Natural killer cell function predicts severe infection in kidney transplant recipients.
Dendle, Claire; Gan, Poh-Yi; Polkinghorne, Kevan R; Ngui, James; Stuart, Rhonda L; Kanellis, John; Thursky, Karin; Mulley, William R; Holdsworth, Stephen
2018-04-30
The aim of this study was to determine if natural killer cell number (CD3 - /CD16 ± /CD56 ± ) and cytotoxic killing function predicts severity and frequency of infection in kidney transplant recipients. A cohort of 168 kidney transplant recipients with stable graft function underwent assessment of natural killer cell number and functional killing capacity immediately prior to entry into this prospective study. Participants were followed for 2 years for development of severe infection, defined as hospitalization for infection. Area under receiver operating characteristic (AUROC) curves were used to evaluate the accuracy of natural killer cell number and function for predicting severe infection. Adjusted odds ratios were determined by logistic regression. Fifty-nine kidney transplant recipients (35%) developed severe infection and 7 (4%) died. Natural killer cell function was a better predictor of severe infection than natural killer cell number: AUROC 0.84 and 0.75, respectively (P = .018). Logistic regression demonstrated that after adjustment for age, transplant function, transplant duration, mycophenolate use, and increasing natural killer function (odds ratio [OR] 0.82, 95% confidence interval [CI] 0.74-0.90; P < .0001) but not natural killer number (OR 0.96, 95% CI 0.93-1.00; P = .051) remained significantly associated with a reduced likelihood of severe infection. Natural killer cell function predicts severe infection in kidney transplant recipients. © 2018 The American Society of Transplantation and the American Society of Transplant Surgeons.
IGF-1 promotes the development and cytotoxic activity of human NK cells
Ni, Fang; Sun, Rui; Fu, Binqing; Wang, Fuyan; Guo, Chuang; Tian, Zhigang; Wei, Haiming
2013-01-01
Insulin-like growth factor 1 (IGF-1) is a critical regulator of many physiological functions, ranging from longevity to immunity. However, little is known about the role of IGF-1 in natural killer cell development and function. Here, we identify an essential role for IGF-1 in the positive regulation of human natural killer cell development and cytotoxicity. Specifically, we show that human natural killer cells have the ability to produce IGF-1 and that differential endogenous IGF-1 expression leads to disparate cytotoxicity in human primary natural killer cells. Moreover, miR-483-3p is identified as a critical regulator of IGF-1 expression in natural killer cells. Overexpression of miR-483-3p has an effect similar to IGF-1 blockade and decreased natural killer cell cytotoxicity, whereas inhibition of miR-483-3p has the opposite effect, which is reversible with IGF-1 neutralizing antibody. These findings indicate that IGF-1 and miR-483-3p belong to a new class of natural killer cell functional modulators and strengthen the prominent role of IGF-1 in innate immunity. PMID:23403580
Fasting Enhances TRAIL-Mediated Liver Natural Killer Cell Activity via HSP70 Upregulation
Dang, Vu T. A.; Tanabe, Kazuaki; Tanaka, Yuka; Tokumoto, Noriaki; Misumi, Toshihiro; Saeki, Yoshihiro; Fujikuni, Nobuaki; Ohdan, Hideki
2014-01-01
Acute starvation, which is frequently observed in clinical practice, sometimes augments the cytolytic activity of natural killer cells against neoplastic cells. In this study, we investigated the molecular mechanisms underlying the enhancement of natural killer cell function by fasting in mice. The total number of liver resident natural killer cells in a unit weight of liver tissue obtained from C57BL/6J mice did not change after a 3-day fast, while the proportions of tumor necrosis factor–related apoptosis-inducing ligand (TRAIL)+ and CD69+ natural killer cells were significantly elevated (n = 7, p <0.01), as determined by flow cytometric analysis. Furthermore, we found that TRAIL− natural killer cells that were adoptively transferred into Rag-2−/− γ chain−/− mice could convert into TRAIL+ natural killer cells in fasted mice at a higher proportion than in fed mice. Liver natural killer cells also showed high TRAIL-mediated antitumor function in response to 3-day fasting. Since these fasted mice highly expressed heat shock protein 70 (n = 7, p <0.05) in liver tissues, as determined by western blot, the role of this protein in natural killer cell activation was investigated. Treatment of liver lymphocytes with 50 µg/mL of recombinant heat shock protein 70 led to the upregulation of both TRAIL and CD69 in liver natural killer cells (n = 6, p <0.05). In addition, HSP70 neutralization by intraperitoneally injecting an anti- heat shock protein 70 monoclonal antibody into mice prior to fasting led to the downregulation of TRAIL expression (n = 6, p <0.05). These findings indicate that acute fasting enhances TRAIL-mediated liver natural killer cell activity against neoplastic cells through upregulation of heat shock protein 70. PMID:25356750
Rea, Delphine; Henry, Guylaine; Khaznadar, Zena; Etienne, Gabriel; Guilhot, François; Nicolini, Franck; Guilhot, Joelle; Rousselot, Philippe; Huguet, Françoise; Legros, Laurence; Gardembas, Martine; Dubruille, Viviane; Guerci-Bresler, Agnès; Charbonnier, Aude; Maloisel, Frédéric; Ianotto, Jean-Christophe; Villemagne, Bruno; Mahon, François-Xavier; Moins-Teisserenc, Hélène; Dulphy, Nicolas; Toubert, Antoine
2017-08-01
Despite persistence of leukemic stem cells, patients with chronic myeloid leukemia who achieve and maintain deep molecular responses may successfully stop the tyrosine kinase inhibitor imatinib. However, questions remain unanswered regarding the biological basis of molecular relapse after imatinib cessation. In IMMUNOSTIM, we monitored 51 patients from the French Stop IMatinib trial for peripheral blood T cells and natural killer cells. Molecular relapse-free survival at 24 months was 45.1% (95% CI: 31.44%-58.75%). At the time of imatinib discontinuation, non-relapsing patients had significantly higher numbers of natural killer cells of the cytotoxic CD56 dim subset than had relapsing patients, while CD56 bright natural killer cells, T cells and their subsets did not differ significantly. Furthermore, the CD56 dim natural killer-cell count was an independent prognostic factor of molecular-relapse free survival in a multivariate analysis. However, expression of natural killer-cell activating receptors, BCR-ABL1 + leukemia cell line K562-specific degranulation and cytokine-induced interferon-gamma secretion were decreased in non-relapsing and relapsing patients as compared with healthy individuals. After imatinib cessation, the natural killer-cell count increased significantly and stayed higher in non-relapsing patients than in relapsing patients, while receptor expression and functional properties remained unchanged. Altogether, our results suggest that natural killer cells may play a role in controlling leukemia-initiating cells at the origin of relapse after imatinib cessation, provided that these cells are numerous enough to compensate for their functional defects. Further research will decipher mechanisms underlying functional differences between natural killer cells from patients and healthy individuals and evaluate the potential interest of immunostimulatory approaches in tyrosine kinase inhibitor discontinuation strategies. (ClinicalTrial.gov Identifier NCT00478985) . Copyright© 2017 Ferrata Storti Foundation.
Chromatin organization as an indicator of glucocorticoid induced natural killer cell dysfunction.
Misale, Michael S; Witek Janusek, Linda; Tell, Dina; Mathews, Herbert L
2018-01-01
It is well-established that psychological distress reduces natural killer cell immune function and that this reduction can be due to the stress-induced release of glucocorticoids. Glucocorticoids are known to alter epigenetic marks associated with immune effector loci, and are also known to influence chromatin organization. The purpose of this investigation was to assess the effect of glucocorticoids on natural killer cell chromatin organization and to determine the relationship of chromatin organization to natural killer cell effector function, e.g. interferon gamma production. Interferon gamma production is the prototypic cytokine produced by natural killer cells and is known to modulate both innate and adaptive immunity. Glucocorticoid treatment of human peripheral blood mononuclear cells resulted in a significant reduction in interferon gamma production. Glucocorticoid treatment also resulted in a demonstrable natural killer cell nuclear phenotype. This phenotype was localization of the histone, post-translational epigenetic mark, H3K27me3, to the nuclear periphery. Peripheral nuclear localization of H3K27me3 was directly related to cellular levels of interferon gamma. This nuclear phenotype was determined by direct visual inspection and by use of an automated, high through-put technology, the Amnis ImageStream. This technology combines the per-cell information content provided by standard microscopy with the statistical significance afforded by large sample sizes common to standard flow cytometry. Most importantly, this technology provides for a direct assessment of the localization of signal intensity within individual cells. The results demonstrate glucocorticoids to dysregulate natural killer cell function at least in part through altered H3K27me3 nuclear organization and demonstrate H3K27me3 chromatin organization to be a predictive indicator of glucocorticoid induced immune dysregulation of natural killer cells. Copyright © 2017 Elsevier Inc. All rights reserved.
Espinoza, J. Luis; Takami, Akiyoshi; Yoshioka, Katsuji; Nakata, Katsuya; Sato, Tokiharu; Kasahara, Yoshihito; Nakao, Shinji
2012-01-01
Background NKG2D is an activating receptor expressed by natural killer and T cells, which have crucial functions in tumor and microbial immunosurveillance. Several cytokines have been identified as modulators of NKG2D receptor expression. However, little is known about NKG2D gene regulation. In this study, we found that microRNA 1245 attenuated the expression of NKG2D in natural killer cells. Design and Methods We investigated the potential interactions between the 3′-untranslated region of the NKG2D gene and microRNA as well as their functional roles in the regulation of NKG2D expression and cytotoxicity in natural killer cells. Results Transforming growth factor-β1, a major negative regulator of NKG2D expression, post-transcriptionally up-regulated mature microRNA-1245 expression, thus down-regulating NKG2D expression and impairing NKG2D-mediated immune responses in natural killer cells. Conversely, microRNA-1245 down-regulation significantly increased the expression of NKG2D expression in natural killer cells, resulting in more efficient NKG2D-mediated cytotoxicity. Conclusions These results reveal a novel NKG2D regulatory pathway mediated by microRNA-1245, which may represent one of the mechanisms used by transforming growth factor-β1 to attenuate NKG2D expression in natural killer cells. PMID:22491735
Tubby, Carolyn; Negm, Ola H; Harrison, Timothy; Tighe, Patrick J; Todd, Ian; Fairclough, Lucy C
2017-06-01
The three main types of killer cells - CD8 + T cells, NK cells and NKT cells - have been linked to asthma and chronic obstructive pulmonary disease (COPD). However, their role in a small subset of asthma patients displaying fixed airway obstruction (FAO), similar to that seen in COPD, has not been explored. The objective of the present study was to investigate killer cell numbers, phenotype and function in peripheral blood from asthma patients with FAO, asthma patients without FAO, and healthy individuals. Peripheral CD8 + T cells (CD8 + CD3 + CD56 - ), NK cells (CD56 + CD3 - ) and NKT-like cells (CD56 + CD3 + ) of 14 asthma patients with FAO (post-bronchodilator FEV/FVC <0.7, despite clinician-optimised treatment), 7 asthma patients without FAO (post-bronchodilator FEV/FVC ≥ 0.7), and 9 healthy individuals were studied. No significant differences were seen between the number, receptor expression, MAPK signalling molecule expression, cytotoxic mediator expression, and functional cytotoxicity of peripheral killer cells from asthma patients with FAO, asthma patients without FAO and healthy individuals. Peripheral killer cell numbers or functions do not differentiate between asthma patients with or without fixed airway obstruction.
Liu, Wenhua; Gao, Yang; Li, Haibo; Wang, Hongliang; Ye, Ming; Jiang, Guihua; Chen, Yongsheng; Liu, Yang; Kong, Junying; Liu, Wei; Sun, Meng; Hou, Meng; Yu, Kaijiang
2016-10-01
Transplantation of mesenchymal stromal cells is a promising strategy for treating sepsis. Natural killer cells are important in the development of sepsis, and their functions can be inhibited by mesenchymal stromal cells, we asked whether mesenchymal stromal cells exert their therapeutic effects through inhibiting the functions of natural killer cells in a septic mouse model generated with cecal ligation puncture method. Using co-cultures of cells, small interfering RNA, enzyme-linked immnuosorbent assays, fluorescence assays, western blotting, and pathological examination, we investigated the levels of inflammatory cytokines, proliferation of natural killer cells, inflammatory infiltration of important organs in mice, and activity of the Janus kinase/signal transducer and activator of transcription signaling pathway and found that mesenchymal stromal cells inhibited the function and proliferation of septic natural killer cells, increased interleukin-10 levels and increased the expression of components, such as Janus kinase 1, Janus kinase 2, and signal transducer and activator of transcription 3 in the Janus kinase/signal transducer and activator of transcription pathway both in vitro and in vivo. We conclude that mesenchymal stromal cells have their therapeutic effect in the septic mouse model through inhibiting the function and proliferation of septic natural killer cells. This biological process may involve interleukin-10 and suppressor of cytokine signaling 3 as well as other pathway components in the Janus kinase/signal transducer and activator of transcription pathway. Transplantation of mesenchymal stromal cells is an effective strategy to treat sepsis. Copyright © 2016. Published by Elsevier Ltd.
Jiang, Hong Ning; Li, Yuan; Jiang, Wen Yi; Cui, Zong Jie
2018-01-01
Plasma membrane-delimited generation of singlet oxygen by photodynamic action with photosensitizer sulfonated aluminum phthalocyanine (SALPC) activates cholecystokinin 1 receptor (CCK1R) in pancreatic acini. Whether CCK1R retains such photooxidative singlet oxygen activation properties in other environments is not known. Genetically encoded protein photosensitizers KillerRed or mini singlet oxygen generator (miniSOG) were expressed in pancreatic acinar tumor cell line AR4-2J, CCK1R, KillerRed or miniSOG were expressed in HEK293 or CHO-K1 cells. Cold light irradiation (87 mW⋅cm -2 ) was applied to photosensitizer-expressing cells to examine photodynamic activation of CCK1R by Fura-2 fluorescent calcium imaging. When CCK1R was transduced into HEK293 cells which lack endogenous CCK1R, photodynamic action with SALPC was found to activate CCK1R in CCK1R-HEK293 cells. When KillerRed or miniSOG were transduced into AR4-2J which expresses endogenous CCK1R, KillerRed or miniSOG photodynamic action at the plasma membrane also activated CCK1R. When fused KillerRed-CCK1R was transduced into CHO-K1 cells, light irradiation activated the fused CCK1R leading to calcium oscillations. Therefore KillerRed either expressed independently, or fused with CCK1R can both activate CCK1R photodynamically. It is concluded that photodynamic singlet oxygen activation is an intrinsic property of CCK1R, independent of photosensitizer used, or CCK1R-expressing cell types. Photodynamic singlet oxygen CCK1R activation after transduction of genetically encoded photosensitizer in situ may provide a convenient way to verify intrinsic physiological functions of CCK1R in multiple CCK1R-expressing cells and tissues, or to actuate CCK1R function in CCK1R-expressing and non-expressing cell types after transduction with fused KillerRed-CCK1R.
Deficient natural killer cell function in preeclampsia
DOE Office of Scientific and Technical Information (OSTI.GOV)
Alanen, A.; Lassila, O.
1982-11-01
Natural killer cell activity of peripheral blood lymphocytes was measured against K-562 target cells with a 4-hour /sup 51/Cr release assay in 15 primigravid women with preeclamptic symptoms. Nineteen primigravid women with an uncomplicated pregnancy and 18 nonpregnant women served as controls. The natural killer cell activity of preeclamptic women was observed to be significantly lower than that of both control groups. Natural killer cells in preeclamptic women responded normally to augmentation caused by interferon. These findings give further evidence for the participation of the maternal immune system in this pregnancy disorder.
Pittari, Gianfranco; Filippini, Perla; Gentilcore, Giusy; Grivel, Jean-Charles; Rutella, Sergio
2015-01-01
Natural killer (NK) cells belong to innate immunity and exhibit cytolytic activity against infectious pathogens and tumor cells. NK-cell function is finely tuned by receptors that transduce inhibitory or activating signals, such as killer immunoglobulin-like receptors, NK Group 2 member D (NKG2D), NKG2A/CD94, NKp46, and others, and recognize both foreign and self-antigens expressed by NK-susceptible targets. Recent insights into NK-cell developmental intermediates have translated into a more accurate definition of culture conditions for the in vitro generation and propagation of human NK cells. In this respect, interleukin (IL)-15 and IL-21 are instrumental in driving NK-cell differentiation and maturation, and hold great promise for the design of optimal NK-cell culture protocols. Cytokine-induced killer (CIK) cells possess phenotypic and functional hallmarks of both T cells and NK cells. Similar to T cells, they express CD3 and are expandable in culture, while not requiring functional priming for in vivo activity, like NK cells. CIK cells may offer some advantages over other cell therapy products, including ease of in vitro propagation and no need for exogenous administration of IL-2 for in vivo priming. NK cells and CIK cells can be expanded using a variety of clinical-grade approaches, before their infusion into patients with cancer. Herein, we discuss GMP-compliant strategies to isolate and expand human NK and CIK cells for immunotherapy purposes, focusing on clinical trials of adoptive transfer to patients with hematological malignancies.
USDA-ARS?s Scientific Manuscript database
Natural killer (NK) cells are a diverse population of lymphocytes with a range of biological roles including essential immune functions. NK cell diversity is created by the differential expression of cell surface receptors which modulate activation and function, including multiple subfamilies of C-t...
Solaymani-Mohammadi, Shahram; Lakhdari, Omar; Minev, Ivelina; Shenouda, Steve; Frey, Blake F; Billeskov, Rolf; Singer, Steven M; Berzofsky, Jay A; Eckmann, Lars; Kagnoff, Martin F
2016-03-01
The programmed death-1 receptor is expressed on a wide range of immune effector cells, including T cells, natural killer T cells, dendritic cells, macrophages, and natural killer cells. In malignancies and chronic viral infections, increased expression of programmed death-1 by T cells is generally associated with a poor prognosis. However, its role in early host microbial defense at the intestinal mucosa is not well understood. We report that programmed death-1 expression is increased on conventional natural killer cells but not on CD4(+), CD8(+) or natural killer T cells, or CD11b(+) or CD11c(+) macrophages or dendritic cells after infection with the mouse pathogen Citrobacter rodentium. Mice genetically deficient in programmed death-1 or treated with anti-programmed death-1 antibody were more susceptible to acute enteric and systemic infection with Citrobacter rodentium. Wild-type but not programmed death-1-deficient mice infected with Citrobacter rodentium showed significantly increased expression of the conventional mucosal NK cell effector molecules granzyme B and perforin. In contrast, natural killer cells from programmed death-1-deficient mice had impaired expression of those mediators. Consistent with programmed death-1 being important for intracellular expression of natural killer cell effector molecules, mice depleted of natural killer cells and perforin-deficient mice manifested increased susceptibility to acute enteric infection with Citrobacter rodentium. Our findings suggest that increased programmed death-1 signaling pathway expression by conventional natural killer cells promotes host protection at the intestinal mucosa during acute infection with a bacterial gut pathogen by enhancing the expression and production of important effectors of natural killer cell function. © Society for Leukocyte Biology.
Effect of spaceflight on natural killer cell activity
NASA Technical Reports Server (NTRS)
Rykova, Marina P.; Sonnenfeld, Gerald; Lesniak, A. T.; Taylor, Gerald R.; Meshkov, Dimitrii O.; Mandel, Adrian D.; Medvedev, Andrei E.; Berry, Wallace D.; Fuchs, Boris B.; Konstantinova, Irina V.
1992-01-01
The effects of spaceflight on immune cell function were determined in rats flown on Cosmos 2044. Control groups included vivarium, synchronous, and antiorthostatically suspended rats. The ability of natural killer cells to lyse two different target cell lines was determined. Spleen and bone marrow cells obtained from flight rats showed significantly inhibited cytotoxicity for YAC-1 target cells compared with cells from synchronous control rats. This could have been due to exposure of the rats to microgravity. Antiorthostatic suspension did not affect the level of cytotoxicity from spleen cells of suspended rats for YAC-1 cells. On the other hand, cells from rats flown in space showed no significant differences from vivarium and synchronous control rats in cytotoxicity for K-562 target cells. Binding of natural killer cells to K-562 target cells was unaffected by spaceflight. Antiorthostatic suspension resulted in higher levels of cytotoxicity from spleen cells for Cr-51-labeled K-562 cells. The results indicate differential effects of spaceflight on function of natural killer cells. This shows that spaceflight has selective effects on the immune response.
Lidocaine Stimulates the Function of Natural Killer Cells in Different Experimental Settings.
Cata, Juan P; Ramirez, Maria F; Velasquez, Jose F; Di, A I; Popat, Keyuri U; Gottumukkala, Vijaya; Black, Dahlia M; Lewis, Valerae O; Vauthey, Jean N
2017-09-01
One of the functions of natural killer (NK) cells is to eliminate cancer cells. The cytolytic activity of NK cells is tightly regulated by inhibitory and activation receptors located in the surface membrane. Lidocaine stimulates the function of NK cells at clinically relevant concentrations. It remains unknown whether this effect of lidocaine has an impact on the expression of surface receptors of NK cells, can uniformly stimulate across different cancer cell lines, and enhances the function of cells obtained during oncological surgery. NK cells from healthy donors and 43 patients who had undergone surgery for cancer were isolated. The function of NK cells was measured by lactate dehydrogenase release assay. NK cells were incubated with clinically relevant concentrations of lidocaine. By flow cytometry, we determined the impact of lidocaine on the expression of galactosylgalactosylxylosylprotein3-beta-glucuronosytranferase 1, marker of cell maturation (CD57), killer cell lectin like receptor A, inhibitory (NKG2A) receptors and killer cell lectin like receptor D, activation (NKG2D) receptors of NK cells. Differences in expression at p<0.05 were considered statistically significant. Lidocaine increased the expression of NKG2D receptors and stimulated the function of NK cells against ovarian, pancreatic and ovarian cancer cell lines. Lidocaine also increased the cytolytic activity of NK cells from patients who underwent oncological surgery, except for those who had orthopedic procedures. Lidocaine showed an important stimulatory activity on NK cells. Our findings suggest that lidocaine might be used perioperatively to minimize the impact of surgery on NK cells. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.
Roberto, Alessandra; Di Vito, Clara; Zaghi, Elisa; Mazza, Emilia Maria Cristina; Capucetti, Arianna; Calvi, Michela; Tentorio, Paolo; Zanon, Veronica; Sarina, Barbara; Mariotti, Jacopo; Bramanti, Stefania; Tenedini, Elena; Tagliafico, Enrico; Bicciato, Silvio; Santoro, Armando; Roederer, Mario; Marcenaro, Emanuela; Castagna, Luca; Lugli, Enrico; Mavilio, Domenico
2018-04-26
Natural Killer cells are the first lymphocyte population to reconstitute early after non myelo-ablative and T cell-replete haploidentical hematopoietic stem cell transplantation with post-transplant infusion of cyclophosphamide. The present study characterizes the transient and predominant expansion starting from the 2nd week after haploidentical hematopoietic stem cell transplantation of a donor-derived unconventional subset of NKp46neg-low/CD56dim/CD16neg natural killer cells expressing remarkable high levels of CD94/NKG2A. Both transcription and phenotypic profiles indicated that unconventional NKp46neg-low/CD56dim/CD16neg natural killer cells are a distinct natural killer cell subpopulation with features of late stage differentiation, yet retaining proliferative capability and functional plasticity to generate conventional NKp46pos/CD56bright/CD16pos natural killer cells in response to interleukin-15 plus interleukin-18. While present at low frequency in healthy donors, unconventional NKp46neg-low/CD56dim/CD16neg natural killer cells are greatly expanded in the following 7 weeks after haploidentical hematopoietic stem cell transplantation and express high levels of the activating receptors NKGD and NKp30 as well as of the lytic granules Granzyme-B and Perforin. Nonetheless, NKp46neg-low/CD56dim/CD16neg natural killer cells displayed a markedly defective cytotoxicity that could be reversed by blocking the inhibitory receptor CD94/NKG2A. These data open new important perspectives to better understand the ontogenesis/homeostasis of human natural killer cells and to develop a novel immune-therapeutic approach that targets the inhibitory NKG2A check point, thus unleashing natural killer cell alloreactivity early after haploidentical hematopoietic stem cell transplantation. Copyright © 2018, Ferrata Storti Foundation.
The Human Natural Killer Cell Immune Synapse
NASA Astrophysics Data System (ADS)
Davis, Daniel M.; Chiu, Isaac; Fassett, Marlys; Cohen, George B.; Mandelboim, Ofer; Strominger, Jack L.
1999-12-01
Inhibitory killer Ig-like receptors (KIR) at the surface of natural killer (NK) cells induced clustering of HLA-C at the contacting surface of target cells. In this manner, inhibitory immune synapses were formed as human NK cells surveyed target cells. At target/NK cell synapses, HLA-C/KIR distributed into rings around central patches of intercellular adhesion molecule-1/lymphocyte function-associated antigen-1, the opposite orientation to mature murine T cell-activating synapses. This organization of protein was stable for at least 20 min. Cells could support multiple synapses simultaneously, and clusters of HLA-C moved as NK cells crawled over target cells. Clustering required a divalent metal cation, explaining how metal chelators inhibit KIR function. Surprisingly, however, formation of inhibitory synapses was unaffected by ATP depletion and the cytoskeletal inhibitors, colchicine and cytochalsins B and D. Clearly, supramolecular organization within plasma membranes is critical for NK cell immunosurveillance.
Malova, E S; Balmasova, I P; Iuschuk, N D; Shmeleva, E V; Eremina, O F
2010-01-01
To study functional activity of natural killers on different stages of fibrosis during chronic hepatitis C. Functional activity of CD3-/CD56+/CD16+ lymphocytes measured as expression of natural killers receptors (NKR) and natural cytotoxicity receptors (NCR) was assessed by flow cytometry. At stage I of fibrosis, decrease of number of CD3-/CD56+/NKG2D+ cells was observed, whereas at precirrhotic stage III--sharp decrease of CD3-/CD56+/CD94+ and CD3-/ CD56+/NKG2D+ populations, and at cirrhotic stage--decrease of number of CD3-/CD56+/ NKG2D+ cells and increase of cytolytic activity of natural killers carrying CD107a marker compared to precirrhotic stage. Obtained data demonstrate that natural killers during chronic hepatitis C receive regulatory signals mainly through lectin type receptors (CD94 and NKG2D).
Endogenous cannabinoid receptor ligand induces the migration of human natural killer cells.
Kishimoto, Seishi; Muramatsu, Mayumi; Gokoh, Maiko; Oka, Saori; Waku, Keizo; Sugiura, Takayuki
2005-02-01
2-Arachidonoylglycerol is an endogenous ligand for the cannabinoid receptors (CB1 and CB2). Evidence is gradually accumulating which shows that 2-arachidonoylglycerol plays important physiological roles in several mammalian tissues and cells, yet the details remain ambiguous. In this study, we first examined the effects of 2-arachidonoylglycerol on the motility of human natural killer cells. We found that 2-arachidonoylglycerol induces the migration of KHYG-1 cells (a natural killer leukemia cell line) and human peripheral blood natural killer cells. The migration of natural killer cells induced by 2-arachidonoylglycerol was abolished by treating the cells with SR144528, a CB2 receptor antagonist, suggesting that the CB2 receptor is involved in the 2-arachidonoylglycerol-induced migration. In contrast to 2-arachidonoylglycerol, anandamide, another endogenous cannabinoid receptor ligand, did not induce the migration. Delta9-tetrahydrocannabinol, a major psychoactive constituent of marijuana, also failed to induce the migration; instead, the addition of delta9-tetrahydrocannabinol together with 2-arachidonoylglycerol abolished the migration induced by 2-arachidonoylglycerol. It is conceivable that the endogenous ligand for the cannabinoid receptor, that is, 2-arachidonoylglycerol, affects natural killer cell functions such as migration, thereby contributing to the host-defense mechanism against infectious viruses and tumor cells.
View Point: Semaphorin-3E: An Emerging Modulator of Natural Killer Cell Functions?
Alamri, Abdulaziz; Soussi Gounni, Abdelilah; Kung, Sam K. P.
2017-01-01
Semaphorin-3E (Sema-3E) is a member of a large family of proteins originally identified as axon guidance cues in neural development. It is expressed in different cell types, such as immune cells, cancer cells, neural cells, and epithelial cells. Subsequently, dys-regulation of Sema-3E expression has been reported in various biological processes that range from cancers to autoimmune and allergic diseases. Recent work in our laboratories revealed a critical immunoregulatory role of Sema-3E in experimental allergic asthma. We further speculate possible immune modulatory function(s) of Sema-3E on natural killer (NK) cells. PMID:29113093
Roquilly, Antoine; Broquet, Alexis; Jacqueline, Cédric; Masson, Damien; Segain, Jean Pierre; Braudeau, Cecile; Vourc'h, Mickael; Caillon, Jocelyne; Altare, Frédéric; Josien, Regis; Retière, Christelle; Villadangos, Jose; Asehnoune, Karim
2014-12-01
Trauma induces a state of immunosuppression, which is responsible for the development of nosocomial infections. Hydrocortisone reduces the rate of pneumonia in patients with trauma. Because alterations of dendritic cells and natural killer cells play a central role in trauma-induced immunosuppression, we investigated whether hydrocortisone modulates the dendritic cell/natural killer cell cross talk in the context of posttraumatic pneumonia. Experimental study. Research laboratory from an university hospital. Bagg Albino/cJ mice (weight, 20-24 g). First, in an a priori substudy of a multicenter, randomized, double-blind, placebo-controlled trial of hydrocortisone (200 mg/d for 7 d) in patients with severe trauma, we have measured the blood levels of five cytokines (tumor necrosis factor-α, interleukin-6, interleukin-10, interleukin-12, interleukin-17) at day 1 and day 8. In a second step, the effects of hydrocortisone on dendritic cell/natural killer cell cross talk were studied in a mouse model of posttraumatic pneumonia. Hydrocortisone (0.6 mg/mice i.p.) was administered immediately after hemorrhage. Twenty-four hours later, the mice were challenged with Staphylococcus aureus (7 × 10 colony-forming units). Using sera collected during a multicenter study in patients with trauma, we found that hydrocortisone decreased the blood level of interleukin-10, a cytokine centrally involved in the regulation of dendritic cell/natural killer cell cluster. In a mouse model of trauma-hemorrhage-induced immunosuppression, splenic natural killer cells induced an interleukin-10-dependent elimination of splenic dendritic cell. Hydrocortisone treatment reduced this suppressive function of natural killer cells and increased survival of mice with posthemorrhage pneumonia. The reduction of the interleukin-10 level in natural killer cells by hydrocortisone was partially dependent on the up-regulation of glucocorticoid-induced tumor necrosis factor receptor-ligand (TNFsf18) on dendritic cell. These data demonstrate that trauma-induced immunosuppression is characterized by an interleukin-10-dependent elimination of dendritic cell by natural killer cells and that hydrocortisone improves outcome by limiting this immunosuppressive feedback loop.
Bollino, Dominique; Webb, Tonya J
2017-09-01
Natural killer (NK) cells of the innate immune system and natural killer T (NKT) cells, which have roles in both the innate and adaptive responses, are unique lymphocyte subsets that have similarities in their functions and phenotypes. Both cell types can rapidly respond to the presence of tumor cells and participate in immune surveillance and antitumor immune responses. This has incited interest in the development of novel cancer therapeutics based on NK and NKT cell manipulation. Chimeric antigen receptors (CARs), generated through the fusion of an antigen-binding region of a monoclonal antibody or other ligand to intracellular signaling domains, can enhance lymphocyte targeting and activation toward diverse malignancies. Most of the CAR studies have focused on their expression in T cells; however, the functional heterogeneity of CAR T cells limits their therapeutic potential and is associated with toxicity. CAR-modified NK and NKT cells are becoming more prevalent because they provide a method to direct these cells more specifically to target cancer cells, with less risk of adverse effects. This review will outline current NK and NKT cell CAR constructs and how they compare to conventional CAR T cells, and discuss future modifications that can be explored to advance adoptive cell transfer of NK and NKT cells. Copyright © 2017 Elsevier Inc. All rights reserved.
Restoration of Immune Surveillance in Lung Cancer by Natural Killer Cells
2016-10-01
and had no dramatic effects on NK cell, unlike TGFb, although this product had been effective in the past. However, the pathway that Nicotine and... effects of nicotine on NK function in vivo in smokers and have proceeded to conduct the clinical protocol in Aim 2. Aim 2. To verify that use of...molecule, DAP12, that controls tumoricidal function in human Natural Killer (NK) Cells and to understand how nicotine , contained in tobacco smoke
Natural killer T cells in health and disease
Wu, Lan; Van Kaer, Luc
2013-01-01
Natural killer T (NKT) cells are a subset of T lymphocytes that share surface markers and functional characteristics with both conventional T lymphocytes and natural killer cells. Most NKT cells express a semiinvariant T cell receptor that reacts with glycolipid antigens presented by the major histocompatibility complex class I-related protein CD1d on the surface of antigen-presenting cells. NKT cells become activated during a variety of infections and inflammatory conditions, rapidly producing large amounts of immunomodulatory cytokines. NKT cells can influence the activation state and functional properties of multiple other cell types in the immune system and, thus, modulate immune responses against infectious agents, autoantigens, tumors, tissue grafts and allergens. One attractive aspect of NKT cells is that their immunomodulatory activities can be readily harnessed with cognate glycolipid antigens, such as the marine sponge-derived glycosphingolipid alpha-galactosylceramide. These properties of NKT cells are being exploited for therapeutic intervention to prevent or treat cancer, infections, and autoimmune and inflammatory diseases. PMID:21196373
Decreased non-MHC-restricted (CD56+) killer cell cytotoxicity after spaceflight
NASA Technical Reports Server (NTRS)
Mehta, S. K.; Kaur, I.; Grimm, E. A.; Smid, C.; Feeback, D. L.; Pierson, D. L.
2001-01-01
Cytotoxic activity of non-major histocompatibility complex-restricted (CD56+) (NMHC) killer cells and cell surface marker expression of peripheral blood mononuclear cells were determined before and after spaceflight. Ten astronauts (9 men, 1 woman) from two space shuttle missions (9- and 10-day duration) participated in the study. Blood samples were collected 10 days before launch, within 3 h after landing, and 3 days after landing. All peripheral blood mononuclear cell preparations were cryopreserved and analyzed simultaneously in a 4-h cytotoxicity (51)Cr release assay using K562 target cells. NMHC killer cell lytic activity was normalized per 1,000 CD56+ cells. When all 10 subjects were considered as one study group, NMHC killer cell numbers did not change significantly during the three sampling periods, but at landing lytic activity had decreased by approximately 40% (P < 0.05) from preflight values. Nine of ten astronauts had decreased lytic activity immediately after flight. NMHC killer cell cytotoxicity of only three astronauts returned toward preflight values by 3 days after landing. Consistent with decreased NMHC killer cell cytotoxicity, urinary cortisol significantly increased after landing compared with preflight levels. Plasma cortisol and ACTH levels at landing were not significantly different from preflight values. No correlation of changes in NMHC killer cell function or hormone levels with factors such as age, gender, mission, or spaceflight experience was found. After landing, expression of the major lymphocyte surface markers (CD3, CD4, CD8, CD14, CD16, CD56), as determined by flow cytometric analysis, did not show any consistent changes from measurements made before flight.
Nabatanzi, Rose; Cose, Stephen; Joloba, Moses; Jones, Sarah Rowland; Nakanjako, Damalie
2018-03-15
HIV infection causes upregulation of markers of inflammation, immune activation and apoptosis of host adaptive, and innate immune cells particularly monocytes, natural killer (NK) and innate lymphoid cells (ILCs). Although antiretroviral therapy (ART) restores CD4 T-cell counts, the persistent aberrant activation of monocytes, NK and ILCs observed likely contributes to the incomplete recovery of T-cell effector functions. A better understanding of the effects of HIV infection and ART on the phenotype and function of circulating monocytes, NK, and ILCs is required to guide development of novel therapeutic interventions to optimize immune recovery.
Powell, Jeralyn J.; Davis, McLisa V.; Whalen, Margaret M.
2008-01-01
This study investigated whether reduced glutathione (GSH) was able to alter the negative effects of tributyltin (TBT) or dibutyltin (DBT) on the lytic function of human natural killer (NK) cells. NK cells are an intital immune defense against the development of tumors or viral infections. TBT and DBT are widespread environmental contaminants, due to their various industrial applications. Both TBT and DBT have been shown to decrease the ability of NK cells to lyse tumor cells (lytic function). The results indicated that the presence of GSH during exposure of NK cells to TBT or DBT diminished the negative effect of the BT on the lytic function of NK cells. This suggests that interaction TBT and DBT with functionally relevant sulfhydryl groups in NK cells may be part of the mechanism by which they decrease NK lytic function. PMID:18821099
Powell, Jeralyn J; Davis, McLisa V; Whalen, Margaret M
2009-01-01
This study investigated whether reduced glutathione (GSH) was able to alter the negative effects of tributyltin (TBT) or dibutyltin (DBT) on the lytic function of human natural killer (NK) cells. NK cells are an initial immune defense against the development of tumors or viral infections. TBT and DBT are widespread environmental contaminants, due to their various industrial applications. Both TBT and DBT have been shown to decrease the ability of NK cells to lyse tumor cells (lytic function). The results indicated that the presence of GSH during the exposure of NK cells to TBT or DBT diminished the negative effect of the butyltin on the lytic function of NK cells. This suggests that the interaction of TBT and DBT with functionally relevant sulfhydryl groups in NK cells may be part of the mechanism by which they decrease NK lytic function.
Epstein–Barr virus-positive T/NK-cell lymphoproliferative disorders
Cai, Qingqing; Chen, Kailin; Young, Ken H
2015-01-01
Epstein–Barr virus, a ubiquitous human herpesvirus, can induce both lytic and latent infections that result in a variety of human diseases, including lymphoproliferative disorders. The oncogenic potential of Epstein–Barr virus is related to its ability to infect and transform B lymphocytes into continuously proliferating lymphoblastoid cells. However, Epstein–Barr virus has also been implicated in the development of T/natural killer cell lymphoproliferative diseases. Epstein–Barr virus encodes a series of products that mimic several growth, transcription and anti-apoptotic factors, thus usurping control of pathways that regulate diverse homeostatic cellular functions and the microenvironment. However, the exact mechanism by which Epstein–Barr virus promotes oncogenesis and inflammatory lesion development remains unclear. Epstein–Barr virus-associated T/natural killer cell lymphoproliferative diseases often have overlapping clinical symptoms as well as histologic and immunophenotypic features because both lymphoid cell types derive from a common precursor. Accurate classification of Epstein–Barr virus-associated T/natural killer cell lymphoproliferative diseases is a prerequisite for appropriate clinical management. Currently, the treatment of most T/natural killer cell lymphoproliferative diseases is less than satisfactory. Novel and targeted therapies are strongly required to satisfy clinical demands. This review describes our current knowledge of the genetics, oncogenesis, biology, diagnosis and treatment of Epstein–Barr virus-associated T/natural killer cell lymphoproliferative diseases. PMID:25613730
Cooper, Megan A; Fehniger, Todd A; Colonna, Marco
2017-12-18
Studies over the last decade have decisively shown that innate immune natural killer (NK) cells exhibit enhanced long-lasting functional responses following a single activation event. With the increased recognition of memory and memory-like properties of NK cells, questions have arisen with regard to their ability to effectively mediate vaccination responses in humans. Moreover, recently discovered innate lymphoid cells (ILCs) could also potentially exhibit memory-like functions. Here, we review different forms of NK cell memory, and speculate about the ability of these cells and ILCs to meaningfully contribute to vaccination responses. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.
Kuśnierczyk, Piotr
2013-01-01
Killer cell immunoglobulin-like receptors (KIRs) are a family of cell surface inhibitory or activating receptors expressed on natural killer cells and some subpopulations of T lymphocytes. KIR genes are clustered in the 19q13.4 region and are characterized by both allelic (high numbers of variants) and haplotypic (different numbers of genes for inhibitory and activating receptors on individual chromosomes) polymorphism. This contributes to diverse susceptibility to diseases and other clinical situations. Associations of KIR genes, as well as of genes for their ligands, with selected diseases such as psoriasis vulgaris and atopic dermatitis, rheumatoid arthritis, recurrent spontaneous abortion, and non-small cell lung cancer are discussed in the context of NK and T cell functions. PMID:23372569
Gaoatswe, Gadintshware; Kent, Brian D; Corrigan, Michelle A; Nolan, Geraldine; Hogan, Andrew E; McNicholas, Walter T; O'Shea, Donal
2015-10-01
Emerging evidence links obstructive sleep apnea (OSA) with increased cancer incidence and mortality. Invariant natural killer T (iNKT) cells play an important role in cancer immunity. We hypothesized that patients with OSA have low number of circulating invariant natural killer T (iNKT) cells, which may also be functionally impaired. This study aims to evaluate the frequency of circulating iNKT cells in OSA. We evaluated the frequency of circulating iNKT cells by flow cytometry in 33 snorers being assessed for possible OSA. Using iNKT cell lines, we also evaluated the effect of exposure to hypoxia over 24 hours on apoptosis, cytotoxicity, and cytokine production. Teaching hospital based sleep unit and research laboratory. Thirty-three snorers were evaluated: 9 with no OSA (apnea-hypopnea frequency [AHI] < 5/h), 12 with mild-moderate OSA (AHI 5-30) and 12 with severe OSA (AHI > 30). Patients with severe OSA had considerably fewer iNKT cells (0.18%) compared to patients with mild-moderate (0.24%) or no OSA (0.35%), P = 0.0026. The frequency of iNKT cells correlated negatively with apnea-hypopnea index (r = -0.58, P = 0.001), oxygen desaturation index (r = -0.58, P = 0.0003), and SpO2% < 90% (r = -0.5407, P = 0.005). The frequency of iNKT cells increased following 12 months of nCPAP therapy (P = 0.015). Hypoxia resulted in increased apoptosis (P = 0.016) and impaired cytotoxicity (P = 0.035). Patients with obstructive sleep apnea (OSA) have significantly reduced levels of circulating invariant natural killer T (iNKT) cells and hypoxia leads to impaired iNKT cell function. These observations may partly explain the increased cancer risk reported in patients with OSA. © 2015 Associated Professional Sleep Societies, LLC.
A novel system of polymorphic and diverse NK cell receptors in primates.
Averdam, Anne; Petersen, Beatrix; Rosner, Cornelia; Neff, Jennifer; Roos, Christian; Eberle, Manfred; Aujard, Fabienne; Münch, Claudia; Schempp, Werner; Carrington, Mary; Shiina, Takashi; Inoko, Hidetoshi; Knaust, Florian; Coggill, Penny; Sehra, Harminder; Beck, Stephan; Abi-Rached, Laurent; Reinhardt, Richard; Walter, Lutz
2009-10-01
There are two main classes of natural killer (NK) cell receptors in mammals, the killer cell immunoglobulin-like receptors (KIR) and the structurally unrelated killer cell lectin-like receptors (KLR). While KIR represent the most diverse group of NK receptors in all primates studied to date, including humans, apes, and Old and New World monkeys, KLR represent the functional equivalent in rodents. Here, we report a first digression from this rule in lemurs, where the KLR (CD94/NKG2) rather than KIR constitute the most diverse group of NK cell receptors. We demonstrate that natural selection contributed to such diversification in lemurs and particularly targeted KLR residues interacting with the peptide presented by MHC class I ligands. We further show that lemurs lack a strict ortholog or functional equivalent of MHC-E, the ligands of non-polymorphic KLR in "higher" primates. Our data support the existence of a hitherto unknown system of polymorphic and diverse NK cell receptors in primates and of combinatorial diversity as a novel mechanism to increase NK cell receptor repertoire.
A Novel System of Polymorphic and Diverse NK Cell Receptors in Primates
Rosner, Cornelia; Neff, Jennifer; Roos, Christian; Eberle, Manfred; Aujard, Fabienne; Münch, Claudia; Schempp, Werner; Carrington, Mary; Shiina, Takashi; Inoko, Hidetoshi; Knaust, Florian; Coggill, Penny; Sehra, Harminder; Beck, Stephan; Abi-Rached, Laurent; Reinhardt, Richard; Walter, Lutz
2009-01-01
There are two main classes of natural killer (NK) cell receptors in mammals, the killer cell immunoglobulin-like receptors (KIR) and the structurally unrelated killer cell lectin-like receptors (KLR). While KIR represent the most diverse group of NK receptors in all primates studied to date, including humans, apes, and Old and New World monkeys, KLR represent the functional equivalent in rodents. Here, we report a first digression from this rule in lemurs, where the KLR (CD94/NKG2) rather than KIR constitute the most diverse group of NK cell receptors. We demonstrate that natural selection contributed to such diversification in lemurs and particularly targeted KLR residues interacting with the peptide presented by MHC class I ligands. We further show that lemurs lack a strict ortholog or functional equivalent of MHC-E, the ligands of non-polymorphic KLR in “higher” primates. Our data support the existence of a hitherto unknown system of polymorphic and diverse NK cell receptors in primates and of combinatorial diversity as a novel mechanism to increase NK cell receptor repertoire. PMID:19834558
Zulu, Michael Z; Naidoo, Kewreshini K; Mncube, Zenele; Jaggernath, Manjeetha; Goulder, Philip J R; Ndung'u, Thumbi; Altfeld, Marcus; Thobakgale, Christina F
2017-12-01
HIV-1 viremia has been shown to induce several phenotypic and functional abnormalities in natural killer (NK) cells. To assess immune defects associated with HIV viremia, we examined NK cell function, differentiation status, and phenotypic alterations based on expression of inhibitory and activating receptors on NK cells in HIV-1 subtype C chronically infected participants from Durban, South Africa. NK cell phenotypic profiles were characterized by assessing sialic acid-binding immunoglobulin-like lectin-7 (Siglec-7), NKG2A, and NKG2C markers on frozen peripheral blood mononuclear cells from viremic, antiretroviral therapy (ART)-naive HIV-1 chronically infected participants (n = 23), HIV-1 chronically infected participants who had been on combination antiretroviral therapy (cART) for at least 12 months (n = 23) compared with healthy donors (n = 23). NK cell differentiation was assessed by measurement of killer immunoglobulin receptor (KIR) and NKG2A expression; CD57 and CD107a measurements were carried out in HIV viremic and healthy donors. All phenotypic and functional assessments were analyzed by using multicolor flow cytometry. HIV-1-infected participants displayed greater frequencies of the CD56 - CD16 + (CD56negative) NK cell subset compared with healthy donors (p < .0001). Downregulation of Siglec-7 and NKG2A and upregulation of NKG2C were more pronounced in the CD56negative NK cell subset of viremic participants. The CD56negative subset demonstrated a differentiated (KIR + NKG2A - ) phenotype with reduced CD57 expression and lower degranulation capacity in HIV-1-infected participants compared with healthy donors. HIV-1 infection induces the expansion of the CD56negative NK cell subset marked by altered receptor expression profiles that are indicative of impaired function and may explain the overall NK cell dysfunction observed in chronic HIV-1 infection.
López-Karpovitch, Xavier; Graue, Gerardo; Crespo-Solís, Erick; Piedras, Josefa
2008-07-01
High P-glycoprotein-mediated multidrug resistance-1 (P-gp/MDR1) activity in lymphocytes from idiopathic thrombocytopenic purpura (ITP) patients may affect disease outcome. ITP treatment includes glucocorticoids that are substrates of P-gp; hence, P-gp functional activity and antigenic expression were assessed by flow cytometry in T and natural killer (NK) cells from ITP patients before and after prednisone therapy. Herein, patients' T and NK cells did not show increased MDR1 functional activity, whereas P-gp antigenic expression was significantly enhanced in both therapy-free and prednisone-treated patients. Prednisone treatment did not significantly modify the function and expression of MDR1 in T and NK cells of ITP patients.
Natural Killer T Cells in Cancer Immunotherapy
Nair, Shiny; Dhodapkar, Madhav V.
2017-01-01
Natural killer T (NKT) cells are specialized CD1d-restricted T cells that recognize lipid antigens. Following stimulation, NKT cells lead to downstream activation of both innate and adaptive immune cells in the tumor microenvironment. This has impelled the development of NKT cell-targeted immunotherapies for treating cancer. In this review, we provide a brief overview of the stimulatory and regulatory functions of NKT cells in tumor immunity as well as highlight preclinical and clinical studies based on NKT cells. Finally, we discuss future perspectives to better harness the potential of NKT cells for cancer therapy. PMID:29018445
Synergistic inhibition of natural killer cells by the nonsignaling molecule CD94.
Cheent, Kuldeep S; Jamil, Khaleel M; Cassidy, Sorcha; Liu, Mengya; Mbiribindi, Berenice; Mulder, Arend; Claas, Frans H J; Purbhoo, Marco A; Khakoo, Salim I
2013-10-15
Peptide selectivity is a feature of inhibitory receptors for MHC class I expressed by natural killer (NK) cells. CD94-NKG2A operates in tandem with the polymorphic killer cell Ig-like receptors (KIR) and Ly49 systems to inhibit NK cells. However, the benefits of having two distinct inhibitory receptor-ligand systems are not clear. We show that noninhibitory peptides presented by HLA-E can augment the inhibition of NKG2A(+) NK cells mediated by MHC class I signal peptides through the engagement of CD94 without a signaling partner. Thus, CD94 is a peptide-selective NK cell receptor, and NK cells can be regulated by nonsignaling interactions. We also show that KIR(+) and NKG2A(+) NK cells respond with differing stoichiometries to MHC class I down-regulation. MHC-I-bound peptide functions as a molecular rheostat controlling NK cell function. Selected peptides which in isolation do not inhibit NK cells can have different effects on KIR and NKG2A receptors. Thus, these two inhibitory systems may complement each other by having distinct responses to bound peptide and surface levels of MHC class I.
Synergistic inhibition of natural killer cells by the nonsignaling molecule CD94
Cheent, Kuldeep S.; Jamil, Khaleel M.; Cassidy, Sorcha; Liu, Mengya; Mbiribindi, Berenice; Mulder, Arend; Claas, Frans H. J.; Purbhoo, Marco A.; Khakoo, Salim I.
2013-01-01
Peptide selectivity is a feature of inhibitory receptors for MHC class I expressed by natural killer (NK) cells. CD94–NKG2A operates in tandem with the polymorphic killer cell Ig-like receptors (KIR) and Ly49 systems to inhibit NK cells. However, the benefits of having two distinct inhibitory receptor–ligand systems are not clear. We show that noninhibitory peptides presented by HLA-E can augment the inhibition of NKG2A+ NK cells mediated by MHC class I signal peptides through the engagement of CD94 without a signaling partner. Thus, CD94 is a peptide-selective NK cell receptor, and NK cells can be regulated by nonsignaling interactions. We also show that KIR+ and NKG2A+ NK cells respond with differing stoichiometries to MHC class I down-regulation. MHC-I–bound peptide functions as a molecular rheostat controlling NK cell function. Selected peptides which in isolation do not inhibit NK cells can have different effects on KIR and NKG2A receptors. Thus, these two inhibitory systems may complement each other by having distinct responses to bound peptide and surface levels of MHC class I. PMID:24082146
van Rensburg, Ilana C; Loxton, Andre G
2018-01-01
Regulatory B cells (Bregs) have been shown to be present during several disease states. The phenotype of the cells is not completely defined and the function of these cells differ between disease. The presence of FASL expressing (killer) B cells during latent and successfully treated TB disease have been shown but whether these cells are similar to regulatory B cells remain unclear. We assessed the receptor expression of FASL/IL5 (killer B cells), CD24/CD38 (regulatory B cells) on whole peripheral blood of participants with untreated active TB and healthy controls. We then isolated B cells from a second cohort of M.tb exposed (Quantiferon (QFN) positive) and unexposed (Quantiferon negative) HIV negative participants, and evaluated the frequency of killer B cells induced following stimulation with BCG and/or CD40 and IL5. Our data reveal no difference in the expression on CD24 and CD38 between participants with active TB and the controls. There was also no difference in the frequency of regulatory B cells measured in the peripheral blood mononuclear cells (PBMC) fraction between latent TB and uninfected controls. We did however notice that regulatory B cells (CD24hiCD38hi) population express the FASL receptor. The expression of killer B cell phenotype (CD178+IL5RA+) was significantly higher in controls compared to those with active TB disease (1,06% vs 0,455%). Furthermore, we found that BCG restimulation significantly induced the FASL/IL5RA B cells but this was only evident in the QFN positive group. Our data suggest that both regulatory and killer B cells are present during latent and active TB disease but that the frequency of these populations are increased during latent disease. We also show that the FASL+IL5RA+ B killer B cells are induced in latent TB infection following BCG restimulation but whether these cells are indicative of protection remains unclear. Copyright © 2017 Elsevier Ltd. All rights reserved.
Desforges, Jean-Pierre; Jasperse, Lindsay; Jensen, Trine Hammer; Grøndahl, Carsten; Bertelsen, Mads F; Guise, Sylvain De; Sonne, Christian; Dietz, Rune; Levin, Milton
2018-01-01
Natural killer (NK) cells are a vital part of the rapid and non-specific immune defense against invading pathogens and tumor cells. This study evaluated NK cell-like activity by flow cytometry for the first time in three ecologically and culturally important Arctic mammal species: polar bear (Ursus maritimus), muskox (Ovibos moschatus) and reindeer (Rangifer tarandus). NK cell-like activity for all three species was most effective against the mouse lymphoma cell line YAC-1, compared to the human leukemia cell line K562; NK cell response displayed the characteristic increase in cytotoxic activity when the effector:target cell ratio increased. Comparing NK activity between fresh and cryopreserved mouse lymphocytes revealed little to no difference in function, highlighting the applicability of cryopreserving cells in field studies. The evaluation of this important innate immune function in Arctic mammals can contribute to future population health assessments, especially as pollution-induced suppression of immune function may increase infectious disease susceptibility. Copyright © 2017 Elsevier B.V. All rights reserved.
Education of human natural killer cells by activating killer cell immunoglobulin-like receptors.
Fauriat, Cyril; Ivarsson, Martin A; Ljunggren, Hans-Gustaf; Malmberg, Karl-Johan; Michaëlsson, Jakob
2010-02-11
Expression of inhibitory killer cell immunoglobulin-like receptors (KIRs) specific for self-major histocompatibility complex (MHC) class I molecules provides an educational signal that generates functional natural killer (NK) cells. However, the effects of activating KIRs specific for self-MHC class I on NK-cell education remain elusive. Here, we provide evidence that the activating receptor KIR2DS1 tunes down the responsiveness of freshly isolated human NK cells to target cell stimulation in donors homozygous for human leukocyte antigen (HLA)-C2, the ligand of KIR2DS1. The tuning was apparent in KIR2DS1(+) NK cells lacking expression of inhibitory KIRs and CD94/NKG2A, as well as in KIR2DS1(+) NK cells coexpressing the inhibitory MHC class I-specific receptors CD94/NKG2A and KIR2DL3, but not KIR2DL1. However, the tuning of responsiveness was restricted to target cell recognition because KIR2DS1(+) NK cells responded well to stimulation with exogenous cytokines. Our results provide the first example of human NK-cell education by an activating KIR and suggest that the education of NK cells via activating KIRs is a mechanism to secure tolerance that complements education via inhibitory KIRs.
Relationship of aging and nutritional status to innate immunity in tube-fed bedridden patients.
Takeuchi, Yoshiaki; Tashiro, Tomoe; Yamamura, Takuya; Takahashi, Seiichiro; Katayose, Kozo; Kohga, Shin; Takase, Mitsunori; Imawari, Michio
2017-01-01
Aging and malnutrition are known to influence immune functions. The aim of this study was to investigate the relationship of aging and malnutrition to innate immune functions in tube-fed bedridden patients. A cross-sectional survey was performed in 71 tube-fed bedridden patients aged 50-95 years (mean age±SD, 80.2±8.5 years) with serum albumin concentrations between 2.5 and 3.5 g/dL. We evaluated associations of age and nutritional variables with natural-killer cell activity, neutrophilphagocytic activity, and neutrophil-sterilizing activity. Nutritional variables included body mass index, weightadjusted energy intake, total lymphocyte count, and serum concentrations of albumin, transferrin, prealbumin, total cholesterol, C-reactive protein, and zinc. Natural-killer cell activity, neutrophil-phagocytic activity, and neutrophil-sterilizing activity were normal or increased in 67 (94%), 63 (89%), and 69 (97%) patients, respectively. Multiple linear regression analysis with a backward elimination method showed that natural-killer cell activity correlated negatively with aging and lymphocyte counts (p<0.01 for both) but positively with body mass index and transferrin (p<0.01 for both). Neutrophil-phagocytic and neutrophil-sterilizing activities were not associated with any variables. In tube-fed bedridden patients with hypo-albuminemia, natural-killer cell activity may be associated with aging, body mass index, transferrin, and lymphocyte counts.
Protein Kinase C-θ (PKC-θ) in Natural Killer Cell Function and Anti-Tumor Immunity
Anel, Alberto; Aguiló, Juan I.; Catalán, Elena; Garaude, Johan; Rathore, Moeez G.; Pardo, Julián; Villalba, Martín
2012-01-01
The protein kinase C-θ (PKCθ), which is essential for T cell function and survival, is also required for efficient anti-tumor immune surveillance. Natural killer (NK) cells, which express PKCθ, play a prominent role in this process, mainly by elimination of tumor cells with reduced or absent major histocompatibility complex class-I (MHC-I) expression. This justifies the increased interest of the use of activated NK cells in anti-tumor immunotherapy in the clinic. The in vivo development of MHC-I-deficient tumors is much favored in PKCθ−/− mice compared with wild-type mice. Recent data offer some clues on the mechanism that could explain the important role of PKCθ in NK cell-mediated anti-tumor immune surveillance: some studies show that PKCθ is implicated in signal transduction and anti-tumoral activity of NK cells elicited by interleukin (IL)-12 or IL-15, while others show that it is implicated in NK cell functional activation mediated by certain killer-activating receptors. Alternatively, the possibility that PKCθ is involved in NK cell degranulation is discussed, since recent data indicate that it is implicated in microtubule-organizing center polarization to the immune synapse in CD4+ T cells. The implication of PKC isoforms in degranulation has been more extensively studied in cytotoxic T lymphocyte, and these studies will be also summarized. PMID:22783260
Lin, Mao; Liang, Shuzhen; Wang, Xiaohua; Liang, Yinqing; Zhang, Mingjie; Chen, Jibing; Niu, Lizhi; Xu, Kecheng
2017-10-10
In this study, the clinical efficacy of cryosurgery combined with allogenic natural killer cell immunotherapy for advanced hepatocellular cancer was evaluated. From October 2015 to March 2017, we enrolled 61 patients who met the enrollment criteria and divided them into two groups: 1) the simple cryoablation group (Cryo group, n = 26); and 2) the cryoablation combined with allogenic natural killer cells group (Cryo-NK group, n = 35), the safety and short-term effects were evaluated firstly, then the median progression-free survival, response rate and disease control rate were assessed. All adverse events experienced by the patients were recorded, and included local (e.g., pain, pleural effusion, and ascites) and systemic (e.g., chills, fatigue, and fever) reactions, fever was more frequent. Other possible seriously side effects (e.g., blood or bone marrow changes) were not detected. Combining allogeneic natural killer cells with cryoablation had a synergistic effect, not only enhancing the immune function, improving the quality of life of the patients, but also reducing the expression of AFP and significantly exhibiting good clinical efficacy of the patients. After a median follow-up of 8.7 months (3.9 -15.1months), median progression-free survival was higher in Cryo-NK (9.1 months) than in Cryo (7.6 months, P = 0.0107), median progression-free survival who received multiple natural killer was higher than who just received single natural killer (9.7 months vs.8.4 months, P = 0.0011, respectively), the response rate in Cryo-NK (60.0%) was higher than in Cryo (46.1%, P < 0.05), the disease control rate in Cryo-NK (85.7%) was higher than in Cryo group (69.2%, P < 0.01). Percutaneous cryoablation combined with allogeneic natural killer cell immunotherapy significantly increased median progression-free survival of advanced hepatocellular cancer patients. Multiple allogeneic natural killer cells infusion was associated with better prognosis to advanced hepatocellular cancer.
Lin, Mao; Liang, Shuzhen; Wang, Xiaohua; Liang, Yinqing; Zhang, Mingjie; Chen, Jibing; Niu, Lizhi; Xu, Kecheng
2017-01-01
In this study, the clinical efficacy of cryosurgery combined with allogenic natural killer cell immunotherapy for advanced hepatocellular cancer was evaluated. From October 2015 to March 2017, we enrolled 61 patients who met the enrollment criteria and divided them into two groups: 1) the simple cryoablation group (Cryo group, n = 26); and 2) the cryoablation combined with allogenic natural killer cells group (Cryo-NK group, n = 35), the safety and short-term effects were evaluated firstly, then the median progression-free survival, response rate and disease control rate were assessed. All adverse events experienced by the patients were recorded, and included local (e.g., pain, pleural effusion, and ascites) and systemic (e.g., chills, fatigue, and fever) reactions, fever was more frequent. Other possible seriously side effects (e.g., blood or bone marrow changes) were not detected. Combining allogeneic natural killer cells with cryoablation had a synergistic effect, not only enhancing the immune function, improving the quality of life of the patients, but also reducing the expression of AFP and significantly exhibiting good clinical efficacy of the patients. After a median follow-up of 8.7 months (3.9 –15.1months), median progression-free survival was higher in Cryo-NK (9.1 months) than in Cryo (7.6 months, P = 0.0107), median progression-free survival who received multiple natural killer was higher than who just received single natural killer (9.7 months vs.8.4 months, P = 0.0011, respectively), the response rate in Cryo-NK (60.0%) was higher than in Cryo (46.1%, P < 0.05), the disease control rate in Cryo-NK (85.7%) was higher than in Cryo group (69.2%, P < 0.01). Percutaneous cryoablation combined with allogeneic natural killer cell immunotherapy significantly increased median progression-free survival of advanced hepatocellular cancer patients. Multiple allogeneic natural killer cells infusion was associated with better prognosis to advanced hepatocellular cancer. PMID:29137237
Wagner, Julia A; Berrien-Elliott, Melissa M; Rosario, Maximillian; Leong, Jeffrey W; Jewell, Brea A; Schappe, Timothy; Abdel-Latif, Sara; Fehniger, Todd A
2017-03-01
Cytokine-induced memory-like natural killer (NK) cells differentiate after short-term preactivation with IL-12, IL-15, and IL-18 and display enhanced effector function in response to cytokines or tumor targets for weeks after the initial preactivation. Conventional NK cell function depends on a licensing signal, classically delivered by an inhibitory receptor engaging its cognate MHC class I ligand. How licensing status integrates with cytokine-induced memory-like NK cell responses is unknown. We investigated this interaction using killer cell immunoglobulin-like receptor- and HLA-genotyped primary human NK cells. Memory-like differentiation resulted in enhanced IFN-γ production triggered by leukemia targets or FcγRIIIa ligation within licensed NK cells, which exhibited the highest functionality of the NK cell subsets interrogated. IFN-γ production by unlicensed memory-like NK cells was also enhanced to a level comparable with that of licensed control NK cells. Mechanistically, differences in responses to FcγRIIIa-based triggering were not explained by alterations in key signaling intermediates, indicating that the underlying biology of memory-like NK cells is distinct from that of adaptive NK cells in human cytomegalovirus-positive individuals. Additionally, memory-like NK cells responded robustly to cytokine receptor restimulation with no impact of licensing status. These results demonstrate that both licensed and unlicensed memory-like NK cell populations have enhanced functionality, which may be translated to improve leukemia immunotherapy. Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.
Phototoxic effects of lysosome-associated genetically encoded photosensitizer KillerRed
NASA Astrophysics Data System (ADS)
Serebrovskaya, Ekaterina O.; Ryumina, Alina P.; Boulina, Maria E.; Shirmanova, Marina V.; Zagaynova, Elena V.; Bogdanova, Ekaterina A.; Lukyanov, Sergey A.; Lukyanov, Konstantin A.
2014-07-01
KillerRed is a unique phototoxic red fluorescent protein that can be used to induce local oxidative stress by green-orange light illumination. Here we studied phototoxicity of KillerRed targeted to cytoplasmic surface of lysosomes via fusion with Rab7, a small GTPase that is known to be attached to membranes of late endosomes and lysosomes. It was found that lysosome-associated KillerRed ensures efficient light-induced cell death similar to previously reported mitochondria- and plasma membrane-localized KillerRed. Inhibitory analysis demonstrated that lysosomal cathepsins play an important role in the manifestation of KillerRed-Rab7 phototoxicity. Time-lapse monitoring of cell morphology, membrane integrity, and nuclei shape allowed us to conclude that KillerRed-Rab7-mediated cell death occurs via necrosis at high light intensity or via apoptosis at lower light intensity. Potentially, KillerRed-Rab7 can be used as an optogenetic tool to direct target cell populations to either apoptosis or necrosis.
The prognostic value of natural killer cell infiltration in resected pulmonary adenocarcinoma.
Takanami, I; Takeuchi, K; Giga, M
2001-06-01
Natural cytotoxicity caused by mediated natural killer cells is believed to play an important role in host-cancer defense mechanisms. Immunohistochemically, we have detected natural killer cells in tissue specimens from patients with pulmonary adenocarcinoma and have assessed their clinical characteristics. Using the monoclonal antibody for CD57 specific marker for natural killer cells, we quantified natural killer cell infiltration in 150 patients with pulmonary adenocarcinoma who underwent curative tumor resection to investigate the relationship between natural killer cell counts and clinicopathologic factors and prognosis. The natural killer cell count was significantly related to the regulation of tumor progression, involving T classification, N classification, and stage (P =.01 for T classification or stage; P =.02 for N classification). A significant difference in the rate of patient survival was detected between those patients whose tumors had either high or low natural killer cell counts in both the overall and stage I groups (P =.0002 for the overall group; P =.049 for the stage I group). These data indicate that natural killer infiltration may contribute to the regulation of tumor progression and that the natural killer cell count can serve as a useful prognostic marker in overall and stage I pulmonary adenocarcinoma.
Age-related alteration of expression and function of TLRs and NK activity in oral candidiasis.
Oouchi, M; Hasebe, A; Hata, H; Segawa, T; Yamazaki, Y; Yoshida, Y; Kitagawa, Y; Shibata, K-I
2015-07-01
Roles of aging or immune responses mediated by Toll-like receptors and natural killer cell in the onset or progression of human candidiasis remain unclear. This study was designed to elucidate the roles using peripheral blood mononuclear cells from healthy donors and patients with oral candidiasis. Subjects tested were healthy volunteers and patients who visited Dental Clinical Division of Hokkaido University Hospital. The patients with oral candidiasis included 39 individuals (25-89 years of age) with major complaints on pain in oral mucosa and/or dysgeusia. Healthy volunteers include students (25-35 years of age) and teaching staffs (50-65 years of age) of Hokkaido University Graduate School of Dental Medicine. Functions of Toll-like receptors 2 and 4 were downregulated significantly and the natural killer activity was slightly, but not significantly downregulated in aged healthy volunteers compared with healthy young volunteers. Functions of Toll-like receptors 2 and 4 and the natural killer activity were significantly downregulated in patients with oral candidiasis compared with healthy volunteers. Downregulation of functions of Toll-like receptors 2 and 4 as well as natural killer activity is suggested to be associated with the onset or progression of oral candidiasis in human. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Developmental and Functional Control of Natural Killer Cells by Cytokines
Wu, Yang; Tian, Zhigang; Wei, Haiming
2017-01-01
Natural killer (NK) cells are effective in combating infections and tumors and as such are tempting for adoptive transfer therapy. However, they are not homogeneous but can be divided into three main subsets, including cytotoxic, tolerant, and regulatory NK cells, with disparate phenotypes and functions in diverse tissues. The development and functions of such NK cells are controlled by various cytokines, such as fms-like tyrosine kinase 3 ligand (FL), kit ligand (KL), interleukin (IL)-3, IL-10, IL-12, IL-18, transforming growth factor-β, and common-γ chain family cytokines, which operate at different stages by regulating distinct signaling pathways. Nevertheless, the specific roles of each cytokine that regulates NK cell development or that shapes different NK cell functions remain unclear. In this review, we attempt to describe the characteristics of each cytokine and the existing protocols to expand NK cells using different combinations of cytokines and feeder cells. A comprehensive understanding of the role of cytokines in NK cell development and function will aid the generation of better efficacy for adoptive NK cell treatment. PMID:28824650
Shirmanova, Marina; Yuzhakova, Diana; Snopova, Ludmila; Perelman, Gregory; Serebrovskaya, Ekaterina; Lukyanov, Konstantin; Turchin, Ilya; Subochev, Pavel; Lukyanov, Sergey; Kamensky, Vladislav; Zagaynova, Elena
2015-01-01
The strong phototoxicity of the red fluorescent protein KillerRed allows it to be considered as a potential genetically encoded photosensitizer for the photodynamic therapy (PDT) of cancer. The advantages of KillerRed over chemical photosensitizers are its expression in tumor cells transduced with the appropriate gene and direct killing of cells through precise damage to any desired cell compartment. The ability of KillerRed to affect cell division and to induce cell death has already been demonstrated in cancer cell lines in vitro and HeLa tumor xenografts in vivo. However, the further development of this approach for PDT requires optimization of the method of treatment. In this study we tested the continuous wave (593 nm) and pulsed laser (584 nm, 10 Hz, 18 ns) modes to achieve an antitumor effect. The research was implemented on CT26 subcutaneous mouse tumors expressing KillerRed in fusion with histone H2B. The results showed that the pulsed mode provided a higher rate of photobleaching of KillerRed without any temperature increase on the tumor surface. PDT with the continuous wave laser was ineffective against CT26 tumors in mice, whereas the pulsed laser induced pronounced histopathological changes and inhibition of tumor growth. Therefore, we selected an effective regimen for PDT when using the genetically encoded photosensitizer KillerRed and pulsed laser irradiation.
Yu, Junli; Venstrom, Jeffrey M; Liu, Xiao-Rong; Pring, James; Hasan, Reenat S; O'Reilly, Richard J; Hsu, Katharine C
2009-04-16
Alloreactive natural killer (NK) cells are an important influence on hematopoietic stem cell transplantation (HSCT) outcome. In HLA-mismatched HSCT, alloreactivity occurs when licensed donor NK cells expressing inhibitory killer Ig-like receptors (KIR) for donor MHC class I ligands recognize the lack of the class I ligands in the mismatched recipient ("missing self"). Studies in HLA-matched HSCT, however, have also demonstrated improved outcome in patients lacking class I ligands for donor inhibitory KIR ("missing ligand"), indicating that classically nonlicensed donor NK cells expressing KIR for non-self MHC class I ligands may exhibit functional competence in HSCT. We examined NK function in 16 recipients of T cell-depleted allografts from HLA-identical or KIR-ligand matched donors after myeloablative therapy. After HSCT, nonlicensed NK cells expressing inhibitory KIR for non-self class I exhibit robust intracellular IFN-gamma and cytotoxic response to target cells lacking cognate ligand, gradually becoming tolerized to self by day 100. These findings could not be correlated with cytokine environment or phenotypic markers of NK development, nor could they be attributed to non-KIR receptors such as CD94/NKG2A. These findings confirm that NK alloreactivity can occur in HLA-matched HSCT, where tolerance to self is either acquired by the stem cell-derived NK cell after exiting the bone marrow or where tolerance to self can be temporarily overcome.
Classification of human natural killer cells based on migration behavior and cytotoxic response.
Vanherberghen, Bruno; Olofsson, Per E; Forslund, Elin; Sternberg-Simon, Michal; Khorshidi, Mohammad Ali; Pacouret, Simon; Guldevall, Karolin; Enqvist, Monika; Malmberg, Karl-Johan; Mehr, Ramit; Önfelt, Björn
2013-02-21
Despite intense scrutiny of the molecular interactions between natural killer (NK) and target cells, few studies have been devoted to dissection of the basic functional heterogeneity in individual NK cell behavior. Using a microchip-based, time-lapse imaging approach allowing the entire contact history of each NK cell to be recorded, in the present study, we were able to quantify how the cytotoxic response varied between individual NK cells. Strikingly, approximately half of the NK cells did not kill any target cells at all, whereas a minority of NK cells was responsible for a majority of the target cell deaths. These dynamic cytotoxicity data allowed categorization of NK cells into 5 distinct classes. A small but particularly active subclass of NK cells killed several target cells in a consecutive fashion. These "serial killers" delivered their lytic hits faster and induced faster target cell death than other NK cells. Fast, necrotic target cell death was correlated with the amount of perforin released by the NK cells. Our data are consistent with a model in which a small fraction of NK cells drives tumor elimination and inflammation.
Petri, Robert Michael; Hackel, Alexander; Hahnel, Katrin; Dumitru, Claudia Alexandra; Bruderek, Kirsten; Flohe, Stefanie B; Paschen, Annette; Lang, Stephan; Brandau, Sven
2017-09-12
The interaction of mesenchymal stromal cells (MSCs) with natural killer (NK) cells is traditionally thought of as a static inhibitory model, whereby resting MSCs inhibit NK cell effector function. Here, we use a dynamic in vitro system of poly(I:C) stimulation to model the interaction of NK cells and tissue-resident MSCs in the context of infection or tissue injury. The experiments suggest a time-dependent system of regulation and feedback, where, at early time points, activated MSCs secrete type I interferon to enhance NK cell effector function, while at later time points TGF-β and IL-6 limit NK cell effector function and terminate inflammatory responses by induction of a regulatory senescent-like NK cell phenotype. Importantly, feedback of these regulatory NK cells to MSCs promotes survival, proliferation, and pro-angiogenic properties. Our data provide additional insight into the interaction of stromal cells and innate immune cells and suggest a model of time-dependent MSC polarization and licensing. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
CD161 Defines a Functionally Distinct Subset of Pro-Inflammatory Natural Killer Cells
Kurioka, Ayako; Cosgrove, Cormac; Simoni, Yannick; van Wilgenburg, Bonnie; Geremia, Alessandra; Björkander, Sophia; Sverremark-Ekström, Eva; Thurnheer, Christine; Günthard, Huldrych F.; Khanna, Nina; Aubert, V; Arancibia-Cárcamo, CV; Walker, Lucy Jane; Arancibia-Cárcamo, Carolina V.; Newell, Evan W.; Willberg, Christian B.; Klenerman, Paul
2018-01-01
CD161 is a C-type lectin-like receptor expressed on the majority of natural killer (NK) cells; however, the significance of CD161 expression on NK cells has not been comprehensively investigated. Recently, we found that CD161 expression identifies a transcriptional and innate functional phenotype that is shared across various T cell populations. Using mass cytometry and microarray experiments, we demonstrate that this functional phenotype extends to NK cells. CD161 marks NK cells that have retained the ability to respond to innate cytokines during their differentiation, and is lost upon cytomegalovirus-induced maturation in both healthy and human immunodeficiency virus (HIV)-infected patients. These pro-inflammatory NK cells are present in the inflamed lamina propria where they are enriched for integrin CD103 expression. Thus, CD161 expression identifies NK cells that may contribute to inflammatory disease pathogenesis and correlates with an innate responsiveness to cytokines in both T and NK cells. PMID:29686665
Activation of natural killer cells by hepatitis C virus particles in vitro
Farag, M M S; Weigand, K; Encke, J; Momburg, F
2011-01-01
Little is known about the ability of hepatitis C virus (HCV) to alter early innate immune responses in infected patients. Previous studies have shown that natural killer (NK) cells are functionally impaired after interaction of recombinant HCV glycoprotein E2 with the co-stimulatory CD81 molecule in vitro; however, the functional consequences of a prolonged contact of NK cells with HCV particles have remained unclear. We have examined the phenotypes of purified, interleukin-2-activated NK cells from healthy donors and HCV genotype 1b patients after culture for 5 days with HCV pseudoparticles (HCVpp) and serum samples containing HCV genotype 1b. NK cells from healthy donors and chronic HCV patients were found to up-regulate receptors associated with activation (NKp46, NKp44, NKp30, NKG2D), while NK receptors from the killer cell immunoglobulin-like receptor family (KIR/CD158), predominantly having an inhibitory function, were significantly down-modulated after culture in the presence of HCV particles compared with control cultures of NK cells. HCV-infected sera and HCVpp elicited significantly higher secretion of the NK effector lymphokines interferon-γ and tumour necrosis factor-α. Furthermore, HCV stimulated the cytotoxic potential of NK cells from normal donors and patients. The enhanced activation of NK cells after prolonged culture with HCVpp or HCV-containing sera for 5 days suggests that these innate effector cells may play an important role in viral control during early phases of HCV infection. PMID:21682720
ERAP1 regulates natural killer cell function by controlling the engagement of inhibitory receptors.
Cifaldi, Loredana; Romania, Paolo; Falco, Michela; Lorenzi, Silvia; Meazza, Raffaella; Petrini, Stefania; Andreani, Marco; Pende, Daniela; Locatelli, Franco; Fruci, Doriana
2015-03-01
The endoplasmic reticulum aminopeptidase ERAP1 regulates innate and adaptive immune responses by trimming peptides for presentation by MHC class I (MHC-I) molecules. Herein, we demonstrate that genetic or pharmacological inhibition of ERAP1 on human tumor cell lines perturbs their ability to engage several classes of inhibitory receptors by their specific ligands, including killer cell Ig-like receptors (KIR) by classical MHC-I-peptide (pMHC-I) complexes and the lectin-like receptor CD94-NKG2A by nonclassical pMHC-I complexes, in each case leading to natural killer (NK) cell killing. The protective effect of pMHC-I complexes could be restored in ERAP1-deficient settings by the addition of known high-affinity peptides, suggesting that ERAP1 was needed to positively modify the affinity of natural ligands. Notably, ERAP1 inhibition enhanced the ability of NK cells to kill freshly established human lymphoblastoid cell lines from autologous or allogeneic sources, thereby promoting NK cytotoxic activity against target cells that would not be expected because of KIR-KIR ligand matching. Overall, our results identify ERAP1 as a modifier to leverage immune functions that may improve the efficacy of NK cell-based approaches for cancer immunotherapy. ©2015 American Association for Cancer Research.
Natural killer cell receptor genes in the family Equidae: not only Ly49.
Futas, Jan; Horin, Petr
2013-01-01
Natural killer (NK) cells have important functions in immunity. NK recognition in mammals can be mediated through killer cell immunoglobulin-like receptors (KIR) and/or killer cell lectin-like Ly49 receptors. Genes encoding highly variable NK cell receptors (NKR) represent rapidly evolving genomic regions. No single conservative model of NKR genes was observed in mammals. Single-copy low polymorphic NKR genes present in one mammalian species may expand into highly polymorphic multigene families in other species. In contrast to other non-rodent mammals, multiple Ly49-like genes appear to exist in the horse, while no functional KIR genes were observed in this species. In this study, Ly49 and KIR were sought and their evolution was characterized in the entire family Equidae. Genomic sequences retrieved showed the presence of at least five highly conserved polymorphic Ly49 genes in horses, asses and zebras. These findings confirmed that the expansion of Ly49 occurred in the entire family. Several KIR-like sequences were also identified in the genome of Equids. Besides a previously identified non-functional KIR-Immunoglobulin-like transcript fusion gene (KIR-ILTA) and two putative pseudogenes, a KIR3DL-like sequence was analyzed. In contrast to previous observations made in the horse, the KIR3DL sequence, genomic organization and mRNA expression suggest that all Equids might produce a functional KIR receptor protein molecule with a single non-mutated immune tyrosine-based inhibition motif (ITIM) domain. No evidence for positive selection in the KIR3DL gene was found. Phylogenetic analysis including rhinoceros and tapir genomic DNA and deduced amino acid KIR-related sequences showed differences between families and even between species within the order Perissodactyla. The results suggest that the order Perissodactyla and its family Equidae with expanded Ly49 genes and with a potentially functional KIR gene may represent an interesting model for evolutionary biology of NKR genes.
Natural Killer Cell Receptor Genes in the Family Equidae: Not only Ly49
Futas, Jan; Horin, Petr
2013-01-01
Natural killer (NK) cells have important functions in immunity. NK recognition in mammals can be mediated through killer cell immunoglobulin-like receptors (KIR) and/or killer cell lectin-like Ly49 receptors. Genes encoding highly variable NK cell receptors (NKR) represent rapidly evolving genomic regions. No single conservative model of NKR genes was observed in mammals. Single-copy low polymorphic NKR genes present in one mammalian species may expand into highly polymorphic multigene families in other species. In contrast to other non-rodent mammals, multiple Ly49-like genes appear to exist in the horse, while no functional KIR genes were observed in this species. In this study, Ly49 and KIR were sought and their evolution was characterized in the entire family Equidae. Genomic sequences retrieved showed the presence of at least five highly conserved polymorphic Ly49 genes in horses, asses and zebras. These findings confirmed that the expansion of Ly49 occurred in the entire family. Several KIR-like sequences were also identified in the genome of Equids. Besides a previously identified non-functional KIR-Immunoglobulin-like transcript fusion gene (KIR-ILTA) and two putative pseudogenes, a KIR3DL-like sequence was analyzed. In contrast to previous observations made in the horse, the KIR3DL sequence, genomic organization and mRNA expression suggest that all Equids might produce a functional KIR receptor protein molecule with a single non-mutated immune tyrosine-based inhibition motif (ITIM) domain. No evidence for positive selection in the KIR3DL gene was found. Phylogenetic analysis including rhinoceros and tapir genomic DNA and deduced amino acid KIR-related sequences showed differences between families and even between species within the order Perissodactyla. The results suggest that the order Perissodactyla and its family Equidae with expanded Ly49 genes and with a potentially functional KIR gene may represent an interesting model for evolutionary biology of NKR genes. PMID:23724088
Takehara, Kiyoto; Yano, Shuya; Tazawa, Hiroshi; Kishimoto, Hiroyuki; Narii, Nobuhiro; Mizuguchi, Hiroyuki; Urata, Yasuo; Kagawa, Shunsuke; Fujiwara, Toshiyoshi; Hoffman, Robert M
2017-08-18
Melanoma is a highly recalcitrant cancer and transformative therapy is necessary for the cure of this disease. We recently developed a telomerase-dependent adenovirus containing the fluorescent protein Killer-Red. In the present report, we first determined the efficacy of Killer-Red adenovirus combined with laser irradiation on human melanoma cell lines in vitro. Cell viability of human melanoma cells was reduced in a dose-dependent and irradiation-time-dependent manner. We used an intradermal xenografted melanoma model in nude mice to determine efficacy of the Killer-Red adenovirus. Intratumoral injection of Killer-Red adenovirus, combined with laser irradiation, eradicated the melanoma indicating the potential of a new paradigm of cancer therapy.
Emmer, P M; Nelen, W L; Steegers, E A; Hendriks, J C; Veerhoek, M; Joosten, I
2000-05-01
For diagnostic purposes we assessed peripheral natural killer (NK) cell cytotoxicity and NK and T cell numbers to assess their putative predictive value in recurrent spontaneous abortion (RSA). A total of 43 women with subsequent pregnancy, 37 healthy controls and 39 women successfully partaking in an in-vitro fertilization (IVF) procedure, were included in the study. We show that before pregnancy, levels of NK cytotoxicity and numbers of both single CD56(pos) and double CD56(pos)CD16(pos) cells were similar between RSA women and controls. But notably, within the RSA group, NK cell numbers of <12% were strongly associated with a subsequent pregnancy carried to term. Supplementation of folic acid led to an increase of single CD56(pos) cells, but cytotoxic function appeared unaffected. The expression pattern of killer inhibitory receptors on CD56(pos) cells was not different between patients and controls. A longitudinal study revealed that, compared with controls, in RSA women higher numbers of double CD56(pos)CD16(pos) cells were present during early pregnancy, paralleled by an increase in cytotoxic NK cell reactivity. The single CD56(pos) population decreased in number. In conclusion, the analysis of peripheral NK cell characteristics appears a suitable diagnostic tool in RSA. Immunomodulation aimed at NK cell function appears a promising therapeutic measure.
Natural killer cell biology illuminated by primary immunodeficiency syndromes in humans.
Voss, Matthias; Bryceson, Yenan T
2017-04-01
Natural killer (NK) cells are innate immune cytotoxic effector cells well known for their role in antiviral immunity and tumor immunosurveillance. In parts, this knowledge stems from rare inherited immunodeficiency disorders in humans that abrogate NK cell function leading to immune impairments, most notably associated with a high susceptibility to viral infections. Phenotypically, these disorders range from deficiencies selectively affecting NK cells to complex general immune defects that affect NK cells but also other immune cell subsets. Moreover, deficiencies may be associated with reduced NK cell numbers or rather impair specific NK cell effector functions. In recent years, genetic defects underlying the various NK cell deficiencies have been uncovered and have triggered investigative efforts to decipher the molecular mechanisms underlying these disorders. Here we review the associations between inherited human diseases and NK cell development as well as function, with a particular focus on defects in NK cell exocytosis and cytotoxicity. Furthermore we outline how reports of diverse genetic defects have shaped our understanding of NK cell biology. Copyright © 2015. Published by Elsevier Inc.
Background Modified function of immune cells in nasal secretions may playa role in the enhanced susceptibility to resp iratory viruses that is seen in smokers. Innate immune cells in nasal secretions have largely been characterized by cellular differentials using morphologic c...
Human cytomegalovirus infection elicits new decidual natural killer cell effector functions.
Siewiera, Johan; El Costa, Hicham; Tabiasco, Julie; Berrebi, Alain; Cartron, Géraldine; Le Bouteiller, Philippe; Bouteiller, Philippe; Jabrane-Ferrat, Nabila
2013-01-01
During the first trimester of pregnancy the uterus is massively infiltrated by decidual natural killer cells (dNK). These cells are not killers, but they rather provide a microenvironment that is propitious to healthy placentation. Human cytomegalovirus (HCMV) is the most common cause of intrauterine viral infections and a known cause of severe birth defects or fetal death. The rate of HCMV congenital infection is often low in the first trimester of pregnancy. The mechanisms controlling HCMV spreading during pregnancy are not yet fully revealed, but evidence indicating that the innate immune system plays a role in controlling HCMV infection in healthy adults exists. In this study, we investigated whether dNK cells could be involved in controlling viral spreading and in protecting the fetus against congenital HCMV infection. We found that freshly isolated dNK cells acquire major functional and phenotypic changes when they are exposed to HCMV-infected decidual autologous fibroblasts. Functional studies revealed that dNK cells, which are mainly cytokines and chemokines producers during normal pregnancy, become cytotoxic effectors upon their exposure to HCMV-infected autologous decidual fibroblasts. Both the NKG2D and the CD94/NKG2C or 2E activating receptors are involved in the acquired cytotoxic function. Moreover, we demonstrate that CD56(pos) dNK cells are able to infiltrate HCMV-infected trophoblast organ culture ex-vivo and to co-localize with infected cells in situ in HCMV-infected placenta. Taken together, our results present the first evidence suggesting the involvement of dNK cells in controlling HCMV intrauterine infection and provide insights into the mechanisms through which these cells may operate to limit the spreading of viral infection to fetal tissues.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Back, J.; Malchiodi, E; Cho, S
2009-01-01
Certain cell-surface receptors engage ligands expressed on juxtaposed cells and ligands on the same cell. The structural basis for trans versus cis binding is not known. Here, we showed that Ly49 natural killer (NK) cell receptors bound two MHC class I (MHC-I) molecules in trans when the two ligand-binding domains were backfolded onto the long stalk region. In contrast, dissociation of the ligand-binding domains from the stalk and their reorientation relative to the NK cell membrane allowed monovalent binding of MHC-I in cis. The distinct conformations (backfolded and extended) define the structural basis for cis-trans binding by Ly49 receptors andmore » explain the divergent functional consequences of cis versus trans interactions. Further analyses identified specific stalk segments that were not required for MHC-I binding in trans but were essential for inhibitory receptor function. These data identify multiple distinct roles of stalk regions for receptor function.« less
Veluchamy, John P.; Kok, Nina; van der Vliet, Hans J.; Verheul, Henk M. W.; de Gruijl, Tanja D.; Spanholtz, Jan
2017-01-01
Natural killer (NK) cells are critical immune effector cells in the fight against cancer. As NK cells in cancer patients are highly dysfunctional and reduced in number, adoptive transfer of large numbers of cytolytic NK cells and their potential to induce relevant antitumor responses are widely explored in cancer immunotherapy. Early studies from autologous NK cells have failed to demonstrate significant clinical benefit. In this review, the clinical benefits of adoptively transferred allogeneic NK cells in a transplant and non-transplant setting are compared and discussed in the context of relevant NK cell platforms that are being developed and optimized by various biotech industries with a special focus on augmenting NK cell functions. PMID:28620386
Chen, Xiaoyan; Mariee, Najat; Jiang, Lingming; Liu, Yingyu; Wang, Chi Chiu; Li, Tin Chiu; Laird, Susan
2017-12-01
Uterine natural killer cells are the major leukocytes present in the periimplantation endometrium. Previous studies have found controversial differences in uterine natural killer cell percentage in women with recurrent reproductive failure compared with fertile controls. We sought to compare the uterine natural killer cell percentage in women with recurrent reproductive failure and fertile controls. This was a retrospective study carried out in university hospitals. A total of 215 women from 3 university centers participated in the study, including 97 women with recurrent miscarriage, 34 women with recurrent implantation failure, and 84 fertile controls. Endometrial biopsy samples were obtained precisely 7 days after luteinization hormone surge in a natural cycle. Endometrial sections were immunostained for CD56 and cell counting was performed by a standardized protocol. Results were expressed as percentage of positive uterine natural killer cell/total stromal cells. The median uterine natural killer cell percentage in Chinese ovulatory fertile controls in natural cycles was 2.5% (range 0.9-5.3%). Using 5th and 95th percentile to define the lower and upper limits of uterine natural killer cell percentage, the reference range was 1.2-4.5%. Overall, the groups with recurrent reproductive failure had significantly higher uterine natural killer cell percentage than the controls (recurrent miscarriage: median 3.2%, range 0.6-8.8%; recurrent implantation failure: median 3.1%, range 0.8-8.3%). However, there was a subset of both groups (recurrent miscarriage: 16/97; recurrent implantation failure: 6/34) that had lower uterine natural killer cell percentage compared to fertile controls. A reference range for uterine natural killer cell percentage in fertile women was established. Women with recurrent reproductive failure had uterine natural killer cell percentages both above and below the reference range. Copyright © 2017 Elsevier Inc. All rights reserved.
Activation of natural killer cells by hepatitis C virus particles in vitro.
Farag, M M S; Weigand, K; Encke, J; Momburg, F
2011-09-01
Little is known about the ability of hepatitis C virus (HCV) to alter early innate immune responses in infected patients. Previous studies have shown that natural killer (NK) cells are functionally impaired after interaction of recombinant HCV glycoprotein E2 with the co-stimulatory CD81 molecule in vitro; however, the functional consequences of a prolonged contact of NK cells with HCV particles have remained unclear. We have examined the phenotypes of purified, interleukin-2-activated NK cells from healthy donors and HCV genotype 1b patients after culture for 5 days with HCV pseudoparticles (HCVpp) and serum samples containing HCV genotype 1b. NK cells from healthy donors and chronic HCV patients were found to up-regulate receptors associated with activation (NKp46, NKp44, NKp30, NKG2D), while NK receptors from the killer cell immunoglobulin-like receptor family (KIR/CD158), predominantly having an inhibitory function, were significantly down-modulated after culture in the presence of HCV particles compared with control cultures of NK cells. HCV-infected sera and HCVpp elicited significantly higher secretion of the NK effector lymphokines interferon-γ and tumour necrosis factor-α. Furthermore, HCV stimulated the cytotoxic potential of NK cells from normal donors and patients. The enhanced activation of NK cells after prolonged culture with HCVpp or HCV-containing sera for 5 days suggests that these innate effector cells may play an important role in viral control during early phases of HCV infection. © 2011 The Authors. Clinical and Experimental Immunology © 2011 British Society for Immunology.
Domogala, Anna; Madrigal, J Alejandro; Saudemont, Aurore
2016-06-01
Natural killer (NK) cells offer the potential for a powerful cellular immunotherapy because they can target malignant cells without being direct effectors of graft-versus-host disease. We have previously shown that high numbers of functional NK cells can be differentiated in vitro from umbilical cord blood (CB) CD34(+) cells. To develop a readily available, off-the-shelf cellular product, it is essential that NK cells differentiated in vitro can be frozen and thawed while maintaining the same phenotype and functions. We evaluated the phenotype and function of fresh and frozen NK cells differentiated in vitro. We also assessed whether the concentration of NK cells at the time of freezing had an impact on cell viability. We found that cell concentration of NK cells at the time of freezing did not have an impact on their viability and on cell recovery post-thaw. Moreover, freezing of differentiated NK cells in vitro did not affect their phenotype, cytotoxicity and degranulation capacity toward K562 cells, cytokine production and proliferation. We are therefore able to generate large numbers of functional NK cells from CB CD34(+) cells that maintain the same phenotype and function post-cryopreservation, which will allow for multiple infusions of a highly cytotoxic NK cell product. Copyright © 2016 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.
Takahashi, Naomi; Sugaya, Makoto; Suga, Hiraku; Oka, Tomonori; Kawaguchi, Makiko; Miyagaki, Tomomitsu; Fujita, Hideki; Inozume, Takashi; Sato, Shinichi
2017-08-01
Immune checkpoint therapy, which targets regulatory pathways in T cells to enhance antitumor immune responses, has led to important clinical advances. CD155 is expressed in various types of cancer, and this surface molecule on tumor cells functions either as a co-stimulatory molecule or a co-inhibitory molecule, depending on its receptor. CD226, a CD155 ligand, is mainly expressed on natural killer cells and CD8 + T cells, playing important roles in natural killer cell-mediated cytotoxicity. In this study, we investigated the expression and function of CD155 and CD226 in cutaneous T-cell lymphoma (CTCL). CD155 was strongly expressed on tumor cells and CD155 mRNA expression levels were increased in CTCL lesional skin. CD226 expression on natural killer cells and CD8 + cells in peripheral blood of CTCL patients was decreased. On the other hand, serum CD226 levels were significantly elevated in CTCL patients, strongly reflecting disease activity, suggesting that soluble CD226 in sera was generated by shedding of its membrane form. Recombinant CD226 itself showed cytotoxic activity against CD155-expressing CTCL cells in vitro. These data suggest that soluble CD226 elevated in sera of CTCL patients would be important for tumor immunity by interacting with CD155 on tumor cells. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
Rajalingam, Raja
2016-01-01
Natural killer (NK) cells of the innate immune system are cytotoxic lymphocytes that play an important roles following transplantation of solid organs and hematopoietic stem cells. Recognition of self-human leukocyte antigen (HLA) class I molecules by inhibitory killer cell immunoglobulin-like receptors (KIRs) is involved in the calibration of NK cell effector capacities during the developmental stage, allowing the subsequent recognition and elimination of target cells with decreased expression of self-HLA class I (due to virus infection or tumor transformation) or HLA class I disparities (in the setting of allogeneic transplantation). NK cells expressing an inhibitory KIR-binding self-HLA can be activated when confronted with allografts lacking a ligand for the inhibitory receptor. Following the response of the adaptive immune system, NK cells can further destroy allograft endothelium by antibody-dependent cell-mediated cytotoxicity (ADCC), triggered through cross-linking of the CD16 Fc receptor by donor-specific antibodies bound to allograft. Upon recognizing allogeneic target cells, NK cells also secrete cytokines and chemokines that drive maturation of dendritic cells to promote cellular and humoral adaptive immune responses against the allograft. The cumulative activating and inhibitory signals generated by ligation of the receptors regulates mature NK cell killing of target cells and their production of cytokines and chemokines. This review summarizes the role of NK cells in allograft rejection and proposes mechanistic concepts that indicate a prominent role for KIR-HLA interactions in facilitating NK cells for Fc receptor-mediated ADCC effector function involved in antibody-mediated rejection of solid organ transplants.
Ghiringhelli, Francois; Ménard, Cédric; Martin, Francois; Zitvogel, Laurence
2006-12-01
Tumor immunosurveillance relies on cognate immune effectors [lymphocytes and interferon-gamma (IFN-gamma)] and innate immunity [natural killer (NK) cells, natural killer group 2, member D (NKG2D) ligands, perforin/granzyme, and tumor necrosis factor-related apoptosis-inducing ligand]. In parallel, tumor cells promote the expansion of CD4(+)CD25(+) regulatory T cells (Tregs) that counteract T-cell-based anti-tumor immunity. Moreover, accumulating evidence points to a critical role for Tregs in dampening NK cell immune responses. This review summarizes the findings showing that Tregs suppress NK cell effector functions in vitro and in vivo, i.e. homeostatic proliferation, cytotoxicity, and interleukin-12-mediated IFN-gamma production. The molecular mechanism involve selective expression of membrane-bound transforming growth factor-beta on Tregs, which downregulate NKG2D expression on NK cells in vitro and in vivo. The regulatory events dictating NK cell suppression by Tregs have been studied and are discussed. The pathological relevance of the Treg-NK cell interaction has been brought up in tumor models and in patients with cancer. Consequently, inhibition of Tregs through pharmacological interventions should be considered during NK-cell-based immunotherapy of cancer.
Medina, K; Carrau, F M; Gioia, O; Bracesco, N
1997-01-01
The competition between selected or commercial killer strains of type K2 and sensitive commercial strains of Saccharomyces cerevisiae was studied under various conditions in sterile grape juice fermentations. The focus of this study was the effect of yeast inoculation levels and the role of assimilable nitrogen nutrition on killer activity. A study of the consumption of free amino nitrogen (FAN) by pure and mixed cultures of killer and sensitive cells showed no differences between the profiles of nitrogen assimilation in all cases, and FAN was practically depleted in the first 2 days of fermentation. The effect of the addition of assimilable nitrogen and the size of inoculum was examined in mixed killer and sensitive strain competitions. Stuck and sluggish wine fermentations were observed to depend on nitrogen availability when the ratio of killer to sensitive cells was low (1:10 to 1:100). A relationship between the initial assimilable nitrogen content of must and the proportion of killer cells during fermentation was shown. An indirect relationship was found between inoculum size and the percentage of killer cells: a smaller inoculum resulted in a higher proportion of killer cells in grape juice fermentations. In all cases, wines obtained with pure-culture fermentations were preferred to mixed-culture fermentations by sensory analysis. The reasons why killer cells do not finish fermentation under competitive conditions with sensitive cells are discussed. PMID:9212430
Manufacturing Natural Killer Cells as Medicinal Products
Chabannon, Christian; Mfarrej, Bechara; Guia, Sophie; Ugolini, Sophie; Devillier, Raynier; Blaise, Didier; Vivier, Eric; Calmels, Boris
2016-01-01
Natural Killer (NK) cells are innate lymphoid cells (ILC) with cytotoxic and regulatory properties. Their functions are tightly regulated by an array of inhibitory and activating receptors, and their mechanisms of activation strongly differ from antigen recognition in the context of human leukocyte antigen presentation as needed for T-cell activation. NK cells thus offer unique opportunities for new and improved therapeutic manipulation, either in vivo or in vitro, in a variety of human diseases, including cancers. NK cell activity can possibly be modulated in vivo through direct or indirect actions exerted by small molecules or monoclonal antibodies. NK cells can also be adoptively transferred following more or less substantial modifications through cell and gene manufacturing, in order to empower them with new or improved functions and ensure their controlled persistence and activity in the recipient. In the present review, we will focus on the technological and regulatory challenges of NK cell manufacturing and discuss conditions in which these innovative cellular therapies can be brought to the clinic. PMID:27895646
Kusumi, Maki; Yamashita, Takahiro; Fujii, Tomoyuki; Nagamatsu, Takeshi; Kozuma, Shiro; Taketani, Yuji
2006-06-01
The balance of inhibitory and activating natural killer (NK) receptors on maternal decidual NK cells, most of which are CD56bright, is thought to be crucial for the proper growth of trophoblasts in placenta. A lectin-like NK receptor, CD94/NKG2, is the receptor for human leukocyte antigen (HLA)-E, which is expressed on trophoblasts. To clarify the mechanism regulating the activity of decidual NK cells during pregnancy, we investigated the expression patterns of inhibitory NK receptor, CD94/NKG2A, and activating receptor, CD94/NKG2C, on decidual NK cells in an early stage of normal pregnancy and compared them with those on peripheral NK cells, most of which are CD56dim. The rate of NKG2A-positive cells was significantly higher for decidual CD56bright NK cells than for peripheral CD56dim NK cells, but the rates of NKG2C-positive cells were comparable between the two cell types. Interestingly, peripheral CD56dim NK cells reciprocally expressed inhibitory NKG2A and activating NKG2C, but decidual CD56bright NK cells that expressed activating NKG2C simultaneously expressed inhibitory NKG2A. The co-expression of inhibitory and activating NKG2 receptors may fine-tune the immunoregulatory functions of the decidual NK cells to control the trophoblast invasion in constructing placenta.
Newtonian cell interactions shape natural killer cell education.
Goodridge, Jodie P; Önfelt, Björn; Malmberg, Karl-Johan
2015-09-01
Newton's third law of motion states that for every action on a physical object there is an equal and opposite reaction. The dynamic change in functional potential of natural killer (NK) cells during education bears many features of such classical mechanics. Cumulative physical interactions between cells, under a constant influence of homeostatic drivers of differentiation, lead to a reactive spectrum that ultimately shapes the functionality of each NK cell. Inhibitory signaling from an array of self-specific receptors appear not only to suppress self-reactivity but also aid in the persistence of effector functions over time, thereby allowing the cell to gradually build up a functional potential. Conversely, the frequent non-cytolytic interactions between normal cells in the absence of such inhibitory signaling result in continuous stimulation of the cells and attenuation of effector function. Although an innate cell, the degree to which the fate of the NK cell is predetermined versus its ability to adapt to its own environment can be revealed through a Newtonian view of NK cell education, one which is both chronological and dynamic. As such, the development of NK cell functional diversity is the product of qualitatively different physical interactions with host cells, rather than simply the sum of their signals or an imprint based on intrinsically different transcriptional programs. © 2015 The Authors. Immunological Reviews Published by John Wiley & Sons Ltd.
Dok1 and Dok2 proteins regulate natural killer cell development and function
Celis-Gutierrez, Javier; Boyron, Marilyn; Walzer, Thierry; Pandolfi, Pier Paolo; Jonjić, Stipan; Olive, Daniel; Dalod, Marc; Vivier, Eric; Nunès, Jacques A
2014-01-01
Natural killer (NK) cells are involved in immune responses against tumors and microbes. NK-cell activation is regulated by intrinsic and extrinsic mechanisms that ensure NK tolerance and efficacy. Here, we show that the cytoplasmic signaling molecules Dok1 and Dok2 are tyrosine phosphorylated upon NK-cell activation. Overexpression of Dok proteins in human NK cells reduces cell activation induced by NK-cell-activating receptors. Dok1 and Dok2 gene ablation in mice induces an NK-cell maturation defect and leads to increased IFN-γ production induced by activating receptors. Taken together, these results reveal that Dok1 and Dok2 proteins are involved in an intrinsic negative feedback loop downstream of NK-cell-activating receptors in mouse and human. PMID:24963146
Baytak, Esra; Gong, Qiang; Akman, Burcu; Yuan, Hongling; Chan, Wing C; Küçük, Can
2017-05-01
Natural killer/T-cell lymphoma is a rare but aggressive neoplasm with poor prognosis. Despite previous reports that showed potential tumor suppressors, such as PRDM1 or oncogenes associated with the etiology of this malignancy, the role of long non-coding RNAs in natural killer/T-cell lymphoma pathobiology has not been addressed to date. Here, we aim to identify cancer-associated dysregulated long non-coding RNAs and signaling pathways or biological processes associated with these long non-coding RNAs in natural killer/T-cell lymphoma cases and to identify the long non-coding RNAs transcriptionally regulated by PRDM1. RNA-Seq analysis revealed 166 and 66 long non-coding RNAs to be significantly overexpressed or underexpressed, respectively, in natural killer/T-cell lymphoma cases compared with resting or activated normal natural killer cells. Novel long non-coding RNAs as well as the cancer-associated ones such as SNHG5, ZFAS1, or MIR155HG were dysregulated. Interestingly, antisense transcripts of many growth-regulating genes appeared to be transcriptionally deregulated. Expression of ZFAS1, which is upregulated in natural killer/T-cell lymphoma cases, showed association with growth-regulating pathways such as stabilization of P53, regulation of apoptosis, cell cycle, or nuclear factor-kappa B signaling in normal and neoplastic natural killer cell samples. Consistent with the tumor suppressive role of PRDM1, we identified MIR155HG and TERC to be transcriptionally downregulated by PRDM1 in two PRDM1-null NK-cell lines when it is ectopically expressed. In conclusion, this is the first study that identified long non-coding RNAs whose expression is dysregulated in natural killer/T-cell lymphoma cases. These findings suggest that ZFAS1 and other dysregulated long non-coding RNAs may be involved in natural killer/T-cell lymphoma pathobiology through regulation of cancer-related genes, and loss-of-PRDM1 expression in natural killer/T-cell lymphomas may contribute to overexpression of MIR155HG; thereby promoting tumorigenesis.
Liang, Shuzhen; Xu, Kecheng; Niu, Lizhi; Wang, Xiaohua; Liang, Yingqing; Zhang, Mingjie; Chen, Jibing; Lin, Mao
2017-01-01
In the present study, we aimed to compare the clinical outcome of autogeneic and allogeneic natural killer (NK) cells immunotherapy for the treatment of recurrent breast cancer. Between July 2016 and February 2017, 36 patients who met the enrollment criteria were randomly assigned to two groups: autogeneic NK cells immunotherapy group (group I, n=18) and allogeneic NK cells immunotherapy group (group II, n=18). The clinical efficacy, quality of life, immune function, circulating tumor cell (CTC) level, and other related indicators were evaluated. We found that allogeneic NK cells immunotherapy has better clinical efficacy than autogeneic therapy. Moreover, allogeneic NK cells therapy improves the quality of life, reduces the number of CTCs, reduces carcinoembryonic antigen and cancer antigen 15-3 (CA15-3) expression, and significantly enhances immune function. To our knowledge, this is the first clinical trial to compare the clinical outcome of autogeneic and allogeneic NK cells immunotherapy for recurrent breast cancer. PMID:28894383
Ben Ya'acov, Ami; Meir, Hadar; Zolotaryova, Lydia; Ilan, Yaron; Shteyer, Eyal
2017-03-23
It has been shown that the proportion of natural killer T cells is markedly elevated during liver regeneration and their activation under different conditions can modulate this process. As natural killer T cells and liver injury are central in liver regeneration, elucidating their role is important. The aim of the current study is to explore the role of natural killer T cells in impaired liver regeneration. Concanvalin A was injected 4 days before partial hepatectomy to natural killer T cells- deficient mice or to anti CD1d1-treated mice. Ki-67 and proliferating cell nuclear antigen were used to measure hepatocytes proliferation. Expression of hepatic cyclin B1 and proliferating cell nuclear antigen were evaluated by Western Blot and liver injury was assessed by ALT and histology. Natural killer T cells- deficient or mice injected with anti CD1d antibodies exhibited reduced liver regeneration. These mice were considerably resistant to ConA-induced liver injury. In the absence of NKT cells hepatic proliferating cell nuclear antigen and cyclin B1 decreased in mice injected with Concanvalin A before partial hepatectomy. This was accompanied with reduced serum interleukin-6 levels. Natural killer T cells play an important role in liver regeneration, which is associated with cyclin B1 and interleukin-6.
Large-Scale Culture and Genetic Modification of Human Natural Killer Cells for Cellular Therapy.
Lapteva, Natalia; Parihar, Robin; Rollins, Lisa A; Gee, Adrian P; Rooney, Cliona M
2016-01-01
Recent advances in methods for the ex vivo expansion of human natural killer (NK) cells have facilitated the use of these powerful immune cells in clinical protocols. Further, the ability to genetically modify primary human NK cells following rapid expansion allows targeting and enhancement of their immune function. We have successfully adapted an expansion method for primary NK cells from peripheral blood mononuclear cells or from apheresis products in gas permeable rapid expansion devices (G-Rexes). Here, we describe an optimized protocol for rapid and robust NK cell expansion as well as a method for highly efficient retroviral transduction of these ex vivo expanded cells. These methodologies are good manufacturing practice (GMP) compliant and could be used for clinical-grade product manufacturing.
Building tolerance by dismantling synapses: inhibitory receptor signaling in natural killer cells.
Huse, Morgan; Catherine Milanoski, S; Abeyweera, Thushara P
2013-01-01
Cell surface receptors bearing immunotyrosine-based inhibitory motifs (ITIMs) maintain natural killer (NK) cell tolerance to normal host tissues. These receptors are difficult to analyze mechanistically because they block activating responses in a rapid and comprehensive manner. The advent of high-resolution single cell imaging techniques has enabled investigators to explore the cell biological basis of the inhibitory response. Recent studies using these approaches indicate that ITIM-containing receptors function at least in part by structurally undermining the immunological synapse between the NK cell and its target. In this review, we discuss these new advances and how they might relate to what is known about the biochemistry of inhibitory signaling in NK cells and other cell types. © 2012 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.
Nguyen-Pham, Thanh-Nhan; Im, Chang-Min; Nguyen, Truc-Anh Thi; Lim, Mi-Seon; Hong, Cheol Yi; Kim, Mi-Hyun; Lee, Hyun Ju; Lee, Youn-Kyung; Cho, Duck; Ahn, Jae-Sook; Yang, Deok-Hwan; Kim, Yeo-Kyeoung; Chung, Ik-Joo; Kim, Hyeoung-Joon; Lee, Je-Jung
2011-09-01
The interaction between dendritic cells (DCs) and natural killer (NK) cells plays a key role in inducing DC maturation for subsequent T-cell priming. We investigated to generate potent DCs by stimulated with NK cells to induce myeloma-specific cytotoxic T lymphocytes (CTLs). NK cells-stimulated-DCs exhibited high expression of costimulatory molecules and high production of IL-12p70. These DCs induce high potency of Th1 polarization and exhibit a high ability to generate myeloma-specific CTLs responses. These results suggest that functionally potent DCs can be generated by stimulation with NK cells and may provide an effective source of DC-based immunotherapy in multiple myeloma. Copyright © 2011 Elsevier Ltd. All rights reserved.
Bosma, Anneleen; Abdel-Gadir, Azza; Isenberg, David A.; Jury, Elizabeth C.; Mauri, Claudia
2012-01-01
Summary B cells perform many immunological functions, including presenting lipid antigen to CD1d-restricted invariant natural killer T (iNKT) cells, known to contribute to maintaining tolerance in autoimmunity. Patients with systemic lupus erythematous (SLE) display dysregulated B cell responses and reduced peripheral iNKT cell frequencies. The significance of these defects and how they relate to SLE pathogenesis remain elusive. We report that B cells are essential for iNKT cell expansion and activation in healthy donors but fail to exert a similar effect in SLE patients. Defective B cell-mediated stimulation of iNKT cells in SLE patients was associated with altered CD1d recycling, a defect recapitulated in B cells from healthy donors after stimulation with interferon-α (IFN-α) and anti-immunoglobulin (Ig). iNKT cell number and function were restored in SLE patients responding to anti-CD20 treatment upon normalization of CD1d expression exclusively in repopulated immature B cells. We propose that healthy B cells are pivotal for iNKT cell homeostasis. PMID:22406267
Serum supplementation modulates the effects of dibutyltin on human natural killer cell function
NK cells are a subset of lymphocytes capable of killing tumor cells, virally infected cells and antibody coated cells. Dibutyltin dichloride (DBT) is an organotin used as a stabilizer in polyvinyl chloride (PVC) plastics and as a deworming product in poultry. DBT may leach from P...
Hurd-Brown, Tasia; Udoji, Felicia; Martin, Tamara; Whalen, Margaret M.
2012-01-01
1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) and triclosan (TCS) are organochlorine (OC) compounds that contaminate the environment, are found in human blood, and have been shown to decrease the tumor-cell killing (lytic) function of human natural killer (NK) cells. NK cells defend against tumor cells and virally infected cells. They bind to these targets, utilizing a variety of cell surface proteins. This study examined concentrations of DDT and TCS that decrease lytic function for alteration of NK binding to tumor targets. Levels of either compound that caused loss of binding function were then examined for effects on expression of cell-surface proteins needed for binding. NK cells exposed to 2.5 μM DDT for 24 h (which caused a greater than 55% loss of lytic function) showed a decrease in NK binding function of about 22%, and a decrease in CD16 cell-surface protein of 20%. NK cells exposed to 5 μM TCS for 24 h showed a decrease in ability to bind tumor cells of 37% and a decrease in expression of CD56 of about 34%. This same treatment caused a decrease in lytic function of greater than 87%. These results indicated that only a portion of the loss of NK lytic function seen with exposures to these compounds could be accounted for by loss of binding function. They also showed that loss of binding function is accompanied by a loss cell-surface proteins important in binding function. PMID:22729613
Rajalingam, Raja
2016-01-01
Natural killer (NK) cells of the innate immune system are cytotoxic lymphocytes that play an important roles following transplantation of solid organs and hematopoietic stem cells. Recognition of self-human leukocyte antigen (HLA) class I molecules by inhibitory killer cell immunoglobulin-like receptors (KIRs) is involved in the calibration of NK cell effector capacities during the developmental stage, allowing the subsequent recognition and elimination of target cells with decreased expression of self-HLA class I (due to virus infection or tumor transformation) or HLA class I disparities (in the setting of allogeneic transplantation). NK cells expressing an inhibitory KIR-binding self-HLA can be activated when confronted with allografts lacking a ligand for the inhibitory receptor. Following the response of the adaptive immune system, NK cells can further destroy allograft endothelium by antibody-dependent cell-mediated cytotoxicity (ADCC), triggered through cross-linking of the CD16 Fc receptor by donor-specific antibodies bound to allograft. Upon recognizing allogeneic target cells, NK cells also secrete cytokines and chemokines that drive maturation of dendritic cells to promote cellular and humoral adaptive immune responses against the allograft. The cumulative activating and inhibitory signals generated by ligation of the receptors regulates mature NK cell killing of target cells and their production of cytokines and chemokines. This review summarizes the role of NK cells in allograft rejection and proposes mechanistic concepts that indicate a prominent role for KIR–HLA interactions in facilitating NK cells for Fc receptor-mediated ADCC effector function involved in antibody-mediated rejection of solid organ transplants. PMID:28066408
IL-15 super-agonist (ALT-803) enhances natural killer (NK) cell function against ovarian cancer
Felices, M.; Chu, S.; Kodal, B.; Bendzick, L.; Ryan, C.; Lenvik, A.J.; Boylan, K.L.M.; Wong, H.C.; Skubitz, A.P.N.; Miller, J.S.; Geller, M.A.
2017-01-01
Objective Natural killer (NK) cells represent a powerful immunotherapeutic target as they lyse tumors directly, do not require differentiation, and can elicit potent inflammatory responses. The objective of these studies was to use an IL-15 super-agonist complex, ALT-803 (Altor BioScience Corporation), to enhance the function of both normal and ovarian cancer patient derived NK cells by increasing cytotoxicity and cytokine production. Methods NK cell function from normal donor peripheral blood mononuclear cells (PBMCs) and ovarian cancer patient ascites was assessed using flow cytometry and chromium release assays +/− ALT-803 stimulation. To evaluate the ability of ALT-803 to enhance NK cell function in vivo against ovarian cancer, we used a MA148-luc ovarian cancer NOD scid gamma (NSG) xenogeneic mouse model with transferred human NK cells. Results ALT-803 potently enhanced functionality of NK cells against all ovarian cancer cell lines with significant increases seen in CD107a, IFNγ and TNFα expression depending on target cell line. Function was also rescued in NK cells derived from ovarian cancer patient ascites. Finally, only animals treated with intraperitoneal ALT-803 displayed an NK dependent significant decrease in tumor. Conclusions ALT-803 enhances NK cell cytotoxicity against ovarian cancer in vitro and in vivo and is able to rescue functionality of NK cells derived from ovarian cancer patient ascites. These findings suggest that ALT-803 has the potential to enhance NK-cell-based immunotherapeutic approaches for the treatment of ovarian cancer. PMID:28236454
Kim, Choon Kwan; Choi, Youn Mi; Bae, Eunsin; Jue, Mihn Sook; So, Hyung Seok; Hwang, Eung-Soo
2018-01-01
The pathogenesis of herpes zoster is closely linked to reduced varicella-zoster virus-specific cell-mediated immunity. However, little is known about the interplay between natural killer cells and psychological stress in the pathogenesis of herpes zoster. This study aimed to investigate possible associations among natural killer cells, T cells and psychological stress in herpes zoster. Interferon-gamma secretion from natural killer cell, psychological stress events, stress cognition scale scores and cytomegalovirus-specific cell-mediated immunity were compared between 44 patients with herpes zoster and 44 age- and gender-matched control subjects. A significantly lower median level of interferon-gamma secreted by natural killer cells was observed in patients with a recent diagnosis of herpes zoster than in control subjects (582.7 pg/ml vs. 1783 pg/ml; P = 0.004), whereas cytomegalovirus-specific cell-mediated immunity was not associated with herpes zoster. Psychological stress events and high stress cognition scale scores were significantly associated in patients with herpes zoster (P<0.001 and P = 0.037, respectively). However, reduced interferon-gamma secretion from natural killer cell and psychological stress were not associated. In conclusion, patients with a recent diagnosis of herpes zoster display reduced interferon-gamma secretion from natural killer cells and frequent previous psychological stress events compared with controls. However, reduced natural killer cell activity is not an immunological mediator between psychological stress and herpes zoster.
Kim, Choon Kwan; Choi, Youn Mi; Bae, Eunsin; Jue, Mihn Sook; So, Hyung Seok
2018-01-01
The pathogenesis of herpes zoster is closely linked to reduced varicella-zoster virus-specific cell-mediated immunity. However, little is known about the interplay between natural killer cells and psychological stress in the pathogenesis of herpes zoster. This study aimed to investigate possible associations among natural killer cells, T cells and psychological stress in herpes zoster. Interferon-gamma secretion from natural killer cell, psychological stress events, stress cognition scale scores and cytomegalovirus-specific cell-mediated immunity were compared between 44 patients with herpes zoster and 44 age- and gender-matched control subjects. A significantly lower median level of interferon-gamma secreted by natural killer cells was observed in patients with a recent diagnosis of herpes zoster than in control subjects (582.7 pg/ml vs. 1783 pg/ml; P = 0.004), whereas cytomegalovirus-specific cell-mediated immunity was not associated with herpes zoster. Psychological stress events and high stress cognition scale scores were significantly associated in patients with herpes zoster (P<0.001 and P = 0.037, respectively). However, reduced interferon-gamma secretion from natural killer cell and psychological stress were not associated. In conclusion, patients with a recent diagnosis of herpes zoster display reduced interferon-gamma secretion from natural killer cells and frequent previous psychological stress events compared with controls. However, reduced natural killer cell activity is not an immunological mediator between psychological stress and herpes zoster. PMID:29466462
Immunomodulatory effects of aged garlic extract.
Kyo, E; Uda, N; Kasuga, S; Itakura, Y
2001-03-01
Using various kinds of models, we examined the effects of aged garlic extract (AGE) on immune functions. In the immunoglobulin (Ig)E-mediated allergic mouse model, AGE significantly decreased the antigen-specific ear swelling induced by picryl chloride ointment to the ear and intravenous administration of antitrinitrophenyl antibody. In the transplanted carcinoma cell model, AGE significantly inhibited the growth of Sarcoma-180 (allogenic) and LL/2 lung carcinoma (syngenic) cells transplanted into mice. Concomitantly, increases in natural killer (NK) and killer activities of spleen cells were observed in Sarcoma-180--bearing mice administered AGE. In the psychological stress model, AGE significantly prevented the decrease in spleen weight and restored the reduction of anti-SRBC hemolytic plaque-forming cells caused by the electrical stress. These studies strongly suggest that AGE could be a promising candidate as an immune modifier, which maintains the homeostasis of immune functions; further studies are warranted to determine when it is most beneficial.
Jia, Wei; Feng, Jie; Zhang, Jing-Song; Lin, Chi-Chung; Wang, Wen-Han; Chen, Hong-Ge
2017-01-01
FVPA1, a novel polysaccharide, has been isolated from fruiting bodies of the culinary-medicinal mushroom Flammulina velutipes, a historically popular, widely cultivated and consumed functional food with an attractive taste, beneficial nutraceutical properties such as antitumor and immunomodulatory effects, and a number of essential biological activities. The average molecular weight was estimated to be ~1.8 × 104 Da based on high-performance size exclusion chromatography. Sugar analyses, methylation analyses, and 1H, 13C, and 2-dimensional nuclear magnetic resonance spectroscopy revealed the following structure of the repeating units of the FVPA1 polysaccharide Identification of this structure would conceivably lead to better understanding of the nutraceutical functions of this very important edible fungus. Bioactivity tests in vitro indicated that FVPA1 could significantly enhance natural killer cell activity against K562 tumor cells.
Seidel, Ursula J. E.; Schlegel, Patrick; Lang, Peter
2013-01-01
In the last decade several therapeutic antibodies have been Federal Drug Administration (FDA) and European Medicines Agency (EMEA) approved. Although their mechanisms of action in vivo is not fully elucidated, antibody-dependent cellular cytotoxicity (ADCC) mediated by natural killer (NK) cells is presumed to be a key effector function. A substantial role of ADCC has been demonstrated in vitro and in mouse tumor models. However, a direct in vivo effect of ADCC in tumor reactivity in humans remains to be shown. Several studies revealed a predictive value of FcγRIIIa-V158F polymorphism in monoclonal antibody treatment, indicating a potential effect of ADCC on outcome for certain indications. Furthermore, the use of therapeutic antibodies after allogeneic hematopoietic stem cell transplantation is an interesting option. Studying the role of the FcγRIIIa-V158F polymorphism and the influence of Killer-cell Immunoglobuline-like Receptor (KIR) receptor ligand incompatibility on ADCC in this approach may contribute to future transplantation strategies. Despite the success of approved second-generation antibodies in the treatment of several malignancies, efforts are made to further augment ADCC in vivo by antibody engineering. Here, we review currently used therapeutic antibodies for which ADCC has been suggested as effector function. PMID:23543707
Biology and function of adipose tissue macrophages, dendritic cells and B cells.
Ivanov, Stoyan; Merlin, Johanna; Lee, Man Kit Sam; Murphy, Andrew J; Guinamard, Rodolphe R
2018-04-01
The increasing incidence of obesity and its socio-economical impact is a global health issue due to its associated co-morbidities, namely diabetes and cardiovascular disease [1-5]. Obesity is characterized by an increase in adipose tissue, which promotes the recruitment of immune cells resulting in low-grade inflammation and dysfunctional metabolism. Macrophages are the most abundant immune cells in the adipose tissue of mice and humans. The adipose tissue also contains other myeloid cells (dendritic cells (DC) and neutrophils) and to a lesser extent lymphocyte populations, including T cells, B cells, Natural Killer (NK) and Natural Killer T (NKT) cells. While the majority of studies have linked adipose tissue macrophages (ATM) to the development of low-grade inflammation and co-morbidities associated with obesity, emerging evidence suggests for a role of other immune cells within the adipose tissue that may act in part by supporting macrophage homeostasis. In this review, we summarize the current knowledge of the functions ATMs, DCs and B cells possess during steady-state and obesity. Copyright © 2018 Elsevier B.V. All rights reserved.
Lee, Ayoung; Lee, Young Ju; Yoo, Hye Jin; Kim, Minkyung; Chang, Yeeun; Lee, Dong Seog; Lee, Jong Ho
2017-05-31
The aim of this study was to investigate the impact of consuming dairy yogurt containing Lactobacillus paracasei ssp. paracasei ( L. paracasei ), Bifidobacterium animalis ssp. lactis ( B. lactis ) and heat-treated Lactobacillus plantarum ( L. plantarum ) on immune function. A randomized, open-label, placebo-controlled study was conducted on 200 nondiabetic subjects. Over a twelve-week period, the test group consumed dairy yogurt containing probiotics each day, whereas the placebo group consumed milk. Natural killer (NK) cell activity, interleukin (IL)-12 and immunoglobulin (Ig) G1 levels were significantly increased in the test group at twelve weeks compared to baseline. Additionally, the test group had significantly greater increases in serum NK cell activity and interferon (IFN)-γ and IgG1 than placebo group. Daily consumption of dairy yogurt containing L. paracasei , B. lactis and heat-treated L. plantarum could be an effective option to improve immune function by enhancing NK cell function and IFN-γ concentration (ClinicalTrials.gov: NCT03051425).
Lee, Ayoung; Lee, Young Ju; Yoo, Hye Jin; Kim, Minkyung; Chang, Yeeun; Lee, Dong Seog; Lee, Jong Ho
2017-01-01
The aim of this study was to investigate the impact of consuming dairy yogurt containing Lactobacillus paracasei ssp. paracasei (L. paracasei), Bifidobacterium animalis ssp. lactis (B. lactis) and heat-treated Lactobacillus plantarum (L. plantarum) on immune function. A randomized, open-label, placebo-controlled study was conducted on 200 nondiabetic subjects. Over a twelve-week period, the test group consumed dairy yogurt containing probiotics each day, whereas the placebo group consumed milk. Natural killer (NK) cell activity, interleukin (IL)-12 and immunoglobulin (Ig) G1 levels were significantly increased in the test group at twelve weeks compared to baseline. Additionally, the test group had significantly greater increases in serum NK cell activity and interferon (IFN)-γ and IgG1 than placebo group. Daily consumption of dairy yogurt containing L. paracasei, B. lactis and heat-treated L. plantarum could be an effective option to improve immune function by enhancing NK cell function and IFN-γ concentration (ClinicalTrials.gov: NCT03051425). PMID:28561762
The role of natural killer cells in chronic myeloid leukemia
Danier, Anna Carolyna Araújo; de Melo, Ricardo Pereira; Napimoga, Marcelo Henrique; Laguna-Abreu, Maria Theresa Cerávolo
2011-01-01
Chronic myeloid leukemia is a neoplasia resulting from a translocation between chromosomes 9 and 22 producing the BCR-ABL hybrid known as the Philadelphia chromosome (Ph). In chronic myeloid leukemia a proliferation of malignant myeloid cells occurs in the bone marrow due to excessive tyrosine kinase activity. In order to maintain homeostasis, natural killer cells, by means of receptors, identify the major histocompatibility complex on the surface of tumor cells and subsequently induce apoptosis. The NKG2D receptor in the natural killer cells recognizes the transmembrane proteins related to major histocompatibility complex class I chain-related genes A and B (MICA and MICB), and it is by the interaction between NKG2D and MICA that natural killer cells exert cytotoxic activity against chronic myeloid leukemia tumor cells. However, in the case of chronic exposure of the NKG2D receptor, the MICA ligand releases soluble proteins called sMICA from the tumor cell surface, which negatively modulate NKG2D and enable the tumor cells to avoid lysis mediated by the natural killer cells. Blocking the formation of sMICA may be an important antitumor strategy. Treatment using tyrosine kinase inhibitors induces modulation of NKG2DL expression, which could favor the activity of the natural killer cells. However this mechanism has not been fully described in chronic myeloid leukemia. In the present study, we analyze the role of natural killer cells to reduce proliferation and in the cellular death of tumor cells in chronic myeloid leukemia. PMID:23049299
The natural cytotoxicity in cosmonauts on board space stations
NASA Astrophysics Data System (ADS)
Meshkov, D.; Rykova, M.
The nature of the changes of resistance to infection seems to be very important. Our studies indicate that different functions of natural killers could be depressed after the spaceflight. The decrease of the percentage of the lymphocytes that can bind target cells lead to the lowering of the "active" NK level and this can be resulted in the depression of total NK activity and lowering of resistance to viral and tumor antigens. The investigation of natural killer cells in cosmonauts before and after short and long-term spaceflights also revealed the important role of spaceflight duration, stress and individual immune reactivity.
Natural Killer Cells Promote Fetal Development through the Secretion of Growth-Promoting Factors.
Fu, Binqing; Zhou, Yonggang; Ni, Xiang; Tong, Xianhong; Xu, Xiuxiu; Dong, Zhongjun; Sun, Rui; Tian, Zhigang; Wei, Haiming
2017-12-19
Natural killer (NK) cells are present in large populations at the maternal-fetal interface during early pregnancy. However, the role of NK cells in fetal growth is unclear. Here, we have identified a CD49a + Eomes + subset of NK cells that secreted growth-promoting factors (GPFs), including pleiotrophin and osteoglycin, in both humans and mice. The crosstalk between HLA-G and ILT2 served as a stimulus for GPF-secreting function of this NK cell subset. Decreases in this GPF-secreting NK cell subset impaired fetal development, resulting in fetal growth restriction. The transcription factor Nfil3, but not T-bet, affected the function and the number of this decidual NK cell subset. Adoptive transfer of induced CD49a + Eomes + NK cells reversed impaired fetal growth and rebuilt an appropriate local microenvironment. These findings reveal properties of NK cells in promoting fetal growth. In addition, this research proposes approaches for therapeutic administration of NK cells in order to reverse restricted nourishments within the uterine microenvironment during early pregnancy. Copyright © 2017 Elsevier Inc. All rights reserved.
Chang, Heng-Kwei
2015-01-01
Retinoic acid (RA), an active metabolite converted from vitamin A, plays an active role in immune function, such as defending against infections and immune regulation. Although RA affects various types of immune cells, including antigen-presenting cells, B lymphocytes, and T lymphocytes, whether it affects natural killer T (NKT) cells remain unknown. In this study, we found that RA decreased interferon (IFN)-γ production by activated NKT cells through T-cell receptor (TCR) and CD28. We also found that RA reduced extracellular signal-regulated kinase (ERK) phosphorylation, but increased phosphatase 2A (PP2A) activity in TCR/CD28-stimulated NKT cells. The increased PP2A activity, at least partly, contributed to the reduction of ERK phosphorylation. Since inhibition of ERK activation decreases IFN-γ production by TCR/CD28-stimulated NKT cells, RA may downregulate IFN-γ production by TCR/CD28-stimulated NKT cells through the PP2A-ERK pathway. Our results demonstrated a novel function of RA in modulating the IFN-γ expression by activated NKT cells. PMID:25343668
[Nasal type natural killer/T cell lymphoma: case series and literature review].
Düzlü, Mehmet; Ant, Ayça; Tutar, Hakan; Karamert, Recep; Şahin, Melih; Sayar, Erolcan; Cesur, Nesibe
2016-01-01
Nasal type natural killer/T-cell lymphoma is a rare type of extranodal non-Hodgkin lymphoma which originates from nasal cavity and paranasal sinuses. Exact diagnosis of nasal natural killer/T-cell lymphoma, which is a rapidly progressive clinical condition, may be established by immunohistochemical analysis on biopsy material after clinical suspicion. In this article, we report four cases of nasal natural killer/T-cell lymphoma who were followed-up in our clinic and discuss the diagnosis and treatment of the disease in light of the literature data.
Sha, Wei Hong; Zeng, Xiao Hui; Min, Lu
2014-05-01
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. 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. 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. 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.
Leveraging natural killer cells for cancer immunotherapy.
Grossenbacher, Steven K; Aguilar, Ethan G; Murphy, William J
2017-05-01
Natural killer (NK) cells are potent antitumor effector cells of the innate immune system. Based on their ability to eradicate tumors in vitro and in animal models, significant enthusiasm surrounds the prospect of leveraging human NK cells as vehicles for cancer immunotherapy. While interest in manipulating the effector functions of NK cells has existed for over 30 years, there is renewed optimism for this approach today. Although T cells receive much of the clinical and preclinical attention when it comes to cancer immunotherapy, new strategies are utilizing adoptive NK-cell immunotherapy and monoclonal antibodies and engineered molecules which have been developed to specifically activate NK cells against tumors. Despite the numerous challenges associated with the preclinical and clinical development of NK cell-based therapies for cancer, NK cells possess many unique immunological properties and hold the potential to provide an effective means for cancer immunotherapy.
Natural killer cells in host defense against veterinary pathogens.
Shekhar, Sudhanshu; Yang, Xi
2015-11-15
Natural Killer (NK) cells constitute a major subset of innate lymphoid cells that do not express the T- and B-cell receptors and play an important role in antimicrobial defense. NK cells not only induce early and rapid innate immune responses, but also communicate with dendritic cells to shape the adaptive immunity, thus bridging innate and adaptive immunity. Although the functional biology of NK cells is well-documented in a variety of infections in humans and mice, their role in protecting domestic animals from infectious agents is only beginning to be understood. In this article, we summarize the current state of knowledge about the contribution of NK cells in pathogen defense in domestic animals, especially cattle and pigs. Understanding the immunobiology of NK cells will translate into strategies to manipulate these cells for preventive and therapeutic purposes. Copyright © 2015 Elsevier B.V. All rights reserved.
Laouar, Yasmina; Sutterwala, Fayyaz S; Gorelik, Leonid; Flavell, Richard A
2005-06-01
Interferon-gamma and interleukin 12 produced by the innate arm of the immune system are important regulators of T helper type 1 (T(H)1) cell development, but signals that negatively regulate their expression remain controversial. Here we show that transforming growth factor-beta (TGF-beta) controlled T(H)1 differentiation through the regulation of interferon-gamma produced by natural killer (NK) cells. Blockade of TGF-beta signaling in NK cells caused the accumulation of a large pool of NK cells secreting copious interferon-gamma, responsible for T(H)1 differentiation and protection from leishmania infection. In contrast, blockade of TGF-beta signaling in dendritic cells did not affect dendritic cell homeostasis or interleukin 12 production, thus indicating a previously undescribed demarcation of the function of TGF-beta in NK cells versus dendritic cells.
The Broad Spectrum of Human Natural Killer Cell Diversity.
Freud, Aharon G; Mundy-Bosse, Bethany L; Yu, Jianhua; Caligiuri, Michael A
2017-11-21
Natural killer (NK) cells provide protection against infectious pathogens and cancer. For decades it has been appreciated that two major NK cell subsets (CD56 bright and CD56 dim ) exist in humans and have distinct anatomical localization patterns, phenotypes, and functions in immunity. In light of this traditional NK cell dichotomy, it is now clear that the spectrum of human NK cell diversity is much broader than originally appreciated as a result of variegated surface receptor, intracellular signaling molecule, and transcription factor expression; tissue-specific imprinting; and foreign antigen exposure. The recent discoveries of tissue-resident NK cell developmental intermediates, non-NK innate lymphoid cells, and the capacity for NK cells to adapt and differentiate into long-lived memory cells has added further complexity to this field. Here we review our current understanding of the breadth and generation of human NK cell diversity. Copyright © 2017 Elsevier Inc. All rights reserved.
Guo, Yalin; Maillard, Ivan; Chakraborti, Sankhamala; Rothenberg, Ellen V.
2008-01-01
CBFβ is the non-DNA binding subunit of the core binding factors (CBFs). Mice with reduced CBFβ levels display profound, early defects in T-cell but not B-cell development. Here we show that CBFβ is also required at very early stages of natural killer (NK)–cell development. We also demonstrate that T-cell development aborts during specification, as the expression of Gata3 and Tcf7, which encode key regulators of T lineage specification, is substantially reduced, as are functional thymic progenitors. Constitutively active Notch or IL-7 signaling cannot restore T-cell expansion or differentiation of CBFβ insufficient cells, nor can overexpression of Runx1 or CBFβ overcome a lack of Notch signaling. Therefore, the ability of the prethymic cell to respond appropriately to Notch is dependent on CBFβ, and both signals converge to activate the T-cell developmental program. PMID:18390836
Natural Killer Cell Function and Dysfunction in Hepatitis C Virus Infection
Holder, Kayla A.; Russell, Rodney S.; Grant, Michael D.
2014-01-01
Viruses must continually adapt against dynamic innate and adaptive responses of the host immune system to establish chronic infection. Only a small minority (~20%) of those exposed to hepatitis C virus (HCV) spontaneously clear infection, leaving approximately 200 million people worldwide chronically infected with HCV. A number of recent research studies suggest that establishment and maintenance of chronic HCV infection involve natural killer (NK) cell dysfunction. This relationship is illustrated in vitro by disruption of typical NK cell responses including both cell-mediated cytotoxicity and cytokine production. Expression of a number of activating NK cell receptors in vivo is also affected in chronic HCV infection. Thus, direct in vivo and in vitro evidence of compromised NK function in chronic HCV infection in conjunction with significant epidemiological associations between the outcome of HCV infection and certain combinations of NK cell regulatory receptor and class I human histocompatibility linked antigen (HLA) genotypes indicate that NK cells are important in the immune response against HCV infection. In this review, we highlight evidence suggesting that selective impairment of NK cell activity is related to establishment of chronic HCV infection. PMID:25057504
Hodge, Greg; Mukaro, Violet; Holmes, Mark; Reynolds, Paul N; Hodge, Sandra
2013-02-01
Natural killer (NK) and natural killer T (NKT)-like cells represent a small but important proportion of effector lymphocytes that we have previously shown to be major sources of pro-inflammatory cytokines and granzymes. We hypothesized that these cells would be increased in the airway in chronic obstructive pulmonary disease (COPD), accompanied by reduced expression of the inhibitory receptor CD94 (Kp43) and increased expression of cytotoxic mediators granzyme B and perforin. We measured NK and NKT-like cells and their expression of CD94 in the blood of COPD patients (n = 71; 30 current and 41 ex-smokers), smokers (16) and healthy controls (25), and bronchoalveolar lavage fluid (BALF) from a cohort of subjects (19 controls, 12 smokers, 33 COPD). Activation was assessed by measuring CD69 in blood and the cytotoxic potential of NK cells by measuring granzymes A and B, and using a cytotoxicity assay in blood and BALF. In blood in COPD, there were no significant changes in the proportion of NK or NKT-like cells or expression of granzyme A or NK cytotoxic potential versus controls. There was, however, increased expression of granzyme B and decreased expression of CD94 by both cell types versus controls. The proportion of NK and NKT-like cells were increased in BALF in COPD, associated with increased NK cytotoxicity, increased expression of granzyme B and decreased expression of the inhibitory receptor CD94 by both cell types. Treatment strategies that target NK and NKT-like cells, their cytotoxicity and production of inflammatory mediators in the airway may improve COPD morbidity. © 2012 The Authors. Respirology © 2012 Asian Pacific Society of Respirology.
Therapeutic manipulation of natural killer (NK) T cells in autoimmunity: are we close to reality?
Simoni, Y; Diana, J; Ghazarian, L; Beaudoin, L; Lehuen, A
2013-01-01
T cells reactive to lipids and restricted by major histocompatibility complex (MHC) class I-like molecules represent more than 15% of all lymphocytes in human blood. This heterogeneous population of innate cells includes the invariant natural killer T cells (iNK T), type II NK T cells, CD1a,b,c-restricted T cells and mucosal-associated invariant T (MAIT) cells. These populations are implicated in cancer, infection and autoimmunity. In this review, we focus on the role of these cells in autoimmunity. We summarize data obtained in humans and preclinical models of autoimmune diseases such as primary biliary cirrhosis, type 1 diabetes, multiple sclerosis, systemic lupus erythematosus, rheumatoid arthritis, psoriasis and atherosclerosis. We also discuss the promise of NK T cell manipulations: restoration of function, specific activation, depletion and the relevance of these treatments to human autoimmune diseases. PMID:23199318
Faure-Dupuy, Suzanne; Lucifora, Julie; Durantel, David
2017-01-01
The hepatitis B virus (HBV) infects hepatocytes, which are the main cell type composing a human liver. However, the liver is enriched with immune cells, particularly innate cells (e.g., myeloid cells, natural killer and natural killer T-cells (NK/NKT), dendritic cells (DCs)), in resting condition. Hence, the study of the interaction between HBV and innate immune cells is instrumental to: (1) better understand the conditions of establishment and maintenance of HBV infections in this secondary lymphoid organ; (2) define the role of these innate immune cells in treatment failure and pathogenesis; and (3) design novel immune-therapeutic concepts based on the activation/restoration of innate cell functions and/or innate effectors. This review will summarize and discuss the current knowledge we have on this interplay between HBV and liver innate immunity. PMID:28452930
Immunotherapeutic strategies targeting Natural killer T cell responses in cancer
Shissler, Susannah C.; Bollino, Dominique R.; Tiper, Irina V.; Bates, Joshua; Derakhshandeh, Roshanak; Webb, Tonya J.
2017-01-01
Natural killer T (NKT) cells are a unique subset of lymphocytes that bridge the innate and adaptive immune system. NKT cells possess a classic αβ T-cell receptor (TCR) that is able to recognize self and foreign glycolipid antigens presented by the nonclassical class I major histocompatibility complex (MHC) molecule, CD1d. Type I NKT cells (referred to as invariant NKT cells) express a semi-invariant Vα14Jα18 TCR in mice and Vα24Jα18 TCR in humans. Type II NKT cells are CD1d-restricted T cells that express a more diverse set of TCR α chains. The two types of NKT cells often exert opposing effects especially in tumor immunity, where Type II cells generally suppress tumor immunity while Type I NKT cells can enhance antitumor immune responses. In this review, we focus on the role of NKT cells in cancer. We discuss their effector and suppressive functions, as well as describe preclinical and clinical studies utilizing therapeutic strategies focused on harnessing their potent anti-tumor effector functions, and conclude with a discussion on potential next steps for the utilization of NKT cell targeted therapies for the treatment of cancer. PMID:27393665
Memory-like Responses of Natural Killer Cells
Cooper, Megan A.; Yokoyama, Wayne M.
2010-01-01
Summary Natural killer (NK) cells are lymphocytes with the capacity to produce cytokines and kill target cells upon activation. NK cells have long been categorized as members of the innate immune system and as such have been thought to follow the ‘rules’ of innate immunity, including the principle that they have no immunologic memory, a property thought to be strictly limited to adaptive immunity. However, recent studies have suggested that NK cells have the capacity to alter their behavior based on prior activation. This property is analogous to adaptive immune memory; however, some NK cell memory-like functions are not strictly antigen-dependent and can be demonstrated following cytokine stimulation. Here we discuss the recent evidence that NK cells can exhibit properties of immunologic memory, focusing on the ability of cytokines to non-specifically induce memory-like NK cells with enhanced responses to restimulation. PMID:20536571
WANG, DONGDONG; SAGA, YASUSHI; MIZUKAMI, HIROAKI; SATO, NAOTO; NONAKA, HIROAKI; FUJIWARA, HIROYUKI; TAKEI, YUJI; MACHIDA, SHIZUO; TAKIKAWA, OSAMU; OZAWA, KEIYA; SUZUKI, MITSUAKI
2012-01-01
This study examined the role of the immunosuppressive enzyme indoleamine-2,3-dioxygenase (IDO) in ovarian cancer progression, and the possible application of this enzyme as a target for ovarian cancer therapy. We transfected a short hairpin RNA vector targeting IDO into the human ovarian cancer cell line SKOV-3, that constitutively expresses IDO and established an IDO downregulated cell line (SKOV-3/shIDO) to determine whether inhibition of IDO mediates the progression of ovarian cancer. IDO downregulation suppressed tumor growth and peritoneal dissemination in vivo, without influencing cancer cell growth. Moreover, IDO downregulation enhanced the sensitivity of cancer cells to natural killer (NK) cells in vitro, and promoted NK cell accumulation in the tumor stroma in vivo. These findings indicate that downregulation of IDO controls ovarian cancer progression by activating NK cells, suggesting IDO targeting as a potential therapy for ovarian cancer. PMID:22179492
AHR prevents human IL-1R1hi ILC3 differentiation to natural killer cells
Hughes, Tiffany; Briercheck, Edward L.; Freud, Aharon G.; Trotta, Rossana; McClory, Susan; Scoville, Steven D.; Keller, Karen; Deng, Youcai; Cole, Jordan; Harrison, Nicholas; Mao, Charlene; Zhang, Jianying; Benson, Don M.; Yu, Jianhua; Caligiuri, Michael A.
2014-01-01
SUMMARY Accumulating evidence indicates that human natural killer (NK) cells develop in secondary lymphoid tissue (SLT) through a so-called “stage 3” developmental intermediate minimally characterized by a CD34-CD117+CD94- immunophenotype that lacks mature NK cell function. This stage 3 population is heterogeneous, potentially composed of functionally distinct innate lymphoid cell (ILC) types that includes interleukin-1 receptor (IL-1R1) positive, IL-22-producing ILC3s. Whether human ILC3s are developmentally related to NK cells is a subject of ongoing investigation. Here we show that antagonism of the aryl hydrocarbon receptor (AHR) or silencing of AHR gene expression promotes differentiation of tonsillar IL-22-producing IL-1R1hi human ILC3s to CD56brightCD94+ IFN-gamma-producing cytolytic mature NK cells expressing eomesodermin (EOMES) and T-Box Protein 21 (TBX21 or TBET). Hence, AHR is a transcription factor that prevents human IL-1R1hi ILC3s from differentiating into NK cells. PMID:24953655
Kang, Seung-Ji; Jin, Hye-Mi; Cho, Young-Nan; Kim, Seong Eun; Kim, Uh Jin; Park, Kyung-Hwa; Jang, Hee-Chang; Jung, Sook-In; Kee, Seung-Jung; Park, Yong-Wook
2017-07-01
Natural killer (NK) cells are essential immune cells against several pathogens. Not much is known regarding the roll of NK cells in Orientia tsutsugamushi infection. Thus, this study aims to determine the level, function, and clinical relevance of NK cells in patients with scrub typhus. This study enrolled fifty-six scrub typhus patients and 56 health controls (HCs). The patients were divided into subgroups according to their disease severity. A flow cytometry measured NK cell level and function in peripheral blood. Circulating NK cell levels and CD69 expressions were significantly increased in scrub typhus patients. Increased NK cell levels reflected disease severity. In scrub typhus patients, tests showed their NK cells produced higher amounts of interferon (IFN)-γ after stimulation with interleukin (IL)-12 and IL-18 relative to those of HCs. Meanwhile, between scrub typhus patients and HCs, the cytotoxicity and degranulation of NK cells against K562 were comparable. CD69 expressions were recovered to the normal levels in the remission phase. This study shows that circulating NK cells are activated and numerically increased, and they produced more IFN-γ in scrub typhus patients.
Cho, Young-Nan; Kim, Seong Eun; Kim, Uh Jin; Park, Kyung-Hwa; Jang, Hee-Chang; Jung, Sook-In; Kee, Seung-Jung
2017-01-01
Background Natural killer (NK) cells are essential immune cells against several pathogens. Not much is known regarding the roll of NK cells in Orientia tsutsugamushi infection. Thus, this study aims to determine the level, function, and clinical relevance of NK cells in patients with scrub typhus. Methodology/Principal findings This study enrolled fifty-six scrub typhus patients and 56 health controls (HCs). The patients were divided into subgroups according to their disease severity. A flow cytometry measured NK cell level and function in peripheral blood. Circulating NK cell levels and CD69 expressions were significantly increased in scrub typhus patients. Increased NK cell levels reflected disease severity. In scrub typhus patients, tests showed their NK cells produced higher amounts of interferon (IFN)-γ after stimulation with interleukin (IL)-12 and IL-18 relative to those of HCs. Meanwhile, between scrub typhus patients and HCs, the cytotoxicity and degranulation of NK cells against K562 were comparable. CD69 expressions were recovered to the normal levels in the remission phase. Conclusions This study shows that circulating NK cells are activated and numerically increased, and they produced more IFN-γ in scrub typhus patients. PMID:28750012
Yan, Wenwen; Zhou, Lin; Wen, Siwan; Duan, Qianglin; Huang, Feifei; Tang, Yu; Liu, Xiaohong; Chai, Yongyan; Wang, Lemin
2015-01-01
To evaluate the activity of natural killer cells through their inhibitory and activating receptors and quantity in peripheral blood mononuclear cells extracted from patients with acute myocardial infarction, stable angina pectoris and the controls. 100 patients with myocardial infarction, 100 with stable angina, and 20 healthy volunteers were recruited into the study. 20 randomly chosen people per group were examined for the whole human genome microarray analysis to detect the gene expressions of all 40 inhibitory and activating natural killer cell receptors. Flow cytometry analysis was applied to all 200 patients to measure the quantity of natural killer cells. In myocardial infarction group, the mRNA expressions of six inhibitory receptors KIR2DL2, KIR3DL3, CD94, NKG2A, KLRB1, KLRG1, and eight activating receptors KIR2DS3, KIR2DS5, NKp30, NTB-A, CRACC, CD2, CD7 and CD96 were significantly down-regulated (P<0.05) compared with both angina patients and the controls. There was no statistical difference in receptor expressions between angina patients and control group. The quantity of natural killer cells was significantly decreased in both infarction and angina patients compared with normal range (P<0.001). The significant mRNAs down-regulation of several receptors in myocardial infarction group and reduction in the quantity of natural killer cells in both myocardial infarction and angina patients showed a quantitative loss and dysfunction of natural killer cells in myocardial infarction patients.
Dudimah, Fred D; Griffey, Denisha; Wang, Xiaofei; Whalen, Margaret M
2010-10-01
Natural killer (NK) cells destroy (lyse) tumor cells, virally infected cells, and antibody-coated cells. Previous studies indicated that exposure to the environmental contaminant tributyltin (TBT) decreases the lytic function of NK cells and activates mitogen-activated protein kinases (MAPK), including p44/42 (Aluoch and Whalen Toxicology 209:263-277, 2005). If activation of p44/42 is required for TBT-induced decreases of lytic function, then activation of p44/42 to similar extents by pharmacological agents such as phorbol 12-myristate 13-acetate (PMA) should mimic to some extent changes induced in NK cells with TBT exposures. NK cells were exposed to PMA concentrations between 0.25 and 10 nM for 10 min, 1 h, and 6 h before determining the lytic function ((51)Cr release assay) and phosphorylation state of MAPKs (Western blot). A 1-h exposure of NK cells to 5 nM PMA resulted in a loss of lytic function of 47%. Western blot analysis showed that a 1-h exposure to 5 nM PMA caused a sixfold increase in phospho-p44/42 levels. Previous studies showed a fivefold increase in phospho-p44/42 in response to a 1-h exposure to 300 nM TBT. Exposure to 300 nM TBT caused about a 40% decrease in lytic function. This study supports the hypothesis that p44/42 activation (as seen with TBT exposures) can cause a loss of NK-cell lytic function.
Dudimah, Fred D.; Griffey, Denisha; Wang, Xiaofei; Whalen, Margaret M.
2009-01-01
Natural Killer (NK) cells destroy (lyse) tumor cells, virally infected cells and antibody-coated cells. Previous studies indicated that exposure to the environmental contaminant tributyltin (TBT) decreases the lytic function of NK cells and activates mitogen activated protein kinases (MAPK), including p44/42 (Aluoch and Whalen, 2005). If activation of p44/42 is required for TBT-induced decreases of lytic function, then activation of p44/42 to similar extents by pharmacological agents such as Phorbol 12-myristate 13-acetate (PMA) should mimic to some extent changes induced in NK cells with TBT exposures. NK cells were exposed to PMA concentrations between 0.25 and 10 nM for 10 min, 1 h, and 6 h before determining the lytic function (51Cr release assay) and phosphorylation state of MAPKs (Western blot). A 1 h exposure of NK cells to 5 nM PMA resulted in a loss of lytic function of 47%. Western blot analysis showed that a 1 h exposure to 5 nM PMA caused a 6 fold increase in phospho-p44/42 levels. Previous studies showed a 5 fold increase in phospho-p44/42 in response to a 1 h exposure to 300 nM TBT. Exposure to 300 nM TBT caused about a 40% decrease in lytic function. This study supports the hypothesis that p44/42 activation (as seen with TBT exposures) can cause a loss of NK-cell lytic function. PMID:20213532
Mouse natural killer cell development and maturation are differentially regulated by SHIP-1.
Banh, Cindy; Miah, S M Shahjahan; Kerr, William G; Brossay, Laurent
2012-11-29
The SH2-containing inositol phosphatase-1 (SHIP-1) is a 5' inositol phosphatase known to negatively regulate the product of phosphoinositide-3 kinase (PI3K), phosphatidylinositol-3.4,5-trisphosphate. SHIP-1 can be recruited to a large number of inhibitory receptors expressed on natural killer (NK) cells. However, its role in NK cell development, maturation, and functions is not well defined. In this study, we found that the absence of SHIP-1 results in a loss of peripheral NK cells. However, using chimeric mice we demonstrated that SHIP-1 expression is not required intrinsically for NK cell lineage development. In contrast, SHIP-1 is required cell autonomously for NK cell terminal differentiation. These findings reveal both a direct and indirect role for SHIP-1 at different NK cell development checkpoints. Notably, SHIP-1-deficient NK cells display an impaired ability to secrete IFN-γ during cytokine receptor-mediated responses, whereas immunoreceptor tyrosine-based activation motif containing receptor-mediated responses is not affected. Taken together, our results provide novel insights on how SHIP-1 participates in the development, maturation, and effector functions of NK cells.
“Multi-Omics” Analyses of the Development and Function of Natural Killer Cells
Zhou, Yonggang; Xu, Xiuxiu; Tian, Zhigang; Wei, Haiming
2017-01-01
For over four decades, our understanding of natural killer (NK) cells has evolved from the original description of cluster of differentiation (CD)56+CD3− to establishing NK cells as an important subset of innate lymphocytes in the host’s surveillance against viral infections and malignancy. The progress of research on the fundamental properties and therapeutic prospects for translational medicine using NK cells excites immunologists and clinicians. Over the past decade, numerous advances in “-omics”-scale methods and new technological approaches have addressed many essential questions in the biology of NK cells. We now have further understanding of the overall molecular mechanisms of action that determine the development, function, plasticity, diversity, and immune reactivity of NK cells. These findings are summarized here, and our view on how to study NK cells using “multi-omics” is highlighted. We also describe “-omics” analyses of the relationships between NK cells and viral infection, tumorigenesis, and autoimmune diseases. Ultimately, a deeper and more comprehensive understanding of NK cells in multiple conditions will provide more effective strategies to manipulate NK cells for the treatment of human disease. PMID:28928751
Models to Study NK Cell Biology and Possible Clinical Application.
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. Copyright © 2015 John Wiley & Sons, Inc.
Rana, Niki; Cultrara, Christopher; Phillips, Mariana; Sabatino, David
2017-09-01
In the search for more potent peptide-based anti-cancer conjugates the generation of new, functionally diverse nucleolipid derived D-(KLAKLAK) 2 -AK sequences has enabled a structure and anti-cancer activity relationship study. A reductive amination approach was key for the synthesis of alkylamine, diamine and polyamine derived nucleolipids as well as those incorporating heterocyclic functionality. The carboxy-derived nucleolipids were then coupled to the C-terminus of the D-(KLAKLAK) 2 -AK killer peptide sequence and produced with and without the FITC fluorophore for investigating biological activity in cancer cells. The amphiphilic, α-helical peptide-nucleolipid bioconjugates were found to exhibit variable effects on the viability of MM.1S cells, with the histamine derived nucleolipid peptide bioconjugate displaying the most significant anti-cancer effects. Thus, functionally diverse nucleolipids have been developed to fine-tune the structure and anti-cancer properties of killer peptide sequences, such as D-(KLAKLAK) 2 -AK. Copyright © 2017 Elsevier Ltd. All rights reserved.
Pluripotent stem cell-derived natural killer cells for cancer therapy
Knorr, David A.; Kaufman, Dan S.
2010-01-01
Human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs) provide an accessible, genetically tractable and homogenous starting cell populations to efficiently study human blood cell development. These cell populations provide platforms to develop new cell-based therapies to treat both malignant and non-malignant hematological diseases. Our group has previously demonstrated the ability of hESC-derived hematopoietic precursors to produce functional natural killer (NK) cells as well as an explanation of the underlying mechanism responsible for inefficient development of T and B cells from hESCs. hESCs and iPSCs, which can be reliably engineered in vitro, provide an important new model system to study human lymphocyte development and produce enhanced cell-based therapies with potential to serve as a “universal” source of anti-tumor lymphocytes for novel clinical therapies. This review will focus on the application of hESC-derived NK cells with currently used and novel therapeutics for clinical trials, current barriers to translation, and future applications through genetic engineering approaches. PMID:20801411
Morikawa, Yuko; Kitaoka-Higashiguchi, Kazuyo; Tanimoto, Chie; Hayashi, Midori; Oketani, Reiko; Miura, Katsuyuki; Nishijo, Muneko; Nakagawa, Hideaki
2005-09-01
The present study investigated the effects of job stress on cellular immune function, such as NK cell activity and NK cell subsets. The participants were 61 female nurses aged 23-59, who worked in a public psychiatric hospital in Ishikawa, Japan. Each subject completed the Nursing Job Stressor Scale (NJSS) and their NK cell activity and lymphocyte surface antigens (CD16+56+) were evaluated as immune system parameters. The NJSS has seven subscales: conflict with other nursing staff, nursing role conflict, conflict with physicians or autonomy, conflict with death or dying, quantitative work load, qualitative work load and conflict with patients. Factors influencing NK cell activity, and the proportion and cell counts of CD16+56+ lymphocytes were evaluated. Increase in quantitative work load significantly decreased NK cell activity. Conversely, no linear relationship was observed between qualitative work load and immunological variables, with the highest percentage of CD16+56+ lymphocytes observed among participants in the medium work load group. The other five NJSS subscales did not relate to immune parameters. In conclusion, the results suggest that perceived job strains, particularly quantitative work load, decreased NK cell function.
NK cell-released exosomes: Natural nanobullets against tumors.
Fais, Stefano
2013-01-01
We have recently reported that human natural killer (NK) cells release exosomes that express both NK-cell markers and cytotoxic molecules. Similar results were obtained with circulating exosomes from human healthy donors. Both NK-cell derived and circulating exosomes exerted a full functional activity and killed both tumor and activated immune cells. These findings indicate that NK-cell derived exosomes might constitute a new promising therapeutic tool.
Fais, Stefano
2013-01-01
We have recently reported that human natural killer (NK) cells release exosomes that express both NK-cell markers and cytotoxic molecules. Similar results were obtained with circulating exosomes from human healthy donors. Both NK-cell derived and circulating exosomes exerted a full functional activity and killed both tumor and activated immune cells. These findings indicate that NK-cell derived exosomes might constitute a new promising therapeutic tool. PMID:23482694
Schmied, Laurent; Terszowski, Grzegorz; Gonzalez, Asensio; Schmitter, Karin; Hirsch, Hans H; Garzoni, Christian; van Delden, Christian; Boggian, Katia; Mueller, Nicolas J; Berger, Christoph; Villard, Jean; Manuel, Oriol; Meylan, Pascal; Hess, Christoph; Stern, Martin
2015-12-01
Natural killer cell function is regulated by inhibitory and activating killer cell immunoglobulin-like receptors (KIR). Previous studies have documented associations of KIR genotype with the risk of cytomegalovirus (CMV) replication after solid organ transplantation. In this study of 649 solid organ transplant recipients, followed prospectively for infectious disease events within the Swiss Transplant Cohort Study, we were interested to see if KIR genotype associated with virus infections other than CMV. We found that KIR B haplotypes (which have previously been linked to protection from CMV replication) were associated with protection from varicella zoster virus infection (hazard ratio, 0.43; 95% confidence interval, 0.21-0.91; P = 0.03). No significant associations were detected regarding the risk of herpes simplex, Epstein-Barr virus or BK polyomavirus infections. In conclusion, these data provide evidence that the relative protection of KIR haplotype B from viral replication after solid organ transplantation may extend beyond CMV to other herpes viruses, such as varicella zoster virus and possibly Epstein-Barr virus.
Type II Natural Killer T (NKT) Cells And Their Emerging Role In Health And Disease
Dhodapkar, Madhav V.; Kumar, Vipin
2016-01-01
Natural killer T (NKT) cells recognize lipid antigens presented by a class I MHC-like molecule CD1d, a member of the CD1 family. While most of the initial studies on NKT cells focused on a subset with semi-invariant T cell receptor (TCR) termed iNKT cells, majority of CD1d-restricted lipid-reactive human T cells express diverse TCRs and are termed as type II NKT cells. These cells constitute a distinct population of circulating and tissue-resident effector T cells with immune-regulatory properties. They react to a growing list of self- as well as non-self lipid ligands, and share some properties with both iNKT as well as conventional T cells. Emerging body of evidence points to their role in the regulation of immunity to pathogens/tumors and in autoimmune/metabolic disorders. Improved understanding of the biology of these cells and the ability to manipulate their function may be of therapeutic benefit in diverse disease conditions. PMID:28115591
Raulet, David H; Marcus, Assaf; Coscoy, Laurent
2017-11-01
Natural killer (NK) cells recognize and kill cancer cells and infected cells by engaging cell surface ligands that are induced preferentially or exclusively on these cells. These ligands are recognized by activating receptors on NK cells, such as NKG2D. In addition to activation by cell surface ligands, the acquisition of optimal effector activity by NK cells is driven in vivo by cytokines and other signals. This review addresses a developing theme in NK cell biology: that NK-activating ligands on cells, and the provision of cytokines and other signals that drive high effector function in NK cells, are driven by abnormalities that arise from transformation or the infected state. The pathways include genomic damage, which causes self DNA to be exposed in the cytosol of affected cells, where it activates the DNA sensor cGAS. The resulting signaling induces NKG2D ligands and also mobilizes NK cell activation. Other key pathways that regulate NKG2D ligands include PI-3 kinase activation, histone acetylation, and the integrated stress response. This review summarizes the roles of these pathways and their relevance in both viral infections and cancer. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Jara, Claudia; Ibañez, Jorge; Ahumada, Viviana; Acuña-Castillo, Claudio; Martin, Adrian; Córdova, Alexandra
2016-01-01
Human Natural Killer (NK) cells are a specialized heterogeneous subpopulation of lymphocytes involved in antitumor defense reactions. NK cell effector functions are critically dependent on cytokines and metabolic activity. Among various cytokines modulating NK cell function, interleukin-2 (IL-2) can induce a more potent cytotoxic activity defined as lymphokine activated killer activity (LAK). Our aim was to determine if IL-2 induces changes at the mitochondrial level in NK cells to support the bioenergetic demand for performing this enhanced cytotoxic activity more efficiently. Purified human NK cells were cultured with high IL-2 concentrations to develop LAK activity, which was assessed by the ability of NK cells to lyse NK-resistant Daudi cells. Here we show that, after 72 h of culture of purified human NK cells with enough IL-2 to induce LAK activity, both the mitochondrial mass and the mitochondrial membrane potential increased in a PGC-1α-dependent manner. In addition, oligomycin, an inhibitor of ATP synthase, inhibited IL-2-induced LAK activity at 48 and 72 h of culture. Moreover, the secretion of IFN-γ from NK cells with LAK activity was also partially dependent on PGC-1α expression. These results indicate that PGC-1α plays a crucial role in regulating mitochondrial function involved in the maintenance of LAK activity in human NK cells stimulated with IL-2. PMID:27413259
Miranda, Dante; Jara, Claudia; Ibañez, Jorge; Ahumada, Viviana; Acuña-Castillo, Claudio; Martin, Adrian; Córdova, Alexandra; Montoya, Margarita
2016-01-01
Human Natural Killer (NK) cells are a specialized heterogeneous subpopulation of lymphocytes involved in antitumor defense reactions. NK cell effector functions are critically dependent on cytokines and metabolic activity. Among various cytokines modulating NK cell function, interleukin-2 (IL-2) can induce a more potent cytotoxic activity defined as lymphokine activated killer activity (LAK). Our aim was to determine if IL-2 induces changes at the mitochondrial level in NK cells to support the bioenergetic demand for performing this enhanced cytotoxic activity more efficiently. Purified human NK cells were cultured with high IL-2 concentrations to develop LAK activity, which was assessed by the ability of NK cells to lyse NK-resistant Daudi cells. Here we show that, after 72 h of culture of purified human NK cells with enough IL-2 to induce LAK activity, both the mitochondrial mass and the mitochondrial membrane potential increased in a PGC-1α-dependent manner. In addition, oligomycin, an inhibitor of ATP synthase, inhibited IL-2-induced LAK activity at 48 and 72 h of culture. Moreover, the secretion of IFN-γ from NK cells with LAK activity was also partially dependent on PGC-1α expression. These results indicate that PGC-1α plays a crucial role in regulating mitochondrial function involved in the maintenance of LAK activity in human NK cells stimulated with IL-2.
Improving efficacy of cancer immunotherapy by genetic modification of natural killer cells.
Burga, Rachel A; Nguyen, Tuongvan; Zulovich, Jane; Madonna, Sarah; Ylisastigui, Loyda; Fernandes, Rohan; Yvon, Eric
2016-11-01
Natural killer (NK) cells are members of the innate immune system that recognize target cells via activating and inhibitory signals received through cell receptors. Derived from the lymphoid lineage, NK cells are able to produce cytokines and exert a cytotoxic effect on viral infected and malignant cells. It is their unique ability to lyse target cells rapidly and without prior education that renders NK cells a promising effector cell for adoptive cell therapy. However, both viruses and tumors employ evasion strategies to avoid attack by NK cells, which represent biological challenges that need to be harnessed to fully exploit the cytolytic potential of NK cells. Using genetic modification, the function of NK cells can be enhanced to improve their homing, cytolytic activity, in vivo persistence and safety. Examples include gene modification to express chemokine, high-affinity Fc receptor and chimeric antigen receptors, suicide genes and the forced expression of cytokines such as interleukin (IL)-2 and IL-15. Preclinical studies have clearly demonstrated that such approaches are effective in improving NK-cell function, homing and safety. In this review, we summarize the recent advances in the genetic manipulations of NK cells and their application for cellular immunotherapeutic strategies. Copyright © 2016 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.
May, Rebecca M.; Okumura, Mariko; Hsu, Chin-Jung; Bassiri, Hamid; Yang, Enjun; Rak, Gregory; Mace, Emily M.; Philip, Naomi H.; Zhang, Weiguo; Baumgart, Tobias; Orange, Jordan S.; Nichols, Kim E.
2013-01-01
Signaling pathways leading to natural killer (NK)–cell effector function are complex and incompletely understood. Here, we investigated the proximal signaling pathways downstream of the immunotyrosine-based activation motif (ITAM) bearing activating receptors. We found that the adaptor molecule SH2 domain-containing leukocyte protein of 76 kD (SLP-76) is recruited to microclusters at the plasma membrane in activated NK cells and that this is required for initiation of downstream signaling and multiple NK-cell effector functions in vitro and in vivo. Surprisingly, we found that 2 types of proximal signaling complexes involving SLP-76 were formed. In addition to the canonical membrane complex formed between SLP-76 and linker for activation of T cells (LAT) family members, a novel LAT family–independent SLP-76–dependent signaling pathway was identified. The LAT family–independent pathway involved the SH2 domain of SLP-76 and adhesion and degranulation-promoting adaptor protein (ADAP). Both the LAT family–dependent and ADAP-dependent pathway contributed to interferon-gamma production and cytotoxicity; however, they were not essential for other SLP-76–dependent events, including phosphorylation of AKT and extracellular signal–related kinase and cellular proliferation. These results demonstrate that NK cells possess an unexpected bifurcation of proximal ITAM-mediated signaling, each involving SLP-76 and contributing to optimal NK-cell function. PMID:23407547
USDA-ARS?s Scientific Manuscript database
We have identified Severe Combined Immunodeficiency (SCID) in a line of Yorkshire pigs at Iowa State University. These SCID pigs lack B-cells and T-cells, but possess Natural Killer (NK) cells. This SCID phenotype is caused by recessive mutations in the Artemis gene. Interestingly, two human tumor c...
Sivori, Simona; Falco, Michela; Marcenaro, Emanuela; Parolini, Silvia; Biassoni, Roberto; Bottino, Cristina; Moretta, Lorenzo; Moretta, Alessandro
2002-01-01
In this study we analyzed the progression of cell surface receptor expression during the in vitro-induced human natural killer (NK) cell maturation from CD34+ Lin− cell precursors. NKp46 and NKp30, two major triggering receptors that play a central role in natural cytotoxicity, were expressed before the HLA class I-specific inhibitory receptors. Moreover, their appearance at the cell surface correlated with the acquisition of cytolytic activity by developing NK cells. Although the early expression of triggering receptors may provide activating signals required for inducing further cell differentiation, it may also affect the self-tolerance of developing NK cells. Our data show that a fail-safe mechanism preventing killing of normal autologous cells may be provided by the 2B4 surface molecule, which, at early stages of NK cell differentiation, functions as an inhibitory rather than as an activating receptor. PMID:11917118
USDA-ARS?s Scientific Manuscript database
We previously showed that dietary white button mushrooms (WBM) enhanced natural killer cell activity and that in vitro WBM supplementation promotes maturation and function of dendritic cells (DC). The current study investigated whether WBM consumption would enhance pathogen-specific immune response ...
Chieregato, Katia; Zanon, Cristina; Castegnaro, Silvia; Bernardi, Martina; Amati, Eliana; Sella, Sabrina; Rodeghiero, Francesco; Astori, Giuseppe
2017-01-01
Cytokine-induced killer cells are polyclonal T cells generated ex vivo and comprise two main subsets: the CD56- fraction, possessing an alloreactive potential caused by T cells (CD3+CD56-), and the CD56+ fraction, characterised by a strong antitumour capacity induced by natural killer-like T cells (NK-like T, CD3+CD56+) and natural killer cells (NK, CD3-CD56+ bright). We investigated the cytotoxic action of selected CD56+ cell subpopulations against a human chronic myeloid leukaemia (K562) cell line. After immunomagnetic selection of the CD56+ cell fraction, NK bright cells (CD3-CD56+ bright) and two subsets of NK-like T cells (CD3+CD56+), called NK-like T CD56 dim and NK-like T CD56 bright, could be identified. The cytotoxic effect against K562 cells was mainly exerted by the NK bright subpopulation and resulted to be inversely correlated with the percentage of NK-like T CD56 dim cells in the culture. The lytic action appeared to be independent of cell degranulation as suggested by the lack of change in the expression of CD107a. We conclude that the cytotoxic action of CD56+ cells against a K562 cell line is mainly due to the NK cells.
McGrath, Emma; Ryan, Elizabeth J; Lynch, Lydia; Golden-Mason, Lucy; Mooney, Eoghan; Eogan, Maeve; O'Herlihy, Colm; O'Farrelly, Cliona
2009-04-01
Cycle-dependent fluctuations in natural killer (NK) cell populations in endometrium and circulation may differ, contributing to unexplained infertility. NK cell phenotypes were determined by flow cytometry in endometrial biopsies and matched blood samples. While circulating and endometrial T cell populations remained constant throughout the menstrual cycle in fertile and infertile women, circulating NK cells in infertile women increased during the secretory phase. However, increased expression of CD94, CD158b (secretory phase), and CD158a (proliferative phase) by endometrial NK cells from infertile women was observed. These changes were not reflected in the circulation. In infertile women, changes in circulating NK cell percentages are found exclusively during the secretory phase and not in endometrium; cycle-related changes in NK receptor expression are observed only in infertile endometrium. While having exciting implications for understanding NK cell function in fertility, our data emphasize the difficulty in attaching diagnostic or prognostic significance to NK cell analyses in individual patients.
Ly49 Receptors: Innate and Adaptive Immune Paradigms
Rahim, Mir Munir A.; Tu, Megan M.; Mahmoud, Ahmad Bakur; Wight, Andrew; Abou-Samra, Elias; Lima, Patricia D. A.; Makrigiannis, Andrew P.
2014-01-01
The Ly49 receptors are type II C-type lectin-like membrane glycoproteins encoded by a family of highly polymorphic and polygenic genes within the mouse natural killer (NK) gene complex. This gene family is designated Klra, and includes genes that encode both inhibitory and activating Ly49 receptors in mice. Ly49 receptors recognize class I major histocompatibility complex-I (MHC-I) and MHC-I-like proteins on normal as well as altered cells. Their functional homologs in humans are the killer cell immunoglobulin-like receptors, which recognize HLA class I molecules as ligands. Classically, Ly49 receptors are described as being expressed on both the developing and mature NK cells. The inhibitory Ly49 receptors are involved in NK cell education, a process in which NK cells acquire function and tolerance toward cells that express “self-MHC-I.” On the other hand, the activating Ly49 receptors recognize altered cells expressing activating ligands. New evidence shows a broader Ly49 expression pattern on both innate and adaptive immune cells. Ly49 receptors have been described on multiple NK cell subsets, such as uterine NK and memory NK cells, as well as NKT cells, dendritic cells, plasmacytoid dendritic cells, macrophages, neutrophils, and cells of the adaptive immune system, such as activated T cells and regulatory CD8+ T cells. In this review, we discuss the expression pattern and proposed functions of Ly49 receptors on various immune cells and their contribution to immunity. PMID:24765094
Suppression of a Natural Killer Cell Response by Simian Immunodeficiency Virus Peptides
Schafer, Jamie L.; Ries, Moritz; Guha, Natasha; Connole, Michelle; Colantonio, Arnaud D.; Wiertz, Emmanuel J.; Wilson, Nancy A.; Kaur, Amitinder; Evans, David T.
2015-01-01
Natural killer (NK) cell responses in primates are regulated in part through interactions between two highly polymorphic molecules, the killer-cell immunoglobulin-like receptors (KIRs) on NK cells and their major histocompatibility complex (MHC) class I ligands on target cells. We previously reported that the binding of a common MHC class I molecule in the rhesus macaque, Mamu-A1*002, to the inhibitory receptor Mamu-KIR3DL05 is stabilized by certain simian immunodeficiency virus (SIV) peptides, but not by others. Here we investigated the functional implications of these interactions by testing SIV peptides bound by Mamu-A1*002 for the ability to modulate Mamu-KIR3DL05+ NK cell responses. Twenty-eight of 75 SIV peptides bound by Mamu-A1*002 suppressed the cytolytic activity of primary Mamu-KIR3DL05+ NK cells, including three immunodominant CD8+ T cell epitopes previously shown to stabilize Mamu-A1*002 tetramer binding to Mamu-KIR3DL05. Substitutions at C-terminal positions changed inhibitory peptides into disinhibitory peptides, and vice versa, without altering binding to Mamu-A1*002. The functional effects of these peptide variants on NK cell responses also corresponded to their effects on Mamu-A1*002 tetramer binding to Mamu-KIR3DL05. In assays with mixtures of inhibitory and disinhibitory peptides, low concentrations of inhibitory peptides dominated to suppress NK cell responses. Consistent with the inhibition of Mamu-KIR3DL05+ NK cells by viral epitopes presented by Mamu-A1*002, SIV replication was significantly higher in Mamu-A1*002+ CD4+ lymphocytes co-cultured with Mamu-KIR3DL05+ NK cells than with Mamu-KIR3DL05- NK cells. These results demonstrate that viral peptides can differentially affect NK cell responses by modulating MHC class I interactions with inhibitory KIRs, and provide a mechanism by which immunodeficiency viruses may evade NK cell responses. PMID:26333068
Cancer Immunology at the Crossroads: Killer immunoglobulin-like receptors and tumor immunity
Benson, Don M; Caligiuri, Michael A
2014-01-01
Natural killer (NK) cells, large granular lymphocytes comprising a key cellular subset of innate immunity, were originally named for their capacity to elicit potent cytotoxicity against tumor cells independent of prior sensitization or gene rearrangement. This process is facilitated through the expression of activating and inhibitory receptors that provide for NK cell “education” and a subsequent ability to survey, recognize and lyse infected or transformed cells, especially those lacking or possessing mutated major histocompatibility complex (MHC) class I expression. Since these original observations were made, how NK cells recognize candidate target cells continues to be the topic of ongoing investigation. It is now appreciated that NK cells express a diverse repertoire of activating and inhibitory receptors of which killer immunoglobulin-like receptors (KIR) appear to play a critical role in mediating self-tolerance as well as facilitating cytotoxicity against infected or transformed cells. Additionally, in the presence of an activating signal, the absence or mismatch of MHC class I molecules on such targets (which serve as inhibitory KIR ligands) promotes NK cell-mediated lysis. An increasing understanding of the complexities of KIR biology has provided recent opportunities to leverage the NK cell versus tumor effect as a novel avenue of therapeutic immunotherapy for cancer. The present review seeks to summarize the current understanding of KIR expression and function and highlight ongoing efforts to translate these discoveries into novel NK cell-mediated immunotherapies for cancer. PMID:24592397
Nguyen-Pham, Thanh-Nhan; Yang, Deok-Hwan; Nguyen, Truc-Anh Thi; Lim, Mi-Seon; Hong, Cheol Yi; Kim, Mi-Hyun; Lee, Hyun Ju; Lee, Youn-Kyung; Cho, Duck; Bae, Soo-Young; Ahn, Jae-Sook; Kim, Yeo-Kyeoung; Chung, Ik-Joo; Kim, Hyeoung-Joon; Lee, Je-Jung
2012-01-01
Dendritic cell (DC)-based vaccines continue to be considered an attractive tool for cancer immunotherapy. DCs require an additional signal from the environment or other immune cells to polarize the development of immune responses toward T helper 1 (Th1) or Th2 responses. DCs play a role in natural killer (NK) cell activation, and NK cells are also able to activate and induce the maturation of DCs. We investigated the types of NK cells that can induce the maturation and enhanced function of DCs and the conditions under which these interactions occur. DCs that were activated by resting NK cells in the presence of inflammatory cytokines exhibited increased expression of several costimulatory molecules and an enhanced ability to produce IL-12p70. NK cell-stimulated DCs potently induced Th1 polarization and exhibited the ability to generate tumor antigen-specific cytotoxic T lymphocyte responses. Our data demonstrate that functional DCs can be generated by coculturing immature DCs with freshly isolated resting NK cells in the presence of Toll-like receptor agonists and proinflammatory cytokines and that the resulting DCs effectively present antigens to induce tumor-specific T-cell responses, which suggests that these cells may be useful for cancer immunotherapy.
K2 killer toxin-induced physiological changes in the yeast Saccharomyces cerevisiae.
Orentaite, Irma; Poranen, Minna M; Oksanen, Hanna M; Daugelavicius, Rimantas; Bamford, Dennis H
2016-03-01
Saccharomyces cerevisiae cells produce killer toxins, such as K1, K2 and K28, that can modulate the growth of other yeasts giving advantage for the killer strains. Here we focused on the physiological changes induced by K2 toxin on a non-toxin-producing yeast strain as well as K1, K2 and K28 killer strains. Potentiometric measurements were adjusted to observe that K2 toxin immediately acts on the sensitive cells leading to membrane permeability. This correlated with reduced respiration activity, lowered intracellular ATP content and decrease in cell viability. However, we did not detect any significant ATP leakage from the cells treated by killer toxin K2. Strains producing heterologous toxins K1 and K28 were less sensitive to K2 than the non-toxin producing one suggesting partial cross-protection between the different killer systems. This phenomenon may be connected to the observed differences in respiratory activities of the killer strains and the non-toxin-producing strain at low pH. This might also have practical consequences in wine industry; both as beneficial ones in controlling contaminating yeasts and non-beneficial ones causing sluggish fermentation. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Sojka, Dorothy K; Plougastel-Douglas, Beatrice; Yang, Liping; Pak-Wittel, Melissa A; Artyomov, Maxim N; Ivanova, Yulia; Zhong, Chao; Chase, Julie M; Rothman, Paul B; Yu, Jenny; Riley, Joan K; Zhu, Jinfang; Tian, Zhigang; Yokoyama, Wayne M
2014-01-01
Natural killer (NK) cells belong to the innate immune system; they can control virus infections and developing tumors by cytotoxicity and producing inflammatory cytokines. Most studies of mouse NK cells, however, have focused on conventional NK (cNK) cells in the spleen. Recently, we described two populations of liver NK cells, tissue-resident NK (trNK) cells and those resembling splenic cNK cells. However, their lineage relationship was unclear; trNK cells could be developing cNK cells, related to thymic NK cells, or a lineage distinct from both cNK and thymic NK cells. Herein we used detailed transcriptomic, flow cytometric, and functional analysis and transcription factor-deficient mice to determine that liver trNK cells form a distinct lineage from cNK and thymic NK cells. Taken together with analysis of trNK cells in other tissues, there are at least four distinct lineages of NK cells: cNK, thymic, liver (and skin) trNK, and uterine trNK cells. DOI: http://dx.doi.org/10.7554/eLife.01659.001 PMID:24714492
Tang, Qin; Iyer, Sowmya; Lobbardi, Riadh; Moore, John C; Chen, Huidong; Lareau, Caleb; Hebert, Christine; Shaw, McKenzie L; Neftel, Cyril; Suva, Mario L; Ceol, Craig J; Bernards, Andre; Aryee, Martin; Pinello, Luca; Drummond, Iain A; Langenau, David M
2017-10-02
Recent advances in single-cell, transcriptomic profiling have provided unprecedented access to investigate cell heterogeneity during tissue and organ development. In this study, we used massively parallel, single-cell RNA sequencing to define cell heterogeneity within the zebrafish kidney marrow, constructing a comprehensive molecular atlas of definitive hematopoiesis and functionally distinct renal cells found in adult zebrafish. Because our method analyzed blood and kidney cells in an unbiased manner, our approach was useful in characterizing immune-cell deficiencies within DNA-protein kinase catalytic subunit ( prkdc ), interleukin-2 receptor γ a ( il2rga ), and double-homozygous-mutant fish, identifying blood cell losses in T, B, and natural killer cells within specific genetic mutants. Our analysis also uncovered novel cell types, including two classes of natural killer immune cells, classically defined and erythroid-primed hematopoietic stem and progenitor cells, mucin-secreting kidney cells, and kidney stem/progenitor cells. In total, our work provides the first, comprehensive, single-cell, transcriptomic analysis of kidney and marrow cells in the adult zebrafish. © 2017 Tang et al.
Iyer, Sowmya; Lobbardi, Riadh; Chen, Huidong; Hebert, Christine; Shaw, McKenzie L.; Neftel, Cyril; Suva, Mario L.; Bernards, Andre; Aryee, Martin; Drummond, Iain A.
2017-01-01
Recent advances in single-cell, transcriptomic profiling have provided unprecedented access to investigate cell heterogeneity during tissue and organ development. In this study, we used massively parallel, single-cell RNA sequencing to define cell heterogeneity within the zebrafish kidney marrow, constructing a comprehensive molecular atlas of definitive hematopoiesis and functionally distinct renal cells found in adult zebrafish. Because our method analyzed blood and kidney cells in an unbiased manner, our approach was useful in characterizing immune-cell deficiencies within DNA–protein kinase catalytic subunit (prkdc), interleukin-2 receptor γ a (il2rga), and double-homozygous–mutant fish, identifying blood cell losses in T, B, and natural killer cells within specific genetic mutants. Our analysis also uncovered novel cell types, including two classes of natural killer immune cells, classically defined and erythroid-primed hematopoietic stem and progenitor cells, mucin-secreting kidney cells, and kidney stem/progenitor cells. In total, our work provides the first, comprehensive, single-cell, transcriptomic analysis of kidney and marrow cells in the adult zebrafish. PMID:28878000
Inflammatory bowel disease: cause and immunobiology.
Baumgart, Daniel C; Carding, Simon R
2007-05-12
Crohn's disease and ulcerative colitis are idiopathic inflammatory bowel disorders. In this paper, we discuss how environmental factors (eg, geography, cigarette smoking, sanitation and hygiene), infectious microbes, ethnic origin, genetic susceptibility, and a dysregulated immune system can result in mucosal inflammation. After describing the symbiotic interaction of the commensal microbiota with the host, oral tolerance, epithelial barrier function, antigen recognition, and immunoregulation by the innate and adaptive immune system, we examine the initiating and perpetuating events of mucosal inflammation. We pay special attention to pattern-recognition receptors, such as toll-like receptors and nucleotide-binding-oligomerisation-domains (NOD), NOD-like receptors and their mutual interaction on epithelial cells and antigen-presenting cells. We also discuss the important role of dendritic cells in directing tolerance and immunity by modulation of subpopulations of effector T cells, regulatory T cells, Th17 cells, natural killer T cells, natural killer cells, and monocyte-macrophages in mucosal inflammation. Implications for novel therapies, which are discussed in detail in the second paper in this Series, are covered briefly.
NASA Astrophysics Data System (ADS)
Taik Lim, Yong; Cho, Mi Young; Noh, Young-Woock; Chung, Jin Woong; Chung, Bong Hyun
2009-11-01
This study describes the development of near-infrared optical imaging technology for the monitoring of immunotherapeutic cell-based cancer therapy using natural killer (NK) cells labeled with fluorescent nanocrystals. Although NK cell-based immunotherapeutic strategies have drawn interest as potent preclinical or clinical methods of cancer therapy, there are few reports documenting the molecular imaging of NK cell-based cancer therapy, primarily due to the difficulty of labeling of NK cells with imaging probes. Human natural killer cells (NK92MI) were labeled with anti-human CD56 antibody-coated quantum dots (QD705) for fluorescence imaging. FACS analysis showed that the NK92MI cells labeled with anti-human CD56 antibody-coated QD705 have no effect on the cell viability. The effect of anti-human CD56 antibody-coated QD705 labeling on the NK92MI cell function was investigated by measuring interferon gamma (IFN- γ) production and cytolytic activity. Finally, the NK92MI cells labeled with anti-human CD56 antibody-coated QD705 showed a therapeutic effect similar to that of unlabeled NK92MI cells. Images of intratumorally injected NK92MI cells labeled with anti-human CD56 antibody-coated could be acquired using near-infrared optical imaging both in vivo and in vitro. This result demonstrates that the immunotherapeutic cells labeled with fluorescent nanocrystals can be a versatile platform for the effective tracking of injected therapeutic cells using optical imaging technology, which is very important in cell-based cancer therapies.
Immunosuppressive Effects of Triclosan, Nonylphenol, and DDT on Human Natural Killer Cells In Vitro
Udoji, Felicia; Martin, Tamara; Etherton, Rachel; Whalen, Margaret M.
2010-01-01
Human natural killer (NK) cells are a first line immune defense against tumor cells and virally infected cells. If their function is impaired, it leaves an individual more susceptible to cancer development or viral infection. The ability of compounds that contaminate the environment to suppress the function of NK cells could contribute to increased risk of cancer development. There are a wide spectrum of compounds that significantly contaminate water and food that is consumed by humans leading to accumulation of some of these compounds in human tissues. In the current study, we examined the ability of three such compounds to diminish the function of human NK cells. Triclosan (TC) is an antimicrobial agent used in a large number of antibacterial soaps. Nonylphenol (NP) is a degradation product of compounds used as surfactants and as stabilizers in plastics. 4, 4′-dichlorodiphenyltrichloroethane (DDT) is a pesticide that is mainly used to control mosquitoes. The compounds were examined for their ability to suppress NK function following exposures of 1 hr, 24 hr, 48 hr, and 6 d. Each agent was able to substantially decrease NK lytic function within 24 hr. At a concentration of 5 μM, both TC and NP inhibited NK lytic function by 87 and 30%, respectively; DDT decreased function by 55% at 2.5 μM. The negative effects of each of these compounds persisted and/or intensified following a brief (1 hr) exposure to the compounds, indicating that the impairment of function cannot be eliminated by removal of the compound under in vitro conditions. PMID:20297919
The Functions of Type I and Type II Natural Killer T (NKT) Cells in Inflammatory Bowel Diseases
Liao, Chia-Min; Zimmer, Michael I.; Wang, Chyung-Ru
2013-01-01
CD1d-restricted natural killer T (NKT) cells are a distinct subset of T cells that rapidly produce an array of cytokines upon activation and play a critical role in regulating various immune responses. NKT cells are classified into two groups based on differences in T cell receptor (TCR) usage. Type I NKT cells have an invariant TCRα-chain and are readily detectable by α-galactosylceramide (α-GalCer)-loaded CD1d tetramers. Type II NKT cells have a more diverse TCR repertoire and cannot be directly identified. Both types of NKT cells as well as multiple CD1d-expressing cell types are present in the intestine and their interactions are likely to be modulated by pathogenic and commensal microbes, which in turn contribute to the intestinal immune responses in health and disease. Indeed, in several animal models of inflammatory bowel disease (IBD), Type I NKT cells have been shown to make both protective and pathogenic contributions to disease. In contrast, in human patients suffering from ulcerative colitis (UC), and a mouse model in which both CD1d expression and the frequency of Type II NKT cells are increased, Type II NKT cells appear to promote intestinal inflammation. In this review, we summarize present knowledge on the antigen recognition, activation and function of NKT cells with a particular focus on their role in IBD, and discuss factors that may influence the functional outcome of NKT cell responses in intestinal inflammation. PMID:23518808
Massage Therapy Research Review
Field, Tiffany
2017-01-01
Moderate pressure massage has contributed to many positive effects including increased weight gain in preterm infants, reduced pain in different syndromes including fibromyalgia and rheumatoid arthritis, enhanced attentiveness, reduced depression and enhanced immune function (increased natural killer cells and natural killer cell activity). Surprisingly, these recent studies have not been reviewed, highlighting the need for the current review. When moderate and light pressure massage have been compared in laboratory studies, moderate pressure massage reduced depression, anxiety and heart rate, and it altered EEG patterns, as in a relaxation response. Moderate pressure massage has also led to increased vagal activity and decreased cortisol levels. Functional magnetic resonance imaging data have suggested that moderate pressure massage was represented in several brain regions including the amygdala, the hypothalamus and the anterior cingulate cortex, all areas involved in stress and emotion regulation. Further research is needed to identify underlying neurophysiological and biochemical mechanisms associated with moderate pressure massage. PMID:25172313
Massage therapy research review.
Field, Tiffany
2014-11-01
Moderate pressure massage has contributed to many positive effects including increased weight gain in preterm infants, reduced pain in different syndromes including fibromyalgia and rheumatoid arthritis, enhanced attentiveness, reduced depression and enhanced immune function (increased natural killer cells and natural killer cell activity).Surprisingly, these recent studies have not been reviewed, highlighting the need for the current review. When moderate and light pressure massage have been compared in laboratory studies, moderate pressure massage reduced depression, anxiety and heart rate, and it altered EEG patterns, as in a relaxation response. Moderate pressure massage has also led to increased vagal activity and decreased cortisol levels. Functional magnetic resonance imaging data have suggested that moderate pressure massage was represented in several brain regions including the amygdala, the hypothalamus and the anterior cingulate cortex, all areas involved in stress and emotion regulation. Further research is needed to identify underlying neurophysiological and biochemical mechanisms associated with moderate pressure massage. Copyright © 2014 Elsevier Ltd. All rights reserved.
2012-04-11
neutralization) and non-neutralizing antibody-dependent HIV inhibition, which may provide the opportunity to delineate the dominant antibody function (s) in...immunity, there has been a considerable effort to develop a vaccine that will elicit antibodies with some or all of these functions [19], and to... function (s) in polyclonal vaccine responses. 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT Same as Report (SAR) 18
Hazeldine, Jon; Lord, Janet M
2013-09-01
Forming the first line of defence against virally infected and malignant cells, natural killer (NK) cells are critical effector cells of the innate immune system. With age, significant impairments have been reported in the two main mechanisms by which NK cells confer host protection: direct cytotoxicity and the secretion of immunoregulatory cytokines and chemokines. In elderly subjects, decreased NK cell activity has been shown to be associated with an increased incidence and severity of viral infection, highlighting the clinical implications that age-associated changes in NK cell biology have on the health of older adults. However, is an increased susceptibility to viral infection the only consequence of these age-related changes in NK cell function? Recently, evidence has emerged that has shown that in addition to eliminating transformed cells, NK cells are involved in many other biological processes such as immune regulation, anti-microbial immune responses and the recognition and elimination of senescent cells, novel functions that involve NK-mediated cytotoxicity and/or cytokine production. Thus, the decrease in NK cell function that accompanies physiological ageing is likely to have wider implications for the health of older adults than originally thought. Here, we give a detailed description of the changes in NK cell biology that accompany human ageing and propose that certain features of the ageing process such as: (i) the increased reactivation rates of latent Mycobacterium tuberculosis, (ii) the slower resolution of inflammatory responses and (iii) the increased incidence of bacterial and fungal infection are attributable in part to an age-associated decline in NK cell function. Copyright © 2013 Elsevier B.V. All rights reserved.
Funke, Christina; King, Donald P; McBain, Jim F; Adelung, Dieter; Stott, Jeffrey L
2003-05-30
Interleukin-6 (IL-6) is a cytokine that can reach detectable systemic levels and is a major inducer of the acute phase response. As such, clinical assays to identify this cytokine in mammalian sera are of diagnostic value. A 558 base-pair (bp) fragment of killer whale IL-6 was cloned and expressed as a 21 kDa protein in Escherichia coli. Biological activity of the recombinant killer whale IL-6 (rkwIL-6) was demonstrated using the IL-6-dependent B9 mouse hybridoma cell line; acute phase sera from a killer whale and supernatants from lipopolysaccharide (LPS)-stimulated killer whale peripheral blood mononuclear cells (PBMCs) also supported the proliferation of the B9 hybridoma. Rat anti-mouse IL-6 receptor antibody effectively blocked biological activity of all three sources of IL-6. Polyclonal antisera, specific for the recombinant protein, were obtained by successive immunization of a rabbit with rkwIL-6. The polyclonal antibody was capable of neutralizing the biological activity of both recombinant and native kwIL-6. A competitive enzyme-linked immunosorbent assay (ELISA) was developed using the polyclonal rabbit anti-rkwIL-6 and the recombinant protein; sensitivity of the assay was in the range of 1 ng/ml. The ELISA was subsequently used to identify the presence of native IL-6 in acute phase sera of two species of delphinidae, a killer whale and a bottlenose dolphin. The application of quantitative cytokine assays as diagnostic tools for monitoring cetacean health are becoming feasible as many animals are now being trained for fluke presentation, making blood collection a routine procedure.
Nieman, David C; Bishop, Nicolette C
2006-07-01
Although epidemiological data indicate that athletes are at increased risk of upper respiratory tract infection during periods of heavy training and the 1 - 2 week period following endurance race events, there is very limited information on the responses to football training and match-play. For several hours after heavy exertion, components of both the innate (e.g. natural killer cell activity and neutrophil oxidative burst activity) and adaptive (e.g. T and B cell function) immune system exhibit suppressed function. Although such responses to football training and competition do not appear to be as pronounced, variations in immune cell numbers and function are reported in professional footballers over the course of a season. Attempts have been made through nutritional means (e.g. glutamine, vitamins C and E, and carbohydrate supplementation) to attenuate immune changes following intensive exercise and thus lower the risk of upper respiratory tract infection. Carbohydrate supplementation during heavy exercise has emerged as a partial countermeasure and attenuates increases in blood neutrophil counts, stress hormones, and inflammatory cytokines, but has little effect on decrements in salivary IgA output or natural killer cell function. Animal research indicates that other nutritional components such as beta-glucan, quercetin, and curcumin warrant human investigations to determine if they are effective countermeasures to exercise-induced immune dysfunction.
Dinges, D F; Douglas, S D; Zaugg, L; Campbell, D E; McMann, J M; Whitehouse, W G; Orne, E C; Kapoor, S C; Icaza, E; Orne, M T
1994-05-01
The hypothesis that sleep deprivation depresses immune function was tested in 20 adults, selected on the basis of their normal blood chemistry, monitored in a laboratory for 7 d, and kept awake for 64 h. At 2200 h each day measurements were taken of total leukocytes (WBC), monocytes, granulocytes, lymphocytes, eosinophils, erythrocytes (RBC), B and T lymphocyte subsets, activated T cells, and natural killer (NK) subpopulations (CD56/CD8 dual-positive cells, CD16-positive cells, CD57-positive cells). Functional tests included NK cytotoxicity, lymphocyte stimulation with mitogens, and DNA analysis of cell cycle. Sleep loss was associated with leukocytosis and increased NK cell activity. At the maximum sleep deprivation, increases were observed in counts of WBC, granulocytes, monocytes, NK activity, and the proportion of lymphocytes in the S phase of the cell cycle. Changes in monocyte counts correlated with changes in other immune parameters. Counts of CD4, CD16, CD56, and CD57 lymphocytes declined after one night without sleep, whereas CD56 and CD57 counts increased after two nights. No changes were observed in other lymphocyte counts, in proliferative responses to mitogens, or in plasma levels of cortisol or adrenocorticotropin hormone. The physiologic leukocytosis and NK activity increases during deprivation were eliminated by recovery sleep in a manner parallel to neurobehavioral function, suggesting that the immune alterations may be associated with biological pressure for sleep.
Dinges, D F; Douglas, S D; Zaugg, L; Campbell, D E; McMann, J M; Whitehouse, W G; Orne, E C; Kapoor, S C; Icaza, E; Orne, M T
1994-01-01
The hypothesis that sleep deprivation depresses immune function was tested in 20 adults, selected on the basis of their normal blood chemistry, monitored in a laboratory for 7 d, and kept awake for 64 h. At 2200 h each day measurements were taken of total leukocytes (WBC), monocytes, granulocytes, lymphocytes, eosinophils, erythrocytes (RBC), B and T lymphocyte subsets, activated T cells, and natural killer (NK) subpopulations (CD56/CD8 dual-positive cells, CD16-positive cells, CD57-positive cells). Functional tests included NK cytotoxicity, lymphocyte stimulation with mitogens, and DNA analysis of cell cycle. Sleep loss was associated with leukocytosis and increased NK cell activity. At the maximum sleep deprivation, increases were observed in counts of WBC, granulocytes, monocytes, NK activity, and the proportion of lymphocytes in the S phase of the cell cycle. Changes in monocyte counts correlated with changes in other immune parameters. Counts of CD4, CD16, CD56, and CD57 lymphocytes declined after one night without sleep, whereas CD56 and CD57 counts increased after two nights. No changes were observed in other lymphocyte counts, in proliferative responses to mitogens, or in plasma levels of cortisol or adrenocorticotropin hormone. The physiologic leukocytosis and NK activity increases during deprivation were eliminated by recovery sleep in a manner parallel to neurobehavioral function, suggesting that the immune alterations may be associated with biological pressure for sleep. PMID:7910171
Peixoto, António; Evaristo, César; Munitic, Ivana; Monteiro, Marta; Charbit, Alain; Rocha, Benedita; Veiga-Fernandes, Henrique
2007-01-01
To study in vivo CD8 T cell differentiation, we quantified the coexpression of multiple genes in single cells throughout immune responses. After in vitro activation, CD8 T cells rapidly express effector molecules and cease their expression when the antigen is removed. Gene behavior after in vivo activation, in contrast, was quite heterogeneous. Different mRNAs were induced at very different time points of the response, were transcribed during different time periods, and could decline or persist independently of the antigen load. Consequently, distinct gene coexpression patterns/different cell types were generated at the various phases of the immune responses. During primary stimulation, inflammatory molecules were induced and down-regulated shortly after activation, generating early cells that only mediated inflammation. Cytotoxic T cells were generated at the peak of the primary response, when individual cells simultaneously expressed multiple killer molecules, whereas memory cells lost killer capacity because they no longer coexpressed killer genes. Surprisingly, during secondary responses gene transcription became permanent. Secondary cells recovered after antigen elimination were more efficient killers than cytotoxic T cells present at the peak of the primary response. Thus, primary responses produced two transient effector types. However, after boosting, CD8 T cells differentiate into long-lived killer cells that persist in vivo in the absence of antigen. PMID:17485515
Immune function in Amazonian horticulturalists
Blackwell, Aaron D.; Trumble, Benjamin C.; Suarez, Ivan Maldonado; Stieglitz, Jonathan; Beheim, Bret; Snodgrass, J. Josh; Kaplan, Hillard; Gurven, Michael
2016-01-01
Background Amazonian populations are exposed to diverse parasites and pathogens, including protozoal, bacterial, fungal, and helminthic infections. Yet much of our understanding of the immune system is based on industrialised populations where these infections are relatively rare. Aim We examine distributions and age-related differences in 22 measures of immune function for Bolivian forager-horticulturalists and US and European populations. Subjects and Methods Subjects were 6,338 Tsimane aged 0–90 years. Blood samples collected between 2004–2014 were analysed for 5-part blood differentials, C-reactive protein, erythrocyte sedimentation rate (ESR), and total immunoglobulins E, G, A, and M. Flow cytometry was used to quantify naive and non-naïve CD4 and CD8 T cells, natural killer cells, and B cells. Results Compared to reference populations, Tsimane have elevated levels of most immunological parameters, particularly immunoglobulins, eosinophils, ESR, B cells, and natural killer cells. However, monocytes and basophils are reduced and naïve CD4 cells depleted in older age groups. Conclusion Tsimane ecology leads to lymphocyte repertoires and immunoglobulin profiles that differ from those observed in industrialised populations. These differences have consequences for disease susceptibility and co-vary with patterns of other life history traits, such as growth and reproduction. PMID:27174705
Role of interleukin (IL)-17 and T-helper (Th)17 cells in cancer.
Song, Yang; Yang, Jian Ming
2017-11-04
Interleukin-17 (IL-17), a pleiotropic proinflammatory cytokine, is reported to be significantly generated by a distinct subset of CD4 + T-cells, upgrading cancer-elicited inflammation and preventing cancer cells from immune surveillance. T-helper (Th)17 cells produced from naive CD4 + T cells have recently been renowned and generally accepted, gaining eminence in cancer studies and playing the effective role in context of cancer. Th17 cells are the main source of IL-17-secreting cells, It was found that other cell types produced this cytokine as well, including Group 3 innate lymphoid cells (ILC3), δγT cells, invariant natural killer T (iNKT) cells, lymphoid-tissue inducer (LTi)-like cells and Natural killer (NK) cells. Th17-associated cytokines give impetus to tumor progression, or inducing angiogenesis and metastasis. This review demonstrates an understanding on how the pro- or antitumor function of Th17 cells and IL-17 may change cancer progression, leading to the appearance of complex and pivotal biologic activities in tumor. Copyright © 2017 Elsevier Inc. All rights reserved.
Capuano, Cristina; Battella, Simone; Pighi, Chiara; Franchitti, Lavinia; Turriziani, Ombretta; Morrone, Stefania; Santoni, Angela; Galandrini, Ricciarda; Palmieri, Gabriella
2018-01-01
Natural killer (NK) cells represent a pivotal player of innate anti-tumor immune responses. The impact of environmental factors in shaping the representativity of different NK cell subsets is increasingly appreciated. Human cytomegalovirus (HCMV) infection profoundly affects NK cell compartment, as documented by the presence of a CD94/NKG2C + FcεRIγ - long-lived "memory" NK cell subset, endowed with enhanced CD16-dependent functional capabilities, in a fraction of HCMV-seropositive subjects. However, the requirements for memory NK cell pool establishment/maintenance and activation have not been fully characterized yet. Here, we describe the capability of anti-CD20 tumor-targeting therapeutic monoclonal antibodies (mAbs) to drive the selective in vitro expansion of memory NK cells and we show the impact of donor' HCMV serostatus and CD16 affinity ligation conditions on this event. In vitro expanded memory NK cells maintain the phenotypic and functional signature of their freshly isolated counterpart; furthermore, our data demonstrate that CD16 affinity ligation conditions differently affect memory NK cell proliferation and functional activation, as rituximab-mediated low-affinity ligation represents a superior proliferative stimulus, while high-affinity aggregation mediated by glycoengineered obinutuzumab results in improved multifunctional responses. Our work also expands the molecular and functional characterization of memory NK cells, and investigates the possible impact of CD16 functional allelic variants on their in vivo and in vitro expansions. These results reveal new insights in Ab-driven memory NK cell responses in a therapeutic setting and may ultimately inspire new NK cell-based intervention strategies against cancer, in which the enhanced responsiveness to mAb-bound target could significantly impact therapeutic efficacy.
Chang, Shang-Lin; Leu, Jun-Yi; Chang, Tien-Hsien
2015-08-01
Microbes have evolved ways of interference competition to gain advantage over their ecological competitors. The use of secreted killer toxins by yeast cells through acquiring double-stranded RNA viruses is one such prominent example. Although the killer behaviour has been well studied in laboratory yeast strains, our knowledge regarding how killer viruses are spread and maintained in nature and how yeast cells co-evolve with viruses remains limited. We investigated these issues using a panel of 81 yeast populations belonging to three Saccharomyces sensu stricto species isolated from diverse ecological niches and geographic locations. We found that killer strains are rare among all three species. In contrast, killer toxin resistance is widespread in Saccharomyces paradoxus populations, but not in Saccharomyces cerevisiae or Saccharomyces eubayanus populations. Genetic analyses revealed that toxin resistance in S. paradoxus is often caused by dominant alleles that have independently evolved in different populations. Molecular typing identified one M28 and two types of M1 killer viruses in those killer strains. We further showed that killer viruses of the same type could lead to distinct killer phenotypes under different host backgrounds, suggesting co-evolution between the viruses and hosts in different populations. Taken together, our data suggest that killer viruses vary in their evolutionary histories even within closely related yeast species. © 2015 John Wiley & Sons Ltd.
Modeling Human Natural Killer Cell Development in the Era of Innate Lymphoid Cells
Scoville, Steven D.; Freud, Aharon G.; Caligiuri, Michael A.
2017-01-01
Decades after the discovery of natural killer (NK) cells, their developmental pathways in mice and humans have not yet been completely deciphered. Accumulating evidence indicates that NK cells can develop in multiple tissues throughout the body. Moreover, detailed and comprehensive models of NK cell development were proposed soon after the turn of the century. However, with the recent identification and characterization of other subtypes of innate lymphoid cells (ILCs), which show some overlapping functional and phenotypic features with NK cell developmental intermediates, the distinct stages through which human NK cells develop from early hematopoietic progenitor cells remain unclear. Thus, there is a need to reassess and refine older models of NK cell development in the context of new data and in the era of ILCs. Our group has focused on elucidating the developmental pathway of human NK cells in secondary lymphoid tissues (SLTs), including tonsils and lymph nodes. Here, we provide an update of recent progress that has been made with regard to human NK cell development in SLTs, and we discuss these new findings in the context of contemporary models of ILC development. PMID:28396671
Kobayashi, Eiji; Motoi, Sotaro; Sugiura, Masahito; Kajikawa, Masunori; Kojima, Shuji; Kohroki, Junya; Masuho, Yasuhiko
2014-09-01
Antibody-dependent cellular cytotoxicity (ADCC) mediated by natural killer (NK) cells is a major mechanism of tumor therapy with antibodies. NK cells not only manifest cytotoxicity but also secrete a variety of cytokines/chemokines that regulate immune responses. Using a retroviral vector, in this study we established a KHYG-1 cell line that stably expresses FcγRIIIA (CD16A). The KHYG-1/FcγRIIIA cells exerted potent antibody concentration-dependent ADCC, whereas parental KHYG-1 cells did not. In contrast, without antibody, the natural killer activity of KHYG-1/FcγRIIIA cells was less potent than that of parental KHYG-1 cells. During the course of ADCC, KHYG-1/FcγRIIIA cells secreted IFN-γ and MIP-1α dependent upon antibody concentration, but parental KHYG-1 cells did not. These results suggest that KHYG-1/FcγRIIIA cells would be useful in studies to elucidate the function of NK cells and the mechanism of ADCC. Copyright © 2014 Elsevier B.V. All rights reserved.
Modeling Human Natural Killer Cell Development in the Era of Innate Lymphoid Cells.
Scoville, Steven D; Freud, Aharon G; Caligiuri, Michael A
2017-01-01
Decades after the discovery of natural killer (NK) cells, their developmental pathways in mice and humans have not yet been completely deciphered. Accumulating evidence indicates that NK cells can develop in multiple tissues throughout the body. Moreover, detailed and comprehensive models of NK cell development were proposed soon after the turn of the century. However, with the recent identification and characterization of other subtypes of innate lymphoid cells (ILCs), which show some overlapping functional and phenotypic features with NK cell developmental intermediates, the distinct stages through which human NK cells develop from early hematopoietic progenitor cells remain unclear. Thus, there is a need to reassess and refine older models of NK cell development in the context of new data and in the era of ILCs. Our group has focused on elucidating the developmental pathway of human NK cells in secondary lymphoid tissues (SLTs), including tonsils and lymph nodes. Here, we provide an update of recent progress that has been made with regard to human NK cell development in SLTs, and we discuss these new findings in the context of contemporary models of ILC development.
A STED-FLIM microscope applied to imaging the natural killer cell immune synapse
NASA Astrophysics Data System (ADS)
Lenz, M. O.; Brown, A. C. N.; Auksorius, E.; Davis, D. M.; Dunsby, C.; Neil, M. A. A.; French, P. M. W.
2011-03-01
We present a stimulated emission depletion (STED) fluorescence lifetime imaging (FLIM) microscope, excited by a microstructured optical fibre supercontinuum source that is pumped by a femtosecond Ti:Sapphire-laser, which is also used for depletion. Implemented using a piezo-scanning stage on a laser scanning confocal fluorescence microscope system with FLIM realised using time correlated single photon counting (TCSPC), this provides convenient switching between confocal and STED-FLIM with spatial resolution down to below 60 nm. We will present our design considerations to make a robust instrument for biological applications including a comparison between fixed phase plate and spatial light modulator (SLM) approaches to shape the STED beam and the correlation of STED and confocal FLIM microscopy. Following our previous application of FLIM-FRET to study intercellular signalling at the immunological synapse (IS), we are employing STED microscopy to characterize the spatial distribution of cellular molecules with subdiffraction resolution at the IS. In particular, we are imaging cytoskeletal structure at the Natural Killer cell activated immune synapse. We will also present our progress towards multilabel STED microscopy to determine how relative spatial molecular organization, previously undetectable by conventional microscopy techniques, is important for NK cell cytotoxic function. Keywords: STED, Stimulated Emission Depletion Microscopy, Natural Killer (NK) cell, Fluorescence lifetime imaging, FLIM, Super resolution microscopy.
Saroha, Ashish; Pewzner-Jung, Yael; Ferreira, Natalia S; Sharma, Piyush; Jouan, Youenn; Kelly, Samuel L; Feldmesser, Ester; Merrill, Alfred H; Trottein, François; Paget, Christophe; Lang, Karl S; Futerman, Anthony H
2017-01-01
The role of sphingolipids (SLs) in the immune system has come under increasing scrutiny recently due to the emerging contributions that these important membrane components play in regulating a variety of immunological processes. The acyl chain length of SLs appears particularly critical in determining SL function. Here, we show a role for very-long acyl chain SLs (VLC-SLs) in invariant natural killer T ( i NKT) cell maturation in the thymus and homeostasis in the liver. Ceramide synthase 2-null mice, which lack VLC-SLs, were susceptible to a hepatotropic strain of lymphocytic choriomeningitis virus, which is due to a reduction in the number of i NKT cells. Bone marrow chimera experiments indicated that hematopoietic-derived VLC-SLs are essential for maturation of i NKT cells in the thymus, whereas parenchymal-derived VLC-SLs are crucial for i NKT cell survival and maintenance in the liver. Our findings suggest a critical role for VLC-SL in i NKT cell physiology.
The Yin and Yang of Innate Lymphoid Cells in Cancer.
Carrega, Paolo; Campana, Stefania; Bonaccorsi, Irene; Ferlazzo, Guido
2016-11-01
The recent appreciation of novel subsets of innate lymphoid cells (ILCs) as important regulators of tissue homeostasis, inflammation and repair, raise questions regarding the presence and role of these cells in cancer tissues. In addition to natural killer and fetal lymphoid tissue inducer (LTi) cells, the ILC family comprises non-cytolytic, cytokine-producing cells that are classified into ILC1, ILC2 and ILC3 based on phenotypic and functional characteristics. Differently from natural killer cells, which are the prototypical members of ILC1 and whose role in tumors is better established, the involvement of other ILC subsets in cancer progression or resistance is still fuzzy and in several instances controversial, since current studies indicate both context-dependent beneficial or pathogenic effects. Here, we review the current knowledge regarding the involvement of these novel ILC subsets in the context of tumor immunology, highlighting how ILC subsets might behave either as friends or foes. Copyright © 2016 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.
Coombes, Janine L; Han, Seong-Ji; van Rooijen, Nico; Raulet, David H; Robey, Ellen A
2012-07-26
Infection leads to heightened activation of natural killer (NK) cells, a process that likely involves direct cell-to-cell contact, but how this occurs in vivo is poorly understood. We have used two-photon laser-scanning microscopy in conjunction with Toxoplasma gondii mouse infection models to address this question. We found that after infection, NK cells accumulated in the subcapsular region of the lymph node, where they formed low-motility contacts with collagen fibers and CD169(+) macrophages. We provide evidence that interactions with collagen regulate NK cell migration, whereas CD169(+) macrophages increase the activation state of NK cells. Interestingly, a subset of CD169(+) macrophages that coexpress the inflammatory monocyte marker Ly6C had the most potent ability to activate NK cells. Our data reveal pathways through which NK cell migration and function are regulated after infection and identify an important accessory cell population for activation of NK cell responses in lymph nodes. Copyright © 2012 The Authors. Published by Elsevier Inc. All rights reserved.
IL-15/IL-15 receptor biology: a guided tour through an expanding universe.
Budagian, Vadim; Bulanova, Elena; Paus, Ralf; Bulfone-Paus, Silvia
2006-08-01
The cytokine interleukin-15 (IL-15) has a key role in promoting survival, proliferation and activation of natural killer (NK) and CD8+ T cells. Despite its functional similarities to IL-2, IL-15 affects a wider range of target cell populations and utilizes different mechanisms of signaling. Here, we review recent advances in the IL-15-mediated signaling, and in the functional properties on cells besides T lymphocytes and NK cells. These are discussed in the context of their potential clinical and therapeutic relevance.
Kaisho, Tsuneyasu; Tsutsui, Hiroko; Tanaka, Takashi; Tsujimura, Tohru; Takeda, Kiyoshi; Kawai, Taro; Yoshida, Nobuaki; Nakanishi, Kenji; Akira, Shizuo
1999-01-01
We have investigated in vivo roles of CCAAT/enhancer binding protein γ (C/EBPγ) by gene targeting. C/EBPγ-deficient (C/EBPγ2/−) mice showed a high mortality rate within 48 h after birth. To analyze the roles of C/EBPγ in lymphoid lineage cells, bone marrow chimeras were established. C/EBPγ2/− chimeras showed normal T and B cell development. However, cytolytic functions of their splenic natural killer (NK) cells after stimulation with cytokines such as interleukin (IL)-12, IL-18, and IL-2 were significantly reduced as compared with those of control chimera NK cells. In addition, the ability of C/EBPγ−/− chimera splenocytes to produce interferon (IFN)-γ in response to IL-12 and/or IL-18 was markedly impaired. NK cells could be generated in vitro with normal surface marker expression in the presence of IL-15 from C/EBPγ2/− newborn spleen cells. However, they also showed lower cytotoxic activity and IFN-γ production when stimulated with IL-12 plus IL-18 than control NK cells, as observed in C/EBPγ2/− chimera splenocytes. In conclusion, our study reveals that C/EBPγ is a critical transcription factor involved in the functional maturation of NK cells. PMID:10587348
Enhancing Natural Killer Cell Mediated Targeting and Responses to Myeloid Leukemias
2017-10-01
Syndromes , AML – Acute Myeloid Leukemia, BiKE – Bi-specific Killer Engager, TriKE – Tri-specific Killer E 16. SECURITY CLASSIFICATION OF: 17...Natural Killer CML – Chronic Myeloid Leukemia MDS – Myelodysplastic Syndromes AML – Acute Myeloid Leukemia BiKE – Bi-specific Killer Engager TriKE...incidence of myeloid malignancies is increased due to exposure to ionizing radiation , chemicals, and other agents during deployment. Although
Pregnancy immunology: decidual immune cells.
Sanguansermsri, Donruedee; Pongcharoen, Sutatip
2008-01-01
Human pregnancy is a complex process. Placental development depends on the function of secretory molecules produced by placental trophoblast cells as well as by maternal uterine immune cells within the decidua. These decidual immune cells are T cells, natural killer cells, macrophages and dendritic cells. The interactions between the trophoblast cells and the maternal immune cells have an impact on the outcome of the pregnancy. Knowledge about the phenotypes and functions of the maternal immune cells in normal and pathological pregnancies including recurrent spontaneous abortions, preeclampsia and hydatidiform moles may improve our understanding of the immunobiology of the normal pregnancy as a whole and may provide approaches for improving the treatment of pathological pregnancies.
Nattermann, Jacob; Nischalke, Hans Dieter; Hofmeister, Valeska; Ahlenstiel, Golo; Zimmermann, Henning; Leifeld, Ludger; Weiss, Elisabeth H.; Sauerbruch, Tilman; Spengler, Ulrich
2005-01-01
Impaired activity of natural killer cells has been proposed as a mechanism contributing to viral persistence in hepatitis C virus (HCV) infection. Natural cytotoxicity is regulated by interactions of HLA-E with inhibitory CD94/NKG2A receptors on natural killer (NK) cells. Here, we studied whether HCV core encodes peptides that bind to HLA-E and inhibit natural cytotoxicity. We analyzed 30 HCV core-derived peptides. Peptide-induced stabilization of HLA-E expression was measured flow cytometrically after incubating HLA-E-transfected cells with peptides. NK cell function was studied with a 51chromium-release-assay. Intrahepatic HLA-E expression was analyzed by an indirect immunoperoxidase technique and flow cytometry of isolated cells using a HLA-E-specific antibody. We identified peptide aa35–44, a well-characterized HLA-A2 restricted T cell epitope, as a peptide stabilizing HLA-E expression and thereby inhibiting NK cell-mediated lysis. Blocking experiments confirmed that this inhibitory effect of peptide aa35–44 on natural cytotoxicity was mediated via interactions between CD94/NKG2A receptors and enhanced HLA-E expression. In line with these in vitro data we found enhanced intrahepatic HLA-E expression on antigen-presenting cells in HCV-infected patients. Our data indicate the existence of T cell epitopes that can be recognized by HLA-A2 and HLA-E. This dual recognition may contribute to viral persistence in hepatitis C. PMID:15681828
Ravell, Juan; Chaigne-Delalande, Benjamin; Lenardo, Michael
2014-12-01
To describe the role of the magnesium transporter 1 (MAGT1) in the pathogenesis of 'X-linked immunodeficiency with magnesium defect, Epstein-Barr virus (EBV) infection, and neoplasia' (XMEN) disease and its clinical implications. The magnesium transporter protein MAGT1 participates in the intracellular magnesium ion (Mg) homeostasis and facilitates a transient Mg influx induced by the activation of the T-cell receptor. Loss-of-function mutations in MAGT1 cause an immunodeficiency named 'XMEN syndrome', characterized by CD4 lymphopenia, chronic EBV infection, and EBV-related lymphoproliferative disorders. Patients with XMEN disease have impaired T-cell activation and decreased cytolytic function of natural killer (NK) and CD8 T cells because of decreased expression of the NK stimulatory receptor 'natural-killer group 2, member D' (NKG2D). Patients may have defective specific antibody responses secondary to T cell dysfunction, but B cells have not been shown to be directly affected by mutations in MAGT1. XMEN disease has revealed a novel role for free intracellular magnesium in the immune system. Further understanding of the MAGT1 signaling pathway may lead to new diagnostic and therapeutic approaches.
Agonist antibody that induces human malignant cells to kill one another
Yea, Kyungmoo; Zhang, Hongkai; Xie, Jia; Jones, Teresa M.; Lin, Chih-Wei; Francesconi, Walter; Berton, Fulvia; Fallahi, Mohammad; Sauer, Karsten; Lerner, Richard A.
2015-01-01
An attractive, but as yet generally unrealized, approach to cancer therapy concerns discovering agents that change the state of differentiation of the cancer cells. Recently, we discovered a phenomenon that we call “receptor pleiotropism” in which agonist antibodies against known receptors induce cell fates that are very different from those induced by the natural agonist to the same receptor. Here, we show that one can take advantage of this phenomenon to convert acute myeloblastic leukemic cells into natural killer cells. Upon induction with the antibody, these leukemic cells enter into a differentiation cascade in which as many as 80% of the starting leukemic cells can be differentiated. The antibody-induced killer cells make large amounts of perforin, IFN-γ, and granzyme B and attack and kill other members of the leukemic cell population. Importantly, induction of killer cells is confined to transformed cells, in that normal bone marrow cells are not induced to form killer cells. Thus, it seems possible to use agonist antibodies to change the differentiation state of cancer cells into those that attack and kill other members of the malignant clone from which they originate. PMID:26487683
Peruzzi, Giovanna; Masilamani, Madhan; Borrego, Francisco; Coligan, John E
2009-01-01
Natural killer (NK) cells are lymphocytes generally recognized as sentinels of the innate immune system due to their inherent capacity to deal with diseased (stressed) cells, including malignant and infected. This ability to recognize many potentially pathogenic situations is due to the expression of a diverse panel of activation receptors. Because NK cell activation triggers an aggressive inflammatory response, it is important to have a means of throttling this response. Hence, NK cells also express a panel of inhibitory receptors that recognize ligands expressed by "normal" cells. Little or nothing is known about the endocytosis and trafficking of NK cell receptors, which are of great relevance to understanding how NK cells maintain the appropriate balance of activating and inhibitory receptors on their cell surface. In this review, we focus on the ITIM-containing inhibitory receptor CD94/NKG2A showing that it is endocytosed by a previously undescribed macropinocytic-like process that may be related to the maintenance of its surface expression.
Welsh, R M; O'Donnell, C L; Shultz, L D
1994-01-01
The activation, proliferation, and antiviral effects of natural killer (NK) cells were examined in a newly developed stock of mice, C57BL/6JSz mice homozygous for the severe combined immunodeficiency (scid) mutation. These mice lack functional T and B cells and express the NK 1.1 alloantigen. Such NK 1.1 expression facilitates the analysis of NK cells and their depletion in vivo with a monoclonal anti-NK 1.1 antibody. These mice, therefore, provide an excellent model to examine unambiguously the interactions between viral infections and NK cells in a system devoid of adaptive immune response mechanisms. Here we show that murine cytomegalovirus (MCMV) and lymphocytic choriomeningitis virus (LCMV) infections resulted in profound levels of NK cell activation. NK cells also proliferated greatly in response to LCMV but generally to a lesser degree in response to MCMV. Depletion of the NK cell activity in vivo caused substantial increases in MCMV synthesis and MCMV-induced pathology. These results further support the concept that NK cells are major regulators of MCMV pathogenesis.
Barreira da Silva, Rosa; Graf, Claudine
2011-01-01
Human mature dendritic cells (DCs) can efficiently stimulate natural killer (NK)–cell responses without being targeted by their cytotoxicity. To understand this important regulatory crosstalk, we characterized the development of the immunologic synapse between mature DCs and resting NK cells. Conjugates between these 2 innate leukocyte populations formed rapidly, persisted for prolonged time periods and matured with DC-derived f-actin polymerization at the synapse. Polarization of IL-12 and IL-12R to the synapse coincided with f-actin polymerization, while other activating and inhibitory molecules were enriched at the interface between DCs and NK cells earlier. Functional assays revealed that inhibition of f-actin polymerization in mature synapses led to an increase of IFN-γ secretion and cytotoxicity by NK cells. This elevated NK-cell reactivity resulted from decreased inhibitory signaling in the absence of MHC class I polarization at the interface, which was observed on inhibition of f-actin polymerization in DCs. Thus, inhibitory signaling is stabilized by f-actin at the synapse between mature DCs and resting NK cells. PMID:21917751
Shoae-Hassani, Alireza; Hamidieh, Amir Ali; Behfar, Maryam; Mohseni, Rashin; Mortazavi-Tabatabaei, Seyed A; Asgharzadeh, Shahab
2017-09-01
Immune cell-derived exosomes can increase immunity against tumors. In contrast, tumor-derived exosomes can reduce the immunity and can change the tumor microenvironment to further develop and provide metastasis. These effects take place by an alteration in the innate and adaptive immune cell functions. In this experiment, we studied the natural killer (NK) cells' effectiveness on tumor cells after expansion and thereafter incubated it with exosomes. The exosomes were derived from 2 populations of NK cells: (1) naive NK cells and, (2) NK cells previously exposed to neuroblastoma (NB) cells. Moreover, we have studied the NB-derived exosomes on NK cell function. The molecular load of the characterized exosomes (by means of nanoparticle-tracking analysis, flow cytometry, scanning electron microscopy, and western blot) from NK cells exposed to the NB cell revealed their expression of natural killer cell receptors in addition to CD56, NKG2D, and KIR2DL2 receptors. These exosomes were used to treat NK cells and thereafter administered to NB tumor cells both in vitro and in vivo. Our results showed some kind of NK cells' education by the exosomes. This education from NK cells previously exposed to NB cell-derived exosomes caused efficient and greater cytotoxicity against NB tumors, but NB-derived exosomes act as tumor promoters by providing a tumor supporting niche. Hence, this method of preparing the exosomes has a dramatic effect on activation of anti-NK cells against NB cells.
Manickam, Cordelia; Nwanze, Chiadika; Ram, Daniel R; Shah, Spandan V; Smith, Scott; Jones, Rhianna; Hueber, Brady; Kroll, Kyle; Varner, Valerie; Goepfert, Paul; Jost, Stephanie; Reeves, R Keith
2018-05-03
Recently, a seemingly novel innate immune cell subset bearing features of natural killer and B cells was identified in mice. So-called NKB cells appear as first responders to infections, but whether this cell population is truly novel or is in fact a subpopulation of B cells and exists in higher primates remains unclear. The objective of this study was to identify NKB cells in primates and study the impact of HIV/SIV infections. NKB cells were quantified in both naïve and lentivirus infected rhesus macaques and humans by excluding lineage markers (CD3, CD127), and positive Boolean gating for CD20, NKG2A/C and/or NKp46. Additional phenotypic measures were conducted by RNA-probe and traditional flow cytometry. Circulating cytotoxic NKB cells were found at similar frequencies in humans and rhesus macaques (range, 0.01-0.2% of total lymphocytes). NKB cells were notably enriched in spleen (median, 0.4% of lymphocytes), but were otherwise systemically distributed in tonsil, lymph nodes, colon, and jejunum. Expression of immunoglobulins was highly variable, but heavily favoured IgM and IgA rather than IgG. Interestingly, NKB cell frequencies expanded in PBMC and colon during SIV infection, as did IgG expression, but were generally unaltered in HIV-infected humans. These results suggest a cell type expressing both natural killer and B-cell features exists in rhesus macaques and humans and are perturbed by HIV/SIV infection. The full functional niche remains unknown, but the unique phenotype and systemic distribution could make NKB cells unique targets for immunotherapeutics or vaccine strategies.
Boyadjieva, Nadka I.; Ortigüela, María; Arjona, Alvaro; Cheng, Xiaodong; Sarkar, Dipak K.
2010-01-01
Background Natural killer (NK) cell dysfunction is associated with hyperresponse of corticotropin releasing hormone (CRH) to immune challenge and with a loss of β-endorphin (BEP) neurons in fetal alcohol exposed animals. Recently, we established a method to differentiate neural stem cells into BEP neurons using cyclic adenosine monophosphate (cAMP)-elevating agents in cultures. Hence, we determined whether in vitro differentiated BEP neurons could be used for reversing the compromised stress response and immune function in fetal alcohol exposed rats. Methods To determine the effect of BEP neuron transplants on NK cell function, we implanted in vitro differentiated BEP neurons into the paraventricular nucleus of pubertal and adult male rats exposed to ethanol or control in utero. The functionality of transplanted BEP neurons was determined by measuring proopiomelanocortin (POMC) gene expression in these cells and their effects on CRH gene expression under basal and after lipopolysaccaride (LPS) challenge. In addition, the effectiveness of BEP neurons in activating NK cell functions is determined by measuring NK cell cytolytic activity and interferon-γ (IFN-γ) production in the spleen and in the peripheral blood mononuclear cell (PBMC) following cell transplantation. Results We showed here that when these in vitro differentiated BEP neurons were transplanted into the hypothalamus, they maintain biological functions by producing POMC and reducing the CRH neuronal response to the LPS challenge. BEP neuronal transplants significantly increased NK cell cytolytic activity in the spleen and in the PBMC and increased plasma levels of IFN-γ in control and fetal alcohol exposed rats. Conclusions These data further establish the BEP neuronal regulatory role in the control of CRH and NK cell cytolytic function and identify a possible novel therapy to treat stress hyper-response and immune deficiency in fetal alcohol exposed subjects. PMID:19320628
Jewett, Anahid; Cacalano, Nicholas A; Head, Christian; Teruel, Antonia
2006-04-01
Down-modulation of CD16 (FcgammaRIII) receptors and loss of natural killer (NK) cell function have been observed in oral cancer patients. However, neither the mechanisms nor the significance of the decrease in CD16 receptors have been fully understood. The cytotoxic activity and survival of NK cells are negatively regulated by antibodies directed against CD16 surface receptor. The addition of anti-CD94 antibody in combination with either F(ab')(2) fragment or intact anti-CD16 antibody to NK cells resulted in significant inhibition of NK cell cytotoxic function and induction of apoptosis in resting human peripheral blood NK cells. Addition of interleukin-2 to anti-CD16 and/or anti-CD94 antibody-treated NK cells significantly inhibited apoptosis and increased the function of NK cells. There was a significant increase in tumor necrosis factor-alpha (TNF-alpha) but not IFN-gamma secretion in NK cells treated either with anti-CD16 antibody alone or in combination with anti-CD94 antibodies. Consequently, the addition of anti-TNF-alpha antibody partially inhibited apoptosis of NK cells mediated by the combination of anti-CD94 and anti-CD16 antibodies. Increase in apoptotic death of NK cells also correlated with an increase in type 2 inflammatory cytokines and in the induction of chemokines. Thus, we conclude that binding of antibodies to CD16 and CD94 NK cell receptors induces death of the NK cells and signals for the release of chemokines.
Macrophage Polarization in Chronic Inflammatory Diseases: Killers or Builders?
Baci, Denisa; Tremolati, Marco; Fanuli, Matteo; Farronato, Giampietro; Mortara, Lorenzo
2018-01-01
Macrophages are key cellular components of the innate immunity, acting as the main player in the first-line defence against the pathogens and modulating homeostatic and inflammatory responses. Plasticity is a major feature of macrophages resulting in extreme heterogeneity both in normal and in pathological conditions. Macrophages are not homogenous, and they are generally categorized into two broad but distinct subsets as either classically activated (M1) or alternatively activated (M2). However, macrophages represent a continuum of highly plastic effector cells, resembling a spectrum of diverse phenotype states. Induction of specific macrophage functions is closely related to the surrounding environment that acts as a relevant orchestrator of macrophage functions. This phenomenon, termed polarization, results from cell/cell, cell/molecule interaction, governing macrophage functionality within the hosting tissues. Here, we summarized relevant cellular and molecular mechanisms driving macrophage polarization in “distant” pathological conditions, such as cancer, type 2 diabetes, atherosclerosis, and periodontitis that share macrophage-driven inflammation as a key feature, playing their dual role as killers (M1-like) and/or builders (M2-like). We also dissect the physio/pathological consequences related to macrophage polarization within selected chronic inflammatory diseases, placing polarized macrophages as a relevant hallmark, putative biomarkers, and possible target for prevention/therapy. PMID:29507865
Lee, Sung Won; Park, Hyun Jung; Kim, Nayoung; Hong, Seokmann
2013-01-01
Natural killer dendritic cells (NKDCs) possess potent anti-tumor activity, but the cellular effect of NKDC interactions with other innate immune cells is unclear. In this study, we demonstrate that the interaction of NKDCs and natural killer T (NKT) cells is required for the anti-tumor immune responses that are elicited by α -galactosylceramide ( α -GC) in mice. The rapid and strong expression of interferon- γ by NKDCs after α -GC stimulation was dependent on NKT cells. Various NK and DC molecular markers and cytotoxic molecules were up-regulated following α -GC administration. This up-regulation could improve NKDC presentation of tumor antigens and increase cytotoxicity against tumor cells. NKDCs were required for the stimulation of DCs, NK cells, and NKT cells. The strong anti-tumor immune responses elicited by α -GC may be due to the down-regulation of regulatory T cells. Furthermore, the depletion of NKDCs dampened the tumor clearance mediated by α -GC-stimulated NKT cells in vivo. Taken together, these results indicate that complex interactions of innate immune cells might be required to achieve optimal anti-tumor immune responses during the early stages of tumorigenesis.
(1-->6)-beta-D-glucan as cell wall receptor for Pichia membranifaciens killer toxin.
Santos, A; Marquina, D; Leal, J A; Peinado, J M
2000-05-01
The killer toxin from Pichia membranifaciens CYC 1106, a yeast isolated from fermenting olive brines, binds primarily to the (1-->6)-beta-D-glucan of the cell wall of a sensitive yeast (Candida boidinii IGC 3430). The (1-->6)-beta-D-glucan was purified from cell walls of C. boidinii by alkali and hot-acetic acid extraction, a procedure which solubilizes glucans. The major fraction of receptor activity remained with the alkali-insoluble (1-->6)-beta- and (1-->3)-beta-D-glucans. The chemical (gas-liquid chromatography) and structural (periodate oxidation, infrared spectroscopy, and (1)H nuclear magnetic resonance) analyses of the fractions obtained showed that (1-->6)-beta-D-glucan was a receptor. Adsorption of most of the killer toxin to the (1-->6)-beta-D-glucan was complete within 2 min. Killer toxin adsorption to the linear (1-->6)-beta-D-glucan, pustulan, and a glucan from Penicillium allahabadense was observed. Other polysaccharides with different linkages failed to bind the killer toxin. The specificity of the killer toxin for its primary receptor provides an effective means to purify the killer toxin, which may have industrial applications for fermentations in which salt is present as an adjunct, such as olive brines. This toxin shows its maximum killer activity in the presence of NaCl. This report is the first to identify the (1-->6)-beta-D-glucan as a receptor for this novel toxin.
Grosser, Katrin; Ramasamy, Pathmanaban; Amirabad, Azim Dehghani; Schulz, Marcel H; Gasparoni, Gilles; Simon, Martin
2018-01-01
Abstract Endosymbiosis is a widespread phenomenon and hosts of bacterial endosymbionts can be found all-over the eukaryotic tree of life. Likely, this evolutionary success is connected to the altered phenotype arising from a symbiotic association. The potential variety of symbiont’s contributions to new characteristics or abilities of host organisms are largely unstudied. Addressing this aspect, we focused on an obligate bacterial endosymbiont that confers an intraspecific killer phenotype to its host. The symbiosis between Paramecium tetraurelia and Caedibacter taeniospiralis, living in the host’s cytoplasm, enables the infected paramecia to release Caedibacter symbionts, which can simultaneously produce a peculiar protein structure and a toxin. The ingestion of bacteria that harbor both components leads to the death of symbiont-free congeners. Thus, the symbiosis provides Caedibacter-infected cells a competitive advantage, the “killer trait.” We characterized the adaptive gene expression patterns in symbiont-harboring Paramecium as a second symbiosis-derived aspect next to the killer phenotype. Comparative transcriptomics of infected P. tetraurelia and genetically identical symbiont-free cells confirmed altered gene expression in the symbiont-bearing line. Our results show up-regulation of specific metabolic and heat shock genes whereas down-regulated genes were involved in signaling pathways and cell cycle regulation. Functional analyses to validate the transcriptomics results demonstrated that the symbiont increases host density hence providing a fitness advantage. Comparative transcriptomics shows gene expression modulation of a ciliate caused by its bacterial endosymbiont thus revealing new adaptive advantages of the symbiosis. Caedibacter taeniospiralis apparently increases its host fitness via manipulation of metabolic pathways and cell cycle control. PMID:29390087
Conry, Sara J; Milkovich, Kimberly A; Yonkers, Nicole L; Rodriguez, Benigno; Bernstein, Helene B; Asaad, Robert; Heinzel, Frederick P; Tary-Lehmann, Magdalena; Lederman, Michael M; Anthony, Donald D
2009-11-01
Human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infections impair plasmacytoid dendritic cell (PDC) and natural killer (NK) cell subset numbers and functions, though little is known about PDC-NK cell interactions during these infections. We evaluated PDC-dependent NK cell killing and gamma interferon (IFN-gamma) and granzyme B production, using peripheral blood mononuclear cell (PBMC)-based and purified cell assays of samples from HCV- and HIV-infected subjects. CpG-enhanced PBMC killing and IFN-gamma and granzyme B activity (dependent on PDC and NK cells) were impaired in viremic HIV infection. In purified PDC-NK cell culture experiments, CpG-enhanced, PDC-dependent NK cell activity was cell contact and IFN-alpha dependent, and this activity was impaired in viremic HIV infection but not in HCV infection. In heterologous PDC-NK cell assays, impaired PDC-NK cell killing activity was largely attributable to an NK cell defect, while impaired PDC-NK cell IFN-gamma-producing activity was attributable to both PDC and NK cell defects. Additionally, the response of NK cells to direct IFN-alpha stimulation was defective in viremic HIV infection, and this defect was not attributable to diminished IFN-alpha receptor expression, though IFN-alpha receptor and NKP30 expression was closely associated with killer activity in viremic HIV infection but not in healthy controls. These data indicate that during uncontrolled HIV infection, PDC-dependent NK cell function is impaired, which is in large part attributable to defective IFN-alpha-induced NK cell activity and not to altered IFN-alpha receptor, NKP30, NKP44, NKP46, or NKG2D expression.
Interactions between human mesenchymal stem cells and natural killer cells.
Sotiropoulou, Panagiota A; Perez, Sonia A; Gritzapis, Angelos D; Baxevanis, Constantin N; Papamichail, Michael
2006-01-01
Mesenchymal stem cells (MSCs) are multipotent progenitor cells representing an attractive therapeutic tool for regenerative medicine. They possess unique immunomodulatory properties, being capable of suppressing T-cell responses and modifying dendritic cell differentiation, maturation, and function, whereas they are not inherently immunogenic, failing to induce alloreactivity to T cells and freshly isolated natural killer (NK) cells. To clarify the generation of host immune responses to implanted MSCs in tissue engineering and their potential use as immunosuppressive elements, the effect of MSCs on NK cells was investigated. We demonstrate that at low NK-to-MSC ratios, MSCs alter the phenotype of NK cells and suppress proliferation, cytokine secretion, and cyto-toxicity against HLA-class I- expressing targets. Some of these effects require cell-to-cell contact, whereas others are mediated by soluble factors, including transforming growth factor-beta1 and prostaglandin E2, suggesting the existence of diverse mechanisms for MSC-mediated NK-cell suppression. On the other hand, MSCs are susceptible to lysis by activated NK cells. Overall, these data improve our knowledge of interactions between MSCs and NK cells and consequently of their effect on innate immune responses and their contribution to the regulation of adaptive immunity, graft rejection, and cancer immunotherapy.
Cato, Anita; Celada, Lindsay; Kibakaya, Esther Caroline; Simmons, Nadia; Whalen, Margaret M
2014-12-01
Natural killer (NK) cells provide a vital surveillance against virally infected cells, tumor cells, and antibody-coated cells through the release of cytolytic mediators and gamma interferon (IFN-γ). Hexabromocyclododecane (HBCD) is a brominated flame retardant used primarily in expanded (EPS) and extruded (XPS) polystyrene foams for thermal insulation in the building and construction industry. Tetrabromobisphenol A (TBBPA) is used both as a reactive and an additive flame retardant in a variety of materials. HBCD and TBBPA contaminate the environment and are found in human blood samples. In previous studies, we have shown that other environmental contaminants, such as the dibutyltin (DBT) and tributyltin (TBT), decrease NK lytic function by activating mitogen-activated protein kinases (MAPKs) in the NK cells. HBCD and TBBPA also interfere with NK cell(s) lytic function. The current study evaluates whether HBCD and/or TBBPA have the capacity to activate MAPKs and MAPK kinases (MAP2Ks). The effects of concentrations of HBCD and TBBPA that inhibited lytic function on the phosphorylation state and total levels of the MAPKs (p44/42, p38, and JNK) and the phosphorylation and total levels of the MAP2Ks (MEK1/2 and MKK3/6) were examined. Results indicate that exposure of human NK cells to 10-0.5 μM HBCD or TBBPA activate MAPKs and MAP2Ks. This HBCD and TBBPA-induced activation of MAPKs may leave them unavailable for activation by virally infected or tumor target cells and thus contributes to the observed decreases in lytic function seen in NK cells exposed to HBCD and TBBPA.
Laginha, Inês; Kopp, Marcel A; Druschel, Claudia; Schaser, Klaus-Dieter; Brommer, Benedikt; Hellmann, Rick C; Watzlawick, Ralf; Ossami-Saidi, Ramin-Raul; Prüss, Harald; Failli, Vieri; Meisel, Christian; Liebscher, Thomas; Prilipp, Erik; Niedeggen, Andreas; Ekkernkamp, Axel; Grittner, Ulrike; Piper, Sophie K; Dirnagl, Ulrich; Killig, Monica; Romagnani, Chiara; Schwab, Jan M
2016-09-13
Natural killer (NK) cells comprise the main components of lymphocyte-mediated nonspecific immunity. Through their effector function they play a crucial role combating bacterial and viral challenges. They are also thought to be key contributors to the systemic spinal cord injury-induced immune-deficiency syndrome (SCI-IDS). SCI-IDS increases susceptibility to infection and extends to the post-acute and chronic phases after SCI. The prospective study of NK cell function after traumatic SCI was carried out in two centers in Berlin, Germany. SCI patients and control patients with neurologically silent vertebral fracture also undergoing surgical stabilization were enrolled. Furthermore healthy controls were included to provide reference data. The NK cell function was assessed at 7 (5-9) days, 14 days (11-28) days, and 10 (8-12) weeks post-trauma. Clinical documentation included the American Spinal Injury Association (ASIA) impairment scale (AIS), neurological level of injury, infection status, concomitant injury, and medications. The primary endpoint of the study is CD107a expression by NK cells (cytotoxicity marker) 8-12 weeks following SCI. Secondary endpoints are the NK cell's TNF-α and IFN-γ production by the NK cells 8-12 weeks following SCI. The protocol of this study was developed to investigate the hypotheses whether i) SCI impairs NK cell function throughout the post-acute and sub-acute phases after SCI and ii) the degree of impairment relates to lesion height and severity. A deeper understanding of the SCI-IDS is crucial to enable strategies for prevention of infections, which are associated with poor neurological outcome and elevated mortality. DRKS00009855 .
The Biology of Pichia membranifaciens Killer Toxins
Belda, Ignacio; Ruiz, Javier; Alonso, Alejandro; Marquina, Domingo; Santos, Antonio
2017-01-01
The killer phenomenon is defined as the ability of some yeast to secrete toxins that are lethal to other sensitive yeasts and filamentous fungi. Since the discovery of strains of Saccharomyces cerevisiae capable of secreting killer toxins, much information has been gained regarding killer toxins and this fact has substantially contributed knowledge on fundamental aspects of cell biology and yeast genetics. The killer phenomenon has been studied in Pichia membranifaciens for several years, during which two toxins have been described. PMKT and PMKT2 are proteins of low molecular mass that bind to primary receptors located in the cell wall structure of sensitive yeast cells, linear (1→6)-β-d-glucans and mannoproteins for PMKT and PMKT2, respectively. Cwp2p also acts as a secondary receptor for PMKT. Killing of sensitive cells by PMKT is characterized by ionic movements across plasma membrane and an acidification of the intracellular pH triggering an activation of the High Osmolarity Glycerol (HOG) pathway. On the contrary, our investigations showed a mechanism of killing in which cells are arrested at an early S-phase by high concentrations of PMKT2. However, we concluded that induced mortality at low PMKT2 doses and also PMKT is indeed of an apoptotic nature. Killer yeasts and their toxins have found potential applications in several fields: in food and beverage production, as biocontrol agents, in yeast bio-typing, and as novel antimycotic agents. Accordingly, several applications have been found for P. membranifaciens killer toxins, ranging from pre- and post-harvest biocontrol of plant pathogens to applications during wine fermentation and ageing (inhibition of Botrytis cinerea, Brettanomyces bruxellensis, etc.). PMID:28333108
New Directions for Natural Killer T Cells in the Immunotherapy of Cancer
Teyton, Luc
2017-01-01
Natural killer T (NKT) cells have been placed at the interface between innate and adaptive immunity by a long series of experiments that convincingly showed that beyond cytokine secretion and NK cell recruitment, NKT cells were coordinating dendritic cell and B cell maturation through direct membrane contacts and initiate productive responses. As such, NKT cells are the cellular adjuvant of many immune reactions and have functions that go much beyond what their name encapsulates. In addition, the initial discovery of the ligands of NKT cells is deeply linked to cancer biology and therapy. However, for a host of reasons, animal models in which agonists of NKT cells were used did not translate well to human cancers. A systematic reassessment of NKT cells role in tumorigenesis, especially spontaneous one, is now accessible using single cell analysis technologies both in mouse and man, and should be taken advantage of. Similarly, the migration, localization, phenotype of NKT cells following induced expansion after injection of an agonist can be examined at the single cell level. This technological revolution will help evaluate where and how NKT cells can be used in cancer. PMID:29209309
Role of natural killer cells in lung cancer.
Aktaş, Ozge Nur; Öztürk, Ayşe Bilge; Erman, Baran; Erus, Suat; Tanju, Serhan; Dilege, Şükrü
2018-06-01
One of the key immune cells involved in the pathogenesis of lung cancer is natural killer (NK) cells and these cells are novel targets for therapeutic applications in lung cancer. The purpose of this review is to summarize the current literature on lung cancer pathogenesis with a focus on the interaction between NK cells and smoking, how these factors are related to the pathogenesis of lung cancer and how NK cell-based immunotherapy effect lung cancer survival. The relevant literature from PubMed and Medline databases is reviewed in this article. The cytolytic potential of NK cells are reduced in lung cancer and increasing evidence suggests that improving NK cell functioning may induce tumor regression. Recent clinical trials on NK cell-based novel therapies such as cytokines including interleukin (IL)-15, IL-12 and IL-2, NK-92 cell lines and allogenic NK cell immunotherapy showed promising results with less adverse effects on the lung cancer survival. The NK cell targeting strategy has not yet been approved for lung cancer treatment. More clinical studies focusing on the role of NK cells in lung cancer pathogenesis are warranted to develop novel NK cell-based therapeutic approaches for the treatment of lung cancer.
Therapeutic Potential and Challenges of Natural Killer Cells in Treatment of Solid Tumors
Gras Navarro, Andrea; Björklund, Andreas T.; Chekenya, Martha
2015-01-01
Natural killer (NK) cells are innate lymphoid cells that hold tremendous potential for effective immunotherapy for a broad range of cancers. Due to the mode of NK cell killing, requiring one-to-one target engagement and site-directed release of cytolytic granules, the therapeutic potential of NK cells has been most extensively explored in hematological malignancies. However, their ability to precisely kill antibody coated cells, cancer stem cells, and genotoxically altered cells, while maintaining tolerance to healthy cells makes them appealing therapeutic effectors for all cancer forms, including metastases. Due to their release of pro-inflammatory cytokines, NK cells may potently reverse the anti-inflammatory tumor microenvironment (TME) and augment adaptive immune responses by promoting differentiation, activation, and/or recruitment of accessory immune cells to sites of malignancy. Nevertheless, integrated and coordinated mechanisms of subversion of NK cell activity against the tumor and its microenvironment exist. Although our understanding of the receptor ligand interactions that regulate NK cell functionality has evolved remarkably, the diversity of ligands and receptors is complex, as is their mechanistic foundations in regulating NK cell function. In this article, we review the literature and highlight how the TME manipulates the NK cell phenotypes, genotypes, and tropism to evade tumor recognition and elimination. We discuss counter strategies that may be adopted to augment the efficacy of NK cell anti-tumor surveillance, the clinical trials that have been undertaken so far in solid malignancies, critically weighing the challenges and opportunities with this approach. PMID:25972872
[Methods for increasing the immunogenicity of vaccines].
Kündig, T M
2000-09-14
In the past years, enormous efforts have been undertaken to develop vaccine strategies against cancer. The aim is to have the immune system generate what are called killer cells that can specifically recognize the tumor. The surface of tumor cells contains MHC/HLA antigens which present short-chain peptides of tumor specific antigens. A large number of these oligopeptide antigens have been characterized in recent years. They are now available for use as tumor-specific vaccines. The problem is, however, that the immune response of producing T killer cells is very inefficient when these oligopeptide antigens are injected. As the physiological function of these killer cells virus-infected cells, a process associated with substantial tissue damage, the immune system has learned to use these killer cells with reticence over the course of evolution, in other words, when the life of the host is threatened. This does not happen until pathogens start to spread via lymphogenous or hematogenous pathways. And then it takes a certain amount of time after the invader is present for replication to take place. Since the oligopeptide antigens used as vaccines have a very short half-life in the tissue, not enough of them get to the lymph nodes and stay there for enough time to efficiently induce an immune response. Using a mouse model, we were able to show that the efficiency of the vaccine can be increased a million-fold by directly injecting the vaccine into a lymph node or the spleen which imitates lymphogenous or hematogenous spread. The efficiency of the "inactivated vaccine" can be enhanced even more by continuous administration of the vaccine over several days, simulating an especially dangerous virus replication. The evidence gathered in this mouse model was transferred to a clinical trial. The melanoma-specific inactivated vaccine is infused directly into a lymph node of tumor patients. The infusion is continued for several days. Booster vaccines are given every two weeks.
Beitzen-Heineke, Antonia; Bouzani, Maria; Schmitt, Anna-Lena; Kurzai, Oliver; Hünniger, Kerstin; Einsele, Hermann; Loeffler, Juergen
2016-02-01
Aspergillus fumigatus is the most common cause for invasive fungal infections, a disease associated with high mortality in immune-compromised patients. CD1d-restricted invariant natural killer T (iNKT) cells compose a small subset of T cells known to impact the immune response toward various infectious pathogens. To investigate the role of human iNKT cells during A. fumigatus infection, we studied their activation as determined by CD69 expression and cytokine production in response to distinct fungal morphotypes in the presence of different CD1d(+) antigen presenting cells using flow cytometry and multiplex enzyme-linked immunosorbent assay (ELISA). Among CD1d(+) subpopulations, CD1d(+)CD1c(+) mDCs showed the highest potential to activate iNKT cells on a per cell basis. The presence of A. fumigatus decreased this effect of CD1d(+)CD1c(+) mDCs on iNKT cells and led to reduced secretion of TNF-α, G-CSF and RANTES. Production of other Th1 and Th2 cytokines was not affected by the fungus, suggesting an immune-modulating function for human iNKT cells during A. fumigatus infection. © The Author 2015. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Natural killer T-cell lymphoma of the tongue.
Cho, Kwang-Jae; Cho, Seok-Goo; Lee, Dong-Hee
2005-01-01
Lymphoma, which represents about 5.4% of all neoplasms and, more significantly, 19% to 28% of malignant neoplasms, is the most common nonepithelial malignancy of the head and neck area in Koreans. Natural killer T-cell (NK/T-cell) lymphoma is a lymphoma of putative natural killer cell lineage. NK/T-cell neoplasms are generally rare, but they are more common in people of East Asian, Mexican, or South American descent. These neoplasms are highly aggressive and show a strong association with Epstein-Barr virus. The preferential site of extranodal NK/T-cell lymphoma is the nasal cavity, and there has been no report of NK/T-cell lymphoma developing from the tongue. We encountered a rare case of NK/T-cell lymphoma of the tongue, which we report with a review of the literature.
[Functional activity of the natural killers and macrophages in patients with breast tumors].
Andrianov, I G; Voronov, S M; Dobkin, A N; Okulov, V B; Orlov, A B
1988-01-01
The activity of natural killers (NK) and macrophages of peripheral blood was studied in 37 female donors, 40 patients with benign and 43 with malignant tumors of the breast of various stages prior to treatment. Also the effect of Soviet-made recombinant interleukin-2 on NK activity was assessed. Natural killer activity (cytotoxic index) was 34.1 +/- 1.42 in healthy donors, 44.2 +/- 3.64 in cases of fibroadenomatosis, 43.1 +/- 5.6 in patients with stages I-IIa, 64.4 +/- 3.93--stage IIb, 45.8 +/- 6.32--stage III and 16.6 +/- 7.21% in cases of stage IV breast cancer, the scatter of values being greater in the tumor group. As many as 40% of patients with stages I-IIa and III cancer showed increased NK-activity values. An in vitro stimulating effect of NK activity of peripheral blood mononuclear cells by Soviet-made recombinant interleukin-2 was established.
Natural killer cell dysfunction in hepatocellular carcinoma and NK cell-based immunotherapy
Sun, Cheng; Sun, Hao-yu; Xiao, Wei-hua; Zhang, Cai; Tian, Zhi-gang
2015-01-01
The mechanisms linking hepatitis B virus (HBV) and hepatitis C virus (HCV) infection to hepatocellular carcinoma (HCC) remain largely unknown. Natural killer (NK) cells account for 25%–50% of the total number of liver lymphocytes, suggesting that NK cells play an important role in liver immunity. The number of NK cells in the blood and tumor tissues of HCC patients is positively correlated with their survival and prognosis. Furthermore, a group of NK cell-associated genes in HCC tissues is positively associated with the prolonged survival. These facts suggest that NK cells and HCC progression are strongly associated. In this review, we describe the abnormal NK cells and their functional impairment in patients with chronic HBV and HCV infection, which contribute to the progression of HCC. Then, we summarize the association of NK cells with HCC based on the abnormalities in the numbers and phenotypes of blood and liver NK cells in HCC patients. In particular, the exhaustion of NK cells that represents lower cytotoxicity and impaired cytokine production may serve as a predictor for the occurrence of HCC. Finally, we present the current achievements in NK cell immunotherapy conducted in mouse models of liver cancer and in clinical trials, highlighting how chemoimmunotherapy, NK cell transfer, gene therapy, cytokine therapy and mAb therapy improve NK cell function in HCC treatment. It is conceivable that NK cell-based anti-HCC therapeutic strategies alone or in combination with other therapies will be great promise for HCC treatment. PMID:26073325
Shah, Nina; Martin-Antonio, Beatriz; Yang, Hong; Ku, Stephanie; Lee, Dean A; Cooper, Laurence J N; Decker, William K; Li, Sufang; Robinson, Simon N; Sekine, Takuya; Parmar, Simrit; Gribben, John; Wang, Michael; Rezvani, Katy; Yvon, Eric; Najjar, Amer; Burks, Jared; Kaur, Indreshpal; Champlin, Richard E; Bollard, Catherine M; Shpall, Elizabeth J
2013-01-01
Natural killer (NK) cells are important mediators of anti-tumor immunity and are active against several hematologic malignancies, including multiple myeloma (MM). Umbilical cord blood (CB) is a promising source of allogeneic NK cells but large scale ex vivo expansion is required for generation of clinically relevant CB-derived NK (CB-NK) cell doses. Here we describe a novel strategy for expanding NK cells from cryopreserved CB units using artificial antigen presenting feeder cells (aAPC) in a gas permeable culture system. After 14 days, mean fold expansion of CB-NK cells was 1848-fold from fresh and 2389-fold from cryopreserved CB with >95% purity for NK cells (CD56(+)/CD3(-)) and less than 1% CD3(+) cells. Though surface expression of some cytotoxicity receptors was decreased, aAPC-expanded CB-NK cells exhibited a phenotype similar to CB-NK cells expanded with IL-2 alone with respect to various inhibitory receptors, NKG2C and CD94 and maintained strong expression of transcription factors Eomesodermin and T-bet. Furthermore, CB-NK cells formed functional immune synapses with and demonstrated cytotoxicity against various MM targets. Finally, aAPC-expanded CB-NK cells showed significant in vivo activity against MM in a xenogenic mouse model. Our findings introduce a clinically applicable strategy for the generation of highly functional CB-NK cells which can be used to eradicate MM.
Gunge, N; Murata, K; Sakaguchi, K
1982-01-01
Protoplasts of Saccharomyces cerevisiae were mixed with linear DNA plasmids, pGKl1 and pGKl2, isolated from a Kluyveromyces lactis killer strain and treated with polyethylene glycol. Out of 2,000 colonies regenerated on a nonselective medium, two killer transformants were obtained. The pGKl plasmids and the killer character were stably maintained in one (Pdh-1) of them. Another transformant, Pdl-1, was a weak killer, and the subclones consisted of a mixture of weak and nonkiller cells. The weak killers were characterized by the presence of pGKl1 in a decreased amount, and nonkillers were characterized by the absence of pGKl1. The occurrence of two new plasmids which migrated faster than pGKl1 in an agarose gel was observed in Pdl-1 and its subclones, whether weak or nonkillers. Staining with 4',6-diamidino-2-phenylindole revealed that the pGKl plasmids exist in the cytosol of transformant cells with numerous copy numbers. Images PMID:7045080
Wu, Zeguang; Sinzger, Christian; Frascaroli, Giada; Reichel, Johanna; Bayer, Carina; Wang, Li; Schirmbeck, Reinhold; Mertens, Thomas
2013-07-01
Recent studies indicate that expansion of NKG2C-positive natural killer (NK) cells is associated with human cytomegalovirus (HCMV); however, their activity in response to HCMV-infected cells remains unclear. We show that NKG2C(hi) CD57(hi) NK cells gated on CD3(neg) CD56(dim) cells can be phenotypically identified as HCMV-induced NK cells that can be activated by HCMV-infected cells. Using HCMV-infected autologous macrophages as targets, we were able to show that these NKG2C(hi) CD57(hi) NK cells are highly responsive to HCMV-infected macrophages only in the presence of HCMV-specific antibodies, whereas they are functionally poor effectors of natural cytotoxicity. We further demonstrate that NKG2C(hi) CD57(hi) NK cells are intrinsically responsive to signaling through CD16 cross-linking. Our findings show that the activity of pathogen-induced innate immune cells can be enhanced by adaptive humoral immunity. Understanding the activity of NKG2C(hi) CD57(hi) NK cells against HCMV-infected cells will be of relevance for the further development of adoptive immunotherapy.
The aryl hydrocarbon receptor is required for the maintenance of liver-resident natural killer cells
2016-01-01
A tissue-resident population of natural killer cells (NK cells) in the liver has recently been described to have the unique capacity to confer immunological memory in the form of hapten-specific contact hypersensitivity independent of T and B cells. Factors regulating the development and maintenance of these liver-resident NK cells are poorly understood. The aryl hydrocarbon receptor (AhR) is a transcription factor modulated by exogenous and endogenous ligands that is important in the homeostasis of immune cells at barrier sites, such as the skin and gut. In this study, we show that liver-resident NK (NK1.1+CD3−) cells, defined as CD49a+TRAIL+CXCR6+DX5− cells in the mouse liver, constitutively express AhR. In AhR−/− mice, there is a significant reduction in the proportion and absolute number of these cells, which results from a cell-intrinsic dependence on AhR. This deficiency in liver-resident NK cells appears to be the result of higher turnover and increased susceptibility to cytokine-induced cell death. Finally, we show that this deficiency has functional implications in vivo. Upon hapten exposure, AhR−/− mice are not able to mount an NK cell memory response to hapten rechallenge. Together, these data demonstrate the requirement of AhR for the maintenance of CD49a+TRAIL+CXCR6+DX5− liver-resident NK cells and their hapten memory function. PMID:27670593
Cruz, C. Russell; Bollard, Catherine M.
2015-01-01
Hematopoietic stem cell transplantation has revolutionized the treatment of hematologic malignancies, but infection, graft-versus-host disease and relapse are still important problems. Calcineurin inhibitors, T-cell depletion strategies, and immunomodulators have helped to prevent graft-versus-host disease, but have a negative impact on the graft-versus-leukemia effect. T cells and natural killer cells are both thought to be important in the graft-versus-leukemia effect, and both cell types are amenable to ex vivo manipulation and clinical manufacture, making them versatile immunotherapeutics. We provide an overview of these immunotherapeutic strategies following hematopoietic stem cell transplantation, with discussions centered on natural killer and T-cell biology. We discuss the contributions of each cell type to graft-versus-leukemia effects, as well as the current research directions in the field as related to adoptive cell therapy after hematopoietic stem cell transplantation. PMID:26034113
"Killer" Microcapsules That Can Selectively Destroy Target Microparticles in Their Vicinity.
Arya, Chandamany; Oh, Hyuntaek; Raghavan, Srinivasa R
2016-11-02
We have developed microscale polymer capsules that are able to chemically degrade a certain type of polymeric microbead in their immediate vicinity. The inspiration here is from the body's immune system, where killer T cells selectively destroy cancerous cells or cells infected by pathogens while leaving healthy cells alone. The "killer" capsules are made from the cationic biopolymer chitosan by a combination of ionic cross-linking (using multivalent tripolyposphate anions) and subsequent covalent cross-linking (using glutaraldehyde). During capsule formation, the enzyme glucose oxidase (GOx) is encapsulated in these capsules. The target beads are made by ionic cross-linking of the biopolymer alginate using copper (Cu 2+ ) cations. The killer capsules harvest glucose from their surroundings, which is then enzymatically converted by GOx into gluconate ions. These ions are known for their ability to chelate Cu 2+ cations. Thus, when a killer capsule is next to a target alginate bead, the gluconate ions diffuse into the bead and extract the Cu 2+ cross-links, causing the disintegration of the target bead. Such destruction is visualized in real-time using optical microscopy. The destruction is specific, i.e., other microparticles that do not contain Cu 2+ are left undisturbed. Moreover, the destruction is localized, i.e., the targets destroyed in the short term are the ones right next to the killer beads. The time scale for destruction depends on the concentration of encapsulated enzyme in the capsules.
Speak, Anneliese O.; te Vruchte, Danielle; Davis, Lianne C.; Morgan, Anthony J.; Smith, David A.; Yanjanin, Nicole M.; Simmons, Louise; Hartung, Ralf; Runz, Heiko; Mengel, Eugen; Beck, Michael; Imrie, Jackie; Jacklin, Elizabeth; Wraith, James E.; Hendriksz, Christian; Lachmann, Robin; Cognet, Celine; Sidhu, Rohini; Fujiwara, Hideji; Ory, Daniel S.; Galione, Antony; Porter, Forbes D.; Vivier, Eric
2014-01-01
Niemann-Pick type C (NPC) is a neurodegenerative lysosomal storage disorder caused by defects in the lysosomal proteins NPC1 or NPC2. NPC cells are characterized by reduced lysosomal calcium levels and impaired sphingosine transport from lysosomes. Natural killer (NK) cells kill virally infected/transformed cells via degranulation of lysosome-related organelles. Their trafficking from lymphoid tissues into the circulation is dependent on sphingosine-1-phosphate (S1P) gradients, sensed by S1P receptor 5 (S1P5). We hypothesized that NK-cell function and trafficking could be affected in NPC disease due to the combined effects of the lysosomal calcium defect and sphingosine storage. In an NPC1 mouse model, we found the frequency of NK cells was altered and phenocopied S1P5-deficient mice, consistent with defects in S1P levels. NK cells from NPC1 mice also had a defect in cytotoxicity due to a failure in degranulation of cytotoxic granules, which was associated with reduced lysosomal calcium levels. Affected NPC1 patients and NPC1 heterozygote carriers had reduced NK-cell numbers in their blood and showed similar phenotypic and developmental changes to those observed in the NPC1 mouse. These findings highlight the effects of lysosomal storage on the peripheral immune system. PMID:24235134
Nirmala, R; Narayanan, PR
2002-01-01
Background While dealing with mixed in vitro lymphocyte cultures one is faced with the problem of relative contributions of different populations to the activity being studied. This is especially true in the controversy relating to the contributions of lymphocyte sub-populations to the Lymphokine Activated Killer (LAK) phenomenon. Flowcytometry can be used to highlight relative contributions of lymphocyte subpopulations towards LAK activity without resorting to difficult purification strategies. We set up long-term in vitro lymphocyte cultures, stimulated them with cytokines IL-2/IL-12, recorded their phenotypic changes and cytotoxic activity against U-937 tumor targets. Results The results indicated that natural killer cells (NK) constituted the predominant proliferating cell population in the cytokine stimulatedcultures. Flowcytometric evidence revealed that CD56+ T cells contributed little to LAK activity against U937 target cells as compared to cells with NK phenotype which were predominantly responsible for spontaneous killing of the tumor targets. The two cytokines, IL-2 and IL-12, had an additive effect on cell proliferation and spontaneous cytotoxicity. Conclusion Flowcytometry can be used to rapidly delineate phenotypic changes in immune cells after stimulation and simultaneously correlate them with corresponding functional activity. This approach may find application as a initial screening tool for studying different types of cells in mixed cultures and their respective activities under stimulatory / inhibitory conditions. PMID:12165101
Dotiwala, Farokh; Sen Santara, Sumit; Binker-Cosen, Andres Ariel; Li, Bo; Chandrasekaran, Sriram; Lieberman, Judy
2017-11-16
Human cytotoxic lymphocytes kill intracellular microbes. The cytotoxic granule granzyme proteases released by cytotoxic lymphocytes trigger oxidative bacterial death by disrupting electron transport, generating superoxide anion and inactivating bacterial oxidative defenses. However, they also cause non-oxidative cell death because anaerobic bacteria are also killed. Here, we use differential proteomics to identify granzyme B substrates in three unrelated bacteria: Escherichia coli, Listeria monocytogenes, and Mycobacteria tuberculosis. Granzyme B cleaves a highly conserved set of proteins in all three bacteria, which function in vital biosynthetic and metabolic pathways that are critical for bacterial survival under diverse environmental conditions. Key proteins required for protein synthesis, folding, and degradation are also substrates, including multiple aminoacyl tRNA synthetases, ribosomal proteins, protein chaperones, and the Clp system. Because killer cells use a multipronged strategy to target vital pathways, bacteria may not easily become resistant to killer cell attack. Copyright © 2017 Elsevier Inc. All rights reserved.
O'Shea, Donal; Cawood, Tom J.; O'Farrelly, Cliona; Lynch, Lydia
2010-01-01
Background Obese individuals who smoke have a 14 year reduction in life expectancy. Both obesity and smoking are independantly associated with increased risk of malignancy. Natural killer cells (NK) are critical mediators of anti-tumour immunity and are compromised in obese patients and smokers. We examined whether NK cell function was differentially affected by cigarette smoke in obese and lean subjects. Methodology and Principal Findings Clinical data and blood were collected from 40 severely obese subjects (BMI>40 kg/m2) and 20 lean healthy subjects. NK cell levels and function were assessed using flow cytometry and cytotoxicity assays. The effect of cigarette smoke on NK cell ability to kill K562 tumour cells was assessed in the presence or absence of the adipokines leptin and adiponectin. NK cell levels were significantly decreased in obese subjects compared to lean controls (7.6 vs 16.6%, p = 0.0008). NK function was also significantly compromised in obese patients (30% +/− 13% vs 42% +/−12%, p = 0.04). Cigarette smoke inhibited NK cell ability to kill tumour cell lines (p<0.0001). NK cells from obese subjects were even more susceptible to the inhibitory effects of smoke compared to lean subjects (33% vs 28%, p = 0.01). Cigarette smoke prevented NK cell activation, as well as perforin and interferon-gamma secretion upon tumour challenge. Adiponectin but not leptin partially reversed the effects of smoke on NK cell function in both obese (p = 0.002) and lean controls (p = 0.01). Conclusions/Significance Obese subjects have impaired NK cell activity that is more susceptible to the detrimental effects of cigarette smoke compared to lean subjects. This may play a role in the increase of cancer and infection seen in this population. Adiponectin is capable of restoring NK cell activity and may have therapeutic potential for immunity in obese subjects and smokers. PMID:20107494
Bancos, Irina; Hazeldine, Jon; Chortis, Vasileios; Hampson, Peter; Taylor, Angela E; Lord, Janet M; Arlt, Wiebke
2017-04-01
Mortality in patients with primary adrenal insufficiency (PAI) is significantly increased, with respiratory infections as a major cause of death. Moreover, patients with PAI report an increased rate of non-fatal infections. Neutrophils and natural killer (NK) cells are innate immune cells that provide frontline protection against invading pathogens. Thus, we compared the function and phenotype of NK cells and neutrophils isolated from PAI patients and healthy controls to ascertain whether altered innate immune responses could be a contributory factor for the increased susceptibility of PAI patients to infection. We undertook a cross-sectional study of 42 patients with PAI due to autoimmune adrenalitis ( n = 37) or bilateral adrenalectomy ( n = 5) and 58 sex- and age-matched controls. A comprehensive screen of innate immune function, consisting of measurements of neutrophil phagocytosis, reactive oxygen species production, NK cell cytotoxicity (NKCC) and NK cell surface receptor expression, was performed on all subjects. Neutrophil function did not differ between PAI and controls. However, NKCC was significantly reduced in PAI (12.0 ± 1.5% vs 21.1 ± 2.6%, P < 0.0001). Phenotypically, the percentage of NK cells expressing the activating receptors NKG2D and NKp46 was significantly lower in PAI, as was the surface density of NKG2D (all P < 0.0001). Intracellular granzyme B expression was significantly increased in NK cells from PAI patients ( P < 0.01). Adrenal insufficiency is associated with significantly decreased NKCC, thereby potentially compromising early recognition and elimination of virally infected cells. This potential impairment in anti-viral immune defense may contribute to the increased rate of respiratory infections and ultimately mortality in PAI. © 2017 The authors.
Intrinsic hyporesponsiveness of invariant natural killer T cells precedes the onset of lupus
Yang, J-Q; Kim, P J; Halder, R C; Singh, R R
2013-01-01
Patients with systemic lupus erythematosus (SLE) display reduced numbers and functions of invariant natural killer T (iNK T) cells, which are restored upon treatment with corticosteroids and rituximab. It is unclear whether the iNK T cell insufficiency is a consequence of disease or is a primary abnormality that precedes the onset of disease. To address this, we analysed iNK T cell function at different stages of disease development using the genetically lupus-susceptible NZB × NZW F1 (BWF1) model. We found that iNK T cell in-vivo cytokine responses to an iNK T cell ligand α-galactosylceramide (α-GalCer) were lower in BWF1 mice than in non-autoimmune BALB/c and major histocompatibility complex (MHC)-matched NZB × N/B10.PL F1 mice, although iNK T cell numbers in the periphery were unchanged in BWF1 mice compared to control mice. Such iNK T cell hyporesponsiveness in BWF1 mice was detected at a young age long before the animals exhibited any sign of autoimmunity. In-vivo activation of iNK T cells is known to transactivate other immune cells. Such transactivated T and B cell activation markers and/or cytokine responses were also lower in BWF1 mice than in BALB/c controls. Finally, we show that iNK T cell responses were markedly deficient in the NZB parent but not in NZW parent of BWF1 mice, suggesting that BWF1 might inherit the iNK T cell defect from NZB mice. Thus, iNK T cells are functionally insufficient in lupus-prone BWF1 mice. Such iNK T cell insufficiency precedes the onset of disease and may play a pathogenic role during early stages of disease development in SLE. PMID:23607366
Mao, Hsiaoyin C.; Wei, Min; Hughes, Tiffany; Zhang, Jianying; Park, Il-kyoo; Liu, Shujun; McClory, Susan; Marcucci, Guido; Trotta, Rossana
2010-01-01
Human CD56bright natural killer (NK) cells possess little or no killer immunoglobulin-like receptors (KIRs), high interferon-γ (IFN-γ) production, but little cytotoxicity. CD56dim NK cells have high KIR expression, produce little IFN-γ, yet display high cytotoxicity. We hypothesized that, if human NK maturation progresses from a CD56bright to a CD56dim phenotype, an intermediary NK cell must exist, which demonstrates more functional overlap than these 2 subsets, and we used CD94 expression to test our hypothesis. CD94highCD56dim NK cells express CD62L, CD2, and KIR at levels between CD56bright and CD94lowCD56dim NK cells. CD94highCD56dim NK cells produce less monokine-induced IFN-γ than CD56bright NK cells but much more than CD94lowCD56dim NK cells because of differential interleukin-12–mediated STAT4 phosphorylation. CD94highCD56dim NK cells possess a higher level of granzyme B and perforin expression and CD94-mediated redirected killing than CD56bright NK cells but lower than CD94lowCD56dim NK cells. Collectively, our data suggest that the density of CD94 surface expression on CD56dim NK cells identifies a functional and likely developmental intermediary between CD56bright and CD94lowCD56dim NK cells. This supports the notion that, in vivo, human CD56bright NK cells progress through a continuum of differentiation that ends with a CD94lowCD56dim phenotype. PMID:19897577
Yu, Jianhua; Mao, Hsiaoyin C; Wei, Min; Hughes, Tiffany; Zhang, Jianying; Park, Il-kyoo; Liu, Shujun; McClory, Susan; Marcucci, Guido; Trotta, Rossana; Caligiuri, Michael A
2010-01-14
Human CD56(bright) natural killer (NK) cells possess little or no killer immunoglobulin-like receptors (KIRs), high interferon-gamma (IFN-gamma) production, but little cytotoxicity. CD56(dim) NK cells have high KIR expression, produce little IFN-gamma, yet display high cytotoxicity. We hypothesized that, if human NK maturation progresses from a CD56(bright) to a CD56(dim) phenotype, an intermediary NK cell must exist, which demonstrates more functional overlap than these 2 subsets, and we used CD94 expression to test our hypothesis. CD94(high)CD56(dim) NK cells express CD62L, CD2, and KIR at levels between CD56(bright) and CD94(low)CD56(dim) NK cells. CD94(high)CD56(dim) NK cells produce less monokine-induced IFN-gamma than CD56(bright) NK cells but much more than CD94(low)CD56(dim) NK cells because of differential interleukin-12-mediated STAT4 phosphorylation. CD94(high)CD56(dim) NK cells possess a higher level of granzyme B and perforin expression and CD94-mediated redirected killing than CD56(bright) NK cells but lower than CD94(low)CD56(dim) NK cells. Collectively, our data suggest that the density of CD94 surface expression on CD56(dim) NK cells identifies a functional and likely developmental intermediary between CD56(bright) and CD94(low)CD56(dim) NK cells. This supports the notion that, in vivo, human CD56(bright) NK cells progress through a continuum of differentiation that ends with a CD94(low)CD56(dim) phenotype.
Restoring Natural Killer Cell Immunity against Multiple Myeloma in the Era of New Drugs
Pittari, Gianfranco; Vago, Luca; Festuccia, Moreno; Bonini, Chiara; Mudawi, Deena; Giaccone, Luisa; Bruno, Benedetto
2017-01-01
Transformed plasma cells in multiple myeloma (MM) are susceptible to natural killer (NK) cell-mediated killing via engagement of tumor ligands for NK activating receptors or “missing-self” recognition. Similar to other cancers, MM targets may elude NK cell immunosurveillance by reprogramming tumor microenvironment and editing cell surface antigen repertoire. Along disease continuum, these effects collectively result in a progressive decline of NK cell immunity, a phenomenon increasingly recognized as a critical determinant of MM progression. In recent years, unprecedented efforts in drug development and experimental research have brought about emergence of novel therapeutic interventions with the potential to override MM-induced NK cell immunosuppression. These NK-cell enhancing treatment strategies may be identified in two major groups: (1) immunomodulatory biologics and small molecules, namely, immune checkpoint inhibitors, therapeutic antibodies, lenalidomide, and indoleamine 2,3-dioxygenase inhibitors and (2) NK cell therapy, namely, adoptive transfer of unmanipulated and chimeric antigen receptor-engineered NK cells. Here, we summarize the mechanisms responsible for NK cell functional suppression in the context of cancer and, specifically, myeloma. Subsequently, contemporary strategies potentially able to reverse NK dysfunction in MM are discussed. PMID:29163516
Natural killer/T-cell lymphoma invading the orbit and globe.
Lyons, Lance J; Vrcek, Ivan; Somogyi, Marie; Taheri, Kevin; Admirand, Joan H; Chexal, Saradha; Loukas, Demetrius F; Nakra, Tanuj
2017-10-01
Natural killer/T-cell lymphomas are extremely rare and carry high mortality rates. Epidemiologically, these cancers tend to affect mainly Asian and South American patients and are associated with Epstein-Barr virus seropositivity. This report details a 78-year-old Vietnamese woman who presented initially with vitritis of unknown cause, but later developed proptosis and conjunctival involvement as her disease spread. Biopsies of the orbit, ethmoid sinus, and conjunctiva were found to be significant for natural killer/T-cell lymphoma. The case highlights the diagnostic difficulty of this tumor given its rarity and ability to mimic other disorders.
Natural killer/T-cell lymphoma invading the orbit and globe
Lyons, Lance J.; Somogyi, Marie; Taheri, Kevin; Admirand, Joan H.; Chexal, Saradha; Loukas, Demetrius F.; Nakra, Tanuj
2017-01-01
Natural killer/T-cell lymphomas are extremely rare and carry high mortality rates. Epidemiologically, these cancers tend to affect mainly Asian and South American patients and are associated with Epstein-Barr virus seropositivity. This report details a 78-year-old Vietnamese woman who presented initially with vitritis of unknown cause, but later developed proptosis and conjunctival involvement as her disease spread. Biopsies of the orbit, ethmoid sinus, and conjunctiva were found to be significant for natural killer/T-cell lymphoma. The case highlights the diagnostic difficulty of this tumor given its rarity and ability to mimic other disorders. PMID:28966461
TdKT, a new killer toxin produced by Torulaspora delbrueckii effective against wine spoilage yeasts.
Villalba, María Leticia; Susana Sáez, Julieta; Del Monaco, Silvana; Lopes, Christian Ariel; Sangorrín, Marcela Paula
2016-01-18
Microbiological spoilage is a major concern throughout the wine industry, and control tools are limited. This paper addresses the identification and partial characterization of a new killer toxin from Torulaspora delbrueckii with potential biocontrol activity of Brettanomyces bruxellensis, Pichia guilliermondii, Pichia manshurica and Pichia membranifaciens wine spoilage. A panel of 18 different wine strains of T. delbrueckii killer yeasts was analysed, and the strain T. delbrueckii NPCC 1033 (TdKT producer) showed a significant inhibitory effect on the growth of all different spoilage yeasts evaluated. The TdKT toxin was then subjected to a partial biochemical characterization. Its estimated molecular weight was N30 kDa and it showed glucanase and chitinase enzymatic activities. The killer activity was stable between pH 4.2 and 4.8 and inactivated at temperature above 40 °C. Pustulan and chitin — but not other cell wall polysaccharides — prevented sensitive yeast cells from being killed by TdKT, suggesting that those may be the first toxin targets in the cell wall. TdKT provoked an increase in necrosis cell death after 3 h treatment and apoptotic cell death after 24 h showing time dependence in its mechanisms of action. Killer toxin extracts were active at oenological conditions, confirming their potential use as a biocontrol tool in winemaking.
Activation of cell-mediated immunity by Morinda citrifolia fruit extract and its constituents.
Murata, Kazuya; Abe, Yumi; Futamura-Masudaa, Megumi; Uwaya, Akemi; Isami, Fumiyuki; Matsuda, Hideaki
2014-04-01
Morinda citrifolia, commonly known as noni, is a traditional natural medicine in French Polynesia and Hawaii. Functional foods derived from M. citrifolia fruit have been marketed to help prevent diseases and promote good health. The objective of this study was to assess the effects of M. citrifolia fruit on cell-mediated immunity. In the picryl chloride-induced contact dermatitis test, M. citrifolia fruit extract (Noni-ext) inhibited the suppression of cell-mediated immunity by immunosuppressive substances isolated from freeze-dried ascites of Ehrlich carcinoma-bearing mice (EC-sup). In addition, Noni-ext inhibited reduction of IL-2 production in EC-sup-treated mice and activated natural killer cells in normal mice. These results suggest that Noni-ext has multiple effects on the recovery of cell-mediated immunity. Furthermore, we investigated the active principles of Noni-ext and identified an iridoid glycoside, deacetylasperulosidic acid. Oral administration of deacetylasperulosidic acid inhibited the reduction of ear swelling, and also cancelled the suppression of IL-2 production along with the activation of natural killer cells in the same manner as that of Noni-ext.
Harms, Robert Z.; Creer, Austin J.; Lorenzo-Arteaga, Kristina M.; Ostlund, Katie R.; Sarvetnick, Nora E.
2017-01-01
The cytokine interleukin (IL)-18 is a crucial amplifier of natural killer (NK) cell function. IL-18 signaling is regulated by the inhibitory effects of IL-18 binding protein (IL-18BP). Using mice deficient in IL-18BP (IL-18BPKO), we investigated the impact of mismanaged IL-18 signaling on NK cells. We found an overall reduced abundance of splenic NK cells in the absence of IL-18BP. Closer examination of NK cell subsets in spleen and bone marrow using CD27 and CD11b expression revealed that immature NK cells were increased in abundance, while the mature population of NK cells was reduced. Also, NK cells were polarized to greater production of TNF-α, while dedicated IFN-γ producers were reduced. A novel subset of IL-18 receptor α− NK cells contributed to the expansion of immature NK cells in IL-18BPKO mice. Splenocytes cultured with IL-18 resulted in alterations similar to those observed in IL-18BP deficiency. NK cell changes were associated with significantly reduced levels of circulating plasma IL-18. However, IL-18BPKO mice exhibited normal weight gain and responded to LPS challenge with a >10-fold increase in IFN-γ compared to wild type. Finally, we identified that the source of splenic IL-18BP was among dendritic cells/macrophage localized to the T cell-rich regions of the spleen. Our results demonstrate that IL-18BP is required for normal NK cell abundance and function and also contributes to maintaining steady-state levels of circulating IL-18. Thus, IL-18BP appears to have functions suggestive of a carrier protein, not just an inhibitor. PMID:28900426
High folic acid intake reduces natural killer cell cytotoxicity in aged mice
USDA-ARS?s Scientific Manuscript database
Presence of unmetabolized folic acid in plasma, which is indicative of folic acid intake beyond the metabolic capacity of the body, is associated with reduced natural killer (NK) cell cytotoxicity in post-menopausal women >/= 50 years. NK cells are cytotoxic lymphocytes that are part of the innate i...
Pesce, Silvia; Greppi, Marco; Tabellini, Giovanna; Rampinelli, Fabio; Parolini, Silvia; Olive, Daniel; Moretta, Lorenzo; Moretta, Alessandro; Marcenaro, Emanuela
2017-01-01
Programmed death 1 (PD-1) is an immunologic checkpoint that limits immune responses by delivering potent inhibitory signals to T cells on interaction with specific ligands expressed on tumor/virus-infected cells, thus contributing to immune escape mechanisms. Therapeutic PD-1 blockade has been shown to mediate tumor eradication with impressive clinical results. Little is known about the expression/function of PD-1 on human natural killer (NK) cells. We sought to clarify whether human NK cells can express PD-1 and analyze their phenotypic/functional features. We performed multiparametric cytofluorimetric analysis of PD-1 + NK cells and their functional characterization using degranulation, cytokine production, and proliferation assays. We provide unequivocal evidence that PD-1 is highly expressed (PD-1 bright ) on an NK cell subset detectable in the peripheral blood of approximately one fourth of healthy subjects. These donors are always serologically positive for human cytomegalovirus. PD-1 is expressed by CD56 dim but not CD56 bright NK cells and is confined to fully mature NK cells characterized by the NKG2A - KIR + CD57 + phenotype. Proportions of PD-1 bright NK cells were higher in the ascites of a cohort of patients with ovarian carcinoma, suggesting their possible induction/expansion in tumor environments. Functional analysis revealed a reduced proliferative capability in response to cytokines, low degranulation, and impaired cytokine production on interaction with tumor targets. We have identified and characterized a novel subpopulation of human NK cells expressing high levels of PD-1. These cells have the phenotypic characteristics of fully mature NK cells and are increased in patients with ovarian carcinoma. They display low proliferative responses and impaired antitumor activity that can be partially restored by antibody-mediated disruption of PD-1/programmed death ligand interaction. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.
Costa, Delfina; Venè, Roberta; Benelli, Roberto; Romairone, Emanuele; Scabini, Stefano; Catellani, Silvia; Rebesco, Barbara; Mastracci, Luca; Grillo, Federica; Minghelli, Simona; Loiacono, Fabrizio; Zocchi, Maria Raffaella; Poggi, Alessandro
2018-01-01
Mesenchymal stromal cells (MSC) present in the tumor microenvironment [usually named tumor-associated fibroblasts (TAF)] can exert immunosuppressive effects on T and natural killer (NK) lymphocytes, favoring tumor immune escape. We have analyzed this mechanism in colorectal carcinoma (CRC) and found that co-culture of NK cells with TAF can prevent the IL-2-mediated NKG2D upregulation. This leads to the impairment of NKG2D-mediated recognition of CRC cells, sparing the NK cell activation through DNAM1 or FcγRIIIA (CD16). In situ, TAF express detectable levels of epidermal growth factor receptor (EGFR); thus, the therapeutic anti-EGFR humanized antibody cetuximab can trigger the antibody-dependent cellular cytotoxicity of TAF, through the engagement of FcγRIIIA on NK cells. Importantly, in the tumor, we found a lymphoid infiltrate containing NKp46+CD3− NK cells, enriched in CD16+ cells. This population, sorted and cultured with IL-2, could be triggered via CD16 and via NKG2D. Of note, ex vivo NKp46+CD3− cells were able to kill autologous TAF; in vivo, this might represent a control mechanism to reduce TAF-mediated regulatory effect on NK cell function. Altogether, these findings suggest that MSC from the neoplastic mucosa (TAF) of CRC patients can downregulate the immune cell recognition of CRC tumor cells. This immunosuppression can be relieved by the anti-EGFR antibody used in CRC immunotherapy. PMID:29910806
Role for early-differentiated natural killer cells in infectious mononucleosis
Azzi, Tarik; Lünemann, Anna; Murer, Anita; Ueda, Seigo; Béziat, Vivien; Malmberg, Karl-Johan; Staubli, Georg; Gysin, Claudine; Berger, Christoph; Münz, Christian
2014-01-01
A growing body of evidence suggests that the human natural killer (NK)-cell compartment is phenotypically and functionally heterogeneous and is composed of several differentiation stages. Moreover, NK-cell subsets have been shown to exhibit adaptive immune features during herpes virus infection in experimental mice and to expand preferentially during viral infections in humans. However, both phenotype and role of NK cells during acute symptomatic Epstein-Barr virus (EBV) infection, termed infectious mononucleosis (IM), remain unclear. Here, we longitudinally assessed the kinetics, the differentiation, and the proliferation of subsets of NK cells in pediatric IM patients. Our results indicate that acute IM is characterized by the preferential proliferation of early-differentiated CD56dim NKG2A+ immunoglobulin-like receptor- NK cells. Moreover, this NK-cell subset exhibits features of terminal differentiation and persists at higher frequency during at least the first 6 months after acute IM. Finally, we demonstrate that this NK-cell subset preferentially degranulates and proliferates on exposure to EBV-infected B cells expressing lytic antigens. Thus, early-differentiated NK cells might play a key role in the immune control of primary infection with this persistent tumor-associated virus. PMID:25205117
Role for early-differentiated natural killer cells in infectious mononucleosis.
Azzi, Tarik; Lünemann, Anna; Murer, Anita; Ueda, Seigo; Béziat, Vivien; Malmberg, Karl-Johan; Staubli, Georg; Gysin, Claudine; Berger, Christoph; Münz, Christian; Chijioke, Obinna; Nadal, David
2014-10-16
A growing body of evidence suggests that the human natural killer (NK)-cell compartment is phenotypically and functionally heterogeneous and is composed of several differentiation stages. Moreover, NK-cell subsets have been shown to exhibit adaptive immune features during herpes virus infection in experimental mice and to expand preferentially during viral infections in humans. However, both phenotype and role of NK cells during acute symptomatic Epstein-Barr virus (EBV) infection, termed infectious mononucleosis (IM), remain unclear. Here, we longitudinally assessed the kinetics, the differentiation, and the proliferation of subsets of NK cells in pediatric IM patients. Our results indicate that acute IM is characterized by the preferential proliferation of early-differentiated CD56(dim) NKG2A(+) immunoglobulin-like receptor(-) NK cells. Moreover, this NK-cell subset exhibits features of terminal differentiation and persists at higher frequency during at least the first 6 months after acute IM. Finally, we demonstrate that this NK-cell subset preferentially degranulates and proliferates on exposure to EBV-infected B cells expressing lytic antigens. Thus, early-differentiated NK cells might play a key role in the immune control of primary infection with this persistent tumor-associated virus. © 2014 by The American Society of Hematology.
ID’ing Innate and Innate-like Lymphoid Cells
Verykokakis, Mihalis; Zook, Erin C.; Kee, Barbara L.
2014-01-01
Summary The immune system can be divided into innate and adaptive components that differ in their rate and mode of cellular activation, with innate immune cells being the first responders to invading pathogens. Recent advances in the identification and characterization of innate lymphoid cells have revealed reiterative developmental programs that result in cells with effector fates that parallel those of adaptive lymphoid cells and are tailored to effectively eliminate a broad spectrum of pathogenic challenges. However, activation of these cells can also be associated with pathologies such as autoimmune disease. One major distinction between innate and adaptive immune system cells is the constitutive expression of ID proteins in the former and inducible expression in the latter. ID proteins function as antagonists of the E protein transcription factors that play critical roles in lymphoid specification as well as B and T-lymphocyte development. In this review, we examine the transcriptional mechanisms controlling the development of innate lymphocytes, including natural killer cells and the recently identified innate lymphoid cells (ILC1, ILC2, and ILC3), and innate-like lymphocytes, including natural killer T cells, with an emphasis on the known requirements for the ID proteins. PMID:25123285
ID'ing innate and innate-like lymphoid cells.
Verykokakis, Mihalis; Zook, Erin C; Kee, Barbara L
2014-09-01
The immune system can be divided into innate and adaptive components that differ in their rate and mode of cellular activation, with innate immune cells being the first responders to invading pathogens. Recent advances in the identification and characterization of innate lymphoid cells have revealed reiterative developmental programs that result in cells with effector fates that parallel those of adaptive lymphoid cells and are tailored to effectively eliminate a broad spectrum of pathogenic challenges. However, activation of these cells can also be associated with pathologies such as autoimmune disease. One major distinction between innate and adaptive immune system cells is the constitutive expression of ID proteins in the former and inducible expression in the latter. ID proteins function as antagonists of the E protein transcription factors that play critical roles in lymphoid specification as well as B- and T-lymphocyte development. In this review, we examine the transcriptional mechanisms controlling the development of innate lymphocytes, including natural killer cells and the recently identified innate lymphoid cells (ILC1, ILC2, and ILC3), and innate-like lymphocytes, including natural killer T cells, with an emphasis on the known requirements for the ID proteins. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Clustered carbohydrates as a target for natural killer cells: a model system.
Kovalenko, Elena I; Abakushina, Elena; Telford, William; Kapoor, Veena; Korchagina, Elena; Khaidukov, Sergei; Molotkovskaya, Irina; Sapozhnikov, Alexander; Vlaskin, Pavel; Bovin, Nicolai
2007-03-01
Membrane-associated oligosaccharides are known to take part in interactions between natural killer (NK) cells and their targets and modulate NK cell activity. A model system was therefore developed using synthetic glycoconjugates as tools to modify the carbohydrate pattern on NK target cell surfaces. NK cells were then assessed for function in response to synthetic glycoconjugates, using both cytolysis-associated caspase 6 activation measured by flow cytometry and IFN-gamma production. Lipophilic neoglycoconjugates were synthesized to provide their easy incorporation into the target cell membranes and to make carbohydrate residues available for cell-cell interactions. While incorporation was successful based on fluorescence monitoring, glycoconjugate incorporation did not evoke artifactual changes in surface antigen expression, and had no negative effect on cell viability. Glycoconjugates contained Le(x), sulfated Le(x), and Le(y) sharing the common structure motif trisaccharide Le(x) were revealed to enhance cytotoxicity mediated specifically by CD16 +CD56+NK cells. The glycoconjugate effects were dependent on saccharide presentation in a polymeric form. Only polymeric, or clustered, but not monomeric glycoconjugates resulted in alteration of cytotoxicity in our system, suggesting that appropriate presentation is critical for carbohydrate recognition and subsequent biological effects.
One approach to cancer immunotherapy, as opposed to therapeutic vaccination, is the transfusion of large numbers of tumor-specific killer T cells (cytotoxic T cells or CTLs) into patients. The body’s own defense killer T cells are a subgroup of T lymphocytes (a type of white blood cells) that are capable of inducing death in tumor cells. CTLs can cause the death of target
USDA-ARS?s Scientific Manuscript database
Chicken natural killer (NK) cells are not well defined, so little is known about the molecular interactions controlling their activity. At day 14 of embryonic development, chick spleens are a rich source of T-cellfree CD8aa+, CD3_ cells with natural killing activity. Cell-mediated cytotoxicity assay...
Silva-Santos, Bruno; Strid, Jessica
2018-01-01
Natural killer cell receptors (NKRs) are germline-encoded transmembrane proteins that regulate the activation and homeostasis of NK cells as well as other lymphocytes. For γδ T cells, NKRs play critical roles in discriminating stressed (transformed or infected) cells from their healthy counterparts, as proposed in the "lymphoid stress-surveillance" theory. Whereas the main physiologic role is seemingly fulfilled by natural killer group 2 member D, constitutively expressed by γδ T cells, enhancement of their therapeutic potential may rely on natural cytotoxicity receptors (NCRs), like NKp30 or NKp44, that can be induced selectively on human Vδ1 + T cells. Here, we review the contributions of NCRs, NKG2D, and their multiple ligands, to γδ T cell biology in mouse and human.
Chauveau, Anne; Aucher, Anne; Eissmann, Philipp; Vivier, Eric; Davis, Daniel M.
2010-01-01
Membrane nanotubes are membranous tethers that physically link cell bodies over long distances. Here, we present evidence that nanotubes allow human natural killer (NK) cells to interact functionally with target cells over long distances. Nanotubes were formed when NK cells contacted target cells and moved apart. The frequency of nanotube formation was dependent on the number of receptor/ligand interactions and increased on NK cell activation. Most importantly, NK cell nanotubes contained a submicron scale junction where proteins accumulated, including DAP10, the signaling adaptor that associates with the activating receptor NKG2D, and MHC class I chain-related protein A (MICA), a cognate ligand for NKG2D, as occurs at close intercellular synapses between NK cells and target cells. Quantitative live-cell fluorescence imaging suggested that MICA accumulated at small nanotube synapses in sufficient numbers to trigger cell activation. In addition, tyrosine-phosphorylated proteins and Vav-1 accumulated at such junctions. Functionally, nanotubes could aid the lysis of distant target cells either directly or by moving target cells along the nanotube path into close contact for lysis via a conventional immune synapse. Target cells moving along the nanotube path were commonly polarized such that their uropods faced the direction of movement. This is the opposite polarization than for normal cell migration, implying that nanotubes can specifically drive target cell movement. Finally, target cells that remained connected to an NK cell by a nanotube were frequently lysed, whereas removing the nanotube using a micromanipulator reduced lysis of these target cells. PMID:20212116
Chen, Chi-Fang; Chu, Che-Yu; Chen, Te-Hao; Lee, Shyh-Jye; Shen, Chia-Ning; Hsiao, Chung-Der
2011-01-01
Background Zebrafish skin is composed of enveloping and basal layers which form a first-line defense system against pathogens. Zebrafish epidermis contains ionocytes and mucous cells that aid secretion of acid/ions or mucous through skin. Previous studies demonstrated that fish skin is extremely sensitive to external stimuli. However, little is known about the molecular mechanisms that modulate skin cell apoptosis in zebrafish. Methodology/Principal Findings This study aimed to create a platform to conduct conditional skin ablation and determine if it is possible to attenuate apoptotic stimuli by overexpressing potential apoptosis modulating genes in the skin of live animals. A transgenic zebrafish line of Tg(krt4:NTR-hKikGR)cy17 (killer line), which can conditionally trigger apoptosis in superficial skin cells, was first established. When the killer line was incubated with the prodrug metrodinazole, the superficial skin displayed extensive apoptosis as judged by detection of massive TUNEL- and active caspase 3-positive signals. Great reductions in NTR-hKikGR+ fluorescent signals accompanied epidermal cell apoptosis. This indicated that NTR-hKikGR+ signal fluorescence can be utilized to evaluate apoptotic events in vivo. After removal of metrodinazole, the skin integrity progressively recovered and NTR-hKikGR+ fluorescent signals gradually restored. In contrast, either crossing the killer line with testing lines or transiently injecting the killer line with testing vectors that expressed human constitutive active Akt1, mouse constitutive active Stat3, or HPV16 E6 element displayed apoptosis-resistant phenotypes to cytotoxic metrodinazole as judged by the loss of reduction in NTR-hKikGR+ fluorescent signaling. Conclusion/Significance The killer/testing line binary system established in the current study demonstrates a nitroreductase/metrodinazole system that can be utilized to conditionally perform skin ablation in a real-time manner, and provides a valuable tool to visualize and quantify the anti-apoptotic potential of interesting target genes in vivo. The current work identifies a potential use for transgenic zebrafish as a high-throughput platform to validate potential apoptosis modulators in vivo. PMID:21655190
SHP-2 expression negatively regulates NK cell function1,2
Purdy, Amanda K.; Campbell, Kerry S.
2009-01-01
Src homology region 2-containing protein tyrosine phosphatase-2 (SHP-2)4 is required for full activation of Ras/ERK in many cytokine and growth factor receptor signaling pathways. In contrast, SHP-2 inhibits activation of human natural killer (NK) cells upon recruitment to killer cell Ig-like receptors (KIR)4. To determine how SHP-2 impacts NK cell activation in KIR-dependent or KIR-independent signaling pathways, we employed knockdown and overexpression strategies in NK-like cell lines and analyzed the consequences on functional responses. In response to stimulation with susceptible target cells, SHP-2-silenced NK cells had elevated cytolytic activity and IFN-γ production, whereas cells overexpressing wild type or gain-of-function mutants of SHP-2 exhibited dampened activities. Increased levels of SHP-2 expression over this range significantly suppressed microtubule organizing center (MTOC)4 polarization and granzyme B release in response to target cells. Interestingly, NK-target cell conjugation was only reduced by overexpressing SHP-2, but not potentiated in SHP-2-silenced cells, indicating that conjugation is not influenced by physiological levels of SHP-2 expression. KIR-dependent inhibition of cytotoxicity was unaffected by significant reductions in SHP-2 levels, presumably because KIR were still capable of recruiting the phosphatase under these limiting conditions. In contrast, the general suppressive effect of SHP-2 on cytotoxicity and cytokine release was much more sensitive to changes in cellular SHP-2 levels. In summary, our studies have identified a new, KIR-independent role for SHP-2 in dampening NK cell activation in response to tumor target cells in a concentration-dependent manner. This suppression of activation impacts MTOC-based cytoskeletal rearrangement and granule release. PMID:19915046
Kim, Bo Kyung; Hong, Kyung Taek; Kang, Hyoung Jin; An, Hong Yul; Choi, Jung Yoon; Hong, Che Ry; Park, Kyung Duk; Lee, Dong Soon; Shin, Hee Young
2018-06-08
Epstein-Barr virus (EBV)-positive aggressive natural killer-cell leukemia (ANKL) is a rare malignancy of mature natural killer cells, with a very poor survival rate. Patients have a rapidly declining clinical course and a poor prognosis, with a median survival of only a few months. Herein, we describe a 16-year-old boy who was diagnosed with EBV-positive ANKL and successfully treated using combination chemotherapy and a subsequent allogeneic hematopoietic stem cell transplantation (alloHSCT). The patient is disease free 4 years and 9 months after alloHSCT. Thus, combination chemotherapy followed by alloHSCT seems to be a promising therapeutic option for EBV-positive ANKL.
Borrego, Francisco; Ulbrecht, Matthias; Weiss, Elisabeth H.; Coligan, John E.; Brooks, Andrew G.
1998-01-01
Human histocompatibility leukocyte antigen (HLA)-E is a nonclassical HLA class I molecule, the gene for which is transcribed in most tissues. It has recently been reported that this molecule binds peptides derived from the signal sequence of HLA class I proteins; however, no function for HLA-E has yet been described. We show that natural killer (NK) cells can recognize target cells expressing HLA-E molecules on the cell surface and this interaction results in inhibition of the lytic process. Furthermore, HLA-E recognition is mediated primarily through the CD94/NKG2-A heterodimer, as CD94-specific, but not killer cell inhibitory receptor (KIR)–specific mAbs block HLA-E–mediated protection of target cells. Cell surface HLA-E could be increased by incubation with synthetic peptides corresponding to residues 3–11 from the signal sequences of a number of HLA class I molecules; however, only peptides which contained a Met at position 2 were capable of conferring resistance to NK-mediated lysis, whereas those having Thr at position 2 had no effect. Interestingly, HLA class I molecules previously correlated with CD94/NKG2 recognition all have Met at residue 4 of the signal sequence (position 2 of the HLA-E binding peptide), whereas those which have been reported not to interact with CD94/NKG2 have Thr at this position. Thus, these data show a function for HLA-E and suggest an alternative explanation for the apparent broad reactivity of CD94/NKG2 with HLA class I molecules; that CD94/NKG2 interacts with HLA-E complexed with signal sequence peptides derived from “protective” HLA class I alleles rather than directly interacting with classical HLA class I proteins. PMID:9480992
Velázquez, Rocío; Zamora, Emiliano; Álvarez, Manuel; Álvarez, María L; Ramírez, Manuel
2016-10-01
The quality of traditional sparkling-wine depends on the aging process in the presence of dead yeast cells. These cells undergo a slow autolysis process thereby releasing some compounds, mostly colloidal polymers such as polysaccharides and mannoproteins, which influence the wine's foam properties and mouthfeel. Saccharomyces cerevisiae killer yeasts were tested to increase cell death and autolysis during mixed-yeast-inoculated second fermentation and aging. These yeasts killed sensitive strains in killer plate assays done under conditions of low pH and temperature similar to those used in sparkling-wine making, although some strains showed a different killer behaviour during the second fermentation. The fast killer effect improved the foam quality and mouthfeel of the mixed-inoculated wines, while the slow killer effect gave small improvements over single-inoculated wines. The effect was faster under high-pressure than under low-pressure conditions. Wine quality improvement did not correlate with the polysaccharide, protein, mannan, or aromatic compound concentrations, suggesting that the mouthfeel and foaming quality of sparkling wine are very complex properties influenced by other wine compounds and their interactions, as well as probably by the specific chemical composition of a given wine. Copyright © 2016 Elsevier Ltd. All rights reserved.
Sarkar, Dipak K; Sengupta, Amitabha; Zhang, Changqing; Boyadjieva, Nadka; Murugan, Sengottuvelan
2012-05-11
In the natural killer (NK) cells, δ-opiate receptor (DOR) and μ-opioid receptor (MOR) interact in a feedback manner to regulate cytolytic function with an unknown mechanism. Using RNK16 cells, a rat NK cell line, we show that MOR and DOR monomer and dimer proteins existed in these cells and that chronic treatment with a receptor antagonist reduced protein levels of the targeted receptor but increased levels of opposing receptor monomer and homodimer. The opposing receptor-enhancing effects of MOR and DOR antagonists were abolished following receptor gene knockdown by siRNA. Ethanol treatment increased MOR and DOR heterodimers while it decreased the cellular levels of MOR and DOR monomers and homodimers. The opioid receptor homodimerization was associated with an increased receptor binding, and heterodimerization was associated with a decreased receptor binding and the production of cytotoxic factors. Similarly, in vivo, opioid receptor dimerization, ligand binding of receptors, and cell function in immune cells were promoted by chronic treatment with an opiate antagonist but suppressed by chronic ethanol feeding. Additionally, a combined treatment of an MOR antagonist and a DOR agonist was able to reverse the immune suppressive effect of ethanol and reduce the growth and progression of mammary tumors in rats. These data identify a role of receptor dimerization in the mechanism of DOR and MOR feedback interaction in NK cells, and they further elucidate the potential for the use of a combined opioid antagonist and agonist therapy for the treatment of immune incompetence and cancer and alcohol-related diseases.
Wong, Emily S W; Sanderson, Claire E; Deakin, Janine E; Whittington, Camilla M; Papenfuss, Anthony T; Belov, Katherine
2009-08-01
Natural killer (NK) cell receptors belong to two unrelated, but functionally analogous gene families: the immunoglobulin superfamily, situated in the leukocyte receptor complex (LRC) and the C-type lectin superfamily, located in the natural killer complex (NKC). Here, we describe the largest NK receptor gene expansion seen to date. We identified 213 putative C-type lectin NK receptor homologs in the genome of the platypus. Many have arisen as the result of a lineage-specific expansion. Orthologs of OLR1, CD69, KLRE, CLEC12B, and CLEC16p genes were also identified. The NKC is split into at least two regions of the genome: 34 genes map to chromosome 7, two map to a small autosome, and the remainder are unanchored in the current genome assembly. No NK receptor genes from the LRC were identified. The massive C-type lectin expansion and lack of Ig-domain-containing NK receptors represents the most extreme polarization of NK receptors found to date. We have used this new data from platypus to trace the possible evolutionary history of the NK receptor clusters.
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.
Co-evolution of MHC class I and variable NK cell receptors in placental mammals.
Guethlein, Lisbeth A; Norman, Paul J; Hilton, Hugo G; Parham, Peter
2015-09-01
Shaping natural killer (NK) cell functions in human immunity and reproduction are diverse killer cell immunoglobulin-like receptors (KIRs) that recognize polymorphic MHC class I determinants. A survey of placental mammals suggests that KIRs serve as variable NK cell receptors only in certain primates and artiodactyls. Divergence of the functional and variable KIRs in primates and artiodactyls predates placental reproduction. Among artiodactyls, cattle but not pigs have diverse KIRs. Catarrhine (humans, apes, and Old World monkeys) and platyrrhine (New World monkeys) primates, but not prosimians, have diverse KIRs. Platyrrhine and catarrhine systems of KIR and MHC class I are highly diverged, but within the catarrhines, a stepwise co-evolution of MHC class I and KIR is discerned. In Old World monkeys, diversification focuses on MHC-A and MHC-B and their cognate lineage II KIR. With evolution of C1-bearing MHC-C from MHC-B, as informed by orangutan, the focus changes to MHC-C and its cognate lineage III KIR. Evolution of C2 from C1 and fixation of MHC-C drove further elaboration of MHC-C-specific KIR, as exemplified by chimpanzee. In humans, the evolutionary trajectory changes again. Emerging from reorganization of the KIR locus and selective attenuation of KIR avidity for MHC class I are the functionally distinctive KIR A and KIR B haplotypes. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
O’Sullivan, Timothy E.; Sun, Joseph C.; Lanier, Lewis L.
2015-01-01
Natural killer (NK) cells have historically been considered short-lived cytolytic cells that can rapidly respond against pathogens and tumors in an antigen-independent manner, and then undergo cell death. Recently, however, NK cells have been shown to possess traits of adaptive immunity, and can acquire immunological memory in a similar manner to T and B cells. In this review, we discuss evidence for NK cell memory and the mechanisms involved in the generation and survival of these innate lymphocytes. PMID:26488815
Large-scale ex vivo expansion and characterization of natural killer cells for clinical applications
LAPTEVA, NATALIA; DURETT, APRIL G.; SUN, JIALI; ROLLINS, LISA A.; HUYE, LESLIE L.; FANG, JIAN; DANDEKAR, VARADA; MEI, ZHUYONG; JACKSON, KIMBERLEY; VERA, JUAN; ANDO, JUN; NGO, MINHTRAN C.; COUSTAN-SMITH, ELAINE; CAMPANA, DARIO; SZMANIA, SUSANN; GARG, TARUN; MORENO-BOST, AMBERLY; VANRHEE, FRITS; GEE, ADRIAN P.; ROONEY, CLIONA M.
2016-01-01
Background aims Interest in natural killer (NK) cell-based immunotherapy has resurged since new protocols for the purification and expansion of large numbers of clinical-grade cells have become available. Methods We have successfully adapted a previously described NK expansion method that uses K562 cells expressing interleukin (IL)-15 and 4-1 BB Ligand (BBL) (K562-mb15-41BBL) to grow NK cells in novel gas-permeable static cell culture flasks (G-Rex). Results Using this system we produced up to 19 × 109 functional NK cells from unseparated apheresis products, starting with 15 × 107 CD3− CD56+ NK cells, within 8–10 days of culture. The G-Rex yielded a higher fold expansion of NK cells than conventional gas-permeable bags and required no cell manipulation or feeding during the culture period. We also showed that K562-mb15-41BBL cells up-regulated surface HLA class I antigen expression upon stimulation with the supernatants from NK cultures and stimulated alloreactive CD8+ T cells within the NK cultures. However, these CD3+ T cells could be removed successfully using the CliniMACS system. We describe our optimized NK cell cryopreservation method and show that the NK cells are viable and functional even after 12 months of cryopreservation. Conclusions We have successfully developed a static culture protocol for large-scale expansion of NK cells in the gas permeable G-Rex system under good manufacturing practice (GMP) conditions. This strategy is currently being used to produce NK cells for cancer immunotherapy. PMID:22900959
Histaminergic regulation of natural killer cell-mediated clearance of tumour cells in mice.
Asea, A; Hermodsson, S; Hellstrand, K
1996-01-01
Treatment of Swiss albino mice with histamine enhanced the clearance of natural killer (NK)-cell sensitive YAC-1 lymphoma and B16/F10 melanoma cells from lung tissue in vivo, but did not affect the elimination of NK-cell-insensitive P815 mastocytoma cells. The effect of histamine was apparently mediated by H2-type histamine receptors (H2R) since it was blocked by ranitidine, and H2R antagonist. Histamine did not affect clearance of tumour cells in animals depleted of NK cells in vivo by treatment with antibodies to asialo-GM1 or NK1.1. The effect of histamine was time-dependent: pretreatment with histamine for 3 h significantly augmented the clearance of YAC-1 cells, whereas, pretreatment with histamine for 5 min was ineffective. Histamine potentiated the anti-tumour properties of NK-cell activators such as interleukin-2 (IL-2) or interferon-alpha (IFN-alpha) in vivo. None of these lymphokines significantly affected the clearance of YAC-1 cells unless animals were concomitantly treated with histamine. Treatment with ranitidine alone reduced the in vivo clearance of YAC-1 cells from lungs but did not affect the clearance of NK-cell-insensitive P815 cells. Effects of ranitidine on NK-cell function in vivo were not shared by a chemical control to ranitidine, AH20239AA, thus indicating that the inhibition of NK-cells results from H2R antagonism rather than non-specific toxicity. It is concluded that histaminergic mechanisms may be involved in the regulation of NK cell function in vivo.
The adaptor protein Crk controls activation and inhibition of natural killer cells.
Liu, Dongfang; Peterson, Mary E; Long, Eric O
2012-04-20
Natural killer (NK) cell inhibitory receptors recruit tyrosine phosphatases to prevent activation, induce phosphorylation and dissociation of the small adaptor Crk from cytoskeleton scaffold complexes, and maintain NK cells in a state of responsiveness to subsequent activation events. How Crk contributes to inhibition is unknown. We imaged primary NK cells over lipid bilayers carrying IgG1 Fc to stimulate CD16 and human leukocyte antigen (HLA)-E to inhibit through receptor CD94-NKG2A. HLA-E alone induced Crk phosphorylation in NKG2A(+) NK cells. At activating synapses with Fc alone, Crk was required for the movement of Fc microclusters and their ability to trigger activation signals. At inhibitory synapses, HLA-E promoted central accumulation of both Fc and phosphorylated Crk and blocked the Fc-induced buildup of F-actin. We propose a unified model for inhibitory receptor function: Crk phosphorylation prevents essential Crk-dependent activation signals and blocks F-actin network formation, thereby reducing constraints on subsequent engagement of activation receptors. Copyright © 2012 Elsevier Inc. All rights reserved.
Adaptive NKG2C+CD57+ Natural Killer Cell and Tim-3 Expression During Viral Infections
Kared, Hassen; Martelli, Serena; Tan, Shu Wen; Simoni, Yannick; Chong, Meng Li; Yap, Siew Hwei; Newell, Evan W.; Pender, Sylvia L. F.; Kamarulzaman, Adeeba; Rajasuriar, Reena; Larbi, Anis
2018-01-01
Repetitive stimulation by persistent pathogens such as human cytomegalovirus (HCMV) or human immunodeficiency virus (HIV) induces the differentiation of natural killer (NK) cells. This maturation pathway is characterized by the acquisition of phenotypic markers, CD2, CD57, and NKG2C, and effector functions—a process regulated by Tim-3 and orchestrated by a complex network of transcriptional factors, involving T-bet, Eomes, Zeb2, promyelocytic leukemia zinc finger protein, and Foxo3. Here, we show that persistent immune activation during chronic viral co-infections (HCMV, hepatitis C virus, and HIV) interferes with the functional phenotype of NK cells by modulating the Tim-3 pathway; a decrease in Tim-3 expression combined with the acquisition of inhibitory receptors skewed NK cells toward an exhausted and cytotoxic phenotype in an inflammatory environment during chronic HIV infection. A better understanding of the mechanisms underlying NK cell differentiation could aid the identification of new immunological targets for checkpoint blockade therapies in a manner that is relevant to chronic infection and cancer. PMID:29731749
Hughes, Tiffany; Becknell, Brian; McClory, Susan; Briercheck, Edward; Freud, Aharon G.; Zhang, Xiaoli; Mao, Hsiaoyin; Nuovo, Gerard; Yu, Jianhua
2009-01-01
Considerable functional heterogeneity within human natural killer (NK) cells has been revealed through the characterization of distinct NK-cell subsets. Accordingly, a small subset of CD56+NKp44+NK cells, termed NK-22 cells, was recently described within secondary lymphoid tissue (SLT) as IL-22− when resting, with a minor fraction of this population becoming IL-22+ when activated. Here we discover that the vast majority of stage 3 immature NK (iNK) cells in SLT constitutively and selectively express IL-22, a TH17 cytokine important for mucosal immunity, whereas earlier and later stages of NK developmental intermediates do not express IL-22. These iNK cells have a surface phenotype of CD34−CD117+CD161+CD94−, largely lack expression of NKp44 and CD56, and do not produce IFN-γ or possess cytolytic activity. In summary, stage 3 iNK cells are highly enriched for IL-22 and IL-26 messenger RNA, and IL-22 protein production, but do not express IL-17A or IL-17F. PMID:19244159
The up side of decidual natural killer cells: new developments in immunology of pregnancy.
Jabrane-Ferrat, Nabila; Siewiera, Johan
2014-04-01
Early phases of human pregnancy are associated with the accumulation of a unique subset of natural killer (NK) cells in the maternal decidua. Decidual NK (dNK) cells that are devoid of cytotoxicity play a pivotal role in successful pregnancy. By secreting large amounts of cytokines/chemokines and angiogenic factors, dNK cells participate in all steps of placentation including trophoblast invasion into the maternal endometrium and vascular remodelling. In this review, we summarize some of dNK cell features and discuss more recent exciting data that challenge the conventional view of these cells. Our new data demonstrate that dNK cells undergo fine tuning or even subvert their classical inhibitory machinery and turn into a real defence force in order to prevent the spread of viruses to fetal tissue. Today it is not clear how these phenotypic and functional adaptations impact cellular cross-talk at the fetal-maternal interface and tissue homeostasis. Ultimately, precise understanding of the molecular mechanisms that govern dNK cell plasticity during congenital human cytomegalovirus infection should lead to the design of more robust strategies to reverse immune escape during viral infection and cancer. © 2013 John Wiley & Sons Ltd.
Molecular definition of the identity and activation of natural killer cells.
Bezman, Natalie A; Kim, Charles C; Sun, Joseph C; Min-Oo, Gundula; Hendricks, Deborah W; Kamimura, Yosuke; Best, J Adam; Goldrath, Ananda W; Lanier, Lewis L
2012-10-01
Using whole-genome microarray data sets of the Immunological Genome Project, we demonstrate a closer transcriptional relationship between NK cells and T cells than between any other leukocytes, distinguished by their shared expression of genes encoding molecules with similar signaling functions. Whereas resting NK cells are known to share expression of a few genes with cytotoxic CD8(+) T cells, our transcriptome-wide analysis demonstrates that the commonalities extend to hundreds of genes, many encoding molecules with unknown functions. Resting NK cells demonstrate a 'preprimed' state compared with naive T cells, which allows NK cells to respond more rapidly to viral infection. Collectively, our data provide a global context for known and previously unknown molecular aspects of NK cell identity and function by delineating the genome-wide repertoire of gene expression of NK cells in various states.
Montoya, Carlos J; Pollard, David; Martinson, Jeffrey; Kumari, Kumud; Wasserfall, Clive; Mulder, Candice B; Rugeles, Maria T; Atkinson, Mark A; Landay, Alan L; Wilson, S Brian
2007-09-01
Identification of human CD1d-restricted T-cell receptor (TCR)-invariant natural killer T (iNKT) cells has been dependent on utilizing combinations of monoclonal antibodies or CD1d tetramers, which do not allow for the most specific analysis of this T-cell subpopulation. A novel monoclonal antibody (clone 6B11), specific for the invariant CDR3 loop of human canonical Valpha24Jalpha18 TCR alpha chain, was developed and used to specifically characterize iNKT cells. In healthy individuals studied for up to 1 year, a wide but stable frequency of circulating iNKT cells (range: 0.01-0.92%) was observed, with no differences in frequency by gender. Four stable iNKT cell subsets were characterized in peripheral blood based on the expression of CD4 and CD8, with CD8(+) iNKT cells being a phenotypic and functionally different subset from CD4(+) and double negative iNKT cells; in particular, LAG-3 was preferentially expressed on CD8(+) iNKT cells. In addition, a strong negative linear correlation between the frequency of total iNKT cells and percentage of the CD4(+) subset was observed. In terms of their potential association with disease, patients at risk for type 1 diabetes had significantly expanded frequencies of double negative iNKT cells when compared to matched controls and first-degree relatives. Moreover, peripheral blood CD4(+) iNKT cells were the highest producers of interleukin-4, while the production of interferon-gamma and tumour necrosis factor-alpha was similar amongst all iNKT cell subsets. These differences in iNKT cell subsets suggest that in humans the relative ratio of iNKT cell subsets may influence susceptibility vs. resistance to immune-mediated diseases.
Montoya, Carlos J; Pollard, David; Martinson, Jeffrey; Kumari, Kumud; Wasserfall, Clive; Mulder, Candice B; Rugeles, Maria T; Atkinson, Mark A; Landay, Alan L; Wilson, S Brian
2007-01-01
Identification of human CD1d-restricted T-cell receptor (TCR)-invariant natural killer T (iNKT) cells has been dependent on utilizing combinations of monoclonal antibodies or CD1d tetramers, which do not allow for the most specific analysis of this T-cell subpopulation. A novel monoclonal antibody (clone 6B11), specific for the invariant CDR3 loop of human canonical Vα24Jα18 TCR α chain, was developed and used to specifically characterize iNKT cells. In healthy individuals studied for up to 1 year, a wide but stable frequency of circulating iNKT cells (range: 0·01–0·92%) was observed, with no differences in frequency by gender. Four stable iNKT cell subsets were characterized in peripheral blood based on the expression of CD4 and CD8, with CD8+ iNKT cells being a phenotypic and functionally different subset from CD4+ and double negative iNKT cells; in particular, LAG-3 was preferentially expressed on CD8+ iNKT cells. In addition, a strong negative linear correlation between the frequency of total iNKT cells and percentage of the CD4+ subset was observed. In terms of their potential association with disease, patients at risk for type 1 diabetes had significantly expanded frequencies of double negative iNKT cells when compared to matched controls and first-degree relatives. Moreover, peripheral blood CD4+ iNKT cells were the highest producers of interleukin-4, while the production of interferon-γ and tumour necrosis factor-α was similar amongst all iNKT cell subsets. These differences in iNKT cell subsets suggest that in humans the relative ratio of iNKT cell subsets may influence susceptibility vs. resistance to immune-mediated diseases. PMID:17662044
Abraha, Abraham B; Rana, Krupa; Whalen, Margaret M
2010-11-01
Human natural killer (NK) cells are lymphocytes that destroy tumor and virally infected cells. Previous studies have shown that exposure of NK cells to tributyltin (TBT) greatly diminishes their ability to destroy tumor cells (lytic function) while activating mitogen-activated protein kinases (MAPK) (p44/42, p38, and JNK) in NK cells. The signaling pathway that regulates NK lytic function appears to include activation of protein kinase C(PKC) as well as MAPK activity. TBT-induced activation of MAPKs would trigger a portion of the NK lytic signaling pathway, which would then leave the NK cell unable to trigger this pathway in response to a subsequent encounter with a target cell. In the present study we evaluated the involvement of PKC in inhibition of NK lysis of tumor cells and activation of MAPKs caused by TBT exposure. TBT caused a 2–3-fold activation of PKC at concentrations ranging from 50 to 300 nM (16–98 ng/ml),indicating that activation of PKC occurs in response to TBT exposure. This would then leave the NK cell unable to respond to targets. Treatment with the PKC inhibitor, bisindolylmaleimide I, caused an 85% decrease in the ability of NK cells to lyse tumor cells, validating the involvement of PKC in the lytic signaling pathway. The role of PKC in the activation of MAPKs by TBT was also investigated using bisindolylmaleimide I. The results indicated that, in NK cells where PKC activation was blocked, there was no activation of the MAPK, p44/42 in response to TBT.However, TBT-induced activation of the MAPKs, p38 and JNK did not require PKC activation. These results indicate the pivotal role of PKC in the TBT-induced loss of NK lytic function including activation of p44/42 by TBT in NK cells.
Abraha, Abraham B.; Rana, Krupa; Whalen, Margaret M.
2010-01-01
Human natural killer (NK) cells are lymphocytes that destroy tumor and virally infected cells. Previous studies have shown that exposures of NK cells to tributyltin (TBT) greatly diminish their ability to destroy tumor cells (lytic function) while activating mitogen-activated protein kinases (MAPK) (p44/42, p38, and JNK) in the NK cells. The signaling pathway that regulates NK lytic function appears to include activation of protein kinase C (PKC) as well as MAPK activity. The TBT-induced activation of MAPKs would trigger a portion of the NK lytic signaling pathway, which would then leave the NK cell unable to trigger this pathway in response to a subsequent encounter with a target cell. In the present study we evaluated the involvement of PKC in the inhibition of NK lysis of tumor cells and activation of MAPKs caused by TBT exposures. TBT caused a 2–3 fold activation of PKC at concentrations ranging from 50–300 nM (16–98 ng/mL), indicating that activation of PKC occurs in response to TBT exposures. This would then leave the NK cell unable to respond to targets. Treatment with the PKC inhibitor, bisindolylmaleimide I, caused an 85% decrease in the ability of NK cells to lyse tumor cells validating the involvement of PKC in the lytic signaling pathway. The role of PKC in the activation of MAPKs by TBT was also investigated using bisindolylmaleimide I. The results indicated that in NK cells where PKC activation was blocked there was no activation of the MAPK, p44/42 in response to TBT. However, TBT-induced activation of the MAPKs, p38 and JNK did not require PKC activation. These results indicate the pivotal role of PKC in the TBT-induced loss of NK lytic function including the activation of p44/42 by TBT in NK cells. PMID:20390410
Recognition of peptide–MHC class I complexes by activating killer immunoglobulin-like receptors
Stewart, C. Andrew; Laugier-Anfossi, Fanny; Vély, Frédéric; Saulquin, Xavier; Riedmuller, Jenifer; Tisserant, Agnès; Gauthier, Laurent; Romagné, François; Ferracci, Géraldine; Arosa, Fernando A.; Moretta, Alessandro; Sun, Peter D.; Ugolini, Sophie; Vivier, Eric
2005-01-01
Inhibitory receptors for MHC class I molecules increase the threshold of lymphocyte activation. Natural Killer (NK) cells express a large number of such inhibitory receptors, including the human killer Ig-like receptors (KIR). However, activating members of the KIR family have poorly defined ligands and functions. Here we describe the use of activating KIR tetramer reagents as probes to detect their ligands. Infection of cells with Epstein–Barr virus leads to expression of a detectable ligand for the activating receptor KIR2DS1. In this case, KIR2DS1 interacts with up-regulated peptide–MHC class I complexes on Epstein–Barr virus-infected cells in a transporter associated with antigen processing (TAP)-dependent manner. In tetramer-based cellular assays and direct affinity measurements, this interaction with MHC class I is facilitated by a broad spectrum of peptides. KIR2DS1 and its inhibitory homologue, KIR2DL1, share sensitivity to peptide sequence alterations at positions 7 and 8. These results fit a model in which activating and inhibitory receptors recognize the same sets of self-MHC class I molecules, differing only in their binding affinities. Importantly, KIR2DS1 is not always sufficient to trigger NK effector responses when faced with cognate ligand, consistent with fine control during NK cell activation. We discuss how our results for KIR2DS1 and parallel studies on KIR2DS2 relate to the association between activating KIR genes and susceptibility to autoimmune disorders. PMID:16141329
Recognition of peptide-MHC class I complexes by activating killer immunoglobulin-like receptors.
Stewart, C Andrew; Laugier-Anfossi, Fanny; Vély, Frédéric; Saulquin, Xavier; Riedmuller, Jenifer; Tisserant, Agnès; Gauthier, Laurent; Romagné, François; Ferracci, Géraldine; Arosa, Fernando A; Moretta, Alessandro; Sun, Peter D; Ugolini, Sophie; Vivier, Eric
2005-09-13
Inhibitory receptors for MHC class I molecules increase the threshold of lymphocyte activation. Natural Killer (NK) cells express a large number of such inhibitory receptors, including the human killer Ig-like receptors (KIR). However, activating members of the KIR family have poorly defined ligands and functions. Here we describe the use of activating KIR tetramer reagents as probes to detect their ligands. Infection of cells with Epstein-Barr virus leads to expression of a detectable ligand for the activating receptor KIR2DS1. In this case, KIR2DS1 interacts with up-regulated peptide-MHC class I complexes on Epstein-Barr virus-infected cells in a transporter associated with antigen processing (TAP)-dependent manner. In tetramer-based cellular assays and direct affinity measurements, this interaction with MHC class I is facilitated by a broad spectrum of peptides. KIR2DS1 and its inhibitory homologue, KIR2DL1, share sensitivity to peptide sequence alterations at positions 7 and 8. These results fit a model in which activating and inhibitory receptors recognize the same sets of self-MHC class I molecules, differing only in their binding affinities. Importantly, KIR2DS1 is not always sufficient to trigger NK effector responses when faced with cognate ligand, consistent with fine control during NK cell activation. We discuss how our results for KIR2DS1 and parallel studies on KIR2DS2 relate to the association between activating KIR genes and susceptibility to autoimmune disorders.
Rapidly fatal nasal natural killer/T-cell lymphoma: orbital and ocular adnexal presentations.
Yousuf, Salman J; Kumar, Nitin; Kidwell, Earl D; Copeland, Robert A
2011-03-01
Nasal natural killer/T-cell lymphoma (NKTL) is an aggressive malignancy that may initially present with orbital and/or ocular adnexal symptoms. We describe the case of a 27-year-old female with nasal NKTL, who initially presented with epiphora and died 4 months thereafter.
de Matos, Cristina Teixeira; Berg, Louise; Michaëlsson, Jakob; Felländer-Tsai, Li; Kärre, Klas; Söderström, Kalle
2007-01-01
Natural killer (NK) cells are activated early during inflammatory events and contribute to the shaping of the ensuing adaptive immune response. To further understand the role for NK cells in inflammation, we investigated the phenotype and function of synovial fluid (SF) NK cells from patients with chronic joint inflammation, as well as from patients with transient inflammation of the knee following trauma. We confirm that synovial NK cells are similar to the well-characterized CD56bright peripheral blood (PB) NK-cell subset present in healthy individuals. However, compared to this PB subset the synovial NK cells express a higher degree of activation markers including CD69 and NKp44, the latter being up-regulated also on CD56bright NK cells in the PB of patients. Activated synovial NK cells produced interferon-γ and tumour necrosis factor, and the production was further up-regulated by antibody masking of CD94/NKG2A, and down-regulated by target cells expressing human leucocyte antigen-E in complex with peptides known to engage CD94/NKG2A. We conclude that synovial NK cells have an activated phenotype and that CD94/NKG2A is a key regulator of synovial NK-cell cytokine synthesis. PMID:17521371
Celada, Lindsay J.; Whalen, Margaret M.
2013-01-01
Butyltins (BTs) contaminate the environment and are found in human blood. BTs, tributyltin (TBT) and dibutyltin (DBT), diminish the cytotoxic function and levels of key proteins of human natural killer (NK) cells. NK cells are an initial immune defense against tumors, virally-infected cells and antibody-coated cells and thus critical to human health. The signaling pathways that regulate NK cell functions include mitogen-activated protein kinases (MAPKs). Studies have shown that exposure to BTs leads to the activation of specific MAPKs and MAPK kinases (MAP2Ks) in human NK cells. MAP2K kinases (MAP3Ks) are upstream activators of MAP2Ks, which then activate MAPKs. The current study examined if BT-induced activation of MAP3Ks was responsible for MAP2K and thus, MAPK activation. This study examines the effects of TBT and DBT on the total levels of two MAP3Ks, c-Raf and ASK1, as well as activating and inhibitory phosphorylation sites on these MAP3Ks. In addition, the immediate upstream activator of c-Raf, Ras, was examined for BT-induced alterations. Our results show significant activation of the MAP3K, c-Raf, in human NK cells within 10 minutes of TBT exposure and the MAP3K, ASK1, after one hour exposures to TBT. In addition, our results suggest that both TBT and DBT are impacting the regulation of c-Raf. PMID:24038145
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 future.
Dudimah, Fred D.; Abraha, Abraham; Wang, Xiaofei; Whalen, Margaret M.
2010-01-01
Tributyltin (TBT) activates the mitogen activated protein kinase (MAPK), p44/42 in human natural killer (NK) cells. TBT also reduces NK cytotoxic function and decreases the expression of several NK-cell proteins. To understand the role that p44/42 activation plays in TBT-induced loss of NK cell function, we have investigated how selective activation of p44/42 by phorbol 12-myristate 13-acetate (PMA) affects NK cells. Previously we showed that PMA caused losses of lytic function similar to those seen with TBT exposures. Here we examined activation of p44/42 in the regulation of NK-cell protein expression and how this regulation may explain the protein expression changes seen with TBT exposures. NK cells exposed to PMA were examined for levels of cell-surface proteins, granzyme mRNA, and perforin mRNA expression. The expression of CD11a, CD16, CD18, and CD56 were reduced, perforin mRNA levels were unchanged and granzyme mRNA levels were increased. To verify that activation of p44/42 was responsible for the alterations seen in CD11a, CD16, CD18, and CD56 with PMA, NK cells were treated with the p44/42 pathway inhibitor (PD98059) prior to PMA exposures. In the presence of PD98059, PMA caused no decreases in the expression of the cell-surface proteins. Results of these studies indicate that the activation of p44/42 may lead to the loss of NK cell cytotoxic function by decreasing the expression of CD11a, CD16, CD18, and CD56. Further, activation of p44/42 appears to be at least in part responsible for the TBT-induced decreases in expression of CD16, CD18, and CD56. PMID:20883105
Liver-resident NK cells and their potential functions.
Peng, Hui; Sun, Rui
2017-09-18
Natural killer (NK) cells represent a heterogeneous population of innate lymphocytes with phenotypically and functionally distinct subsets. In particular, recent studies have identified a unique subset of NK cells residing within the liver that are maintained as tissue-resident cells, confer antigen-specific memory responses and exhibit different phenotypical and developmental characteristics compared with conventional NK (cNK) cells. These findings have encouraged researchers to uncover tissue-resident NK cells at other sites, and detailed analyses have revealed that these tissue-resident NK cells share many similarities with liver-resident NK cells and tissue-resident memory T cells. Here, we present a brief historical perspective on the discovery of liver-resident NK cells and discuss their relationship to cNK cells and other emerging NK cell subsets and their potential functions.Cellular &Molecular Immunology advance online publication, 18 September 2017; doi:10.1038/cmi.2017.72.
Poznanski, Sophie M; Lee, Amanda J; Nham, Tina; Lusty, Evan; Larché, Margaret J; Lee, Dean A; Ashkar, Ali A
2017-01-01
The combination of interleukin (IL)-18 and IL-12 (IL-18+IL-12) potently stimulates natural killer (NK) cells, triggering an innate immune response to infections and cancers. Strategies exploiting the effects of IL-18+IL-12 have shown promise for cancer immunotherapy. However, studies have primarily characterized the NK cell response to IL-18+IL-12 in terms of interferon (IFN)-γ production, with little focus on other cytokines produced. IL-8 plays a critical role in activating and recruiting immune cells, but it also has tumor-promoting functions. IL-8 is classically produced by regulatory NK cells; however, cytotoxic NK cells do not typically produce IL-8. In this study, we uncover that stimulation with IL-18+IL-12 induces high levels of IL-8 production by ex vivo expanded and freshly isolated NK cells and NK cells in peripheral blood mononuclear cells. We further report that tumor necrosis factor (TNF)-α, produced by NK cells following IL-18+IL-12 stimulation, regulates IL-8 production. The IL-8 produced is in turn required for maximal IFN-γ and TNF-α production. These findings may have important implications for the immune response to infections and cancer immunotherapies. This study broadens our understanding of NK cell function and IL-18+IL-12 synergy by uncovering an unprecedented ability of IL-18+IL-12-activated peripheral blood NK cells to produce elevated levels of IL-8 and identifying the requirement for intermediates induced by IL-18+IL-12 for maximal cytokine production following stimulation. © 2017 S. Karger AG, Basel.
Meiotic recombination generates rich diversity in NK cell receptor genes, alleles, and haplotypes
Norman, Paul J.; Abi-Rached, Laurent; Gendzekhadze, Ketevan; Hammond, John A.; Moesta, Achim K.; Sharma, Deepti; Graef, Thorsten; McQueen, Karina L.; Guethlein, Lisbeth A.; Carrington, Christine V.F.; Chandanayingyong, Dasdayanee; Chang, Yih-Hsin; Crespí, Catalina; Saruhan-Direskeneli, Güher; Hameed, Kamran; Kamkamidze, Giorgi; Koram, Kwadwo A.; Layrisse, Zulay; Matamoros, Nuria; Milà, Joan; Park, Myoung Hee; Pitchappan, Ramasamy M.; Ramdath, D. Dan; Shiau, Ming-Yuh; Stephens, Henry A.F.; Struik, Siske; Tyan, Dolly; Verity, David H.; Vaughan, Robert W.; Davis, Ronald W.; Fraser, Patricia A.; Riley, Eleanor M.; Ronaghi, Mostafa; Parham, Peter
2009-01-01
Natural killer (NK) cells contribute to the essential functions of innate immunity and reproduction. Various genes encode NK cell receptors that recognize the major histocompatibility complex (MHC) Class I molecules expressed by other cells. For primate NK cells, the killer-cell immunoglobulin-like receptors (KIR) are a variable and rapidly evolving family of MHC Class I receptors. Studied here is KIR3DL1/S1, which encodes receptors for highly polymorphic human HLA-A and -B and comprises three ancient allelic lineages that have been preserved by balancing selection throughout human evolution. While the 3DS1 lineage of activating receptors has been conserved, the two 3DL1 lineages of inhibitory receptors were diversified through inter-lineage recombination with each other and with 3DS1. Prominent targets for recombination were D0-domain polymorphisms, which modulate enhancer function, and dimorphism at position 283 in the D2 domain, which influences inhibitory function. In African populations, unequal crossing over between the 3DL1 and 3DL2 genes produced a deleted KIR haplotype in which the telomeric “half” was reduced to a single fusion gene with functional properties distinct from its 3DL1 and 3DL2 parents. Conversely, in Eurasian populations, duplication of the KIR3DL1/S1 locus by unequal crossing over has enabled individuals to carry and express alleles of all three KIR3DL1/S1 lineages. These results demonstrate how meiotic recombination combines with an ancient, preserved diversity to create new KIR phenotypes upon which natural selection acts. A consequence of such recombination is to blur the distinction between alleles and loci in the rapidly evolving human KIR gene family. PMID:19411600
Exposure to diesel exhaust (DE) is known to exacerbate allergic inflammation, including virus induced eosinophil activation in laboratory animals. We have previously shown that in human volunteers with allergic rhinitis a short-term exposure to DE prior to infection with the live...
Wu, Feng-Hua; Mu, Lei; Li, Xiao-Lan; Hu, Yi-Bing; Liu, Hui; Han, Lin-Tao; Gong, Jian-Ping
2017-10-03
The concept of cancer stem cells has been proposed in various malignancies including colorectal cancer. Recent studies show direct evidence for quiescence slow-cycling cells playing a role in cancer stem cells. There exists an urgent need to isolate and better characterize these slow-cycling cells. In this study, we developed a new model to enrich slow-cycling tumor cells using cell-cycle inducer combined with cell cycle-dependent chemotherapy in vitro and in vivo . Our results show that Short-term exposure of colorectal cancer cells to chemotherapy combined with cell-cycle inducer enriches for a cell-cycle quiescent tumor cell population. Specifically, these slow-cycling tumor cells exhibit increased chemotherapy resistance in vitro and tumorigenicity in vivo . Notably, these cells are stem-cell like and participate in metastatic dormancy. Further exploration indicates that slow-cycling colorectal cancer cells in our model are less sensitive to cytokine-induced-killer cell mediated cytotoxic killing in vivo and in vitro . Collectively, our cell cycle inducer combined chemotherapy exposure model enriches for a slow-cycling, dormant, chemo-resistant tumor cell sub-population that are resistant to cytokine induced killer cell based immunotherapy. Studying unique signaling pathways in dormant tumor cells enriched by cell cycle inducer combined chemotherapy treatment is expected to identify novel therapeutic targets for preventing tumor recurrence.
Wu, Feng-Hua; Mu, Lei; Li, Xiao-Lan; Hu, Yi-Bing; Liu, Hui; Han, Lin-Tao; Gong, Jian-Ping
2017-01-01
The concept of cancer stem cells has been proposed in various malignancies including colorectal cancer. Recent studies show direct evidence for quiescence slow-cycling cells playing a role in cancer stem cells. There exists an urgent need to isolate and better characterize these slow-cycling cells. In this study, we developed a new model to enrich slow-cycling tumor cells using cell-cycle inducer combined with cell cycle-dependent chemotherapy in vitro and in vivo. Our results show that Short-term exposure of colorectal cancer cells to chemotherapy combined with cell-cycle inducer enriches for a cell-cycle quiescent tumor cell population. Specifically, these slow-cycling tumor cells exhibit increased chemotherapy resistance in vitro and tumorigenicity in vivo. Notably, these cells are stem-cell like and participate in metastatic dormancy. Further exploration indicates that slow-cycling colorectal cancer cells in our model are less sensitive to cytokine-induced-killer cell mediated cytotoxic killing in vivo and in vitro. Collectively, our cell cycle inducer combined chemotherapy exposure model enriches for a slow-cycling, dormant, chemo-resistant tumor cell sub-population that are resistant to cytokine induced killer cell based immunotherapy. Studying unique signaling pathways in dormant tumor cells enriched by cell cycle inducer combined chemotherapy treatment is expected to identify novel therapeutic targets for preventing tumor recurrence. PMID:29108242
Transcription Factor Foxo1 Is a Negative Regulator of NK Cell Maturation and Function
Deng, Youcai; Kerdiles, Yann; Chu, Jianhong; Yuan, Shunzong; Wang, Youwei; Chen, Xilin; Mao, Hsiaoyin; Zhang, Lingling; Zhang, Jianying; Hughes, Tiffany; Deng, Yafei; Zhang, Qi; Wang, Fangjie; Zou, Xianghong; Liu, Chang-Gong; Freud, Aharon G.; Li, Xiaohui; Caligiuri, Michael A; Vivier, Eric; Yu, Jianhua
2015-01-01
SUMMARY Little is known about the role of negative regulators in controlling natural killer (NK) cell development and effector functions. Foxo1 is a multifunctional transcription factor of the forkhead family. Using a mouse model of conditional deletion in NK cells, we found that Foxo1 negatively controlled NK cell differentiation and function. Immature NK cells expressed abundant Foxo1 and little Tbx21 relative to mature NK cells, but these two transcription factors reversed their expression as NK cells proceeded through development. Foxo1 promoted NK cell homing to lymph nodes through upregulating CD62L expression, and impaired late-stage maturation and effector functions by repressing Tbx21 expression. Loss of Foxo1 rescued the defect in late-stage NK cell maturation in heterozygous Tbx21+/− mice. Collectively, our data reveal a regulatory pathway by which the negative regulator Foxo1 and the positive regulator Tbx21 play opposing roles in controlling NK cell development and effector functions. PMID:25769609
In vitro atrazine-exposure inhibits human natural killer cell lytic granule release
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rowe, Alexander M.; Brundage, Kathleen M.; Center for Immunopathology and Microbial Pathogenesis, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, WV 26506
2007-06-01
The herbicide atrazine is a known immunotoxicant and an inhibitor of human natural killer (NK) cell lytic function. The precise changes in NK cell lytic function following atrazine exposure have not been fully elucidated. The current study identifies the point at which atrazine exerts its affect on the stepwise process of human NK cell-mediated lyses of the K562 target cell line. Using intracellular staining of human peripheral blood lymphocytes, it was determined that a 24-h in vitro exposure to atrazine did not decrease the level of NK cell lytic proteins granzyme A, granzyme B or perforin. Thus, it was hypothesizedmore » that atrazine exposure was inhibiting the ability of the NK cells to bind to the target cell and subsequently inhibit the release of lytic protein from the NK cell. To test this hypothesis, flow cytometry and fluorescent microscopy were employed to analyze NK cell-target cell co-cultures following atrazine exposure. These assays demonstrated no significant decrease in the level of target cell binding. However, the levels of NK intracellular lytic protein retained and the amount of lytic protein released were assessed following a 4-h incubation with K562 target cells. The relative level of intracellular lytic protein was 25-50% higher, and the amount of lytic protein released was 55-65% less in atrazine-treated cells than vehicle-treated cells following incubation with the target cells. These results indicate that ATR exposure inhibits the ability of NK cells to lyse target cells by blocking lytic granule release without affecting the ability of the NK cell to form stable conjugates with target cells.« less
Sjölin, Hanna; Tomasello, Elena; Mousavi-Jazi, Mehrdad; Bartolazzi, Armando; Kärre, Klas; Vivier, Eric; Cerboni, Cristina
2002-01-01
Natural killer (NK) cells are major contributors to early defense against infections. Their effector functions are controlled by a balance between activating and inhibiting signals. To date, however, the involvement of NK cell activating receptors and signaling pathways in the defense against pathogens has not been extensively investigated. In mice, several NK cell activating receptors are coexpressed with and function through the immunoreceptor tyrosine-based activation motif (ITAM)-bearing molecule KARAP/DAP12. Here, we have analyzed the role of KARAP/DAP12 in the early antiviral response to murine cytomegalovirus (MCMV). In KARAP/DAP12 mutant mice bearing a nonfunctional ITAM, we found a considerable increase in viral titers in the spleen (30–40-fold) and in the liver (2–5-fold). These effects were attributed to NK cells. The formation of hepatic inflammatory foci appeared similar in wild-type and mutant mice, but the latter more frequently developed severe hepatitis with large areas of focal necrosis. Moreover, the percentage of hepatic NK cells producing interferon γ was reduced by 56 ± 22% in the absence of a functional KARAP/DAP12. This is the first study that shows a crucial role for a particular activating signaling pathway, in this case the one induced through KARAP/DAP12, in the NK cell–mediated resistance to an infection. Our results are discussed in relation to recent reports demonstrating that innate resistance to MCMV requires the presence of NK cells expressing the KARAP/DAP12-associated receptor Ly49H. PMID:11927627
Oliveira, Sofia A.; Park, Se-Ho; Lee, Peter; Bendelac, Albert; Shenk, Thomas E.
2002-01-01
The murine cytomegalovirus m02 gene family encodes putative type I membrane glycoproteins named m02 through m16. A subset of these genes were fused to an epitope tag and cloned into an expression vector. In transfected and murine cytomegalovirus-infected cells, m02, m04, m05, m06, m07, m09, m10, and m12 localized to cytoplasmic structures near the nucleus, whereas m08 and m13 localized to a filamentous structure surrounding the nucleus. Substitution mutants lacking the m02 gene (SMsubm02) or the entire m02 gene family (SMsubm02-16) grew like their wild-type parent in cultured cells. However, whereas SMsubm02 was as pathogenic as the wild-type virus, SMsubm02-16 was markedly less virulent. SMsubm02-16 produced less infectious virus in most organs compared to wild-type virus in BALB/c and C57BL/6J mice, but it replicated to wild-type levels in the organs of immunodeficient γc/Rag2 mice, lacking multiple cell types including natural killer cells, and in C57BL/6J mice depleted of natural killer cells. These results argue that one or more members of the m02 gene family antagonize natural killer cell-mediated immune surveillance. PMID:11752177
Morimoto, K; Takeshita, T; Inoue-Sakurai, C; Maruyama, S
2001-04-10
We investigated the association of lifestyle and mental health status with natural killer (NK) cell and lymphokine-activated killer (LAK) cell activities in healthy males. NK cell activity was determined in 105 male workers and LAK cell activity was determined in 54 male workers. Peripheral blood was obtained from each subject and peripheral blood mononuclear cells (PBMC) were isolated from the blood. These PBMC were used as effector cells. LAK cells were generated by incubation of PBMC with interleukin-2 for 72 h. NK cell activity against NK-sensitive K562 cells and LAK cell activity against NK-resistant Raji cells were examined by 51Cr release assay. Overall lifestyles were evaluated according to the answers on a questionnaire regarding eight health practices (cigarette smoking, alcohol consumption, eating breakfast, hours of sleep, hours of work, physical exercise, nutritional balance, mental stress). Subjects with a good overall lifestyle showed significantly higher NK cell (P < 0.05) and LAK cell (P < 0.05) activities than those with a poor overall lifestyles. Among eight lifestyle factors, cigarette smoking has relatively strong effects on NK cell and LAK cell activities. Subjects who complained of unstable mental status had significantly lower NK cell activity than those who reported stable mental status. When subjects were divided into four groups by lifestyle and mental health status, subjects who had poor or moderate lifestyle and reported unstable mental status showed the lowest NK cell activity and subjects who had good lifestyle and reported stable mental status showed the highest NK cell activity among four groups.
Invariant natural killer T cells trigger adaptive lymphocytes to churn up bile.
Joyce, Sebastian; Van Kaer, Luc
2008-05-15
How innate immune response causes autoimmunity has remained an enigma. In this issue of Cell Host & Microbe, Mattner et al. demonstrate that invariant natural killer T cells activated by the mucosal commensal Novosphingobium aromaticivorans precipitate chronic T cell-mediated autoimmunity against small bile ducts that mirrors human primary biliary cirrhosis. These findings provide a mechanistic understanding of the role of innate immunity toward a microbe in the development of autoimmunity.
Recognition of unusual presentation of natural killer cell leukemia.
Gardiner, C M; Reen, D J; O'Meara, A
1995-10-01
Expansion of the natural killer (NK) subset of lymphocytes represents a rare leukemia phenotype with variations in clinical presentation, morphology, surface phenotype, and effector function. This paper reports on a 5-year-old male patient who had an unusual presentation of an NK cell leukemia that was initially diagnosed as neuroblastoma. A bone marrow (BM) aspirate showed clumps of undifferentiated cells with the following phenotype: CD56bright+, CD33dim+, CD45-, CD2-, CD19-, CD16-, and CD57-. Cytochemistry was noncontributory. The patient, having failed to respond to conventional neuroblastoma chemotherapy, was subsequently diagnosed as having NK cell leukemia based on functional in vitro assays. The patient responded to acute lymphoblastic leukemia (ALL) chemotherapy but relapsed 4 weeks into treatment and eventually died 25 weeks after initial presentation. The cell surface phenotype observed is consistent with a rare NK cell subset, the biology of which has not been well defined. Freshly isolated BM cells killed K562 cells in a conventional 51Cr-release assay. Both interleukin-2 (IL-2) and interferon-alpha (IFN-alpha) induced LAK activity against the Daudi cell line. IL-2 induced proliferation of the leukemic cells. TNF-alpha, IFN-gamma, IL-6, IL-1ra, and TGF-beta levels were assessed and found to be concentrated in BM, in contrast to plasma samples. TNF-alpha was present at a high concentration in BM (150.9 pg/ml), probably a reflection of the associated disease pathology of severe bone pain and pyrexia. In summary, this paper details clinical and laboratory investigations of a leukemia of a rare NK cell subset.
Invariant Natural Killer T Cells are Reduced in Hereditary Hemochromatosis Patients.
Maia, M L; Pereira, C S; Melo, G; Pinheiro, I; Exley, M A; Porto, G; Macedo, M F
2015-01-01
Invariant natural killer T (iNKT) cells are CD1d restricted-T cells that react to lipid antigens. iNKT cells were shown to be important in infection, autoimmunity and tumor surveillance. Alterations in the number and function of these cells were described in several pathological conditions including autoimmune and/or liver diseases. CD1d is critical for antigen presentation to iNKT cells, and its expression is increased in liver diseases. The liver is the major organ affected in Hereditary Hemochromatosis (HH), an autosomal recessive disorder caused by excessive iron absorption. Herein, we describe the study of iNKT cells of HH patients. Twenty-eight HH patients and 24 control subjects from Santo António Hospital, Porto, were included in this study. Patient's iron biochemical parameters (serum transferrin saturation and ferritin levels) and the liver function marker alanine transaminase (ALT) were determined at the time of study. Peripheral blood iNKT cells were analyzed by flow cytometry using an anti-CD3 antibody and the CD1d tetramer loaded with PBS57. We found a decrease in the percentage and number of circulating iNKT cells from HH patients when compared with control population independently of age. iNKT cell defects were more pronounced in untreated patients, relating with serum ferritin and transferrin saturation levels. No correlation was found with ALT, a marker of active liver dysfunction. Altogether, our results demonstrate that HH patients have reduced numbers of iNKT cells and that these are influenced by iron overload.
Andrew, Angeline S; Jewell, David A; Mason, Rebecca A; Whitfield, Michael L; Moore, Jason H; Karagas, Margaret R
2008-04-01
Arsenic exposure impairs development and can lead to cancer, cardiovascular disease, and diabetes. The mechanism underlying these effects remains unknown. Primarily because of geologic sources of contamination, drinking-water arsenic levels are above the current recommended maximum contaminant level of 10 microg/L in the northeastern, western, and north central regions of the United States. We investigated the effects of arsenic exposure, defined by internal biomarkers at levels relevant to the United States and similarly exposed populations, on gene expression. We conducted separate Affymetrix microarray-based genomewide analyses of expression patterns. Peripheral blood lymphocyte samples from 21 controls interviewed (1999-2002) as part of a case-control study in New Hampshire were selected based on high- versus low-level arsenic exposure levels. The biologic functions of the transcripts that showed statistically significant abundance differences between high- and low-arsenic exposure groups included an overrepresentation of genes involved in defense response, immune function, cell growth, apoptosis, regulation of cell cycle, T-cell receptor signaling pathway, and diabetes. Notably, the high-arsenic exposure group exhibited higher levels of several killer cell immunoglobulin-like receptors that inhibit natural killer cell activity. These findings define biologic changes that occur with chronic arsenic exposure in humans and provide leads and potential targets for understanding and monitoring the pathogenesis of arsenic-induced diseases.
Gao, Li-min; Liu, Wei-ping; Yang, Qun-pei; Li, Hui-fang; Chen, Jun-jie; Tang, Yuan; Zou, Yan; Liao, Dian-Ying; Liu, Yan-mei; Zhao, Sha
2013-03-11
Aggressive natural killer cell leukemia/lymphoma (ANKL) is a rare aggressive form of NK-cell neoplasm. We report an uncommon case of 36-year-old male who showed jaundice and spontaneous splenic rupture. The diagnosis was established by the biopsy of liver and spleen. The monomorphous medium-size neoplastic cells infiltrated into portal areas and sinus of liver as well as the cords and sinus of the spleen. Necrosis, mitotic figures and significant apoptosis could be seen easily. These neoplastic cells demonstrated a typical immunophenotype of CD3ε+, CD56+, CD16+, Granzyme B+, TIA-1+. T-cell receptor γ (TCR-γ) gene rearrangement analysis showed germline configuration and the result of in situ hybridization for Epstein-Barr virus-encoded RNA (EBER-ISH) was positive. The patient has undergone an aggressive clinical course and died of multi-organ function failure 14 days later after admission. To the best of our knowledge, this is the first case of ANKL with spontaneous splenic rupture, and we should pay more attention to recognize it. The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2048154883890867.
Huang, Yu; Chen, Zhiying; Jang, Joon Hee; Baig, Mirza S; Bertolet, Grant; Schroeder, Casey; Huang, Shengjian; Hu, Qian; Zhao, Yong; Lewis, Dorothy E; Qin, Lidong; Zhu, Michael Xi; Liu, Dongfang
2018-04-18
The inhibitory receptor programmed cell death protein 1 (PD-1) is upregulated on a variety of immune cells, including natural killer (NK) cells, during chronic viral infection and tumorigenesis. Blockade of PD-1 or its ligands produces durable clinical responses with tolerable side effects in patients with a broad spectrum of cancers. However, the underlying molecular mechanisms of how PD-1 regulates NK cell function remain poorly characterized. We sought to determine the effect of PD-1 signaling on NK cells. PD-1 was overexpressed in CD16-KHYG-1 (a human NK cell line with both antibody-dependent cellular cytotoxicity through CD16 and natural cytotoxicity through NKG2D) cells and stimulated by exposing the cells to NK-sensitive target cells expressing programmed death ligand 1 (PD-L1). PD-1 engagement by PD-L1 specifically blocked NK cell-mediated cytotoxicity without interfering with the conjugation between NK cells and target cells. Further examination showed that PD-1 signaling blocked lytic granule polarization in NK cells, which was accompanied by failure of integrin-linked kinase, a key molecule in the integrin outside-in signaling pathway, to accumulate in the immunological synapse after NK-target cell conjugation. Our results suggest that NK cell cytotoxicity is inhibited by PD-1 engagement, which blocks lytic granule polarization to the NK cell immunological synapse with concomitant impairment of integrin outside-in signaling. This study provides novel mechanistic insights into how PD-1 inhibition disrupts NK cell function. Copyright © 2018 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.
Buer, J; Hilse, R; Dallmann, I; Grosse, J; Kirchner, H; Zorn, U; Hänninen, E L; Franzke, A; Duensing, S; Poliwoda, H
1995-03-01
In this study, effective antitumour immunity was transferred by autologous short activated killer (SHAK) cells induced over four hours with lymphocyte conditioned medium (LCM) and recombinant interleukin-2 (rIL-2). Among eight patients with progressive metastatic renal cell carcinoma refractory to standard therapy, there were six objective tumour responses to SHAKs. Progression-free survival ranged from 0 to 8+ months, and overall survival ranged from 2 to 14+ months, with a median of 9+ months. Systemic toxicity of SHAKs was limited to flulike symptoms. Patient SHAKs provided a tumour-specific immunity, both cellular and humoral (expression and secretion of secondary cytokines, including IL-2, GM-CSF, INF-gamma and TNF-alpha), far superior to rIL-2 activated killer cells.
GATA-3 function in innate and adaptive immunity.
Tindemans, Irma; Serafini, Nicolas; Di Santo, James P; Hendriks, Rudi W
2014-08-21
The zinc-finger transcription factor GATA-3 has received much attention as a master regulator of T helper 2 (Th2) cell differentiation, during which it controls interleukin-4 (IL-4), IL-5, and IL-13 expression. More recently, GATA-3 was shown to contribute to type 2 immunity through regulation of group 2 innate lymphoid cell (ILC2) development and function. Furthermore, during thymopoiesis, GATA-3 represses B cell potential in early T cell precursors, activates TCR signaling in pre-T cells, and promotes the CD4(+) T cell lineage after positive selection. GATA-3 also functions outside the thymus in hematopoietic stem cells, regulatory T cells, CD8(+) T cells, thymic natural killer cells, and ILC precursors. Here we discuss the varied functions of GATA-3 in innate and adaptive immune cells, with emphasis on its activity in T cells and ILCs, and examine the mechanistic basis for the dose-dependent, developmental-stage- and cell-lineage-specific activity of this transcription factor. Copyright © 2014 Elsevier Inc. All rights reserved.
Bonamichi, Beatriz Dal Santo Francisco; Lee, Jongsoon
2017-08-01
The notion that obesity-induced inflammation mediates the development of insulin resistance in animal models and humans has been gaining strong support. It has also been shown that immune cells in local tissues, in particular in visceral adipose tissue, play a major role in the regulation of obesity-induced inflammation. Specifically, obesity increases the numbers and activation of proinflammatory immune cells, including M1 macrophages, neutrophils, Th1 CD4 T cells, and CD8 T cells, while simultaneously suppressing anti-inflammatory cells such as M2 macrophages, CD4 regulatory T cells, regulatory B cells, and eosinophils. Recently, however, new cell types have been shown to participate in the development of obesity-induced inflammation and insulin resistance. Some of these cell types also appear to regulate obesity. These cells are natural killer (NK) cells and innate lymphoid cells (ILCs), which are closely related, and invariant natural killer T (iNKT) cells. It should be noted that, although iNKT cells resemble NK cells in name, they are actually a completely different cell type in terms of their development and functions in immunity and metabolism. In this review, we will focus on the roles that these relatively new players in the metabolism field play in obesity-induced insulin resistance and the regulation of obesity. Copyright © 2017 Korean Diabetes Association.
Marquardt, Nicole; Ivarsson, Martin A; Blom, Kim; Gonzalez, Veronica D; Braun, Monika; Falconer, Karolin; Gustafsson, Rasmus; Fogdell-Hahn, Anna; Sandberg, Johan K; Michaëlsson, Jakob
2015-10-01
NK cells play an important role in the defense against viral infections. However, little is known about the regulation of NK cell responses during the first days of acute viral infections in humans. In this study, we used the live attenuated yellow fever virus (YFV) vaccine 17D as a human in vivo model to study the temporal dynamics and regulation of NK cell responses in an acute viral infection. YFV induced a robust NK cell response in vivo, with an early activation and peak in NK cell function at day 6, followed by a delayed peak in Ki67 expression, which was indicative of proliferation, at day 10. The in vivo NK cell response correlated positively with plasma type I/III IFN levels at day 6, as well as with the viral load. YFV induced an increased functional responsiveness to IL-12 and IL-18, as well as to K562 cells, indicating that the NK cells were primed in vivo. The NK cell responses were associated primarily with the stage of differentiation, because the magnitude of induced Ki67 and CD69 expression was distinctly higher in CD57(-) NK cells. In contrast, NK cells expressing self- and nonself-HLA class I-binding inhibitory killer cell Ig-like receptors contributed, to a similar degree, to the response. Taken together, our results indicate that NK cells are primed by type I/III IFN in vivo early after YFV infection and that their response is governed primarily by the differentiation stage, independently of killer cell Ig-like receptor/HLA class I-mediated inhibition or education. Copyright © 2015 by The American Association of Immunologists, Inc.
NASA Technical Reports Server (NTRS)
Chapes, S. K.; Hoynowski, S. M.; Woods, K. M.; Armstrong, J. W.; Beharka, A. A.; Iandolo, J. J.; Spooner, B. S. (Principal Investigator)
1993-01-01
We used major histocompatibility complex class II antigen-deficient transgenic mice to show that in vitro natural killer cell cytotoxicity and T-cell activation by staphylococcal exotoxins (superantigens) are not dependent upon the presence of major histocompatibility complex class II molecules. T cells can be activated by exotoxins in the presence of exogenously added interleukin 1 or 2 or in the presence of specific antibody without exogenously added cytokines.
Purdy, Amanda K.; Alvarez-Arias, Diana A.; Oshinsky, Jennifer; James, Ashley M.; Serebriiskii, Ilya; Campbell, Kerry S.
2014-01-01
Stable surface expression of human inhibitory killer cell immunoglobulin-like receptors (KIR) is critical for controlling NK cell function and maintaining NK cell tolerance toward normal MHC-I+ cells. Our recent experiments, however, have found that antibody-bound KIR3DL1 (3DL1) readily leaves the cell surface and undergoes endocytosis to early/recycling endosomes and subsequently to late endosomes. We found that 3DL1 internalization is at least partially mediated by an interaction between the μ2 subunit of the AP-2 clathrin adaptor complex and ITIM tyrosine residues in the cytoplasmic domain of 3DL1. Disruption of the 3DL1/μ2 interaction, either by mutation of the ITIM tyrosines in 3DL1 or mutation of μ2, significantly diminished endocytosis and increased surface expression of 3DL1 in human primary NK cells and cell lines. Furthermore, we found that the 3DL1/AP-2 interaction is diminished upon antibody engagement with the receptor, as compared to untreated cells. Thus, we have identified AP-2-mediated endocytosis as a mechanism regulating the surface levels of inhibitory KIR though their ITIM domains. Based upon our results, we propose a model in which non-engaged KIR are internalized by this mechanism, whereas engagement with MHC-I ligand would diminish AP-2 binding, thereby prolonging stable receptor surface expression and promoting inhibitory function. Furthermore, this ITIM-mediated mechanism may similarly regulate the surface expression of other inhibitory immune receptors. PMID:25238755
Huang, X L; Fan, Z; Murayama, T; Rinaldo, C
1995-01-01
A decrease in natural killer (NK) cell function has been related to the progression of human immunodeficiency virus (HIV) infection. In the present study, we assessed the ability of a streptococcus-derived biologic response modifier, OK-432, to augment NK lysis of uninfected K562 and U937 cells and HIV-infected U937 cells by peripheral blood mononuclear cells (PBMC) from HIV-seropositive homosexual men. Optimal two- to fourfold increases in lysis of the three targets were observed after pretreatment of PBMC from HIV-negative subjects for 4 h with 2 micrograms of OK-432 per ml. This effect was related primarily to gamma interferon (IFN-gamma) production induced by OK-432 and was not linked to production of tumor necrosis factors alpha and beta or to monocytes in the cultures. The enhancing effect of OK-432 on NK cell function was diminished but still evident in PBMC from subjects with relatively early-phase (< 3-year) HIV infection and high CD4+ cell counts and was lower in subjects with longer-term HIV infection (> 3 years), in association with reduced production of IFN-gamma. Augmentation of NK cell activity in HIV-infected men by OK-432 was comparable to that induced by treatment of cells with 1,000 U of IFN-alpha or interleukin 2 per ml. The data suggest that the NK cell-enhancing effects of OK-432 are at least in part mediated by IFN-gamma and that OK-432 may be effective in treatment of patients with early-phase HIV infection. PMID:7719919
Chalan, Paulina; Bijzet, Johan; Kroesen, Bart-Jan; Boots, Annemieke M H; Brouwer, Elisabeth
2016-06-01
The role of natural killer (NK) cells in the immunopathogenesis of rheumatoid arthritis (RA) is unclear. Therefore, numerical and functional alterations of CD56(dim) and CD56(bright) NK cells in the early stages of RA development were studied. Whole blood samples from newly diagnosed, treatment-naive, seropositive (SP) and seronegative (SN) patients with RA (SP RA, n = 45 and SN RA, n = 12), patients with SP arthralgia (n = 30), and healthy controls (HC, n = 41) were assessed for numbers and frequencies of T cells, B cells, and NK cells. SP status was defined as positive for anticyclic citrullinated peptide antibodies (anti-CCP) and/or rheumatoid factor (RF). Peripheral blood mononuclear cells were used for further analysis of NK cell phenotype and function. Total NK cell numbers were decreased in SP RA and SP arthralgia but not in SN RA. Also, NK cells from SP RA showed a decreased potency for interferon-γ (IFN-γ) production. A selective decrease of CD56(dim), but not CD56(bright), NK cells in SP RA and SP arthralgia was observed. This prompted investigation of CD16 (FcγRIIIa) triggering in NK cell apoptosis and cytokine expression. In vitro, CD16 triggering induced apoptosis of CD56(dim) but not CD56(bright) NK cells from HC. This apoptosis was augmented by adding interleukin 2 (IL-2). Also, CD16 triggering in the presence of IL-2 stimulated IFN-γ and tumor necrosis factor-α expression by CD56(dim) NK cells. The decline of CD56(dim) NK cells in SP arthralgia and SP RA and the in vitro apoptosis of CD56(dim) NK cells upon CD16 triggering suggest a functional role of immunoglobulin G-containing autoantibody (anti-CCP and/or RF)-immune complexes in this process. Moreover, CD16-triggered cytokine production by CD56(dim) NK cells may contribute to systemic inflammation as seen in SP arthralgia and SP RA.
Dudimah, Fred D; Odman-Ghazi, Sabah O; Hatcher, Frank; Whalen, Margaret M
2007-01-01
The purpose of this study was to investigate the role that tributyltin (TBT)-induced decreases in ATP levels may play in TBT-induced decreases in the tumor lysing (lytic) function of natural killer (NK) cells. NK cells are a subset of lymphocytes that act as an initial immune defense against tumor cells and virally infected cells. TBT is an environmental contaminant that has been detected in human blood, which has been shown to interfere with ATP synthesis. Previous studies have shown that TBT is able to decrease very significantly the lytic function of NK cells. In this study NK cells were exposed to various concentrations of TBT and to two other compounds that interfere with ATP synthesis (rotenone a complex I inhibitor and oligomycin an ATP synthase inhibitor) for various lengths of time before determining the levels of ATP and lytic function. Exposures of NK cells to 10, 25, 50 and 100 nm TBT did not significantly reduce ATP levels after 24 h. However, these same exposures caused significant decreases in cytotoxic function. Studies of brief 1 h exposures to a range of TBT, rotenone and oligomycin concentrations followed by 24 h, 48 h and 6 day periods in compound-free media prior to assaying for ATP levels or cytotoxic function showed that each of the compounds caused persistent decreases in ATP levels and lytic function of NK cells. Exposures to 0.05-5 microm rotenone or oligomycin for 1 h reduced ATP levels by 20-25% but did not have any measurable effect on the ability of NK cells to lyse tumor cells. ATP levels were also decreased by about 20-25% after 24 h or 48 h exposures to rotenone or oligomycin (0.5 microm ), and the lytic function was decreased by about 50%. The results suggest that TBT-induced decreases in ATP levels were not responsible for the loss of cytotoxic function seen at 1 h and 24 h. However, TBT-induced decreases of NK-ATP levels may be at least in part responsible for losses of NK-cytotoxic function seen after 48 h and 6 day exposures. Copyright 2006 John Wiley & Sons, Ltd.
Hershkovitz, Oren; Rosental, Benyamin; Rosenberg, Lior Ann; Navarro-Sanchez, Martha Erika; Jivov, Sergey; Zilka, Alon; Gershoni-Yahalom, Orly; Brient-Litzler, Elodie; Bedouelle, Hugues; Ho, Joanna W.; Campbell, Kerry S.; Rager-Zisman, Bracha; Despres, Philippe; Porgador, Angel
2009-01-01
Dengue virus (DV) and West Nile virus (WNV) have become a global concern due to their widespread distribution and their ability to cause a variety of human diseases. Antiviral immune defenses involve natural killer (NK) cells. In the present study, we investigated the interaction between NK cells and these two flaviviruses. We show that the NK-activating receptor NKp44 is involved in virally-mediated NK activation through direct interaction with the flavivirus envelope protein. Recombinant NKp44 directly binds to purified DV and WNV envelope proteins and specifically to domain III of WNV envelope protein (EIII); it also binds to WNV virus-like particles (VLPs). These WNV-VLPs and WNV-EIII directly bind NK cells expressing high levels of NKp44. Functionally, interaction of NK cells with infective and inactivated WNV results in NKp44-mediated NK de-granulation. Finally, WNV infection of cells results in increased binding of recombinant NKp44 that is specifically inhibited by anti-WNV serum. WNV-infected target cells induce IFNγ secretion and augmented lysis by NKp44-expressing primary NK cells that are blocked by anti-NKp44 antibodies. Our findings show that triggering of NK cells by flavivirus is mediated by interaction of NKp44 with the flavivirus envelope protein. PMID:19635919
Hodge, D.L.; Subleski, J.J.; Reynolds, D.A.; Buschman, M.D.; Schill, W.B.; Burkett, M.W.; Malyguine, A.M.; Young, H.A.
2006-01-01
The proinflammatory cytokine, interleukin-18 (IL-18), is a natural killer (NK) cell activator that induces NK cell cytotoxicity and interferon-?? (IFN-??) expression. In this report, we define a novel role for IL-18 as an NK cell protective agent. Specifically, IL-18 prevents NK cell death initiated by different and distinct stress mechanisms. IL-18 reduces NK cell self-destruction during NK-targeted cell killing, and in the presence of staurosporin, a potent apoptotic inducer, IL-18 reduces caspase-3 activity. The critical regulatory step in this process is downstream of the mitochondrion and involves reduced cleavage and activation of caspase-9 and caspase-3. The ability of IL-18 to regulate cell survival is not limited to a caspase death pathway in that IL-18 augments tumor necrosis factor (TNF) signaling, resulting in increased and prolonged mRNA expression of c-apoptosis inhibitor 2 (cIAP2), a prosurvival factor and caspase-3 inhibitor, and TNF receptor-associated factor 1 (TRAF1), a prosurvival protein. The cumulative effects of IL-18 define a novel role for this cytokine as a molecular survival switch that functions to both decrease cell death through inhibition of the mitochondrial apoptotic pathway and enhance TNF induction of prosurvival factors. ?? Mary Ann Liebert, Inc.
Maghazachi, Azzam A
2005-09-01
Human natural killer (NK) cells are important cells of the innate immune system. These cells perform two prominent functions: the first is recognizing and destroying virally infected cells and transformed cells; the second is secreting various cytokines that shape up the innate and adaptive immune re-sponses. For these cells to perform these activities, they express different sets of receptors. The receptors used by NK cells to extravasate into sites of injury belong to the seven transmembrane (7TM) family of receptors, which characteristically bind heterotrimeric G proteins. These receptors allow NK cells to sense the chemotactic gradients and activate second messengers, which aid NK cells in polarizing and migrating toward the sites of injured tissues. In addition, these receptors determine how and why human resting NK cells are mainly found in the bloodstream, whereas activated NK cells extravasate into inflammatory sites. Receptors for chemokines and lysophospholipids belong to the 7TM family. On the other hand, NK cells recognize invading or transformed cells through another set of receptors that belong to the single transmembrane-spanning domain family. These receptors are either inhibitory or activating. Inhibitory receptors contain the immune receptor tyrosine-based inhibitory motif, and activating receptors belong to either those that associate with adaptor molecules containing the immune receptor tyrosine-based activating motif (ITAM) or those that associate with adaptor molecules containing motifs other than ITAM. This article will describe the nature of these receptors and examine the intracellular signaling pathways induced in NK cells after ligating both types of receptors. These pathways are crucial for NK cell biology, development, and functions.
Spiegel, Asaf; Brooks, Mary W.; Houshyar, Samin; Reinhardt, Ferenc; Ardolino, Michele; Fessler, Evelyn; Chen, Michelle B.; Krall, Jordan A.; DeCock, Jasmine; Zervantonakis, Ioannis K.; Iannello, Alexandre; Iwamoto, Yoshiko; Cortez-Retamozo, Virna; Kamm, Roger D.; Pittet, Mikael J.; Raulet, David H.; Weinberg, Robert A.
2016-01-01
Immune cells promote the initial metastatic dissemination of carcinoma cells from primary tumors. In contrast to their well-studied functions in the initial stages of metastasis, the specific roles of immunocytes in facilitating progression through the critical later steps of the invasion-metastasis cascade remain poorly understood. Here we define novel functions of neutrophils in promoting intraluminal survival and extravasation at sites of metastatic dissemination. We show that CD11b+/Ly6G+ neutrophils enhance metastasis formation via two distinct mechanisms. First, neutrophils inhibit natural killer cell function, which leads to a significant increase in the intraluminal survival time of tumor cells. Thereafter, neutrophils operate to facilitate extravasation of tumor cells through the secretion of IL-1β and matrix metalloproteinases. These results identify neutrophils as key regulators of intraluminal survival and extravasation through their crosstalk with host cells and disseminating carcinoma cells. PMID:27072748
Evaluation of immune functions in captive immature loggerhead sea turtles (Caretta caretta).
Rousselet, Estelle; Levin, Milton; Gebhard, Erika; Higgins, Benjamin M; DeGuise, Sylvain; Godard-Codding, Céline A J
2013-11-15
Sea turtles face numerous environmental challenges, such as exposure to chemical pollution and biotoxins, which may contribute to immune system impairment, resulting in increased disease susceptibility. Therefore, a more thorough assessment of the host's immune response and its susceptibility is needed for these threatened and endangered animals. In this study, the innate and acquired immune functions of sixty-five clinically healthy, immature, captive loggerhead sea turtles (Caretta caretta) were assayed using non-lethal blood sample collection. Functional immune assays were developed and/or optimized for this species, including mitogen-induced lymphocyte proliferation, natural killer (NK) cell activity, phagocytosis, and respiratory burst. Peripheral blood mononuclear cells (PBMC) and phagocytes were isolated by density gradient centrifugation on Ficoll-Paque and discontinuous Percoll gradients, respectively. The T lymphocyte mitogens ConA significantly induced lymphocyte proliferation at 1 and 2 μg/mL while PHA significantly induced lymphocyte proliferation at 5 and 10 μg/mL. The B lymphocyte mitogen LPS significantly induced proliferation at 1 μg/mL. Monocytes demonstrated higher phagocytic activity than eosinophils. In addition, monocytes exhibited respiratory burst. Natural killer cell activity was higher against YAC-1 than K-562 target cells. These optimized assays may help to evaluate the integrity of loggerhead sea turtle's immune system upon exposure to environmental contaminants, as well as part of a comprehensive health assessment and monitoring program. Copyright © 2013 Elsevier B.V. All rights reserved.
Innate lymphoid cells and natural killer T cells in the gastrointestinal tract immune system.
Montalvillo, Enrique; Garrote, José Antonio; Bernardo, David; Arranz, Eduardo
2014-05-01
The gastrointestinal tract is equipped with a highly specialized intrinsic immune system. However, the intestine is exposed to a high antigenic burden that requires a fast, nonspecific response -so-called innate immunity- to maintain homeostasis and protect the body from incoming pathogens. In the last decade multiple studies helped to unravel the particular developmental requirements and specific functions of the cells that play a role in innate immunity. In this review we shall focus on innate lymphoid cells, a newly discovered, heterogeneous set of cells that derive from an Id2-dependent lymphoid progenitor cell population. These cells have been categorized on the basis of the pattern of cytokines that they secrete, and the transcription factors that regulate their development and functions. Innate lymphoid cells play a role in the early response to pathogens, the anatomical contention of the commensal flora, and the maintenance of epithelial integrity.Amongst the various innate lymphoid cells we shall lay emphasis on a subpopulation with several peculiarities, namely that of natural killer T cells, a subset of T lymphocytes that express both T-cell and NK-cell receptors. The most numerous fraction of the NKT population are the so-called invariant NKT or iNKT cells. These iNKT cells have an invariant TCR and recognize the glycolipidic structures presented by the CD1d molecule, a homolog of class-I MHC molecules. Following activation they rapidly acquire cytotoxic activity and secrete both Th1 and Th2 cytokines, including IL-17. While their specific role is not yet established, iNKT cells take part in a great variety of intestinal immune responses ranging from oral tolerance to involvement in a number of gastrointestinal conditions.
Micro-encapsulated sensors for in vivo assessment of the oxidative stress in aquatic organisms
NASA Astrophysics Data System (ADS)
Sadovoy, Anton; Teh, Cathleen; Escobar, Marco; Meglinski, Igor; Korzh, Vladimir
2011-10-01
Oxidative stress results from an imbalance between the production and detoxification of reactive oxygen spices (ROS). ROS are natural byproducts of normal metabolism of oxygen and have important roles in cell signaling and homeostasis. Many heart related diseases like heart failure and myocardial infarction develop as a result of oxidative stress. Current treatment cannot improve the progressive decline in heart function experienced by all patients. Therefore heart failure is the cause of around 25% of all deaths in the Asia Pacific region. Thus any step taken to address the oxidative stress problem is essential for enhancing human health and improve their quality of life. Current approach is dedicated to develop micron-size oxidation stress-sensor for in-vivo measuring level of ROS in KillerRed expressing transgenic zebrafish larvae. Central to our investigation is the light-inducible heart failure animal model we developed in zebrafish that expressed KillerRed in the heart. By utilizing the photosensitizer properties of KillerRed to produce ROS upon green light illumination, heart failure can be repeatedly induced in a non-invasive manner. Importantly, the use of this biological platform permits the development of physiologically sensitive ROS sensor and identifies efficient antioxidants that improve heart contractility. The biosensor approach is based on utilizing biocompatible polyelectrolyte microcapsules as a carry of fluorescent dyes sensitive to amount of reactive oxygen spices. Microcapsule prevents dye diffusion in tissue that makes use toxic dyes possible. Microcapsule's wall is permeable for environment with size less than 500 Da. The oxidation stress-sensors are injected directly in zebrafish pericardium with further circulation along blood system. Detecting of ROS is obtained by using laser scanning microscopy by illuminating oxidation stress-sensors and detecting changing excitation signal from the fluorescent dye.
Micro-encapsulated sensors for in vivo assessment of the oxidative stress in aquatic organisms
NASA Astrophysics Data System (ADS)
Sadovoy, Anton; Teh, Cathleen; Escobar, Marco; Meglinski, Igor; Korzh, Vladimir
2012-03-01
Oxidative stress results from an imbalance between the production and detoxification of reactive oxygen spices (ROS). ROS are natural byproducts of normal metabolism of oxygen and have important roles in cell signaling and homeostasis. Many heart related diseases like heart failure and myocardial infarction develop as a result of oxidative stress. Current treatment cannot improve the progressive decline in heart function experienced by all patients. Therefore heart failure is the cause of around 25% of all deaths in the Asia Pacific region. Thus any step taken to address the oxidative stress problem is essential for enhancing human health and improve their quality of life. Current approach is dedicated to develop micron-size oxidation stress-sensor for in-vivo measuring level of ROS in KillerRed expressing transgenic zebrafish larvae. Central to our investigation is the light-inducible heart failure animal model we developed in zebrafish that expressed KillerRed in the heart. By utilizing the photosensitizer properties of KillerRed to produce ROS upon green light illumination, heart failure can be repeatedly induced in a non-invasive manner. Importantly, the use of this biological platform permits the development of physiologically sensitive ROS sensor and identifies efficient antioxidants that improve heart contractility. The biosensor approach is based on utilizing biocompatible polyelectrolyte microcapsules as a carry of fluorescent dyes sensitive to amount of reactive oxygen spices. Microcapsule prevents dye diffusion in tissue that makes use toxic dyes possible. Microcapsule's wall is permeable for environment with size less than 500 Da. The oxidation stress-sensors are injected directly in zebrafish pericardium with further circulation along blood system. Detecting of ROS is obtained by using laser scanning microscopy by illuminating oxidation stress-sensors and detecting changing excitation signal from the fluorescent dye.
Thio-isoglobotrihexosylceramide, an agonist for activating invariant natural killer T cells.
Xia, Chengfeng; Zhou, Dapeng; Liu, Chengwen; Lou, Yanyan; Yao, Qingjia; Zhang, Wenpeng; Wang, Peng George
2006-11-23
Thio-isoglobotrihexosylceramide (S-iGb3) might be resistant to alpha-galactosidases in antigen-presenting cells and have a longer retaining time in the lysosome before being loaded to CD1d. The biological assay showed that S-iGb3 demonstrates a much higher increase as a stimulatory ligand toward invariant natural killer T (iNKT) cells as compared to iGb3. [structure: see text].
Nguyen, S; Beziat, V; Dhedin, N; Kuentz, M; Vernant, J P; Debre, P; Vieillard, V
2009-05-01
Natural killer (NK) cells generated after haploidentical hematopoietic SCT in patients with AML are characterized by specific phenotypic features and impaired functioning that may affect transplantation outcome. We show that IFN-gamma produced by immature CD56(bright) NK cells upregulates cell surface expression of HLA-E on AML blasts and that this upregulation protects leukemic cells from NK-mediated cell lysis through the mediation of CD94/NKG2A, an inhibitory receptor overexpressed on NK cells after haploidentical SCT. Two years after transplantation, however, maturing NK cells were functionally active, as evidenced by high cytotoxicity and poor IFN-gamma production. This implies that maturation of NK cells is the key to improved immune responses and transplantation outcome.
Lamas, Bruno; Nachat-Kappes, Rachida; Goncalves-Mendes, Nicolas; Mishellany, Florence; Rossary, Adrien; Vasson, Marie-Paule; Farges, Marie-Chantal
2015-01-01
High-calorie (HC) diet contributes to the increased incidence of obesity, which is a risk factor for breast cancer in postmenopausal women, and in particular for estrogen receptor (ER) positive tumors. This study investigated whether an HC diet increases human ER-positive breast cancer progression and modulates natural killer (NK) cell functions. Four-week-old female BALB/c athymic nude mice were fed a HC diet (5320 kcal/kg) or standard calorie diet (SC, 2820 kcal/kg) for 6 mo. After 5 mo, the mice were randomly implanted with MCF-7 breast cancer cells (SCT and HCT) or received an isovolumic injection (SC and HC) in both inguinal fat pads. Tumor growth was greater in the HCT group than in the SC group without change in body weight. The HC diet decreased the tumor expression of genes involved in the citrate cycle and in adiponectin and lipid metabolism but increased that of genes controlling glycolysis and angiogenesis. The tumor expression level of Ki67 was increased while that of the cleaved caspase 3 and the ER-β and progesterone receptors was reduced. Tumor development in response to the HC diet was associated with smaller numbers and lower cytotoxicity of splenic NK cells. These results indicate that an HC diet without body weight gain increases ER-positive breast cancer cell proliferation and reduces tumor apoptosis. The underlying mechanisms might involve a downexpression of tumor hormonal receptor and reduced NK cell functions, and might also result in the regulation of genes involved in several cellular functions. © 2013 Wiley Periodicals, Inc.
Wang, Liming; Huang, Shigao; Dang, Yazheng; Li, Ming; Bai, Wen; Zhong, Zhanqiang; Zhao, Hongliang; Li, Yang; Liu, Yongjun; Wu, Mingyuan
2014-12-01
Esophageal cancer is a serious malignancy with regards to mortality and prognosis. Current treatment options include multimodality therapy mainstays of current treatment including surgery, radiation, and chemotherapy. Cell therapy for esophageal cancer is an advancing area of research. We report a case of esophageal cancer following cord blood-derived cytokine-induced killer cell infusion and adjuvant radiotherapy. Initially, she presented with poor spirit, full liquid diets, and upper abdominal pain. Through cell therapy plus adjuvant radiotherapy, the patient remitted and was self-reliant. Recognition of this curative effect of sequent therapy for esophageal cancer is important to enable appropriate treatment. This case highlights cord blood-derived cytokine-induced killer cell therapy significantly alleviates the adverse reaction of radiation and improves the curative effect. Cell therapy plus adjuvant radiotherapy can be a safe and effective treatment for esophageal cancer.
Blastic natural killer cell leukaemia in a dog--a case report.
Bonkobara, Makoto; Saito, Taro; Yamashita, Masahiro; Tamura, Kyoichi; Yagihara, Hiroko; Isotani, Mayu; Sato, Takashi; Washizu, Tsukimi
2007-11-01
A case of canine non-T, non-B lymphoid leukaemia was determined to be of natural killer (NK) cell lineage by detecting specific expression of canine CD56 mRNA by reverse transcriptase polymerase chain reaction analysis. Although NK cells are usually considered to be morphologically large granular lymphocytes, the malignant NK cells in this case were agranular and blast-like, resembling human blastic NK cell leukaemia. The prognosis of human NK cell leukaemia is usually poor. In this case, the dog died 10 days after initial presentation, despite chemotherapy.
Interaction between dendritic cells and natural killer cells during pregnancy in mice.
Blois, Sandra M; Barrientos, Gabriela; Garcia, Mariana G; Orsal, Arif S; Tometten, Mareike; Cordo-Russo, Rosalia I; Klapp, Burghard F; Santoni, Angela; Fernández, Nelson; Terness, Peter; Arck, Petra C
2008-07-01
A complex regulation of innate and adaptive immune responses at the maternal fetal interface promotes tolerance of trophoblast cells carrying paternally derived antigens. Such regulatory functions involve uterine dendritic cells (uDC) and natural killer (uNK) cells. The existence of a NK and DC "cross talk" has been revealed in various experimental settings; its biological significance ranging from cooperative stimulation to cell lysis. Little is known about the presence or role of NK and DC cross talk at the maternal fetal interface. The present study shows that mouse NK and DC interactions are subject to modulation by trophoblast cells in vitro. This interaction promotes a tolerogenic microenvironment characterized by downregulation of the expression of activation markers on uNK cells and uDC and dominance of Th2 cytokines. NK and DC interactions would also influence uterine cell proliferation and this process would be strongly modulated by trophoblast-derived signals. Indeed; while low proliferation rates were observed upon regular coculture allowing direct contact between uterine cells and trophoblasts, incubation in a transwell culture system markedly increased uterine cell proliferation suggesting that soluble factors are key mediators in the molecular "dialog" between the mother and the conceptus during the establishment of mouse pregnancy. Our data further reveal that the regulatory functions of trophoblast cells associated with tolerance induction are impaired in high abortion murine matings. Interestingly, we observed that secretion of interleukin-12p70 by uDC is dramatically abrogated in the presence of uNK cells. Taken together, our results provide the first evidence that a delicate balance of interactions involving NK cells, DC, and trophoblasts at the mouse maternal fetal interface supports a successful pregnancy outcome.
Pyridostigmine bromide (PYR) alters immune function in B6C3F1 mice.
Peden-Adams, M M; Dudley, A C; EuDaly, J G; Allen, C T; Gilkeson, G S; Keil, D E
2004-02-01
Pyridostigmine bromide (PYR) is an anticholinesterase drug indicated for the treatment of myasthenia gravis and neuromuscular blockade reversal. It acts as a reversible cholinesterase inhibitor and was used as a pretreatment for soldiers during Operation Desert Storm to protect against possible nerve gas attacks. Since that time, PYR has been implicated as a possible causative agent contributing to Gulf War Illness. PYR's mechanism of action has been well-delineated with regards to its effects on the nervous system, yet little is known regarding potential effects on immunological function. To evaluate the effects of PYR on immunological function, adult female B6C3F1 mice were gavaged daily for 14 days with PYR (0, 1, 5, 10, or 20 mg/kg/day). Immune parameters assessed were lymphoproliferation, natural killer cell activity, the SRBC-specific antibody plaque-forming cell (PFC) response, thymus and spleen weight and cellularity, and thymic and splenic CD4/CD8 lymphocyte subpopulations. Exposure to PYR did not alter splenic and thymus weight or splenic cellularity. However, 20 mg PYR/kg/day decreased thymic cellularity with decreases in both CD4+/CD8+ (20 mg/kg/day) and CD4-/CD8- (10 and 20 mg/kg/day) cell types. Functional immune assays indicated that lymphocyte proliferative responses and natural killer cell activity were normal; whereas exposure to PYR significantly decreased primary IgM antibody responses to a T-cell dependent antigen at the 1, 5, 10 and 20 mg/kg treatment levels for 14 days. This is the first study to examine the immunotoxicological effects of PYR and demonstrate that this compound selectively suppresses humoral antibody responses.
Immunology in the liver--from homeostasis to disease.
Heymann, Felix; Tacke, Frank
2016-02-01
The liver is a central immunological organ with a high exposure to circulating antigens and endotoxins from the gut microbiota, particularly enriched for innate immune cells (macrophages, innate lymphoid cells, mucosal-associated invariant T (MAIT) cells). In homeostasis, many mechanisms ensure suppression of immune responses, resulting in tolerance. Tolerance is also relevant for chronic persistence of hepatotropic viruses or allograft acceptance after liver transplantation. The liver can rapidly activate immunity in response to infections or tissue damage. Depending on the underlying liver disease, such as viral hepatitis, cholestasis or NASH, different triggers mediate immune-cell activation. Conserved mechanisms such as molecular danger patterns (alarmins), Toll-like receptor signalling or inflammasome activation initiate inflammatory responses in the liver. The inflammatory activation of hepatic stellate and Kupffer cells results in the chemokine-mediated infiltration of neutrophils, monocytes, natural killer (NK) and natural killer T (NKT) cells. The ultimate outcome of the intrahepatic immune response (for example, fibrosis or resolution) depends on the functional diversity of macrophages and dendritic cells, but also on the balance between pro-inflammatory and anti-inflammatory T-cell populations. As reviewed here, tremendous progress has helped to understand the fine-tuning of immune responses in the liver from homeostasis to disease, indicating promising targets for future therapies in acute and chronic liver diseases.
Swift, Brenna E; Williams, Brent A; Kosaka, Yoko; Wang, Xing-Hua; Medin, Jeffrey A; Viswanathan, Sowmya; Martinez-Lopez, Joaquin; Keating, Armand
2012-07-01
Novel therapies capable of targeting drug resistant clonogenic MM cells are required for more effective treatment of multiple myeloma. This study investigates the cytotoxicity of natural killer cell lines against bulk and clonogenic multiple myeloma and evaluates the tumor burden after NK cell therapy in a bioluminescent xenograft mouse model. The cytotoxicity of natural killer cell lines was evaluated against bulk multiple myeloma cell lines using chromium release and flow cytometry cytotoxicity assays. Selected activating receptors on natural killer cells were blocked to determine their role in multiple myeloma recognition. Growth inhibition of clonogenic multiple myeloma cells was assessed in a methylcellulose clonogenic assay in combination with secondary replating to evaluate the self-renewal of residual progenitors after natural killer cell treatment. A bioluminescent mouse model was developed using the human U266 cell line transduced to express green fluorescent protein and luciferase (U266eGFPluc) to monitor disease progression in vivo and assess bone marrow engraftment after intravenous NK-92 cell therapy. Three multiple myeloma cell lines were sensitive to NK-92 and KHYG-1 cytotoxicity mediated by NKp30, NKp46, NKG2D and DNAM-1 activating receptors. NK-92 and KHYG-1 demonstrated 2- to 3-fold greater inhibition of clonogenic multiple myeloma growth, compared with killing of the bulk tumor population. In addition, the residual colonies after treatment formed significantly fewer colonies compared to the control in a secondary replating for a cumulative clonogenic inhibition of 89-99% at the 20:1 effector to target ratio. Multiple myeloma tumor burden was reduced by NK-92 in a xenograft mouse model as measured by bioluminescence imaging and reduction in bone marrow engraftment of U266eGFPluc cells by flow cytometry. This study demonstrates that NK-92 and KHYG-1 are capable of killing clonogenic and bulk multiple myeloma cells. In addition, multiple myeloma tumor burden in a xenograft mouse model was reduced by intravenous NK-92 cell therapy. Since multiple myeloma colony frequency correlates with survival, our observations have important clinical implications and suggest that clinical studies of NK cell lines to treat MM are warranted.
Neely, Harold R; Mazo, Irina B; Gerlach, Carmen; von Andrian, Ulrich H
2017-12-18
Natural killer (NK) cells have historically been considered to be a part of the innate immune system, exerting a rapid response against pathogens and tumors in an antigen (Ag)-independent manner. However, over the past decade, evidence has accumulated suggesting that at least some NK cells display certain characteristics of adaptive immune cells. Indeed, NK cells can learn and remember encounters with a variety of Ags, including chemical haptens and viruses. Upon rechallenge, memory NK cells mount potent recall responses selectively to those Ags. This phenomenon, traditionally termed "immunological memory," has been reported in mice, nonhuman primates, and even humans and appears to be concentrated in discrete NK cell subsets. Because immunological memory protects against recurrent infections and is the central goal of active vaccination, it is crucial to define the mechanisms and consequences of NK cell memory. Here, we summarize the different kinds of memory responses that have been attributed to specific NK cell subsets and discuss the possibility to harness NK cell memory for vaccination purposes. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.
Que, Ri-Sheng; Lin, Cheng; Ding, Guo-Ping; Wu, Zheng-Rong; Cao, Li-Ping
2016-05-01
Tumor-derived exosomes were considered to be potential candidates for tumor vaccines because they are abundant in immune-regulating proteins, whereas tumor exosomal miRNAs may induce immune tolerance, thereby having an opposite immune function. This study was designed to separate exosomal protein and depleted exosomal microRNAs (miRNAs), increasing the immune activity of exosomes for activating dendritic cell/cytokine-induced killer cells (DC/CIKs) against pancreatic cancer (PC). PC-derived exosomes (PEs) were extracted from cultured PANC-1 cell supernatants and then ruptured; this was followed by ultrafiltered exosome lysates (UELs). DCs were stimulated with lipopolysaccharide (LPS), PE, and UEL, followed by co-culture with CIKs. The anti-tumor effects of DC/CIKs against PC were evaluated by proliferation and killing rates, tumor necrosis factor-α (TNF-α) and perforin secretion. Exosomal miRNAs were depleted after lysis and ultrafiltration, while 128 proteins were retained, including several immune-activating proteins. UEL-stimulated DC/CIKs showed a higher killing rate than LPS- and PE-stimulated DC/CIKs. miRNA-depleted exosome proteins may be promising agonists for specifically activating DC/CIKs against PC.
Orr, Mark T.; Sun, Joseph C.; Hesslein, David G.T.; Arase, Hisashi; Phillips, Joseph H.; Takai, Toshiyuki
2009-01-01
The activating natural killer (NK) cell receptor Ly49H recognizes the mouse cytomegalovirus (MCMV) m157 glycoprotein expressed on the surface of infected cells and is required for protection against MCMV. Although Ly49H has previously been shown to signal via DAP12, we now show that Ly49H must also associate with and signal via DAP10 for optimal function. In the absence of DAP12, DAP10 enables Ly49H-mediated killing of m157-bearing target cells, proliferation in response to MCMV infection, and partial protection against MCMV. DAP10-deficient Ly49H+ NK cells, expressing only Ly49H–DAP12 receptor complexes, are partially impaired in their ability to proliferate during MCMV infection, display diminished ERK1/2 activation, produce less IFN-γ upon Ly49H engagement, and demonstrate reduced control of MCMV infection. Deletion of both DAP10 and DAP12 completely abrogates Ly49H surface expression and control of MCMV infection. Thus, optimal NK cell–mediated immunity to MCMV depends on Ly49H signaling through both DAP10 and DAP12. PMID:19332875
Imaging immune surveillance of individual natural killer cells confined in microwell arrays.
Guldevall, Karolin; Vanherberghen, Bruno; Frisk, Thomas; Hurtig, Johan; Christakou, Athanasia E; Manneberg, Otto; Lindström, Sara; Andersson-Svahn, Helene; Wiklund, Martin; Önfelt, Björn
2010-11-12
New markers are constantly emerging that identify smaller and smaller subpopulations of immune cells. However, there is a growing awareness that even within very small populations, there is a marked functional heterogeneity and that measurements at the population level only gives an average estimate of the behaviour of that pool of cells. New techniques to analyze single immune cells over time are needed to overcome this limitation. For that purpose, we have designed and evaluated microwell array systems made from two materials, polydimethylsiloxane (PDMS) and silicon, for high-resolution imaging of individual natural killer (NK) cell responses. Both materials were suitable for short-term studies (<4 hours) but only silicon wells allowed long-term studies (several days). Time-lapse imaging of NK cell cytotoxicity in these microwell arrays revealed that roughly 30% of the target cells died much more rapidly than the rest upon NK cell encounter. This unexpected heterogeneity may reflect either separate mechanisms of killing or different killing efficiency by individual NK cells. Furthermore, we show that high-resolution imaging of inhibitory synapse formation, defined by clustering of MHC class I at the interface between NK and target cells, is possible in these microwells. We conclude that live cell imaging of NK-target cell interactions in multi-well microstructures are possible. The technique enables novel types of assays and allow data collection at a level of resolution not previously obtained. Furthermore, due to the large number of wells that can be simultaneously imaged, new statistical information is obtained that will lead to a better understanding of the function and regulation of the immune system at the single cell level.
Huang, George T.-J.; Zhang, Xinli; Park, No-Hee
2012-01-01
The intercellular adhesion molecule-1 (ICAM-1, CD54) serves as a counter-receptor for the β2-integrins, LFA-1 and Mac-1, which are expressed on leukocytes. Although expression of ICAM-1 on tumor cells has a role in tumor progression and development, information on ICAM-1 expression and its role in oral cancer has not been established. Normal human oral keratinocytes (NHOK), human papilloma virus (HPV)-immortalized human oral keratinocyte lines (HOK-16B, HOK-18A, and HOK-18C), and six human oral neoplastic cell lines (HOK-16B-BaP-T1, SCC-4, SCC-9, HEp-2, Tu-177 and 1483) were used to study ICAM-1 expression and its functional role in vitro. Our results demonstrated that NHOK express negligible levels of ICAM-1, whereas immortalized human oral keratinocytes and cancer cells express significantly higher levels of ICAM-1, except for HOK-16B-BaP-T1 and HEp-2. Altered mRNA half-lives did not fully account for the increased accumulation of ICAM-1 mRNA. Adhesion of peripheral blood mononuclear cells (PBMC) to epithelial cells correlated with cell surface ICAM-1 expression levels. This adhesion was inhibited by antibodies specific for either ICAM-1 or LFA-1/Mac-1, suggesting a role for these molecules in adhesion. In contrast, lymphokine-activated-killer (LAK) cell cytotoxic killing of epithelial cells did not correlate with ICAM-1 levels or with adhesion. Nonetheless, within each cell line, blocking of ICAM-1 or LFA-1/Mac-1 reduced LAK cells killing, suggesting that ICAM-1 is involved in mediating this killing. PMID:10938387
Oelsner, Sarah; Wagner, Juliane; Friede, Miriam E; Pfirrmann, Verena; Genßler, Sabrina; Rettinger, Eva; Buchholz, Christian J; Pfeifer, Heike; Schubert, Ralf; Ottmann, Oliver G; Ullrich, Evelyn; Bader, Peter; Wels, Winfried S
2016-10-15
Pre-emptive cancer immunotherapy by donor lymphocyte infusion (DLI) using cytokine-induced killer (CIK) cells may be beneficial to prevent relapse with a reduced risk of causing graft-versus-host-disease. CIK cells are a heterogeneous effector cell population including T cells (CD3(+) CD56(-) ), natural killer (NK) cells (CD3(-) CD56(+) ) and natural killer T (T-NK) cells (CD3(+) CD56(+) ) that exhibit non-major histocompatibility complex (MHC)-restricted cytotoxicity and are generated by ex vivo expansion of peripheral blood mononuclear cells in the presence of interferon (IFN)-γ, anti-CD3 antibody, interleukin-2 (IL-2) and interleukin-15 (IL-15). To facilitate selective target-cell recognition and enhance specific cytotoxicity against B-cell acute lymphoblastic leukemia (B-ALL), we transduced CIK cells with a lentiviral vector encoding a chimeric antigen receptor (CAR) that carries a composite CD28-CD3ζ domain for signaling and a CD19-specific scFv antibody fragment for cell binding (CAR 63.28.z). In vitro analysis revealed high and specific cell killing activity of CD19-targeted CIK/63.28.z cells against otherwise CIK-resistant cancer cell lines and primary B-ALL blasts, which was dependent on CD19 expression and CAR signaling. In a xenograft model in immunodeficient mice, treatment with CIK/63.28.z cells in contrast to therapy with unmodified CIK cells resulted in complete and durable molecular remissions of established primary pre-B-ALL. Our results demonstrate potent antileukemic activity of CAR-engineered CIK cells in vitro and in vivo, and suggest this strategy as a promising approach for adoptive immunotherapy of refractory pre-B-ALL. © 2016 UICC.
Yu, Jian-Bo; Zuo, Zhuo; Zhang, Wen-Yan; Yang, Qun-Pei; Zhang, Ying-Chun; Tang, Yuan; Zhao, Sha; Mo, Xian-Ming; Liu, Wei-Ping
2014-11-01
To analyze the differentiation characteristics of extranodal natural killer/T-cell lymphoma, nasal type, one nude mouse model, cell lines SNK6 and SNT8, and 16 fresh human samples were analyzed by flow cytometry immunophenotyping and immunohistochemistry staining; and 115 archived cases were used for phenotypic detection and prognostic analysis. We found that CD25 was expressed by most tumor cells in all samples, and CD56(+)CD25(+) cells were the predominant population in the mouse model, the 2 cell lines, and 10 of the 16 fresh tumor samples; in the other 6 fresh tumor samples, the predominant cell population was of the CD16(+)CD25(+) phenotype, and only a minor population showed the CD56(+)CD25(+) phenotype. The phenotype detected by immunohistochemistry staining generally was consistent with the phenotype found by flow cytometry immunophenotyping. According to the expression of CD56 and CD16, 115 cases could be classified into 3 phenotypic subtypes: CD56(-)CD16(-), CD56(+)CD16(-), and CD56(dim/-)CD16(+). Patients with tumors of the CD56(dim/-)CD16(+) phenotype had a poorer prognosis than patients with tumors of the other phenotypes. Differentiation of extranodal natural killer/T-cell lymphoma, nasal type apparently resembles the normal natural killer cell developmental pattern, and these tumors can be classified into 3 phenotypic subtypes of different aggressiveness. Expression of CD56(dim/-)CD16(+) implies a poorer prognosis. Copyright © 2014 Elsevier Inc. All rights reserved.
Bone marrow-resident NK cells prime monocytes for regulatory function during infection
Askenase, Michael H.; Han, Seong-Ji; Byrd, Allyson L.; da Fonseca, Denise Morais; Bouladoux, Nicolas; Wilhelm, Christoph; Konkel, Joanne E.; Hand, Timothy W.; Lacerda-Queiroz, Norinne; Su, Xin-Zhuan; Trinchieri, Giorgio; Grainger, John R.; Belkaid, Yasmine
2015-01-01
SUMMARY Tissue-infiltrating Ly6Chi monocytes play diverse roles in immunity, ranging from pathogen killing to immune regulation. How and where this diversity of function is imposed remains poorly understood. Here we show that during acute gastrointestinal infection, priming of monocytes for regulatory function preceded systemic inflammation and was initiated prior to bone marrow egress. Notably, natural killer (NK) cell-derived IFN-γ promoted a regulatory program in monocyte progenitors during development. Early bone marrow NK cell activation was controlled by systemic interleukin-12 (IL-12) produced by Batf3-dependent dendritic cells (DC) in the mucosal-associated lymphoid tissue (MALT). This work challenges the paradigm that monocyte function is dominantly imposed by local signals following tissue recruitment, and instead proposes a sequential model of differentiation in which monocytes are pre-emptively educated during development in the bone marrow to promote their tissue-specific function. PMID:26070484
Öz, Hasan H.; Zhou, Benyuan; Voss, Pina; Carevic, Melanie; Schroth, Carolin; Frey, Nina; Rieber, Nikolaus; Hector, Andreas; Hartl, Dominik
2016-01-01
Pseudomonas aeruginosa is an opportunistic pathogen that causes infections mainly in patients with cystic fibrosis (CF) lung disease. Despite innate and adaptive immune responses upon infection, P. aeruginosa is capable of efficiently escaping host defenses, but the underlying immune mechanisms remain poorly understood. Myeloid-derived suppressor cells (MDSCs) are innate immune cells that are functionally characterized by their potential to suppress T- and natural killer (NK)-cell responses. Here we demonstrate, using an airway in vivo infection model, that P. aeruginosa recruits and activates neutrophilic MDSCs, which functionally suppress T-cell responses. We further show that the CF gene defect (CF transmembrane conductance regulator, CFTR) modulates the functionality, but not the recruitment or generation of neutrophilic MDSCs. Collectively, we define a mechanism by which P. aeruginosa airway infection undermines host immunity by modulating neutrophilic MDSCs in vivo. PMID:27965936
Lane, Rhonda; Ghazi, Sabah O.; Whalen, Margaret M.
2009-01-01
This study investigated whether exposures to butyltins (BTs), tributylin (TBT) and dibutyltin (DBT) were able to alter cytosolic calcium levels in human natural killer (NK) cells. Additionally, the effects of cytosolic calcium ion increases on the activation state of mitogen activated protein kinases (MAPKs) in NK cells were also investigated. NK cells are an intital immune defense against the development of tumors or viral infections. TBT and DBT are widespread environmental contaminants, due to their various industrial applications. Both TBT and DBT have been shown to decrease the ability of NK cells to lyse tumor cells (lytic function). TBT has also been shown to activate MAPKs in NK cells. The results of this study indicated that TBT increased cytosolic calcium levels by as much as 100% after a 60 min exposure to 500 nM TBT while DBT increased cytosolic calcium levels to a much smaller extent (and required higher concentrations). The results also indicated that increases in cytosolic calcium could activate MAPKs but only for a short period of time (5 min), while previous studies showed that activation of MAPKs by TBT last for at least 6 hours. Thus, it appears that TBT stimulated increases in cytosolic calcium may contribute to, but are not fully responsible for, TBT-induced activation of MAPKs. PMID:19365649
CD56 Is a Pathogen Recognition Receptor on Human Natural Killer Cells.
Ziegler, Sabrina; Weiss, Esther; Schmitt, Anna-Lena; Schlegel, Jan; Burgert, Anne; Terpitz, Ulrich; Sauer, Markus; Moretta, Lorenzo; Sivori, Simona; Leonhardt, Ines; Kurzai, Oliver; Einsele, Hermann; Loeffler, Juergen
2017-07-21
Aspergillus (A.) fumigatus is an opportunistic fungal mold inducing invasive aspergillosis (IA) in immunocompromised patients. Although antifungal activity of human natural killer (NK) cells was shown in previous studies, the underlying cellular mechanisms and pathogen recognition receptors (PRRs) are still unknown. Using flow cytometry we were able to show that the fluorescence positivity of the surface receptor CD56 significantly decreased upon fungal contact. To visualize the interaction site of NK cells and A. fumigatus we used SEM, CLSM and dSTORM techniques, which clearly demonstrated that NK cells directly interact with A. fumigatus via CD56 and that CD56 is re-organized and accumulated at this interaction site time-dependently. The inhibition of the cytoskeleton showed that the receptor re-organization was an active process dependent on actin re-arrangements. Furthermore, we could show that CD56 plays a role in the fungus mediated NK cell activation, since blocking of CD56 surface receptor reduced fungal mediated NK cell activation and reduced cytokine secretion. These results confirmed the direct interaction of NK cells and A. fumigatus, leading to the conclusion that CD56 is a pathogen recognition receptor. These findings give new insights into the functional role of CD56 in the pathogen recognition during the innate immune response.
Viral Evasion of Natural Killer Cell Activation
Ma, Yi; Li, Xiaojuan; Kuang, Ersheng
2016-01-01
Natural killer (NK) cells play a key role in antiviral innate defenses because of their abilities to kill infected cells and secrete regulatory cytokines. Additionally, NK cells exhibit adaptive memory-like antigen-specific responses, which represent a novel antiviral NK cell defense mechanism. Viruses have evolved various strategies to evade the recognition and destruction by NK cells through the downregulation of the NK cell activating receptors. Here, we review the recent findings on viral evasion of NK cells via the impairment of NK cell-activating receptors and ligands, which provide new insights on the relationship between NK cells and viral actions during persistent viral infections. PMID:27077876
Viral Evasion of Natural Killer Cell Activation.
Ma, Yi; Li, Xiaojuan; Kuang, Ersheng
2016-04-12
Natural killer (NK) cells play a key role in antiviral innate defenses because of their abilities to kill infected cells and secrete regulatory cytokines. Additionally, NK cells exhibit adaptive memory-like antigen-specific responses, which represent a novel antiviral NK cell defense mechanism. Viruses have evolved various strategies to evade the recognition and destruction by NK cells through the downregulation of the NK cell activating receptors. Here, we review the recent findings on viral evasion of NK cells via the impairment of NK cell-activating receptors and ligands, which provide new insights on the relationship between NK cells and viral actions during persistent viral infections.
One approach to cancer immunotherapy, as opposed to therapeutic vaccination, is the transfusion of large numbers of tumor-specific killer T cells (cytotoxic T cells or CTLs) into patients. The body’s own defense killer T cells are a subgroup of T lymphocytes (a type of white blood cells) that are capable of inducing death in tumor cells. CTLs can cause the death of target cells either by releasing granules containing toxic molecules including perforin, or by producing a membrane protein called Fas ligand (FasL) which on interaction with the tumor cell results in cell death.
Sarkar, Saheli; Sabhachandani, Pooja; Ravi, Dashnamoorthy; Potdar, Sayalee; Purvey, Sneha; Beheshti, Afshin; Evens, Andrew M; Konry, Tania
2017-01-01
Natural killer (NK) cells are phenotypically and functionally diverse lymphocytes that recognize and kill cancer cells. The susceptibility of target cancer cells to NK cell-mediated cytotoxicity depends on the strength and balance of regulatory (activating/inhibitory) ligands expressed on target cell surface. We performed gene expression arrays to determine patterns of NK cell ligands associated with B-cell non-Hodgkin lymphoma (b-NHL). Microarray analyses revealed significant upregulation of a multitude of NK-activating and costimulatory ligands across varied b-NHL cell lines and primary lymphoma cells, including ULBP1, CD72, CD48, and SLAMF6. To correlate genetic signatures with functional anti-lymphoma activity, we developed a dynamic and quantitative cytotoxicity assay in an integrated microfluidic droplet generation and docking array. Individual NK cells and target lymphoma cells were co-encapsulated in picoliter-volume droplets to facilitate monitoring of transient cellular interactions and NK cell effector outcomes at single-cell level. We identified significant variability in NK-lymphoma cell contact duration, frequency, and subsequent cytolysis. Death of lymphoma cells undergoing single contact with NK cells occurred faster than cells that made multiple short contacts. NK cells also killed target cells in droplets via contact-independent mechanisms that partially relied on calcium-dependent processes and perforin secretion, but not on cytokines (interferon-γ or tumor necrosis factor-α). We extended this technique to characterize functional heterogeneity in cytolysis of primary cells from b-NHL patients. Tumor cells from two diffuse large B-cell lymphoma patients showed similar contact durations with NK cells; primary Burkitt lymphoma cells made longer contacts and were lysed at later times. We also tested the cytotoxic efficacy of NK-92, a continuously growing NK cell line being investigated as an antitumor therapy, using our droplet-based bioassay. NK-92 cells were found to be more efficient in killing b-NHL cells compared with primary NK cells, requiring shorter contacts for faster killing activity. Taken together, our combined genetic and microfluidic analysis demonstrate b-NHL cell sensitivity to NK cell-based cytotoxicity, which was associated with significant heterogeneity in the dynamic interaction at single-cell level.
Possible role of natural killer cells in pemphigus vulgaris − preliminary observations
Stern, J N H; Keskin, D B; Barteneva, N; Zuniga, J; Yunis, E J; Ahmed, A R
2008-01-01
Pemphigus vulgaris (PV) is an autoimmune blistering disease that affects the skin and multiple mucous membranes, and is caused by antibodies to desmoglein (Dsg) 1 and 3. Natural killer (NK) cells have a role in autoimmunity, but their role in PV is not known. NK cells in the peripheral blood leucocytes (PBL) of 15 untreated Caucasian patients with active PV were studied and compared with healthy controls for the expression of major histocompatibility complex (MHC) class II and co-stimulatory molecules. CD56+ CD16- CD3- NK or CD56+ CD16+ CD3- NK cells from the PBL of PV patients co-express MHC class II and co-stimulatory molecule B7-H3 without exogenous stimulation. CD4+ T cells from the PBL and perilesional skin of PV patients were co-cultured with CD56+ CD3- NK cells from the PBL of the same patients; in the presence of Dsg3 peptides underwent statistically significant proliferation, indicating that NK cells functioned as antigen-presenting cells. Supernatants from these co-cultures and serum of the same patients with active PV had statistically significantly elevated levels of interleukin (IL)-6, IL-8 and interferon-γ, compared with controls indicating that the NK cells stimulated CD4+ T cells to produce proinflammatory cytokines. In these experiments, we present preliminary evidence that NK cells may play a role in the pathobiology of PV. PMID:18373702
Walter, Lutz; Petersen, Beatrix
2017-02-01
The killer immunoglobulin-like receptors (KIR) as well as their MHC class I ligands display enormous genetic diversity and polymorphism in macaque species. Signals resulting from interaction between KIR or CD94/NKG2 receptors and their cognate MHC class I proteins essentially regulate the activity of natural killer (NK) cells. Macaque and human KIR share many features, such as clonal expression patterns, gene copy number variations, specificity for particular MHC class I allotypes, or epistasis between KIR and MHC class I genes that influence susceptibility and resistance to immunodeficiency virus infection. In this review article we also annotated publicly available rhesus macaque BAC clone sequences and provide the first description of the CD94-NKG2 genomic region. Besides the presence of genes that are orthologous to human NKG2A and NKG2F, this region contains three NKG2C paralogues. Hence, the genome of rhesus macaques contains moderately expanded and diversified NKG2 genes in addition to highly diversified KIR genes. The presence of two diversified NK cell receptor families in one species has not been described before and is expected to require a complex MHC-dependent regulation of NK cells. © 2016 John Wiley & Sons Ltd.
Target Strength of Southern Resident Killer Whales (Orcinus orca): Measurement and Modeling
DOE Office of Scientific and Technical Information (OSTI.GOV)
Xu, Jinshan; Deng, Zhiqun; Carlson, Thomas J.
2012-04-04
A major criterion for tidal power licensing in Washington’s Puget Sound is the management of the risk of injury to killer whales due to collision with moving turbine blades. An active monitoring system is being proposed for killer whale detection, tracking, and alerting that links to and triggers temporary turbine shutdown when there is risk of collision. Target strength (TS) modeling of the killer whale is critical to the design and application of any active monitoring system. A 1996 study performed a high-resolution measurement of acoustic reflectivity as a function of frequency of a female bottlenose dolphin (2.2 m length)more » at broadside aspect and TS as a function of incident angle at 67 kHz frequency. Assuming that killer whales share similar morphology structure with the bottlenose dolphin, we extrapolated the TS of an adult killer whale 7.5 m in length at 67 kHz frequency with -8 dB at broadside aspect and -28 dB at tail side. The backscattering data from three Southern Resident killer whales were analyzed to obtain the TS measurement. These data were collected at Lime Kiln State Park using a split-beam system deployed from a boat. The TS of the killer whale at higher frequency (200 kHz) was estimated based on a three-layer model for plane wave reflection from the lung of the whale. The TS data of killer whales were in good agreement with our model. In this paper, we also discuss and explain possible causes for measurement estimation error.« less
Psychosocial predictors of natural killer cell mobilization during marital conflict.
Miller, G E; Dopp, J M; Myers, H F; Stevens, S Y; Fahey, J L
1999-05-01
This study examined how specific emotions relate to autonomic nervous and immune system parameters and whether cynical hostility moderates this relationship. Forty-one married couples participated in a 15-min discussion about a marital problem. Observers recorded spouses' emotional expressions during the discussion, and cardiovascular, neuroendocrine, and immunologic parameters were assessed throughout the laboratory session. Among men high in cynical hostility, anger displayed during the conflict was associated with greater elevations in systolic and diastolic blood pressure, cortisol, and increases in natural killer cell numbers and cytotoxicity. Among men low in cynical hostility, anger was associated with smaller increases in heart rate and natural killer cell cytotoxicity. These findings suggest that models describing the impact of stress on physiology should be refined to reflect the joint contribution of situational and dispositional variables.
López-Cobo, Sheila; Romera-Cárdenas, Gema; García-Cuesta, Eva M; Reyburn, Hugh T; Valés-Gómez, Mar
2015-09-01
After immune interactions, membrane fragments can be transferred between cells. This fast transfer of molecules is transient and shows selectivity for certain proteins; however, the constraints underlying acquisition of a protein are unknown. To characterize the mechanism and functional consequences of this process in natural killer (NK) cells, we have compared the transfer of different NKG2D ligands. We show that human NKG2D ligands can be acquired by NK cells with different efficiencies. The main findings are that NKG2D ligand transfer is related to immune activation and receptor-ligand interaction and that NK cells acquire these proteins during interactions with target cells that lead to degranulation. Our results further demonstrate that NK cells that have acquired NKG2D ligands can stimulate activation of autologous NK cells. Surprisingly, NK cells can also re-transfer the acquired molecule to autologous effector cells during this immune recognition that leads to their death. These data demonstrate that transfer of molecules occurs as a consequence of immune recognition and imply that this process might play a role in homeostatic tuning-down of the immune response or be used as marker of interaction. © 2015 John Wiley & Sons Ltd.
The DNA methylation profile of activated human natural killer cells.
Wiencke, John K; Butler, Rondi; Hsuang, George; Eliot, Melissa; Kim, Stephanie; Sepulveda, Manuel A; Siegel, Derick; Houseman, E Andres; Kelsey, Karl T
2016-05-03
Natural killer (NK) cells are now recognized to exhibit characteristics akin to cells of the adaptive immune system. The generation of adaptive memory is linked to epigenetic reprogramming including alterations in DNA methylation. The study herein found reproducible genome wide DNA methylation changes associated with human NK cell activation. Activation led predominately to CpG hypomethylation (81% of significant loci). Bioinformatics analysis confirmed that non-coding and gene-associated differentially methylated sites (DMS) are enriched for immune related functions (i.e., immune cell activation). Known DNA methylation-regulated immune loci were also identified in activated NK cells (e.g., TNFA, LTA, IL13, CSF2). Twenty-one loci were designated high priority and further investigated as potential markers of NK activation. BHLHE40 was identified as a viable candidate for which a droplet digital PCR assay for demethylation was developed. The assay revealed high demethylation in activated NK cells and low demethylation in naïve NK, T- and B-cells. We conclude the NK cell methylome is plastic with potential for remodeling. The differentially methylated region signature of activated NKs revealed similarities with T cell activation, but also provided unique biomarker candidates of NK activation, which could be useful in epigenome-wide association studies to interrogate the role of NK subtypes in global methylation changes associated with exposures and/or disease states.
T-cell lymphomas in South america and europe.
Bellei, Monica; Chiattone, Carlos Sergio; Luminari, Stefano; Pesce, Emanuela Anna; Cabrera, Maria Elena; de Souza, Carmino Antonio; Gabús, Raul; Zoppegno, Lucia; Zoppegno, Lucia; Milone, Jorge; Pavlovsky, Astrid; Connors, Joseph Michael; Foss, Francine Mary; Horwitz, Steven Michael; Liang, Raymond; Montoto, Silvia; Pileri, Stefano Aldo; Polliack, Aaron; Vose, Julie Marie; Zinzani, Pier Luigi; Zucca, Emanuele; Federico, Massimo
2012-01-01
Peripheral T-cell lymphomas are a group of rare neoplasms originating from clonal proliferation of mature post-thymic lymphocytes with different entities having specific biological characteristics and clinical features. As natural killer cells are closely related to T-cells, natural killer-cell lymphomas are also part of the group. The current World Health Organization classification recognizes four categories of T/natural killer-cell lymphomas with respect to their presentation: disseminated (leukemic), nodal, extranodal and cutaneous. Geographic variations in the distribution of these diseases are well documented: nodal subtypes are more frequent in Europe and North America, while extranodal forms, including natural killer-cell lymphomas, occur almost exclusively in Asia and South America. On the whole, T-cell lymphomas are more common in Asia than in western countries, usually affect adults, with a higher tendency in men, and, excluding a few subtypes, usually have an aggressive course and poor prognosis. Apart from anaplastic lymphoma kinase-positive anaplastic large cell lymphoma, that have a good outcome, other nodal and extranodal forms have a 5-year overall survival of about 30%. According to the principal prognostic indexes, the majority of patients are allocated to the unfavorable subset. In the past, the rarity of these diseases prevented progress in the understanding of their biology and improvements in the efficaciousness of therapy. Recently, international projects devoted to these diseases created networks promoting investigations on T-cell lymphomas. These projects are the basis of forthcoming cooperative, large scale trials to detail biologic characteristics of each sub-entity and to possibly individuate targets for new therapies.
T-Cell Lymphomas in South America and Europe
Bellei, Monica; Chiattone, Carlos Sergio; Luminari, Stefano; Pesce, Emanuela Anna; Cabrera, Maria Elena; de Souza, Carmino Antonio; Gabús, Raul; Zoppegno, Lucia; Zoppegno, Lucia; Milone, Jorge; Pavlovsky, Astrid; Connors, Joseph Michael; Foss, Francine Mary; Horwitz, Steven Michael; Liang, Raymond; Montoto, Silvia; Pileri, Stefano Aldo; Polliack, Aaron; Vose, Julie Marie; Zinzani, Pier Luigi; Zucca, Emanuele; Federico, Massimo
2012-01-01
Peripheral T-cell lymphomas are a group of rare neoplasms originating from clonal proliferation of mature post-thymic lymphocytes with different entities having specific biological characteristics and clinical features. As natural killer cells are closely related to T-cells, natural killer-cell lymphomas are also part of the group. The current World Health Organization classification recognizes four categories of T/natural killer-cell lymphomas with respect to their presentation: disseminated (leukemic), nodal, extranodal and cutaneous. Geographic variations in the distribution of these diseases are well documented: nodal subtypes are more frequent in Europe and North America, while extranodal forms, including natural killer-cell lymphomas, occur almost exclusively in Asia and South America. On the whole, T-cell lymphomas are more common in Asia than in western countries, usually affect adults, with a higher tendency in men, and, excluding a few subtypes, usually have an aggressive course and poor prognosis. Apart from anaplastic lymphoma kinase-positive anaplastic large cell lymphoma, that have a good outcome, other nodal and extranodal forms have a 5-year overall survival of about 30%. According to the principal prognostic indexes, the majority of patients are allocated to the unfavorable subset. In the past, the rarity of these diseases prevented progress in the understanding of their biology and improvements in the efficaciousness of therapy. Recently, international projects devoted to these diseases created networks promoting investigations on T-cell lymphomas. These projects are the basis of forthcoming cooperative, large scale trials to detail biologic characteristics of each sub-entity and to possibly individuate targets for new therapies. PMID:23049383
Generation of natural killer cells from hematopoietic stem cells in vitro for immunotherapy
Luevano, Martha; Madrigal, Alejandro; Saudemont, Aurore
2012-01-01
Natural killer (NK) cells are part of the innate immune system and are an alluring option for immunotherapy due to their ability to kill infected cells or cancer cells without prior sensitization. Throughout the past 20 years, different groups have been able to reproduce NK cell development in vitro, and NK cell ontogeny studies have provided the basis for the establishment of protocols to produce NK cells in vitro for immunotherapy. Here, we briefly discuss NK cell development and NK cell immunotherapy approaches. We review the factors needed for NK cell differentiation in vitro, which stem cell sources have been used, published protocols, challenges and future directions for Good Manufacturing Practice protocols. PMID:22705914
Ocular anatomy, ganglion cell distribution and retinal resolution of a killer whale (Orcinus orca).
Mass, Alla M; Supin, Alexander Y; Abramov, Andrey V; Mukhametov, Lev M; Rozanova, Elena I
2013-01-01
Retinal topography, cell density and sizes of ganglion cells in the killer whale (Orcinus orca) were analyzed in retinal whole mounts stained with cresyl violet. A distinctive feature of the killer whale's retina is the large size of ganglion cells and low cell density compared to terrestrial mammals. The ganglion cell diameter ranged from 8 to 100 µm, with the majority of cells within a range of 20-40 µm. The topographic distribution of ganglion cells displayed two spots of high cell density located in the temporal and nasal quadrants, 20 mm from the optic disk. The high-density areas were connected by a horizontal belt-like area passing below the optic disk of the retina. Peak cell densities in these areas were evaluated. Mean peak cell densities were 334 and 288 cells/mm(2) in the temporal and nasal high-density areas, respectively. With a posterior nodal distance of 19.5 mm, these high-density data predict a retinal resolution of 9.6' (3.1 cycles/deg.) and 12.6' (2.4 cycles/deg.) in the temporal and nasal areas, respectively, in water. Copyright © 2012 S. Karger AG, Basel.
Adoptive natural killer cell therapy is effective in reducing pulmonary metastasis of Ewing sarcoma
Tong, Alexander A.; Hashem, Hasan; Eid, Saada; Allen, Frederick; Kingsley, Daniel
2017-01-01
ABSTRACT The survival of patients with metastatic or relapsed Ewing sarcoma (ES) remains dismal despite intensification of combination chemotherapy and radiotherapy, precipitating the need for novel alternative therapies with minimal side effects. Natural killer (NK) cells are promising additions to the field of cellular immunotherapy. Adoptive NK cell therapy has shown encouraging results in hematological malignancies. Despite these initial promising successes, however, NK cell therapy for solid tumors remains to be investigated using in vivo tumor models. The purpose of this study is to evaluate the efficacy of ex vivo expanded human NK cells in controlling primary and metastatic ES tumor growth in vitro and in vivo. Using membrane-bound IL-21 containing K562 (K562-mbIL-21) expansion platform, we were able to obtain sufficient numbers of expanded NK (eNK) cells that display favorable activation phenotypes and inflammatory cytokine secretion, along with a strong in vitro cytotoxic effect against ES. Furthermore, eNK therapy significantly decreased lung metastasis without any significant therapeutic effect in limiting primary tumor growth in an in vivo xenograft model. Our data demonstrate that eNK may be effective against pulmonary metastatic ES, but challenges remain to direct proper trafficking and augmenting the cytotoxic function of eNK to target primary tumor sites. PMID:28507811
Shatskikh, O A; Luzikova, E M
2012-01-01
The aim this investigation was to study the changes in the numbers of spleen CD57+ and CD68+ cells (natural killer cells and macrophages respectively) after melatonin administration to the animals kept on different illumination regimens. The experimental animals were given melatonin in dose of 0.03 mg per day for 2 and 4 weeks under conditions of natural illumination or artificial darkening. Spleen paraffin sections were stained using immunohistochemical methods for detection of CD57+ and CD68+ cells. It was shown that long-term administration of melatonin under conditions of natural illumination had an immunosuppressive effect, that was manifested by the depopulation of the marginal zones, white pulp and all the zones of the red pulp, parenchyma loosening and denudation of the reticular stroma of the organ. However, long-term hormone administration under conditions of artificial darkening had an immunostimulatory effect as evidenced by the increased inflow of immunocompetent cells into the spleen, their migration from the white pulp into the marginal zones and emigration into peripheral blood flow, concomitant with the increase in the number of lymphoid nodules. The number of CD57+ and CD68+ cells was increased in splenic periarterial lymphoid sheaths and decreased in B-dependent zones of the organ.
Schellhorn, Melina; Haustein, Maria; Frank, Marcus; Linnebacher, Michael; Hinz, Burkhard
2015-11-17
The antitumorigenic mechanism of the selective cyclooxygenase-2 (COX-2) inhibitor celecoxib is still a matter of debate. Using lung cancer cell lines (A549, H460) and metastatic cells derived from a lung cancer patient, the present study investigates the impact of celecoxib on the expression of intercellular adhesion molecule 1 (ICAM-1) and cancer cell lysis by lymphokine-activated killer (LAK) cells. Celecoxib, but not other structurally related selective COX-2 inhibitors (i.e., etoricoxib, rofecoxib, valdecoxib), was found to cause a substantial upregulation of ICAM-1 protein levels. Likewise, ICAM-1 mRNA expression was increased by celecoxib. Celecoxib enhanced the susceptibility of cancer cells to be lysed by LAK cells with the respective effect being reversed by a neutralizing ICAM-1 antibody. In addition, enhanced killing of celecoxib-treated cancer cells was reversed by preincubation of LAK cells with an antibody to lymphocyte function associated antigen 1 (LFA-1), suggesting intercellular ICAM-1/LFA-1 crosslink as crucial event within this process. Finally, celecoxib elicited no significant increase of LAK cell-mediated lysis of non-tumor bronchial epithelial cells, BEAS-2B, associated with a far less ICAM-1 induction as compared to cancer cells. Altogether, our data demonstrate celecoxib-induced upregulation of ICAM-1 on lung cancer cells to be responsible for intercellular ICAM-1/LFA-1 crosslink that confers increased cancer cell lysis by LAK cells. These findings provide proof for a novel antitumorigenic mechanism of celecoxib.
Frank, Marcus; Linnebacher, Michael; Hinz, Burkhard
2015-01-01
The antitumorigenic mechanism of the selective cyclooxygenase-2 (COX-2) inhibitor celecoxib is still a matter of debate. Using lung cancer cell lines (A549, H460) and metastatic cells derived from a lung cancer patient, the present study investigates the impact of celecoxib on the expression of intercellular adhesion molecule 1 (ICAM-1) and cancer cell lysis by lymphokine-activated killer (LAK) cells. Celecoxib, but not other structurally related selective COX-2 inhibitors (i.e., etoricoxib, rofecoxib, valdecoxib), was found to cause a substantial upregulation of ICAM-1 protein levels. Likewise, ICAM-1 mRNA expression was increased by celecoxib. Celecoxib enhanced the susceptibility of cancer cells to be lysed by LAK cells with the respective effect being reversed by a neutralizing ICAM-1 antibody. In addition, enhanced killing of celecoxib-treated cancer cells was reversed by preincubation of LAK cells with an antibody to lymphocyte function associated antigen 1 (LFA-1), suggesting intercellular ICAM-1/LFA-1 crosslink as crucial event within this process. Finally, celecoxib elicited no significant increase of LAK cell-mediated lysis of non-tumor bronchial epithelial cells, BEAS-2B, associated with a far less ICAM-1 induction as compared to cancer cells. Altogether, our data demonstrate celecoxib-induced upregulation of ICAM-1 on lung cancer cells to be responsible for intercellular ICAM-1/LFA-1 crosslink that confers increased cancer cell lysis by LAK cells. These findings provide proof for a novel antitumorigenic mechanism of celecoxib. PMID:26513172
Sanderson, Nicholas D.; Norman, Paul J.; Guethlein, Lisbeth A.; Ellis, Shirley A.; Williams, Christina; Breen, Matthew; Park, Steven D. E.; Magee, David A.; Babrzadeh, Farbod; Warry, Andrew; Watson, Mick; Bradley, Daniel G.; MacHugh, David E.; Parham, Peter
2014-01-01
Under selection pressure from pathogens, variable NK cell receptors that recognize polymorphic MHC class I evolved convergently in different species of placental mammal. Unexpectedly, diversified killer cell Ig–like receptors (KIRs) are shared by simian primates, including humans, and cattle, but not by other species. Whereas much is known of human KIR genetics and genomics, knowledge of cattle KIR is limited to nine cDNA sequences. To facilitate comparison of the cattle and human KIR gene families, we determined the genomic location, structure, and sequence of two cattle KIR haplotypes and defined KIR sequences of aurochs, the extinct wild ancestor of domestic cattle. Larger than its human counterpart, the cattle KIR locus evolved through successive duplications of a block containing ancestral KIR3DL and KIR3DX genes that existed before placental mammals. Comparison of two cattle KIR haplotypes and aurochs KIR show the KIR are polymorphic and the gene organization and content appear conserved. Of 18 genes, 8 are functional and 10 were inactivated by point mutation. Selective inactivation of KIR3DL and activating receptor genes leaves a functional cohort of one inhibitory KIR3DL, one activating KIR3DX, and six inhibitory KIR3DX. Functional KIR diversity evolved from KIR3DX in cattle and from KIR3DL in simian primates. Although independently evolved, cattle and human KIR gene families share important function-related properties, indicating that cattle KIR are NK cell receptors for cattle MHC class I. Combinations of KIR and MHC class I are the major genetic factors associated with human disease and merit investigation in cattle. PMID:25398326
Kee, Ji-Ye; Arita, Yoshihisa; Shinohara, Kanna; Ohashi, Yasukata; Sakurai, Hiroaki; Saiki, Ikuo; Koizumi, Keiichi
2013-01-01
Due to their chemoattractant properties stimulating the accumulation of infiltrating immune cells in tumors, chemokines are known to have antitumor effects. Fractalkine, a unique CX3C chemokine, is expressed in activated endothelial cells, while its receptor, CX3CR1, is expressed in cytolytic immune cells, such as natural killer cells, monocytes and some CD8 + T cells. The biological properties of cancer cells are affected by the implantation organ and differences in immune systems, requiring cancer implantation in orthotopic organs in an in vivo experiment. To develop new therapy strategies for lung cancer, an animal model reflecting the clinical features of lung cancer was previously established. This study aimed to determine whether CX3CL1-induced biological functions should be used for immune cell-based gene therapy of lung cancer in the orthotopic implantation model. An orthotopic intrapulmonary implantation of CX3CL1-stable expression in mouse lung cancer (LLC-CX3CL1) was performed to analyze growth. Results showed a significant decrease in tumor growth in the lung compared to the control cells (LLC-mock). Furthermore, the antitumor effects of CX3CL1 were derived from natural killer cell activities in the depletion experiment in vivo . Therefore, CX3CL1 has the potential of a useful therapeutic target in lung cancer.
Zhang, Jiqing; Tai, Lee-Hwa; Ilkow, Carolina S; Alkayyal, Almohanad A; Ananth, Abhirami A; de Souza, Christiano Tanese; Wang, Jiahu; Sahi, Shalini; Ly, Lundi; Lefebvre, Charles; Falls, Theresa J; Stephenson, Kyle B; Mahmoud, Ahmad B; Makrigiannis, Andrew P; Lichty, Brian D; Bell, John C; Stojdl, David F; Auer, Rebecca C
2014-01-01
This study characterizes the ability of novel oncolytic rhabdoviruses (Maraba MG1) to boost natural killer (NK) cell activity. Our results demonstrate that MG1 activates NK cells via direct infection and maturation of conventional dendritic cells. Using NK depletion and conventional dendritic cells ablation studies in vivo, we established that both are required for MG1 efficacy. We further explored the efficacy of attenuated MG1 (nonreplicating MG1-UV2min and single-cycle replicating MG1-Gless) and demonstrated that these viruses activate conventional dendritic cells, although to a lesser extent than live MG1. This translates to equivalent abilities to remove tumor metastases only at the highest viral doses of attenuated MG1. In tandem, we characterized the antitumor ability of NK cells following preoperative administration of live and attenuated MG1. Our results demonstrates that a similar level of NK activation and reduction in postoperative tumor metastases was achieved with equivalent high viral doses concluding that viral replication is important, but not necessary for NK activation. Biochemical characterization of a panel of UV-inactivated MG1 (2–120 minutes) revealed that intact viral particle and target cell recognition are essential for NK cell–mediated antitumor responses. These findings provide mechanistic insight and preclinical rationale for safe perioperative virotherapy to effectively reduce metastatic disease following cancer surgery. PMID:24695102
Van den Bergh, Johan M J; Guerti, Khadija; Willemen, Yannick; Lion, Eva; Cools, Nathalie; Goossens, Herman; Vorsters, Alex; Van Tendeloo, Viggo F I; Anguille, Sébastien; Van Damme, Pierre; Smits, Evelien L J M
2014-01-01
Cervarix™ is approved as a preventive vaccine against infection with the human papillomavirus (HPV) strains 16 and 18, which are causally related to the development of cervical cancer. We are the first to investigate in vitro the effects of this HPV vaccine on interleukin (IL)-15 dendritic cells (DC) as proxy of a naturally occurring subset of blood DC, and natural killer (NK) cells, two innate immune cell types that play an important role in antitumour immunity. Our results show that exposure of IL-15 DC to the HPV vaccine results in increased expression of phenotypic maturation markers, pro-inflammatory cytokine production and cytotoxic activity against HPV-positive tumour cells. These effects are mediated by the vaccine adjuvant, partly through Toll-like receptor 4 activation. Next, we demonstrate that vaccine-exposed IL-15 DC in turn induce phenotypic activation of NK cells, resulting in a synergistic cytotoxic action against HPV-infected tumour cells. Our study thus identifies a novel mode of action of the HPV vaccine in boosting innate immunity, including killing of HPV-infected cells by DC and NK cells. PMID:24979331
Blum, Stefan; Csurhes, Peter; McCombe, Pamela
2015-08-15
Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an acquired inflammatory neuropathy, which has similar clinical and pathological features to Guillain-Barré Syndrome (GBS), but differs in time course. We investigated the frequency of genes encoding Killer immunoglobulin-like receptors and their HLA ligands in subjects with CIDP, in subjects with GBS and in healthy controls. There were no differences in KIR gene frequency among the 3 groups. The gene frequencies for HLA-B Bw4-I were significantly greater in CIDP than HC, but did not differ from GBS. The frequency of the combination of 3DL1/HLA-B Bw4I was greater in CIDP than HC, but did not differ from that of GBS. These data raise the possibility of NK cell function being an important factor in the pathogenesis of CIDP. Copyright © 2015 Elsevier B.V. All rights reserved.
Hemophagocytic lymphohistiocytosis secondary to T-cell/histiocyte-rich large B-cell lymphoma
Devitt, Katherine; Cerny, Jan; Switzer, Bradley; Ramanathan, Muthalagu; Nath, Rajneesh; Yu, Hongbo; Woda, Bruce A.; Chen, Benjamin J.
2014-01-01
Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening clinical syndrome characterized by dysregulation of the immune system. Impaired function of cytotoxic T cells and natural killer cells is often seen, and T-cell malignancies represent most cases of lymphoma-associated HLH. HLH associated with B-cell lymphoma is rare. We describe a case of a 30-year-old man who presented with fever, splenomegaly, and hyperferritinemia. Bone marrow biopsy revealed T-cell/histiocyte-rich large B-cell lymphoma, a rare, aggressive B-cell malignancy. This case highlights the interplay between a pro-inflammatory cytokine microenvironment and tumor-mediated immune suppression, and addresses the importance of accurately diagnosing these entities for appropriate clinical management. PMID:24955327
Hemophagocytic lymphohistiocytosis secondary to T-cell/histiocyte-rich large B-cell lymphoma.
Devitt, Katherine; Cerny, Jan; Switzer, Bradley; Ramanathan, Muthalagu; Nath, Rajneesh; Yu, Hongbo; Woda, Bruce A; Chen, Benjamin J
2014-01-01
Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening clinical syndrome characterized by dysregulation of the immune system. Impaired function of cytotoxic T cells and natural killer cells is often seen, and T-cell malignancies represent most cases of lymphoma-associated HLH. HLH associated with B-cell lymphoma is rare. We describe a case of a 30-year-old man who presented with fever, splenomegaly, and hyperferritinemia. Bone marrow biopsy revealed T-cell/histiocyte-rich large B-cell lymphoma, a rare, aggressive B-cell malignancy. This case highlights the interplay between a pro-inflammatory cytokine microenvironment and tumor-mediated immune suppression, and addresses the importance of accurately diagnosing these entities for appropriate clinical management.
Regulatory T cells decrease invariant natural killer T cell-mediated pregnancy loss in mice.
Li, L; Tu, J; Jiang, Y; Zhou, J; Schust, D J
2017-05-01
Pregnancy loss is the commonest complication of pregnancy. The causes of pregnancy loss are poorly understood. It has been reported that stimulation of invariant natural killer T (iNKT) cells using α-galactosylceramide (αGC) induces pregnancy loss in mice. Here we investigated the mechanisms, especially the role of regulatory T (Treg) cells, in iNKT cell-mediated pregnancy loss. We found that injection of αGC rapidly induced fetal resorption, activated decidual iNKT cells, decreased the percentage of decidual Treg cells and their interleukin (IL)-10 and transforming growth factor (TGF)-β production, and upregulated the levels of interferon (IFN)-γ, tumor necrosis factor-α, IL-4, and IL-10 in serum. Adoptive transfer of iNKT cells from wild-type (WT) and IL-4 -/- mice but not IFN-γ -/- mice into αGC-treated iNKT cell-deficient Jα18 -/- mice restored αGC-induced pregnancy loss. Adoptive transfer of Treg cells downregulated α-GC-induced pregnancy loss in WT mice. Finally, co-culture with αGC-stimulated decidual iNKT cells decreased the production of IL-10 and TGF-β in decidual Treg cells and inhibited their suppressive activity. These findings suggest that activation of iNKT cells induces pregnancy loss in mice in an IFN-γ-dependent manner. In addition, inhibition of the function of decidual Treg cells has an important role in iNKT cell-mediated pregnancy loss.
Norman, Paul J.; Hollenbach, Jill A.; Nemat-Gorgani, Neda; Guethlein, Lisbeth A.; Hilton, Hugo G.; Pando, Marcelo J.; Koram, Kwadwo A.; Riley, Eleanor M.; Abi-Rached, Laurent; Parham, Peter
2013-01-01
Interactions between HLA class I molecules and killer-cell immunoglobulin-like receptors (KIR) control natural killer cell (NK) functions in immunity and reproduction. Encoded by genes on different chromosomes, these polymorphic ligands and receptors correlate highly with disease resistance and susceptibility. Although studied at low-resolution in many populations, high-resolution analysis of combinatorial diversity of HLA class I and KIR is limited to Asian and Amerindian populations with low genetic diversity. At the other end of the spectrum is the West African population investigated here: we studied 235 individuals, including 104 mother-child pairs, from the Ga-Adangbe of Ghana. This population has a rich diversity of 175 KIR variants forming 208 KIR haplotypes, and 81 HLA-A, -B and -C variants forming 190 HLA class I haplotypes. Each individual we studied has a unique compound genotype of HLA class I and KIR, forming 1–14 functional ligand-receptor interactions. Maintaining this exceptionally high polymorphism is balancing selection. The centromeric region of the KIR locus, encoding HLA-C receptors, is highly diverse whereas the telomeric region encoding Bw4-specific KIR3DL1, lacks diversity in Africans. Present in the Ga-Adangbe are high frequencies of Bw4-bearing HLA-B*53:01 and Bw4-lacking HLA-B*35:01, which otherwise are identical. Balancing selection at key residues maintains numerous HLA-B allotypes having and lacking Bw4, and also those of stronger and weaker interaction with LILRB1, a KIR-related receptor. Correspondingly, there is a balance at key residues of KIR3DL1 that modulate its level of cell-surface expression. Thus, capacity to interact with NK cells synergizes with peptide binding diversity to drive HLA-B allele frequency distribution. These features of KIR and HLA are consistent with ongoing co-evolution and selection imposed by a pathogen endemic to West Africa. Because of the prevalence of malaria in the Ga-Adangbe and previous associations of cerebral malaria with HLA-B*53:01 and KIR, Plasmodium falciparum is a candidate pathogen. PMID:24204327
CD11c identifies a subset of murine liver natural killer cells that responds to adenoviral hepatitis
Burt, Bryan M.; Plitas, George; Stableford, Jennifer A.; Nguyen, Hoang M.; Bamboat, Zubin M.; Pillarisetty, Venu G.; DeMatteo, Ronald P.
2008-01-01
The liver contains a unique repertoire of immune cells and a particular abundance of NK cells. We have found that CD11c defines a distinct subset of NK cells (NK1.1+CD3−) in the murine liver whose function was currently unknown. In naïve animals, CD11c+ liver NK cells displayed an activated phenotype and possessed enhanced effector functions when compared with CD11c− liver NK cells. During the innate response to adenovirus infection, CD11c+ NK cells were the more common IFN-γ-producing NK cells in the liver, demonstrated enhanced lytic capability, and gained a modest degree of APC function. The mechanism of IFN-γ production in vivo depended on TLR9 ligation as well as IL-12 and -18. Taken together, our findings demonstrate that CD11c+ NK cells are a unique subset of NK cells in the murine liver that contribute to the defense against adenoviral hepatitis. PMID:18664530
STATs in NK-Cells: The Good, the Bad, and the Ugly.
Gotthardt, Dagmar; Sexl, Veronika
2016-01-01
Natural killer (NK)-cells are major players in the fight against viral infections and transformed cells, but there is increasing evidence attributing a disease-promoting role to NK-cells. Cytokines present in the tumor microenvironment shape NK-cell maturation, function, and effector responses. Many cytokines signal via the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway that is also frequently altered and constitutively active in a broad range of tumor cells. As a consequence, there are currently major efforts to develop therapeutic strategies to target this pathway. Therefore, it is of utmost importance to understand the role and contributions of JAK-STAT molecules in NK-cell biology-only this knowledge will allow us to predict effects of JAK-STAT inhibition for NK-cell functions and to successfully apply precision medicine. We will review the current knowledge on the role of JAK-STAT signaling for NK-cell functions and discuss conditions involved in the switch from NK-cell tumor surveillance to disease promotion.
Helinski, E H; Hurley, E L; Streck, R J; Bielat, K L; Pauly, J L
1990-01-01
Tumor-cytolytic lymphokine (e.g., interleukin-2; IL-2)-activated killer cells are currently being evaluated in IL-2/LAK cell adoptive immunotherapy regimens for the treatment of cancer. Monocyte-derived macrophages (M phi) are also known to be efficient tumor killer cells; accordingly, M phi that have been activated in vitro may also be of therapeutic merit. However, attempts to cultivate M phi for morphological and functional studies have often been compromised because M phi adhere rapidly and tenaciously to cultureware. Studies that we have conducted to address this problem have proven successful in developing procedures for the long-term cultivation of non-adherent immunocompetent M phi in serum-free medium using petri dishes containing a thin Teflon liner. The utility of this technology is documented by the results of studies presented herein in which light and scanning electron microscopy was used to analyze tumor-cytolytic human M phi. In these experiments, we demonstrated that nonadherent immunocompetent human M phi can be prepared for detailed examinations of their pleomorphic membrane architecture. Moreover, nonadherent human M phi could readily be collected for preparing conjugates of M phi and tumor cells. It is anticipated that this technology should prove useful for future structure-function studies defining the topographical location and spatial distribution of antigens and receptors on M phi membrane ultrastructures, particularly the microvilli-like projections that bridge together an immunocompetent effector M phi and target cell (e.g., tumor cells and microbial pathogens) and which provide the physical interaction required for the initial phases of a cellular immune response that includes antigen recognition and cell-to-cell adhesion.
Stephen, Sasha; Morrissey, Kelly A; Benoit, Bernice M; Kim, Ellen J; Vittorio, Carmela C; Nasta, Sunita D; Showe, Louise C; Wysocka, Maria; Rook, Alain H
2012-02-01
Several histone deacetylase inhibitors (HDACi), including vorinostat, have been approved for the therapy of cutaneous T-cell lymphoma (CTCL). Emerging data suggest that HDACi may exert immune suppressive effects which would be disadvantageous for therapy of CTCL. We describe a patient with Sezary syndrome who was monitored for drug-induced immunosuppression while undergoing treatment with vorinostat. Analysis of the patient's natural killer cell function before and after initiation of treatment confirmed inhibition of this important cell-mediated immune function. In addition, the in vitro effects of vorinostat on the immunity of healthy volunteers confirmed that this class of drug can profoundly suppress multiple arms of the cellular immune response. These findings raise concerns of increased susceptibility to infection in this high-risk population.
Suppressing the killer instinct.
Campbell, Kerry S
2016-05-24
Natural killer (NK) cells are innate lymphoid cells that have adopted activating and inhibitory signaling mechanisms enabling them to be tolerant of normal cells but to distinguish and eliminate tumor cells and virus-infected cells. In this issue of Science Signaling, Matalon et al show how inhibitory receptors disrupt NK cell activation by stimulating dephosphorylation of the adaptor protein LAT (linker of activated T cells) and phospholipase C-γ by the phosphatase SHP-1 [Src homology 2 (SH2) domain-containing protein tyrosine phosphatase 1], as well as ubiquitylation of LAT by Cbl family E3 ubiquitin ligases. Copyright © 2016, American Association for the Advancement of Science.
Retroviral expression screening of oncogenes in natural killer cell leukemia.
Choi, Young Lim; Moriuchi, Ryozo; Osawa, Mitsujiro; Iwama, Atsushi; Makishima, Hideki; Wada, Tomoaki; Kisanuki, Hiroyuki; Kaneda, Ruri; Ota, Jun; Koinuma, Koji; Ishikawa, Madoka; Takada, Shuji; Yamashita, Yoshihiro; Oshimi, Kazuo; Mano, Hiroyuki
2005-08-01
Aggressive natural killer cell leukemia (ANKL) is an intractable malignancy that is characterized by the outgrowth of NK cells. To identify transforming genes in ANKL, we constructed a retroviral cDNA expression library from an ANKL cell line KHYG-1. Infection of 3T3 cells with recombinant retroviruses yielded 33 transformed foci. Nucleotide sequencing of the DNA inserts recovered from these foci revealed that 31 of them encoded KRAS2 with a glycine-to-alanine mutation at codon 12. Mutation-specific PCR analysis indicated that the KRAS mutation was present only in KHYG-1 cells, not in another ANKL cell line or in clinical specimens (n=8).
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.
Positive selection on the killer whale mitogenome.
Foote, Andrew D; Morin, Phillip A; Durban, John W; Pitman, Robert L; Wade, Paul; Willerslev, Eske; Gilbert, M Thomas P; da Fonseca, Rute R
2011-02-23
Mitochondria produce up to 95 per cent of the eukaryotic cell's energy. The coding genes of the mitochondrial DNA may therefore evolve under selection owing to metabolic requirements. The killer whale, Orcinus orca, is polymorphic, has a global distribution and occupies a range of ecological niches. It is therefore a suitable organism for testing this hypothesis. We compared a global dataset of the complete mitochondrial genomes of 139 individuals for amino acid changes that were associated with radical physico-chemical property changes and were influenced by positive selection. Two such selected non-synonymous amino acid changes were found; one in each of two ecotypes that inhabit the Antarctic pack ice. Both substitutions were associated with changes in local polarity, increased steric constraints and α-helical tendencies that could influence overall metabolic performance, suggesting a functional change.
α-Galactosylceramide-activated Vα14 natural killer T cells mediate protection against murine malaria
Gonzalez-Aseguinolaza, Gloria; de Oliveira, Camila; Tomaska, Margaret; Hong, Seokmann; Bruna-Romero, Oscar; Nakayama, Toshinori; Taniguchi, Masaru; Bendelac, Albert; Van Kaer, Luc; Koezuka, Yasuhiko; Tsuji, Moriya
2000-01-01
Natural killer T (NKT) cells are a unique population of lymphocytes that coexpress a semiinvariant T cell and natural killer cell receptors, which are particularly abundant in the liver. To investigate the possible effect of these cells on the development of the liver stages of malaria parasites, a glycolipid, α-galactosylceramide (α-GalCer), known to selectively activate Vα14 NKT cells in the context of CD1d molecules, was administered to sporozoite-inoculated mice. The administration of α-GalCer resulted in rapid, strong antimalaria activity, inhibiting the development of the intrahepatocytic stages of the rodent malaria parasites Plasmodium yoelii and Plasmodium berghei. The antimalaria activity mediated by α-GalCer is stage-specific, since the course of blood-stage-induced infection was not inhibited by administration of this glycolipid. Furthermore, it was determined that IFN-γ is essential for the antimalaria activity mediated by the glycolipid. Taken together, our results provide the clear evidence that NKT cells can mediate protection against an intracellular microbial infection. PMID:10900007
Swift, Brenna E.; Williams, Brent A.; Kosaka, Yoko; Wang, Xing-Hua; Medin, Jeffrey A.; Viswanathan, Sowmya; Martinez-Lopez, Joaquin; Keating, Armand
2012-01-01
Background Novel therapies capable of targeting drug resistant clonogenic MM cells are required for more effective treatment of multiple myeloma. This study investigates the cytotoxicity of natural killer cell lines against bulk and clonogenic multiple myeloma and evaluates the tumor burden after NK cell therapy in a bioluminescent xenograft mouse model. Design and Methods The cytotoxicity of natural killer cell lines was evaluated against bulk multiple myeloma cell lines using chromium release and flow cytometry cytotoxicity assays. Selected activating receptors on natural killer cells were blocked to determine their role in multiple myeloma recognition. Growth inhibition of clonogenic multiple myeloma cells was assessed in a methylcellulose clonogenic assay in combination with secondary replating to evaluate the self-renewal of residual progenitors after natural killer cell treatment. A bioluminescent mouse model was developed using the human U266 cell line transduced to express green fluorescent protein and luciferase (U266eGFPluc) to monitor disease progression in vivo and assess bone marrow engraftment after intravenous NK-92 cell therapy. Results Three multiple myeloma cell lines were sensitive to NK-92 and KHYG-1 cytotoxicity mediated by NKp30, NKp46, NKG2D and DNAM-1 activating receptors. NK-92 and KHYG-1 demonstrated 2- to 3-fold greater inhibition of clonogenic multiple myeloma growth, compared with killing of the bulk tumor population. In addition, the residual colonies after treatment formed significantly fewer colonies compared to the control in a secondary replating for a cumulative clonogenic inhibition of 89–99% at the 20:1 effector to target ratio. Multiple myeloma tumor burden was reduced by NK-92 in a xenograft mouse model as measured by bioluminescence imaging and reduction in bone marrow engraftment of U266eGFPluc cells by flow cytometry. Conclusions This study demonstrates that NK-92 and KHYG-1 are capable of killing clonogenic and bulk multiple myeloma cells. In addition, multiple myeloma tumor burden in a xenograft mouse model was reduced by intravenous NK-92 cell therapy. Since multiple myeloma colony frequency correlates with survival, our observations have important clinical implications and suggest that clinical studies of NK cell lines to treat MM are warranted. PMID:22271890
Petrov, R V; Saidov, M Z; Koval'chuk, L V; Sorokin, A M; Kaganov, B S
1984-04-01
The activity of natural killers was examined in peripheral blood of healthy subjects and patients with chronic hepatitis and disseminated sclerosis. An attempt was made to correct natural killer activity by human leukocyte interferon in vitro. To assess the activity of natural killers, use was made of the method of serial dilutions. An optimal effector/target ratio was employed in experiments. The patients with chronic hepatitis and disseminated sclerosis demonstrated a reduction in the activity of natural killers whatever the effector/target ratio. The action of interferon in vitro is specific immunomodulatory in nature. Administration of interferon in a dose of 250 Units/ml raises the magnitude of the cytotoxic index in healthy donors and in patients with chronic hepatitis and disseminated sclerosis, making the shape of the killer activity curve approach that of normal. Such an approach can be used for preliminary assessment of the sensitivity of natural killers to interferon in viral diseases of man. The potentialities and efficacy of interferon in clinical medicine are discussed.
Bai, Yan; Zheng, Jin-e; Wang, Nan; Cai, He-hua; Zhai, Li-na; Wu, Yao-hui; Wang, Fang; Jin, Run-ming; Zhou, Dong-feng
2015-10-01
The efficiency of dendritic cell-activated and cytokine-induced killer cell (DC-CIK) therapy on children with acute myeloid leukemia (AML) after chemotherapy was investigated. Mononuclear cells were collected from children achieving complete remission after chemotherapy, cultured in vitro and transfused back into the same patient. Interleukin-2 (IL-2) was injected subcutaneously every other day 10 times at the dose of 1 × 10(6) units. Peripheral blood lymphocyte subsets and minimal residual disease (MRD) were detected by flow cytometry. Function of bone marrow was monitored by methods of morphology, immunology, cytogenetics and molecular biology. The side effects were also observed during the treatment. The average follow-up period for all the 22 patients was 71 months and relapse occurred in two AML patients (9.1%). The percentage of CD3(+)/CD8(+) cells in peripheral blood of 15 patients at the 3rd month after DC-CIK treatment (36.73% ± 12.51%) was dramatically higher than that before treatment (29.20% ± 8.34%, P < 0.05). The MRD rate was >0.1% in 5 patients before the treatment, and became lower than 0.1% 3 months after the treatment. During the transfusion of DC-CIK, side effects including fever, chills and hives appeared in 7 out of 22 (31.82%) cases but disappeared quickly after symptomatic treatments. There were no changes in electrocardiography and liver-renal functions after the treatment. MRD in children with AML can be eliminated by DC-CIK therapy which is safe and has fewer side effects.
Su, Hai-bin; Li, Han-wei; Zhao, Hong-lan; Shi, Ming; Zhang, Bing; Tang, Zi-rong; Lei, Zhou-yun; Wang, Hui-fen; Wang, Fu-sheng
2007-03-01
To observe the therapeutic effect of autologous cytokine-induced killer cells (CIK) on HBV DNA positive patients with liver cirrhosis. HBV DNA positive 33 patients with cirrhosis were treated with CIK. Before and after cultured in vitro and post-treatment, CD3+, CD3+CD4+, CD3+CD8+, CD3+CD56+ cells, mDC and pDC were detected by flow cytometry. The indexes of virus and liver function were compared between pre- and post-treatment. CD3+, CD3+CD8+ cells and CD3+CD56+ cells were higher after cultured in vitro and after transfused back than those before culture (91.5 +/- 10.3, 74.4 +/- 9.9 vs. 67.9 +/- 12.8; 60.9 +/- 15.5, 37.3 +/- 15.1 vs. 27.9 +/- 10.9; 18.4 +/- 11.7, 14.5 +/- 7.5 vs. 10.6 +/- 7.1). The percentages of mDC and pDC also increased after-treatment vs. pre-treatment (0.54 +/- 0.18 vs. 0.70 +/- 0.29; 0.26 +/- 0.13 vs. 0.41 +/- 0.25). HBV DNA became undetectable in 12 patients and decrease exceeded 100 times in 4 patients after treatment. HBeAg became undetectable in 10 of 14 patients who were HBeAg positive pretreatment patients, among them 2 patients had HBeAb sero conversion. The liver function was improved after treatment. All patients tolerated the treatment. CIK treatment can increase immune effector cells and has some antiviral effect and is safe.
NASA Astrophysics Data System (ADS)
Wülfing, Christoph; Purtic, Bozidar; Klem, Jennifer; Schatzle, John D.
2003-06-01
Cytolytic killing is a major effector mechanism in the elimination of virally infected and tumor cells. The innate cytolytic effectors, natural killer (NK) cells, and the adaptive effectors, cytotoxic T cells (CTL), despite differential immune recognition, both use the same lytic mechanism, cytolytic granule release. Using live cell video fluorescence microscopy in various primary cell models of NK cell and CTL killing, we show here that on tight target cell contact, a majority of the NK cells established cytoskeletal polarity required for effective lytic function slowly or incompletely. In contrast, CTLs established cytoskeletal polarity rapidly. In addition, NK cell killing was uniquely sensitive to minor interference with cytoskeletal dynamics. We propose that the stepwise NK cell cytoskeletal polarization constitutes a series of checkpoints in NK cell killing. In addition, the use of more deliberate progression to effector function to compensate for inferior immune recognition specificity provides a mechanistic explanation for how the same effector function can be used in the different functional contexts of the innate and adaptive immune response.
RUNX3 is oncogenic in natural killer/T-cell lymphoma and is transcriptionally regulated by MYC
Selvarajan, V; Osato, M; Nah, G S S; Yan, J; Chung, T-H; Voon, D C-C; Ito, Y; Ham, M F; Salto-Tellez, M; Shimizu, N; Choo, S-N; Fan, S; Chng, W-J; Ng, S-B
2017-01-01
RUNX3, runt-domain transcription factor, is a master regulator of gene expression in major developmental pathways. It acts as a tumor suppressor in many cancers but is oncogenic in certain tumors. We observed upregulation of RUNX3 mRNA and protein expression in nasal-type extranodal natural killer (NK)/T-cell lymphoma (NKTL) patient samples and NKTL cell lines compared to normal NK cells. RUNX3 silenced NKTL cells showed increased apoptosis and reduced cell proliferation. Potential binding sites for MYC were identified in the RUNX3 enhancer region. Chromatin immunoprecipitation–quantitative PCR revealed binding activity between MYC and RUNX3. Co-transfection of the MYC expression vector with RUNX3 enhancer reporter plasmid resulted in activation of RUNX3 enhancer indicating that MYC positively regulates RUNX3 transcription in NKTL cell lines. Treatment with a small-molecule MYC inhibitor (JQ1) caused significant downregulation of MYC and RUNX3, leading to apoptosis in NKTL cells. The growth inhibition resulting from depletion of MYC by JQ1 was rescued by ectopic MYC expression. In summary, our study identified RUNX3 overexpression in NKTL with functional oncogenic properties. We further delineate that MYC may be an important upstream driver of RUNX3 upregulation and since MYC is upregulated in NKTL, further study on the employment of MYC inhibition as a therapeutic strategy is warranted. PMID:28119527
Wang, J.; Cao, X.; Zhao, J.; Zhao, H.; Wei, J.; Li, Q.; Qi, X.; Yang, Z.; Wang, L.; Zhang, H.; Bai, L.; Wu, Z.; Zhao, L.; Hong, Z.
2017-01-01
Summary Dendritic cells (DCs) play critical roles in initiating and regulating innate immunity as well as adaptive immune responses. However, the role of conventional dendritic cells (cDCs) in concanavalin A (ConA)‐induced fulminant hepatitis is unknown. In this study, we demonstrated that depletion of cDCs using either CD11c‐diphtheria toxin receptor transgenic mice (DTR Tg) mice or anti‐CD11c antibody reduced the severity of liver injury significantly, indicating a detrimental role of cDCs in ConA‐induced hepatitis. We elucidated further the pathological role of cDCs as being the critical source of interleukin (IL)‐12, which induced the secretion of interferon (IFN)‐γ by natural killer (NK) T cells. Reconstitution of cDCs‐depleted mice with IL‐12 restored ConA‐induced hepatitis significantly. Furthermore, we determined that NK T cells were the target of DC‐derived IL‐12, and NK T cells contributed to liver inflammation and injury through production of IFN‐γ. In summary, our study demonstrated a novel function of cDCs in mediating ConA‐induced hepatitis through regulating IFN‐γ secretion of NK T cells in an IL‐12‐dependent fashion. Targeting cDCs might provide potentially therapeutic applications in treating autoimmune related liver diseases. PMID:27891589
Lapteva, Natalia; Aldrich, Melissa; Weksberg, David; Rollins, Lisa; Goltsova, Tatiana; Chen, Si-Yi; Huang, Xue F.
2014-01-01
Summary Dendritic cells (DCs) are professional antigen (Ag)-presenting cells capable of inducing immune responses to tumor Ags and, therefore, play a central role in the induction of antitumor immunity. There is a large amount of evidence, however, about paucity of tumor-associated DCs and that DCs’ immunogenic functions are suppressed in a tumor environment. Here we describe a potent in situ vaccine targeting tumoral DCs in vivo. This vaccine comprised of an oncolytic adenovirus expressing RANTES (regulated upon activation, normally T expressed, and presumably secreted) (Ad-RANTES-E1A), enhanced tumor infiltration, and maturation of Ag-presenting cells in vivo. In this study, we show that intratumoral vaccinations with Ad-RANTES-E1A induced significant primary tumor growth regression and blocked metastasis formation in JC and E.G-7 murine tumor models. This vaccine recruited DCs, macrophages, natural killer cells, and CD8+ T cells to the tumor site, and thus enhanced Ag-specific cytotoxic T lymphocyte responses and natural killer cell responses. DCs purified from the Ad-RANTES-E1A–treated E.G-7 tumors secreted significantly higher levels of interferon-γ and interleukin-12, as compared with control groups and more efficiently enhanced CD8+ T-cell response. This in situ immunization strategy could be a potent antitumor immunotherapy approach for aggressive established tumors. PMID:19238013
Kohei, Naoki; Tanaka, Toshiaki; Tanabe, Kazunari; Masumori, Naoya; Dvorina, Nina; Valujskikh, Anna; Baldwin, William M; Fairchild, Robert L
2016-06-01
While the incidence of antibody-mediated kidney graft rejection has increased, the key cellular and molecular participants underlying this graft injury remain unclear. Rejection of kidney allografts in mice lacking the chemokine receptor CCR5 is dependent on production of donor-specific antibody. Here we determine if cells expressing cytotoxic function contributed to antibody-mediated kidney allograft rejection in these recipients. Wild-type C57BL/6, B6.CCR5(-/-), and B6.CD8(-/-)/CCR5(-/-) mice were transplanted with complete MHC-mismatched A/J kidney grafts, and intragraft inflammatory components were followed to rejection. B6.CCR5(-/-) and B6.CD8(-/-)/CCR5(-/-) recipients rejected kidney allografts by day 35, whereas 65% of allografts in wild-type recipients survived past day 80 post-transplant. Rejected allografts in wild-type C57BL/6, B6.CCR5(-/-), and B6.CD8(-/-)/CCR5(-/-) recipients expressed high levels of VCAM-1 and MMP7 mRNA that was associated with high serum titers of donor-specific antibody. High levels of perforin and granzyme B mRNA expression peaked on day 6 post-transplant in allografts in all recipients, but were absent in isografts. Depletion of natural killer cells in B6.CD8(-/-)/CCR5(-/-) recipients reduced this expression to background levels and promoted the long-term survival of 40% of the kidney allografts. Thus, natural killer cells have a role in increased inflammation during antibody-mediated kidney allograft injury and in rejection of the grafts. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.
Kohei, Naoki; Tanaka, Toshiaki; Tanabe, Kazunari; Masumori, Naoya; Dvorina, Nina; Valujskikh, Anna; Baldwin, William M.; Fairchild, Robert L.
2016-01-01
While the incidence of antibody-mediated kidney graft rejection has increased, the key cellular and molecular participants underlying this graft injury remain unclear. Rejection of kidney allografts in mice lacking the chemokine receptor CCR5 is dependent on production of donor-specific antibody. Here we determine if cells expressing cytotoxic function contributed to antibody-mediated kidney allograft rejection in these recipients. Wild type C57BL/6, B6.CCR5−/− and B6.CD8−/−/CCR5−/− mice were transplanted with complete MHC mismatched A/J kidney grafts and intra-graft inflammatory components were followed to rejection. B6.CCR5−/− and B6.CD8−/−/CCR5−/− recipients rejected kidney allografts by day 35 whereas 65% of allografts in wild type recipients survived past day 80 post-transplant. Rejected allografts in wild-type C57BL/6, B6.CCR5−/− and B6.CD8−/−/CCR5−/− recipients expressed high levels of VCAM-1 and MMP7 mRNA that was associated with high serum titers of donor-specific antibody. High levels of perforin and granzyme B mRNA expression peaked on day 6 post-transplant in allografts in all recipients, but were absent in isografts. Depletion of natural killer cells in B6.CD8−/−/CCR5−/− recipients reduced this expression to background levels and promoted the long-term survival of 40% of the kidney allografts. Thus, natural killer cells have a role in increased inflammation during antibody-mediated kidney allograft injury and in rejection of the grafts. PMID:27165816
Morales-Menchén, Ana; Navarro-García, Federico; Guirao-Abad, José P.; Román, Elvira; Prieto, Daniel; Coman, Ioana V.; Pla, Jesús; Alonso-Monge, Rebeca
2018-01-01
Certain yeasts secrete peptides known as killer toxins or mycocins with a deleterious effect on sensitive yeasts or filamentous fungi, a common phenomenon in environmental species. In a recent work, different Debaryomyces hansenii (Dh) strains isolated from a wide variety of cheeses were identified as producing killer toxins active against Candida albicans and Candida tropicalis. We have analyzed the killer activity of these toxins in C. albicans mutants defective in MAPK signaling pathways and found that the lack of the MAPK Hog1 (but not Cek1 or Mkc1) renders cells hypersensitive to Dh mycocins while mutants lacking other upstream elements of the pathway behave as the wild type strain. Point mutations in the phosphorylation site (T174A-176F) or in the kinase domain (K52R) of HOG1 gene showed that both activities were relevant for the survival of C. albicans to Dh killer toxins. Moreover, Hog1 phosphorylation was also required to sense and adapt to osmotic and oxidative stress while the kinase activity was somehow dispensable. Although the addition of supernatant from the killer toxin- producing D. hansenii 242 strain (Dh-242) induced a slight intracellular increase in Reactive Oxygen Species (ROS), overexpression of cytosolic catalase did not protect C. albicans against this mycocin. This supernatant induced an increase in intracellular glycerol concentration suggesting that this toxin triggers an osmotic stress. We also provide evidence of a correlation between sensitivity to Dh-242 killer toxin and resistance to Congo red, suggesting cell wall specific alterations in sensitive strains. PMID:29774204
Arshad, Laiba; Jantan, Ibrahim; Bukhari, Syed Nasir Abbas; Haque, Md Areeful
2017-01-01
The immune system is complex and pervasive as it functions to prevent or limit infections in the human body. In a healthy organism, the immune system and the redox balance of immune cells maintain homeostasis within the body. The failure to maintain the balance may lead to impaired immune response and either over activity or abnormally low activity of the immune cells resulting in autoimmune or immune deficiency diseases. Compounds containing α,β-unsaturated carbonyl-based moieties are often reactive. The reactivity of these groups is responsible for their diverse pharmacological activities, and the most important and widely studied include the natural compounds curcumin, chalcone, and zerumbone. Numerous studies have revealed the mainly immunosuppressive and anti-inflammatory activities of the aforesaid compounds. This review highlights the specific immunosuppressive effects of these natural α,β-unsaturated carbonyl-based compounds, and their analogs and derivatives on different types of immune cells of the innate (granulocytes, monocytes, macrophages, and dendritic cells) and adaptive (T cells, B cells, and natural killer cells) immune systems. The inhibitory effects of these compounds have been comprehensively studied on neutrophils, monocytes and macrophages but their effects on T cells, B cells, natural killer cells, and dendritic cells have not been well investigated. It is of paramount importance to continue generating experimental data on the mechanisms of action of α,β-unsaturated carbonyl-based compounds on immune cells to provide useful information for ensuing research to discover new immunomodulating agents.
Arshad, Laiba; Jantan, Ibrahim; Bukhari, Syed Nasir Abbas; Haque, Md. Areeful
2017-01-01
The immune system is complex and pervasive as it functions to prevent or limit infections in the human body. In a healthy organism, the immune system and the redox balance of immune cells maintain homeostasis within the body. The failure to maintain the balance may lead to impaired immune response and either over activity or abnormally low activity of the immune cells resulting in autoimmune or immune deficiency diseases. Compounds containing α,β-unsaturated carbonyl-based moieties are often reactive. The reactivity of these groups is responsible for their diverse pharmacological activities, and the most important and widely studied include the natural compounds curcumin, chalcone, and zerumbone. Numerous studies have revealed the mainly immunosuppressive and anti-inflammatory activities of the aforesaid compounds. This review highlights the specific immunosuppressive effects of these natural α,β-unsaturated carbonyl-based compounds, and their analogs and derivatives on different types of immune cells of the innate (granulocytes, monocytes, macrophages, and dendritic cells) and adaptive (T cells, B cells, and natural killer cells) immune systems. The inhibitory effects of these compounds have been comprehensively studied on neutrophils, monocytes and macrophages but their effects on T cells, B cells, natural killer cells, and dendritic cells have not been well investigated. It is of paramount importance to continue generating experimental data on the mechanisms of action of α,β-unsaturated carbonyl-based compounds on immune cells to provide useful information for ensuing research to discover new immunomodulating agents. PMID:28194110
Li, Xiao-Feng; Dai, Dong; Song, Xiu-Yu; Liu, Jian-Jing; Zhu, Lei; Zhu, Xiang; Ma, Wenchao; Xu, Wengui
2017-05-01
Natural T cells [cluster of differentiation (CD) 3 + CD56 + ] and natural killer (NK) cells (CD3 - CD56 + ) are particularly abundant in the human liver and serve an important role in immune responses in the liver. The aim of the present study was to extensively determine the phenotypic and functional characteristics of natural T and NK cells in human hepatocellular carcinoma (HCC). Tumorous and non-tumorous tissue infiltrating lymphocytes (TILs and NILs, respectively) and peripheral blood mononuclear cells (PBMCs) from patients with hepatocellular carcinoma (HCC) were obtained to determine the frequency and phenotype of natural T/NK cells by a multicolor fluorescence activated cell sorting analysis. The abundance of natural T cells and NK cells was decreased in TILs vs. NILs (natural T cells, 6.315±1.002 vs. 17.16±1.804; NK cells, 6.324±1.559 vs. 14.52±2.336, respectively). However such results were not observed in PBMCs from HCC patients vs. that of healthy donors. Notably, a substantial fraction of the natural T cells (21.96±5.283) in TILs acquired forkhead box P3 (FOXP3) expression, and the FOXP3 + natural T cells lost the expression of interferon-γ and perforin. Conversely, being similar to the conventional FOXP3 + regulatory T cells, the FOXP3 + natural T cells assumed a specific phenotype that was characteristic of CD25 + , CD45RO + and cytotoxic T-lymphocyte-associated protein 4 + . Consistent with the phenotypic conversion, the present functional results indicate that FOXP3 expression in natural T cells contributes to the acquisition of a potent immunosuppressive capability. In conclusion, the present study describes a different representation of natural T cells and NK cells in local tumor tissues and in the periphery blood of patients with HCC, and identified a new type of FOXP3-expressing natural T cell spontaneously arising in the TILs of HCC.
2015-10-01
sectioned into 5-micron sections. Three serial sections were mounted onto each slide and stained using hematoxylin and eosin (H&E). Five sets of... serial sections were taken from each lung, 100 µm distance between each set. This spacing allows surveillance of metastatic lesions throughout the lung...functions that promote tumor growth may be altered by DEX treatment. For example, IFN- is associated with effector function of natural killer cells
Predatory behaviour in synthetic protocell communities
NASA Astrophysics Data System (ADS)
Qiao, Yan; Li, Mei; Booth, Richard; Mann, Stephen
2017-02-01
Recent progress in the chemical construction of colloidal objects comprising integrated biomimetic functions is paving the way towards rudimentary forms of artificial cell-like entities (protocells). Although several new types of protocells are currently available, the design of synthetic protocell communities and investigation of their collective behaviour has received little attention. Here we demonstrate an artificial form of predatory behaviour in a community of protease-containing coacervate microdroplets and protein-polymer microcapsules (proteinosomes) that interact via electrostatic binding. The coacervate microdroplets act as killer protocells for the obliteration of the target proteinosome population by protease-induced lysis of the protein-polymer membrane. As a consequence, the proteinosome payload (dextran, single-stranded DNA, platinum nanoparticles) is trafficked into the attached coacervate microdroplets, which are then released as functionally modified killer protocells capable of rekilling. Our results highlight opportunities for the development of interacting artificial protocell communities, and provide a strategy for inducing collective behaviour in soft matter microcompartmentalized systems and synthetic protocell consortia.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ross, P.S.; Swart, R.L. de; Timmerman, H.H.
Complex mixtures of lipophilic contaminants have been shown to affect certain top predators in the aquatic food chain, including seals. A recent demonstration that harbor seals (Phoca vitulina) fed Baltic Sea herring displayed impaired natural killer cell activity and T-lymphocyte function represented the first demonstration of immunotoxicity induced by ambient levels of contaminants in the environment. While these animals had a lower ability to respond to immunizations with inactivated vaccines, specific antibody responses, and in vitro antigen-specific lymphoproliferative responses, obvious constraints limited the ability to extend these results with host resistance tests or an evaluation of thymus and other lymphoidmore » organs. The authors therefore set up a parallel study by exposing pregnant laboratory rats to the same Baltic herring contaminant mixture as received the seals. They then examined immune function parameters and host resistance to virus infection. As in the seals, rat pups of the Baltic group had impaired T-lymphocyte function. In addition, thymus cells and/or their precursors appeared to be targeted, as their numbers and function were reduced in the rats. Following challenge with rat cytomegalovirus in a host resistance study, rat pups in the Baltic group had impaired natural killer cell responses to the virus infection, and lower specific CD8 + (cytotoxic T-lymphocyte) responses following in vitro stimulation. By extrapolation, these results suggest that the impaired immune responses observed in the Baltic group of seals may lead to a less effective defense against virus infections in marine mammals inhabiting polluted coastal waters. Toxicological profiles and results of both the captive seal and laboratory rat experiments tend to implicate the 2,3,7,8-TCDD-like PCB, dioxin and furan congeners in the immunosuppression, and point to a major role for the PCBs.« less
Extending the Belgian eID Technology with Mobile Security Functionality
NASA Astrophysics Data System (ADS)
Lapon, Jorn; Verdegem, Bram; Verhaeghe, Pieter; Naessens, Vincent; de Decker, Bart
The Belgian Electronic Identity Card was introduced in 2002. The card enables Belgian citizens to prove their identity digitally and to sign electronic documents. Today, only a limited number of citizens really use the card in electronic applications. A major reason is the lack of killer functionality and killer applications.
Qiu, Yueqin; Jiang, Zongyong; Hu, Shenglan; Wang, Li; Ma, Xianyong; Yang, Xuefen
2017-11-13
Interleukin (IL)-22-producing Natural Killer (NK) cells protect the gut epithelial cell barrier from pathogens. A strain of probiotics, Lactobacillus plantarum (L. plantarum, LP), was previously found by our laboratory to significantly improve the mucosal barrier integrity and function of the small intestine in pigs. However, it was unclear whether LP benefited the intestinal mucosal barrier via interactions with the intestinal NK cells. The present study, therefore, was focused on the therapeutic effect of NK cells that were stimulated by LP on attenuating enterotoxigenic Escherichia coli (ETEC)-induced the damage to the integrity of the epithelial cell barrier. The results showed that LP can efficiently increase protein levels of the natural cytotoxicity receptor (NCR) family, and the expression levels of IL-22 mRNA and protein in NK cells. Transfer of NK cells stimulated by LP conferred protection against ETEC K88-induced intestinal epithelial barrier damage in NCM460 cells. We found that NK cells stimulated by LP could partially offset the reduction in NCM460 cell monolayers transepithelial electrical resistance (TEER) caused by ETEC K88, and increase ZO-1 and occludin mRNA and protein expressions by ETEC K88-infected NCM460 cells. Furthermore, adding NK cells that were stimulated by LP to ETEC K88-infected NCM460cells, IL-22R1, p-Stat3, and p-Tyk2 expression by NCM460 cells was increased. Mechanistic experiment showed that NK cells stimulated by LP lost the function of maintaining TEER of NCM460 cells challenged with ETEC K88, when polyclonal anti-IL-22 antibody was used to block IL-22 production. Collectively, our results suggested that LP stimulation of NK could enhance IL-22 production, which might be able to provide defense against ETEC-induced damage to the integrity of intestinal epithelial barrier.
Location and cellular stages of NK cell development
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
Development and function of human innate immune cells in a humanized mouse model.
Rongvaux, Anthony; Willinger, Tim; Martinek, Jan; Strowig, Till; Gearty, Sofia V; Teichmann, Lino L; Saito, Yasuyuki; Marches, Florentina; Halene, Stephanie; Palucka, A Karolina; Manz, Markus G; Flavell, Richard A
2014-04-01
Mice repopulated with human hematopoietic cells are a powerful tool for the study of human hematopoiesis and immune function in vivo. However, existing humanized mouse models cannot support development of human innate immune cells, including myeloid cells and natural killer (NK) cells. Here we describe two mouse strains called MITRG and MISTRG, in which human versions of four genes encoding cytokines important for innate immune cell development are knocked into their respective mouse loci. The human cytokines support the development and function of monocytes, macrophages and NK cells derived from human fetal liver or adult CD34(+) progenitor cells injected into the mice. Human macrophages infiltrated a human tumor xenograft in MITRG and MISTRG mice in a manner resembling that observed in tumors obtained from human patients. This humanized mouse model may be used to model the human immune system in scenarios of health and pathology, and may enable evaluation of therapeutic candidates in an in vivo setting relevant to human physiology.
Development and function of human innate immune cells in a humanized mouse model
Rongvaux, Anthony; Willinger, Tim; Martinek, Jan; Strowig, Till; Gearty, Sofia V.; Teichmann, Lino L.; Saito, Yasuyuki; Marches, Florentina; Halene, Stephanie; Palucka, A. Karolina; Manz, Markus G.; Flavell, Richard A.
2014-01-01
Mice repopulated with human hematopoietic cells are a powerful tool for the study of human hematopoiesis and immune function in vivo. However, existing humanized mouse models are unable to support development of human innate immune cells, including myeloid cells and NK cells. Here we describe a mouse strain, called MI(S)TRG, in which human versions of four genes encoding cytokines important for innate immune cell development are knocked in to their respective mouse loci. The human cytokines support the development and function of monocytes/macrophages and natural killer cells derived from human fetal liver or adult CD34+ progenitor cells injected into the mice. Human macrophages infiltrated a human tumor xenograft in MI(S)TRG mice in a manner resembling that observed in tumors obtained from human patients. This humanized mouse model may be used to model the human immune system in scenarios of health and pathology, and may enable evaluation of therapeutic candidates in an in vivo setting relevant to human physiology. PMID:24633240
André, Pascale; Spertini, Olivier; Guia, Sophie; Rihet, Pascal; Dignat-George, Françoise; Brailly, Hervé; Sampol, José; Anderson, Paul J.; Vivier, Eric
2000-01-01
Natural killer (NK) cells are components of the innate immune system that can recognize and kill virally infected cells, tumor cells, and allogeneic cells without prior sensitization. NK cells also elaborate cytokines (e.g., interferon-γ and tumor necrosis factor-α) and chemokines (e.g., macrophage inflammatory protein-1α) that promote the acquisition of antigen-specific immunity. NK cell differentiation is accompanied by the cell surface expression of a mucin-like glycoprotein bearing an NK cell-restricted keratan sulfate-related lactosamine carbohydrate, the PEN5 epitope. Here, we report that PEN5 is a post-translational modification of P-selectin glycoprotein ligand-1 (PSGL-1). The PEN5 epitope creates on PSGL-1 a unique binding site for L-selectin, which is independent of PSGL-1 tyrosine sulfation. On the surface of NK cells, the expression of PEN5 is coordinated with the disappearance of L-selectin and the up-regulation of Killer cell Ig-like Receptors (KIR). These results indicate that NK cell differentiation is accompanied by the acquisition of a unique carbohydrate, PEN5, that can serve as part of a combination code to deliver KIR+ NK cells to specific tissues. PMID:10725346
Transcriptional and post-transcriptional regulation of NK cell development and function
Leong, Jeffrey W.; Wagner, Julia A.; Ireland, Aaron R.; Fehniger, Todd A.
2016-01-01
Natural killer (NK) cells are specialized innate lymphoid cells that survey against viral infections and malignancy. Numerous advances have improved our understanding of the molecular mechanisms that control NK cell development and function over the past decade. These include both studies on the regulatory effects of transcription factors and translational repression via microRNAs. In this review, we summarize our current knowledge of DNA-binding transcription factors that regulate gene expression and thereby orchestrate NK cell development and activation, with an emphasis on recent discoveries. Additionally, we highlight our understanding of how RNA-bindings microRNAs fine tune the NK cell molecular program. We also underscore the large number of open questions in field that are now being addressed using new technological approaches and genetically engineered model organisms. Ultimately, a deeper understanding of the basic molecular biology of NK cells will facilitate new strategies to manipulate NK cells for the treatment of human disease. PMID:26948928
Lee, Soo-Hyeon; Shin, Dong-Jun; Kim, Yoseop; Kim, Cheol-Jung; Lee, Je-Jung; Yoon, Mee Sun; Uong, Tung Nguyen Thanh; Yu, Dohyeon; Jung, Ji-Youn; Cho, Duck; Jung, Bock-Gie; Kim, Sang-Ki; Suh, Guk-Hyun
2018-01-01
Natural killer (NK) cells play a pivotal role in the immune response against infections and malignant transformation, and adopted transfer of NK cells is thought to be a promising therapeutic approach for cancer patients. Previous reports describing the phenotypic features of canine NK cells have produced inconsistent results. Canine NK cells are still defined as non-B and non-T (CD3 - CD21 - ) large granular lymphocytes. However, a few reports have demonstrated that canine NK cells share the phenotypic characteristics of T lymphocytes, and that CD3 + CD5 dim CD21 - lymphocytes are putative canine NK cells. Based on our previous reports, we hypothesized that phenotypic modulation could occur between these two populations during activation. In this study, we investigated the phenotypic and functional differences between CD3 + CD5 dim CD21 - (cytotoxic large granular lymphocytes) and CD3 - CD5 - CD21 - NK lymphocytes before and after culture of peripheral blood mononuclear cells isolated from normal dogs. The results of this study show that CD3 + CD5 dim CD21 - lymphocytes can be differentiated into non-B, non-T NK (CD3 - CD5 - CD21 - TCRαβ - TCRγδ - GranzymeB + ) lymphocytes through phenotypic modulation in response to cytokine stimulation. In vitro studies of purified CD3 + CD5 dim CD21 - cells showed that CD3 - CD5 - CD21 - cells are derived from CD3 + CD5 dim CD21 - cells through phenotypic modulation. CD3 + CD5 dim CD21 - cells share more NK cell functional characteristics compared with CD3 - CD5 - CD21 - cells, including the expression of T-box transcription factors (Eomes, T-bet), the production of granzyme B and interferon-γ, and the expression of NK cell-related molecular receptors such as NKG2D and NKp30. In conclusion, the results of this study suggest that CD3 + CD5 dim CD21 - and CD3 - CD5 - CD21 - cells both contain a subset of putative NK cells, and the difference between the two populations may be due to the degree of maturation.
Mulrooney, Tiernan J.; Posch, Phillip E.; Hurley, Carolyn Katovich
2013-01-01
KIR aid in the regulation of NK cell activity. In this study, the effect of the interaction between the KIR2DS and their adapter, DAP12, was investigated beyond the previously defined signaling function. Flow cytometry analysis showed enhanced KIR2DS surface expression on NKL cells when cotransfected with DAP12. Conversely, KIR2DS4 surface expression on primary cells was decreased when the cells were treated with DAP12-specific siRNA. Treatment of the KIR2DS and DAP12-transfected cells with CHX or BFA repressed KIR2DS surface expression, revealing a role for DAP12 in trafficking newly synthesized KIR to the cell surface. Immunoprecipitation of DAP12 revealed an interaction of DAP12 with an immature isoform of KIR2DS, indicating that the interaction likely initiates within the ER. An internalization assay demonstrated a significant impact of DAP12 on KIR2DS surface stability. Confocal microscopy showed that internalized KIR2DS molecules are recruited to lysosomal compartments independent of DAP12 expression. Our results suggest that in vivo conditions that adversely affect DAP12 expression will indirectly reduce surface expression and stability of KIR2DS. These effects could significantly impact ligand recognition and strength of signaling through KIR2DS molecules. PMID:23715743
Zhang, Yu; Huo, Xia; Cao, Junjun; Yang, Tian; Xu, Long; Xu, Xijin
2016-06-01
Lead (Pb) has been proved to exert immunotoxicity to influence immune homeostasis in humans. To monitor the internal Pb level and evaluate its effect on natural killer (NK) cells and cytokine/chemokine concentrations, we recruited 285 preschool children from Guiyu, one of the largest electronic waste (e-waste) destinations and recycling areas in the world, and known to have high concentrations of Pb in the air, soil, water, sediment and plants. A total of 126 preschool children were selected from Haojiang as a reference group. Results showed that children in Guiyu, the exposed area, had higher blood Pb levels and lower percentages of NK cells than children from the reference area. A significantly negative association was found between the percentage of NK cells and increasing Pb levels. Moreover, children in Guiyu area had higher platelet counts and IL-1β concentrations, and lower levels of IL-2, IL-27, MIP-1α and MIP-1β were observed in the exposed children. These changes might not be conducive to the development and differentiation of NK cells. Taken together, the elevated Pb levels result in the lower percentages of NK cells, but also alter the levels of platelets, IL-1β and IL-27, which might be unconducive to the activity and function of NK cells. Copyright © 2016 Elsevier Ltd. All rights reserved.
Barra, Nicole G; Fan, Isabella Y; Gillen, Jenna B; Chew, Marianne; Marcinko, Katarina; Steinberg, Gregory R; Gibala, Martin J; Ashkar, Ali A
2017-12-01
High intensity interval training (HIIT) boosts natural killer (NK) cell number and activity in normal weight breast cancer patients; however, whether this occurs in obese individuals is not well established. The goal of this study was to determine whether HIIT effectively boosts NK cells as a therapeutic strategy against breast cancer in an obese mouse model and in overweight/obese women. Diet induced female C57Bl/6 obese mice were assigned to undergo HIIT for four weeks or remain sedentary. Female participants were subjected to a six weeks HIIT protocol. HIIT mice acclimatized to treadmill running were subsequently injected with 5 × 10 5 polyoma middle T (MT) breast cancer cells intravenously. NK cell number and activation were monitored using flow cytometry, and tumor burden or lipid content evaluated from histological lung and liver tissues, respectively. In both mice and humans, circulating NK cell number and activation (CD3-NK1.1+CD27+ and CD3-CD56+, respectively) markedly increased immediately after HIIT. HIIT obese mice had reduced lung tumor burden compared to controls following MT challenge, and had diminished hepatic lipid deposition despite minimal body weight loss. Our findings demonstrate that HIIT can benefit obese individuals by enhancing NK cell number and activity, reducing tumor burden, and enhancing metabolic health.
Barra, Nicole G.; Fan, Isabella Y.; Gillen, Jenna B.; Chew, Marianne; Marcinko, Katarina; Steinberg, Gregory R.; Gibala, Martin J.; Ashkar, Ali A.
2017-01-01
High intensity interval training (HIIT) boosts natural killer (NK) cell number and activity in normal weight breast cancer patients; however, whether this occurs in obese individuals is not well established. The goal of this study was to determine whether HIIT effectively boosts NK cells as a therapeutic strategy against breast cancer in an obese mouse model and in overweight/obese women. Diet induced female C57Bl/6 obese mice were assigned to undergo HIIT for four weeks or remain sedentary. Female participants were subjected to a six weeks HIIT protocol. HIIT mice acclimatized to treadmill running were subsequently injected with 5 × 105 polyoma middle T (MT) breast cancer cells intravenously. NK cell number and activation were monitored using flow cytometry, and tumor burden or lipid content evaluated from histological lung and liver tissues, respectively. In both mice and humans, circulating NK cell number and activation (CD3−NK1.1+CD27+ and CD3−CD56+, respectively) markedly increased immediately after HIIT. HIIT obese mice had reduced lung tumor burden compared to controls following MT challenge, and had diminished hepatic lipid deposition despite minimal body weight loss. Our findings demonstrate that HIIT can benefit obese individuals by enhancing NK cell number and activity, reducing tumor burden, and enhancing metabolic health. PMID:29302585
Loftus, Róisín M; Assmann, Nadine; Kedia-Mehta, Nidhi; O'Brien, Katie L; Garcia, Arianne; Gillespie, Conor; Hukelmann, Jens L; Oefner, Peter J; Lamond, Angus I; Gardiner, Clair M; Dettmer, Katja; Cantrell, Doreen A; Sinclair, Linda V; Finlay, David K
2018-06-14
Natural killer (NK) cells are lymphocytes with important anti-tumour functions. Cytokine activation of NK cell glycolysis and oxidative phosphorylation (OXPHOS) are essential for robust NK cell responses. However, the mechanisms leading to this metabolic phenotype are unclear. Here we show that the transcription factor cMyc is essential for IL-2/IL-12-induced metabolic and functional responses in mice. cMyc protein levels are acutely regulated by amino acids; cMyc protein is lost rapidly when glutamine is withdrawn or when system L-amino acid transport is blocked. We identify SLC7A5 as the predominant system L-amino acid transporter in activated NK cells. Unlike other lymphocyte subsets, glutaminolysis and the tricarboxylic acid cycle do not sustain OXPHOS in activated NK cells. Glutamine withdrawal, but not the inhibition of glutaminolysis, results in the loss of cMyc protein, reduced cell growth and impaired NK cell responses. These data identify an essential role for amino acid-controlled cMyc for NK cell metabolism and function.
Evans, William
2017-11-01
Positive cancer patient outcomes, including increased time to recurrent events, have been associated with increased counts and function of natural killer (NK) cells. NK cell counts and function are elevated following acute exercise, and the generally accepted mechanism of increased recruitment suggests that binding of epinephrine releases NK cells from endothelial tissue via decreases in adhesion molecules following. I propose that blood flow-induced shear stress may also play a role in NK cell recruitment from the endothelium. Additionally, shear stress may play a role in improving NK cell function by decreasing oxidative stress. The relationship between shear stress and NK cell count and function can be tested by utilizing exercise and local heating with cuff inflation. If shear stress does play an important role, NK cell count and function will be improved in the non-cuffed exercise group, but not the cuffed limb. This paper will explore the mechanisms potentially explaining exercise-induced improvements in NK cell count and function, and propose a model for investigating these mechanisms. This mechanistic insight could aid in providing a novel, safe, relatively inexpensive, and non-invasive target for immunotherapy in cancer patients. Copyright © 2017. Published by Elsevier Ltd.
Neuroanatomy of the killer whale (Orcinus orca) from magnetic resonance images.
Marino, Lori; Sherwood, Chet C; Delman, Bradley N; Tang, Cheuk Y; Naidich, Thomas P; Hof, Patrick R
2004-12-01
This article presents the first series of MRI-based anatomically labeled sectioned images of the brain of the killer whale (Orcinus orca). Magnetic resonance images of the brain of an adult killer whale were acquired in the coronal and axial planes. The gross morphology of the killer whale brain is comparable in some respects to that of other odontocete brains, including the unusual spatial arrangement of midbrain structures. There are also intriguing differences. Cerebral hemispheres appear extremely convoluted and, in contrast to smaller cetacean species, the killer whale brain possesses an exceptional degree of cortical elaboration in the insular cortex, temporal operculum, and the cortical limbic lobe. The functional and evolutionary implications of these features are discussed. (c) 2004 Wiley-Liss, Inc.
Alpha-Fetoprotein and Hepatocellular Carcinoma Immunity
Wang, Qiaoxia
2018-01-01
Hepatocarcinoma is one of the most prevalent gastroenterological cancers in the world with less effective therapy. As an oncofetal antigen and diagnostic marker for liver cancer, alpha-fetoprotein (AFP) possesses a variety of biological functions. Except for its diagnosis in liver cancer, AFP has become a target for liver cancer immunotherapy. Although the immunogenicity of AFP is weak and it could induce the immune escapes through inhibiting the function of dendritic cells, natural killer cells, and T lymphocytes, AFP has attracted more attention in liver cancer immunotherapy. By in vitro modification, the immunogenicity and immune response of AFP could be enhanced. AFP-modified immune cell vaccine or peptide vaccine has displayed the specific antitumor immunity against AFP-positive tumor cells and laid a better foundation for the immunotherapy of liver cancer.
Classification of lymphoid neoplasms: the microscope as a tool for disease discovery
Harris, Nancy Lee; Stein, Harald; Isaacson, Peter G.
2008-01-01
In the past 50 years, we have witnessed explosive growth in the understanding of normal and neoplastic lymphoid cells. B-cell, T-cell, and natural killer (NK)–cell neoplasms in many respects recapitulate normal stages of lymphoid cell differentiation and function, so that they can be to some extent classified according to the corresponding normal stage. Likewise, the molecular mechanisms involved the pathogenesis of lymphomas and lymphoid leukemias are often based on the physiology of the lymphoid cells, capitalizing on deregulated normal physiology by harnessing the promoters of genes essential for lymphocyte function. The clinical manifestations of lymphomas likewise reflect the normal function of lymphoid cells in vivo. The multiparameter approach to classification adopted by the World Health Organization (WHO) classification has been validated in international studies as being highly reproducible, and enhancing the interpretation of clinical and translational studies. In addition, accurate and precise classification of disease entities facilitates the discovery of the molecular basis of lymphoid neoplasms in the basic science laboratory. PMID:19029456
Tracking the Response of Natural Killer T Cells to a Glycolipid Antigen Using Cd1d Tetramers
Matsuda, Jennifer L.; Naidenko, Olga V.; Gapin, Laurent; Nakayama, Toshinori; Taniguchi, Masaru; Wang, Chyung-Ru; Koezuka, Yasuhiko; Kronenberg, Mitchell
2000-01-01
A major group of natural killer (NK) T cells express an invariant Vα14+ T cell receptor (TCR) specific for the lipoglycan α-galactosylceramide (α-GalCer), which is presented by CD1d. These cells may have an important immune regulatory function, but an understanding of their biology has been hampered by the lack of suitable reagents for tracking them in vivo. Here we show that tetramers of mouse CD1d loaded with α-GalCer are a sensitive and highly specific reagent for identifying Vα14+ NK T cells. Using these tetramers, we find that α-GalCer–specific T lymphocytes are more widely distributed than was previously appreciated, with populations of largely NK1.1− but tetramer-binding T cells present in the lymph nodes and the intestine. Injection of α-GalCer leads to the production of both interferon γ and interleukin 4 by nearly all NK T cells in the liver and the majority of the spleen within 2 h. These cells mostly disappear by 5 h, and they do not reappear after 1 wk. Curiously, tetramer-positive thymocytes do not rapidly synthesize cytokines, nor do they undergo decreases in cell number after lipid antigen stimulation, although they express equivalent TCR levels. In summary, the data presented here demonstrate that α-GalCer–specific NK T cells undergo a unique and highly compartmentalized response to antigenic stimulation. PMID:10974039
NK cell subsets in autoimmune diseases.
Zhang, Cai; Tian, Zhigang
2017-09-01
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. Copyright © 2017. Published by Elsevier Ltd.
The expression of human natural killer cell receptors in early life.
Sundström, Y; Nilsson, C; Lilja, G; Kärre, K; Troye-Blomberg, M; Berg, L
2007-01-01
Natural killer (NK) cells play an important role in tumour immunosurveillance and the early defence against viral infections. Recognition of altered cells (i.e. infected- or tumour-cells) is achieved through a multiple receptor recognition strategy which gives the NK cells inhibitory or activating signals depending on the ligands present on the target cell. NK cells originate from the bone marrow where they develop and proliferate. However, further maturation processes and homeostasis of NK cells in peripheral blood are not well understood. To determine the proportions of cells and the expression of NK cell receptors, mononuclear cells from children at three time points during early childhood were compared, i.e. cord blood (CB), 2 and 5 years of age. The proportion of NK cells was high in CB, but the interferon-gamma (IFN-gamma) production low compared to later in life. In contrast, the proportion of T cells was low in CB. This may indicate a deviation of the regulatory function of NK cells in CB compared to later in life, implying an importance of innate immunity in early life before the adaptive immune system matures. Additionally, we found that the proportion of LIR-1(+) NK cells increased with increasing age while CD94(+)NKG2C(-) (NKG2A(+)) NK cells and the level of expression of NKG2D, NKp30 and NKp46 decreased with age. These age related changes in NK cell populations defined by the expression of activating and inhibitory receptors may be the result of pathogen exposure and/or a continuation of the maturation process that begins in the bone marrow.
Licensed human natural killer cells aid dendritic cell maturation via TNFSF14/LIGHT
Holmes, Tim D.; Wilson, Erica B.; Black, Emma V. I.; Benest, Andrew V.; Vaz, Candida; Tan, Betty; Tanavde, Vivek M.; Cook, Graham P.
2014-01-01
Interactions between natural killer (NK) cells and dendritic cells (DCs) aid DC maturation and promote T-cell responses. Here, we have analyzed the response of human NK cells to tumor cells, and we identify a pathway by which NK–DC interactions occur. Gene expression profiling of tumor-responsive NK cells identified the very rapid induction of TNF superfamily member 14 [TNFSF14; also known as homologous to lymphotoxins, exhibits inducible expression, and competes with HSV glycoprotein D for HVEM, a receptor expressed by T lymphocytes (LIGHT)], a cytokine implicated in the enhancement of antitumor responses. TNFSF14 protein expression was induced by three primary mechanisms of NK cell activation, namely, via the engagement of CD16, by the synergistic activity of multiple target cell-sensing NK-cell activation receptors, and by the cytokines IL-2 and IL-15. For antitumor responses, TNFSF14 was preferentially produced by the licensed NK-cell population, defined by the expression of inhibitory receptors specific for self-MHC class I molecules. In contrast, IL-2 and IL-15 treatment induced TNFSF14 production by both licensed and unlicensed NK cells, reflecting the ability of proinflammatory conditions to override the licensing mechanism. Importantly, both tumor- and cytokine-activated NK cells induced DC maturation in a TNFSF14-dependent manner. The coupling of TNFSF14 production to tumor-sensing NK-cell activation receptors links the tumor immune surveillance function of NK cells to DC maturation and adaptive immunity. Furthermore, regulation by NK cell licensing helps to safeguard against TNFSF14 production in response to healthy tissues. PMID:25512551
Person, Rachel J.; Whalen, Margaret M.
2010-01-01
Natural Killer (NK) cells are a major immune defense mechanism against cancer development and viral infection. The butyltins (BTs), tributyltin (TBT) and dibutyltin (DBT) have been widely used in industrial and other applications and significantly contaminate the environment. Both TBT and DBT have been detected in human blood. These compounds inhibit the lytic and binding function of human NK cells and thus could increase the incidence of cancer and viral infections. Butyltin (BT)-induced loss of NK function is accompanied by activation of mitogen activated protein kinases (MAPKs) and decreases in expression of cell-surface and cytolytic proteins. MAPKs activate components of the transcription regulator AP-1 and activate the transcription regulator Elk-1. Based on the fact that BTs activate MAPKs and alter protein expression, the current study examined the effect of BT exposures on the levels and phosphorylation states of the components of AP-1 and the phosphorylation state of Elk-1. Exposure to 300 nM TBT for 10 min increased the phosphorylation of c-Jun in NK cells. 1 h exposures to 300 nM and 200 nM TBT increased the phosphorylation and overall level of c-Jun. During a 300 nM treatment with TBT for 1 h the binding activity of AP-1 was significantly decreased. There were no significant alterations of AP-1 components or of Elk-1 with DBT exposures. Thus, it appears that TBT-induced alterations on phosphorylation, total levels and binding activity of c-Jun might contribute to, but are not fully responsible for, TBT-induced alterations of NK protein expression. PMID:20370538
Person, Rachel J; Whalen, Margaret M
2010-06-01
Natural killer (NK) cells are a major immune defense mechanism against cancer development and viral infection. The butyltins (BTs), tributyltin (TBT) and dibutyltin (DBT), have been widely used in industrial and other applications and significantly contaminate the environment. Both TBT and DBT have been detected in human blood. These compounds inhibit the lytic and binding function of human NK cells and thus could increase the incidence of cancer and viral infections. Butyltin (BT)-induced loss of NK function is accompanied by activation of mitogen activated protein kinases (MAPKs) and decreases in expression of cell-surface and cytolytic proteins. MAPKs activate components of the transcription regulator AP-1 and activate the transcription regulator Elk-1. Based on the fact that BTs activate MAPKs and alter protein expression, the current study examined the effect of BT exposures on the levels and phosphorylation states of the components of AP-1 and the phosphorylation state of Elk-1. Exposure to 300 nM TBT for 10 min increased the phosphorylation of c-Jun in NK cells. One hour exposures to 300 nM and 200 nM TBT increased the phosphorylation and overall level of c-Jun. During a 300 nM treatment with TBT for 1 h the binding activity of AP-1 was significantly decreased. There were no significant alterations of AP-1 components or of Elk-1 with DBT exposures. Thus, it appears that TBT-induced alterations on phosphorylation, total levels, and binding activity of c-Jun might contribute to, but are not fully responsible for, TBT-induced alterations of NK protein expression.
Preethy, Senthilkumar; Dedeepiya, Vidyasagar Devaprasad; Senthilkumar, Rajappa; Rajmohan, Mathaiyan; Karthick, Ramalingam; Terunuma, Hiroshi; Abraham, Samuel J K
2017-07-04
Immune cell-based therapies are emerging as a promising tool to tackle malignancies, both solid tumors and selected hematological tumors. Vast experiences in literature have documented their safety and added survival benefits when such cell-based therapies are combined with the existing treatment options. Numerous methodologies of processing and in vitro expansion protocols of immune cells, such as the dendritic cells, natural killer (NK) cells, NKT cells, αβ T cells, so-called activated T lymphocytes, γδ T cells, cytotoxic T lymphocytes, and lymphokine-activated killer cells, have been reported for use in cell-based therapies. Among this handful of immune cells of significance, the NK cells stand apart from the rest for not only their direct cytotoxic ability against cancer cells but also their added advantage, which includes their capability of (i) action through both innate and adaptive immune mechanism, (ii) tackling viruses too, giving benefits in conditions where viral infections culminate in cancer, and (iii) destroying cancer stem cells, thereby preventing resistance to chemotherapy and radiotherapy. This review thoroughly analyses the sources of such NK cells, methods for expansion, and the future potentials of taking the in vitro expanded allogeneic NK cells with good cytotoxic ability as a drug for treating cancer and/or viral infection and even as a prophylactic tool for prevention of cancer after initial remission.
McIlvried, Lisa A; Cruz, J Agustin; Borghesi, Lisa A; Gold, Michael S
2017-01-01
Aim of investigation Due to compelling evidence in support of links between sex, stress, sympathetic post-ganglionic innervation, dural immune cells, and migraine, our aim was to characterize the impacts of these factors on the type and proportion of immune cells in the dura. Methods Dural immune cells were obtained from naïve or stressed adult male and female Sprague Dawley rats for flow cytometry. Rats with surgical denervation of sympathetic post-ganglionic neurons of the dura were also studied. Results Immune cells comprise ∼17% of all cells in the dura. These included: macrophages/granulocytes ("Macs"; 63.2% of immune cells), dendritic cells (0.88%), T-cells (4.51%), natural killer T-cells (0.51%), natural killer cells (3.08%), and B-cells (20.0%). There were significantly more Macs and fewer B- and natural killer T-cells in the dura of females compared with males. Macs and dendritic cells were significantly increased by stress in males, but not females. In contrast, T-cells were significantly increased in females with a 24-hour delay following stress. Lastly, Macs, dendritic cells, and T-cells were significantly higher in sympathectomized-naïve males, but not females. Conclusions It may not only be possible, but necessary to use different strategies for the most effective treatment of migraine in men and women.
Soluble NKG2D ligands: prevalence, release, and functional impact.
Salih, Helmut Rainer; Holdenrieder, Stefan; Steinle, Alexander
2008-05-01
Natural Killer (NK) cells are capable to recognize and eliminate malignant cells. Anti-tumor responses of NK cells are promoted by the tumor-associated expression of cell stress-inducible ligands of the activating NK receptor NKG2D. Current evidence suggests that established tumors subvert NKG2D-mediated tumor immunosurveillance by releasing NKG2D ligands (NKG2DL). Release of NKG2DL has been observed in a broad variety of human tumor entities and is thought to interfere with NKG2D-mediated tumor immunity in several ways. Further, levels of soluble NKG2DL (sNKG2DL) were also found to be elevated under various non-malignant conditions, although the functional implications remain largely unclear. Here we review and discuss the available data on the prevalence, release, functional impact, and potential clinical value of sNKG2DL.
Ebbo, Mikael; Gérard, Laurence; Carpentier, Sabrina; Vély, Frédéric; Cypowyj, Sophie; Farnarier, Catherine; Vince, Nicolas; Malphettes, Marion; Fieschi, Claire; Oksenhendler, Eric; Schleinitz, Nicolas; Vivier, Eric
2016-04-01
Natural Killer (NK) cells have been shown to exert antiviral and antitumoural activities. Nevertheless most available data are derived from mouse models and functions of these cells in human remain unclear. To evaluate the impact of low circulating NK cell counts and to provide some clues to the role of NK cells in natural conditions, we studied a large cohort of patients with common variable immunodeficiency (CVID) included in a multicenter cohort of patients with primary hypogammaglobulinaemia. Patients were classified into three groups on the basis of their NK cell counts: severe and mild NK cell lymphopenia (<50 and 50-99×10(6)/L respectively), and normal NK cell counts (>100×10(6)/L). Clinical events were analyzed and compared between these three groups of patients. During study period, 457 CVID patients were included: 99 (21.7%) with severe NK cell lymphopenia, 118 (25.8%) with mild NK cell lymphopenia and 240 (52.5%) with normal NK cell counts. Non-infectious complications (57% vs. 36% and 35%), and, particularly, granulomatous complications (25.3% vs. 13.6% and 8.8%), were more frequent in patients with severe NK cell lymphopenia than in other groups. Invasive infections (68.7% vs. 60.2% and 48.8%), including bacteraemia (22.2% vs. 5.9% and 8.3%) and infectious pneumonia (63.6% vs. 59.3% and 44.2%), were also more frequent in this population. However, no difference was observed for viral infections and neoplasms. Low circulating NK cell counts are associated with more severe phenotypes of CVID, which may indicate a protective role of these immune cells against severe bacterial infections and other complications and non-redundant immune functions when the adaptive immune response is not optimal. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
Positive selection on the killer whale mitogenome
Foote, Andrew D.; Morin, Phillip A.; Durban, John W.; Pitman, Robert L.; Wade, Paul; Willerslev, Eske; Gilbert, M. Thomas P.; da Fonseca, Rute R.
2011-01-01
Mitochondria produce up to 95 per cent of the eukaryotic cell's energy. The coding genes of the mitochondrial DNA may therefore evolve under selection owing to metabolic requirements. The killer whale, Orcinus orca, is polymorphic, has a global distribution and occupies a range of ecological niches. It is therefore a suitable organism for testing this hypothesis. We compared a global dataset of the complete mitochondrial genomes of 139 individuals for amino acid changes that were associated with radical physico-chemical property changes and were influenced by positive selection. Two such selected non-synonymous amino acid changes were found; one in each of two ecotypes that inhabit the Antarctic pack ice. Both substitutions were associated with changes in local polarity, increased steric constraints and α-helical tendencies that could influence overall metabolic performance, suggesting a functional change. PMID:20810427
Elsaid, Ahmed F; Shaheen, Magda; Ghoneum, Mamdooh
2018-03-01
Aging is associated with a decline in natural killer (NK) and natural killer T (NKT) cell function that may contribute to increased susceptibility to malignancy and infection. A preliminary investigation was conducted examining the hypothesis that arabinoxylan rice bran (Biobran/MGN-3), a denatured hemicellulose with known immunomodulatory activity, could counteract this decline in NK/NKT cell activity in geriatrics. A total of 12 healthy geriatric subjects of both sexes and over 56 years old, participated in a randomized, double-blind, placebo-controlled clinical trial. A total of six subjects served as control and six subjects ingested Biobran/MGN-3 (500 mg/day) for 30 days. The effect of Biobran/MGN-3 supplementation on NK/NKT cell activity was assessed using the degranulation assay. All study subjects were monitored for the development of any inadvertent side effects. In addition, the pharmacological effects of Biobran/MGN-3 on blood cell components and liver and kidney functions were also assessed. Results demonstrated that Biobran/MGN-3 had no effect on the total percentage of NK cells, however it enhanced the cytotoxic activity of induced NK cell expression of cluster of differentiation 107a, when compared with baseline values and with the placebo group (P<0.05). Furthermore, there were no side effects observed, indicating that Biobran/MGN-3 supplementation was safe at the utilized dosage and for the duration of administration. Various additional beneficial effects were observed, including improved mean corpuscular volume and reduced hepatic aspartate aminotransferase enzyme levels, which suggested improved liver function. It was concluded that Biobran/MGN-3 induces a significant increase in NK activity which may increase resistance to viral infections and cancers in the geriatric population. However, additional clinical trials should be conducted in the future to verify these findings.
Expression of killer inhibitory receptors on cytotoxic cells from HIV-1-infected individuals
Galiani, M D; Aguado, E; Tarazona, R; Romero, P; Molina, I; Santamaria, M; Solana, R; PeñA, J
1999-01-01
Dysfunction of cytotoxic activity of T and natural killer (NK) lymphocytes is a main immunological feature in patients with AIDS, but its basis are not well understood. It has been recently described that T and NK cell-mediated cytotoxicity can be regulated by HLA killer inhibitory receptors (KIR). In this work, we have determined on cytotoxic T cells and NK cells from HIV-1-infected individuals the expression of the following KIR molecules: p58, p70, and ILT2 (immunoglobulin-like family KIR) as well as CD94 and NKG2A (C-lectin-type family KIR). With some exceptions, no significant changes were found on the expression of immunoglobulin-like KIR in either CD8+ or CD56+ cells. Interestingly, the percentages of CD8+ and CD56+ cells expressing CD94 were significantly increased in these individuals. We also show that, in vitro, IL-10 up-regulates CD94 expression on CD8+ and CD56+ cells obtained from normal individuals, suggesting that the augmented expression observed in HIV-infected individuals could be related to the high levels of IL-10 previously described in HIV-1-infected individuals. PMID:10193420
Hercend, T; Griffin, J D; Bensussan, A; Schmidt, R E; Edson, M A; Brennan, A; Murray, C; Daley, J F; Schlossman, S F; Ritz, J
1985-01-01
The initial characterization of two monoclonal antibodies directed at antigens selectively expressed on large granular lymphocytes (LGL) is reported in the present paper. These two reagents, anti-natural killer (NK) H1A and anti-NKH2, were obtained following immunization of mouse spleen cells with a cloned human NK cell line termed JT3. In fresh human peripheral blood, both anti-NKH1A and anti-NKH2 selectively reacted with cells that appeared morphologically as large granular lymphocytes. However, complement lysis studies and two color fluorescence analysis demonstrated that some LGL express both antigens and other cells express only NKH1A or NKH2. Functional analysis of these subsets indicated that the population of NKH1A+ cells contains the entire pool of NK active lymphocytes, whereas expression of NKH2 antigen appeared to delineate a unique subpopulation of LGL which, in a resting state, display a low degree of spontaneous cytotoxicity. Expression of NKH1A and NKH2 was also investigated using a series of nine well characterized human NK clones. All NK clones were found to be NKH1A+ and four out of nine also expressed NKH2. These results strongly supported the view that NKH1A is a "pan-NK" associated antigen, and indicated that at least a fraction of cloned NKH2 + LGL are strongly cytotoxic. Anti-NKH1A was shown to have the same specificity as the previously described N901 antibody and was found here to precipitate a 200,000-220,000-mol wt molecule in SDS-polyacrylamide gel electrophoresis (PAGE) analysis. Anti-NKH2 was specific for a structure that migrates at 60,000 mol wt in SDS-PAGE analysis under reducing conditions. Two color immunofluorescence analysis of NKH1A, NKH2, and other NK-associated antigens (Leu7 and B73.1) demonstrated variable degrees of coexpression of these antigens, which confirmed that NKH1A and NKH2 define distinct cell surface structures. Anti-NKH1A and anti-NKH2 appear to be useful reagents for characterizing LGL present in human peripheral blood and for identifying functionally relevant subsets within this heterogeneous population of cytotoxic lymphocytes. Images PMID:3884668
Crystal structure of the human natural killer cell inhibitory receptor KIR2DL1-HLA-Cw4 complex.
Fan, Q R; Long, E O; Wiley, D C
2001-05-01
Inhibitory natural killer (NK) cell receptors down-regulate the cytotoxicity of NK cells upon recognition of specific class I major histocompatibility complex (MHC) molecules on target cells. We report here the crystal structure of the inhibitory human killer cell immunoglobulin-like receptor 2DL1 (KIR2DL1) bound to its class I MHC ligand, HLA-Cw4. The KIR2DL1-HLA-Cw4 interface exhibits charge and shape complementarity. Specificity is mediated by a pocket in KIR2DL1 that hosts the Lys80 residue of HLA-Cw4. Many residues conserved in HLA-C and in KIR2DL receptors make different interactions in KIR2DL1-HLA-Cw4 and in a previously reported KIR2DL2-HLA-Cw3 complex. A dimeric aggregate of KIR-HLA-C complexes was observed in one KIR2DL1-HLA-Cw4 crystal. Most of the amino acids that differ between human and chimpanzee KIRs with HLA-C specificities form solvent-accessible clusters outside the KIR-HLA interface, which suggests undiscovered interactions by KIRs.
Terrén, Iñigo; Mikelez, Idoia; Odriozola, Irati; Gredilla, Andrea; González, Javier; Orrantia, Ane; Vitallé, Joana; Zenarruzabeitia, Olatz; Borrego, Francisco
2018-01-01
A brief in vitro stimulation of natural killer (NK) cells with interleukin (IL)-12, IL-15, and IL-18 endow them a memory-like behavior, characterized by higher effector responses when they are restimulated after a resting period of time. These preactivated NK cells, also known as cytokine-induced memory-like (CIML) NK cells, have several properties that make them a promising tool in cancer immunotherapy. In the present study, we have described the effect that different combinations of IL-12, IL-15, and IL-18 have on the generation of human CIML NK cells. Our data points to a major contribution of IL-15 to CIML NK cell-mediated cytotoxicity against target cells. However, the synergistic effect of the three cytokines grant them the best polyfunctional profile, that is, cells that simultaneously degranulate (CD107a) and produce multiple cytokines and chemokines such as interferon γ, tumor necrosis factor α, and C-C motif chemokine ligand 3. We have also analyzed the involvement of each cytokine and their combinations in the expression of homing receptors CXCR4 and CD62L, as well as the expression of CD25 and IL-2-induced proliferation. Furthermore, we have tested the effects of the Jak1/2 inhibitor ruxolitinib in the generation of CIML NK cells. We found that ruxolitinib-treated CIML NK cells expressed lower levels of CD25 than non-treated CIML NK cells, but exhibited similar proliferation in response to IL-2. In addition, we have also found that ruxolitinib-treated NK cells displayed reduced effector functions after the preactivation, which can be recovered after a 4 days expansion phase in the presence of low doses of IL-2. Altogether, our results describe the impact that each cytokine and the Jak1/2 pathway have in the phenotype, IL-2-induced proliferation, and effector functions of human CIML NK cells.
Self and viral peptides can initiate lysis by autologous natural killer cells.
Mandelboim, O; Wilson, S B; Valés-Gómez, M; Reyburn, H T; Strominger, J L
1997-04-29
Natural killer (NK) cells are inhibited by specific allotypes of class I major histocompatibility complex ligands recognized by polymorphic inhibitory receptors (e.g., NKIR1 and NKIR2). NK1- and NK2-specific clones recognize two groups of HLA-C allotypes that are distinguished by a dimorphism at residue 80 in the alpha1 helix (alphaLys-80 and alphaAsn-80, respectively). "Empty" HLA-Cw7 expressed in peptide transporter-deficient cells and HLA-Cw7 loaded with several peptides each functioned as inhibitory ligands for NK2 lines and clones. However, loading of HLA-Cw7 with two other peptides derived from glutamic acid decarboxylase or coxsackie virus (each of which has been associated with autoimmune diabetes mellitus) abrogated this inhibitory recognition. Both peptides contained Lys at P8 of the epitope. Substitution of P8 with Ala or two other basic amino acids, His and Arg, resulted in peptides that were inhibitory, as were peptides with P8 Val, Glu, or Asn. The manner in which a Lys at P8 might affect recognition is discussed, together with a hypothesis for a novel mechanism by which an autoimmune disease might be initiated.
Panthong, Sumalee; Itharat, Arunporn
2014-08-01
Immune system is the most important system ofhuman body. Thaifolk doctors have used some medicinal plants as an adaptogenic drug or immunomodulatory agent. Piper chaba Hunter, Piper sarmentosum Roxb. and Piper interruptum Opiz. are used by folk doctors to activate immune response in cancer patients. To investigate the effect on natural killer cell activity and on lymphocyte proliferation activity of water extract of P chaba Hunter P. sarmentosum Roxb. and P interruptum Opiz. MATERIAL ANDMETHOD: Plant materials were extracted by decoction method. All extracts were testedfor an immunomodulatory effect using PBMCs from twelve healthy donors by chromium release assay. Lymphocyte proliferation was also determined by 3H-thymidine uptake assay. The degree of activation was expressed as the stimulation index. The water extract of P chaba Hunter significantly increased lymphocyte proliferation at concentrations ofl ng/ml, 10 ng/ml, 1 μg/ml, 5 μg/ml, 10 μg/ml and 100 μg/ml. P sarmentosum Roxb., and P interruptum Opiz. extracts at those concentrations significantly stimulated lymphocyteproliferation. P sarmentosum Roxb. extractsignificantly increased natural killer (NK) cell activity at a concentration of 100 μg/ml but P chaba Hunter and P interruptum Opiz. extracts did not significantly stimulate natural killer cell activity. P chaba Hunter, P interruptum Opiz. andP sarmentosum Roxb. have an immunomodulatory effect especially for P sarmentosum Roxb. extract which can activate both lymphocyte proliferation and NK cell activity.
Ultrastructural and Functional Effects of Lipopolysaccharide and Interleukin-2 on Human NK Cells
1988-01-01
Leu-lla antibody was Fixation in 1% glut 1% paraf Incubation with stained by HRP using the ABC method via a bio - in ice gold-linked tinylated anti...iilnAd rcsofrCa~Arsloaiti.A.Mro graji~howaweakataintig fr th enzye actvityNn h cl iRfaoo ~u1a el.1.ilvngl cain fa mllprioi(arw nfi.l~X)ofte niecl soin ol... Riccardi C, Santoni A, Stadler BM, Tarameill D, In: Immunobiology of Natural Killer Cells, Vol. 1, Timonen T, Varesio L (1980) Immunoregulation in- Lotzova E
1990-12-20
and infectious mononucleosis , as well as outbreaks of herpes simplex (Ishigami, 1919; Hinkle and Plummer, 1952; McClelland, Alexander, and Marks, 1982...Evans, A., and Neiderman, J., (1979). Psychosocial risk factors in the development of infectious mononucleosis . Psychosomatic Medicine, 41, 445-466...34Stress, Coping, and Infectious Illness: Persistently Low Natural Killer Cell Activity as a Host Ri-k Fa.ctor" 2. PERSONAL AUTHOR(S) Sandra M. Lev
On the communicative significance of whistles in wild killer whales (Orcinus orca)
NASA Astrophysics Data System (ADS)
Thomsen, Frank; Franck, Dierk; Ford, John
2002-08-01
Killer whales (Orcinus orca) use pulsed calls and whistles in underwater communication. Unlike pulsed calls, whistles have received little study and thus their function is poorly known. In this study, whistle activities of groups of individually known killer whales were compared quantitatively across behavioural categories. Acoustic recordings and simultaneous behavioural observations were made of northern resident killer whales off Vancouver Island in 1996 and 1997. Whistles were produced at greater rates than discrete calls during close-range behavioural activities than during long-range activities. They were the predominant sound-type recorded during socializing. The number of whistles per animal per minute was significantly higher during close-range behavioural activities than during long-range activities. Evidently, whistles play an important role in the close-range acoustic communication in northern resident killer whales.
On the communicative significance of whistles in wild killer whales (Orcinus orca).
Thomsen, Frank; Franck, Dierk; Ford, John K B
2002-09-01
Killer whales (Orcinus orca) use pulsed calls and whistles in underwater communication. Unlike pulsed calls, whistles have received little study and thus their function is poorly known. In this study, whistle activities of groups of individually known killer whales were compared quantitatively across behavioural categories. Acoustic recordings and simultaneous behavioural observations were made of northern resident killer whales off Vancouver Island in 1996 and 1997. Whistles were produced at greater rates than discrete calls during close-range behavioural activities than during long-range activities. They were the predominant sound-type recorded during socializing. The number of whistles per animal per minute was significantly higher during close-range behavioural activities than during long-range activities. Evidently, whistles play an important role in the close-range acoustic communication in northern resident killer whales.
Jeong, Won-Il; Park, Ogyi; Suh, Yang-Gun; Byun, Jin-Seok; Park, So-Young; Choi, Earl; Kim, Ja-Kyung; Ko, Hyojin; Wang, Hua; Miller, Andrew M.; Gao, Bin
2011-01-01
Activation of innate immunity (natural killer cell/interferon-γ: NK cell/IFN-γ) has been shown to play an important role in anti-viral and anti-tumor defenses as well as anti-fibrogenesis. However, little is known about the regulation of innate immunity during chronic liver injury. Here, we compared the functions of NK cells in early and advanced liver fibrosis induced by a 2-week or a 10 week-carbon tetrachloride (CCl4) challenge, respectively. Injection of poly I:C or IFN-γ induced NK cell activation and NK cell killing of hepatic stellate cells (HSCs) in the 2-week CCl4 model. Such activation was diminished in the 10-week CCl4 model. Consistent with these findings, the inhibitory effect of poly I:C and IFN-γ on liver fibrosis was markedly reduced in the 10-week vs. the 2-week CCl4 model. In vitro co-culture experiments demonstrated that 4-day cultured (early-activated) HSCs induce NK cell activation via an NKG2D-retinoic acid-induced early gene 1 (RAE1)-dependent mechanism. Such activation was reduced when co-cultured with 8-day cultured (intermediately-activated) HSCs due to the production of transforming growth factor-β (TGF-β) by HSCs. Moreover, early-activated HSCs were sensitive, while intermediately-activated HSCs were resistant to IFN-γ mediated inhibition of cell proliferation, likely due to elevated expression of suppressor of cytokine signaling 1 (SOCS1). Disruption of the SOCS1 gene restored the IFN-γ inhibition of cell proliferation in intermediately-activated HSCs. Production of retinol metabolites by HSCs contributed to SOCS1 induction and subsequently inhibited IFN-γ signaling and functioning, while production of TGF-β by HSCs inhibited NK cell function and cytotoxicity against HSCs. Conclusion The anti-fibrogenic effects of NK cell/IFN-γ are suppressed during advanced liver injury, which is likely due to the increased production of TGF-β and expression of SOCS1 in intermediately-activated HSCs. PMID:21480338
Shenouda, Mira M; Gillgrass, Amy; Nham, Tina; Hogg, Richard; Lee, Amanda J; Chew, Marianne V; Shafaei, Mahsa; Aarts, Craig; Lee, Dean A; Hassell, John; Bane, Anita; Dhesy-Thind, Sukhbinder; Ashkar, Ali A
2017-07-01
Natural killer (NK) cells play a critical role in cancer immunosurveillance. Recent developments in NK cell ex-vivo expansion makes it possible to generate millions of activated NK cells from a small volume of peripheral blood. We tested the functionality of ex vivo expanded NK cells in vitro against breast cancer cell lines and in vivo using a xenograft mouse model. The study aim was to assess functionality and phenotype of expanded NK cells from breast cancer patients against breast cancer cell lines and autologous primary tumours. We used a well-established NK cell co-culture system to expand NK cells ex vivo from healthy donors and breast cancer patients and examined their surface marker expression. Moreover, we tested the ability of expanded NK cells to lyse the triple negative breast cancer and HER2-positive breast cancer cell lines MDA-MB-231 and MDA-MB-453, respectively. We also tested their ability to prevent tumour growth in vivo using a xenograft mouse model. Finally, we tested the cytotoxicity of expanded NK cells against autologous and allogeneic primary breast cancer tumours in vitro. After 3 weeks of culture we observed over 1000-fold expansion of NK cells isolated from either breast cancer patients or healthy donors. We also showed that the phenotype of expanded NK cells is comparable between those from healthy donors and cancer patients. Moreover, our results confirm the ability of ex vivo expanded NK cells to lyse tumour cell lines in vitro. While the cell lines examined had differential sensitivity to NK cell killing we found this was correlated with level of major histocompatibility complex (MHC) class I expression. In our in vivo model, NK cells prevented tumour establishment and growth in immunocompromised mice. Finally, we showed that NK cells expanded from the peripheral blood of breast cancer patients show high cytotoxicity against allogeneic and autologous patient-derived tumour cells in vitro. NK cells from breast cancer patients can be expanded similarly to those from healthy donors, have a high cytotoxic ability against breast cancer cell lines and patient-derived tumour cells, and can be compatible with current cancer treatments to restore NK cell function in cancer patients.
Lin, Mao; Liang, Shuzhen; Jiang, Feng; Xu, Jiongyuan; Zhu, Weibing; Qian, Wei; Hu, Yong; Zhou, Zhanchun; Chen, Jibing; Niu, Lizhi; Xu, Kecheng; Lv, Youyong
2017-03-01
Dendritic cells (DCs) and cytokine-induced killer (CIK) cells have both shown activity as immunotherapy in some malignancies. Our aim was to prospective assess the effect of this immunotherapy in patients with stage IV breast cancer. Between Aug 2003 and Dec 2013, we collected 368 patients who met inclusion criteria and divided into immunotherapy group (treatment group: 188 patients) and chemotherapy group (control group: 180 patients). DCs were prepared from the mononuclear cells isolated from patients in the treatment group using IL-2/GM-CSF and were loaded with tumour antigens; CIK cells were prepared by incubating peripheral blood lymphocytes with IL-2, IFN-γ, and CD3 antibodies. After the patients had received low-dose chemotherapy, those in the treatment group also received the DC-CIK therapy, which was repeated four times in a fortnight to form one cycle. At least three cycles of DC-CIK therapy were given. Immune function was measured in treatment group patients' sera. Disease-free survival (DFS) and Overall survival (OS) after the diagnosis of stage IV breast cancer was assessed after a 10-year follow-up. The result demonstrated that immune function is obviously enhanced after DC-CIK therapy. By Cox regression analysis, DC-CIK therapy reduced the risk of disease progression (p<0.01) with an increased OS (p<0.01). After low-dose chemotherapy, active immunization with DC-CIK immunotherapy is a potentially effective approach for the control of tumour growth in stage IV breast cancer patients. Copyright © 2017 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.
Cold Urticaria, Immunodeficiency, and Autoimmunity Related to PLCG2 Deletions
Ombrello, Michael J.; Remmers, Elaine F.; Sun, Guangping; Freeman, Alexandra F.; Datta, Shrimati; Torabi-Parizi, Parizad; Subramanian, Naeha; Bunney, Tom D.; Baxendale, Rhona W.; Martins, Marta S.; Romberg, Neil; Komarow, Hirsh; Aksentijevich, Ivona; Kim, Hun Sik; Ho, Jason; Cruse, Glenn; Jung, Mi-Yeon; Gilfillan, Alasdair M.; Metcalfe, Dean D.; Nelson, Celeste; O'Brien, Michelle; Wisch, Laura; Stone, Kelly; Douek, Daniel C.; Gandhi, Chhavi; Wanderer, Alan A.; Lee, Hane; Nelson, Stanley F.; Shianna, Kevin V.; Cirulli, Elizabeth T.; Goldstein, David B.; Long, Eric O.; Moir, Susan; Meffre, Eric; Holland, Steven M.; Kastner, Daniel L.; Katan, Matilda; Hoffman, Hal M.; Milner, Joshua D.
2012-01-01
Background Mendelian analysis of disorders of immune regulation can provide insight into molecular pathways associated with host defense and immune tolerance. Methods We identified three families with a dominantly inherited complex of cold-induced urticaria, antibody deficiency, and susceptibility to infection and autoimmunity. Immunophenotyping methods included flow cytometry, analysis of serum immunoglobulins and autoantibodies, lymphocyte stimulation, and enzymatic assays. Genetic studies included linkage analysis, targeted Sanger sequencing, and next-generation whole-genome sequencing. Results Cold urticaria occurred in all affected subjects. Other, variable manifestations included atopy, granulomatous rash, autoimmune thyroiditis, the presence of antinuclear antibodies, sinopulmonary infections, and common variable immunodeficiency. Levels of serum IgM and IgA and circulating natural killer cells and class-switched memory B cells were reduced. Linkage analysis showed a 7-Mb candidate interval on chromosome 16q in one family, overlapping by 3.5 Mb a disease-associated haplotype in a smaller family. This interval includes PLCG2, encoding phospholipase Cγ2 (PLCγ2), a signaling molecule expressed in B cells, natural killer cells, and mast cells. Sequencing of complementary DNA revealed heterozygous transcripts lacking exon 19 in two families and lacking exons 20 through 22 in a third family. Genomic sequencing identified three distinct in-frame deletions that cosegregated with disease. These deletions, located within a region encoding an autoinhibitory domain, result in protein products with constitutive phospholipase activity. PLCG2-expressing cells had diminished cellular signaling at 37°C but enhanced signaling at subphysiologic temperatures. Conclusions Genomic deletions in PLCG2 cause gain of PLCγ2 function, leading to signaling abnormalities in multiple leukocyte subsets and a phenotype encompassing both excessive and deficient immune function. (Funded by the National Institutes of Health Intramural Research Programs and others.) PMID:22236196
Natural killer cells in highly exposed hepatitis C-seronegative injecting drug users.
Mina, M M; Cameron, B; Luciani, F; Vollmer-Conna, U; Lloyd, A R
2016-06-01
Injecting drug use remains the major risk factor for hepatitis C (HCV) transmission. A minority of long-term injecting drug users remain seronegative and aviraemic, despite prolonged exposure to HCV - termed highly exposed seronegative subjects. Natural killer (NK) cells have been implicated in this apparent protection. A longitudinal nested, three group case-control series of subjects was selected from a prospective cohort of seronegative injecting drug users who became incident cases (n = 11), remained seronegative (n = 11) or reported transient high-risk behaviour and remained uninfected (n = 11). The groups were matched by age, sex and initial risk behaviour characteristics. Stored peripheral blood mononuclear cells were assayed in multicolour flow cytometry to enumerate natural killer cell subpopulations and to assess functional activity using Toll-like receptor ligands before measurement of activation, cytokine production and natural cytotoxicity receptor expression. Principal components were derived to describe the detailed phenotypic characteristics of the major NK subpopulations (based on CD56 and CD16 co-expression), before logistic regression analysis to identify associations with exposed, seronegative individuals. The CD56(dim) CD16(+) (P = 0.05, OR 6.92) and CD56(dim) CD16(-) (P = 0.05, OR 6.07) principal components differed between exposed, seronegative individuals and pre-infection samples of the other two groups. These included CD56(dim) CD16(+) and CD56(dim) CD16(-) subsets with CD56(dim) CD16(+) IFN-γ and TNF-α on unstimulated cells, and CD56(dim) CD16(-) CD69(+) , CD107a(+) , IFN-γ and TNF-α following TLR stimulation. The cytotoxic CD56(dim) NK subset thus distinguished highly exposed, seronegative subjects, suggesting NK cytotoxicity may contribute to protection from HCV acquisition. Further investigation of the determinants of this association and prospective assessment of protection against HCV infection are warranted. © 2016 John Wiley & Sons Ltd.
Seo, Naohiro
2017-05-01
In addition to the cytokines and cytotoxic granules, exosomes have been known as the intercellular communicator and cytotoxic missile of immune cells for the past decade. It has been well known that mature dendritic cell(DC)-derived exosomes participate in the T cell and natural killer(NK)cell activation, while immature DCs secrete tolerogenic exosomes for regulatory T(Treg)cell generation. Treg cell-derived EVs act as a suppressor against pathogenic type-1 T helper(Th1)cell responses. CD8+ T cells produce tumoricidal exosomes for preventing tumor invasion and metastasis transiently after T cell receptor(TCR)-mediated stimulation. Thus, immune cells produce functional exosomes in the activation state- and/or differentiation stage-dependent manner. In this review, the role of immune cell-derived exosomes will be introduced, focusing mainly on immune reaction against tumor.
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.
Control of epithelial cell function by interleukin-22-producing RORγt+ innate lymphoid cells
Sanos, Stephanie L; Vonarbourg, Cedric; Mortha, Arthur; Diefenbach, Andreas
2011-01-01
It is rapidly emerging that the defence system of innate lymphocytes is more diverse than previously recognized. In addition to natural killer (NK) cells, lymphoid tissue inducer (LTi) cells, and natural helper cells have now been identified. LTi cells are developmentally dependent on the orphan transcription factor RORγt and instruct lymph node development during embryogenesis. More recently, it has become evident, that in addition to their role for lymph organ development, LTi cells are also potent producers of cytokines such as interleukin-22 (IL-22) and IL-17 in adult mice. In addition to LTi cells, another RORγt-dependent innate lymphocyte subset co-expressing RORγt and NK cell receptors (NKRs) has been identified. These NKR+ RORγt+ cells are also potent producers of IL-22 but it is unclear whether they are part of the NK cell or LTi cell lineage. This review will highlight recent progress in understanding development and function of innate IL-22-producing lymphocyte subsets. PMID:21391996
Lee, Woo-Yong; Sanz, Maria-Jesus; Wong, Connie H Y; Hardy, Pierre-Olivier; Salman-Dilgimen, Aydan; Moriarty, Tara J; Chaconas, George; Marques, Adriana; Krawetz, Roman; Mody, Christopher H; Kubes, Paul
2014-09-23
CXCR6-GFP(+) cells, which encompass 70% invariant natural killer T cells (iNKT cells), have been found primarily patrolling inside blood vessels in the liver. Although the iNKT cells fail to interact with live pathogens, they do respond to bacterial glycolipids presented by CD1d on liver macrophage that have caught the microbe. In contrast, in this study using dual laser multichannel spinning-disk intravital microscopy of joints, the CXCR6-GFP, which also made up 60-70% iNKT cells, were not found in the vasculature but rather closely apposed to and surrounding the outside of blood vessels, and to a lesser extent throughout the extravascular space. These iNKT cells also differed in behavior, responding rapidly and directly to joint-homing pathogens like Borrelia burgdorferi, which causes Lyme disease. These iNKT cells interacted with B. burgdorferi at the vessel wall and disrupted dissemination attempts by these microbes into joints. Successful penetrance of B. burgdorferi out of the vasculature and into the joint tissue was met by a lethal attack by extravascular iNKT cells through a granzyme-dependent pathway, an observation also made in vitro for iNKT cells from joint but not liver or spleen. These results suggest a novel, critical extravascular iNKT cell immune surveillance in joints that functions as a cytotoxic barrier and explains a large increase in pathogen burden of B. burgdorferi in the joint of iNKT cell-deficient mice, and perhaps the greater susceptibility of humans to this pathogen because of fewer iNKT cells in human joints.
Liadi, Ivan; Singh, Harjeet; Romain, Gabrielle; Rey-Villamizar, Nicolas; Merouane, Amine; Adolacion, Jay R T.; Kebriaei, Partow; Huls, Helen; Qiu, Peng; Roysam, Badrinath; Cooper, Laurence J.N.; Varadarajan, Navin
2015-01-01
T cells genetically modified to express a CD19-specific chimeric antigen receptor (CAR) for the investigational treatment of B-cell malignancies comprise a heterogeneous population, and their ability to persist and participate in serial killing of tumor cells is a predictor of therapeutic success. We implemented Timelapse Imaging Microscopy In Nanowell Grids (TIMING) to provide direct evidence that CD4+CAR+ T cells (CAR4 cells) can engage in multi-killing via simultaneous conjugation to multiple tumor cells. Comparisons of the CAR4 cells and CD8+CAR+ T cells (CAR8 cells) demonstrate that while CAR4 cells can participate in killing and multi-killing, they do so at slower rates, likely due to the lower Granzyme B content. Significantly, in both sets of T cells, a minor sub-population of individual T cells identified by their high motility, demonstrated efficient killing of single tumor cells. By comparing both the multi-killer and single killer CAR+ T cells it appears that the propensity and kinetics of T-cell apoptosis was modulated by the number of functional conjugations. T cells underwent rapid apoptosis, and at higher frequencies, when conjugated to single tumor cells in isolation and this effect was more pronounced on CAR8 cells. Our results suggest that the ability of CAR+ T cells to participate in multi-killing should be evaluated in the context of their ability to resist activation induced cell death (AICD). We anticipate that TIMING may be utilized to rapidly determine the potency of T-cell populations and may facilitate the design and manufacture of next-generation CAR+ T cells with improved efficacy. PMID:25711538
A Wickerhamomyces anomalus Killer Strain in the Malaria Vector Anopheles stephensi
Valzano, Matteo; Damiani, Claudia; Epis, Sara; Gabrielli, Maria Gabriella; Conti, Stefania; Polonelli, Luciano; Bandi, Claudio; Favia, Guido; Ricci, Irene
2014-01-01
The yeast Wickerhamomyces anomalus has been investigated for several years for its wide biotechnological potential, especially for applications in the food industry. Specifically, the antimicrobial activity of this yeast, associated with the production of Killer Toxins (KTs), has attracted a great deal of attention. The strains of W. anomalus able to produce KTs, called “killer” yeasts, have been shown to be highly competitive in the environment. Different W. anomalus strains have been isolated from diverse habitats and recently even from insects. In the malaria mosquito vector Anopheles stephensi these yeasts have been detected in the midgut and gonads. Here we show that the strain of W. anomalus isolated from An. stephensi, namely WaF17.12, is a killer yeast able to produce a KT in a cell-free medium (in vitro) as well as in the mosquito body (in vivo). We showed a constant production of WaF17.12-KT over time, after stimulation of toxin secretion in yeast cultures and reintroduction of the activated cells into the mosquito through the diet. Furthermore, the antimicrobial activity of WaF17.12-KT has been demonstrated in vitro against sensitive microbes, showing that strain WaF17.12 releases a functional toxin. The mosquito-associated yeast WaF17.12 thus possesses an antimicrobial activity, which makes this yeast worthy of further investigations, in view of its potential as an agent for the symbiotic control of malaria. PMID:24788884
Current Status of Gene Engineering Cell Therapeutics
Saudemont, Aurore; Jespers, Laurent; Clay, Timothy
2018-01-01
Ex vivo manipulations of autologous patient’s cells or gene-engineered cell therapeutics have allowed the development of cell and gene therapy approaches to treat otherwise incurable diseases. These modalities of personalized medicine have already shown great promises including product commercialization for some rare diseases. The transfer of a chimeric antigen receptor or T cell receptor genes into autologous T cells has led to very promising outcomes for some cancers, and particularly for hematological malignancies. In addition, gene-engineered cell therapeutics are also being explored to induce tolerance and regulate inflammation. Here, we review the latest gene-engineered cell therapeutic approaches being currently explored to induce an efficient immune response against cancer cells or viruses by engineering T cells, natural killer cells, gamma delta T cells, or cytokine-induced killer cells and to modulate inflammation using regulatory T cells. PMID:29459866
Hightower, Allen; van Eijk, Anne Maria; Ayisi, John; Otieno, Juliana; Lal, Renu B.; Steketee, Richard; Nahlen, Bernard; ter Kuile, Feiko O.; Slutsker, Laurence; Shi, Ya Ping
2012-01-01
Pregnant women have abundant natural killer (NK) cells in their placenta, and NK cell function is regulated by polymorphisms of killer cell immunoglobulin-like receptors (KIRs). Previous studies report different roles of NK cells in the immune responses to placental malaria (PM) and human immunodeficiency virus (HIV-1) infections. Given these references, the aim of this study was to determine the association between KIR gene content polymorphism and PM infection in pregnant women of known HIV-1 status. Sixteen genes in the KIR family were analyzed in 688 pregnant Kenyan women. Gene content polymorphisms were assessed in relation to PM in HIV-1 negative and HIV-1 positive women, respectively. Results showed that in HIV-1 negative women, the presence of the individual genes KIR2DL1 and KIR2DL3 increased the odds of having PM, and the KIR2DL2/KIR2DL2 homozygotes were associated with protection from PM. However, the reverse relationship was observed in HIV-1 positive women, where the presence of individual KIR2DL3 was associated with protection from PM, and KIR2DL2/KIR2DL2 homozygotes increased the odds for susceptibility to PM. Further analysis of the HIV-1 positive women stratified by CD4 counts showed that this reverse association between KIR genes and PM remained only in the individuals with high CD4 cell counts but not in those with low CD4 cell counts. Collectively, these results suggest that inhibitory KIR2DL2 and KIR2DL3, which are alleles of the same locus, play a role in the inverse effects on PM and PM/HIV co-infection and the effect of KIR genes on PM in HIV positive women is dependent on high CD4 cell counts. In addition, analysis of linkage disequilibrium (LD) of the PM relevant KIR genes showed strong LD in women without PM regardless of their HIV status while LD was broken in those with PM, indicating possible selection pressure by malaria infection on the KIR genes. PMID:22715396
Dahlberg, Carin I. M.; Sarhan, Dhifaf; Chrobok, Michael; Duru, Adil D.; Alici, Evren
2015-01-01
Natural killer (NK) cells were discovered 40 years ago, by their ability to recognize and kill tumor cells without the requirement of prior antigen exposure. Since then, NK cells have been seen as promising agents for cell-based cancer therapies. However, NK cells represent only a minor fraction of the human lymphocyte population. Their skewed phenotype and impaired functionality during cancer progression necessitates the development of clinical protocols to activate and expand to high numbers ex vivo to be able to infuse sufficient numbers of functional NK cells to the cancer patients. Initial NK cell-based clinical trials suggested that NK cell-infusion is safe and feasible with almost no NK cell-related toxicity, including graft-versus-host disease. Complete remission and increased disease-free survival is shown in a small number of patients with hematological malignances. Furthermore, successful adoptive NK cell-based therapies from haploidentical donors have been demonstrated. Disappointingly, only limited anti-tumor effects have been demonstrated following NK cell infusion in patients with solid tumors. While NK cells have great potential in targeting tumor cells, the efficiency of NK cell functions in the tumor microenvironment is yet unclear. The failure of immune surveillance may in part be due to sustained immunological pressure on tumor cells resulting in the development of tumor escape variants that are invisible to the immune system. Alternatively, this could be due to the complex network of immune-suppressive compartments in the tumor microenvironment, including myeloid-derived suppressor cells, tumor-associated macrophages, and regulatory T cells. Although the negative effect of the tumor microenvironment on NK cells can be transiently reverted by ex vivo expansion and long-term activation, the aforementioned NK cell/tumor microenvironment interactions upon reinfusion are not fully elucidated. Within this context, genetic modification of NK cells may provide new possibilities for developing effective cancer immunotherapies by improving NK cell responses and making them less susceptible to the tumor microenvironment. Within this review, we will discuss clinical trials using NK cells with a specific reflection on novel potential strategies, such as genetic modification of NK cells and complementary therapies aimed at improving the clinical outcome of NK cell-based immune therapies. PMID:26648934
Vaccinating for natural killer cell effector functions.
Wagstaffe, Helen R; Mooney, Jason P; Riley, Eleanor M; Goodier, Martin R
2018-01-01
Vaccination has proved to be highly effective in reducing global mortality and eliminating infectious diseases. Building on this success will depend on the development of new and improved vaccines, new methods to determine efficacy and optimum dosing and new or refined adjuvant systems. NK cells are innate lymphoid cells that respond rapidly during primary infection but also have adaptive characteristics enabling them to integrate innate and acquired immune responses. NK cells are activated after vaccination against pathogens including influenza, yellow fever and tuberculosis, and their subsequent maturation, proliferation and effector function is dependent on myeloid accessory cell-derived cytokines such as IL-12, IL-18 and type I interferons. Activation of antigen-presenting cells by live attenuated or whole inactivated vaccines, or by the use of adjuvants, leads to enhanced and sustained NK cell activity, which in turn contributes to T cell recruitment and memory cell formation. This review explores the role of cytokine-activated NK cells as vaccine-induced effector cells and in recall responses and their potential contribution to vaccine and adjuvant development.
Christakou, Athanasia E; Ohlin, Mathias; Önfelt, Björn; Wiklund, Martin
2015-08-07
We demonstrate a simple method for three-dimensional (3D) cell culture controlled by ultrasonic standing waves in a multi-well microplate. The method gently arranges cells in a suspension into a single aggregate in each well of the microplate and, by this, nucleates 3D tissue-like cell growth for culture times between two and seven days. The microplate device is compatible with both high-resolution optical microscopy and maintenance in a standard cell incubator. The result is a scaffold- and coating-free method for 3D cell culture that can be used for controlling the cellular architecture, as well as the cellular and molecular composition of the microenvironment in and around the formed cell structures. We demonstrate the parallel production of one hundred synthetic 3D solid tumors comprising up to thousands of human hepatocellular carcinoma (HCC) HepG2 cells, we characterize the tumor structure by high-resolution optical microscopy, and we monitor the functional behavior of natural killer (NK) cells migrating, docking and interacting with the tumor model during culture. Our results show that the method can be used for determining the collective ability of a given number of NK cells to defeat a solid tumor having a certain size, shape and composition. The ultrasound-based method itself is generic and can meet any demand from applications where it is advantageous to monitor cell culture from production to analysis of 3D tissue or tumor models using microscopy in one single microplate device.
Lim, Jeong-Ae; Oh, Chung-Sik; Yoon, Tae-Gyoon; Lee, Ji Yeon; Lee, Seung-Hyun; Yoo, Young-Bum; Yang, Jung-Hyun; Kim, Seong-Hyop
2018-02-07
To clarify the effect of anaesthetic agents on cancer immunity, we evaluated the effects of propofol and sevoflurane on natural killer (NK) cell, cytotoxic T lymphocyte (CTL) counts and apoptosis rate in breast cancer and immune cells co-cultures from patients who underwent breast cancer surgery. Venous blood samples were collected after inducing anaesthesia and at 1 and 24 h postoperatively in patients who had undergone breast cancer surgery. The patients were allocated randomly to the propofol- or sevoflurane-based anaesthesia groups. We counted and detected apoptosis in cancer cell, NK cell and CTL of patients with breast cancer by co-culture with a breast cancer cell line in both groups. We also evaluated changes in the cytokines tumour necrosis factor-alpha, interleukin (IL)-6 and IL-10 during the perioperative period. Forty-four patients were included in the final analysis. No difference in NK cell count, CTL count or apoptosis rate was detected between the groups. Furthermore, the number of breast cancer cells undergoing apoptosis in the breast cancer cell co-cultures was not different between the groups. No changes in cytokines were detected between the groups. Although basic science studies have suggested the potential benefits of propofol over a volatile agent during cancer surgery, propofol was not superior to sevoflurane, on the aspects of NK and CTL cells counts with apoptosis rate including breast cancer cell, during anaesthesia for breast cancer surgery in a clinical environment. NCT02758249 on February 26, 2016.
Wu, Junjie; Waxman, David J.
2014-01-01
Metronomic cyclophosphamide (CPA) treatment activates robust innate anti-tumor immunity and induces major regression of large, implanted brain tumor xenografts when administered on an intermittent, every 6-day schedule, but not on a daily low-dose or a maximum-tolerated dose CPA schedule. Here, we used an implanted GL261 glioma model to compare five intermittent metronomic CPA schedules to elucidate the kinetics and schedule dependence of innate immune cell recruitment and tumor regression. Tumor-recruited natural killer cells induced by two every 6-day treatment cycles were significantly ablated one day after a third CPA treatment, but largely recovered several days later. Natural killer and other tumor-infiltrating innate immune cells peaked 12 days after the last CPA treatment on the every 6-day schedule, suggesting that drug-free intervals longer than 6 days may show increased efficacy. Metronomic CPA treatments spaced 9 or 12 days apart, or on an alternating 6 and 9 day schedule, induced extensive tumor regression, similar to the 6-day schedule, however, the tumor-infiltrating natural killer cell responses were not sustained, leading to rapid resumption of tumor regrowth after day 24, despite ongoing metronomic CPA treatment. Increasing the CPA dose prolonged the period of tumor regression on the every 9-day schedule, but natural killer cell activation was markedly decreased. Thus, while several intermittent metronomic CPA treatment schedules can activate innate immune cell recruitment leading to major tumor regression, sustained immune and anti-tumor responses are only achieved on the 6-day schedule. However, even with this schedule, some tumors eventually relapse, indicating a need for further improvements in immunogenic metronomic therapies. PMID:25069038
Zhao, Yan-Jie; Jiang, Ni; Song, Qing-Kun; Wu, Jiang-Ping; Song, Yu-Guang; Zhang, Hong-Mei; Chen, Feng; Zhou, Lei; Wang, Xiao-Li; Zhou, Xin-Na; Yang, Hua-Bing; Ren, Jun; Lyerly, Herbert Kim
2015-01-01
There are few choices for treatment of advanced cancer patients who do not respond to or tolerate conventional anti-cancer treatments. Therefore this study aimed to deploy the benefits and clinical efficacy of continuous dendritic cell-cytokine induced killer cell infusions in such patients. A total of 381 infusions (from 67 advanced cases recruited) were included in this study. All patients underwent peripheral blood mononuclear cell apheresis for the following cellular therapy and dendritic cells-cytokine induced killer cells were expanded in vitro. Peripheral blood T lymphocyte subsets were quantified through flow cytometry to address the cellular immunity status. Clinical efficacy and physical activities were evaluated by RECIST criteria and Eastern Cooperative Oncology Group scores respectively. Logistic regression model was used to estimate the association between cellular infusions and clinical benefits. An average of 5.7±2.94x10(9) induced cells were infused each time and patients were exposed to 6 infusions. Cellular immunity was improved in that cytotoxic CD8+CD28+T lymphocytes were increased by 74% and suppressive CD8+CD28-T lymphocytes were elevated by 16% (p<0.05). Continuous infusion of dendritic cells-cytokine induced killer cells was associated with improvement of both patient status and cellular immunity. A median of six infusions were capable of reducing risk of progression by 70% (95%CI 0.10-0.91). Every elevation of one ECOG score corresponded to a 3.90-fold higher progression risk (p<0.05) and 1% increase of CD8+CD28- T cell proportion reflecting a 5% higher risk of progression (p<0.05). In advanced cancer patients, continuous dendritic cell-cytokine induced killer cell infusions are capable of recovering cellular immunity, improving patient status and quality of life in those who are unresponsive to conventional cancer treatment.
Drexler, H G; Matsuo, Y
2000-05-01
Malignancies involving natural killer (NK) cells are rare disorders. The complexity of NK cell-involving disorders has only recently been appreciated. Modern classifications discern immature (precursor) from mature NK cell leukemias-lymphomas. Continuous NK leukemia-lymphoma cell lines represent important model systems to study these neoplasms. While there are a number of putative NK cell lines which are, however, either not characterized, not immortalized, non-malignant, non-NK, or plain false cell lines, six bona fide malignant NK cell lines have been established and are sufficiently well characterized: HANK1, KHYG-1, NK-92, NKL, NK-YS and YT. Except for YT which was derived from a not further defined acute lymphoblastic lymphoma, these cell lines were established from patients with various NK cell malignancies. Five of the six cell lines are constitutively interleukin-2-dependent. Their immunoprofile is remarkably similar: CD1-, CD2+, surface CD3 (but cytoplasmic CD3epsilon+), CD4-, CD5-, CD7+, CD8-, CD16-, CD56+, CD57-, TCRalphabeta-, TCRgammadelta-, negative for B cell and myelomonocytic markers. The immunoglobulin heavy chain and T cell receptor genes are all in germline configuration. All six lines show complex chromosomal alterations, with both numerical and structural aberrations, attesting to their malignant and monoclonal nature. Functionally, these cells which contain azurophilic granules in their cytoplasm are nearly universally positive in NK activity assays. Three of five cell lines are Epstein-Barr virus-positive (type II latency). The composite data on these six cell lines allow for the operational definition of a typical malignant NK cell line profile. NK leukemia-lymphoma cell lines will prove invaluable for studies of normal and malignant NK cell biology.
Senju, Hiroaki; Kumagai, Asuka; Nakamura, Yoichi; Yamaguchi, Hiroyuki; Nakatomi, Katsumi; Fukami, Shota; Shiraishi, Kengo; Harada, Yuka; Nakamura, Mitsuhiro; Okamura, Haruki; Tanaka, Yoshimasa; Mukae, Hiroshi
2018-01-01
When pathogenic stresses are recognized by innate immune cells, inflammasomes are assembled and caspase-1 is activated, resulting in the conversion of pro-IL-18 into mature IL-18. Because natural killer (NK) cells express IL-18 receptors, IL-18 may play roles in immune functions of NK cells. In the present study, we examined the effect of IL-18 on NK cells derived from lung cancer patients and healthy adult volunteers. When peripheral blood NK cells were stimulated with IL-2, the cells formed clusters beginning on day 5-6 and proliferated thereafter, in which the number of NK cells increased by 10-fold in 10 days. When IL-18 was added, cell clusters were observed as early as on day 4 and NK cells proliferated vigorously. On day 10, the expansion rate was 56-fold on average, showing that IL-18 promoted the expansion of NK cells. It was also notable that IL-18 enhanced the expression of CD80, CD86, HLA-DR and HLA-DQ on NK cells, suggesting that IL-18 conferred NK cells an APC-like phenotype. When cellular cytotoxicity was determined, APC-like NK cells efficiently killed tumor cells and anti-tumor activity was augmented by the addition of tumor antigen-specific mAbs. In addition, IFN-γ was produced by APC-like NK cells in response to tumor cells, and the cytokine production was further enhanced by mAbs. Taken together, IL-18 not only promoted the expansion of NK cells, but also changed the phenotype of NK cells. IL-2/IL-18-induced NK cells might, therefore, serve as a bridge between innate immunity and adaptive immunity and be useful for cancer immunotherapy.
Innate lymphoid cells and the MHC.
Robinette, M L; Colonna, M
2016-01-01
Innate lymphoid cells (ILCs) are a new class of immune cells that include natural killer (NK) cells and appear to be the innate counterparts to CD4(+) helper T cells and CD8(+) cytotoxic T cells based on developmental and functional similarities. Like T cells, both NK cells and other ILCs also show connections to the major histocompatibility complex (MHC). In human and mouse, NK cells recognize and respond to classical and nonclassical MHC I molecules as well as structural homologues, whereas mouse ILCs have recently been shown to express MHC II. We describe the history of MHC I recognition by NK cells and discuss emerging roles for MHC II expression by ILC subsets, making comparisons between both mouse and human when possible. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Ferromagnetic nickel silicide nanowires for isolating primary CD4+ T lymphocytes
NASA Astrophysics Data System (ADS)
Kim, Dong-Joo; Seol, Jin-Kyeong; Lee, Mi-Ri; Hyung, Jung-Hwan; Kim, Gil-Sung; Ohgai, Takeshi; Lee, Sang-Kwon
2012-04-01
Direct CD4+ T lymphocytes were separated from whole mouse splenocytes using 1-dimensional ferromagnetic nickel silicide nanowires (NiSi NWs). NiSi NWs were prepared by silver-assisted wet chemical etching of silicon and subsequent deposition and annealing of Ni. This method exhibits a separation efficiency of ˜93.5%, which is comparable to that of the state-of-the-art superparamagnetic bead-based cell capture (˜96.8%). Furthermore, this research shows potential for separation of other lymphocytes, B, natural killer and natural killer T cells, and even rare tumor cells simply by changing the biotin-conjugated antibodies.
Haustein, Maria; Ramer, Robert; Linnebacher, Michael; Manda, Katrin; Hinz, Burkhard
2014-11-15
Cannabinoids have been shown to promote the expression of the intercellular adhesion molecule 1 (ICAM-1) on lung cancer cells as part of their anti-invasive and antimetastatic action. Using lung cancer cell lines (A549, H460) and metastatic cells derived from a lung cancer patient, the present study addressed the impact of cannabinoid-induced ICAM-1 on cancer cell adhesion to lymphokine-activated killer (LAK) cells and LAK cell-mediated cytotoxicity. Cannabidiol (CBD), a non-psychoactive cannabinoid, enhanced the susceptibility of cancer cells to adhere to and subsequently be lysed by LAK cells, with both effects being reversed by a neutralizing ICAM-1 antibody. Increased cancer cell lysis by CBD was likewise abrogated when CBD-induced ICAM-1 expression was blocked by specific siRNA or by antagonists to cannabinoid receptors (CB1, CB2) and to transient receptor potential vanilloid 1. In addition, enhanced killing of CBD-treated cancer cells was reversed by preincubation of LAK cells with an antibody to lymphocyte function associated antigen-1 (LFA-1) suggesting intercellular ICAM-1/LFA-1 crosslink as crucial event within this process. ICAM-1-dependent pro-killing effects were further confirmed for the phytocannabinoid Δ(9)-tetrahydrocannabinol (THC) and R(+)-methanandamide (MA), a hydrolysis-stable endocannabinoid analogue. Finally, each cannabinoid elicited no significant increase of LAK cell-mediated lysis of non-tumor bronchial epithelial cells, BEAS-2B, associated with a far less pronounced (CBD, THC) or absent (MA) ICAM-1 induction as compared to cancer cells. Altogether, our data demonstrate cannabinoid-induced upregulation of ICAM-1 on lung cancer cells to be responsible for increased cancer cell lysis by LAK cells. These findings provide proof for a novel antitumorigenic mechanism of cannabinoids. Copyright © 2014 Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marcet-Palacios, Marcelo; Odemuyiwa, Solomon O.; Coughlin, Jason J.
2008-02-15
Natural killer cells recognize and induce apoptosis in foreign, transformed or virus-infected cells through the release of perforin and granzymes from secretory lysosomes. Clinically, NK-cell mediated killing is a major limitation to successful allo- and xenotransplantation. The molecular mechanisms that regulate the fusion of granzyme B-containing secretory lysosomes to the plasma membrane in activated NK cells, prior to target cell killing, are not fully understood. Using the NK cell line YT-Indy as a model, we have investigated the expression of SNAP REceptors (SNAREs), both target (t-) and vesicular (v-) SNAREs, and their function in granzyme B-mediated target cell killing. Ourmore » data showed that YT-Indy cells express VAMP-7 and SNAP-23, but not VAMP-2. VAMP-7 was associated with granzyme B-containing lysosomal granules. Using VAMP-7 small interfering RNA (siRNA), we successfully knocked down the expression of VAMP-7 protein in YT-Indy to less than 10% of untreated cells in 24 h. VAMP7-deficient YT-Indy cells activated via co-culture with Jurkat cells released <1 ng/mL of granzyme B, compared to 1.5-2.5 {mu}g/mL from controls. Using Jurkat cells as targets, we showed a 7-fold reduction in NK cell-mediated killing by VAMP-7 deficient YT-Indy cells. Our results show that VAMP-7 is a crucial component of granzyme B release and target cell killing in the NK cell line YT-Indy. Thus, targeting VAMP-7 expression specifically with siRNA, following transplantation, may be a viable strategy for preventing NK cell-mediated transplant rejection, in vivo.« less
Growth and apoptosis of human natural killer cell neoplasms: role of interleukin-2/15 signaling.
Yamasaki, Satoshi; Maeda, Motoi; Ohshima, Koichi; Kikuchi, Masahiro; Otsuka, Teruhisa; Harada, Mine
2004-10-01
Interleukin (IL)-15 plays an important role in the survival of human natural killer (NK) cells. We investigated IL-2/15 signaling in NK cell neoplasms from five patients and in five cell lines (NK-92, KHYG-1, SNK-6, HANK1 and MOTN-1) compared to mature peripheral NK cells from 10 healthy subjects. Apoptosis of NK cell lines was prevented by addition of IL-15 in vitro. Blocking IL-2/15Rbeta on IL-2-stimulated NK-92 cells resulted in reduced expression of Bcl-X(L) and phosphorylated Stat5, which paralleled early apoptosis without altering Bcl-2 expression. These data add IL-2/15Rbeta to the list of factors important for the survival of NK cell neoplasms.
Novakova, Lucie; Nevoralova, Zuzana; Novak, Jan
2012-01-01
Invariant natural killer T (iNKT) cells, CD1d restricted T cells, are involved in the immune responses against various infection agents. Here we describe their behavior during reactivation of human herpes simplex virus (HSV). iNKT cells exhibit only discrete changes, which however, reached statistically significant level due to the relatively large patient group. Higher percentage of iNKT cells express NKG2D. iNKT cells down-regulate NKG2A in a subset of patients. Finally, iNKT cells enhance their capacity to produce TNF-α. Our data suggests that iNKT cells are involved in the immune response against HSV and contribute mainly to its early, innate phase. Copyright © 2012 Elsevier Inc. All rights reserved.
Natural killer cells: In health and disease.
Mandal, Arundhati; Viswanathan, Chandra
2015-06-01
Natural killer (NK) cells constitute our bodies' frontline defense system, guarding against tumors and launching attacks against infections. The activities of NK cells are regulated by the interaction of various receptors expressed on their surfaces with cell surface ligands. While the role of NK cells in controlling tumor activity is relatively clear, the fact that they are also linked to various other disease conditions is now being highlighted. Here, we present an overview of the role of NK cells during normal body state as well as under diseased state. We discuss the possible utilization of these powerful cells as immunotherapeutic agents in combating diseases such as asthma, autoimmune diseases, and HIV-AIDS. This review also outlines current challenges in NK cell therapy. Copyright © 2015. Published by Elsevier B.V.
HIV-1 Control by NK Cells via Reduced Interaction between KIR2DL2 and HLA-C∗12:02/C∗14:03.
Lin, Zhansong; Kuroki, Kimiko; Kuse, Nozomi; Sun, Xiaoming; Akahoshi, Tomohiro; Qi, Ying; Chikata, Takayuki; Naruto, Takuya; Koyanagi, Madoka; Murakoshi, Hayato; Gatanaga, Hiroyuki; Oka, Shinichi; Carrington, Mary; Maenaka, Katsumi; Takiguchi, Masafumi
2016-11-22
Natural killer (NK) cells control viral infection in part through the interaction between killer cell immunoglobulin-like receptors (KIRs) and their human leukocyte antigen (HLA) ligands. We investigated 504 anti-retroviral (ART)-free Japanese patients chronically infected with HIV-1 and identified two KIR/HLA combinations, KIR2DL2/HLA-C ∗ 12:02 and KIR2DL2/HLA-C ∗ 14:03, that impact suppression of HIV-1 replication. KIR2DL2 + NK cells suppressed viral replication in HLA-C ∗ 14:03 + or HLA-C ∗ 12:02 + cells to a significantly greater extent than did KIR2DL2 - NK cells in vitro. Functional analysis showed that the binding between HIV-1-derived peptide and HLA-C ∗ 14:03 or HLA-C ∗ 12:02 influenced KIR2DL2 + NK cell activity through reduced expression of the peptide-HLA (pHLA) complex on the cell surface (i.e., reduced KIR2DL2 ligand expression), rather than through reduced binding affinity of KIR2DL2 to the respective pHLA complexes. Thus, KIR2DL2/HLA-C ∗ 12:02 and KIR2DL2/HLA-C ∗ 14:03 compound genotypes have protective effects on control of HIV-1 through a mechanism involving KIR2DL2-mediated NK cell recognition of virus-infected cells, providing additional understanding of NK cells in HIV-1 infection. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.
Boosting Natural Killer Cell-Based Immunotherapy with Anticancer Drugs: a Perspective.
Cifaldi, Loredana; Locatelli, Franco; Marasco, Emiliano; Moretta, Lorenzo; Pistoia, Vito
2017-12-01
Natural killer (NK) cells efficiently recognize and kill tumor cells through several mechanisms including the expression of ligands for NK cell-activating receptors on target cells. Different clinical trials indicate that NK cell-based immunotherapy represents a promising antitumor treatment. However, tumors develop immune-evasion strategies, including downregulation of ligands for NK cell-activating receptors, that can negatively affect antitumor activity of NK cells, which either reside endogenously, or are adoptively transferred. Thus, restoration of the expression of NK cell-activating ligands on tumor cells represents a strategic therapeutic goal. As discussed here, various anticancer drugs can fulfill this task via different mechanisms. We envision that the combination of selected chemotherapeutic agents with NK cell adoptive transfer may represent a novel strategy for cancer immunotherapy. Copyright © 2017 Elsevier Ltd. All rights reserved.
Theoretical immunology, Part 2: Proceedings
DOE Office of Scientific and Technical Information (OSTI.GOV)
Perelson, A.S.
1988-01-01
This document contains 43 papers on current topics in immunology. Topics include cell chemotaxis, killer cells, AIDS, antigen reactivity, t-cells, crosslinking, cell-cell adhesion, immune response, and the regulation of lymphocyte proliferation. (TEM)
Diandong, Hou; Feng, Gu; Zaifu, Liang; Helland, Timothy; Weixin, Fu; Liping, Cai
2016-03-01
Chronic stress can suppress natural killer (NK) cell activity; this may also be related to the effect of stress on the neuroendocrine-immune network. Sea buckthorn (SBT) (Hippophae rhamnoides L.) is a thorny nitrogen fixing deciduous shrub, native to both Europe and Asia. It has been used as a medicinal plant in Tibetan and Mongolian traditional medicines. SBT has multifarious medical properties, including anti-fatigue as well as immunoregulatory effects. This study reports the effects of SBT oil with regard to the cytotoxicity and quantity of NK cells in the blood of a chronic-stress rat model, in addition to its mechanisms on the neuroendocrine-immune network. These results show that SBT oil, given by gavage to rats with chronic stress, could increase the following: body weight, NK cell quantities, and cytotoxicity, as well as the expression of perforin and granzyme B. The results also show that SBT oil in rats with chronic stress could suppress cortisol, ACTH, IL-1β and TNF-α levels, in addition to increasing 5-HT and IFN-γ serum levels. This leads to suggest that SBT oil, in rats with chronic stress, can increase NK cell cytotoxicity by upregulating the expression of perforin and granzyme B, thus causing associated effects of SBT oil on the neuroendocrine-immune network. © The Author(s) 2015.
Diandong, Hou; Feng, Gu; Zaifu, Liang; Helland, Timothy; Weixin, Fu; Liping, Cai
2015-01-01
Chronic stress can suppress natural killer (NK) cell activity; this may also be related to the effect of stress on the neuroendocrine–immune network. Sea buckthorn (SBT) (Hippophae rhamnoides L.) is a thorny nitrogen fixing deciduous shrub, native to both Europe and Asia. It has been used as a medicinal plant in Tibetan and Mongolian traditional medicines. SBT has multifarious medical properties, including anti-fatigue as well as immunoregulatory effects. This study reports the effects of SBT oil with regard to the cytotoxicity and quantity of NK cells in the blood of a chronic-stress rat model, in addition to its mechanisms on the neuroendocrine–immune network. These results show that SBT oil, given by gavage to rats with chronic stress, could increase the following: body weight, NK cell quantities, and cytotoxicity, as well as the expression of perforin and granzyme B. The results also show that SBT oil in rats with chronic stress could suppress cortisol, ACTH, IL-1β and TNF-α levels, in addition to increasing 5-HT and IFN-γ serum levels. This leads to suggest that SBT oil, in rats with chronic stress, can increase NK cell cytotoxicity by upregulating the expression of perforin and granzyme B, thus causing associated effects of SBT oil on the neuroendocrine–immune network. PMID:26684638
Petitdemange, Caroline; Becquart, Pierre; Wauquier, Nadia; Béziat, Vivien; Debré, Patrice; Leroy, Eric M; Vieillard, Vincent
2011-09-01
Chikungunya virus (CHIKV) is a worldwide emerging pathogen. In humans it causes a syndrome characterized by high fever, polyarthritis, and in some cases lethal encephalitis. Growing evidence indicates that the innate immune response plays a role in controlling CHIKV infection. We show here that CHIKV induces major but transient modifications in NK-cell phenotype and function soon after the onset of acute infection. We report a transient clonal expansion of NK cells that coexpress CD94/NKG2C and inhibitory receptors for HLA-C1 alleles and are correlated with the viral load. Functional tests reveal cytolytic capacity driven by NK cells in the absence of exogenous signals and severely impaired IFN-γ production. Collectively these data provide insight into the role of this unique subset of NK cells in controlling CHIKV infection by subset-specific expansion in response to acute infection, followed by a contraction phase after viral clearance.
Natural killer cells regulate T cell immune responses in primary biliary cirrhosis.
Shimoda, Shinji; Hisamoto, Satomi; Harada, Kenichi; Iwasaka, Sho; Chong, Yong; Nakamura, Minoru; Bekki, Yuki; Yoshizumi, Tomoharu; Shirabe, Ken; Ikegami, Toru; Maehara, Yoshihiko; He, Xiao-Song; Gershwin, M Eric; Akashi, Koichi
2015-12-01
The hallmark of primary biliary cirrhosis (PBC) is the presence of autoreactive T- and B-cell responses that target biliary epithelial cells (BECs). Biliary cell cytotoxicity is dependent upon initiation of innate immune responses followed by chronic adaptive, as well as bystander, mechanisms. Critical to these mechanisms are interactions between natural killer (NK) cells and BECs. We have taken advantage of the ability to isolate relatively pure viable preparations of liver-derived NK cells, BECs, and endothelial cells, and studied interactions between NK cells and BECs and focused on the mechanisms that activate autoreactive T cells, their dependence on interferon (IFN)-γ, and expression of BEC major histocompatibility complex (MHC) class I and II molecules. Here we show that at a high NK/BEC ratio, NK cells are cytotoxic for autologous BECs, but are not dependent on autoantigen, yet still activate autoreactive CD4(+) T cells in the presence of antigen presenting cells. In contrast, at a low NK/BEC ratio, BECs are not lysed, but IFN-γ production is induced, which facilitates expression of MHC class I and II molecules on BEC and protects them from lysis upon subsequent exposure to autoreactive NK cells. Furthermore, IFN-γ secreted from NK cells after exposure to autologous BECs is essential for this protective function and enables autoreactive CD4(+) T cells to become cytopathic. NK cell-mediated innate immune responses are likely critical at the initial stage of PBC, but also facilitate and maintain the chronic cytopathic effect of autoantigen-specific T cells, essential for progression of disease. © 2015 by the American Association for the Study of Liver Diseases.
Low-frequency signals produced by Northeast Atlantic killer whales (Orcinus orca).
Samarra, Filipa I P; Deecke, Volker B; Miller, Patrick J O
2016-03-01
Killer whale acoustic behavior has been extensively investigated; however, most studies have focused on pulsed calls and whistles. This study reports the production of low-frequency signals by killer whales at frequencies below 300 Hz. Recordings were made in Iceland and Norway when killer whales were observed feeding on herring and no other marine mammal species were nearby. Low-frequency sounds were identified in Iceland and ranged in duration between 0.14 and 2.77 s and in frequency between 50 and 270 Hz, well below the previously reported lower limit for killer whale tonal sounds of 500 Hz. Low-frequency sounds appeared to be produced close in time to tail slaps, which are indicative of feeding attempts, suggesting that these sounds may be related to a feeding context. However, their precise function is unknown, and they could be the by-product of a non-vocal behavior rather than a vocal signal deliberately produced by the whales. Although killer whales in Norway exhibit similar feeding behavior, this sound has not been detected in recordings from Norway to date. This study suggests that, like other delphinids, killer whales produce low-frequency sounds, but further studies will be required to understand whether similar sounds exist in other killer whale populations.
Heatley, Susan L.; Pietra, Gabriella; Lin, Jie; Widjaja, Jacqueline M. L.; Harpur, Christopher M.; Lester, Sue; Rossjohn, Jamie; Szer, Jeff; Schwarer, Anthony; Bradstock, Kenneth; Bardy, Peter G.; Mingari, Maria Cristina; Moretta, Lorenzo; Sullivan, Lucy C.; Brooks, Andrew G.
2013-01-01
Natural killer (NK) cell recognition of the nonclassical human leukocyte antigen (HLA) molecule HLA-E is dependent on the presentation of a nonamer peptide derived from the leader sequence of other HLA molecules to CD94-NKG2 receptors. However, human cytomegalovirus can manipulate this central innate interaction through the provision of a “mimic” of the HLA-encoded peptide derived from the immunomodulatory glycoprotein UL40. Here, we analyzed UL40 sequences isolated from 32 hematopoietic stem cell transplantation recipients experiencing cytomegalovirus reactivation. The UL40 protein showed a “polymorphic hot spot” within the region that encodes the HLA leader sequence mimic. Although all sequences that were identical to those encoded within HLA-I genes permitted the interaction between HLA-E and CD94-NKG2 receptors, other UL40 polymorphisms reduced the affinity of the interaction between HLA-E and CD94-NKG2 receptors. Furthermore, functional studies using NK cell clones expressing either the inhibitory receptor CD94-NKG2A or the activating receptor CD94-NKG2C identified UL40-encoded peptides that were capable of inhibiting target cell lysis via interaction with CD94-NKG2A, yet had little capacity to activate NK cells through CD94-NKG2C. The data suggest that UL40 polymorphisms may aid evasion of NK cell immunosurveillance by modulating the affinity of the interaction with CD94-NKG2 receptors. PMID:23335510
Heatley, Susan L; Pietra, Gabriella; Lin, Jie; Widjaja, Jacqueline M L; Harpur, Christopher M; Lester, Sue; Rossjohn, Jamie; Szer, Jeff; Schwarer, Anthony; Bradstock, Kenneth; Bardy, Peter G; Mingari, Maria Cristina; Moretta, Lorenzo; Sullivan, Lucy C; Brooks, Andrew G
2013-03-22
Natural killer (NK) cell recognition of the nonclassical human leukocyte antigen (HLA) molecule HLA-E is dependent on the presentation of a nonamer peptide derived from the leader sequence of other HLA molecules to CD94-NKG2 receptors. However, human cytomegalovirus can manipulate this central innate interaction through the provision of a "mimic" of the HLA-encoded peptide derived from the immunomodulatory glycoprotein UL40. Here, we analyzed UL40 sequences isolated from 32 hematopoietic stem cell transplantation recipients experiencing cytomegalovirus reactivation. The UL40 protein showed a "polymorphic hot spot" within the region that encodes the HLA leader sequence mimic. Although all sequences that were identical to those encoded within HLA-I genes permitted the interaction between HLA-E and CD94-NKG2 receptors, other UL40 polymorphisms reduced the affinity of the interaction between HLA-E and CD94-NKG2 receptors. Furthermore, functional studies using NK cell clones expressing either the inhibitory receptor CD94-NKG2A or the activating receptor CD94-NKG2C identified UL40-encoded peptides that were capable of inhibiting target cell lysis via interaction with CD94-NKG2A, yet had little capacity to activate NK cells through CD94-NKG2C. The data suggest that UL40 polymorphisms may aid evasion of NK cell immunosurveillance by modulating the affinity of the interaction with CD94-NKG2 receptors.
Gamliel, Moriya; Anderson, Karen L; Ebstein, Richard P; Yirmiya, Nurit; Mankuta, David
2016-01-01
Killer-cell immunoglobulin-like receptors (KIRs) are a family of cell surface proteins found on natural killer cells, which are components of the innate immune system. KIRs recognize MHC class I proteins, mainly HLA-C and are further divided into two groups: short-tailed 2/3DS activating receptors and long-tailed 2/3DL inhibitory receptors. Based on the Barker Hypothesis, the origins of illness can be traced back to embryonic development in the uterus, and since KIR:HLA interaction figures prominently in the maternal-fetal interface, we investigated whether specific KIR:HLA combinations may be found in autism spectrum disorders (ASD) children compared with their healthy parents. This study enrolled 49 ASD children from different Israeli families, and their healthy parents. Among the parents, a higher frequency of HLA-C2 allotypes was found in the fathers, while its corresponding ligand 2DS1 was found in higher percentage in the maternal group. However, such skewing in KIR:HLA frequencies did not appear in the ASD children. Additionally, analysis of "overall activation" indicated higher activation in maternal than in paternal cohorts.
Borgerding, Andrea; Hasenkamp, Justin; Engelke, Michael; Burkhart, Nina; Trümper, Lorenz; Wienands, Jürgen; Glass, Bertram
2010-03-01
Antibody-dependent cellular cytotoxicity (ADCC) by natural killer (NK) cells is a major effector mechanism of the monoclonal anti-CD20 antibody rituximab in eliminating B-cell lymphomas. Resistance to this treatment occurs, although CD20 antigen is expressed on the tumor cells. A model of ADCC was established by stimulating human bulk NK cells and inhibitory killer immunoglobulin receptor (KIR)-defined NK cells from human leukocyte antigen (HLA)-typed donors. NK-cell activation was triggered via stimulation of the Fc receptor with immunoglobulin G aggregates, rituximab-labeled HLA-defined CD20-positive B-lymphoblast cell lines or CD20-positive B-lymphoma cell lines. The effect of KIR ligation by anti-KIR antibodies and HLA, the HLA expression density and rituximab concentrations on the efficacy of ADCC were analyzed in granzyme B ELISPOT measuring NK-cell activation and fluorescein-activated cell sorting cytotoxicity assay. HLA, but not CD20 expression density correlated with NK-cell activity against rituximab-labeled targets. ADCC was increased or decreased following HLA shielding or KIR activation by anti-KIR antibodies, respectively. Herein we show that rituximab-induced ADCC is attenuated upon ligation of KIR by HLA molecules expressed on human B-lymphoma target cells. Moreover, anti-KIR antibodies do not only block KIR/HLA interactions, but display agonistic effects at the KIR, which has to be considered for therapeutical applications. KIR activation and HLA expression density are critical determinants for the efficacy of rituximab treatment. An explanation for the failure of rituximab treatment may be the protection of the tumor cells from ADCC by inhibiting NK-cell function with their surface HLA. Copyright 2010 ISEH - Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.
Levinson, Ralph D.; Yung, Madeline; Meguro, Akira; Ashouri, Elham; Yu, Fei; Mizuki, Nobuhisa; Ohno, Shigeaki
2016-01-01
Cytotoxic T lymphocytes (CTL) and natural killer (NK) cells are killer lymphocytes that provide defense against viral infections and tumor transformation. Analogous to that of CTL, interactions of killer-cell immunoglobulin-like receptors (KIR) with specific human leukocyte antigen (HLA) class I ligands calibrate NK cell education and response. Gene families encoding KIRs and HLA ligands are located on different chromosomes, and feature variation in the number and type of genes. The independent segregation of KIR and HLA genes results in variable KIR-HLA interactions in individuals, which may impact disease susceptibility. We tested whether KIR-HLA combinations are associated with Vogt-Koyanagi-Harada (VKH) disease, a bilateral granulomatous panuveitis that has strong association with HLA-DR4. We present a case control study of 196 VKH patients and 209 controls from a highly homogeneous native population of Japan. KIR and HLA class I genes were typed using oligonucleotide hybridization method and analyzed using two-tailed Fisher’s exact probabilities. The incidence of Bx-KIR genotypes was decreased in VKH patients (odds ratio [OR] 0.58, P = 0.007), due primarily to a decrease in centromeric B-KIR motif and its associated KIRs 2DS2, 2DL2, 2DS3, and 2DL5B. HLA-B22, implicated in poor immune response, was increased in VKH (OR = 4.25, P = 0.0001). HLA-Bw4, the ligand for KIR3DL1, was decreased in VKH (OR = 0.59, P = 0.01). The KIR-HLA combinations 2DL2+C1/C2 and 3DL1+Bw4, which function in NK education, were also decreased in VKH (OR = 0.49, P = 0.012; OR = 0.59, P = 0.013). Genotypes missing these two inhibitory KIR-HLA combinations in addition to missing activating KIRs 2DS2 and 2DS3 were more common in VKH (OR = 1.90, P = 0.002). These results suggest that synergistic hyporesponsiveness of NK cells (due to poor NK education along with missing of activating KIRs) and CTL (due to HLA-B22 restriction) fail to mount an effective immune response against viral-infection that may trigger VKH pathogenesis in genetically susceptible individuals, such as HLA-DR4 carriers. PMID:27490240
Human HLA-Ev (147) Expression in Transgenic Animals.
Matsuura, R; Maeda, A; Sakai, R; Eguchi, H; Lo, P-C; Hasuwa, H; Ikawa, M; Nakahata, K; Zenitani, M; Yamamichi, T; Umeda, S; Deguchi, K; Okuyama, H; Miyagawa, S
2016-05-01
In our previous study, we reported on the development of substituting S147C for HLA-E as a useful gene tool for xenotransplantation. In this study we exchanged the codon of HLA-Ev (147), checked its function, and established a line of transgenic mice. A new construct, a codon exchanging human HLA-Ev (147) + IRES + human beta 2-microgloblin, was established. The construct was subcloned into pCXN2 (the chick beta-actin promoter and cytomegalovirus enhancer) vector. Natural killer cell- and macrophage-mediated cytotoxicities were performed using the established the pig endothelial cell (PEC) line with the new gene. Transgenic mice with it were next produced using a micro-injection method. The expression of the molecule on PECs was confirmed by the transfection of the plasmid. The established molecules on PECs functioned well in regulating natural killer cell-mediated cytotoxicity and macrophage-mediated cytotoxicity. We have also successfully generated several lines of transgenic mice with this plasmid. The expression of HLA-Ev (147) in each mouse organ was confirmed by assessing the mRNA. The chick beta-actin promoter and cytomegalovirus enhancer resulted in a relatively broad expression of the gene in each organ, and a strong expression in the cases of the heart and lung. A synthetic HLA-Ev (147) gene with a codon usage optimized to a mammalian system represents a critical factor in the development of transgenic animals for xenotransplantation. Copyright © 2016 Elsevier Inc. All rights reserved.
Rana, Krupa; Whalen, Margaret M.
2015-01-01
Up to now, the ability of target cells to activate protein kinase C (PKC) and protein kinase D (PKD) (which is often a downstream target of PKC) has not been examined in natural killer (NK) lymphocytes. Here we examined whether exposure of human NK cells to lysis sensitive tumor cells activated PKC and PKD. The results of these studies show for the first time that activation of PKC and PKD occurs in response to target cell binding to NK cells. Exposure of NK cells to K562 tumor cells for 10 and 30 minutes increased phosphorylation/activation of both PKC and PKD by roughly 2 fold. Butyltins (tributyltin (TBT); dibutyltin (DBT)) and brominated compounds (tetrabromobisphenol A (TBBPA)) are environmental contaminants that are found in human blood. Exposures of NK cells to TBT, DBT or TBBPA decrease NK cell lytic function in part by activating the mitogen activated protein kinases (MAPKs) that are part of the NK lytic pathway. We established that PKC and PKD are part of the lytic pathway upstream of MAPKs and thus we investigated whether DBT, TBT, and TBBPA exposures activated PKC and PKD. TBT activated PKC by 2–3 fold at 10 min at concentrations ranging from 50–300 nM while DBT caused a 1.3 fold activation at 2.5 μM at 10 min. Both TBT and DBT caused an approximately 2 fold increase in phosphorylation/activation of PKC. Exposures to TBBPA caused no statistically significant changes in either PKC or PKD activation. PMID:26228090
Patiño, Pablo J; Caraballo, Domingo I; Szewczyk, Katarzyna; Quintana, Juan C; Bedoya, Lady R; Ramírez, Beatriz E; Jaramillo, Andrés
2017-09-29
Exercise-induced stress induces considerable changes in the immune system. To better understand the mechanisms related to these immune changes during acute and chronic physical stress, we studied the effects of aerobic physical training (APT) on several parameters of the immune system. Previously untrained males (18-25 years of age) were divided into a group that was subjected to 6 months of APT (n=10) and a sedentary control group (n=7). The subjects performed a cardiopulmonary exercise test (CET) at 0, 3, and 6 months of the APT program. B cell (CD19+), T cell (CD4+ and CD8+), and natural killer cell (CD56+) levels, and mitogen-induced T cell proliferation and cytokine production (interleukin-1, interleukin-4, interleukin-12, and interferon-) were evaluated before and at 30 seconds and 24 hours after the CET. There was a significant increase in CD4+ T cells and natural killer cells and a significant reduction in T cell proliferation in both groups 30 seconds after the CET at 3 and 6 months of the APT program. Of note, the trained group showed significantly lower resting T cell proliferation (before and 24 hour after the CET) than the sedentary control group at 3 and 6 months of the APT program. There were no significant differences in cytokine production after the CET between both groups at any time point of the APT program. These data show that APT does not condition against strenuous exercise induced immune changes but significantly modulates T cell proliferative responses.
Glycolipid presentation to natural killer T cells differs in an organ-dependent fashion
NASA Astrophysics Data System (ADS)
Schmieg, John; Yang, Guangli; Franck, Richard W.; van Rooijen, Nico; Tsuji, Moriya
2005-01-01
It has been shown that dendritic cells (DCs) are able to present glycolipids to natural killer (NK) T cells in vivo. However, the essential role of DCs, as well as the role of other cells in glycolipid presentation, is unknown. Here, we show that DCs are the crucial antigen-presenting cells (APCs) for splenic NK T cells, whereas Kupffer cells are the key APCs for hepatic NK T cells. Both cell types stimulate cytokine production by NK T cells within 2 h of glycolipid administration, but only DCs are involved in the systemic, downstream responses to glycolipid administration. More specifically, CD8+ DCs produce IL-12 in response to glycolipid presentation, which stimulates secondary IFN- production by NK cells in different organs. Different APCs participate in glycolipid presentation to NK T cells in vivo but differ in their involvement in the overall glycolipid response. dendritic cell | Kupffer cell
Regulation of NK92-MI cell cytotoxicity by substance P.
Fu, W X; Qin, B; Zhou, A P; Yu, Q Y; Huang, Q J; Liang, Z F
2011-08-01
The neuropeptide substance P (SP) can regulate a number of immunological functions in vitro and in vivo and may regulate natural killer (NK) cell activity. Here, we investigated whether SP has a role in regulating NK92-MI cell function in vitro, and how it influences NK cell activity. We found that SP dose dependently increased the cytotoxicity of NK92-MI cells and had a maximal effect at a concentration of 10(-12) and 10(-10) m. Furthermore, the expression of cytotoxic-associated molecules (perforin, granzyme) and activating receptor NKp46 [a member of natural cytotoxicity receptors (NCRs)] was observed to be upregulated by SP at optimal concentration, at which SP enhanced the cytotoxicity of NK92-MI cells. Neurokinin-1 receptor (NK-1R), a functional receptor of SP, was found on NK92-MI cells, and the observed effects of SP on NK92-MI cells could be more partially blocked by an NK-1R antagonist. Our data suggest that SP induces NK92-MI cell cytotoxicity by directly increasing the expression of cytotoxic granules and upregulates NK92-MI cell receptor-mediated functions indirectly. Thus, SP may regulate NK cell function mainly through NK-1R. © 2011 The Authors. Scandinavian Journal of Immunology © 2011 Blackwell Publishing Ltd.
Wallace, Alison E.; Goulwara, Sonu S.; Whitley, Guy S.; Cartwright, Judith E.
2014-01-01
Decidual natural killer (dNK) cells have been shown to both promote and inhibit trophoblast behavior important for decidual remodeling in pregnancy and have a distinct phenotype compared to peripheral blood NK cells. We investigated whether different levels of oxygen tension, mimicking the physiological conditions of the decidua in early pregnancy, altered cell surface receptor expression and activity of dNK cells and their interactions with trophoblast. dNK cells were isolated from terminated first-trimester pregnancies and cultured in oxygen tensions of 3%, 10%, and 21% for 24 h. Cell surface receptor expression was examined by flow cytometry, and the effects of secreted factors in conditioned medium (CM) on the trophoblast cell line SGHPL-4 were assessed in vitro. SGHPL-4 cells treated with dNK cell CM incubated in oxygen tensions of 10% were significantly more invasive (P < 0.05) and formed endothelial-like networks to a greater extent (P < 0.05) than SGHPL-4 cells treated with dNK cell CM incubated in oxygen tensions of 3% or 21%. After 24 h, a lower percentage of dNK cells expressed CD56 at 21% oxygen (P < 0.05), and an increased percentage of dNK cells expressed NKG2D at 10% oxygen (P < 0.05) compared to other oxygen tensions, with large patient variation. This study demonstrates dNK cell phenotype and secreted factors are modulated by oxygen tension, which induces changes in trophoblast invasion and endovascular-like differentiation. Alterations in dNK cell surface receptor expression and secreted factors at different oxygen tensions may represent regulation of function within the decidua during the first trimester of pregnancy. PMID:25232021
Komatsu, M; Yee, L; Carraway, K L
1999-05-01
Sialomucin complex (SMC) is a large heterodimeric glycoprotein complex composed of a mucin subunit ascites sialoglycoprotein-1 and a transmembrane subunit ascites sialoglycoprotein-2. It is a rat homologue of human mucin gene MUC4 and is abundantly expressed on the cell surface of highly metastatic ascites 13762 rat mammary adenocarcinoma cells. Because of their extended and rigid structures, mucin-type glycoproteins are suggested to have suppressing effects on cell-cell and cell-matrix interactions. During the metastatic process, these effects presumably cause tumor cell detachment from the primary tumor mass and facilitate escape of the tumor cells from immunosurveillance. Analyses of human breast cancer cells in solid tumors and tumor effusions showed that the more aggressive cells in effusions are stained with polyclonal antibodies against SMC more frequently than cells in solid tumors, suggesting a role for MUC4/SMC in tumor progression and metastasis. Previously, we generated recombinant cDNAs for SMC that vary in the number of mucin repeats to study the putative functions of SMC in tumor metastasis. These cDNAs were transfected into human cancer cell lines and tested for the effect of the expression of this gene. Here, using a tetracycline-responsive inducible expression system, we demonstrate that overexpression of SMC masks the surface antigens on target tumor cells and effectively suppresses tumor cell killing by cytotoxic lymphocytes. This effect results from the ability of SMC to block killer cell binding to the tumor cells and is dependent on both overexpression of the mucin and the number of mucin repeats in the expressed SMC. These results provide an explanation for the proposed role of SMC/MUC4 in tumor progression.
A Novel Feeder-free System for Mass Production of Murine Natural Killer Cells In Vitro.
Tang, Patrick Ming-Kuen; Tang, Philip Chiu-Tsun; Chung, Jeff Yat-Fai; Hung, Jessica Shuk Chun; Wang, Qing-Ming; Lian, Guang-Yu; Sheng, Jingyi; Huang, Xiao-Ru; To, Ka-Fai; Lan, Hui-Yao
2018-01-09
Natural killer (NK) cells belong to the innate immune system and are a first-line anti-cancer immune defense; however, they are suppressed in the tumor microenvironment and the underlying mechanism is still largely unknown. The lack of a consistent and reliable source of NK cells limits the research progress of NK cell immunity. Here, we report an in vitro system that can provide high quality and quantity of bone marrow-derived murine NK cells under a feeder-free condition. More importantly, we also demonstrate that siRNA-mediated gene silencing successfully inhibits the E4bp4-dependent NK cell maturation by using this system. Thus, this novel in vitro NK cell differentiating system is a biomaterial solution for immunity research.
Lactic Acid Bacteria from Kefir Increase Cytotoxicity of Natural Killer Cells to Tumor Cells.
Yamane, Takuya; Sakamoto, Tatsuji; Nakagaki, Takenori; Nakano, Yoshihisa
2018-03-27
The Japanese fermented beverage, homemade kefir, contains six lactic acid bacteria: Lactococcus. lactis subsp. Lactis , Lactococcus . lactis subsp. Cremoris , Lactococcus. Lactis subsp. Lactis biovar diacetylactis , Lactobacillus plantarum , Leuconostoc meseuteroides subsp. Cremoris and Lactobacillus casei . In this study, we found that a mixture of the six lactic acid bacteria from kefir increased the cytotoxicity of human natural killer KHYG-1 cells to human chronic myelogenous leukemia K562 cells and colorectal tumor HCT116 cells. Furthermore, levels of mRNA expression and secretion of IFN-γ (interferon gamma) increased in KHYG-1 cells that had been treated with the six lactic acid bacteria mixture from kefir. The results suggest that the six lactic acid bacteria mixture from kefir has strong effects on natural immunity and tumor cell cytotoxicity.
Lactic Acid Bacteria from Kefir Increase Cytotoxicity of Natural Killer Cells to Tumor Cells
Yamane, Takuya; Sakamoto, Tatsuji; Nakagaki, Takenori; Nakano, Yoshihisa
2018-01-01
The Japanese fermented beverage, homemade kefir, contains six lactic acid bacteria: Lactococcus. lactis subsp. Lactis, Lactococcus. lactis subsp. Cremoris, Lactococcus. Lactis subsp. Lactis biovar diacetylactis, Lactobacillus plantarum, Leuconostoc meseuteroides subsp. Cremoris and Lactobacillus casei. In this study, we found that a mixture of the six lactic acid bacteria from kefir increased the cytotoxicity of human natural killer KHYG-1 cells to human chronic myelogenous leukemia K562 cells and colorectal tumor HCT116 cells. Furthermore, levels of mRNA expression and secretion of IFN-γ (interferon gamma) increased in KHYG-1 cells that had been treated with the six lactic acid bacteria mixture from kefir. The results suggest that the six lactic acid bacteria mixture from kefir has strong effects on natural immunity and tumor cell cytotoxicity. PMID:29584690
Liver natural killer cells: subsets and roles in liver immunity
Peng, Hui; Wisse, Eddie; Tian, Zhigang
2016-01-01
The liver represents a frontline immune organ that is constantly exposed to a variety of gut-derived antigens as a result of its unique location and blood supply. With a predominant role in innate immunity, the liver is enriched with various innate immune cells, among which natural killer (NK) cells play important roles in host defense and in maintaining immune balance. Hepatic NK cells were first described as ‘pit cells' in the rat liver in the 1970s. Recent studies of NK cells in mouse and human livers have shown that two distinct NK cell subsets, liver-resident NK cells and conventional NK (cNK) cells, are present in this organ. Here, we review liver NK cell subsets in different species, revisiting rat hepatic pit cells and highlighting recent progress related to resident NK cells in mouse and human livers, and also discuss the dual roles of NK cells in liver immunity. PMID:26639736
Law, Becker M P; Wilkinson, Ray; Wang, Xiangju; Kildey, Katrina; Lindner, Mae; Rist, Melissa J; Beagley, Kenneth; Healy, Helen; Kassianos, Andrew J
2017-07-01
Natural killer (NK) cells are a population of lymphoid cells that play a significant role in mediating innate immune responses. Studies in mice suggest a pathological role for NK cells in models of kidney disease. In this study, we characterized the NK cell subsets present in native kidneys of patients with tubulointerstitial fibrosis, the pathological hallmark of chronic kidney disease. Significantly higher numbers of total NK cells (CD3 - CD56 + ) were detected in renal biopsies with tubulointerstitial fibrosis compared with diseased biopsies without fibrosis and healthy kidney tissue using multi-color flow cytometry. At a subset level, both the CD56 dim NK cell subset and particularly the CD56 bright NK cell subset were elevated in fibrotic kidney tissue. However, only CD56 bright NK cells significantly correlated with the loss of kidney function. Expression of the tissue-retention and -activation molecule CD69 on CD56 bright NK cells was significantly increased in fibrotic biopsy specimens compared with non-fibrotic kidney tissue, indicative of a pathogenic phenotype. Further flow cytometric phenotyping revealed selective co-expression of activating receptor CD335 (NKp46) and differentiation marker CD117 (c-kit) on CD56 bright NK cells. Multi-color immunofluorescent staining of fibrotic kidney tissue localized the accumulation of NK cells within the tubulointerstitium, with CD56 bright NK cells (NKp46 + CD117 + ) identified as the source of pro-inflammatory cytokine interferon-γ within the NK cell compartment. Thus, activated interferon-γ-producing CD56 bright NK cells are positioned to play a key role in the fibrotic process and progression to chronic kidney disease. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.
Verstrepen, B E; Nieuwenhuis, I G; Mooij, P; Bogers, W M; Boonstra, A; Koopman, G
2016-07-01
In humans, CD16 and CD56 are used to identify functionally distinct natural killer (NK) subsets. Due to ubiquitous CD56 expression, this marker cannot be used to distinguish between NK cell subsets in chimpanzees. Therefore, functional analysis of distinct NK subsets during hepatitis C virus (HCV) infection has never been performed in these animals. In the present study an alternative strategy was used to identify four distinct NK subsets on the basis of the expression of CD16 and CD94. The expression of activating and inhibiting surface receptors showed that these subsets resemble human NK subsets. CD107 expression was used to determine degranulation of the different subsets in naive and HCV-infected chimpanzees. In HCV-infected chimpanzees increased spontaneous cytotoxicity was observed in CD94(high/dim) CD16(pos) and CD94(low) CD16(pos) subsets. By contrast, increased natural cytotoxicity receptor (NCR)- mediated degranulation after NKp30 and NKp44 triggering was demonstrated in the CD94(dim) CD16(neg) subset. Our findings suggest that spontaneous and NCR-mediated cytotoxicity are effector functions of distinct NK subsets in HCV-infected chimpanzees. © 2016 British Society for Immunology.
Sahu, Sudhanshu; Li, Rong; Kadeyala, Praveen Kumar; Liu, Shisong; Schachner, Melitta
2018-05-01
Human natural killer-1 (HNK-1) cell antigen is a glycan epitope involved in several neural events, such as neuritogenesis, myelination, synaptic plasticity and regeneration of the nervous system after injury. We have recently identified the small organic compound ursolic acid (UA) as a HNK-1 mimetic with the aim to test its therapeutic potential in the central nervous system. UA, a plant-derived pentacyclic triterpenoid, is well known for its multiple biological functions, including neuroprotective, antioxidant and anti-inflammatory activities. In the present study, we evaluated its functions in a mouse model of spinal cord injury (SCI) and explored the molecular mechanisms underlying its positive effects. Oral administration of UA to mice 1 h after SCI and thereafter once daily for 6 weeks enhanced the regaining of motor functions and axonal regrowth, and decreased astrogliosis. UA administration decreased levels of proinflammatory markers, including interleukin-6 and tumor necrosis factor-α, in the injured spinal cord at the acute phase of inflammation and activated the mitogen-activated protein kinase and phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin pathways in the injured spinal cord. Taken together, these results suggest that UA may be a candidate for treatment of nervous system injuries. Copyright © 2017. Published by Elsevier Inc.
Kashiwagi, T; Kunishima, N; Suzuki, C; Tsuchiya, F; Nikkuni, S; Arata, Y; Morikawa, K
1997-01-15
Several strains of yeasts and fungi produce proteinous substances, termed killer toxins, which kill sensitive strains. The SMK toxin, secreted by the halotolerant yeast Pichia farinosa KK1 strain, uniquely exhibits its maximum killer activity under conditions of acidic pH and high salt concentration. The toxin is composed of two distinct subunits, alpha and beta, which tightly interact with each other under acidic conditions. However, they are easily dissociated under neutral conditions and lose the killer activity. The three-dimensional structure of the SMK toxin will provide a better understanding of the mechanism of toxicity of this protein and the cause of its unique pH-dependent stability. Two crystal structures of the SMK toxin have been determined at 1.8 A resolution in different ionic strength conditions. The two subunits, alpha and beta, are jointly folded into an ellipsoidal, single domain structure belonging to the alpha/beta-sandwich family. The folding topology of the SMK toxin is essentially the same as that of the fungal killer toxin, KP4. This shared topology contains two left-handed split betaalphabeta motifs, which are rare in the other proteins. Many acidic residues are clustered at the bottom of the SMK toxin molecule. Some of the carboxyl sidechains interact with each other through hydrogen bonds. The ionic strength difference induces no evident structural change of the SMK toxin except that, in the high ionic strength crystal, a number of sulfate ions are electrostatically bound near the basic residues which are also locally distributed at the bottom of the toxin molecule. The two killer toxins, SMK and KP4, share a unique folding topology which contains a rare structural motif. This observation may suggest that these toxins are evolutionally and/or functionally related. The pH-dependent stability of the SMK toxin is a result of the intensive interactions between the carboxyl groups. This finding is important for protein engineering, for instance, towards stabilization of the toxin molecule in a broader pH range. The present crystallographic study revealed that the structure of the SMK toxin itself is hardly affected by the ionic strength, implying that a high salt concentration affects the sensitivity of the cell against the toxin.
Kotas, Maya E; Locksley, Richard M
2018-06-19
Innate lymphoid cells (ILCs) are positioned in tissues perinatally, constitutively express receptors responsive to their organ microenvironments, and perform an arsenal of effector functions that overlap those of adaptive CD4 + T cells. Based on knowledge regarding subsets of invariant-like lymphocytes (e.g., natural killer T [NKT] cells, γδ T cells, mucosal-associated invariant T [MAIT] cells, etc.) and fetally derived macrophages, we hypothesize that immune cells established during the perinatal period-including, but not limited to, ILCs-serve intimate roles in tissue that go beyond classical understanding of the immune system in microbial host defense. In this Perspective, we propose mechanisms by which the establishment of ILCs and the tissue lymphoid niche during early development may have consequences much later in life. Although definitive answers require better tools, efforts to achieve deeper understanding of ILC biology across the mammalian lifespan have the potential to lift the veil on the unknown breadth of immune cell functions. Copyright © 2018 Elsevier Inc. All rights reserved.
Mehlomakulu, N N; Prior, K J; Setati, M E; Divol, B
2017-03-01
The control of the wine spoilage yeast Brettanomyces bruxellensis using biological methods such as killer toxins (instead of the traditional chemical methods, e.g. SO 2 ) has been the focus of several studies within the last decade. Our previous research demonstrated that the killer toxins CpKT1 and CpKT2 isolated from the wine yeast Candida pyralidae were active and stable under winemaking conditions. In this study, we report the possible mode of action of CpKT1 on B. bruxellensis cells in red grape juice. Brettanomyces bruxellensis cells were exposed to CpKT1 either directly or through co-inoculation with C. pyralidae. This exposure yielded a temporary or permanent decline of the spoilage yeast population depending on the initial cell concentration. Scanning electron microscopy revealed cell surface abrasion while propidium iodide viability staining showed that CpKT1 caused plasma membrane damage on B. bruxellensis cells. Our data show that the exposure to CpKT1 resulted in increased levels of β-glucan, suggesting a compensatory response of the sensitive cells. The toxin CpKT1 causes cell membrane and cell wall damage in B. bruxellensis. Candida pyralidae shows potential to be used as a biocontrol agent against B. bruxellensis in grape juice/wine. © 2016 The Society for Applied Microbiology.
The heterogeneity of human CD127(+) innate lymphoid cells revealed by single-cell RNA sequencing.
Björklund, Åsa K; Forkel, Marianne; Picelli, Simone; Konya, Viktoria; Theorell, Jakob; Friberg, Danielle; Sandberg, Rickard; Mjösberg, Jenny
2016-04-01
Innate lymphoid cells (ILCs) are increasingly appreciated as important participants in homeostasis and inflammation. Substantial plasticity and heterogeneity among ILC populations have been reported. Here we have delineated the heterogeneity of human ILCs through single-cell RNA sequencing of several hundreds of individual tonsil CD127(+) ILCs and natural killer (NK) cells. Unbiased transcriptional clustering revealed four distinct populations, corresponding to ILC1 cells, ILC2 cells, ILC3 cells and NK cells, with their respective transcriptomes recapitulating known as well as unknown transcriptional profiles. The single-cell resolution additionally divulged three transcriptionally and functionally diverse subpopulations of ILC3 cells. Our systematic comparison of single-cell transcriptional variation within and between ILC populations provides new insight into ILC biology during homeostasis, with additional implications for dysregulation of the immune system.
Ryu, Je Il; Han, Myung Hoon; Cheong, Jin Hwan; Kim, Jae Min; Kim, Choong Hyun
2017-03-01
The therapeutic outcome for those with malignant glioma is poor, even though diverse therapeutic modalities have been developed. Immunotherapy has emerged as a therapeutic approach for malignant gliomas, making it possible to selectively treat tumors while sparing normal tissue. Here, we review clinical trials of adoptive immunotherapy approaches for malignant gliomas. We also describe a clinical trial that examined the efficacy and safety of autologous cytokine-induced killer (CIK) cells along with concomitant chemoradiotherapy for newly diagnosed glioblastoma. These CIK cells identify and kill autologous tumor cells. This review focuses on the use of adoptive immunotherapy for malignant gliomas and reviews the current literature on the concept of antitumor activity mediated by CIK cells.
Streck, R J; Helinski, E H; Ovak, G M; Pauly, J L
1990-09-01
Lymphokine (i.e., interleukin 2; IL-2)-activated killer (LAK) cells derived from normal human blood are known to destroy human tumor target cells. Accordingly, immunotherapy modalities using IL-2, either alone or in combination with LAK cells, have been evaluated for eradicating metastatic cancer. In studies conducted to characterize receptors on LAK cell membrane ultrastructures, we observed that LAK cells kill autologous human monocyte-derived macrophages (M phi). In these experiments, peripheral blood mononuclear cells of a healthy adult donor were cultured to generate LAK cells and autologous non-adherent M phi. Thereafter, conjugates were prepared by incubating for 3 h autologous populations of LAK cells and M phi. Examination of the conjugates by scanning electron microscopy (SEM) identified LAK cell-mediated killing of M phi. Moreover, SEM analysis of the LAK cell membrane architecture identified microvilli-like ultrastructures that provided a physical bridge that joined together the LAK cell and M phi. The immunological mechanism(s) underling LAK cell killing of autologous M phi is not known; nevertheless, these conjugates will provide a useful model to study membrane receptors on ultrastructures that mediate the initial stages of cytolysis that include target cell recognition and cell-to-cell adhesion. The results of our observations and the findings of other investigators who have also demonstrated LAK cell killing of autologous normal human leukocytes are discussed in the context of the association of IL-2 and IL-2-activated killer cells with side effects observed in ongoing clinical trials and with autoimmune disorders.
Klingel, Karin; Fabritius, Cornelia; Sauter, Martina; Göldner, Katrin; Stauch, Diana; Kandolf, Reinhard; Ettischer, Nicole; Gahlen, Sabine; Schönberger, Tanja; Ebner, Susanne; Makrigiannis, Andrew P; Bélanger, Simon; Diefenbach, Andreas; Polić, Bojan; Pratschke, Johann; Kotsch, Katja
2014-10-01
In enterovirus-induced cardiomyopathy, information regarding the detailed impact of natural killer (NK) cells on the outcome of the disease is limited. We therefore hypothesized that NK cells and certain NK cell receptors determine the different outcome of coxsackievirus B3 (CVB3) myocarditis. Here, we demonstrate in murine models that resistance to chronic CVB3 myocarditis in immunocompetent C57BL/6 mice is characterized by significantly more mature CD11b(high) NK cells, the presence of NKG2D on NK cells, and enhanced NKG2D-dependent cytotoxicity compared to CVB3-susceptible A.BY/SnJ mice. The highly protective role of NKG2D in myocarditis was further proven by in vivo neutralization of NKG2D as well as in NKG2D-deficient mice but was shown to be independent of CD8(+) T-cell-dependent immunity. Moreover, the adoptive transfer of immunocompetent C57BL/6 NK cells pre- (day -1) as well as post-infectionem (day +2) displayed the potential to prevent permissive A.BY/SnJ mice from a progressive outcome of CVB3 myocarditis reflected by significantly improved cardiopathology and heart function. Altogether, our results provide firm evidence for a protective role of NKG2D-activated NK cells in CVB3 myocarditis leading to an effective virus clearance, thus offering novel therapeutic options in the treatment of virus-induced myocarditis. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Co-Expansion of Cytokine-Induced Killer Cells and Vγ9Vδ2 T Cells for CAR T-Cell Therapy
Chen, Can; Tan, Wee-Kiat; Chi, Zhixia; Xu, Xue-Hu; Wang, Shu
2016-01-01
Gamma delta (γδ) T cells and cytokine-induced killer (CIK) cells, which are a heterogeneous population of T lymphocytes and natural killer T (NKT) cells, have been separately expanded ex vivo and shown to be capable of targeting and mediating cytotoxicity against various tumor cells in a major histocompatibility complex-unrestricted manner. However, the co-expansion and co-administration of these immune cells have not been explored. In this study we describe an efficient method to expand simultaneously both CIK and Vγ9Vδ2 T cells, termed as CIKZ cells, from human peripheral blood mononuclear cells (PBMCs) using Zometa, interferon-gamma (IFN-γ), interleukin 2 (IL-2), anti-CD3 antibody and engineered K562 feeder cells expressing CD64, CD137L and CD86. A 21-day culture of PBMCs with this method yielded nearly 20,000-fold expansion of CIKZ cells with γδ T cells making up over 20% of the expanded population. The expanded CIKZ cells exhibited antitumor cytotoxicity and could be modified to express anti-CD19 chimeric antigen receptor (CAR), anti-CEA CAR, and anti-HER2 CAR to enhance their specificity and cytotoxicity against CD19-, CEA-, or HER2-positive tumor cells. The tumor inhibitory activity of anti-CD19 CAR-modified CIKZ cells was further demonstrated in vivo in a Raji tumor mouse model. The findings herein substantiate the feasibility of co-expanding CIK and γδ cells for adoptive cellular immunotherapy applications such as CAR T-cell therapy against cancer. PMID:27598655
Zhuang, Yun-Long; Ren, Gui-Jie; Tian, Ke-Li; Li, Xin-Ye; Zhu, Yong-Bao; Liu, Jin-Ling; Si, Gui-Ling; Li, Peng; Zhang, Yi; Wang, Li; Zhang, Wen-Jing; Wang, Da-Jian; Zhu, Chuan-Fu
2012-10-01
Syphilis is a sexually transmitted infection caused by the Treponema pallidum subspecies pallidum spirochete bacterium. The killer cell immunoglobulin-like receptors (KIR), interacting with human leukocyte antigens (HLA), regulate the activations of natural killer (NK) cells and certain T-cell subsets in response to microbe infection. The objective of this study was to explore whether KIR and HLA-C gene polymorphisms were associated with syphilis in a Chinese Han population. Polymerase chain reaction with sequence-specific primers (PCR-SSP) method was used to genotype KIR and HLA-C genes in 231 syphilis patients and 247 healthy controls. Framework genes KIR2DL4, KIR3DL2, KIR3DL3 and KIR3DP1 were present in all individuals. The frequencies of KIR2DS3 and KIR3DS1 were higher in syphilis patients than in healthy controls (p = 0.030 and p = 0.038, respectively), while the frequency of KIR2DS5 was higher in healthy controls than in syphilis patients (p = 0.015; OR = 0.575). The homozygote for HLA-C1 allele (HLA-C1C1) was more common in controls compared with syphilis patients (p = 0.030; OR = 0.667). The frequency of individuals with HLA-C1C1 and KIR2DL3 genotype was higher in control group relative to syphilis patient group (p = 0.018; OR = 0.647). These data indicated that KIR2DS3 and KIR3DS1 were more prevalent in syphilis patients than in controls, and that KIR2DS5, HLA-C1C1 and HLA-C1C1-KIR2DL3 were more prevalent in controls than in syphilis patients, respectively. These will require further investigation using functional studies. © 2012 The Authors APMIS © 2012 APMIS.
Du, Jing; Paz, Katelyn; Thangavelu, Govindarajan; Schneidawind, Dominik; Baker, Jeanette; Flynn, Ryan; Duramad, Omar; Feser, Colby; Panoskaltsis-Mortari, Angela; Negrin, Robert S; Blazar, Bruce R
2017-06-08
Chronic graft-versus-host-disease (cGVHD) can cause multiorgan system disease, typically with autoimmune-like features, resulting in high mortality and morbidity caused by treatment limitations. Invariant natural killer T cells (iNKTs), a small population characterized by expression of a semi-invariant T-cell receptor, rapidly produce copious amounts of diverse cytokines on activation that exert potent immune regulatory function. Here, we show that iNKTs are significantly reduced in a cGVHD murine model that recapitulates several aspects of autoimmunity and organ fibrosis observed in patients with cGVHD. Low iNKT infused doses effectively prevented and, importantly, reversed established cGVHD, as did third-party iNKTs. iNKTs suppressed the autoimmune response by reducing the germinal center (GC) reaction, which was associated with an increase in total Tregs and follicular Tregs (Tfr) that control the GC reaction, along with pathogenic antibody production. Treg depletion during iNKT infusions completely abolished iNKT efficacy in treating cGVHD. iNKT cell interleukin 4 production and GC migration were critical to cGVHD reversal. In vivo stimulation of iNKT cells by α-galactosyl-ceramide was effective in both preventing and treating cGVHD. Together, this study demonstrates iNKT deficiency in cGVHD mice and highlights the key role of iNKTs in regulating cGVHD pathogenesis and as a potentially novel prophylactic and therapeutic option for patients with cGVHD. © 2017 by The American Society of Hematology.
Autoreactive T effector memory differentiation mirrors β-cell function in type 1 diabetes.
Yeo, Lorraine; Woodwyk, Alyssa; Sood, Sanjana; Lorenc, Anna; Eichmann, Martin; Pujol-Autonell, Irma; Melchiotti, Rossella; Skowera, Ania; Fidanis, Efthymios; Dolton, Garry M; Tungatt, Katie; Sewell, Andrew K; Heck, Susanne; Saxena, Alka; Beam, Craig A; Peakman, Mark
2018-05-31
In type 1 diabetes, cytotoxic CD8 T cells with specificity for β-cell autoantigens are found in the pancreatic islets where they are implicated in the destruction of insulin-secreting β cells. In contrast, the disease relevance of β-cell-reactive CD8 T cells that are detectable in the circulation, and their relationship to β-cell function, are not known. Here, we tracked multiple, circulating β-cell-reactive CD8 T cell subsets and measured β-cell function longitudinally for two years, starting immediately after diagnosis of type 1 diabetes. We found that change in β-cell-specific effector memory CD8 T cells expressing CD57 was positively correlated with C-peptide change in subjects below 12 years of age. Autoreactive CD57+ effector memory CD8 T cells bore the signature of enhanced effector function (higher expression of granzyme B, killer specific protein 37 and CD16, and reduced expression of CD28) compared with their CD57-negative counterparts, and network association modelling indicated that the dynamics of β-cell-reactive CD57+ effector memory CD8 T cell subsets were strongly linked. Thus, coordinated changes in circulating β-cell-specific CD8 T cells within the CD57+ effector memory subset calibrate to functional insulin reserve in type 1 diabetes, providing a tool for immune monitoring and a mechanism-based target for immunotherapy.
Herpesvirus Evasion of Natural Killer Cells.
De Pelsmaeker, Steffi; Romero, Nicolas; Vitale, Massimo; Favoreel, Herman W
2018-06-01
Natural killer (NK) cells play an important role in the host response against viral infections and cancer development. They are able to kill virus-infected and tumor cells, and they produce different important cytokines that stimulate the antiviral and antitumor adaptive immune response, particularly interferon gamma. NK cells are of particular importance in herpesvirus infections, which is illustrated by systemic and life-threatening herpesvirus disease symptoms in patients with deficiencies in NK cell activity and by the myriad of reports describing herpesvirus NK cell evasion strategies. The latter is particularly obvious for cytomegaloviruses, but increasing evidence indicates that most, if not all, members of the herpesvirus family suppress NK cell activity to some extent. This review discusses the different NK cell evasion strategies described for herpesviruses and how this knowledge may translate to clinical applications. Copyright © 2018 American Society for Microbiology.
Alecsandru, Diana; García-Velasco, Juan A
2017-06-01
The immune system's role in recurrent reproductive failure is a controversial issue in assisted reproduction. Most studies into immune system implication in reproduction have focused on finding markers of peripheral blood and less on the uterine environment. Peripheral blood natural killer cells have become an "immune study core" for women with recurrent miscarriage or recurrent implantation failure, based on the mistaken notion that they cause reproductive failure by killing or "rejecting" the embryo. Maternal-fetal tolerance begins at the uterine level, so successful adaptation to the fetus occurs after a complicated process. Insufficient uterine lining invasion by an invading extravillous trophoblast is the primary defect in pregnancy disorders such as recurrent miscarriage. This process is regulated by the interaction between maternal killer immunoglobulin-like receptors (KIRs), expressed by uterine natural killer cells (uNK), and their ligand human leukocyte antigen (HLA) C, expressed by the extravillous trophoblast. Pregnancies are an increased risk of disorders in mothers with KIR AA when the fetus has paternal HLA-C2. A recent report has indicated that the expression of more than one paternal HLA-C by the extravillous trophoblast in assisted reproduction may affect placentation in mothers with KIR AA. This review provides insight into the immune system's role in assisted reproductive treatments. These insights can have an impact on the selection of single-embryo transfer and/or oocyte/sperm donor according to HLA-C in patients with recurrent implantation failure and recurrent miscarriage depending on their KIR haplotype. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Eissens, D N; Schaap, N P M; Preijers, F W M B; Dolstra, H; van Cranenbroek, B; Schattenberg, A V M; Joosten, I; van der Meer, A
2010-03-01
Natural killer (NK) cells have an important function in the anti-tumor response early after stem cell transplantation (SCT). As part of a prospective randomized phase III study, directly comparing the use of CD3(+)/CD19(+)-depleted peripheral blood stem cell (PBSC) harvests with CD34(+)-selected PBSC harvests in allogeneic human leukocyte antigen-matched SCT, we here show that the use of CD3(+)/CD19(+)-depleted PBSC grafts leads to early NK cell repopulation and reconstitution of the CD56(dim) and CD56(bright) NK cell subsets, with concomitant high cytolytic capacity. In the CD34 group, this process took significantly longer. Moreover, in the CD3/19 group after reconstitution, a higher percentage of killer immunoglobulin-like receptor-positive NK cells was found. Although similar percentages of CD94-positive NK cells were found in both groups, in the CD34 group, almost all expressed the inhibitory CD94:NKG2A complex, whereas in the CD3/19 group, the inhibitory CD94:NKG2A and the activating CD94:NKG2C complex were equally distributed. This preferential development of NKG2C-expressing NK cells in the CD3/19 group was paralleled by a loss of NKG2A-mediated inhibition of NK cell degranulation. These results show that the use of CD3(+)/CD19(+)-depleted grafts facilitates strong NK cell cytolytic responses directly after SCT, and the rapid emergence of an NK cell receptor phenotype that is more prone to activation.
Frazao, Alexandra; Colombo, Marina; Fourmentraux-Neves, Emmanuelle; Messaoudene, Meriem; Rusakiewicz, Sylvie; Zitvogel, Laurence; Vivier, Eric; Vély, Frédéric; Faure, Florence; Dréno, Brigitte; Benlalam, Houssem; Bouquet, Fanny; Savina, Ariel; Pasmant, Eric; Toubert, Antoine; Avril, Marie-Françoise; Caignard, Anne
2017-07-01
Over 60% of human melanoma tumors bear a mutation in the BRAF gene. The most frequent mutation is a substitution at codon 600 (V600E), leading to a constitutively active BRAF and overactivation of the MAPK pathway. Patients harboring mutated BRAF respond to kinase inhibitors such as vemurafenib. However, these responses are transient, and relapses are frequent. Melanoma cells are efficiently lysed by activated natural killer (NK) cells. Melanoma cells express several stress-induced ligands that are recognized by activating NK-cell receptors. We have investigated the effect of vemurafenib on the immunogenicity of seven BRAF -mutated melanoma cells to NK cells and on their growth and sensitivity to NK-cell-mediated lysis. We showed that vemurafenib treatment modulated expression of ligands for two activating NK receptors, increasing expression of B7-H6, a ligand for NKp30, and decreasing expression of MICA and ULBP2, ligands for NKG2D. Vemurafenib also increased expression of HLA class I and HLA-E molecules, likely leading to higher engagement of inhibitory receptors (KIRs and NKG2A, respectively), and decreased lysis of vemurafenib-treated melanoma cell lines by cytokine-activated NK cells. Finally, we showed that whereas batimastat (a broad-spectrum matrix metalloprotease inhibitor) increased cell surface ULBP2 by reducing its shedding, vemurafenib lowered soluble ULBP2, indicating that BRAF signal inhibition diminished expression of both cell-surface and soluble forms of NKG2D ligands. Vemurafenib, inhibiting BRAF signaling, shifted the balance of activatory and inhibitory NK ligands on melanoma cells and displayed immunoregulatory effects on NK-cell functional activities. Cancer Immunol Res; 5(7); 582-93. ©2017 AACR . ©2017 American Association for Cancer Research.
Varchetta, Stefania; Mele, Dalila; Lombardi, Andrea; Oliviero, Barbara; Mantovani, Stefania; Tinelli, Carmine; Spreafico, Marta; Prati, Daniele; Ludovisi, Serena; Ferraioli, Giovanna; Filice, Carlo; Aghemo, Alessio; Lampertico, Pietro; Facchetti, Floriana; Bernuzzi, Francesca; Invernizzi, Pietro; Mondelli, Mario U
2016-12-01
Sialic-acid-binding immunoglobulin-like lectin-7 (Siglec-7) is a natural killer (NK) cell inhibitory receptor associated with NK phenotypic and functional abnormalities in HIV-1 infection. We investigated the significance of NK-expressed and serum soluble Siglec-7 in relation to NK functional ability and parameters of liver necroinflammation and fibrosis in chronic HCV infection. NK-expressed and serum Siglec-7 were evaluated in 130 and 166 HCV-infected individuals by flow cytometry and ELISA, respectively. NK cell degranulation and cytokine secretion were determined by flow cytometry. 65 patients with chronic HBV infection, 84 with chronic biliary disorders and 168 healthy donors served as controls. Expression of Siglec-7 was significantly decreased on NK cells from HCV-infected and HBV-infected patients and, conversely, serum Siglec-7 was significantly increased in these patients compared with controls. The frequency of Siglec-7pos NK cells was significantly higher at baseline in sustained virological responders to pegylated interferon-α/ribavirin treatment than in non-responders. Activating receptor expression was significantly higher in Siglec-7pos NK cells and was associated with increased degranulation and cytokine secretion compared with Siglec-7 neg cells. In chronic HCV infection, there was an inverse correlation between Siglec-7 expression and serum aminotransferases, γ-glutamyl transpeptidase, liver stiffness, aspartate aminotransferase to platelet ratio index and fibrosis-4 scores, and a positive correlation between serum Siglec-7 and the same clinical parameters, including histological staging. These findings identify Siglec-7 neg NK cells as a dysfunctional subpopulation associated with severe liver disease in chronic HCV infection. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Tracking KLRC2 (NKG2C)+ memory-like NK cells in SIV+ and rhCMV+ rhesus macaques.
Ram, Daniel R; Manickam, Cordelia; Hueber, Brady; Itell, Hannah L; Permar, Sallie R; Varner, Valerie; Reeves, R Keith
2018-05-01
Natural killer (NK) cells classically typify the nonspecific effector arm of the innate immune system, but have recently been shown to possess memory-like properties against multiple viral infections, most notably CMV. Expression of the activating receptor NKG2C is elevated on human NK cells in response to infection with CMV as well as HIV, and may delineate cells with memory and memory-like functions. A better understanding of how NKG2C+ NK cells specifically respond to these pathogens could be significantly advanced using nonhuman primate (NHP) models but, to date, it has not been possible to distinguish NKG2C from its inhibitory counterpart, NKG2A, in NHP because of unfaithful antibody cross-reactivity. Using novel RNA-based flow cytometry, we identify for the first time true memory NKG2C+ NK cells in NHP by gene expression (KLRC2), and show that these cells have elevated frequencies and diversify their functional repertoire specifically in response to rhCMV and SIV infections.
Cyclosporin a inhibits T cell-mediated augmentation of mouse natural killer activity.
Yanagihara, R H; Adler, W H
1982-06-01
Cyclosporin A (CSA) in vitro inhibited the spontaneous cytotoxic activity of mouse spleen cells against YAC target cells in a 4 hr 51Cr release assay. While natural killer (NK) cells were inhibited directly by CSA, these suppressive effects were largely reversible by coculture of effector cells for an optimal period with polyinosinic-polycytidylic acid (Poly I:C) or lipopolysaccharide (LPS). In contrast concanavalin A (Con A), in the presence of CSA, was unable to augment NK activity. The supernatant, however, of mouse spleen cells cultured with Con A was fully able to augment the NK the activity by freshly cultured spleen cells in the presence of CSA. The results indicate that CSA inhibits NK activity by two distinct mechanisms: a) a direct inactivation of NK cells and b) a suppression of production or release of an NK-activating factor from T cells, but not B cells or macrophages.
Effects of Polar Bear and Killer Whale Derived Contaminant Cocktails on Marine Mammal Immunity.
Desforges, Jean-Pierre; Levin, Milton; Jasperse, Lindsay; De Guise, Sylvain; Eulaers, Igor; Letcher, Robert J; Acquarone, Mario; Nordøy, Erling; Folkow, Lars P; Hammer Jensen, Trine; Grøndahl, Carsten; Bertelsen, Mads F; St Leger, Judy; Almunia, Javier; Sonne, Christian; Dietz, Rune
2017-10-03
Most controlled toxicity studies use single chemical exposures that do not represent the real world situation of complex mixtures of known and unknown natural and anthropogenic substances. In the present study, complex contaminant cocktails derived from the blubber of polar bears (PB; Ursus maritimus) and killer whales (KW; Orcinus orca) were used for in vitro concentration-response experiments with PB, cetacean and seal spp. immune cells to evaluate the effect of realistic contaminant mixtures on various immune functions. Cytotoxic effects of the PB cocktail occurred at lower concentrations than the KW cocktail (1 vs 16 μg/mL), likely due to differences in contaminant profiles in the mixtures derived from the adipose of each species. Similarly, significant reduction of lymphocyte proliferation occurred at much lower exposures in the PB cocktail (EC 50 : 0.94 vs 6.06 μg/mL; P < 0.01), whereas the KW cocktail caused a much faster decline in proliferation (slope: 2.9 vs 1.7; P = 0.04). Only the KW cocktail modulated natural killer (NK) cell activity and neutrophil and monocyte phagocytosis in a concentration- and species-dependent manner. No clear sensitivity differences emerged when comparing cetaceans, seals and PB. Our results showing lower effect levels for complex mixtures relative to single compounds suggest that previous risk assessments underestimate the effects of real world contaminant exposure on immunity. Our results using blubber-derived contaminant cocktails add realism to in vitro exposure experiments and confirm the immunotoxic risk marine mammals face from exposure to complex mixtures of environmental contaminants.
ElAlfy, Mohsen Saleh; Adly, Amira Abdel Moneam; Ebeid, Fatma Soliman ElSayed; Eissa, Deena Samir; Ismail, Eman Abdel Rahman; Mohammed, Yasser Hassan; Ahmed, Manar Elsayed; Saad, Aya Sayed
2018-06-20
Sickle cell disease (SCD) is associated with alterations in immune phenotypes. CD4 + CD28 null T lymphocytes have pro-inflammatory functions and are linked to vascular diseases. To assess the percentage of CD4 + CD28 null T lymphocytes, natural killer cells (NK), and IFN-gamma levels, we compared 40 children and adolescents with SCD with 40 healthy controls and evaluated their relation to disease severity and response to therapy. Patients with SCD steady state were studied, focusing on history of frequent vaso-occlusive crisis, hydroxyurea therapy, and IFN-gamma levels. Analysis of CD4 + CD28 null T lymphocytes and NK cells was done by flow cytometry. Liver and cardiac iron overload were assessed. CD4 + CD28 null T lymphocytes, NK cells, and IFN-gamma levels were significantly higher in patients than controls. Patients with history of frequent vaso-occlusive crisis and those with vascular complications had higher percentage of CD4 + CD28 null T lymphocytes and IFN-gamma while levels were significantly lower among hydroxyurea-treated patients. CD4 + CD28 null T lymphocytes were positively correlated to transfusional iron input while these cells and IFN-gamma were negatively correlated to cardiac T2* and duration of hydroxyurea therapy. NK cells were correlated to HbS and indirect bilirubin. Increased expression of CD4 + CD28 null T lymphocytes highlights their role in immune dysfunction and pathophysiology of SCD complications.
Hammer, Quirin; Rückert, Timo; Borst, Eva Maria; Dunst, Josefine; Haubner, André; Durek, Pawel; Heinrich, Frederik; Gasparoni, Gilles; Babic, Marina; Tomic, Adriana; Pietra, Gabriella; Nienen, Mikalai; Blau, Igor Wolfgang; Hofmann, Jörg; Na, Il-Kang; Prinz, Immo; Koenecke, Christian; Hemmati, Philipp; Babel, Nina; Arnold, Renate; Walter, Jörn; Thurley, Kevin; Mashreghi, Mir-Farzin; Messerle, Martin; Romagnani, Chiara
2018-05-01
Natural killer (NK) cells are innate lymphocytes that lack antigen-specific rearranged receptors, a hallmark of adaptive lymphocytes. In some people infected with human cytomegalovirus (HCMV), an NK cell subset expressing the activating receptor NKG2C undergoes clonal-like expansion that partially resembles anti-viral adaptive responses. However, the viral ligand that drives the activation and differentiation of adaptive NKG2C + NK cells has remained unclear. Here we found that adaptive NKG2C + NK cells differentially recognized distinct HCMV strains encoding variable UL40 peptides that, in combination with pro-inflammatory signals, controlled the population expansion and differentiation of adaptive NKG2C + NK cells. Thus, we propose that polymorphic HCMV peptides contribute to shaping of the heterogeneity of adaptive NKG2C + NK cell populations among HCMV-seropositive people.
Shimada, Shigeki; Takeda, Masamitsu; Nishihira, Jun; Kaneuchi, Masanori; Sakuragi, Noriaki; Minakami, Hisanori; Yamada, Hideto
2009-11-01
A high dose of intravenous immunoglobulin (HIVIg) therapy is effective in various diseases such as autoimmune diseases, and also is expected to have efficacy in recurrent spontaneous abortion (RSA). The aim of this study was to understand immunological mechanisms of this therapy. By flowcytometric analyses, we examined phenotypic changes of a variety of immunological cells including natural killer (NK) cells, cytotoxic T cells, regulatory T cells and macrophages in peripheral blood of RSA women with HIVIg therapy (n = 8). Expression percentages of inhibitory CD94 on NK cells significantly (P = 0.01) increased after the therapy (58.8 +/- 21.4% versus 71.0 +/- 17.6%). Mechanisms of possible efficacy of HIVIg therapy for RSA may include enhancement of CD94 expression and subsequent suppression of NK cell cytotoxicity.
Peng, Yuan; Huang, Kai; Shen, Li; Tao, Yan-yan; Liu, Cheng-hai
2016-02-01
Recent evidence shows that cultured mycelium Cordyceps sinensis (CMCS) effectively protects against liver fibrosis in mice. Here, we investigated whether the anti-fibrotic action of CMCS was related to its regulation of the activity of hepatic natural killer (NK) cells in CCl4-treated mice. C57BL/6 mice were injected with 10% CCl4 (2 mL/kg, ip) 3 times per week for 4 weeks, and received CMCS (120 mg·kg(-1)·d(-1), ig) during this period. In another part of experiments, the mice were also injected with an NK cell-deleting antibody ASGM-1 (20 μg, ip) 5 times in the first 3 weeks. After the mice were sacrificed, serum liver function, and liver inflammation, hydroxyproline content and collagen deposition were assessed. The numbers of hepatic NK cells and expression of NKG2D (activation receptor of NK cells) on isolated liver lymphocytes were analyzed using flow cytometry. Desmin expression and cell apoptosis in liver tissues were studied using desmin staining and TUNEL assay, respectively. The levels of α-SMA, TGF-β, RAE-1δ and RAE-1ε in liver tissues were determined by RT-qPCR. In CCl4-treated mice, CMCS administration significantly improved liver function, attenuated liver inflammation and fibrosis, and increased the numbers of hepatic NK cells and expression level of NKG2D on hepatic NK cells. Furthermore, CMCS administration significantly decreased desmin expression in liver tissues, and increased TUNEL staining adjacent to hepatic stellate cells. Injection with NK cell-deleting ASGM-1 not only diminished the numbers of hepatic NK cells, but also greatly accelerated liver inflammation and fibrosis in CCl4-treated mice. In CCl4-treated mice with NK cell depletion, CMCS administration decelerated the rate of liver fibrosis development, and mildly upregulated the numbers of hepatic NK cells but without changing NKG2D expression. CMCS alleviates CCl4-induced liver inflammation and fibrosis via promoting activation of hepatic NK cells. CMCS partially reverses ASGM-1-induced depletion of hepatic NK cells.
Schmidt, Stanislaw; Tramsen, Lars; Perkhofer, Susanne; Lass-Flörl, Cornelia; Hanisch, Mitra; Röger, Frauke; Klingebiel, Thomas; Koehl, Ulrike; Lehrnbecher, Thomas
2013-07-01
Mucormycosis has a high mortality and is increasingly diagnosed in hematopoietic stem cell transplant (HSCT) recipients. In this setting, there is a growing interest to restore host defense to combat infections by adoptively transferring donor-derived immunocompetent cells. Natural killer (NK) cells exhibit antitumor and antiinfective activity, but the interaction with Mucormycetes is unknown. Our data demonstrate that both unstimulated and IL-2 prestimulated human NK cells damage Rhizopus oryzae hyphae, but do not affect resting conidia. The damage of the fungus is mediated, at least in part, by perforin. R. oryzae hyphae decrease the secretion of immunoregulatory molecules by NK cells, such as IFN-γ and RANTES, indicating an immunosuppressive effect of the fungus. Our data indicate that NK cells exhibit activity against Mucormycetes and future research should evaluate NK cells as a potential tool for adoptive immunotherapy in HSCT. Copyright © 2012 Elsevier GmbH. All rights reserved.
Lemieszek, Marta Kinga; Nunes, Fernando Herminio Ferreira Milheiro; Sawa-Wejksza, Katarzyna; Rzeski, Wojciech
2017-01-01
Numerous studies indicate the crucial role of natural killer (NK) cells in the prevention of tumor growth and inhibition of their metastasis, which suggests the possibility of their use in cancer treatment. This therapeutic strategy required finding a selective NK cell stimulator that, upon administration, did not disturb organism homeostasis, unlike natural activators (interleukin-2 or interleukin-12). Because the majority of anticancer agents derived from Basidiomycetes are able to stimulate lymphocytes, we describe the influence of Boletus edulis RNA on a human NK cell line (NK92). Our studies showed that a B. edulis RNA fraction was not toxic against NK92 cells. Furthermore, the tested fraction significantly stimulated NK92 cell proliferation and their cytotoxicity against tumor cells. We demonstrate here, to our knowledge for the first time, that B. edulis RNA enhances NK cell activity and possesses immunomodulatory potential.
Confinement of activating receptors at the plasma membrane controls natural killer cell tolerance.
Guia, Sophie; Jaeger, Baptiste N; Piatek, Stefan; Mailfert, Sébastien; Trombik, Tomasz; Fenis, Aurore; Chevrier, Nicolas; Walzer, Thierry; Kerdiles, Yann M; Marguet, Didier; Vivier, Eric; Ugolini, Sophie
2011-04-05
Natural killer (NK) cell tolerance to self is partly ensured by major histocompatibility complex (MHC) class I-specific inhibitory receptors on NK cells, which dampen their reactivity when engaged. However, NK cells that do not detect self MHC class I are not autoreactive. We used dynamic fluorescence correlation spectroscopy to show that MHC class I-independent NK cell tolerance in mice was associated with the presence of hyporesponsive NK cells in which both activating and inhibitory receptors were confined in an actin meshwork at the plasma membrane. In contrast, the recognition of self MHC class I by inhibitory receptors "educated" NK cells to become fully reactive, and activating NK cell receptors became dynamically compartmentalized in membrane nanodomains. We propose that the confinement of activating receptors at the plasma membrane is pivotal to ensuring the self-tolerance of NK cells.
Adrenomedullin and endocrine control of immune cells during pregnancy.
Matson, Brooke C; Caron, Kathleen M
2014-09-01
The immunology of pregnancy is complex and incompletely understood. Aberrant immune activity in the decidua and in the placenta is believed to play a role in diseases of pregnancy, such as infertility, miscarriage, fetal growth restriction and preeclampsia. Here, we briefly review the endocrine control of uterine natural killer cell populations and their functions by the peptide hormone adrenomedullin. Studies in genetic animal models have revealed the critical importance of adrenomedullin dosage at the maternal-fetal interface, with cells from both the maternal and fetal compartments contributing to essential aspects underlying appropriate uterine receptivity, implantation and vascular remodeling of spiral arteries. These basic insights into the crosstalk between the endocrine and immune systems within the maternal-fetal interface may ultimately translate to a better understanding of the functions and consequences of dysregulated adrenomedullin levels in clinically complicated pregnancies.
Clinical-Grade Human Multipotent Adult Progenitor Cells Block CD8+ Cytotoxic T Lymphocytes
Dekimpe, Emily; Van Woensel, Matthias; Roobrouck, Valerie D.; Bullens, Dominique M.; Pinxteren, Jef; Verfaillie, Catherine M.; Van Gool, Stefaan W.
2016-01-01
MultiStem cells are clinical-grade multipotent adult bone marrow-derived progenitor cells (MAPCs), with extensive replication potential and broader differentiation capacity compared with mesenchymal stem cells. Human MAPCs suppress T-cell proliferation induced by alloantigens and mutually interact with allogeneic natural killer cells. In this study, the interaction between MultiStem and CD8+ cytotoxic T lymphocytes (CTLs) was addressed for the first time. In an in vitro setting, the immunogenicity of MultiStem, the susceptibility of MultiStem toward CTL-mediated lysis, and its effects on CTL function were investigated. MultiStem was nonimmunogenic for alloreactive CTL induction and was—even after major histocompatibility complex class I upregulation—insensitive to alloantigen-specific CTL-mediated lysis. Furthermore, MultiStem reduced CTL proliferation and significantly decreased perforin expression during the T-cell activation phase. As a consequence, MultiStem dose-dependently impaired the induction of CTL function. These effects of MultiStem were mediated predominantly through contact-dependent mechanisms. Moreover, MultiStem cells considerably influenced the expression of T-cell activation markers CD25, CD69, and human leukocyte antigen-DR. The MultiStem-induced CD8−CD69+ T-cell population displayed a suppressive effect on the induction of CTL function during a subsequent mixed-lymphocyte culture. Finally, the killer activity of activated antigen-specific CTLs during their cytolytic effector phase was also diminished in the presence of MultiStem. This study confirms that these clinical-grade MAPCs are an immune-modulating population that inhibits CTL activation and effector responses and are, consequently, a highly valuable cell population for adoptive immunosuppressive therapy in diseases where damage is induced by CTLs. Significance Because multipotent adult progenitor cells (MAPCs) are among the noteworthy adult mesenchymal stem cell populations for immune therapy and have the advantage over mesenchymal stem cells (MSCs) of large-scale manufacturing and banking potential and thus prompt availability, it is important to understand how MAPCs interact with immune cells to validate their widespread therapeutic applicability. Cytotoxic immune effector cells play a crucial role in immune homeostasis and in the pathogenesis of some autoimmune diseases. This study assessed for the first time the in vitro influence of a clinical-grade human MAPC product (MultiStem) on the cytotoxic function of CD8+ T cells (CTLs) by evaluating the immunogenicity of MAPCs and the susceptibility of MAPCs toward CTL-mediated lysis and by analyzing the mechanism of MAPC-mediated modulation of CTL functionality. These results may represent a highly relevant contribution to the current knowledge and, in combination with the results of future phase II/III trials using MultiStem, could lead to an intriguing continuation of stem cell-based research for immunotherapy. PMID:27465071
Clinical-Grade Human Multipotent Adult Progenitor Cells Block CD8+ Cytotoxic T Lymphocytes.
Plessers, Jeroen; Dekimpe, Emily; Van Woensel, Matthias; Roobrouck, Valerie D; Bullens, Dominique M; Pinxteren, Jef; Verfaillie, Catherine M; Van Gool, Stefaan W
2016-12-01
: MultiStem cells are clinical-grade multipotent adult bone marrow-derived progenitor cells (MAPCs), with extensive replication potential and broader differentiation capacity compared with mesenchymal stem cells. Human MAPCs suppress T-cell proliferation induced by alloantigens and mutually interact with allogeneic natural killer cells. In this study, the interaction between MultiStem and CD8 + cytotoxic T lymphocytes (CTLs) was addressed for the first time. In an in vitro setting, the immunogenicity of MultiStem, the susceptibility of MultiStem toward CTL-mediated lysis, and its effects on CTL function were investigated. MultiStem was nonimmunogenic for alloreactive CTL induction and was-even after major histocompatibility complex class I upregulation-insensitive to alloantigen-specific CTL-mediated lysis. Furthermore, MultiStem reduced CTL proliferation and significantly decreased perforin expression during the T-cell activation phase. As a consequence, MultiStem dose-dependently impaired the induction of CTL function. These effects of MultiStem were mediated predominantly through contact-dependent mechanisms. Moreover, MultiStem cells considerably influenced the expression of T-cell activation markers CD25, CD69, and human leukocyte antigen-DR. The MultiStem-induced CD8 - CD69 + T-cell population displayed a suppressive effect on the induction of CTL function during a subsequent mixed-lymphocyte culture. Finally, the killer activity of activated antigen-specific CTLs during their cytolytic effector phase was also diminished in the presence of MultiStem. This study confirms that these clinical-grade MAPCs are an immune-modulating population that inhibits CTL activation and effector responses and are, consequently, a highly valuable cell population for adoptive immunosuppressive therapy in diseases where damage is induced by CTLs. Because multipotent adult progenitor cells (MAPCs) are among the noteworthy adult mesenchymal stem cell populations for immune therapy and have the advantage over mesenchymal stem cells (MSCs) of large-scale manufacturing and banking potential and thus prompt availability, it is important to understand how MAPCs interact with immune cells to validate their widespread therapeutic applicability. Cytotoxic immune effector cells play a crucial role in immune homeostasis and in the pathogenesis of some autoimmune diseases. This study assessed for the first time the in vitro influence of a clinical-grade human MAPC product (MultiStem) on the cytotoxic function of CD8 + T cells (CTLs) by evaluating the immunogenicity of MAPCs and the susceptibility of MAPCs toward CTL-mediated lysis and by analyzing the mechanism of MAPC-mediated modulation of CTL functionality. These results may represent a highly relevant contribution to the current knowledge and, in combination with the results of future phase II/III trials using MultiStem, could lead to an intriguing continuation of stem cell-based research for immunotherapy. ©AlphaMed Press.
Saeki, Y; Ishiyama, K; Ishida, N; Tanaka, Y; Ohdan, H
Both liver natural killer (NK) and NK T cells of the innate immune system play a crucial role in islet graft loss after intraportal islet transplantation, although a relationship between NK and NK T cells in islet loss has not been proven. In this study, we investigated the role of NK cells in the innate immune system in islet graft loss after intraportal islet transplantation. To investigate the involvement of liver NK cells in islet destruction, we assessed the differences in graft survival after intraportal islet transplantation between CD1d -/- diabetic mice and NK cell-depleted CD1d -/- diabetic mice. The transplantation of 400 islets into the liver was sufficient to reverse hyperglycemia in wild-type diabetic mice (100%, 4/4). However, normoglycemia could not be achieved when 200 islets were transplanted (0%, 0/4). In contrast, intraportal transplantation of 200 islets in NK cell-depleted CD1d -/- diabetic mice ameliorated hyperglycemia in 71% of cases (5/7), whereas transplantation of the same number of islets in CD1d -/- diabetic mice did not (0%, 0/4). Histologic findings also confirmed that intact islets were observed in NK cell-depleted CD1d -/- diabetic mice, but were difficult to observe in CD1d -/- diabetic mice. The involvement of liver NK cells in the innate immune system related to islet graft loss after intraportal islet transplantation is revealed by improved graft survival and function in NK cell-depleted CD1d -/- diabetic mice. Our data reveal that regulation of NK cell activity is particularly important when insufficient islet numbers are used for transplantation. Copyright © 2016 Elsevier Inc. All rights reserved.
Kinome Analysis of Receptor-Induced Phosphorylation in Human Natural Killer Cells
König, Sebastian; Nimtz, Manfred; Scheiter, Maxi; Ljunggren, Hans-Gustaf; Bryceson, Yenan T.; Jänsch, Lothar
2012-01-01
Background Natural killer (NK) cells contribute to the defense against infected and transformed cells through the engagement of multiple germline-encoded activation receptors. Stimulation of the Fc receptor CD16 alone is sufficient for NK cell activation, whereas other receptors, such as 2B4 (CD244) and DNAM-1 (CD226), act synergistically. After receptor engagement, protein kinases play a major role in signaling networks controlling NK cell effector functions. However, it has not been characterized systematically which of all kinases encoded by the human genome (kinome) are involved in NK cell activation. Results A kinase-selective phosphoproteome approach enabled the determination of 188 kinases expressed in human NK cells. Crosslinking of CD16 as well as 2B4 and DNAM-1 revealed a total of 313 distinct kinase phosphorylation sites on 109 different kinases. Phosphorylation sites on 21 kinases were similarly regulated after engagement of either CD16 or co-engagement of 2B4 and DNAM-1. Among those, increased phosphorylation of FYN, KCC2G (CAMK2), FES, and AAK1, as well as the reduced phosphorylation of MARK2, were reproducibly observed both after engagement of CD16 and co-engagement of 2B4 and DNAM-1. Notably, only one phosphorylation on PAK4 was differentally regulated. Conclusions The present study has identified a significant portion of the NK cell kinome and defined novel phosphorylation sites in primary lymphocytes. Regulated phosphorylations observed in the early phase of NK cell activation imply these kinases are involved in NK cell signaling. Taken together, this study suggests a largely shared signaling pathway downstream of distinct activation receptors and constitutes a valuable resource for further elucidating the regulation of NK cell effector responses. PMID:22238634
Srivastava, Raghvendra M; Trivedi, Sumita; Concha-Benavente, Fernando; Gibson, Sandra P; Reeder, Carly; Ferrone, Soldano; Ferris, Robert L
2017-02-01
Cetuximab, an EGFR-specific antibody (mAb), modestly improves clinical outcome in patients with head and neck cancer (HNC). Cetuximab mediates natural killer (NK) cell:dendritic cell (DC) cross-talk by cross-linking FcγRIIIa, which is important for inducing antitumor cellular immunity. Cetuximab-activated NK cells upregulate the costimulatory receptor CD137 (4-1BB), which, when triggered by agonistic mAb urelumab, might enhance NK-cell functions, to promote T-cell-based immunity. CD137 expression on tumor-infiltrating lymphocytes was evaluated in a prospective cetuximab neoadjuvant trial, and CD137 stimulation was evaluated in a phase Ib trial, in combining agonistic urelumab with cetuximab. Flow cytometry and cytokine release assays using NK cells and DC were used in vitro, testing the addition of urelumab to cetuximab-activated NK, DC, and cross presentation to T cells. CD137 agonist mAb urelumab enhanced cetuximab-activated NK-cell survival, DC maturation, and tumor antigen cross-presentation. Urelumab boosted DC maturation markers, CD86 and HLA DR, and antigen-processing machinery (APM) components TAP1/2, leading to increased tumor antigen cross-presentation. In neoadjuvant cetuximab-treated patients with HNC, upregulation of CD137 by intratumoral, cetuximab-activated NK cells correlated with FcγRIIIa V/F polymorphism and predicted clinical response. Moreover, immune biomarker modulation was observed in an open label, phase Ib clinical trial, of patients with HNC treated with cetuximab plus urelumab. These results suggest a beneficial effect of combination immunotherapy using cetuximab and CD137 agonist in HNC. Clin Cancer Res; 23(3); 707-16. ©2016 AACR. ©2016 American Association for Cancer Research.
Cribbs, Adam; Hookway, Edward S; Wells, Graham; Lindow, Morten; Obad, Susanna; Oerum, Henrik; Prinjha, Rab K; Athanasou, Nick; Sowman, Aneka; Philpott, Martin; Penn, Henry; Soderstrom, Kalle; Feldmann, Marc; Oppermann, Udo
2018-02-16
Natural killer (NK) cells are innate lymphocytes, important in immune surveillance and elimination of stressed, transformed, or virus-infected cells. They critically shape the inflammatory cytokine environment to orchestrate interactions of cells of the innate and adaptive immune systems. Some studies have reported that NK cell activation and cytokine secretion are controlled epigenetically but have yielded only limited insight into the mechanisms. Using chemical screening with small-molecule inhibitors of chromatin methylation and acetylation, further validated by knockdown approaches, we here identified Jumonji-type histone H3K27 demethylases as key regulators of cytokine production in human NK cell subsets. The prototypic JMJD3/UTX (Jumonji domain-containing protein 3) H3K27 demethylase inhibitor GSK-J4 increased global levels of the repressive H3K27me3 mark around transcription start sites of effector cytokine genes. Moreover, GSK-J4 reduced IFN-γ, TNFα, granulocyte-macrophage colony-stimulating factor (GM-CSF), and interleukin-10 levels in cytokine-stimulated NK cells while sparing their cytotoxic killing activity against cancer cells. The anti-inflammatory effect of GSK-J4 in NK cell subsets, isolated from peripheral blood or tissue from individuals with rheumatoid arthritis (RA), coupled with an inhibitory effect on formation of bone-resorbing osteoclasts, suggested that histone demethylase inhibition has broad utility for modulating immune and inflammatory responses. Overall, our results indicate that H3K27me3 is a dynamic and important epigenetic modification during NK cell activation and that JMJD3/UTX-driven H3K27 demethylation is critical for NK cell function. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.
STAT3 is a critical cell-intrinsic regulator of human unconventional T cell numbers and function
Wilson, Robert P.; Ives, Megan L.; Rao, Geetha; Lau, Anthony; Payne, Kathryn; Kobayashi, Masao; Arkwright, Peter D.; Peake, Jane; Wong, Melanie; Adelstein, Stephen; Smart, Joanne M.; French, Martyn A.; Fulcher, David A.; Picard, Capucine; Bustamante, Jacinta; Boisson-Dupuis, Stephanie; Gray, Paul; Stepensky, Polina; Warnatz, Klaus; Freeman, Alexandra F.; Rossjohn, Jamie; McCluskey, James; Holland, Steven M.; Casanova, Jean-Laurent; Uzel, Gulbu; Ma, Cindy S.
2015-01-01
Unconventional T cells such as γδ T cells, natural killer T cells (NKT cells) and mucosal-associated invariant T cells (MAIT cells) are a major component of the immune system; however, the cytokine signaling pathways that control their development and function in humans are unknown. Primary immunodeficiencies caused by single gene mutations provide a unique opportunity to investigate the role of specific molecules in regulating human lymphocyte development and function. We found that individuals with loss-of-function mutations in STAT3 had reduced numbers of peripheral blood MAIT and NKT but not γδ T cells. Analysis of STAT3 mosaic individuals revealed that this effect was cell intrinsic. Surprisingly, the residual STAT3-deficient MAIT cells expressed normal levels of the transcription factor RORγt. Despite this, they displayed a deficiency in secretion of IL-17A and IL-17F, but were able to secrete normal levels of cytokines such as IFNγ and TNF. The deficiency in MAIT and NKT cells in STAT3-deficient patients was mirrored by loss-of-function mutations in IL12RB1 and IL21R, respectively. Thus, these results reveal for the first time the essential role of STAT3 signaling downstream of IL-23R and IL-21R in controlling human MAIT and NKT cell numbers. PMID:25941256
Vallejo, Abbe N.; Mueller, Robert G.; Hamel, David L.; Way, Amanda; Dvergsten, Jeffrey A.; Griffin, Patricia; Newman, Anne B.
2010-01-01
As the repertoire of αβT cell receptors (TCR) contracts with advancing age, there is an associated age-dependent accumulation of oligoclonal T cells expressing of a variety of receptors (NKR), normally expressed on natural killer (NK) cells. Evidences for differential regulation of expression of particular NKRs between T cells and NK cells suggest that NKR expression on T cells is physiologically programmed rather than a random event of the aging process. Experimental studies show NKRs on aged αβT cells may function either as independent receptors, and/or as costimulatory receptors to the TCR. Considering the reported deficits of conventional αβTCR-driven activation and also functional deficits of classical NK cells, NKR+ αβT cells likely represent novel immune effectors that are capable of combining innate and adaptive functions. Inasmuch as immunity is a determinant of individual fitness, the type and density of NKRs could be important contributing factors to the wide heterogeneity of health characteristics of older adults, ranging from institutionalized frail elders who are unable to mount immune responses to functionally independent community-dwelling elders who exhibit protective immunity. Understanding the biology of NKR+ αβT cells could lead to new avenues for age-specific intervention to improve protective immunity. PMID:20932941