKG2C expressing NK cells after CMV infection (mean increase, 17.5%; 95% confidence interval [95% CI], 10.2-24.9, P < 0.001), whereas cluster of differentiation (CD)57 expressing cells decreased (mean decrease, 14.1%; 95% CI, 8.0-20.2; P < 0.001). Analysis of killer immunoglobulin-like receptor (KIR) expression showed an increase of cells expressing KIR2DL1 as their only inhibitory KIR in patients carrying the cognate ligand HLA-C2 (mean increase, 10.0%; 95% CI, 1.7-18.3; P = 0.018). In C2-negative individuals, KIR2DL1 expression decreased (mean decrease, 3.9%; 95% CI, 1.6-6.2; P = 0.001). As for activating KIR, there was no conclusive change pattern. Most importantly, we observed a significantly higher NK cell degranulation and IFNγ production in response to different target cells (target K562, CD107a: mean increase, 9.9%; 95% CI, 4.8-15.0; P < 0.001; IFNγ: mean increase, 6.6%; 95% CI, 1.6-11.1; P < 0.001; target MRC-5, CD107a: mean increase, 6.9%; 95% CI, 0.7-13.1; P = 0.03; IFNγ: mean increase, 4.8%; 95% CI, 1.7-7.8; P = 0.002). Conclusions We report

  19. Immunological and Translational Aspects of NK Cell-Based Antitumor Immunotherapies

    PubMed Central

    Shevtsov, Maxim; Multhoff, Gabriele

    2016-01-01

    Natural killer (NK) cells play a pivotal role in the first line of defense against cancer. NK cells that are deficient in CD3 and a clonal T cell receptor (TCR) can be subdivided into two major subtypes, CD56dimCD16+ cytotoxic and CD56brightCD16− immunoregulatory NK cells. Cytotoxic NK cells not only directly kill tumor cells without previous stimulation by cytotoxic effector molecules, such as perforin and granzymes or via death receptor interactions, but also act as regulatory cells for the immune system by secreting cytokines and chemokines. The aim of this review is to highlight therapeutic strategies utilizing autologous and allogenic NK cells, combinations of NK cells with monoclonal antibodies to induce antibody-dependent cellular cytotoxicity, or immune checkpoint inhibitors. Additionally, we discuss the use of chimeric antigen receptor-engineered NK cells in cancer immunotherapy. PMID:27891129

  20. NK cells activated by Interleukin-4 in cooperation with Interleukin-15 exhibit distinctive characteristics

    PubMed Central

    Kiniwa, Tsuyoshi; Enomoto, Yutaka; Terazawa, Natsumi; Omi, Ai; Miyata, Naoko; Ishiwata, Kenji; Miyajima, Atsushi

    2016-01-01

    Natural killer (NK) cells are known to be activated by Th1-type cytokines, such as IL-2, -12, or -18, and they secrete a large amount of IFN-γ that accelerates Th1-type responses. However, the roles of NK cells in Th2-type responses have remained unclear. Because IL-4 acts as an initiator of Th2-type responses, we examined the characteristics of NK cells in mice overexpressing IL-4. In this study, we report that IL-4 overexpression induces distinctive characteristics of NK cells (B220high/CD11blow/IL-18Rαlow), which are different from mature conventional NK (cNK) cells (B220low/CD11bhigh/IL-18Rαhigh). IL-4 overexpression induces proliferation of tissue-resident macrophages, which contributes to NK cell proliferation via production of IL-15. These IL-4–induced NK cells (IL4-NK cells) produce higher levels of IFN-γ, IL-10, and GM-CSF, and exhibit high cytotoxicity compared with cNK cells. Furthermore, incubation of cNK cells with IL-15 and IL-4 alters their phenotype to that similar to IL4-NK cells. Finally, parasitic infection, which typically causes strong Th2-type responses, induces the development of NK cells with characteristics similar to IL4-NK cells. These IL4-NK–like cells do not develop in IL-4Rα KO mice by parasitic infection. Collectively, these results suggest a novel role of IL-4 in immune responses through the induction of the unique NK cells. PMID:27551096

  1. Wiskott-Aldrich syndrome protein is required for NK cell cytotoxicity and colocalizes with actin to NK cell-activating immunologic synapses

    NASA Astrophysics Data System (ADS)

    Orange, Jordan S.; Ramesh, Narayanaswamy; Remold-O'Donnell, Eileen; Sasahara, Yoji; Koopman, Louise; Byrne, Michael; Bonilla, Francisco A.; Rosen, Fred S.; Geha, Raif S.; Strominger, Jack L.

    2002-08-01

    The Wiskott-Aldrich syndrome (WAS) is a primary immunodeficiency disorder caused by a mutation in WAS protein (WASp) that results in defective actin polymerization. Although the function of many hematopoietic cells requires WASp, the specific expression and function of this molecule in natural killer (NK) cells is unknown. Here, we report that WAS patients have increased percentages of peripheral blood NK cells and that fresh enriched NK cells from two patients with a WASp mutation have defective cytolytic function. In normal NK cells, WASp was expressed and localized to the activating immunologic synapse (IS) with filamentous actin (F-actin). Perforin also localized to the NK cell-activating IS but at a lesser frequency than F-actin and WASp. The accumulation of F-actin and WASp at the activating IS was decreased significantly in NK cells that had been treated with the inhibitor of actin polymerization, cytochalasin D. NK cells from WAS patients lacked expression of WASp and accumulated F-actin at the activating IS infrequently. Thus, WASp has an important function in NK cells. In patients with WASp mutations, the resulting NK cell defects are likely to contribute to their disease.

  2. HMGB1 Is Involved in IFN-α Production and TRAIL Expression by HIV-1-Exposed Plasmacytoid Dendritic Cells: Impact of the Crosstalk with NK Cells.

    PubMed

    Saïdi, Héla; Bras, Marlène; Formaglio, Pauline; Melki, Marie-Thérèse; Charbit, Bruno; Herbeuval, Jean-Philippe; Gougeon, Marie-Lise

    2016-02-01

    Plasmacytoid dendritic cells (pDCs) are innate sensors of viral infections and important mediators of antiviral innate immunity through their ability to produce large amounts of IFN-α. Moreover, Toll-like receptor 7 (TLR7) and 9 (TLR9) ligands, such as HIV and CpG respectively, turn pDCs into TRAIL-expressing killer pDCs able to lyse HIV-infected CD4+ T cells. NK cells can regulate antiviral immunity by modulating pDC functions, and pDC production of IFN-α as well as cell-cell contact is required to promote NK cell functions. Impaired pDC-NK cell crosstalk was reported in the setting of HIV-1 infection, but the impact of HIV-1 on TRAIL expression and innate antiviral immunity during this crosstalk is unknown. Here, we report that low concentrations of CCR5-tropic HIV-1Ba-L promote the release of pro-inflammatory cytokines such as IFN-α, TNF-α, IFN-γ and IL-12, and CCR5-interacting chemokines (MIP-1α and MIP-1β) in NK-pDCs co-cultures. At high HIV-1BaL concentrations, the addition of NK cells did not promote the release of these mediators, suggesting that once efficiently triggered by the virus, pDCs could not integrate new activating signals delivered by NK cells. However, high HIV-1BaL concentrations were required to trigger IFN-α-mediated TRAIL expression at the surface of both pDCs and NK cells during their crosstalk. Interestingly, we identified the alarmin HMGB1, released at pDC-NK cell synapse, as an essential trigger for the secretion of IFN-α and IFN-related soluble mediators during the interplay of HIV-1 exposed pDCs with NK cells. Moreover, HMGB1 was found crucial for mTRAIL translocation to the plasma membrane of both pDCs and NK cells during their crosstalk following pDC exposure to HIV-1. Data from serum analyses of circulating HMGB1, HMGB1-specific antibodies, sTRAIL and IP-10 in a cohort of 67 HIV-1+ patients argue for the in vivo relevance of these observations. Altogether, these findings identify HMGB1 as a trigger for IFN-α-mediated

  3. Licensed and Unlicensed NK Cells: Differential Roles in Cancer and Viral Control.

    PubMed

    Tu, Megan M; Mahmoud, Ahmad Bakur; Makrigiannis, Andrew P

    2016-01-01

    Natural killer (NK) cells are known for their well characterized ability to control viral infections and eliminate tumor cells. Through their repertoire of activating and inhibitory receptors, NK cells are able to survey different potential target cells for various surface markers, such as MHC-I - which signals to the NK cell that the target is healthy - as well as stress ligands or viral proteins, which alert the NK cell to the aberrant state of the target and initiate a response. According to the "licensing" hypothesis, interactions between self-specific MHC-I receptors - Ly49 in mice and KIR in humans - and self-MHC-I molecules during NK cell development is crucial for NK cell functionality. However, there also exists a large proportion of NK cells in mice and humans, which lack self-specific MHC-I receptors and are consequentially "unlicensed." While the licensed NK cell subset plays a major role in the control of MHC-I-deficient tumors, this review will go on to highlight the important role of the unlicensed NK cell subset in the control of MHC-I-expressing tumors, as well as in viral control. Unlike the licensed NK cells, unlicensed NK cells seem to benefit from the lack of self-specific inhibitory receptors, which could otherwise be exploited by some aberrant cells for immunoevasion by upregulating the expression of ligands or mimic ligands for these receptors.

  4. Requirement and Redundancy of the Src Family Kinases Fyn and Lyn in Perforin-Dependent Killing of Cryptococcus neoformans by NK Cells

    PubMed Central

    Oykhman, Paul; Timm-McCann, Martina; Xiang, Richard F.; Islam, Anowara; Li, Shu Shun; Stack, Danuta; Huston, Shaunna M.; Ma, Ling Ling

    2013-01-01

    Natural killer (NK) cells directly recognize and kill fungi, such as the pathogenic fungus Cryptococcus neoformans, via cytolytic mechanisms. However, the precise signaling pathways governing this NK cell microbicidal activity and the implications for fungal recognition are still unknown. Previously, it was reported that NK cell anticryptococcal activity is mediated through a conserved phosphatidylinositol 3-kinase–extracellular signal-regulated kinase 1/2 (PI3K-ERK1/2) pathway. Using YT (a human NK-like cell line) and primary human NK cells, we sought to identify the upstream, receptor-proximal signaling elements that led to fungal cytolysis. We demonstrate that Src family kinases were activated in response to C. neoformans. Furthermore, pharmacologic inhibition with an Src kinase inhibitor blocked C. neoformans-induced downstream activation of PI3K and ERK1/2 and abrogated cryptococcal killing. At the same time, the inhibitor disrupted the polarization of perforin-containing granules toward the NK cell-cryptococcal synapse but had no effect on conjugate formation between the organism and the NK cell. Finally, small interfering RNA (siRNA) double (but not single) knockdown of two Src family kinases, Fyn and Lyn, blocked cryptococcal killing. Together these data demonstrate a mechanism whereby the Src family kinases, Fyn and Lyn, redundantly mediate anticryptococcal activity through the activation of PI3K and ERK1/2, which in turn facilitates killing by inducing the polarization of perforin-containing granules to the NK cell-cryptococcal synapse. PMID:23918783

  5. Natural Killers Are Made Not Born: How to Exploit NK Cells in Lung Malignancies

    PubMed Central

    Carrega, Paolo; Ferlazzo, Guido

    2017-01-01

    In recent years, progress has been made in the characterization of natural killer (NK) cells in lung malignancies, and we have now gained a better understanding of the frequency, localization, phenotype, and functional status of NK cells infiltrating these tumors. NK cell subset recruited in lung cancer is mainly capable of producing relevant cytokines rather than exerting direct cancer cell killing. Thus, the relevance of NK cells in tumor microenvironment might also go beyond the killing of tumor cells, being NK cells endowed with regulatory functions toward an ample array of immune effectors. Nevertheless, boosting their cytotoxic functions and redirecting the migration of cytotoxic NK cell subset to the tumor site might open new therapeutic avenues for lung cancer. Also, we believe that a deeper investigation into the impact of both conventional (e.g., chemotherapy) or new therapies (e.g., anti-immune checkpoints mAbs) on NK cell homeostasis in lung cancer patients is now required. PMID:28348567

  6. HLA class I downregulation is associated with enhanced NK-cell killing of melanoma cells with acquired drug resistance to BRAF inhibitors.

    PubMed

    Sottile, Rosa; Pangigadde, Pradeepa N; Tan, Thomas; Anichini, Andrea; Sabbatino, Francesco; Trecroci, Francesca; Favoino, Elvira; Orgiano, Laura; Roberts, James; Ferrone, Soldano; Kärre, Klas; Colucci, Francesco; Carbone, Ennio

    2016-02-01

    The frequent development of drug resistance to targeted therapies in cancer patients has stimulated interest in strategies counteracting resistance. Combining immunotherapies with targeted therapies is one such strategy. In this context, we asked whether human NK cells can target melanoma cells that have acquired resistance to selective inhibitors targeting activating mutants of the B-Raf kinase (BRAF inhibitors, BRAFi). We generated drug-resistant cell variants in vitro from human BRAF-mutant melanoma cell lines MEL-HO, COLO-38, SK-MEL-37, 1520 and from primary melanoma cells freshly isolated from two patients. All drug-resistant cell variants remained susceptible to lysis by IL-2-activated NK cells; and two BRAFi-resistant lines (BRAFi-R) became significantly more susceptible to NK-cell lysis than their parental lines. This was associated with significant HLA class I antigen downregulation and PD-L1 upregulation on the drug-resistant lines. Although blocking HLA class I enhanced the extent of lysis of both BRAFi-R and parental cells to NK-cell-mediated lysis, antibody-mediated inhibition of PD1-PD-L1 interactions had no detectable effect. HLA class I antigen expression on BRAFi-R melanoma variants thus appears to play a major role in their susceptibility to NK-cell cytotoxicity. These findings suggest that NK-cell-based immunotherapy may be a viable approach to treat melanoma patients with acquired resistance to BRAF inhibitors.

  7. IL-12 Enhances the Antitumor Actions of Trastuzumab via NK Cell IFN-γ Production

    PubMed Central

    Jaime-Ramirez, Alena Cristina; Mundy-Bosse, Bethany L.; Kondadasula, SriVidya; Jones, Natalie B.; Roda, Julie M.; Mani, Aruna; Parihar, Robin; Karpa, Volodymyr; Papenfuss, Tracey L.; LaPerle, Krista M.; Biller, Elizabeth; Lehman, Amy; Chaudhury, Abhik Ray; Jarjoura, David; Burry, Richard W.; Carson, William E.

    2013-01-01

    The antitumor effects of therapeutic mAbs may depend on immune effector cells that express FcRs for IgG. IL-12 is a cytokine that stimulates IFN-γ production from NK cells and T cells. We hypothesized that coadministration of IL-12 with a murine anti-HER2/neu mAb (4D5) would enhance the FcR-dependent immune mechanisms that contribute to its antitumor activity. Thrice-weekly therapy with IL-12 (1 μg) and 4D5 (1 mg/kg) significantly suppressed the growth of a murine colon adenocarcinoma that was engineered to express human HER2 (CT-26HER2/neu) in BALB/c mice compared with the result of therapy with IL-12, 4D5, or PBS alone. Combination therapy was associated with increased circulating levels of IFN-γ, monokine induced by IFN-γ, and RANTES. Experiments with IFN-γ–deficient mice demonstrated that this cytokine was necessary for the observed antitumor effects of therapy with IL-12 plus 4D5. Immune cell depletion experiments showed that NK cells (but not CD4+ or CD8+ T cells) mediated the antitumor effects of this treatment combination. Therapy of HER2/neu-positive tumors with trastuzumab plus IL-12 induced tumor necrosis but did not affect tumor proliferation, apoptosis, vascularity, or lymphocyte infiltration. In vitro experiments with CT-26HER2/neu tumor cells revealed that IFN-γ induced an intracellular signal but did not inhibit cellular proliferation or induce apoptosis. Taken together, these data suggest that tumor regression in response to trastuzumab plus IL-12 is mediated through NK cell IFN-γ production and provide a rationale for the coadministration of NK cell-activating cytokines with therapeutic mAbs. PMID:21321106

  8. Purification of human NK cell developmental intermediates from lymph nodes and tonsils.

    PubMed

    Freud, Aharon G; Caligiuri, Michael A

    2010-01-01

    Accumulating data indicate that human natural killer (NK) cells undergo terminal maturation in secondary lymphoid tissues (SLTs) including lymph nodes (LNs) and tonsils. In addition, recent studies have revealed that maturing NK cells progress through at least five functionally discrete stages of development within SLTs. These discoveries provide unique possibilities for researchers to investigate the natural processes governing human NK cell development, as they exist in vivo, through analysis of NK cell maturational intermediates found in situ. Herein we describe a detailed, yet simple, four-step protocol for the viable enrichment and purification of human NK cell developmental intermediates from LNs and tonsils.

  9. NK Cells Alleviate Lung Inflammation by Negatively Regulating Group 2 Innate Lymphoid Cells.

    PubMed

    Bi, Jiacheng; Cui, Lulu; Yu, Guang; Yang, Xiaolu; Chen, Youhai; Wan, Xiaochun

    2017-03-08

    Group 2 innate lymphoid cells (ILC2s) play an important role in orchestrating type II immune responses. However, the cellular mechanisms of group 2 innate lymphoid cell regulation remain poorly understood. In this study, we found that activated NK cells inhibited the proliferation of, as well as IL-5 and IL-13 production by, ILC2s in vitro via IFN-γ. In addition, in a murine model of ILC2 expansion in the liver, polyinosinic-polycytidylic acid, an NK cell-activating agent, inhibited ILC2 proliferation, IL-5 and IL-13 production, and eosinophil recruitment. Such effects of polyinosinic-polycytidylic acid were abrogated in NK cell-depleted mice and in IFN-γ-deficient mice. Adoptively transferring wild-type NK cells into NK cell-depleted mice resulted in fewer ILC2s induced by IL-33 compared with the transfer of IFN-γ-deficient NK cells. Importantly, during the early stage of papain- or bleomycin-induced lung inflammation, depletion of NK cells resulted in increased ILC2 numbers and enhanced cytokine production by ILC2s, as well as aggravated eosinophilia and goblet cell hyperplasia. Collectively, these data show that NK cells negatively regulate ILC2s during the early stage of lung inflammation, which represents the novel cellular interaction between two family members of ILCs.

  10. Activation of NK cells and disruption of PD-L1/PD-1 axis: two different ways for lenalidomide to block myeloma progression.

    PubMed

    Giuliani, Massimo; Janji, Bassam; Berchem, Guy

    2017-02-09

    Natural Killer (NK) cells play a critical role against tumor cells in hematological malignancies. Their activating receptors are essential in tumor cell killing. In Multiple Myeloma (MM) patients, NK cell differentiation, activation and cytotoxic potential are strongly impaired leading to MM escape from immune surveillance in tissues and bone marrow. Mechanisms used by MM to affect NK cell functions are mediated by the release of soluble factors, the expression of activating and inhibitory NK cell ligands, and the expression of immune check-point inhibitors. Lenalidomide represents an efficient clinical approach in MM treatment to improve patients' survival. Lenalidomide does not only promotes tumor apoptosis, but also stimulates T and NK cells, thereby facilitating NK-mediated tumor recognition and killing. This occurs since Lenalidomide acts on several critical points: stimulates T cell proliferation and cytokine secretion; decreases the expression of the immune check-point inhibitor Programmed Death-1 (PD-1) on both T and NK cells in MM patients; decreases the expression of both PD-1 and PD-L1 on MM cells; promotes MM cell death and abrogates MM/stromal microenvironment cross-talk, a process known to promote the MM cell survival and proliferation. This leads to the inhibition of the negative signal induced by PD-1/PD-L1 axis on NK cells, restoring NK cell cytotoxic functions. Given the importance of an effective immune response to counteract the MM progression and the promising approaches using anti-PD-1/PD-L1 strategies, we will discuss in this review how Lenalidomide could represent an adequate approach to re-establish the recognition against MM by exhausted NK cell.

  11. The Correlation between NK Cell and Liver Function in Patients with Primary Hepatocellular Carcinoma

    PubMed Central

    Zeng, Xiao-Hui; Min, Lu

    2014-01-01

    Background/Aims This study aimed to detect the expression of natural killer (NK) cell receptor natural killer group 2D (NKG2D) in the peripheral blood of patients with primary hepatocellular carcinoma and to discuss the correlation between NK cell cytotoxicity and liver function. Methods The number of NK cells and the expression of NK cell receptor NKG2D in peripheral blood were determined by flow cytometry in patients with primary hepatocellular carcinoma, hepatitis B cirrhosis, chronic hepatitis B, and healthy controls. Results When compared with patients in the healthy and the chronic hepatitis B groups, the primary hepatocellular carcinoma group showed significant decreases in all parameters, including the cytotoxicity of NK cells on K562 cells, expression rate of NKG2D in NK cells, number of NKG2D+ NK cells, expression level of NKG2D, and number of NK cells (p<0.05). The activity of NK cells showed a positive correlation, whereas the Child-Pugh scores in the primary hepatocellular carcinoma and the hepatitis B cirrhosis groups showed a negative correlation with all parameters detected above. Conclusions The decrease of NK cell activity in patients with primary hepatocellular carcinoma is closely related to their lower expression of NKG2D. Liver function affects the expression of NKG2D and the activity of NK cells. PMID:24827627

  12. Biallelic mutations in IRF8 impair human NK cell maturation and function

    PubMed Central

    Mace, Emily M.; Gunesch, Justin T.; Chinn, Ivan K.; Angelo, Laura S.; Maisuria, Sheetal; Keller, Michael D.; Togi, Sumihito; Watkin, Levi B.; LaRosa, David F.; Jhangiani, Shalini N.; Muzny, Donna M.; Stray-Pedersen, Asbjørg; Coban Akdemir, Zeynep; Smith, Jansen B.; Hernández-Sanabria, Mayra; Le, Duy T.; Hogg, Graham D.; Cao, Tram N.; Freud, Aharon G.; Szymanski, Eva P.; Collin, Matthew; Cant, Andrew J.; Gibbs, Richard A.; Holland, Steven M.; Caligiuri, Michael A.; Ozato, Keiko; Paust, Silke; Doody, Gina M.; Lupski, James R.; Orange, Jordan S.

    2016-01-01

    Human NK cell deficiencies are rare yet result in severe and often fatal disease, particularly as a result of viral susceptibility. NK cells develop from hematopoietic stem cells, and few monogenic errors that specifically interrupt NK cell development have been reported. Here we have described biallelic mutations in IRF8, which encodes an interferon regulatory factor, as a cause of familial NK cell deficiency that results in fatal and severe viral disease. Compound heterozygous or homozygous mutations in IRF8 in 3 unrelated families resulted in a paucity of mature CD56dim NK cells and an increase in the frequency of the immature CD56bright NK cells, and this impairment in terminal maturation was also observed in Irf8–/–, but not Irf8+/–, mice. We then determined that impaired maturation was NK cell intrinsic, and gene expression analysis of human NK cell developmental subsets showed that multiple genes were dysregulated by IRF8 mutation. The phenotype was accompanied by deficient NK cell function and was stable over time. Together, these data indicate that human NK cells require IRF8 for development and functional maturation and that dysregulation of this function results in severe human disease, thereby emphasizing a critical role for NK cells in human antiviral defense. PMID:27893462

  13. NK cells modulate the inflammatory response to corneal epithelial abrasion and thereby support wound healing.

    PubMed

    Liu, Qiong; Smith, C Wayne; Zhang, Wanyu; Burns, Alan R; Li, Zhijie

    2012-08-01

    Natural killer (NK) cells are lymphocytes of the innate immune system that have crucial cytotoxic and regulatory roles in adaptive immunity and inflammation. Herein, we consider a role for these cells in corneal wound healing. After a 2-mm central epithelial abrasion of the mouse cornea, a subset of classic NK cells migrated into the limbus and corneal stroma, peaking at 24 hours with an eightfold increase over baseline. Depletion of γδ T cells significantly reduced NK cell accumulation (>70%; P < 0.01); however, in neutrophil-depleted animals, NK cell influx was normal. Isolated spleen NK cells migrated to the wounded cornea, and this migration was reduced by greater than 60% (P < 0.01) by ex vivo antibody blocking of NK cell CXCR3 or CCR2. Antibody-induced depletion of NK cells significantly altered the inflammatory reaction to corneal wounding, as evidenced by a 114% increase (P < 0.01) in neutrophil influx at a time when acute inflammation is normally waning. Functional blocking of NKG2D, an activating receptor for NK cell cytotoxicity and cytokine secretion, did not inhibit NK cell immigration, but significantly increased neutrophil influx. Consistent with excessive neutrophil accumulation, NK depletion and blocking of NKG2D also inhibited corneal nerve regeneration and epithelial healing (P < 0.01). Findings of this study suggest that NK cells are actively involved in corneal healing by limiting the innate acute inflammatory reaction to corneal wounding.

  14. Biallelic mutations in IRF8 impair human NK cell maturation and function.

    PubMed

    Mace, Emily M; Bigley, Venetia; Gunesch, Justin T; Chinn, Ivan K; Angelo, Laura S; Care, Matthew A; Maisuria, Sheetal; Keller, Michael D; Togi, Sumihito; Watkin, Levi B; LaRosa, David F; Jhangiani, Shalini N; Muzny, Donna M; Stray-Pedersen, Asbjørg; Coban Akdemir, Zeynep; Smith, Jansen B; Hernández-Sanabria, Mayra; Le, Duy T; Hogg, Graham D; Cao, Tram N; Freud, Aharon G; Szymanski, Eva P; Savic, Sinisa; Collin, Matthew; Cant, Andrew J; Gibbs, Richard A; Holland, Steven M; Caligiuri, Michael A; Ozato, Keiko; Paust, Silke; Doody, Gina M; Lupski, James R; Orange, Jordan S

    2017-01-03

    Human NK cell deficiencies are rare yet result in severe and often fatal disease, particularly as a result of viral susceptibility. NK cells develop from hematopoietic stem cells, and few monogenic errors that specifically interrupt NK cell development have been reported. Here we have described biallelic mutations in IRF8, which encodes an interferon regulatory factor, as a cause of familial NK cell deficiency that results in fatal and severe viral disease. Compound heterozygous or homozygous mutations in IRF8 in 3 unrelated families resulted in a paucity of mature CD56dim NK cells and an increase in the frequency of the immature CD56bright NK cells, and this impairment in terminal maturation was also observed in Irf8-/-, but not Irf8+/-, mice. We then determined that impaired maturation was NK cell intrinsic, and gene expression analysis of human NK cell developmental subsets showed that multiple genes were dysregulated by IRF8 mutation. The phenotype was accompanied by deficient NK cell function and was stable over time. Together, these data indicate that human NK cells require IRF8 for development and functional maturation and that dysregulation of this function results in severe human disease, thereby emphasizing a critical role for NK cells in human antiviral defense.

  15. NK cell trafficking in health and autoimmunity:a comprehensive review.

    PubMed

    Peng, Hui; Tian, Zhigang

    2014-10-01

    Natural killer (NK) cells represent an important subpopulation of lymphocytes that are distributed throughout the body. The development of NK cells primarily occurs in the bone marrow during adult life, involving several putative intermediate stages that finally result in functional maturation. At steady state, NK cell egress from the bone marrow to various peripheral areas is controlled by a network of adhesion molecules, including integrins, selectins, and chemokine receptors and their corresponding ligands. NK cells at different developmental stages express distinct repertoire of adhesion molecules and can therefore be recruited to different sites of the body, including lymphoid and non-lymphoid tissues, and NK cells undergo further differentiation driven by local microenvironmental signals, resulting in unique tissue-specific NK cells. Through their abilities of cytotoxicity and cytokine production, NK cells not only play key roles in the innate immune system, but also participate in shaping adaptive immune responses. On the basis of their heterogeneity in phenotype, function, and tissue distribution, NK cells can be further subdivided into distinct subsets. Under pathological conditions, such as in autoimmune, inflammatory, and infectious diseases, as local microenvironment changes, NK cell subsets would redistribute between tissues and organs and rapidly accumulate at the local pathological sites to exert their effector functions. Here, we describe the development and tissue distribution of NK cell subsets in mice and humans. We focus on the trafficking of NK cell subsets within the bone marrow and emigration into periphery at steady state, and molecular mechanisms involved in their trafficking in autoimmune diseases.

  16. Voluntary Running Suppresses Tumor Growth through Epinephrine- and IL-6-Dependent NK Cell Mobilization and Redistribution.

    PubMed

    Pedersen, Line; Idorn, Manja; Olofsson, Gitte H; Lauenborg, Britt; Nookaew, Intawat; Hansen, Rasmus Hvass; Johannesen, Helle Hjorth; Becker, Jürgen C; Pedersen, Katrine S; Dethlefsen, Christine; Nielsen, Jens; Gehl, Julie; Pedersen, Bente K; Thor Straten, Per; Hojman, Pernille

    2016-03-08

    Regular exercise reduces the risk of cancer and disease recurrence. Yet the mechanisms behind this protection remain to be elucidated. In this study, tumor-bearing mice randomized to voluntary wheel running showed over 60% reduction in tumor incidence and growth across five different tumor models. Microarray analysis revealed training-induced upregulation of pathways associated with immune function. NK cell infiltration was significantly increased in tumors from running mice, whereas depletion of NK cells enhanced tumor growth and blunted the beneficial effects of exercise. Mechanistic analyses showed that NK cells were mobilized by epinephrine, and blockade of β-adrenergic signaling blunted training-dependent tumor inhibition. Moreover, epinephrine induced a selective mobilization of IL-6-sensitive NK cells, and IL-6-blocking antibodies blunted training-induced tumor suppression, intratumoral NK cell infiltration, and NK cell activation. Together, these results link exercise, epinephrine, and IL-6 to NK cell mobilization and redistribution, and ultimately to control of tumor growth.

  17. Low baseline levels of NK cells may predict a positive response to ipilimumab in melanoma therapy.

    PubMed

    Tietze, Julia K; Angelova, Daniela; Heppt, Markus V; Ruzicka, Thomas; Berking, Carola

    2016-11-28

    The introduction of immune checkpoint blockade (ICB) has been a breakthrough in the therapy of metastatic melanoma. The influence of ICB on T-cell populations has been studied extensively, but little is known about the effect on NK cells. In this study, we analysed the relative and absolute amounts of NK cells and of the subpopulations of CD56(dim) and CD56(bright) NK cells among the peripheral blood mononuclear cells (PBMCs) of 32 patients with metastatic melanoma before and under treatment with ipilimumab or pembrolizumab by flow cytometry. In 15 (47%) patients, an abnormal low amount of NK cells was found at baseline. Analysis of the subpopulations showed also low or normal baseline levels for CD56(dim) NK cells, whereas the baseline levels of CD56(bright) NK cells were either normal or abnormally high. The relative and absolute amounts of NK cells and of CD56(dim) and CD56(bright) NK cell subpopulations in patients with a normal baseline did not change under treatment. However, patients with a low baseline of NK cells and CD56(dim) NK cells showed a significant increase in these immune cell subsets, but the amounts remained to be lower than the normal baseline. The amount of CD56(bright) NK cells was unaffected by treatment. The baseline levels of NK cells were correlated with the number of metastatic organs. Their proportion increased, whereas the expression of NKG2D decreased significantly when more than one organ was affected by metastases. Low baseline levels of NK cells and CD56(dim) NK cells as well as normal baseline levels of CD56(bright) NK cells correlated significantly with a positive response to ipilimumab but not to pembrolizumab. Survival curves of patients with low amounts of CD56(dim) NK cells treated with ipilimumab showed a trend to longer survival. Normal baseline levels of CD56(bright) NK cells were significantly correlated with longer survival as compared to patients with high baseline levels. In conclusion, analysis of the amounts of total

  18. Helper role of NK cells during the induction of anticancer responses by dendritic cells.

    PubMed

    Kalinski, Pawel; Giermasz, Adam; Nakamura, Yutaro; Basse, Per; Storkus, Walter J; Kirkwood, John M; Mailliard, Robbie B

    2005-02-01

    Recent reports demonstrate that natural killer (NK) cells and dendritic cells (DC) support each other's activity in a positive feedback. We observed that activated NK cells induce the maturation of DCs into stable type-1 polarized DCs (DC1), characterized by up to 100-fold enhanced ability to produce IL-12p70 in response to subsequent interaction with Th cells. DC1 induction depends on NK cell-produced IFN-gamma and TNF-alpha, with a possible involvement of additional factors. DC1, induced by NK cells or by NK cell-related soluble factors, are stable, resistant to tumor-related suppressive factors, and show strongly enhanced ability to induce Th1 and CTL responses. In analogy to resting T cells, the induction of "helper" function of NK cells relies on a two-signal activation paradigm. While NKG2D-dependent tumor cell recognition is sufficient to induce the cytotoxic "effector" function of NK cells, the induction of "NK cell help" requires additional signals from type-1 IFNs, products of virally-infected cells, or from IL-2. Compared to non-polarized DCs currently-used in clinical trials, DC1s act as superior inducers of anti-cancer CTL responses during in vitro sensitization. The current data provides rationale for the clinical use of DC1s in cancer and chronic infections (such as HIV), as a new generation DC-based vaccines, uniquely combining fully mature DC status with an elevated, rather than "exhausted" ability to produce bioactive IL-12p70. We are currently implementing stage I/II clinical trials, testing the effectiveness of DC1s induced by NK cells or by NK cell-related factors, as therapeutic vaccines against melanoma.

  19. Bone marrow-derived mesenchymal stem cells suppress NK cell recruitment and activation in PolyI:C-induced liver injury.

    PubMed

    Qu, Mengmeng; Cui, Jun; Zhu, Jun; Ma, Yuhong; Yuan, Xu; Shi, Jinming; Guo, Deyin; Li, Changyong

    2015-10-16

    Mesenchymal stem cells (MSCs) have been shown to have an immunomodulatory capability and clinical potential in immune diseases. However, it is unknown how MSCs may affect immunity in liver injury. This study was designed to explore the effect of bone marrow-derived MSCs (BM-MSCs) on hepatic natural killer (NK) cells in polyinosinic-polycytidylic acid (PolyI:C)-induced liver injury. Unlike in controls, adoptive transfer of BM-MSCs in mice ameliorated PolyI:C-induced liver injury, as shown by lower alanine aminotransferase levels and decreased lymphocyte infiltration in the liver. Importantly, BM-MSCs suppress NK cell accumulation and activation in the liver, which plays an important role in PolyI:C-induced liver injury. Furthermore, NK cells co-cultured with BM-MSCs reduced expression of sphingosine-1-phosphate receptor type 5 (S1PR5), an important receptor required for NK cell trafficking in vivo. BM-MSC administration suppressed the elevation of expression of S1PR5 in the liver induced by PolyI:C injection. Accordingly, BM-MSCs inhibited the chemotactic activity of NK cells induced by sphingosine-1-phosphate (S1P, the ligand of S1PR5). Our results provide an additional mechanism for the immunosuppressive effect of BM-MSCs on NK cells, which further supports the therapeutic potential of BM-MSCs in immune-mediated disorders, including those in which NK cells play a major role.

  20. Higher Frequency of NK and CD4+ T-Cells in Mucosa and Potent Cytotoxic Response in HIV Controllers

    PubMed Central

    Taborda, Natalia Andrea; González, Sandra Milena; Alvarez, Cristiam Mauricio; Correa, Luis Alfonso; Montoya, Carlos Julio; Rugeles, María Teresa

    2015-01-01

    HIV infection induces immune alterations, mainly in gut mucosa, where the main target cells reside. However, the evolution of the infection is variable among infected individuals, as evidenced by HIV controllers who exhibit low or undetectable viral load in the absence of treatment. The aim of this study was to evaluate the frequency, phenotype and activity of T and NK cells in peripheral blood and gut mucosa in a cohort of Colombian HIV controllers. Blood and gut biopsies were included. The frequency and the activation status of T and NK cells were performed by flow cytometry. In addition, Gag-stimulated CD8+ T-cells and cytokine-stimulated NK cells were tested for cytotoxic activity. Finally, microbial translocation was measured by plasma lipopolysaccharide quantification. Compared with HIV-progressors, HIV controllers exhibited higher frequency of CD4+ T and NK cells, and lower expression of activation molecules in blood and mucosal immune cells, as well as lower microbial translocation. An increased production of molecules associated with cytotoxic activity of CD8+ T-cells in blood and mucosa and a higher percentage of polyfunctional CD8+ T cells in blood were also observed in HIV controllers. In addition, an increased activity of NK cells was observed in blood. These findings suggest that HIV controllers have a potent immune response, mainly mediated by cytotoxic cells that control HIV replication, which contribute to reducing alterations at the gut mucosa. PMID:26291824

  1. Tonsillar CD56brightNKG2A+ NK cells restrict primary Epstein-Barr virus infection in B cells via IFN-γ

    PubMed Central

    Jud, Aurelia; Kotur, Monika; Berger, Christoph; Gysin, Claudine

    2017-01-01

    Natural killer (NK) cells constitute the first line of defense against viruses and cancers cells. Epstein–Barr virus (EBV) was the first human virus to be directly implicated in carcinogenesis, and EBV infection is associated with a broad spectrum of B cell lymphomas. How NK cells restrict EBV-associated oncogenesis is not understood. Here, we investigated the efficacies and mechanisms of distinct NK cell subsets from tonsils, the portal of entry of EBV, in limiting EBV infection in naïve, germinal center-associated and memory B cells. We found that CD56bright and NKG2A expression sufficiently characterizes the potent anti-EBV capacity of tonsillar NK cells. We observed restriction of EBV infection in B cells as early as 18 hours after infection. The restriction was most efficient in naïve B cells and germinal center-associated B cells, the B cell subsets that exhibited highest susceptibility to EBV infection in vitro. IFN-γ release by and partially NKp44 engagement of CD56bright and NKG2A positive NK cells mediated the restriction that eventually inhibited B-cell transformation. Thus, harnessing CD56brightNKG2A+ NK cell function might be promising to improve treatment strategies that target EBV-associated B cell lymphomas. PMID:28008151

  2. The Past, Present, and Future of NK Cells in Hematopoietic Cell Transplantation and Adoptive Transfer.

    PubMed

    Cichocki, Frank; Verneris, Michael R; Cooley, Sarah; Bachanova, Veronika; Brunstein, Claudio G; Blazar, Bruce R; Wagner, John; Schlums, Heinrich; Bryceson, Yenan T; Weisdorf, Daniel J; Miller, Jeffrey S

    2016-01-01

    Hematopoietic cell transplantation (HCT) has been used as a part of cancer therapy for over half a decade. Beyond the necessity for donor-derived cells to reconstitute hematopoiesis after radiation and chemotherapy, immunologic reconstitution from allogeneic cells is important for the elimination of residual tumor cells. Natural killer (NK) cells are first among lymphocytes to reconstitute post-transplant and protect against cancer relapse. In this review, we provide a historical perspective on the role of NK cells in cancer control in the transplant setting and focus on current research aimed at improving NK cell responses for therapeutic benefit.

  3. Role of NK, NKT cells and macrophages in liver transplantation

    PubMed Central

    Fahrner, René; Dondorf, Felix; Ardelt, Michael; Settmacher, Utz; Rauchfuss, Falk

    2016-01-01

    Liver transplantation has become the treatment of choice for acute or chronic liver disease. Because the liver acts as an innate immunity-dominant organ, there are immunological differences between the liver and other organs. The specific features of hepatic natural killer (NK), NKT and Kupffer cells and their role in the mechanism of liver transplant rejection, tolerance and hepatic ischemia-reperfusion injury are discussed in this review. PMID:27468206

  4. Nitric oxide is a mediator of tachykinin NK3 receptor-induced relaxation in rat mesenteric artery.

    PubMed Central

    Mizuta, A.; Takano, Y.; Honda, K.; Saito, R.; Matsumoto, T.; Kamiya, H.

    1995-01-01

    1. The mechanism of vasodilatation induced by tachykinin peptides was studied in isolated mesenteric arteries of rats. 2. Senktide, a selective NK3 agonist, elicited potent endothelium-dependent relaxation of arteries precontracted with phenylephrine (10(-5) M), but an NK1 agonist did not. 3. A non-peptide NK3 antagonist, SR 142801, inhibited senktide-induced relaxation. However, a non-peptide NK1 antagonist, CP-96,345, and a peptide-based NK2 antagonist, L-659,877, had no effect on senktide-induced relaxation. 4. N omega-nitro-L-arginine (L-NOARG), a nitric oxide synthesis inhibitor, markedly attenuated the relaxant response to senktide. 5. These results suggest that the endothelium of rat mesenteric arteries possesses tachykinin NK3 receptors, and that NK3 agonist-induced vasodilatation is mediated by release of nitric oxide (NO) from the endothelium. PMID:8680725

  5. Hepatitis C Virus-Induced Myeloid-Derived Suppressor Cells Suppress NK Cell IFN-γ Production by Altering Cellular Metabolism via Arginase-1.

    PubMed

    Goh, Celeste C; Roggerson, Krystal M; Lee, Hai-Chon; Golden-Mason, Lucy; Rosen, Hugo R; Hahn, Young S

    2016-03-01

    The hepatitis C virus (HCV) infects ∼ 200 million people worldwide. The majority of infected individuals develop persistent infection, resulting in chronic inflammation and liver disease, including cirrhosis and hepatocellular carcinoma. The ability of HCV to establish persistent infection is partly due to its ability to evade the immune response through multiple mechanisms, including suppression of NK cells. NK cells control HCV replication during the early phase of infection and regulate the progression to chronic disease. In particular, IFN-γ produced by NK cells limits viral replication in hepatocytes and is important for the initiation of adaptive immune responses. However, NK cell function is significantly impaired in chronic HCV patients. The cellular and molecular mechanisms responsible for impaired NK cell function in HCV infection are not well defined. In this study, we analyzed the interaction of human NK cells with CD33(+) PBMCs that were exposed to HCV. We found that NK cells cocultured with HCV-conditioned CD33(+) PBMCs produced lower amounts of IFN-γ, with no effect on granzyme B production or cell viability. Importantly, this suppression of NK cell-derived IFN-γ production was mediated by CD33(+)CD11b(lo)HLA-DR(lo) myeloid-derived suppressor cells (MDSCs) via an arginase-1-dependent inhibition of mammalian target of rapamycin activation. Suppression of IFN-γ production was reversed by l-arginine supplementation, consistent with increased MDSC arginase-1 activity. These novel results identify the induction of MDSCs in HCV infection as a potent immune evasion strategy that suppresses antiviral NK cell responses, further indicating that blockade of MDSCs may be a potential therapeutic approach to ameliorate chronic viral infections in the liver.

  6. EAT-2, a SAP-like adaptor, controls NK cell activation through phospholipase Cγ, Ca++, and Erk, leading to granule polarization.

    PubMed

    Pérez-Quintero, Luis-Alberto; Roncagalli, Romain; Guo, Huaijian; Latour, Sylvain; Davidson, Dominique; Veillette, André

    2014-04-07

    Ewing's sarcoma-associated transcript 2 (EAT-2) is an Src homology 2 domain-containing intracellular adaptor related to signaling lymphocytic activation molecule (SLAM)-associated protein (SAP), the X-linked lymphoproliferative gene product. Both EAT-2 and SAP are expressed in natural killer (NK) cells, and their combined expression is essential for NK cells to kill abnormal hematopoietic cells. SAP mediates this function by coupling SLAM family receptors to the protein tyrosine kinase Fyn and the exchange factor Vav, thereby promoting conjugate formation between NK cells and target cells. We used a variety of genetic, biochemical, and imaging approaches to define the molecular and cellular mechanisms by which EAT-2 controls NK cell activation. We found that EAT-2 mediates its effects in NK cells by linking SLAM family receptors to phospholipase Cγ, calcium fluxes, and Erk kinase. These signals are triggered by one or two tyrosines located in the carboxyl-terminal tail of EAT-2 but not found in SAP. Unlike SAP, EAT-2 does not enhance conjugate formation. Rather, it accelerates polarization and exocytosis of cytotoxic granules toward hematopoietic target cells. Hence, EAT-2 promotes NK cell activation by molecular and cellular mechanisms distinct from those of SAP. These findings explain the cooperative and essential function of these two adaptors in NK cell activation.

  7. Transcription factor KLF2 regulates homeostatic NK cell proliferation and survival.

    PubMed

    Rabacal, Whitney; Pabbisetty, Sudheer K; Hoek, Kristen L; Cendron, Delphine; Guo, Yin; Maseda, Damian; Sebzda, Eric

    2016-05-10

    Natural killer (NK) cells are innate lymphocytes that recognize and lyse virally infected or transformed cells. This latter property is being pursued in clinics to treat leukemia with the hope that further breakthroughs in NK cell biology can extend treatments to other cancers. At issue is the ability to expand transferred NK cells and prolong their functionality within the context of a tumor. In terms of NK cell expansion and survival, we now report that Kruppel-like factor 2 (KLF2) is a key transcription factor that underpins both of these events. Excision of Klf2 using gene-targeted mouse models promotes spontaneous proliferation of immature NK cells in peripheral tissues, a phenotype that is replicated under ex vivo conditions. Moreover, KLF2 imprints a homeostatic migration pattern on mature NK cells that allows these cells to access IL-15-rich microenvironments. KLF2 accomplishes this feat within the mature NK cell lineage via regulation of a subset of homing receptors that respond to homeostatic ligands while leaving constitutively expressed receptors that recognize inflammatory cytokines unperturbed. Under steady-state conditions, KLF2-deficient NK cells alter their expression of homeostatic homing receptors and subsequently undergo apoptosis due to IL-15 starvation. This novel mechanism has implications regarding NK cell contraction following the termination of immune responses including the possibility that retention of an IL-15 transpresenting support system is key to extending NK cell activity in a tumor environment.

  8. Decreased NK-cell tumour immunosurveillance consequent to JAK inhibition enhances metastasis in breast cancer models

    PubMed Central

    Bottos, Alessia; Gotthardt, Dagmar; Gill, Jason W.; Gattelli, Albana; Frei, Anna; Tzankov, Alexandar; Sexl, Veronika; Wodnar-Filipowicz, Aleksandra; Hynes, Nancy E.

    2016-01-01

    The JAK/STAT pathway is an attractive target for breast cancer therapy due to its frequent activation, and clinical trials evaluating JAK inhibitors (JAKi) in advanced breast cancer are ongoing. Using patient biopsies and preclinical models of breast cancer, we demonstrate that the JAK/STAT pathway is active in metastasis. Unexpectedly, blocking the pathway with JAKi enhances the metastatic burden in experimental and orthotopic models of breast cancer metastasis. We demonstrate that this prometastatic effect is due to the immunosuppressive activity of JAKi with ensuing impairment of NK-cell-mediated anti-tumour immunity. Furthermore, we show that immunostimulation with IL-15 overcomes the enhancing effect of JAKi on metastasis formation. Our findings highlight the importance of evaluating the effect of targeted therapy on the tumour environment. The impact of JAKi on NK cells and the potential value of immunostimulators to overcome the weakened tumour immunosurveillance, are worthwhile considering in the clinical setting of breast cancer. PMID:27406745

  9. The Human Cytomegalovirus MHC Class I Homolog UL18 Inhibits LIR-1+ but Activates LIR-1− NK Cells1

    PubMed Central

    Prod’homme, Virginie; Griffin, Cora; Aicheler, Rebecca J.; Wang, Eddie C. Y.; McSharry, Brian P.; Rickards, Carole R.; Stanton, Richard J.; Borysiewicz, Leszek K.; López-Botet, Miguel; Wilkinson, Gavin W. G.; Tomasec, Peter

    2010-01-01

    The inhibitory leukocyte Ig-like receptor 1 (LIR-1, also known as ILT2, CD85j, or LILRB1) was identified by its high affinity for the human CMV (HCMV) MHC class I homolog gpUL18. The role of this LIR-1-gpUL18 interaction in modulating NK recognition during HCMV infection has previously not been clearly defined. In this study, LIR-1+ NKL cell-mediated cytotoxicity was shown to be inhibited by transduction of targets with a replication-deficient adenovirus vector encoding UL18 (RAd-UL18). Fibroblasts infected with an HCMV UL18 mutant (ΔUL18) also exhibited enhanced susceptibility to NKL killing relative to cells infected with the parental virus. In additional cytolysis assays, UL18-mediated protection was also evident in the context of adenovirus vector transduction and HCMV infection of autologous fibroblast targets using IFN-α-activated NK bulk cultures derived from a donor with a high frequency of LIR-1+ NK cells. A single LIR-1high NK clone derived from this donor was inhibited by UL18, while 3 of 24 clones were activated. CD107 mobilization assays revealed that LIR-1+ NK cells were consistently inhibited by UL18 in all tested donors, but this effect was often masked in the global response by UL18-mediated activation of a subset of LIR-1− NK cells. Although Ab-blocking experiments support UL18 inhibition being induced by a direct interaction with LIR-1, the UL18-mediated activation is LIR-1 independent. PMID:17372005

  10. Genetic deletion of Cxcl14 in mice alters uterine NK cells

    SciTech Connect

    Cao, Qichen; Chen, Hua; Deng, Zhili; Yue, Jingwen; Chen, Qi; Cao, Yujing; Ning, Lina; Lei, Xiaohua; Duan, Enkui

    2013-06-14

    Highlights: •We first examined the expression of Cxcl14 in MLAp and DB of uterus. •We found the uNK cells in MLAp and decidua express Cxcl14. •In Cxcl14{sup −/−} placenta, we found significantly decreased uNK cells. •We first performed microarray to compare the gene expression in MLAp and DB. -- Abstract: The uterine natural killer cells (uNK cells) are the major immune cells in pregnant uterus and the number of uNK cells is dramatically increased during placentation and embryo development. The uNK cells are necessary for the immune tolerance, cytokine secretion and angiogenesis of placenta. Former studies indicated that the population expansion of uNK cells was accomplished through recruitment of NK cell precursors from the spleen and bone marrow, but not proliferation of NK cells. However, the necessary molecules within this process were little understood. Here in our study, we found the co-localized expression of Cxcl14 protein with uNK cells in E13.5 pregnant uterus. Moreover, we used Cxcl14 knockout mice to examine uNK cells in mesometrial lymphoid aggregate of pregnancy (MLAp) and decidua basalis (DB) of E13.5 pregnant uterus and found significantly decreased uNK cells in Cxcl14{sup −/−} pregnant uteri compared with Cxcl14{sup +/−} pregnant uteri. To further explorer the molecular change in MLAp and DB after Cxcl14 knockout, we isolated the MLAp and DB from Cxcl14{sup +/+} and Cxcl14{sup −/−} pregnant uteri and performed microarray analysis. We found many genes were up and down regulated after Cxcl14 knockout. In conclusion, our results suggested the important function of Cxcl14 in uNK cells and the proper level of Cxcl14 protein were required to recruit NK cells to pregnant uterus.

  11. TIGIT expression levels on human NK cells correlate with functional heterogeneity among healthy individuals.

    PubMed

    Wang, Feng; Hou, Hongyan; Wu, Shiji; Tang, Qing; Liu, Weiyong; Huang, Min; Yin, Botao; Huang, Jing; Mao, Lie; Lu, Yanfang; Sun, Ziyong

    2015-10-01

    Human NK cells display extensive phenotypic and functional heterogeneity among healthy individuals, but the mechanism responsible for this variation is still largely unknown. Here, we show that a novel immune receptor, T-cell immunoglobulin and ITIM domain (TIGIT), is expressed preferentially on human NK cells but shows wide variation in its expression levels among healthy individuals. We found that the TIGIT expression level is related to the phenotypic and functional heterogeneity of NK cells, and that NK cells from healthy individuals can be divided into three categories according to TIGIT expression. NK cells with low levels of TIGIT expression show higher cytokine secretion capability, degranulation activity, and cytotoxic potential than NK cells with high levels of TIGIT expression. Blockade of the TIGIT pathway significantly increased NK-cell function, particularly in NK cells with high levels of TIGIT expression. We further observed that the TIGIT expression level was inversely correlated with the IFN-γ secretion capability of NK cells in patients with cancers and autoimmune diseases. Importantly, we propose a novel mechanism that links TIGIT expression with NK-cell functional heterogeneity, and this mechanism might partially explain why individuals have different susceptibilities to infection, autoimmune disease, and cancer.

  12. Prenatal exposure to cypermethrin modulates rat NK cell cytotoxic functions.

    PubMed

    Santoni, G; Cantalamessa, F; Mazzucca, L; Romagnoli, S; Piccoli, M

    1997-07-11

    The synthetic pyrethroid insecticide, cypermethrin, was given during gestation to pregnant rats by gavage in corn oil. Peripheral blood and spleen cytotoxic activity of dams and their offspring were then evaluated at different times (30, 60, 90, 120 days) after birth. Pups showed a significant increase in peripheral blood natural killer (NK) and antibody-dependent (ADCC) cytotoxic activity paralleled with a similar increase in the percentage of NK-RP1+ cells and decreased activity in the spleen. Pregnant cypermethrin-exposed dams showed no changes in peripheral blood or spleen cytotoxic function during the postnatal period. Overall, these results suggest that immunomodulation of cytotoxic activity observed in the offspring is likely attributable to a specific effect of cypermethrin administered during the prenatal period.

  13. NK Cells and Other Innate Lymphoid Cells in Hematopoietic Stem Cell Transplantation.

    PubMed

    Vacca, Paola; Montaldo, Elisa; Croxatto, Daniele; Moretta, Francesca; Bertaina, Alice; Vitale, Chiara; Locatelli, Franco; Mingari, Maria Cristina; Moretta, Lorenzo

    2016-01-01

    Natural killer (NK) cells play a major role in the T-cell depleted haploidentical hematopoietic stem cell transplantation (haplo-HSCT) to cure high-risk leukemias. NK cells belong to the expanding family of innate lymphoid cells (ILCs). At variance with NK cells, the other ILC populations (ILC1/2/3) are non-cytolytic, while they secrete different patterns of cytokines. ILCs provide host defenses against viruses, bacteria, and parasites, drive lymphoid organogenesis, and contribute to tissue remodeling. In haplo-HSCT patients, the extensive T-cell depletion is required to prevent graft-versus-host disease (GvHD) but increases risks of developing a wide range of life-threatening infections. However, these patients may rely on innate defenses that are reconstituted more rapidly than the adaptive ones. In this context, ILCs may represent important players in the early phases following transplantation. They may contribute to tissue homeostasis/remodeling and lymphoid tissue reconstitution. While the reconstitution of NK cell repertoire and its role in haplo-HSCT have been largely investigated, little information is available on ILCs. Of note, CD34(+) cells isolated from different sources of HSC may differentiate in vitro toward various ILC subsets. Moreover, cytokines released from leukemia blasts (e.g., IL-1β) may alter the proportions of NK cells and ILC3, suggesting the possibility that leukemia may skew the ILC repertoire. Further studies are required to define the timing of ILC development and their potential protective role after HSCT.

  14. Local Microenvironment Controls the Compartmentalization of NK Cell Responses during Systemic Inflammation in Mice.

    PubMed

    Rasid, Orhan; Ciulean, Ioana Sonya; Fitting, Catherine; Doyen, Noelle; Cavaillon, Jean-Marc

    2016-09-15

    Systemic inflammatory response syndrome is a whole-body reaction to a triggering insult that often results in life-threatening illness. Contributing to the development of this inflammatory cascade are numerous cellular partners, among which NK cells were shown to play a key role. Accumulating evidence points to organ-specific properties of systemic inflammation and NK cells. However, little is known about compartment-specific activation of NK cells during systemic inflammatory response syndrome or the relative contribution of NK cell-intrinsic properties and microenvironmental cues. In this study, we undertook a sequential characterization of NK responses in the spleen, lungs, bone marrow, peritoneum, and blood using a mouse model of endotoxemia. We report that, despite similar systemic dynamics of NK cell responses, expression of activation markers (CD69 and CD25) and effector molecules (IFN-γ, granzyme B, and IL-10) display organ-specific thresholds of maximum activation. Using adoptive transfers of spleen and lung NK cells, we found that these cells have the capacity to quickly adapt to a new environment and adjust their response levels to that of resident NK cells. This functional adaptation occurs without significant alterations in phenotype and independently of subpopulation-specific trafficking. Thus, using a dynamic in vivo-transfer system, to our knowledge our study is the first to report the compartmentalization of NK cells responses during systemic inflammation and to show that NK cell-intrinsic properties and microenvironmental cues are involved in this process, in a sequential manner.

  15. Prenatal allospecific NK cell tolerance hinges on instructive allorecognition through the activating receptor during development

    PubMed Central

    Alhajjat, Amir M.; Strong, Beverly S.; Lee, Amanda E.; Turner, Lucas E.; Wadhwani, Ram K.; Ortaldo, John R.; Heusel, Jonathan W.; Shaaban, Aimen F.

    2015-01-01

    Little is known about how the prenatal interaction between NK cells and alloantigens shapes the developing NK cell repertoire towards tolerance or immunity. Specifically, the effect on NK cell education arising from developmental co-recognition of alloantigens by activating and inhibitory receptors with shared specificity is uncharacterized. Using a murine prenatal transplantation model, we examined the manner in which this seemingly conflicting input affects NK cell licensing and repertoire formation in mixed hematopoietic chimeras. We found that prenatal NK cell tolerance arose from the elimination of phenotypically “hostile” NK cells that express an allospecific activating receptor without co-expressing any allospecific inhibitory receptors. Importantly, the checkpoint for the system appeared to occur centrally within the bone marrow during the final stage of NK cell maturation and hinged on the instructive recognition of allogeneic ligand by the activating receptor rather than through the inhibitory receptor as classically proposed. Residual non-deleted hostile NK cells expressing only the activating receptor exhibited an immature, anergic phenotype but retained the capacity to upregulate inhibitory receptor expression in peripheral sites. However, the potential for this adaptive change to occur was lost in developmentally mature chimeras. Collectively, these findings illuminate the intrinsic process in which developmental allorecognition through the activating receptor regulates the emergence of durable NK cell tolerance and establishes a new paradigm to fundamentally guide future investigations of prenatal NK cell allospecific education. PMID:26136432

  16. Evaluation of therapeutic effects of natural killer (NK) cell-based immunotherapy in mice using in vivo apoptosis bioimaging with a caspase-3 sensor.

    PubMed

    Lee, Ho Won; Singh, Thoudam Debraj; Lee, Sang-Woo; Ha, Jeoung-Hee; Rehemtulla, Alnawaz; Ahn, Byeong-Cheol; Jeon, Young Hyun; Lee, Jaetae

    2014-07-01

    Natural killer (NK) cell-based immunotherapy is a promising strategy for cancer treatment, and caspase-3 is an important effector molecule in NK cell-mediated apoptosis in cancers. Here, we evaluated the antitumor effects of NK cell-based immunotherapy by serial noninvasive imaging of apoptosis using a caspase-3 sensor in mice with human glioma xenografts. Human glioma cells expressing both a caspase-3 sensor as a surrogate marker for caspase-3 activation and Renilla luciferase (Rluc) as a surrogate marker for cell viability were established and referred to as D54-CR cells. Human NK92 cells were used as effector cells. Treatment with NK92 cells resulted in a time- and effector number-dependent increase in bioluminescence imaging (BLI) activity of the caspase-3 sensor in D54-CR cells in vitro. Caspase-3 activation by NK92 treatment was blocked by Z-VAD treatment in D54-CR cells. Transfusion of NK92 cells induced an increase of the BLI signal by caspase-3 activation in a dose- and time-dependent manner in D54-CR tumor-bearing mice but not in PBS-treated mice. Accordingly, sequential BLI with the Rluc reporter gene revealed marked retardation of tumor growth in the NK92-treatment group but not in the PBS-treatment group. These data suggest that noninvasive imaging of apoptosis with a caspase-3 sensor can be used as an effective tool for evaluation of therapeutic efficacy as well as for optimization of NK cell-based immunotherapy.-Lee, H. W., Singh, T. D., Lee, S.-W., Ha, J.-H., Rehemtulla, A., Ahn, B.-C., Jeon, Y.-H., Lee, J. Evaluation of therapeutic effects of natural killer (NK) cell-based immunotherapy in mice using in vivo apoptosis bioimaging with a caspase-3 sensor.

  17. Prognostic value of tumor infiltrating NK cells and macrophages in stage II+III esophageal cancer patients

    PubMed Central

    Zheng, Xiao; Shi, Liangrong; Wu, Changping; Jiang, Jingting

    2016-01-01

    The detailed understanding of the immunobiology of tumor microenvironment has recently translated into new therapeutic approach against human cancers. Besides the role of immune cells mediating adaptive immune responses, the tumor infiltrating components of the innate immune system including, neutrophils, mast cells, NK cells, and macrophages, also role importantly in anti-tumor immunity. In our present study, we retrospectively analyzed the prognostic value of the densities of tumor infiltrating NK cells and macrophages in esophageal cancer tissues derived from stage II+III patients. Our results showed that the density of the infiltrating NK cells in tumor stroma was significantly associated with nodal status. In addition, the densities of the infiltrating NK cells in tumor nest, and the infiltrating macrophages in tumor nest as well as in tumor stroma, were significantly associated with patients' postoperative prognoses. Furthermore, the combination of infiltrating NK cells in tumor nest and stroma, or the combination of infiltrating macrophages in tumor nest and stroma, could also be used as important prognostic tool in predicting the survival of the stage II+III esophageal cancer patients. PMID:27736796

  18. GATA3 induces human T-cell commitment by restraining Notch activity and repressing NK-cell fate

    PubMed Central

    Van de Walle, Inge; Dolens, Anne-Catherine; Durinck, Kaat; De Mulder, Katrien; Van Loocke, Wouter; Damle, Sagar; Waegemans, Els; De Medts, Jelle; Velghe, Imke; De Smedt, Magda; Vandekerckhove, Bart; Kerre, Tessa; Plum, Jean; Leclercq, Georges; Rothenberg, Ellen V.; Van Vlierberghe, Pieter; Speleman, Frank; Taghon, Tom

    2016-01-01

    The gradual reprogramming of haematopoietic precursors into the T-cell fate is characterized by at least two sequential developmental stages. Following Notch1-dependent T-cell lineage specification during which the first T-cell lineage genes are expressed and myeloid and dendritic cell potential is lost, T-cell specific transcription factors subsequently induce T-cell commitment by repressing residual natural killer (NK)-cell potential. How these processes are regulated in human is poorly understood, especially since efficient T-cell lineage commitment requires a reduction in Notch signalling activity following T-cell specification. Here, we show that GATA3, in contrast to TCF1, controls human T-cell lineage commitment through direct regulation of three distinct processes: repression of NK-cell fate, upregulation of T-cell lineage genes to promote further differentiation and restraint of Notch activity. Repression of the Notch1 target gene DTX1 hereby is essential to prevent NK-cell differentiation. Thus, GATA3-mediated positive and negative feedback mechanisms control human T-cell lineage commitment. PMID:27048872

  19. Inhibition of ERK and proliferation in NK cell lines by soluble HLA-E released from Japanese encephalitis virus infected cells.

    PubMed

    Shwetank; Date, Onkar Sanjay; Carbone, Ennio; Manjunath, Ramanathapuram

    2014-11-01

    Productive infection of human endothelial cells with Japanese encephalitis virus (JEV), a single stranded RNA virus induces shedding of sHLA-E. We show here that sHLA-E that is released upon infection with this flavivirus can inhibit IL-2 and PMA mediated ERK 1/2 phosphorylation in two NK cell lines, Nishi and NKL. Virus infected or IFN-γ treated cell culture supernatants containing sHLA-E were found to partially inhibit IL-2 mediated induction of CD25 molecules on NKL cells. It was also found that sHLA-E could inhibit IL-2 induced [(3)H]-thymidine incorporation suggesting that, similar to cell surface expressed HLA-E, sHLA-E could also inhibit NK cell responses. Hence JEV-induced shedding of sHLA-E needs further investigation to better understand immune responses in JEV infections since it may have a role in viral evasion of NK cell responses.

  20. MHC Class I Expression by Donor Hematopoietic Stem Cells Is Required to Prevent NK Cell Attack in Allogeneic, but Not Syngeneic Recipient Mice.

    PubMed

    Hirata, Yuichi; Li, Hao-Wei; Takahashi, Kazuko; Ishii, Hiroshi; Sykes, Megan; Fujisaki, Joji

    2015-01-01

    NK cells resist engraftment of syngeneic and allogeneic bone marrow (BM) cells lacking major histocompatibility (MHC) class I molecules, suggesting a critical role for donor MHC class I molecules in preventing NK cell attack against donor hematopoietic stem and progenitor cells (HSPCs), and their derivatives. However, using high-resolution in vivo imaging, we demonstrated here that syngeneic MHC class I knockout (KO) donor HSPCs persist with the same survival frequencies as wild-type donor HSPCs. In contrast, syngeneic MHC class I KO differentiated hematopoietic cells and allogeneic MHC class I KO HSPCs were rejected in a manner that was significantly inhibited by NK cell depletion. In vivo time-lapse imaging demonstrated that mice receiving allogeneic MHC class I KO HSPCs showed a significant increase in NK cell motility and proliferation as well as frequencies of NK cell contact with and killing of HSPCs as compared to mice receiving wild-type HSPCs. The data indicate that donor MHC class I molecules are required to prevent NK cell-mediated rejection of syngeneic differentiated cells and allogeneic HSPCs, but not of syngeneic HSPCs.

  1. The Tyrosine Kinase Pyk-2/Raftk Regulates Natural Killer (Nk) Cell Cytotoxic Response, and Is Translocated and Activated upon Specific Target Cell Recognition and Killing

    PubMed Central

    Sancho, David; Nieto, Marta; Llano, Manuel; Rodríguez-Fernández, José L.; Tejedor, Reyes; Avraham, Shalom; Cabañas, Carlos; López-Botet, Miguel; Sánchez-Madrid, Francisco

    2000-01-01

    The compartmentalization of plasma membrane proteins has a key role in regulation of lymphocyte activation and development of immunity. We found that the proline-rich tyrosine kinase-2 (PYK-2/RAFTK) colocalized with the microtubule-organizing center (MTOC) at the trailing edge of migrating natural killer (NK) cells. When polyclonal NK cells bound to K562 targets, PYK-2 translocated to the area of NK–target cell interaction. The specificity of this process was assessed with NK cell clones bearing activatory or inhibitory forms of CD94/NKG2. The translocation of PYK-2, MTOC, and paxillin to the area of NK–target cell contact was regulated upon specific recognition of target cells through NK cell receptors, controlling target cell killing. Furthermore, parallel in vitro kinase assays showed that PYK-2 was activated in response to signals that specifically triggered its translocation and NK cell mediated cytotoxicity. The overexpression of both the wt and a dominant-negative mutant of PYK-2, but not ZAP-70 wt, prevented the specific translocation of the MTOC and paxillin, and blocked the cytotoxic response of NK cells. Our data indicate that subcellular compartmentalization of PYK-2 correlates with effective signal transduction. Furthermore, they also suggest an important role for PYK-2 on the assembly of the signaling complexes that regulate the cytotoxic response. PMID:10851022

  2. Complexes of DNA with the Antimicrobial Peptide LL37 Augment NK Cell Functions by Inducing Type I Interferon Production from Circulating Monocytes and Plasmacytoid Predendritic Cells.

    PubMed

    Pinegin, Boris V; Pashenkov, Mikhail V; Kulakov, Vladimir V; Murugin, Vladimir V; Zhmak, Maxim N

    2015-11-01

    The cationic antimicrobial peptide, LL37, forms electrostatic complexes with DNA (LL37-DNA), which are potent activators of circulating plasmacytoid predendritic cells (ppDCs) and monocytes. However, the effects of LL37-DNA on other immune cell types, such as NK cells, are poorly characterized. In this study, we show that complexes of human genomic DNA (hgDNA) or synthetic double-stranded oligodeoxynucleotides with LL37 strongly enhance natural cytotoxicity of human peripheral blood mononuclear cells (PBMCs) upon an overnight culture, whereas hgDNA alone has no effect, and LL37 alone is moderately active. LL37-DNA complexes potentiate degranulation of, and interferon (IFN)-γ production by, NK cells upon subsequent encounter of K562 target cells. The complexes do not influence percentages of NK cells among PBMCs or the expression of cytotoxic proteins by NK cells. Using neutralizing anticytokine antibodies and immunomagnetic depletion of different subpopulations of PBMCs, we found that the effect of LL37-DNA on NK cells is indirect and mediated by type I IFNs produced by monocytes and, to a lesser extent, by ppDCs. We discuss possible roles of LL37-DNA complexes in the regulation of NK cell functions and in the treatment of cancer.

  3. MHC Class I Expression by Donor Hematopoietic Stem Cells Is Required to Prevent NK Cell Attack in Allogeneic, but Not Syngeneic Recipient Mice

    PubMed Central

    Hirata, Yuichi; Li, Hao-Wei; Takahashi, Kazuko; Ishii, Hiroshi; Sykes, Megan; Fujisaki, Joji

    2015-01-01

    NK cells resist engraftment of syngeneic and allogeneic bone marrow (BM) cells lacking major histocompatibility (MHC) class I molecules, suggesting a critical role for donor MHC class I molecules in preventing NK cell attack against donor hematopoietic stem and progenitor cells (HSPCs), and their derivatives. However, using high-resolution in vivo imaging, we demonstrated here that syngeneic MHC class I knockout (KO) donor HSPCs persist with the same survival frequencies as wild-type donor HSPCs. In contrast, syngeneic MHC class I KO differentiated hematopoietic cells and allogeneic MHC class I KO HSPCs were rejected in a manner that was significantly inhibited by NK cell depletion. In vivo time-lapse imaging demonstrated that mice receiving allogeneic MHC class I KO HSPCs showed a significant increase in NK cell motility and proliferation as well as frequencies of NK cell contact with and killing of HSPCs as compared to mice receiving wild-type HSPCs. The data indicate that donor MHC class I molecules are required to prevent NK cell-mediated rejection of syngeneic differentiated cells and allogeneic HSPCs, but not of syngeneic HSPCs. PMID:26544200

  4. High-efficiency lysis of cervical cancer by allogeneic NK cells derived from umbilical cord progenitors is independent of HLA status.

    PubMed

    Veluchamy, John P; Heeren, A Marijne; Spanholtz, Jan; van Eendenburg, Jaap D H; Heideman, Daniëlle A M; Kenter, Gemma G; Verheul, Henk M; van der Vliet, Hans J; Jordanova, Ekaterina S; de Gruijl, Tanja D

    2017-01-01

    Down-regulation of HLA in tumor cells, low numbers and dysfunctionality of NK cells are commonly observed in patients with end-stage cervical cancer. Adoptive transfer of high numbers of cytotoxic NK cells might be a promising treatment approach in this setting. Here, we explored the cytotoxic efficacy on ten cervical cancer cell lines of activated allogeneic NK cells from two sources, i.e., peripheral blood (PBNK) with and without cetuximab (CET), a tumor-specific monoclonal antibody directed against EGFR, or derived from umbilical cord blood (UCB-NK). Whereas CET monotherapy was ineffective against the panel of cervical cancer cell lines, irrespective of their EGFR expression levels and despite their RAS (wt) status, it significantly enhanced the in vitro cytotoxic efficacy of activated PBNK (P = 0.002). Equally superior cytotoxicity over activated PBNK alone was achieved by UCB-NK (P < 0.001). Both PBNK- and UCB-NK-mediated cytotoxic activity was dependent on the NK-activating receptors natural killer group 2, member D receptor (NKG2D) and DNAX accessory molecule-1 (DNAM-1) (P < 0.05) and unrelated to expression levels of the inhibitory receptors HLA-E and/or HLA-G. Most strikingly, whereas the PBNK's cytotoxic activity was inversely correlated with HLA-ABC levels (P = 0.036), PBNK + CET and UCB-NK cytotoxicity were entirely independent of HLA-ABC expression. In conclusion, this study provides a rationale to initiate a clinical trial for cervical cancer with adoptively transferred allogeneic NK cells, employing either UCB-NK or PBNK + CET for EGFR-expressing tumors. Adoptive transfer of UCB-NK might serve as a generally applicable treatment for cervical cancer, enabled by HLA-, histology- and HPV-independent killing mechanisms.

  5. A fatal cytokine-induced systemic inflammatory response reveals a critical role for NK cells.

    PubMed

    Carson, W E; Yu, H; Dierksheide, J; Pfeffer, K; Bouchard, P; Clark, R; Durbin, J; Baldwin, A S; Peschon, J; Johnson, P R; Ku, G; Baumann, H; Caligiuri, M A

    1999-04-15

    The mechanism of cytokine-induced shock remains poorly understood. The combination of IL-2 and IL-12 has synergistic antitumor activity in vivo, yet has been associated with significant toxicity. We examined the effects of IL-2 plus IL-12 in a murine model and found that the daily, simultaneous administration of IL-2 and IL-12 resulted in shock and 100% mortality within 4 to 12 days depending on the strain employed. Mice treated with IL-2 plus IL-12 exhibited NK cell apoptosis, pulmonary edema, degenerative lesions of the gastrointestinal tract, and elevated serum levels of proinflammatory cytokines and acute phase reactants. The actions of TNF-alpha, IFN-gamma, macrophage-inflammatory protein-1alpha, IL-1, IL-1-converting enzyme, Fas, perforin, inducible nitric oxide synthase, and STAT1 did not contribute to the observed toxicity, nor did B or T cells. However, toxicity and death from treatment with IL-2 plus IL-12 could be completely abrogated by elimination of NK cells. These results suggest that the fatal systemic inflammatory response induced by this cytokine treatment is critically dependent upon NK cells, but does not appear to be mediated by the known effector molecules of this cellular compartment. These data may provide insight into the pathogenesis of cytokine-induced shock in humans.

  6. A novel TLR7 agonist reverses NK cell anergy and cures RMA-S lymphoma-bearing mice.

    PubMed

    Wiedemann, Gabriela Maria; Jacobi, Severin Johannes; Chaloupka, Michael; Krächan, Angelina; Hamm, Svetlana; Strobl, Stefan; Baumgartner, Roland; Rothenfusser, Simon; Duewell, Peter; Endres, Stefan; Kobold, Sebastian

    2016-07-01

    Toll-like receptor 7 (TLR7) agonists are potent immune stimulants able to overcome cancer-associated immune suppression. Due to dose-limiting systemic toxicities, only the topically applied TLR7 agonist (imiquimod) has been approved for therapy of skin tumors. There is a need for TLR7-activating compounds with equivalent efficacy but less toxicity. SC1, a novel small molecule agonist for TLR7, is a potent type-1 interferon inducer, comparable to the reference TLR7 agonist resiquimod, yet with lower induction of proinflammatory cytokines. In vivo, SC1 activates NK cells in a TLR7-dependent manner. Mice bearing the NK cell-sensitive lymphoma RMA-S are cured by repeated s. c. administrations of SC1 as efficiently as by the administration of resiquimod. No relevant toxicities were observed. Mechanistically, SC1 reverses NK cell anergy and restores NK cell-mediated tumor cell killing in an IFN-α-dependent manner. TLR7 targeting by SC1-based compounds may form an attractive strategy to activate NK cell responses for cancer therapy.

  7. Flow Cytometry-based Assay for the Monitoring of NK Cell Functions.

    PubMed

    Tognarelli, Sara; Jacobs, Benedikt; Staiger, Nina; Ullrich, Evelyn

    2016-10-30

    Natural killer (NK) cells are an important part of the human tumor immune surveillance system. NK cells are able to distinguish between healthy and virus-infected or malignantly transformed cells due to a set of germline encoded inhibitory and activating receptors. Upon virus or tumor cell recognition a variety of different NK cell functions are initiated including cytotoxicity against the target cell as well as cytokine and chemokine production leading to the activation of other immune cells. It has been demonstrated that accurate NK cell functions are crucial for the treatment outcome of different virus infections and malignant diseases. Here a simple and reliable method is described to analyze different NK cell functions using a flow cytometry-based assay. NK cell functions can be evaluated not only for the whole NK cell population, but also for different NK cell subsets. This technique enables scientists to easily study NK cell functions in healthy donors or patients in order to reveal their impact on different malignancies and to further discover new therapeutic strategies.

  8. Genetic Manipulation of NK Cells for Cancer Immunotherapy: Techniques and Clinical Implications

    PubMed Central

    Carlsten, Mattias; Childs, Richard W.

    2015-01-01

    Given their rapid and efficient capacity to recognize and kill tumor cells, natural killer (NK) cells represent a unique immune cell to genetically reprogram in an effort to improve the outcome of cell-based cancer immunotherapy. However, technical and biological challenges associated with gene delivery into NK cells have significantly tempered this approach. Recent advances in viral transduction and electroporation have now allowed detailed characterization of genetically modified NK cells and provided a better understanding for how these cells can be utilized in the clinic to optimize their capacity to induce tumor regression in vivo. Improving NK cell persistence in vivo via autocrine IL-2 and IL-15 stimulation, enhancing tumor targeting by silencing inhibitory NK cell receptors such as NKG2A, and redirecting tumor killing via chimeric antigen receptors, all represent approaches that hold promise in preclinical studies. This review focuses on available methods for genetic reprograming of NK cells and the advantages and challenges associated with each method. It also gives an overview of strategies for genetic reprograming of NK cells that have been evaluated to date and an outlook on how these strategies may be best utilized in clinical protocols. With the recent advances in our understanding of the complex biological networks that regulate the ability of NK cells to target and kill tumors in vivo, we foresee genetic engineering as an obligatory pathway required to exploit the full potential of NK-cell based immunotherapy in the clinic. PMID:26113846

  9. NK cell maturation to CD56(dim) subset associated with high levels of NCRs overrides the inhibitory effect of NKG2A and recovers impaired NK cell cytolytic potential after allogeneic hematopoietic stem cell transplantation.

    PubMed

    Ghasemzadeh, Mehran; Hosseini, Ehteramolsadat; Schwarer, Anthony P; Pourfathollah, Ali Akbar

    2016-04-01

    NK cell cytotoxicity against residual leukemic cells is crucial for immune system reconstitution after hematopoietic stem cell transplantation (HSCT). Since immune recovery after transplant still remains a major concern, we studied the counterbalance of NK cell receptors after HSCT and its importance in NK cell functional recovery. We investigated NK cell reconstitution in 27 acute leukemia patients at different time points following HLA-matched allogeneic HSCT compared to those of donors. NK cells were evaluated for their cytotoxicity in a standard (51)Cr-release assay against target cells and also analyzed for their receptors expression using flow cytometry. Early after transplant, we found higher percentage of CD56(bright) NK cells, increased levels of NKG2A and NCRs as well as decreased levels of KIRs expression on NK cells associated with an impaired cytotoxicity of these cells. All the abnormalities were normalized by one year after HSCT when CD56(bright) NK cells gradually differentiated into CD56(dim) subset. Collectively, we confirmed a gradual increase of CD56(dim) NK cells expressing NCRs with the significant decrease in NKG2A expression on NK cells. This finding was also associated with the recovery of NK cell cytotoxicity that suggests an important role for the kinetics of NK cell receptors during cell maturation in HSCT outcome.

  10. 19F-MRI for monitoring human NK cells in vivo

    PubMed Central

    Bouchlaka, Myriam N.; Ludwig, Kai D.; Gordon, Jeremy W.; Kutz, Matthew P.; Bednarz, Bryan P.; Fain, Sean B.; Capitini, Christian M.

    2016-01-01

    ABSTRACT The availability of clinical-grade cytokines and artificial antigen-presenting cells has accelerated interest in using natural killer (NK) cells as adoptive cellular therapy (ACT) for cancer. One of the technological shortcomings of translating therapies from animal models to clinical application is the inability to effectively and non-invasively track these cells after infusion in patients. We have optimized the nonradioactive isotope fluorine-19 (19F) as a means to label and track NK cells in preclinical models using magnetic resonance imaging (MRI). Human NK cells were expanded with interleukin (IL)-2 and labeled in vitro with increasing concentrations of 19F. Doses as low as 2 mg/mL 19F were detected by MRI. NK cell viability was only decreased at 8 mg/mL 19F. No effects on NK cell cytotoxicity against K562 leukemia cells were observed with 2, 4 or 8 mg/mL 19F. Higher doses of 19F, 4 mg/mL and 8 mg/mL, led to an improved 19F signal by MRI with 3 × 1011 19F atoms per NK cell. The 4 mg/mL 19F labeling had no effect on NK cell function via secretion of granzyme B or interferon gamma (IFNγ), compared to NK cells exposed to vehicle alone. 19F-labeled NK cells were detectable immediately by MRI after intratumoral injection in NSG mice and up to day 8. When 19F-labeled NK cells were injected subcutaneously, we observed a loss of signal through time at the site of injection suggesting NK cell migration to distant organs. The 19F perfluorocarbon is a safe and effective reagent for monitoring the persistence and trafficking of NK cell infusions in vivo, and may have potential for developing novel imaging techniques to monitor ACT for cancer. PMID:27467963

  11. Hypoxic tumor-derived microvesicles negatively regulate NK cell function by a mechanism involving TGF-β and miR23a transfer

    PubMed Central

    Berchem, Guy; Noman, Muhammad Zaeem; Bosseler, Manon; Paggetti, Jerome; Baconnais, Sonia; Le cam, Eric; Nanbakhsh, Arash; Moussay, Etienne; Mami-Chouaib, Fathia; Janji, Bassam; Chouaib, Salem

    2016-01-01

    ABSTRACT Tumor-derived microvesicles (TD-MVs) are key mediators which are shed by cancer cells and can sensitize neighboring cells in the tumor microenvironment. TD-MVs are extracellular vesicles composed of exosomes and MVs and promote cancer invasion and metastasis. Intratumoral hypoxia is an integral component of all solid tumors. The relationship between hypoxic tumor-shed MVs and NK-mediated cytotoxicity remains unknown. In this paper, we reported that MVs derived from hypoxic tumor cells qualitatively differ from those derived from normoxic tumor cells. Using multiple tumor models, we showed that hypoxic MVs inhibit more NK cell function as compared to normoxic MVs. Hypoxic TD-MVs package two immunosuppressive factors involved in the impairment of natural killer (NK) cell cytotoxicity against different tumor cells in vitro and in vivo. We showed that following their uptake by NK cells, hypoxic TD-MVs transfer TGF-β1 to NK cells, decreasing the cell surface expression of the activating receptor NKG2D, thereby inhibiting NK cell function. MicroRNA profiling revealed the presence of high levels of miR-210 and miR-23a in hypoxic TD-MVs. We demonstrated that miR-23a in hypoxic TD-MVs operates as an additional immunomosuppressive factor, since it directly targets the expression of CD107a in NK cells. To our knowledge, this is the first study to show that hypoxic tumor cells by secreting MVs can educate NK cells and decrease their antitumor immune response. This study highlights the existence of a novel mechanism of immune suppression mediated by hypoxic TD-MVs and further improves our understanding of the immunosuppressive mechanisms prevailing in the hypoxic tumor microenvironment. PMID:27141372

  12. Enhanced NK cell adoptive antitumor effects against breast cancer in vitro via blockade of the transforming growth factor-β signaling pathway

    PubMed Central

    Zhao, Yue; Hu, Jinyue; Li, Rongguo; Song, Jian; Kang, Yujuan; Liu, Si; Zhang, Dongwei

    2015-01-01

    Natural killer (NK) cells have great potential for improving cancer immunotherapy. Adoptive NK cell transfer, an adoptive immunotherapy, represents a promising nontoxic anticancer therapy. However, existing data indicate that tumor cells can effectively escape NK cell-mediated apoptosis through immunosuppressive effects in the tumor microenvironment, and the therapeutic activity of adoptive NK cell transfer is not as efficient as anticipated. Transforming growth factor-beta (TGF-β) is a potent immunosuppressant. Genetic and epigenetic events that occur during mammary tumorigenesis circumvent the tumor-suppressing activity of TGF-β, thereby permitting late-stage breast cancer cells to acquire an invasive and metastatic phenotype in response to TGF-β. To block the TGF-β signaling pathway, NK cells were genetically modified with a dominant-negative TGF-β type II receptor by optimizing electroporation using the Amaxa Nucleofector system. These genetically modified NK cells were insensitive to TGF-β and resisted the suppressive effect of TGF-β on MCF-7 breast cancer cells in vitro. Our results demonstrate that blocking the TGF-β signaling pathway to modulate the tumor microenvironment can improve the antitumor activity of adoptive NK cells in vitro, thereby providing a new rationale for the treatment of breast cancer. PMID:26124672

  13. Experimental study on rat NK cell activity improvement by laser acupoint irradiation

    NASA Astrophysics Data System (ADS)

    Yang, Dongxiao; Chen, Xiufeng; Ruan, Buqing; Yang, Feng

    1998-08-01

    To study the improvement of the natural killer (NK) cell activity by semiconductor laser acupoint irradiation, rats were used in this experiment and were injected immunosuppressant in their abdomen. The immunoassay was made after the surface irradiation and inner irradiation at Baihui point by semiconductor laser. The NK cell activity is an important index of immunologic function. The results showed that the NK cell activity after laser acupoint irradiation was enhanced. This enhancement is relatively important in the clinical therapy of tumor.

  14. Prospective study of percutaneous cryoablation combined with allogenic NK cell immunotherapy for advanced renal cell cancer.

    PubMed

    Lin, Mao; Xu, Kecheng; Liang, Shuzhen; Wang, Xiaohua; Liang, Yinqing; Zhang, Mingjie; Chen, Jibing; Niu, LiZhi

    2017-03-05

    In this study, the clinical efficacy of cryosurgery combined with allogenic NK cell immunotherapy for advanced renal cell cancer was evaluated. From July to December 2016, we enrolled 60 patients who met the enrollment criteria and divided them into two groups: (1) the simple cryoablation group (n=30); and (2) the cryoablation combined with allogenic NK cells group (n=30). The clinical efficacy, quality of life, immune function, and other related indicators were evaluated. Combining allogeneic NK cells with cryoablation had a synergistic effect, not only enhancing the immune function and improving the quality of life of the patients, but also significantly exhibiting good clinical efficacy of the patients. This study is the first clinical trial that has evaluated the safety and efficacy of allogenic NK cells combined with cryosurgery for the treatment of renal cell cancer.

  15. Functional analysis of NK cell subsets activated by 721.221 and K562 HLA-null cells.

    PubMed

    Lisovsky, Irene; Isitman, Gamze; Bruneau, Julie; Bernard, Nicole F

    2015-04-01

    HLA-null cell lines [721.221 (henceforth, 721) and K562] are often used to study NK cell activation. NK cells are innate immune lymphocytes that express a variety of stochastically expressed inhibitory and activating receptors. Although it is known that 721 and K562 have divergent origins, they have been used interchangeably to stimulate NK cells in many studies. We hypothesized that the differences between 721 and K562 cells may result in differential NK cell-activation patterns. In this report, we assessed all possible combinations of CD107a expression and IFN-γ and CCL4 secretion in total NK and 3DL1(+/-) NK cell populations induced by these 2 cell lines. 721 activates a significantly higher frequency of NK cells and 3DL1(+) NK cells than K562. The NK cell functional subsets that are stimulated to a higher degree by 721 than K562 include those secreting IFN-γ and/or CCL4. On the other hand, the functional subsets that include CD107 expression contribute to a higher proportion of the total NK cell response following stimulation with K562 than 721. These results have implications for the selection of HLA-null cell lines to use as NK cell stimuli in investigations of their role in infectious diseases, cancer, and transplantation.

  16. NK Cells: Key to Success of DC-Based Cancer Vaccines?

    PubMed Central

    Smits, Evelien L.J.M.; Berneman, Zwi N.; Van Tendeloo, Viggo F.I.

    2012-01-01

    The cytotoxic and regulatory antitumor functions of natural killer (NK) cells have become attractive targets for immunotherapy. Manipulation of specific NK cell functions and their reciprocal interactions with dendritic cells (DCs) might hold therapeutic promise. In this review, we focus on the engagement of NK cells in DC-based cancer vaccination strategies, providing a comprehensive overview of current in vivo experimental and clinical DC vaccination studies encompassing the monitoring of NK cells. From these studies, it is clear that NK cells play a key regulatory role in the generation of DC-induced antitumor immunity, favoring the concept that targeting both innate and adaptive immune mechanisms may synergistically promote clinical outcome. However, to date, DC vaccination trials are only infrequently accompanied by NK cell monitoring. Here, we discuss different strategies to improve DC vaccine preparations via exploitation of NK cells and provide a summary of relevant NK cell parameters for immune monitoring. We underscore that the design of DC-based cancer vaccines should include the evaluation of their NK cell stimulating potency both in the preclinical phase and in clinical trials. PMID:22907975

  17. Tim-3 pathway affects NK cell impairment in patients with active tuberculosis.

    PubMed

    Wang, Feng; Hou, Hongyan; Wu, Shiji; Tang, Qing; Huang, Min; Yin, Botao; Huang, Jing; Liu, Weiyong; Mao, Lie; Lu, Yanfang; Sun, Ziyong

    2015-12-01

    Active tuberculosis (TB) patients show impaired NK cell function, and the underlying mechanism remains largely unknown. In this study, we confirmed the decrease in activation, cytokine secretion, and degranulation potential of NK cells in active TB patients. We further investigated whether coinhibitory receptor Tim-3 was involved with impairment of NK cells. Our results revealed that the expression of Tim-3 on NK cells was increased in active TB patients. Tim-3 expression was inversely correlated with IL-12-stimualted IFN-γ production. Moreover, blocking the Tim-3 pathway restored IFN-γ secretion and degranulation of NK cells. Blocking this pathway also increased NK cell cytotoxicity against K562 target cells, and improved the ability of NK cells to control Mtb growth in monocyte-derived macrophages. The Tim-3 expression on NK cells was also observed to be significantly decreased in TB patients post-treatment. In this study, we have identified that Tim-3 is involved with NK cell impairment in TB patients.

  18. Loss of DNAM-1 ligand expression by acute myeloid leukemia cells renders them resistant to NK cell killing.

    PubMed

    Kearney, Conor J; Ramsbottom, Kelly M; Voskoboinik, Ilia; Darcy, Phillip K; Oliaro, Jane

    2016-08-01

    Acute myeloid leukemia (AML) is associated with poor natural killer (NK) cell function through aberrant expression of NK-cell-activating receptors and their ligands on tumor cells. These alterations are thought to promote formation of inhibitory NK-target cell synapses, in which killer cell degranulation is attenuated. Allogeneic stem cell transplantation can be effective in treating AML, through restoration of NK cell lytic activity. Similarly, agents that augment NK-cell-activating signals within the immunological synapse may provide some therapeutic benefit. However, the receptor-ligand interactions that critically dictate NK cell function in AML remain undefined. Here, we demonstrate that CD112/CD155 expression is required for DNAM-1-dependent killing of AML cells. Indeed, the low, or absent, expression of CD112/CD155 on multiple AML cell lines resulted in failure to stimulate optimal NK cell function. Importantly, isolated clones with low CD112/155 expression were resistant to NK cell killing while those expressing abundant levels of CD112/155 were highly susceptible. Attenuated NK cell killing in the absence of CD112/CD155 originated from decreased NK-target cell conjugation. Furthermore, we reveal by time-lapse microscopy, a significant increase in NK cell 'failed killing' in the absence of DNAM-1 ligands. Consequently, NK cells preferentially lysed ligand-expressing cells within heterogeneous populations, driving clonal selection of CD112/CD155-negative blasts upon NK cell attack. Taken together, we identify reduced CD155 expression as a major NK cell escape mechanism in AML and an opportunity for targeted immunotherapy.

  19. Prolonged contact with dendritic cells turns lymph node-resident NK cells into anti-tumor effectors.

    PubMed

    Mingozzi, Francesca; Spreafico, Roberto; Gorletta, Tatiana; Cigni, Clara; Di Gioia, Marco; Caccia, Michele; Sironi, Laura; Collini, Maddalena; Soncini, Matias; Rusconi, Michela; von Andrian, Ulrich H; Chirico, Giuseppe; Zanoni, Ivan; Granucci, Francesca

    2016-09-01

    Natural killer (NK) cells are critical players against tumors. The outcome of anti-tumor vaccination protocols depends on the efficiency of NK-cell activation, and efforts are constantly made to manipulate them for immunotherapeutic approaches. Thus, a better understanding of NK-cell activation dynamics is needed. NK-cell interactions with accessory cells and trafficking between secondary lymphoid organs and tumoral tissues remain poorly characterized. Here, we show that upon triggering innate immunity with lipopolysaccharide (LPS), NK cells are transiently activated, leave the lymph node, and infiltrate the tumor, delaying its growth. Interestingly, NK cells are not actively recruited at the draining lymph node early after LPS administration, but continue their regular homeostatic turnover. Therefore, NK cells resident in the lymph node at the time of LPS administration become activated and exert anti-tumor functions. NK-cell activation correlates with the establishment of prolonged interactions with dendritic cells (DCs) in lymph nodes, as observed by two-photon microscopy. Close DC and NK-cell contacts are essential for the localized delivery of DC-derived IL-18 to NK cells, a strict requirement in NK-cell activation.

  20. Characterization of the myeloid-derived suppressor cell subset regulated by NK cells in malignant lymphoma.

    PubMed

    Sato, Yusuke; Shimizu, Kanako; Shinga, Jun; Hidaka, Michihiro; Kawano, Fumio; Kakimi, Kazuhiro; Yamasaki, Satoru; Asakura, Miki; Fujii, Shin-Ichiro

    2015-03-01

    Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population with the ability to suppress immune responses and are currently classified into three distinct MDSC subsets: monocytic, granulocytic and non-monocytic, and non-granulocytic MDSCs. Although NK cells provide an important first-line defense against newly transformed cancer cells, it is unknown whether NK cells can regulate MDSC populations in the context of cancer. In this study, we initially found that the frequency of MDSCs in non-Hodgkin lymphoma (NHL) patients was increased and inversely correlated with that of NK cells, but not that of T cells. To investigate the regulation of MDSC subsets by NK cells, we used an EL4 murine lymphoma model and found the non-monocytic and non-granulocytic MDSC subset, i.e., Gr1(+)CD11b(+)Ly6G(med)Ly6C(med) MDSC, is increased after NK cell depletion. The MDSC population that expresses MHC class II, CD80, CD124, and CCR2 is regulated mainly by CD27(+)CD11b(+)NK cells. In addition, this MDSC subset produces some immunosuppressive cytokines, including IL-10 but not nitric oxide (NO) or arginase. We also examined two subsets of MDSCs (CD14(+)HLA-DR(-) and CD14(-) HLA-DR(-) MDSC) in NHL patients and found that higher IL-10-producing CD14(+)HLA-DR(-)MDSC subset can be seen in lymphoma patients with reduced NK cell frequency in peripheral blood. Our analyses of MDSCs in this study may enable a better understanding of how MDSCs manipulate the tumor microenvironment and are regulated by NK cells in patients with lymphoma.

  1. Characterization of the myeloid-derived suppressor cell subset regulated by NK cells in malignant lymphoma

    PubMed Central

    Sato, Yusuke; Shimizu, Kanako; Shinga, Jun; Hidaka, Michihiro; Kawano, Fumio; Kakimi, Kazuhiro; Yamasaki, Satoru; Asakura, Miki; Fujii, Shin-ichiro

    2015-01-01

    Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population with the ability to suppress immune responses and are currently classified into three distinct MDSC subsets: monocytic, granulocytic and non-monocytic, and non-granulocytic MDSCs. Although NK cells provide an important first-line defense against newly transformed cancer cells, it is unknown whether NK cells can regulate MDSC populations in the context of cancer. In this study, we initially found that the frequency of MDSCs in non-Hodgkin lymphoma (NHL) patients was increased and inversely correlated with that of NK cells, but not that of T cells. To investigate the regulation of MDSC subsets by NK cells, we used an EL4 murine lymphoma model and found the non-monocytic and non-granulocytic MDSC subset, i.e., Gr1+CD11b+Ly6GmedLy6Cmed MDSC, is increased after NK cell depletion. The MDSC population that expresses MHC class II, CD80, CD124, and CCR2 is regulated mainly by CD27+CD11b+NK cells. In addition, this MDSC subset produces some immunosuppressive cytokines, including IL-10 but not nitric oxide (NO) or arginase. We also examined two subsets of MDSCs (CD14+HLA-DR− and CD14− HLA-DR− MDSC) in NHL patients and found that higher IL-10-producing CD14+HLA-DR−MDSC subset can be seen in lymphoma patients with reduced NK cell frequency in peripheral blood. Our analyses of MDSCs in this study may enable a better understanding of how MDSCs manipulate the tumor microenvironment and are regulated by NK cells in patients with lymphoma. PMID:25949922

  2. Multiple effects of IL-21 on human NK cells in ex vivo expansion.

    PubMed

    Li, Qi; Ye, Lin-Jie; Ren, Hai-Long; Huyan, Ting; Li, Jing; Shi, Jun-Ling; Huang, Qing-Sheng

    2015-07-01

    Natural killer (NK) cells (CD56(+)CD3(-)) are large, granular immunocytes that play a very pivotal role in the anti-inflammatory response and tumor surveillance. As an ideal cytotoxic lymphocyte (CTL), NK cells have attracted much attention in clinical trials. However, an insufficient number and their limited life span are bottlenecks that limit the application of NK cells in adoptive immunotherapy. Interleukins such as IL-2, IL-15 and IL-18 are recognized as factors that stimulate NK cells and have been used in NK cells ex vivo expansion. Similar to IL-2 and IL-15, IL-21 is a common γ-chain cytokine that is important in NK cell activation, maturation and proliferation. The present study aims to assess the effects of membrane-bound and soluble IL-21 on primary human NK cells during ex vivo expansion. IL-21 was found to have multiple effects on NK cells, increasing their cytotoxicity in a concentration-dependent manner by up-regulating IFN-γ and Granzyme-B expression. Nevertheless, at a high concentration (50 ng/mL), IL-21 curtailed the life span of NK cells by significantly inducing apoptosis. Moreover, when treated with IL-21, the number of NKT (CD56(+)CD3(+)) cells increased among peripheral blood mononuclear cells (PBMCs) during ex vivo expansion in a concentration-dependent manner. IL-21 also promoted expanded cells to enter into S phase of the cell cycle during the first to second weeks of culture. All these results suggest that IL-21 has multiple effects on NK cell development and functions. More attention should be given to the dosage and multiple effects of IL-21 when it was applied to NK cells in ex vivo expansion.

  3. Folate-conjugated immunoglobulin targets melanoma tumor cells for NK cell effector functions.

    PubMed

    Skinner, Cassandra C; McMichael, Elizabeth L; Jaime-Ramirez, Alena C; Abrams, Zachary B; Lee, Robert J; Carson, William E

    2016-08-01

    The folate receptor (FR) is overexpressed on the vascular side of cancerous cells including those of the breast, ovaries, testes, and cervix. We hypothesized that a folate-conjugated immunoglobulin (F-IgG) would bind to the FR that is overexpressed on melanoma tumor cells to target these cells for lysis by natural killer (NK) cells. Folate receptor expression was confirmed in the Mel-39 (human melanoma) cell line by flow cytometry and immunoblot analysis using KB (human oral epithelial) and F01 (human melanoma) as a positive and a negative control, respectively. FR-positive and FR-negative cell lines were treated with F-IgG or control immunoglobulin G in the presence or absence of cytokines to determine NK cell ability to lyse FR-positive cell lines. NK cell activation was significantly upregulated and lysis of Mel 39 tumor cells increased following treatment with F-IgG compared with control immunoglobulin G at all effector : target (E : T) ratios (P<0.01). This trend further increased by NK cell stimulation with the activating cytokine interleukin-12. NK cell production of cytokines such as interferon-gamma, macrophage inflammatory protein 1α, and regulated on activation normal T-cell expressed and secreted (RANTES) was also significantly increased in response to costimulation with interleukin-12 stimulation and F-IgG-coated Mel 39 target cells compared with controls (P<0.01). In contrast, F-IgG did not bind to the FR-negative cell line F01 and had no significant effect on NK cell lysis or cytokine production. This research indicates the potential use of F-IgG for its ability to induce an immune response from NK cells against FR-positive melanoma tumor cells, which can be further increased by the addition of cytokines.

  4. Human Liver Stem Cells Suppress T-Cell Proliferation, NK Activity, and Dendritic Cell Differentiation

    PubMed Central

    Bruno, Stefania; Grange, Cristina; Tapparo, Marta; Pasquino, Chiara; Romagnoli, Renato; Dametto, Ennia; Amoroso, Antonio; Tetta, Ciro; Camussi, Giovanni

    2016-01-01

    Human liver stem cells (HLSCs) are a mesenchymal stromal cell-like population resident in the adult liver. Preclinical studies indicate that HLSCs could be a good candidate for cell therapy. The aim of the present study was to evaluate the immunogenicity and the immunomodulatory properties of HLSCs on T-lymphocytes, natural killer cells (NKs), and dendritic cells (DCs) in allogeneic experimental settings. We found that HLSCs inhibited T-cell proliferation by a mechanism independent of cell contact and dependent on the release of prostaglandin E2 (PGE2) and on indoleamine 2,3-dioxygenase activity. When compared with mesenchymal stromal cells (MSCs), HLSCs were more efficient in inhibiting T-cell proliferation. At variance with MSCs, HLSCs did not elicit NK degranulation. Moreover, HLSCs inhibited NK degranulation against K562, a NK-sensitive target, by a mechanism dependent on HLA-G release. When tested on DC generation from monocytes, HLSCs were found to impair DC differentiation and DCs ability to induce T-cell proliferation through PGE2. This study shows that HLSCs have immunomodulatory properties similar to MSCs, but, at variance with MSCs, they do not elicit a NK response. PMID:27127520

  5. [Activation of natural killer T cells by NK-4, a criptocyanine dye].

    PubMed

    Kunikata, Toshio; Kohno, Keizo; Ushio, Shimpei; Fukuda, Shigeharu

    2011-01-01

    We previously reported that oral administration of NK-4, a criptocyanine dye, enhances interleukin (IL)-12-depend- ent interferon (IFN)-γ production by lipopolysaccharide (LPS)-stimulated mouse splenocytes. These findings raised a possibility that NK-4 potentiated IFN-γ production by T cells, natural killer (NK) cells or natural killer T (NKT) cells in response to IL-12 produced by macrophage and dendritic cells. To explore this possibility, we first analyzed percentages of T, NK or NKT cells in splenocytes of mice that were administered NK-4 orally for three days. The percentage of NKT cells in splenocytes from NK-4-treated mice was significantly (p<0.05) increased compared to vehicle-treated mice. When splenocytes were stimulated with α-galactosylceramide (α-GalCer), an NKT cell ligand, IFN-γ production by splenocytes from NK-4-treated mice tended to increase, while no difference in the IL-4 production and proliferation were observed between the vehicle- and NK-4-treated mice. When IFN-γ/IL-4 ratios were calculated in individual mice, the ratios were significantly (p<0.05) elevated in NK-4-treated mice. Furthermore, IL-12 production by α-GalCer-stimulated splenocytes from NK-4-treated mice was also significantly (p<0.05) increased. These results suggest that oral administration of NK-4 increases the population of type I NKT cells with potent IFN-γ-producing activities. Since IL-12 and IFN-γ have been shown to play important roles in anti-tumor immunity as well as in the defence against bacterial infection, our results further imply that NK-4 may provide a potential therapeutic tool in cancer immunotherapy.

  6. Effect of radiotherapy on the natural killer (NK)-cell activity of cancer patients

    SciTech Connect

    McGinnes, K.; Florence, J.; Penny, R.

    1987-05-01

    The aim of this study was to determine the effect of radiotherapy on peripheral blood natural killer (NK)-cell number and activity in 15 patients with cancer, prior to the commencement and at the completion of radiotherapy. The following observations were made. Prior to radiotherapy NK activity could not be correlated with the stage of malignancy. In all patients with advanced disease and with subnormal baseline NK activity, the outcome of radiotherapy was unfavorable. Following radiotherapy to sites including the mediastinum, patients had decreased NK activity compared with those receiving treatment to other sites. This decrease was not related to the dose of radiotherapy or stage of malignancy. The tumor response was favorable in most patients whose NK activity decreased as a result of radiotherapy. The decrease in NK activity may be associated with a decrease in the percentage of NK (N901) cells in the peripheral blood. The reduction in NK activity in those patients receiving mediastinal irradiation may be due to the large volume of blood which transits the field, so that the NK cells, or their more radiosensitive precursors, may be damaged and/or differentiation inhibited. Thus, these new observations show that radiotherapy does indeed affect the NK activity in cancer patients predominantly when the irradiation site includes the mediastinum.

  7. Laminin: a possible role as a mediator of natural cell-mediated functions

    SciTech Connect

    Laybourn, K.A.

    1986-01-01

    Natural Cell-mediated cytotoxicity is clearly important in regulating host response during tumorgenicity. Natural killer (NK), and Natural Cytotoxic (NC) lymphocytes responsible for mediating cytolysis, are subpopulations of non-B, non-T, nonphagocytic, nonadherent lymphocytes capable of spontaneously lysing a variety of tumor targets. Evidence is presented that laminin, a high molecular weight glycoprotein, is present on the surface of murine NK cells. In addition, NK sensitive tumor targets are able to bind laminin. This suggest that laminin participates as a ligand in the binding of NK cells to their tumor targets. The saturable binding of laminin by NK and NC sensitive tumor targets was shown by laminin-induced cell-cell aggregation/adherence, and /sup 125/I-laminin binding studies. Exogenous laminin inhibited NK cytotoxicity but not CTL cytotoxicity in vitro. In comparison, NK-resistant tumor cells bound little, if any exogenous laminin. Modulating NK activity in vivo prior to challenging mice with an inoculation of a murine fibrosarcoma, showed that elimination or activation of NK activity resulted in an increase or decrease in pulmonary metastases, respectively.

  8. Memory CD4+ T cells are required for optimal NK cell effector functions against the opportunistic fungal pathogen Pneumocystis murina.

    PubMed

    Kelly, Michelle N; Zheng, Mingquan; Ruan, Sanbao; Kolls, Jay; D'Souza, Alain; Shellito, Judd E

    2013-01-01

    Little is known about the role of NK cells or their interplay with other immune cells during opportunistic infections. Using our murine model of Pneumocystis pneumonia, we found that loss of NK cells during immunosuppression results in substantial Pneumocystis lung burden. During early infection of C57B/6 CD4(+) T cell-depleted mice, there were significantly fewer NK cells in the lung tissue compared with CD4(+) T cell-intact animals, and the NK cells present demonstrated decreased upregulation of the activation marker NKp46 and production of the effector cytokine, IFN-γ. Furthermore, coincubation studies revealed a significant increase in fungal killing when NK cells were combined with CD4(+) T cells compared with either cell alone, which was coincident with a significant increase in perforin production by NK cells. Finally, however, we found through adoptive transfer that memory CD4(+) T cells are required for significant NK cell upregulation of the activation marker NK group 2D and production of IFN-γ, granzyme B, and perforin during Pneumocystis infection. To the best of our knowledge, this study is the first to demonstrate a role for NK cells in immunity to Pneumocystis pneumonia, as well as to establish a functional relationship between CD4(+) T cells and NK cells in the host response to an opportunistic fungal pathogen.

  9. Induction of potent NK cell-dependent anti-myeloma cytotoxic T cells in response to combined mapatumumab and bortezomib.

    PubMed

    Neeson, Paul J; Hsu, Andy K; Chen, Yin R; Halse, Heloise M; Loh, Joanna; Cordy, Reece; Fielding, Kate; Davis, Joanne; Noske, Josh; Davenport, Alex J; Lindqvist-Gigg, Camilla A; Humphreys, Robin; Tai, Tsin; Prince, H Miles; Trapani, Joseph A; Smyth, Mark J; Ritchie, David S

    2015-09-01

    There is increasing evidence that some cancer therapies can promote tumor immunogenicity to boost the endogenous antitumor immune response. In this study, we used the novel combination of agonistic anti-TRAIL-R1 antibody (mapatumumab, Mapa) with low dose bortezomib (LDB) for this purpose. The combination induced profound myeloma cell apoptosis, greatly enhanced the uptake of myeloma cell apoptotic bodies by dendritic cell (DC) and induced anti-myeloma cytotoxicity by both CD8(+) T cells and NK cells. Cytotoxic lymphocyte expansion was detected within 24 h of commencing therapy and was maximized when myeloma-pulsed DC were co-treated with low dose bortezomib and mapatumumab (LDB+Mapa) in the presence of NK cells. This study shows that Mapa has two distinct but connected modes of action against multiple myeloma (MM). First, when combined with LDB, Mapa produced powerful myeloma cell apoptosis; secondly, it promoted DC priming and an NK cell-mediated expansion of anti-myeloma cytotoxic lymphocyte (CTL). Overall, this study indicates that Mapa can be used to drive potent anti-MM immune responses.

  10. NK Cell Proportion and Number Are Influenced by Genetic Loci on Chromosomes 8, 9, and 17.

    PubMed

    Pelletier, Adam-Nicolas; Guilbault, Lorie; Guimont-Desrochers, Fanny; Hillhouse, Erin E; Lesage, Sylvie

    2016-03-15

    NK cells play a crucial role in innate immunity due to their direct cytotoxicity toward tumors, virally infected cells, and stressed cells, and they also contribute to the orchestration of the adaptive response by their ability to produce immunoregulatory cytokines. In secondary lymphoid organs, NK cells compose the third most abundant lymphocyte subset after T cells and B cells. In this study, we perform an unbiased linkage analysis to determine the genetic loci that may limit the size of the NK cell compartment. Specifically, we exploit differences in NK cell proportion and absolute number between the C57BL/6 and the NOD mice. In addition to the previously identified linkage to chromosome 8, we find that a locus on chromosome 17, which encompasses the MHC locus, impacts NK cell number. Moreover, we identify a locus on mouse chromosome 9 that is strongly linked to the proportion and absolute number of NK cells. Using NOD congenic mice, we validate that both the MHC and the chromosome 9 loci influence the proportion and absolute number of NK cells. We have thus identified additional loci specifically linked to the proportion of NK cells and present some of the potential candidate genes comprised within these loci.

  11. Distinct roles for the actin nucleators Arp2/3 and hDia1 during NK-mediated cytotoxicity

    PubMed Central

    Butler, Boyd; Cooper, John A.

    2010-01-01

    Background Several actin nucleators, including Arp2/3 and various formins, control numerous cytoskeletal-based functions in vivo. Results We investigated the relative roles of these nucleators. As a model system, we used natural killer (NK) lymphocytes, which display a wide range of cytoskeletal-based functions that culminate in the lysis of target cells. NK cells lacking either Arp2/3 or the formin hDia1 were ineffective in target cell lysis, but for distinct reasons. Loss of Arp2/3 function led to defects in cells adhesion and actin assembly at the junction with the target cell (the lytic synapse). In contrast, loss of hDia1 did not disrupt actin assembly at the lytic synapse. Instead, loss of hDia1 led to perturbations in the microtubule cytoskeleton, including the targeting of microtubules to the lytic synapse. Conclusions These studies reveal novel distinctions and relationships among the functions of Arp2/3, formins and microtubules in cells. Notably, a formin mediates the capture of microtubules at the cell periphery. PMID:19913427

  12. Haploidentical Haematopoietic Stem Cell Transplantation: Role of NK Cells and Effect of Cytomegalovirus Infections.

    PubMed

    Della Chiesa, Mariella; Moretta, Lorenzo; Muccio, Letizia; Bertaina, Alice; Moretta, Francesca; Locatelli, Franco; Moretta, Alessandro

    2016-01-01

    Natural killer cells play an important role in the immune responses against cancer and viral infections. In addition, NK cells have been shown to exert a key role in haploidentical hematopoietic stem cell (HSC) transplantation for the therapy of high-risk leukemias. The anti-leukemia effect is mostly related to the presence of "alloreactive" NK cells, i.e., mature KIR(+) NK cells that express inhibitory KIR mismatched with HLA class I (KIR-L) of the patient. In addition, an important role is played by certain activating KIR (primarily, but not only, KIR2DS1) upon interaction with their HLA class I ligand (C2 alleles). In general, the presence of activating KIR correlates with a better prognosis. Beside the infusion of "pure" CD34(+) cells, a novel protocol has been recently developed in which depletion of αβ T cells and CD19(+) B cells makes it possible to infuse into the patient, together with donor CD34(+) HSCs, important effector cells including mature PB NK cells and γδ T cells. Recent studies revealed that cytomegalovirus (CMV) infection/reactivation may induce rapid NK cell maturation and greatly influence the NK receptor repertoire. The remarkable expansion of a subset expressing the activating receptor NKG2C, together with a more efficient virus-specific effector response after rechallenge with CMV (i.e., antigen specificity), and the longevity of the expanded population are all features consistent with an adaptive type of response and support the notion of a memory-like activity of NK cells.

  13. Intrinsic Contribution of Perforin to NK-Cell Homeostasis during Mouse Cytomegalovirus Infection.

    PubMed

    Arapović, Maja; Brizić, Ilija; Popović, Branka; Jurković, Slaven; Jordan, Stefan; Krmpotić, Astrid; Arapović, Jurica; Jonjić, Stipan

    2016-01-01

    In addition to their role as effector cells in virus control, natural killer (NK) cells have an immunoregulatory function in shaping the antiviral T-cell response. This function is further pronounced in perforin-deficient mice that show the enhanced NK-cell proliferation and cytokine secretion upon mouse cytomegalovirus (MCMV) infection. Here, we confirmed that stronger activation and maturation of NK cells in perforin-deficient mice correlates with higher MCMV load. To further characterize the immunoregulatory potential of perforin, we compared the response of NK cells that express or do not express perforin using bone-marrow chimeras. Our results demonstrated that the enhanced proliferation and maturation of NK cells in MCMV-infected bone-marrow chimeras is an intrinsic property of perforin-deficient NK cells. Thus, in addition to confirming that NK-cell proliferation is virus load dependent, our data extend this notion demonstrating that perforin plays an intrinsic role as a feedback mechanism in the regulation of NK-cell proliferation during viral infections.

  14. Lipoic acid stimulates cAMP production via the EP2 and EP4 prostanoid receptors and inhibits IFN gamma synthesis and cellular cytotoxicity in NK cells

    PubMed Central

    Salinthone, Sonemany; Schillace, Robynn V.; Marracci, Gail H.; Bourdette, Dennis N.; Carr, Daniel W.

    2008-01-01

    The antioxidant lipoic acid (LA) treats and prevents the animal model of multiple sclerosis (MS), experimental autoimmune encephalomyelitis (EAE). In an effort to understand the therapeutic potential of LA in MS, we sought to define the cellular mechanisms that mediate the effects of LA on human natural killer (NK) cells, which are important in innate immunity as the first line of defense against invading pathogens and tumor cells. We discovered that LA stimulates cAMP production in NK cells in a dose-dependent manner. Studies using pharmacological inhibitors and receptor transfection experiments indicate that LA stimulates cAMP production via activation of the EP2 and EP4 prostanoid receptors and adenylyl cyclase. In addition, LA suppressed interleukin (IL)-12/IL-18 induced IFNγ secretion and cytotoxicity in NK cells. These novel findings suggest that LA may inhibit NK cell function via the cAMP signaling pathway. PMID:18562016

  15. Lipoic acid stimulates cAMP production via the EP2 and EP4 prostanoid receptors and inhibits IFN gamma synthesis and cellular cytotoxicity in NK cells.

    PubMed

    Salinthone, Sonemany; Schillace, Robynn V; Marracci, Gail H; Bourdette, Dennis N; Carr, Daniel W

    2008-08-13

    The antioxidant lipoic acid (LA) treats and prevents the animal model of multiple sclerosis (MS), experimental autoimmune encephalomyelitis (EAE). In an effort to understand the therapeutic potential of LA in MS, we sought to define the cellular mechanisms that mediate the effects of LA on human natural killer (NK) cells, which are important in innate immunity as the first line of defense against invading pathogens and tumor cells. We discovered that LA stimulates cAMP production in NK cells in a dose-dependent manner. Studies using pharmacological inhibitors and receptor transfection experiments indicate that LA stimulates cAMP production via activation of the EP2 and EP4 prostanoid receptors and adenylyl cyclase. In addition, LA suppressed interleukin (IL)-12/IL-18 induced IFNgamma secretion and cytotoxicity in NK cells. These novel findings suggest that LA may inhibit NK cell function via the cAMP signaling pathway.

  16. Murine viral hepatitis involves NK cell depletion associated with virus-induced apoptosis

    PubMed Central

    LEHOUX, M; JACQUES, A; LUSIGNAN, S; LAMONTAGNE, L

    2004-01-01

    Mouse hepatitis virus type 3 (MHV3), a coronavirus, is an excellent animal model for the study of immunological disorders related to acute and chronic hepatitis. In this study, we have verified if the fulminant hepatitis induced by MHV3 could be related to an impairment of innate immunity. Groups of three C57BL/6 mice were infected with the pathogenic L2-MHV3 or attenuated YAC-MHV3 viruses, and the natural killer (NK) cell populations from liver, spleen and bone marrow were analysed. The percentage of intrahepatic NK1·1+T cell receptor (TCR)− cells did not increase while NK1·1+TCRinter cells decreased in both L2-MHV3- and YAC-MHV3-infected mice. Concurrently, splenic and myeloid NK1·1+ cells decreased in L2-MHV3-infected mice. However, the cytotoxic activity of NK cells increased in liver and decreased in bone marrow from pathogenic L2-MHV3-infected mice while no modification was detected in YAC-MHV3-infected mice. Flow cytometric analysis revealed that both normal and larger splenic or myeloid NK cells decreased more in pathogenic L2-MHV3-infected mice than in attenuated YAC-MHV3-infected mice. In vitro viral infections of interleukin (IL)-15-stimulated lymphoid cells from liver and bone marrow revealed that L2-MHV3 induced higher decreases in cell viability of NK1·1+ cells than the YAC-MHV3 variant. The NK cell decreases were due to the viral permissivity leading to cytopathic effects characterized by cell rounding, syncytia formation and apoptosis. Larger NK+ syncytia were observed in L2-MHV3-infected cells than in YAC-MHV3-infected cells. These results suggest that NK cell production is impaired by viral infection favouring fulminant hepatitis. PMID:15196242

  17. Impaired NK cell antiviral cytokine response against influenza virus in small-for-gestational-age neonates

    PubMed Central

    Li, Jinrong; Li, Hong; Mao, Huawei; Yu, Meixing; Yang, Fan; Feng, Ting; Fan, Yingying; Lu, Qiao; Shen, Chongyang; Yin, Zhongwei; Mao, Meng; Tu, Wenwei

    2013-01-01

    The neonates, particularly small-for-gestational-age (SGA) ones, are susceptible to various microbial infections. Natural killer (NK) cells are critical components of host innate immunity system and the main source of the inflammatory cytokines, which provide critical protection during the early phase of viral infections before the development of an appropriate adaptive immune response. However, little is known about the antiviral effects of NK cells in neonates especially the SGA population. Herein, a prospective descriptive study was performed to determine the differences of NK cell immunity among adults, appropriate-for gestational-age (AGA) and SGA neonates. Adults have much higher NK cell number in peripheral blood than that in cord blood from neonates. In response to influenza virus stimulation, neonatal NK cells, especially SGA baby cells, expressed significantly lower antiviral cytokines including perforin, interferon (IFN)-γ and tumor-necrosis factor (TNF)-α responses than adult NK cells. In addition, the antiviral cytokine responses of NK cells were positively correlated with neonatal birth weight. Our data suggested that the depressed antiviral activity and less frequency of NK cells are likely to be responsible for the high susceptibility to microbial infection in neonates, at least in part. Improving the function of innate immunity may provide a new way to defend virus infection. PMID:23872919

  18. Differential phenotypic and functional properties of liver-resident NK cells and mucosal ILC1s.

    PubMed

    Tang, Ling; Peng, Hui; Zhou, Jing; Chen, Yongyan; Wei, Haiming; Sun, Rui; Yokoyama, Wayne M; Tian, Zhigang

    2016-02-01

    Group 1 innate lymphoid cells (ILCs) consist of conventional natural killer (cNK) cells, tissue-resident NK cells and mucosal ILC1s. Recently identified liver-resident NK cells, which can mount contact hypersensitivity responses, and mucosal ILC1s that are involved in pathogenesis of colitis are distinct from cNK cells in several aspects, but the issue of how they are related to each other has not been clearly clarified. Here, we show that liver-resident NK cells and mucosal ILC1s have different phenotypes, as evidenced by distinct expression patterns of homing-associated molecules. Moreover, mucosal ILC1s exhibit tissue residency akin to liver-resident NK cells. Importantly, liver-resident NK cells express relative high levels of cytotoxic effector molecules, which are poorly expressed by mucosal ILC1s, and exhibit stronger cytotoxic activity compared with mucosal ILC1s. These results demonstrate differential phenotypic and functional characteristics of liver-resident NK cells and mucosal ILC1s, shedding new light on the diversity of ILC family.

  19. Simultaneous development of antibody-dependent cellular cytotoxicity (ADCC) and natural killer (NK) activity in irradiated mice reconstituted with bone marrow cells

    SciTech Connect

    Sihvola, M.; Hurme, M.

    1987-10-01

    Spleen cells from irradiated, bone marrow-reconstituted mice were tested for their ability to mediate antibody-dependent cellular cytotoxicity against P815 target (ADCC-P815), ADCC against sheep red blood cells (ADCC-SRBC), and natural killer (NK) activity judged as YAC-1 lysis at different times after bone marrow reconstitution. Donor-derived ADCC-P815 effectors were found to appear in the spleens 10-12 days after bone marrow reconstitution simultaneously with the appearance of donor-derived NK cells. NK cells recently derived from bone marrow are known to express the Thy-1 antigen; the phenotype of the ''early'' ADCC-P815 effectors was found to be the same as that of NK cells, i.e., Thy-1+, asialo-GM1+. These data suggest that ADCC-P815 effector cells belong to the NK cell population. ADCC-SRBC, in contrast to ADCC-P815 and NK activity, was already high on Day 7 after bone marrow reconstitution. However, it was mediated partly by recipient-derived effectors. ADCC-SRBC effectors were characterized to be different from ADCC-P815 effectors.

  20. EBV induces persistent NF-κB activation and contributes to survival of EBV-positive neoplastic T- or NK-cells

    PubMed Central

    Shibayama, Haruna; Yoshimori, Mayumi; Wang, Ludan; Saitoh, Yasunori; Uota, Shin; Yamaoka, Shoji; Koyama, Takatoshi; Shimizu, Norio; Yamamoto, Kouhei; Fujiwara, Shigeyoshi; Miura, Osamu

    2017-01-01

    Epstein–Barr virus (EBV) has been detected in several T- and NK-cell neoplasms such as extranodal NK/T-cell lymphoma nasal type, aggressive NK-cell leukemia, EBV-positive peripheral T-cell lymphoma, systemic EBV-positive T-cell lymphoma of childhood, and chronic active EBV infection (CAEBV). However, how this virus contributes to lymphomagenesis in T or NK cells remains largely unknown. Here, we examined NF-κB activation in EBV-positive T or NK cell lines, SNT8, SNT15, SNT16, SNK6, and primary EBV-positive and clonally proliferating T/NK cells obtained from the peripheral blood of patients with CAEBV. Western blotting, electrophoretic mobility shift assays, and immunofluorescent staining revealed persistent NF-κB activation in EBV-infected cell lines and primary cells from patients. Furthermore, we investigated the role of EBV in infected T cells. We performed an in vitro infection assay using MOLT4 cells infected with EBV. The infection directly induced NF-κB activation, promoted survival, and inhibited etoposide-induced apoptosis in MOLT4 cells. The luciferase assay suggested that LMP1 mediated NF-κB activation in MOLT4 cells. IMD-0354, a specific inhibitor of NF-κB that suppresses NF-κB activation in cell lines, inhibited cell survival and induced apoptosis. These results indicate that EBV induces NF-κB-mediated survival signals in T and NK cells, and therefore, may contribute to the lymphomagenesis of these cells. PMID:28346502

  1. NK cell responses to simian immunodeficiency virus vaginal exposure in naive and vaccinated rhesus macaques.

    PubMed

    Shang, Liang; Smith, Anthony J; Duan, Lijie; Perkey, Katherine E; Qu, Lucy; Wietgrefe, Stephen; Zupancic, Mary; Southern, Peter J; Masek-Hammerman, Katherine; Reeves, R Keith; Johnson, R Paul; Haase, Ashley T

    2014-07-01

    NK cell responses to HIV/SIV infection have been well studied in acute and chronic infected patients/monkeys, but little is known about NK cells during viral transmission, particularly in mucosal tissues. In this article, we report a systematic study of NK cell responses to high-dose vaginal exposure to SIVmac251 in the rhesus macaque female reproductive tract (FRT). Small numbers of NK cells were recruited into the FRT mucosa following vaginal inoculation. The influx of mucosal NK cells preceded local virus replication and peaked at 1 wk and, thus, was in an appropriate time frame to control an expanding population of infected cells at the portal of entry. However, NK cells were greatly outnumbered by recruited target cells that fuel local virus expansion and were spatially dissociated from SIV RNA+ cells at the major site of expansion of infected founder populations in the transition zone and adjoining endocervix. The number of NK cells in the FRT mucosa decreased rapidly in the second week, while the number of SIV RNA+ cells in the FRT reached its peak. Mucosal NK cells produced IFN-γ and MIP-1α/CCL3 but lacked several markers of activation and cytotoxicity, and this was correlated with inoculum-induced upregulation of the inhibitory ligand HLA-E and downregulation of the activating receptor CD122/IL-2Rβ. Examination of SIVΔnef-vaccinated monkeys suggested that recruitment of NK cells to the genital mucosa was not involved in vaccine-induced protection from vaginal challenge. In summary, our results suggest that NK cells play, at most, a limited role in defenses in the FRT against vaginal challenge.

  2. NK cells lacking FcεRIγ are associated with reduced liver damage in chronic hepatitis C virus infection.

    PubMed

    Oh, Jun S; Ali, Alaa K; Kim, Sungjin; Corsi, Daniel J; Cooper, Curtis L; Lee, Seung-Hwan

    2016-04-01

    A novel subset of human natural killer (NK) cells, which displays potent and broad antiviral responsiveness in concert with virus-specific antibodies, was recently uncovered in cytomegalovirus (CMV)+ individuals. This NK-cell subset (g-NK) was characterized by a deficiency in the expression of FcεRIγ adaptor protein and the long-lasting memory-like NK-cell phenotype, suggesting a role in chronic infections. This study investigates whether the g-NK-cell subset is associated with the magnitude of liver disease during chronic hepatitis C virus (HCV) infection. Analysis of g-NK-cell proportions and function in the PBMCs of healthy controls and chronic HCV subjects showed that chronic HCV subjects had slightly lower proportions of the g-NK-cell subset having similarly enhanced antibody-dependent cellular cytotoxicity responses compared to conventional NK cells. Notably, among CMV+ chronic HCV patients, lower levels of liver enzymes and fibrosis were found in those possessing g-NK cells. g-NK cells were predominant among the CD56(neg) NK cell population often found in chronic HCV patients, suggesting their involvement in immune response during HCV infection. For the first time, our findings indicate that the presence of the g-NK cells in CMV+ individuals is associated with amelioration of liver disease in chronic HCV infection, suggesting the beneficial roles of g-NK cells during a chronic infection.

  3. NK Cells with KIR2DS2 Immunogenotype Have a Functional Activation Advantage To Efficiently Kill Glioblastoma and Prolong Animal Survival

    PubMed Central

    Gras Navarro, Andrea; Kmiecik, Justyna; Leiss, Lina; Zelkowski, Mateusz; Engelsen, Agnete; Bruserud, Øystein; Zimmer, Jacques; Enger, Per Øyvind

    2014-01-01

    Glioblastomas (GBMs) are lethal brain cancers that are resistant to current therapies. We investigated the cytotoxicity of human allogeneic NK cells against patient-derived GBM in vitro and in vivo, as well as mechanisms mediating their efficacy. We demonstrate that KIR2DS2 immunogenotype NK cells were more potent killers, notwithstanding the absence of inhibitory killer Ig–like receptor (KIR)-HLA ligand mismatch. FACS-sorted and enriched KIR2DS2+ NK cell subpopulations retained significantly high levels of CD69 and CD16 when in contact with GBM cells at a 1:1 ratio and highly expressed CD107a and secreted more soluble CD137 and granzyme A. In contrast, KIR2DS2− immunogenotype donor NK cells were less cytotoxic against GBM and K562, and, similar to FACS-sorted or gated KIR2DS2− NK cells, significantly diminished CD16, CD107a, granzyme A, and CD69 when in contact with GBM cells. Furthermore, NK cell–mediated GBM killing in vitro depended upon the expression of ligands for the activating receptor NKG2D and was partially abrogated by Ab blockade. Treatment of GBM xenografts in NOD/SCID mice with NK cells from a KIR2DS2+ donor lacking inhibitory KIR-HLA ligand mismatch significantly prolonged the median survival to 163 d compared with vehicle controls (log-rank test, p = 0.0001), in contrast to 117.5 d (log-rank test, p = 0.0005) for NK cells with several inhibitory KIR-HLA ligand mismatches but lacking KIR2DS2 genotype. Significantly more CD56+CD16+ NK cells from a KIR2DS2+ donor survived in nontumor-bearing brains 3 wk after infusion compared with KIR2DS2− NK cells, independent of their proliferative capacity. In conclusion, KIR2DS2 identifies potent alloreactive NK cells against GBM that are mediated by commensurate, but dominant, activating signals. PMID:25381437

  4. Know Thyself: NK-Cell Inhibitory Receptors Prompt Self-Tolerance, Education, and Viral Control

    PubMed Central

    Nash, William T.; Teoh, Jeffrey; Wei, Hairong; Gamache, Awndre; Brown, Michael G.

    2014-01-01

    Natural killer (NK) cells provide essential protection against viral infections. One of the defining features of this lymphocyte population is the expression of a wide array of variable cell surface stimulatory and inhibitory NK receptors (sNKR and iNKR, respectively). The iNKR are particularly important in terms of NK-cell education. As receptors specific for MHC class I (MHC I) molecules, they are responsible for self-tolerance and adjusting NK-cell reactivity based on the expression level of self-MHC I. The end result of this education is twofold: (1) inhibitory signaling tunes the functional capacity of the NK cell, endowing greater potency with greater education, and (2) education on self allows the NK cell to detect aberrations in MHC I expression, a common occurrence during many viral infections. Many studies have indicated an important role for iNKR and MHC I in disease, making these receptors attractive targets for manipulating NK-cell reactivity in the clinic. A greater understanding of iNKR and their ability to regulate NK cells will provide a basis for future attempts at translating their potential utility into benefits for human health. PMID:24795719

  5. The Activating NKG2C Receptor Is Significantly Reduced in NK Cells after Allogeneic Stem Cell Transplantation in Patients with Severe Graft-versus-Host Disease.

    PubMed

    Kordelas, Lambros; Steckel, Nina-Kristin; Horn, Peter A; Beelen, Dietrich W; Rebmann, Vera

    2016-10-27

    Natural killer (NK) cells play a central role in the innate immune system. In allogeneic stem cell transplantation (alloSCT), alloreactive NK cells derived by the graft are discussed to mediate the elimination of leukemic cells and dendritic cells in the patient and thereby to reduce the risk for leukemic relapses and graft-versus-host reactions. The alloreactivity of NK cells is determined by various receptors including the activating CD94/NKG2C and the inhibitory CD94/NKG2A receptors, which both recognize the non-classical human leukocyte antigen E (HLA-E). Here we analyze the contribution of these receptors to NK cell alloreactivity in 26 patients over the course of the first year after alloSCT due to acute myeloid leukemia, myelodysplastic syndrome and T cell Non-Hodgkin-Lymphoma. Our results show that NK cells expressing the activating CD94/NKG2C receptor are significantly reduced in patients after alloSCT with severe acute and chronic graft-versus-host disease (GvHD). Moreover, the ratio of CD94/NKG2C to CD94/NKG2A was reduced in patients with severe acute and chronic GvHD after receiving an HLA-mismatched graft. Collectively, these results provide evidence for the first time that CD94/NKG2C is involved in GvHD prevention.

  6. Do NK-cell receptors and alloreactivity affect solid organ transplantation?

    PubMed

    Vilches, Carlos; Parham, Peter

    2006-12-01

    Although natural killer cells lyse targets without pre-sensitization, and in an MHC-unrestricted manner, they can also respond to healthy allogeneic cells of different MHC type. Such alloreactivity is a consequence of NK cells using clonally distributed, inhibitory MHC class I receptors to achieve tolerance to healthy autologous cells. Absence of an appropriate MHC class I ligand on an allogeneic cell erroneously informs the NK cell that the allogeneic cell has lost MHC class I expression and should be killed. Potential NK-cell allo-reactivities are common in non-HLA-identical hematopoietic cell transplants and can have both beneficial and detrimental effects. Less is known of NK-cell allo-reactivities in solid organ transplantation. In animal models NK cells are neither necessary nor sufficient for acute transplant rejection, but they can make a contribution by helping activate T cells. Genes encoding NK-cell receptors for polymorphic MHC class I molecules are also highly polymorphic, contributing to variability of the NK-cell repertoire and response in the human population. These receptors could represent intrinsic patient factors that influence the success of their transplanted solid organs.

  7. Conventional NK cells can produce IL-22 and promote host defense in Klebsiella pneumoniae pneumonia.

    PubMed

    Xu, Xin; Weiss, Ido D; Zhang, Hongwei H; Singh, Satya P; Wynn, Thomas A; Wilson, Mark S; Farber, Joshua M

    2014-02-15

    It was reported that host defense against pulmonary Klebsiella pneumoniae infection requires IL-22, which was proposed to be of T cell origin. Supporting a role for IL-22, we found that Il22(-/-) mice had decreased survival compared with wild-type mice after intratracheal infection with K. pneumoniae. Surprisingly, however, Rag2(-/-) mice did not differ from wild-type mice in survival or levels of IL-22 in the lungs postinfection with K. pneumoniae. In contrast, K. pneumoniae-infected Rag2(-/-)Il2rg(-/-) mice failed to produce IL-22. These data suggested a possible role for NK cells or other innate lymphoid cells in host defense and production of IL-22. Unlike NK cell-like innate lymphoid cells that produce IL-22 and display a surface phenotype of NK1.1(-)NKp46(+)CCR6(+), lung NK cells showed the conventional phenotype, NK1.1(+)NKp46(+)CCR6(-). Mice depleted of NK cells using anti-asialo GM1 showed decreased survival and higher lung bacterial counts, as well as increased dissemination of K. pneumoniae to blood and liver, compared with control-treated mice. NK cell depletion also led to decreased production of IL-22 in the lung. Within 1 d postinfection, although there was no increase in the number of lung NK cells, a subset of lung NK cells became competent to produce IL-22, and such cells were found in both wild-type and Rag2(-/-) mice. Our data suggest that, during pulmonary infection of mice with K. pneumoniae, conventional NK cells are required for optimal host defense, which includes the production of IL-22.

  8. Effects of a cloned cell line with NK activity on bone marrow transplants, tumour development and metastasis in vivo

    NASA Astrophysics Data System (ADS)

    Warner, John F.; Dennert, Gunther

    1982-11-01

    Natural killer (NK) cells cloned in vitro have been transferred into NK-deficient hosts. These cells have been shown to have a role in the rejection of allogeneic bone marrow grafts, resistance to both radiation-induced thymic leukaemia and challenge with melanoma tumour cells. It appears that NK cells have an important role in immune surveillance.

  9. Activating KIR2DS4 Is Expressed by Uterine NK Cells and Contributes to Successful Pregnancy

    PubMed Central

    Chazara, Olympe; Gardner, Lucy; Ivarsson, Martin A.; Farrell, Lydia E.; Xiong, Shiqiu; Hiby, Susan E.; Colucci, Francesco; Sharkey, Andrew M.

    2016-01-01

    Tissue-specific NK cells are abundant in the pregnant uterus and interact with invading placental trophoblast cells that transform the maternal arteries to increase the fetoplacental blood supply. Genetic case-control studies have implicated killer cell Ig-like receptor (KIR) genes and their HLA ligands in pregnancy disorders characterized by failure of trophoblast arterial transformation. Activating KIR2DS1 or KIR2DS5 (when located in the centromeric region as in Africans) lower the risk of disorders when there is a fetal HLA-C allele carrying a C2 epitope. In this study, we investigated another activating KIR, KIR2DS4, and provide genetic evidence for a similar effect when carried with KIR2DS1. KIR2DS4 is expressed by ∼45% of uterine NK (uNK) cells. Similarly to KIR2DS1, triggering of KIR2DS4 on uNK cells led to secretion of GM-CSF and other chemokines, known to promote placental trophoblast invasion. Additionally, XCL1 and CCL1, identified in a screen of 120 different cytokines, were consistently secreted upon activation of KIR2DS4 on uNK cells. Inhibitory KIR2DL5A, carried in linkage disequilibrium with KIR2DS1, is expressed by peripheral blood NK cells but not by uNK cells, highlighting the unique phenotype of uNK cells compared with peripheral blood NK cells. That KIR2DS4, KIR2DS1, and some alleles of KIR2DS5 contribute to successful pregnancy suggests that activation of uNK cells by KIR binding to HLA-C is a generic mechanism promoting trophoblast invasion into the decidua. PMID:27815424

  10. Mechanisms by Which Interleukin-12 Corrects Defective NK Cell Anticryptococcal Activity in HIV-Infected Patients

    PubMed Central

    Kyei, Stephen K.; Ogbomo, Henry; Li, ShuShun; Timm-McCann, Martina; Xiang, Richard F.; Huston, Shaunna M.; Ganguly, Anutosh; Colarusso, Pina; Gill, M. John

    2016-01-01

    ABSTRACT Cryptococcus neoformans is a pathogenic yeast and a leading cause of life-threatening meningitis in AIDS patients. Natural killer (NK) cells are important immune effector cells that directly recognize and kill C. neoformans via a perforin-dependent cytotoxic mechanism. We previously showed that NK cells from HIV-infected patients have aberrant anticryptococcal killing and that interleukin-12 (IL-12) restores the activity at least partially through restoration of NKp30. However, the mechanisms causing this defect or how IL-12 restores the function was unknown. By examining the sequential steps in NK cell killing of Cryptococcus, we found that NK cells from HIV-infected patients had defective binding of NK cells to C. neoformans. Moreover, those NK cells that bound to C. neoformans failed to polarize perforin-containing granules to the microbial synapse compared to healthy controls, suggesting that binding was insufficient to restore a defect in perforin polarization. We also identified lower expression of intracellular perforin and defective perforin release from NK cells of HIV-infected patients in response to C. neoformans. Importantly, treatment of NK cells from HIV-infected patients with IL-12 reversed the multiple defects in binding, granule polarization, perforin content, and perforin release and restored anticryptococcal activity. Thus, there are multiple defects in the cytolytic machinery of NK cells from HIV-infected patients, which cumulatively result in defective NK cell anticryptococcal activity, and each of these defects can be reversed with IL-12. PMID:27555306

  11. NK cytotoxicity against CD4+ T cells during HIV-1 infection: A gp41 peptide induces the expression of an NKp44 ligand

    PubMed Central

    Vieillard, Vincent; Strominger, Jack L.; Debré, Patrice

    2005-01-01

    HIV infection leads to a state of chronic immune activation and progressive deterioration in immune function, manifested most recognizably by the progressive depletion of CD4+ T cells. A substantial percentage of natural killer (NK) cells from patients with HIV infection are activated and express the natural cytotoxicity receptor (NCR) NKp44. Here we show that a cellular ligand for NKp44 (NKp44L) is expressed during HIV-1 infection and is correlated with both the progression of CD4+ T cell depletion and the increase of viral load. CD4+ T cells expressing this ligand are highly sensitive to the NK lysis activity mediated by NKp44+ NK cells. The expression of NKp44L is induced by the linear motif NH2-SWSNKS-COOH of the HIV-1 envelope gp41 protein. This highly conserved motif appears critical to the sharp increase in NK lysis of CD4+ T cells from HIV-infected patients. These studies strongly suggest that induction of NKp44L plays a key role in the lysis of CD4+ T cells by activated NK cells in HIV infection and consequently provide a framework for considering how HIV-1 may use NK cell immune surveillance to trigger CD4+ T cells. Understanding this mechanism may help to develop future therapeutic strategies and vaccines against HIV-1 infection. PMID:16046540

  12. An indirect role for NK cells in a CD4(+) T-cell-dependent mouse model of type I diabetes.

    PubMed

    Angstetra, Eveline; Graham, Kate L; Zhao, Yuxing; Irvin, Allison E; Elkerbout, Lorraine; Santamaria, Pere; Slattery, Robyn M; Kay, Thomas W; Thomas, Helen E

    2012-02-01

    CD8(+) T cells kill pancreatic β-cells in a cell-cell contact-dependent mechanism in the non-obese diabetic mouse. CD4(+) T lymphocytes are also able to kill pancreatic β-cells, but they do not directly contact β-cells and may use another cell type as the actual cytotoxic cell. Natural killer (NK) cells could have this role but it is uncertain whether they are cytotoxic towards β-cells. Therefore, the requirement for NK cells in β-cell destruction in the CD4-dependent T-cell antigen receptor transgenic NOD4.1 mice was examined. NK cells failed to kill β-cells in vitro, even in the absence of major histocompatibility complex class I. We observed only 9.7±1.1% of islet infiltrating NK cells from NOD4.1 mice expressing the degranulation marker CD107a. Diabetogenic CD4(+) T cells transferred disease to NODscid.IL2Rγ(-/-) mice lacking NK cells, indicating that NK cells do not contribute to β-cell death in vitro or in vivo. However, depletion of NK cells reduced diabetes incidence in NOD4.1 mice, suggesting that NK cells may help to maintain the right environment for cytotoxicity of effector cells.

  13. NK cells enhance dendritic cell response against parasite antigens via NKG2D pathway.

    PubMed

    Guan, Hongbing; Moretto, Magali; Bzik, David J; Gigley, Jason; Khan, Imtiaz A

    2007-07-01

    Recent studies have shown that NK-dendritic cell (DC) interaction plays an important role in the induction of immune response against tumors and certain viruses. Although the effect of this interaction is bidirectional, the mechanism or molecules involved in this cross-talk have not been identified. In this study, we report that coculture with NK cells causes several fold increase in IL-12 production by Toxoplasma gondii lysate Ag-pulsed DC. This interaction also leads to stronger priming of Ag-specific CD8+ T cell response by these cells. In vitro blockade of NKG2D, a molecule present on human and murine NK cells, neutralizes the NK cell-induced up-regulation of DC response. Moreover, treatment of infected animals with Ab to NKG2D receptor compromises the development of Ag-specific CD8+ T cell immunity and reduces their ability to clear parasites. These studies emphasize the critical role played by NKG2D in the NK-DC interaction, which apparently is important for the generation of robust CD8+ T cell immunity against intracellular pathogens. To the best of our knowledge, this is the first work that describes in vivo importance of NKG2D during natural infection.

  14. Oligosaccharide ligands for NKR-P1 protein activate NK cells and cytotoxicity

    NASA Astrophysics Data System (ADS)

    Bezouška, Karel; Yuen, Chun-Ting; O'Brien, Jacqui; Childs, Robert A.; Chai, Wengang; Lawson, Alexander M.; Drbal, Karel; Fišerová, Anna; Posíšil, Miloslav; Feizi, Ten

    1994-11-01

    A diversity of high-affinity Oligosaccharide ligands are identified for NKR-P1, a membrane protein on natural killer (NK) cells which contains an extracellular Ca2+-dependent lectin domain. Interactions of such oligosaccharides on the target cell surface with NKR-P1 on the killer cell surface are crucial both for target cell recognition and for delivery of stimulatory or inhibitory signals linked to the NK cytolytic machinery. NK-resistant tumour cells are rendered susceptible by preincubation with liposomes expressing NKR-P1 ligands, suggesting that purging of tumour or virally infected cells in vivo may be a therapeutic possibility.

  15. Nasal NK/T-cell lymphoma: epidemiology and pathogenesis

    PubMed Central

    Takakuwa, Tetsuya; Hongyo, Tadashi; Yang, Woo-Ick

    2008-01-01

    Nasal NK/T-cell lymphoma (NKTCL) is an uncommon disease, but usually shows a highly aggressive clinical course. The disease is much more frequent in Asian and Latin American countries than in Western countries, and is univers