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Sample records for activated nkt cells

  1. Chronic alcohol consumption enhances iNKT cell maturation and activation.

    PubMed

    Zhang, Hui; Zhang, Faya; Zhu, Zhaohui; Luong, Dung; Meadows, Gary G

    2015-01-15

    Alcohol consumption exhibits diverse effects on different types of immune cells. NKT cells are a unique T cell population and play important immunoregulatory roles in different types of immune responses. The effects of chronic alcohol consumption on NKT cells remain to be elucidated. Using a mouse model of chronic alcohol consumption, we found that alcohol increases the percentage of NKT cells, especially iNKT cells in the thymus and liver, but not in the spleen or blood. Alcohol consumption decreases the percentage of NK1.1(-) iNKT cells in the total iNKT cell population in all of the tissues and organs examined. In the thymus, alcohol consumption increases the number of NK1.1(+)CD44(hi) mature iNKT cells but does not alter the number of NK1.1(-) immature iNKT cells. A BrdU incorporation assay shows that alcohol consumption increases the proliferation of thymic NK1.1(-) iNKT cells, especially the NK1.1(-)CD44(lo) Stage I iNKT cells. The percentage of NKG2A(+) iNKT cells increases in all of the tissues and organs examined; whereas CXCR3(+) iNKT cells only increases in the thymus of alcohol-consuming mice. Chronic alcohol consumption increases the percentage of IFN-γ-producing iNKT cells and increases the blood concentration of IFN-γ and IL-12 after in vivo α-galactosylceramide (αGalCer) stimulation. Consistent with the increased cytokine production, the in vivo activation of iNKT cells also enhances the activation of dendritic cells (DC) and NK, B, and T cells in the alcohol-consuming mice. Taken together the data indicate that chronic alcohol consumption enhances iNKT cell maturation and activation, which favors the Th1 immune response. PMID:25499027

  2. Chronic alcohol consumption enhances iNKT cell maturation and activation

    SciTech Connect

    Zhang, Hui Zhang, Faya; Zhu, Zhaohui; Luong, Dung; Meadows, Gary G.

    2015-01-15

    Alcohol consumption exhibits diverse effects on different types of immune cells. NKT cells are a unique T cell population and play important immunoregulatory roles in different types of immune responses. The effects of chronic alcohol consumption on NKT cells remain to be elucidated. Using a mouse model of chronic alcohol consumption, we found that alcohol increases the percentage of NKT cells, especially iNKT cells in the thymus and liver, but not in the spleen or blood. Alcohol consumption decreases the percentage of NK1.1{sup −} iNKT cells in the total iNKT cell population in all of the tissues and organs examined. In the thymus, alcohol consumption increases the number of NK1.1{sup +}CD44{sup hi} mature iNKT cells but does not alter the number of NK1.1{sup −} immature iNKT cells. A BrdU incorporation assay shows that alcohol consumption increases the proliferation of thymic NK1.1{sup −} iNKT cells, especially the NK1.1{sup −}CD44{sup lo} Stage I iNKT cells. The percentage of NKG2A{sup +} iNKT cells increases in all of the tissues and organs examined; whereas CXCR3{sup +} iNKT cells only increases in the thymus of alcohol-consuming mice. Chronic alcohol consumption increases the percentage of IFN-γ-producing iNKT cells and increases the blood concentration of IFN-γ and IL-12 after in vivo α-galactosylceramide (αGalCer) stimulation. Consistent with the increased cytokine production, the in vivo activation of iNKT cells also enhances the activation of dendritic cells (DC) and NK, B, and T cells in the alcohol-consuming mice. Taken together the data indicate that chronic alcohol consumption enhances iNKT cell maturation and activation, which favors the Th1 immune response. - Highlights: • Chronic alcohol consumption increases iNKT cells in the thymus and liver • Chronic alcohol consumption enhances thymic Stage I iNKT cell proliferation • Chronic alcohol consumption enhances iNKT cell maturation in thymus and periphery • Chronic alcohol

  3. Langerhans Cells Serve as Immunoregulatory Cells by Activating NKT Cells1

    PubMed Central

    Fukunaga, Atsushi; Khaskhely, Noor M.; Ma, Ying; Sreevidya, Coimbatore S.; Taguchi, Kumiko; Nishigori, Chikako; Ullrich, Stephen E.

    2010-01-01

    UV exposure alters the morphology and function of epidermal Langerhans cells, which plays a role in UV-induced immune suppression. It is generally believed that UV exposure triggers the migration of immature Langerhans cells (LC) from the skin to the draining lymph nodes, where they induce tolerance. However, because most of the previous studies employed in vitro UV-irradiated LC, the data generated may not adequately reflect what is happening in vivo. In this study we isolated migrating Langerhans cells from the lymph nodes of UV-irradiated mice and studied their function. We found prolonged LC survival in the lymph nodes of UV-irradiated mice. LC were necessary for UV-induced immune suppression because no immune suppression was observed in Langerhans cells-deficient mice. Transferring LC from UV-irradiated mice into normal recipient animals transferred immune suppression and induced tolerance. We found that LC co-localized with lymph node Natural Killer T (NKT) cells. No immune suppression was observed when LC were transferred from UV-irradiated mice into NKT cell-deficient mice. NKT cells isolated from the lymph nodes of UV-irradiated mice secreted significantly more IL-4 than NKT cells isolated from non-irradiated controls. Injecting the wild type mice with anti-IL-4 blocked the induction of immune suppression. Our findings indicate that UV exposure activates the migration of mature LC to the skin draining lymph nodes where they induce immune regulation in vivo by activating NKT cells. PMID:20844203

  4. Activated NKT cells imprint NK-cell differentiation, functionality and education.

    PubMed

    Riese, Peggy; Trittel, Stephanie; May, Tobias; Cicin-Sain, Luka; Chambers, Benedict J; Guzmán, Carlos A

    2015-06-01

    NK cells represent a vital component of the innate immune system. The recent discoveries demonstrating that the functionality of NK cells depends on their differentiation and education status underscore their potential as targets for immune intervention. However, to exploit their full potential, a detailed understanding of the cellular interactions involved in these processes is required. In this regard, the cross-talk between NKT cells and NK cells needs to be better understood. Our results provide strong evidence for NKT cell-induced effects on key biological features of NK cells. NKT-cell activation results in the generation of highly active CD27(high) NK cells with improved functionality. In this context, degranulation activity and IFNγ production were mainly detected in the educated subset. In a mCMV infection model, we also demonstrated that NKT-cell stimulation induced the generation of highly functional educated and uneducated NK cells, crucial players in viral control. Thus, our findings reveal new fundamental aspects of the NKT-NK cell axis that provide important hints for the manipulation of NK cells in clinical settings. PMID:25808315

  5. Activation of murine invariant NKT cells promotes susceptibility to candidiasis by IL-10 induced modulation of phagocyte antifungal activity.

    PubMed

    Haraguchi, Norihiro; Kikuchi, Norihiro; Morishima, Yuko; Matsuyama, Masashi; Sakurai, Hirofumi; Shibuya, Akira; Shibuya, Kazuko; Taniguchi, Masaru; Ishii, Yukio

    2016-07-01

    Invariant NKT (iNKT) cells play an important role in a variety of antimicrobial immune responses due to their ability to produce high levels of immune-modulating cytokines. Here, we investigated the role of iNKT cells in host defense against candidiasis using Jα18-deficient mice (Jα18(-/-) ), which lack iNKT cells. Jα18(-/-) mice were more resistant to the development of lethal candidiasis than wild-type (WT) mice. In contrast, treatment of WT mice with the iNKT cell activating ligand α-galactosylceramide markedly enhanced their mortality after infection with Candida albicans. Serum IL-10 levels were significantly elevated in WT mice in response to infection with C. albicans. Futhermore, IL-10 production increased after in vitro coculture of peritoneal macrophages with iNKT cells and C. albicans. The numbers of peritoneal macrophages, the production of IL-1β and IL-18, and caspase-1 activity were also significantly elevated in Jα18(-/-) mice after infection with C. albicans. The adoptive transfer of iNKT cells or exogenous administration of IL-10 into Jα18(-/-) reversed susceptibility to candidiasis to the level of WT mice. These results suggest that activation of iNKT cells increases the initial severity of C. albicans infection, most likely mediated by IL-10 induced modulation of macrophage antifungal activity. PMID:27151377

  6. NKT cell activation by local α-galactosylceramide administration decreases susceptibility to HSV-2 infection.

    PubMed

    Iversen, Marie Beck; Jensen, Simon Kok; Hansen, Anne Louise; Winther, Henriette; Issazadeh-Navikas, Shohreh; Reinert, Line Sinnathamby; Holm, Christian Kanstrup

    2015-06-01

    NKT cells are a subgroup of T cells, which express a restricted TCR repertoire and are critical for the innate immune responses to viral infections. Activation of NKT cells depends on the major histocompatibility complex-related molecule CD1d, which presents bioactive lipids to NKT cells. The marine sponge derived lipid αGalCer has recently been demonstrated as a specific agonist for activation of human and murine NKT cells. In the present study we investigated the applicability of αGalCer pre-treatment for immune protection against intra-vaginal HSV-2 infection. We found that C57BL/6 WT mice that received local pre-treatment with αGalCer prior to intra-vaginal HSV-2 infection had a lower mean disease score, mortality and viral load in the vagina following infection, compared to mice that did not receive αGalCer pre-treatment. Further, we found increased numbers of CD45 and NK1.1 positive cells in vaginal tissue and elevated levels of IFN-γ in the vaginal tissue and in vaginal fluids 24h after αGalCer pre-treatment. Collectively our data demonstrate a protective effect of αGalCer induced activation of NKT cells in the innate immune protection against viral infection. PMID:25648689

  7. NKT Cell Immune Responses to Viral Infection

    PubMed Central

    Tessmer, Marlowe S.; Fatima, Ayesha; Paget, Christophe; Trottein, François; Brossay, Laurent

    2010-01-01

    Background Natural killer T (NKT) cells are a heterogeneous population of innate T cells that have attracted recent interest because of their potential to regulate immune responses to a variety of pathogens. The most widely studied NKT cell subset is the invariant (i)NKT cells that recognize glycolipids in the context of the CD1d molecule. The multifaceted methods of activation iNKT cells possess and their ability to produce regulatory cytokines has made them a primary target for therapeutic studies. Objective/Methods This review gives insight into the roles of iNKT cells during infectious diseases, particularly viral infections. We also highlight the different mechanisms leading to iNKT cell activation in response to pathogens. Conclusions The iNKT cell versatility allows them to detect and respond to several viral infections. However, therapeutic approaches to specifically target iNKT cells will require additional research. Notably, examination of the roles of non-invariant NKT cells in response to pathogens warrant further investigations. PMID:19236234

  8. NKAP Regulates Invariant NKT Cell Proliferation and Differentiation into ROR-γt-Expressing NKT17 Cells.

    PubMed

    Thapa, Puspa; Chen, Meibo W; McWilliams, Douglas C; Belmonte, Paul; Constans, Megan; Sant'Angelo, Derek B; Shapiro, Virginia Smith

    2016-06-15

    Invariant NKT (iNKT) cells are a unique lineage with characteristics of both adaptive and innate lymphocytes, and they recognize glycolipids presented by an MHC class I-like CD1d molecule. During thymic development, iNKT cells also differentiate into NKT1, NKT2, and NKT17 functional subsets that preferentially produce cytokines IFN-γ, IL-4, and IL-17, respectively, upon activation. Newly selected iNKT cells undergo a burst of proliferation, which is defective in mice with a specific deletion of NKAP in the iNKT cell lineage, leading to severe reductions in thymic and peripheral iNKT cell numbers. The decreased cell number is not due to defective homeostasis or increased apoptosis, and it is not rescued by Bcl-xL overexpression. NKAP is also required for differentiation into NKT17 cells, but NKT1 and NKT2 cell development and function are unaffected. This failure in NKT17 development is rescued by transgenic expression of promyelocytic leukemia zinc finger; however, the promyelocytic leukemia zinc finger transgene does not restore iNKT cell numbers or the block in positive selection into the iNKT cell lineage in CD4-cre NKAP conditional knockout mice. Therefore, NKAP regulates multiple steps in iNKT cell development and differentiation. PMID:27183586

  9. Circulating Myeloid Dendritic Cells of Advanced Cancer Patients Result in Reduced Activation and a Biased Cytokine Profile in Invariant NKT Cells1

    PubMed Central

    van der Vliet, Hans J. J.; Wang, Ruojie; Yue, Simon C.; Koon, Henry B.; Balk, Steven P.; Exley, Mark A.

    2010-01-01

    CD1d-restricted invariant NKT (iNKT) cells play important regulatory roles in various immune responses, including antitumor immune responses. Previous studies have demonstrated quantitative and qualitative defects in iNKT cells of cancer patients, and these defects are clinically relevant as they are associated with poor prognosis. In this study we demonstrate that defects in the iNKT cell population can, at least in part, be attributed to defective interactions between iNKT cells and CD1d-expressing circulating myeloid dendritic cells (mDC), as mDC of patients with advanced melanoma and renal cell cancer reduced the activation and Th1 cytokine production of healthy donor-derived iNKT cells. Interestingly, this reduced activation of iNKT cells was restricted to patients with low circulating iNKT cell numbers and could be reversed by IL-12 and in part by the neutralization of TGF-β, but it was further reduced by the neutralization of IL-10 in vitro. Additional experiments revealed discordant roles for TGF-β and IL-10 on human iNKT cells, because TGF-β suppressed iNKT cell activation and proliferation and IFN-γ production while IL-10 was identified as a cytokine involved in stimulating the activation and expansion of iNKT cells that could subsequently suppress NK cell and T cell responses. PMID:18490728

  10. Invariant NKT Cell Development Requires a Full Complement of Functional CD3 ζ Immunoreceptor Tyrosine-Based Activation Motifs

    PubMed Central

    Becker, Amy M.; Blevins, Jon S.; Tomson, Farol L.; Eitson, Jennifer L.; Medeiros, Jennifer J.; Yarovinsky, Felix; Norgard, Michael V.; van Oers, Nicolai S. C.

    2010-01-01

    Invariant NKT (iNKT) cells regulate early immune responses to infections, in part because of their rapid release of IFN-γ and IL-4. iNKT cells are proposed to reduce the severity of Lyme disease following Borrelia burgdorferi infection. Unlike conventional T cells, iNKT cells express an invariant αβ TCR that recognizes lipids bound to the MHC class I-like molecule, CD1d. Furthermore, these cells are positively selected following TCR interactions with glycolipid/CD1d complexes expressed on CD4+CD8+ thymocytes. Whereas conventional T cell development can proceed with as few as 4/10 CD3 immunoreceptor tyrosine-based activation motifs (ITAMs), little is known about the ITAM requirements for iNKT cell selection and expansion. We analyzed iNKT cell development in CD3 ζ transgenic lines with various tyrosine-to-phenylalanine substitutions (YF) that eliminated the functions of the first (YF1,2), third (YF5,6), or all three (YF1–6) CD3 ζ ITAMs. iNKT cell numbers were significantly reduced in the thymus, spleen, and liver of all YF mice compared with wild type mice. The reduced numbers of iNKT cells resulted from significant reductions in the expression of the early growth response 2 and promyelocytic leukemia zinc finger transcription factors. In the mice with few to no iNKT cells, there was no difference in the severity of Lyme arthritis compared with wild type controls, following infections with the spirochete B. burgdorferi. These findings indicate that a full complement of functional CD3 ζ ITAMs is required for effective iNKT cell development. The Journal of Immunology, 2010, 184: 6822–6832. PMID:20483726

  11. Cross-Activating Invariant NKT Cells and Kupffer Cells Suppress Cholestatic Liver Injury in a Mouse Model of Biliary Obstruction

    PubMed Central

    Duwaerts, Caroline C.; Sun, Eric P.; Cheng, Chao-Wen; van Rooijen, Nico; Gregory, Stephen H.

    2013-01-01

    Both Kupffer cells and invariant natural killer T (iNKT) cells suppress neutrophil-dependent liver injury in a mouse model of biliary obstruction. We hypothesize that these roles are interdependent and require iNKT cell-Kupffer cell cross-activation. Female, wild-type and iNKT cell-deficient C57Bl/6 mice were injected with magnetic beads 3 days prior to bile duct ligation (BDL) in order to facilitate subsequent Kupffer cell isolation. On day three post-BDL, the animals were euthanized and the livers dissected. Necrosis was scored; Kupffer cells were isolated and cell surface marker expression (flow cytometry), mRNA expression (qtPCR), nitric oxide (NO.) production (Griess reaction), and protein secretion (cytometric bead-array or ELISAs) were determined. To address the potential role of NO. in suppressing neutrophil accumulation, a group of WT mice received 1400W, a specific inducible nitric oxide synthase (iNOS) inhibitor, prior to BDL. To clarify the mechanisms underlying Kupffer cell-iNKT cell cross-activation, WT animals were administered anti-IFN-γ or anti-lymphocyte function-associated antigen (LFA)-1 antibody prior to BDL. Compared to their WT counterparts, Kupffer cells obtained from BDL iNKT cell-deficient mice expressed lower iNOS mRNA levels, produced less NO., and secreted more neutrophil chemoattractants. Both iNOS inhibition and IFN-γ neutralization increased neutrophil accumulation in the livers of BDL WT mice. Anti-LFA-1 pre-treatment reduced iNKT cell accumulation in these same animals. These data indicate that the LFA-1-dependent cross-activation of iNKT cells and Kupffer cells inhibits neutrophil accumulation and cholestatic liver injury. PMID:24260285

  12. Cross-activating invariant NKT cells and kupffer cells suppress cholestatic liver injury in a mouse model of biliary obstruction.

    PubMed

    Duwaerts, Caroline C; Sun, Eric P; Cheng, Chao-Wen; van Rooijen, Nico; Gregory, Stephen H

    2013-01-01

    Both Kupffer cells and invariant natural killer T (iNKT) cells suppress neutrophil-dependent liver injury in a mouse model of biliary obstruction. We hypothesize that these roles are interdependent and require iNKT cell-Kupffer cell cross-activation. Female, wild-type and iNKT cell-deficient C57Bl/6 mice were injected with magnetic beads 3 days prior to bile duct ligation (BDL) in order to facilitate subsequent Kupffer cell isolation. On day three post-BDL, the animals were euthanized and the livers dissected. Necrosis was scored; Kupffer cells were isolated and cell surface marker expression (flow cytometry), mRNA expression (qtPCR), nitric oxide (NO (.) ) production (Griess reaction), and protein secretion (cytometric bead-array or ELISAs) were determined. To address the potential role of NO (.) in suppressing neutrophil accumulation, a group of WT mice received 1400W, a specific inducible nitric oxide synthase (iNOS) inhibitor, prior to BDL. To clarify the mechanisms underlying Kupffer cell-iNKT cell cross-activation, WT animals were administered anti-IFN-γ or anti-lymphocyte function-associated antigen (LFA)-1 antibody prior to BDL. Compared to their WT counterparts, Kupffer cells obtained from BDL iNKT cell-deficient mice expressed lower iNOS mRNA levels, produced less NO (.) , and secreted more neutrophil chemoattractants. Both iNOS inhibition and IFN-γ neutralization increased neutrophil accumulation in the livers of BDL WT mice. Anti-LFA-1 pre-treatment reduced iNKT cell accumulation in these same animals. These data indicate that the LFA-1-dependent cross-activation of iNKT cells and Kupffer cells inhibits neutrophil accumulation and cholestatic liver injury. PMID:24260285

  13. Invariant NKT Cell Activation Induces Late Preterm Birth That Is Attenuated by Rosiglitazone.

    PubMed

    St Louis, Derek; Romero, Roberto; Plazyo, Olesya; Arenas-Hernandez, Marcia; Panaitescu, Bogdan; Xu, Yi; Milovic, Tatjana; Xu, Zhonghui; Bhatti, Gaurav; Mi, Qing-Sheng; Drewlo, Sascha; Tarca, Adi L; Hassan, Sonia S; Gomez-Lopez, Nardhy

    2016-02-01

    Preterm birth (PTB) is the leading cause of neonatal morbidity and mortality worldwide. Although intra-amniotic infection is a recognized cause of spontaneous preterm labor, the noninfection-related etiologies are poorly understood. In this article, we demonstrated that the expansion of activated CD1d-restricted invariant NKT (iNKT) cells in the third trimester by administration of α-galactosylceramide (α-GalCer) induced late PTB and neonatal mortality. In vivo imaging revealed that fetuses from mice that underwent α-GalCer-induced late PTB had bradycardia and died shortly after delivery. Yet, administration of α-GalCer in the second trimester did not cause pregnancy loss. Peroxisome proliferator-activated receptor (PPAR)γ activation, through rosiglitazone treatment, reduced the rate of α-GalCer-induced late PTB and improved neonatal survival. Administration of α-GalCer in the third trimester suppressed PPARγ activation, as shown by the downregulation of Fabp4 and Fatp4 in myometrial and decidual tissues, respectively; this suppression was rescued by rosiglitazone treatment. Administration of α-GalCer in the third trimester induced an increase in the activation of conventional CD4(+) T cells in myometrial tissues and the infiltration of activated macrophages, neutrophils, and mature dendritic cells to myometrial and/or decidual tissues. All of these effects were blunted after rosiglitazone treatment. Administration of α-GalCer also upregulated the expression of inflammatory genes at the maternal-fetal interface and systemically, and rosiglitazone treatment partially attenuated these responses. Finally, an increased infiltration of activated iNKT-like cells in human decidual tissues is associated with noninfection-related preterm labor/birth. Collectively, these results demonstrate that iNKT cell activation in vivo leads to late PTB by initiating innate and adaptive immune responses and suggest that the PPARγ pathway has potential as a target for

  14. CD252 regulates mast cell mediated, CD1d-restricted NKT-cell activation in mice.

    PubMed

    Gonzalez Roldan, Nestor; Orinska, Zane; Ewers, Hanno; Bulfone-Paus, Silvia

    2016-02-01

    The interaction between tissue-resident mast cells (MCs) and recruited immune cells contributes to tissue immunosurveillance. However, the cells, mechanisms, and receptors involved in this crosstalk remain ill defined. Invariant natural killer T (iNKT) cells are CD1d-restricted innate lymphocytes that recognize glycolipid antigens and have emerged as critical players in immunity. Here, we show that primary mouse peritoneal MCs express surface CD1d, which is upregulated in vivo following administration of alpha-galactosylceramide. In contrast, in BM-derived MCs CD1d was found to be stored intracellularly and to relocate at the cell surface upon IgE-mediated degranulation. Activated BM-derived MCs expressing surface CD1d and loaded with alpha-galactosylceramide were found to induce iNKT-cell proliferation and the release of IFN-γ, IL-13, and IL-4 in a CD1d-restricted manner. Moreover, the costimulatory molecules CD48, CD137L, CD252, CD274, and CD275 affected MC-induced IFN-γ release and iNKT-cell proliferation. Interestingly, among the costimulatory molecules, CD48 and CD252 exhibited a distinctly regulatory activity on iNKT-cell release of both IFN-γ and IL-13. In conclusion, we demonstrate that the crosstalk between MCs and iNKT cells may regulate inflammatory immune responses. PMID:26564814

  15. CD62L+ NKT cells have prolonged persistence and antitumor activity in vivo

    PubMed Central

    Tian, Gengwen; Courtney, Amy N.; Jena, Bipulendu; Heczey, Andras; Liu, Daofeng; Marinova, Ekaterina; Guo, Linjie; Xu, Xin; Torikai, Hiroki; Mo, Qianxing; Dotti, Gianpietro; Cooper, Laurence J.; Metelitsa, Leonid S.

    2016-01-01

    Vα24-invariant natural killer T cells (NKTs) localize to tumors and have inherent antitumor properties, making them attractive chimeric antigen receptor (CAR) carriers for redirected cancer immunotherapy. However, clinical application of CAR-NKTs has been impeded, as mechanisms responsible for NKT expansion and the in vivo persistence of these cells are unknown. Here, we demonstrated that antigen-induced expansion of primary NKTs in vitro associates with the accumulation of a CD62L+ subset and exhaustion of CD62L– cells. Only CD62L+ NKTs survived and proliferated in response to secondary stimulation. When transferred to immune-deficient NSG mice, CD62L+ NKTs persisted 5 times longer than CD62L– NKTs. Moreover, CD62L+ cells transduced with a CD19-specific CAR achieved sustained tumor regression in a B cell lymphoma model. Proliferating CD62L+ cells downregulated or maintained CD62L expression when activated via T cell receptor alone or in combination with costimulatory receptors. We generated HLAnull K562 cell clones that were engineered to express CD1d and costimulatory ligands. Clone B-8-2 (HLAnullCD1dmedCD86high4-1BBLmedOX40Lhigh) induced the highest rates of NKT expansion and CD62L expression. B-8-2–expanded CAR-NKTs exhibited prolonged in vivo persistence and superior therapeutic activities in models of lymphoma and neuroblastoma. Therefore, we have identified CD62L as a marker of a distinct NKT subset endowed with high proliferative potential and have developed artificial antigen-presenting cells that generate CD62L-enriched NKTs for effective cancer immunotherapy. PMID:27183388

  16. CD62L+ NKT cells have prolonged persistence and antitumor activity in vivo.

    PubMed

    Tian, Gengwen; Courtney, Amy N; Jena, Bipulendu; Heczey, Andras; Liu, Daofeng; Marinova, Ekaterina; Guo, Linjie; Xu, Xin; Torikai, Hiroki; Mo, Qianxing; Dotti, Gianpietro; Cooper, Laurence J; Metelitsa, Leonid S

    2016-06-01

    Vα24-invariant natural killer T cells (NKTs) localize to tumors and have inherent antitumor properties, making them attractive chimeric antigen receptor (CAR) carriers for redirected cancer immunotherapy. However, clinical application of CAR-NKTs has been impeded, as mechanisms responsible for NKT expansion and the in vivo persistence of these cells are unknown. Here, we demonstrated that antigen-induced expansion of primary NKTs in vitro associates with the accumulation of a CD62L+ subset and exhaustion of CD62L- cells. Only CD62L+ NKTs survived and proliferated in response to secondary stimulation. When transferred to immune-deficient NSG mice, CD62L+ NKTs persisted 5 times longer than CD62L- NKTs. Moreover, CD62L+ cells transduced with a CD19-specific CAR achieved sustained tumor regression in a B cell lymphoma model. Proliferating CD62L+ cells downregulated or maintained CD62L expression when activated via T cell receptor alone or in combination with costimulatory receptors. We generated HLAnull K562 cell clones that were engineered to express CD1d and costimulatory ligands. Clone B-8-2 (HLAnullCD1dmedCD86high4-1BBLmedOX40Lhigh) induced the highest rates of NKT expansion and CD62L expression. B-8-2-expanded CAR-NKTs exhibited prolonged in vivo persistence and superior therapeutic activities in models of lymphoma and neuroblastoma. Therefore, we have identified CD62L as a marker of a distinct NKT subset endowed with high proliferative potential and have developed artificial antigen-presenting cells that generate CD62L-enriched NKTs for effective cancer immunotherapy. PMID:27183388

  17. Generation of Human iNKT Cell Lines

    PubMed Central

    Li, Xiangming; Tsuji, Moriya; Schneck, Jonathan; Webb, Tonya J.

    2016-01-01

    Natural killer T (NKT) cells comprise an important immunoregulatory T cell subset and express cell surface proteins characteristic of both natural killer cells and T cells. Invariant NKT (iNKT) cells are activated by lipid antigen presented in the context of CD1d molecules, in contrast to classic T cell subsets, which recognize peptide antigens presented by MHC molecules. Following activation, iNKT cells rapidly secrete large amounts of cytokines and can lyse tumor cells and virally infected cells; however, iNKT cells are reduced in patients with autoimmune disease and cancer. The potential to characterize and investigate the prospective use of iNKT cells for therapeutic purposes has significantly increased with the ability to stimulate and expand human iNKT cells. In this protocol, we describe a method to generate and propagate primary human iNKT cells. Specifically, primary iNKT cells were isolated from human peripheral blood mononuclear cells (PBMC), and then expanded periodically with irradiated α-GalCer loaded autologous immature dendritic cells (DC) in the presence of human IL-2.

  18. NF-κB Is Activated in CD4+ iNKT Cells by Sickle Cell Disease and Mediates Rapid Induction of Adenosine A2A Receptors

    PubMed Central

    Yu, Jennifer C.; Ken, Ruey; Neuberg, Donna; Nathan, David G.; Linden, Joel

    2013-01-01

    Reperfusion injury following tissue ischemia occurs as a consequence of vaso-occlusion that is initiated by activation of invariant natural killer T (iNKT) cells. Sickle cell disease (SDC) results in widely disseminated microvascular ischemia and reperfusion injury as a result of vaso-occlusion by rigid and adhesive sickle red blood cells. In mice, iNKT cell activation requires NF-κB signaling and can be inhibited by the activation of anti-inflammatory adenosine A2A receptors (A2ARs). Human iNKT cells are divided into subsets of CD4+ and CD4- cells. In this study we found that human CD4+ iNKT cells, but not CD4- cells undergo rapid NF-κB activation (phosphorylation of NF-κB on p65) and induction of A2ARs (detected with a monoclonal antibody 7F6-G5-A2) during SCD painful vaso-occlusive crises. These findings indicate that SCD primarily activates the CD4+ subset of iNKT cells. Activation of NF-κB and induction of A2ARs is concordant, i.e. only CD4+ iNKT cells with activated NF-κB expressed high levels of A2ARs. iNKT cells that are not activated during pVOC express low levels of A2AR immunoreactivity. These finding suggest that A2AR transcription may be induced in CD4+ iNKT cells as a result of NF-κB activation in SCD. In order to test this hypothesis further we examined cultured human iNKT cells. In cultured cells, blockade of NF-κB with Bay 11–7082 or IKK inhibitor VII prevented rapid induction of A2AR mRNA and protein upon iNKT activation. In conclusion, NF-κB-mediated induction of A2ARs in iNKT cells may serve as a counter-regulatory mechanism to limit the extent and duration of inflammatory immune responses. As activated iNKT cells express high levels of A2ARs following their activation, they may become highly sensitive to inhibition by A2AR agonists. PMID:24124453

  19. The actin cytoskeleton modulates the activation of iNKT cells by segregating CD1d nanoclusters on antigen-presenting cells

    PubMed Central

    Torreno-Pina, Juan A.; Manzo, Carlo; Salio, Mariolina; Aichinger, Michael C.; Oddone, Anna; Lakadamyali, Melike; Shepherd, Dawn; Besra, Gurdyal S.; Cerundolo, Vincenzo

    2016-01-01

    Invariant natural killer T (iNKT) cells recognize endogenous and exogenous lipid antigens presented in the context of CD1d molecules. The ability of iNKT cells to recognize endogenous antigens represents a distinct immune recognition strategy, which underscores the constitutive memory phenotype of iNKT cells and their activation during inflammatory conditions. However, the mechanisms regulating such “tonic” activation of iNKT cells remain unclear. Here, we show that the spatiotemporal distribution of CD1d molecules on the surface of antigen-presenting cells (APCs) modulates activation of iNKT cells. By using superresolution microscopy, we show that CD1d molecules form nanoclusters at the cell surface of APCs, and their size and density are constrained by the actin cytoskeleton. Dual-color single-particle tracking revealed that diffusing CD1d nanoclusters are actively arrested by the actin cytoskeleton, preventing their further coalescence. Formation of larger nanoclusters occurs in the absence of interactions between CD1d cytosolic tail and the actin cytoskeleton and correlates with enhanced iNKT cell activation. Importantly and consistently with iNKT cell activation during inflammatory conditions, exposure of APCs to the Toll-like receptor 7/8 agonist R848 increases nanocluster density and iNKT cell activation. Overall, these results define a previously unidentified mechanism that modulates iNKT cell autoreactivity based on the tight control by the APC cytoskeleton of the sizes and densities of endogenous antigen-loaded CD1d nanoclusters. PMID:26798067

  20. The actin cytoskeleton modulates the activation of iNKT cells by segregating CD1d nanoclusters on antigen-presenting cells.

    PubMed

    Torreno-Pina, Juan A; Manzo, Carlo; Salio, Mariolina; Aichinger, Michael C; Oddone, Anna; Lakadamyali, Melike; Shepherd, Dawn; Besra, Gurdyal S; Cerundolo, Vincenzo; Garcia-Parajo, Maria F

    2016-02-01

    Invariant natural killer T (iNKT) cells recognize endogenous and exogenous lipid antigens presented in the context of CD1d molecules. The ability of iNKT cells to recognize endogenous antigens represents a distinct immune recognition strategy, which underscores the constitutive memory phenotype of iNKT cells and their activation during inflammatory conditions. However, the mechanisms regulating such "tonic" activation of iNKT cells remain unclear. Here, we show that the spatiotemporal distribution of CD1d molecules on the surface of antigen-presenting cells (APCs) modulates activation of iNKT cells. By using superresolution microscopy, we show that CD1d molecules form nanoclusters at the cell surface of APCs, and their size and density are constrained by the actin cytoskeleton. Dual-color single-particle tracking revealed that diffusing CD1d nanoclusters are actively arrested by the actin cytoskeleton, preventing their further coalescence. Formation of larger nanoclusters occurs in the absence of interactions between CD1d cytosolic tail and the actin cytoskeleton and correlates with enhanced iNKT cell activation. Importantly and consistently with iNKT cell activation during inflammatory conditions, exposure of APCs to the Toll-like receptor 7/8 agonist R848 increases nanocluster density and iNKT cell activation. Overall, these results define a previously unidentified mechanism that modulates iNKT cell autoreactivity based on the tight control by the APC cytoskeleton of the sizes and densities of endogenous antigen-loaded CD1d nanoclusters. PMID:26798067

  1. Vα24-invariant NKT cells mediate antitumor activity via killing of tumor-associated macrophages

    PubMed Central

    Song, Liping; Asgharzadeh, Shahab; Salo, Jill; Engell, Kelly; Wu, Hong-wei; Sposto, Richard; Ara, Tasnim; Silverman, Ayaka M.; DeClerck, Yves A.; Seeger, Robert C.; Metelitsa, Leonid S.

    2009-01-01

    Tumor infiltration with Vα24-invariant NKT cells (NKTs) associates with favorable outcome in neuroblastoma and other cancers. Although NKTs can be directly cytotoxic against CD1d+ cells, the majority of human tumors are CD1d–. Therefore, the role of NKTs in cancer remains largely unknown. Here, we demonstrate that CD68+ tumor-associated monocytes/macrophages (TAMs) represented the majority of CD1d-expressing cells in primary human neuroblastomas. TAMs stimulated neuroblastoma growth in human cell lines and their xenografts in NOD/SCID mice via IL-6 production. Indeed, TAMs produced IL-6 in primary tumors and in the BM of patients with metastatic neuroblastoma. Gene expression analysis using TaqMan low-density arrays of 129 primary human neuroblastomas without MYCN amplification revealed that high-level expression of TAM-specific genes (CD14, CD16, IL6, IL6R, and TGFB1) was associated with poor 5-year event-free survival. While NKTs were not cytotoxic against neuroblastoma cells, they effectively killed monocytes pulsed with tumor cell lysate. The killing of monocytes was CD1d restricted because it was inhibited by a CD1d-specific mAb. Cotransfer of human monocytes and NKTs to tumor-bearing NOD/SCID mice decreased monocyte number at the tumor site and suppressed tumor growth compared with mice transferred with monocytes alone. Thus, killing of TAMs reveals what we believe to be a novel mechanism of NKT antitumor activity that relates to the disease outcome. PMID:19411762

  2. [NKT cells: their development, mechanisms and effects of action].

    PubMed

    Bojarska-Junak, Agnieszka; Tabarkiewicz, Jacek; Roliński, Jacek

    2013-01-01

    NKT cells are a heterogeneous 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 semi-invariant T cell receptor that reacts with glycolipid antigens presented by the CD1d molecule on the surface of antigen-presenting cells. NKT cells can modulate the immune response against infectious agents, autoantigens, tumors, tissue grafts and allergens. NKT cells mediate the activities through their ability to express pro- and anti-inflammatory cytokines that influence the type and magnitude of the immune response. The manuscript summarizes current views on development of NKT cells as well as mechanisms and effects of their action.  PMID:23475484

  3. α-Galactosylceramide-activated murine NK1.1(+) invariant-NKT cells in the myometrium induce miscarriages in mice.

    PubMed

    Ichikawa, Tomoko; Negishi, Yasuyuki; Shimizu, Masumi; Takeshita, Toshiyuki; Takahashi, Hidemi

    2016-08-01

    Innate immunity, which is unable to discriminate self from allo-antigens, is thought to be important players in the induction of miscarriages. Here, we show that the administration of IL-12 to syngeneic-mated C57BL/6 mice on gestation day 7.5 (Gd 7.5), drives significant miscarriages in pregnant females. Furthermore, the administration on Gd 7.5 of α-galactosylceramide (α-GalCer), which is known to activate invariant natural killer T (iNKT) cells, induced miscarriages in both syngeneic-mated C57BL/6 mice and allogeneic-mated mice (C57BL/6 (♀) × BALB/c (♂)). Surprisingly, the percentages of both DEC-205(+) DCs and CD1d-restricted NK1.1(+) iNKT cells were higher in the myometrium of pregnant mice treated i.p. with α-GalCer than in the decidua. IL-12 secreted from α-GalCer-activated DEC-205(+) DCs stimulated the secretion of cytokines, including IL-2, IL-4, IFN-γ, TNF-α, perforin, and granzyme B, from the NK1.1(+) iNKT cells in the myometrium, leading to fetal loss in pregnant mice. Finally, the i.p. administration of IL-12 and/or α-GalCer in iNKT-deficient Jα18(-/-) (Jα18 KO) mice did not induce miscarriages. This study provides a new perspective on the importance of the myometrium, rather than the decidua, in regulating pregnancy and a mechanism of miscarriage mediated by activated DEC-205(+) DCs and NK1.1(+) iNKT cells in the myometrium of pregnant mice. PMID:27198610

  4. Control of NKT cell differentiation by tissue-specific microenvironments.

    PubMed

    Yang, Yang; Ueno, Aito; Bao, Min; Wang, Zhongying; Im, Jin Seon; Porcelli, Steven; Yoon, Ji-Won

    2003-12-01

    CD1d-restricted Valpha14 NKT cells play an important role in both Th1- and Th2-type immune responses. To determine whether NKT cells develop two functionally distinct subsets that provoke different types of responses, we examined the phenotypes and cellular functions of NK1.1(+) and DX5(+) T cells. We found that both NK1.1(+) and DX5(+) T cells are CD1d-restricted Valpha14 T cells with identical Ag specificities, phenotypes, tissue locations, and functions. Similar to the NK1.1 marker, the DX5 marker (CD49b) is expressed on mature NKT cells in both NK1.1 allele-positive and allele-negative strains. However, when NK1.1(+) and DX5(+) NKT cells isolated from different tissues were compared, we found that thymic and splenic NKT cells differed not only in their cytokine profiles, but also in their phenotype and requirements for costimulatory signals. Thymic NKT cells displayed the phenotype of activated T cells and could be fully activated by TCR ligation. In contrast, splenic NKT cells displayed the phenotype of memory T cells and required a costimulatory signal for activation. Furthermore, the function and phenotype of thymic and splenic NKT cells were modulated by APCs from various tissues that expressed different levels of costimulatory molecules. Modulation of NKT cell function and differentiation may be mediated by synergic effects of costimulatory molecules on the surface of APCs. The results of the present study suggest that the costimulatory signals of tissue-specific APCs are key factors for NKT cell differentiation, and these signals cannot be replaced by anti-CD28 or anti-CD40 ligand Abs. PMID:14634102

  5. Regulation of NKT Cell Localization in Homeostasis and Infection

    PubMed Central

    Slauenwhite, Drew; Johnston, Brent

    2015-01-01

    Natural killer T (NKT) cells are a specialized subset of T lymphocytes that regulate immune responses in the context of autoimmunity, cancer, and microbial infection. Lipid antigens derived from bacteria, parasites, and fungi can be presented by CD1d molecules and recognized by the canonical T cell receptors on NKT cells. Alternatively, NKT cells can be activated through recognition of self-lipids and/or pro-inflammatory cytokines generated during infection. Unlike conventional T cells, only a small subset of NKT cells traffic through the lymph nodes under homeostatic conditions, with the largest NKT cell populations localizing to the liver, lungs, spleen, and bone marrow. This is thought to be mediated by differences in chemokine receptor expression profiles. However, the impact of infection on the tissue localization and function of NKT remains largely unstudied. This review focuses on the mechanisms mediating the establishment of peripheral NKT cell populations during homeostasis and how tissue localization of NKT cells is affected during infection. PMID:26074921

  6. The Transcriptional Repressor Gfi1 Plays a Critical Role in the Development of NKT1- and NKT2-Type iNKT Cells

    PubMed Central

    Yasuoka, Toshiaki; Kuwahara, Makoto; Yamada, Takeshi; Maruyama, Saho; Suzuki, Junpei; Taniguchi, Masaru; Yasukawa, Masaki; Yamashita, Masakatsu

    2016-01-01

    Gfi1 plays an important role in the development and maintenance of many hematopoietic linage cells. However, the impact of Gfi1-deficiency on the iNKT cell differentiation remains unclear. We herein demonstrate a critical role of Gfi1 in regulating the development of iNKT cell subsets. In the thymus of T cell-specific Gfi1-deficient mice, iNKT cells normally developed up to stage 2, while the number of stage 3 NK1.1pos iNKT cells was significantly reduced. Furthermore, CD4pos iNKT cells were selectively reduced in the peripheral organs of T cell-specific Gfi1-deficient mice. The α-GalCer-dependent production of IFN-γand Th2 cytokines, but not IL-17A, was severely reduced in T cell-specific Gfi1-deficient mice. In addition, a reduction of the α-GalCer-induced anti-tumor activity was observed in Gfi1-deficient mice. These findings demonstrate the important role of Gfi1 in regulating the development and function of NKT1- and NKT2-type iNKT cell subsets. PMID:27284976

  7. Discovery of NKT cells and development of NKT cell-targeted anti-tumor immunotherapy

    PubMed Central

    TANIGUCHI, Masaru; HARADA, Michishige; DASHTSOODOL, Nyambayar; KOJO, Satoshi

    2015-01-01

    Natural Killer T (NKT) cells are unique lymphocytes characterized by their expression of a single invariant antigen receptor encoded by Vα14Jα18 in mice and Vα24Jα18 in humans, which recognizes glycolipid antigens in association with the monomorphic CD1d molecule. NKT cells mediate adjuvant activity to activate both CD8T cells to kill MHC-positive tumor cells and NK cells to eliminate MHC-negative tumor at the same time in patients, resulting in the complete eradication of tumors without relapse. Therefore, the NKT cell-targeted therapy can be applied to any type of tumor and also to anyone individual, regardless of HLA type. Phase IIa clinical trials on advanced lung cancers and head and neck tumors have been completed and showed significantly prolonged median survival times with only the primary treatment. Another potential treatment option for the future is to use induced pluripotent stem cell (iPS)-derived NKT cells, which induced adjuvant effects on anti-tumor responses, inhibiting in vivo tumor growth in a mouse model. PMID:26194854

  8. Sickle cell vaso-occlusion causes activation of iNKT cells that is decreased by the adenosine A2A receptor agonist regadenoson

    PubMed Central

    Lin, Gene; Okam, Maureen M.; Majerus, Elaine; Keefer, Jeffrey; Onyekwere, Onyinye; Ross, Ainsley; Campigotto, Federico; Neuberg, Donna; Linden, Joel; Nathan, David G.

    2013-01-01

    Adenosine A2A receptor (A2AR) agonists reduce invariant natural killer T (iNKT) cell activation and decrease inflammation in sickle cell disease (SCD) mice. We conducted a phase 1 trial of the A2AR agonist regadenoson in adults with SCD. The target dose was 1.44 μg/kg/h. iNKT cell activation was evaluated using antibodies targeting the p65 subunit of nuclear factor-κB (phospho-NF-κB p65), interferon-γ (IFN-γ), and A2AR. Regadenoson was administered to 27 adults with SCD. We examined 21 patients at steady state and 6 during painful vaso-occlusive crises (pVOC). iNKT cell activation was also measured in 14 African-American controls. During pVOC, the fraction of iNKT cells demonstrating increased phospho-NF-κB p65 and A2AR expression was significantly higher compared with controls (P < .01) and steady-state patients (P < .05). IFN-γ expression was also significantly higher compared with controls (P = .02). After a 24-hour infusion of regadenoson during pVOC, phospho-NF-κB p65 activation in iNKT cells decreased compared to baseline by a median of 48% (P = .03) to levels similar to controls and steady-state SCD. No toxicities were identified. Infusional regadenoson administered to adults with SCD at 1.44 μg/kg/h during pVOC decreases activation of iNKT cells without toxicity. This trial was registered at www.clinicaltrials.gov as #NCT01085201. PMID:23377438

  9. Mouse Invariant Monoclonal Antibody NKT14: A Novel Tool to Manipulate iNKT Cell Function In Vivo

    PubMed Central

    Scheuplein, Felix; Lamont, Deanna J.; Poynter, Matthew E.; Boyson, Jonathan E.; Serreze, David; Lundblad, Lennart K. A.; Mashal, Robert; Schaub, Robert

    2015-01-01

    Invariant Natural Killer T (iNKT) cells are a T cell subset expressing an invariant T Cell Receptor (TCR) that recognizes glycolipid antigens rather than peptides. The cells have both innate-like rapid cytokine release, and adaptive-like thymic positive selection. iNKT cell activation has been implicated in the pathogenesis of allergic asthma and inflammatory diseases, while reduced iNKT cell activation promotes infectious disease, cancer and certain autoimmune diseases such as Type 1 diabetes (T1D). Therapeutic means to reduce or deplete iNKT cells could treat inflammatory diseases, while approaches to promote their activation may have potential in certain infectious diseases, cancer or autoimmunity. Thus, we developed invariant TCR-specific monoclonal antibodies to better understand the role of iNKT cells in disease. We report here the first monoclonal antibodies specific for the mouse invariant TCR that by modifying the Fc construct can specifically deplete or activate iNKT cells in vivo in otherwise fully immuno-competent animals. We have used both the depleting and activating version of the antibody in the NOD model of T1D. As demonstrated previously using genetically iNKT cell deficient NOD mice, and in studies of glycolipid antigen activated iNKT cells in standard NOD mice, we found that antibody mediated depletion or activation of iNKT cells respectively accelerated and retarded T1D onset. In BALB/c mice, ovalbumin (OVA) mediated airway hyper-reactivity (AHR) was abrogated with iNKT cell depletion prior to OVA sensitization, confirming studies in knockout mice. Depletion of iNKT cells after sensitization had no effect on AHR in the conducting airways but did reduce AHR in the lung periphery. This result raises caution in the interpretation of studies that use animals that are genetically iNKT cell deficient from birth. These activating and depleting antibodies provide a novel tool to assess the therapeutic potential of iNKT cell manipulation. PMID:26474487

  10. NK/T cell lymphoma associated with peripheral eosinophilia.

    PubMed

    Yap, E; Wan Jamaluddin, W F; Tumian, N R; Mashuri, F; Mohammed, F; Tan, G C; Masir, N; Abdul Wahid, F S

    2014-12-01

    NK/T cell lymphoma, nasal type is an aggressive and uncommon malignancy. Disease that occurs outside of the aerodigestive tract exhibits an even more aggressive clinical behaviour and does not respond as well to conventional therapy compared to its nasal counterpart. We report such a case of NK/T cell lymphoma, nasal type, that presented as an anterior chest wall mass, arising from the left pectoralis muscle. An interesting feature we wish to highlight is the associated eosinophilia that corresponded to disease activity, exhibiting fluctuations with surgical resection and chemotherapy. To the best of our knowledge this is the third reported case of NK/T cell lymphoma that is associated with peripheral eosinophilia. Our case highlights the role of certain NK cell subsets that play a major role in eosinophilic activation in NK/T lymphomas and calls for more research into further classification of this disease by virtue of its NK cell subsets. PMID:25500520

  11. NK-, NKT- and CD8-Derived IFNγ Drives Myeloid Cell Activation and Erythrophagocytosis, Resulting in Trypanosomosis-Associated Acute Anemia.

    PubMed

    Cnops, Jennifer; De Trez, Carl; Stijlemans, Benoit; Keirsse, Jiri; Kauffmann, Florence; Barkhuizen, Mark; Keeton, Roanne; Boon, Louis; Brombacher, Frank; Magez, Stefan

    2015-06-01

    African trypanosomes are the causative agents of Human African Trypanosomosis (HAT/Sleeping Sickness) and Animal African Trypanosomosis (AAT/Nagana). A common hallmark of African trypanosome infections is inflammation. In murine trypanosomosis, the onset of inflammation occurs rapidly after infection and is manifested by an influx of myeloid cells in both liver and spleen, accompanied by a burst of serum pro-inflammatory cytokines. Within 48 hours after reaching peak parasitemia, acute anemia develops and the percentage of red blood cells drops by 50%. Using a newly developed in vivo erythrophagocytosis assay, we recently demonstrated that activated cells of the myeloid phagocytic system display enhanced erythrophagocytosis causing acute anemia. Here, we aimed to elucidate the mechanism and immune pathway behind this phenomenon in a murine model for trypanosomosis. Results indicate that IFNγ plays a crucial role in the recruitment and activation of erythrophagocytic myeloid cells, as mice lacking the IFNγ receptor were partially protected against trypanosomosis-associated inflammation and acute anemia. NK and NKT cells were the earliest source of IFNγ during T. b. brucei infection. Later in infection, CD8+ and to a lesser extent CD4+ T cells become the main IFNγ producers. Cell depletion and transfer experiments indicated that during infection the absence of NK, NKT and CD8+ T cells, but not CD4+ T cells, resulted in a reduced anemic phenotype similar to trypanosome infected IFNγR-/- mice. Collectively, this study shows that NK, NKT and CD8+ T cell-derived IFNγ is a critical mediator in trypanosomosis-associated pathology, driving enhanced erythrophagocytosis by myeloid phagocytic cells and the induction of acute inflammation-associated anemia. PMID:26070118

  12. NK-, NKT- and CD8-Derived IFNγ Drives Myeloid Cell Activation and Erythrophagocytosis, Resulting in Trypanosomosis-Associated Acute Anemia

    PubMed Central

    Cnops, Jennifer; De Trez, Carl; Stijlemans, Benoit; Keirsse, Jiri; Kauffmann, Florence; Barkhuizen, Mark; Keeton, Roanne; Boon, Louis; Brombacher, Frank; Magez, Stefan

    2015-01-01

    African trypanosomes are the causative agents of Human African Trypanosomosis (HAT/Sleeping Sickness) and Animal African Trypanosomosis (AAT/Nagana). A common hallmark of African trypanosome infections is inflammation. In murine trypanosomosis, the onset of inflammation occurs rapidly after infection and is manifested by an influx of myeloid cells in both liver and spleen, accompanied by a burst of serum pro-inflammatory cytokines. Within 48 hours after reaching peak parasitemia, acute anemia develops and the percentage of red blood cells drops by 50%. Using a newly developed in vivo erythrophagocytosis assay, we recently demonstrated that activated cells of the myeloid phagocytic system display enhanced erythrophagocytosis causing acute anemia. Here, we aimed to elucidate the mechanism and immune pathway behind this phenomenon in a murine model for trypanosomosis. Results indicate that IFNγ plays a crucial role in the recruitment and activation of erythrophagocytic myeloid cells, as mice lacking the IFNγ receptor were partially protected against trypanosomosis-associated inflammation and acute anemia. NK and NKT cells were the earliest source of IFNγ during T. b. brucei infection. Later in infection, CD8+ and to a lesser extent CD4+ T cells become the main IFNγ producers. Cell depletion and transfer experiments indicated that during infection the absence of NK, NKT and CD8+ T cells, but not CD4+ T cells, resulted in a reduced anemic phenotype similar to trypanosome infected IFNγR-/- mice. Collectively, this study shows that NK, NKT and CD8+ T cell-derived IFNγ is a critical mediator in trypanosomosis-associated pathology, driving enhanced erythrophagocytosis by myeloid phagocytic cells and the induction of acute inflammation-associated anemia. PMID:26070118

  13. NKG2D performs two functions in invariant NKT cells: Direct TCR-independent activation of NK-like cytolysis, and co-stimulation of activation by CD1d

    PubMed Central

    Kuylenstierna, Carlotta; Björkström, Niklas K.; Andersson, Sofia K.; Sahlström, Peter; Bosnjak, Lidija; Paquin-Proulx, Dominic; Malmberg, Karl-Johan; Ljunggren, Hans-Gustaf; Moll, Markus; Sandberg, Johan K.

    2012-01-01

    Invariant NKT cells are important in the activation and regulation of immune responses. They can also function as CD1d-restricted killer cells. However, the role of activating innate NK cell receptors expressed on NKT cells in triggering cytolytic function is poorly characterized. Here, we initially confirmed that the cellular stress-ligand receptor NKG2D is expressed on CD4− NKT cells, whereas most CD4+ NKT cells lack this receptor. Interestingly, NKG2D+ NKT cells frequently expressed perforin, and both NKG2D and perforin localized at the site of contact with NKG2D ligand-expressing target cells. CD4− NKT cells degranulated in response to NKG2D engagement in a redirected activation assay independently of stimulation via their invariant TCR. NKT cells killed P815 cells coated with anti-NKG2D mAb and CD1d-negative K562 tumor target cells in an NKG2D-dependent manner. Furthermore, NKG2D engagement co-stimulated TCR-mediated NKT cell activation in response to endogenous CD1d-presented ligands or suboptimal levels of anti-CD3 triggering. These data indicate that the CD4− subset of human NKT cells can mediate direct lysis of target cells via NKG2D engagement independently of CD1d, and that NKG2D also functions as a co-stimulatory receptor in these cells. NKG2D thus plays both a direct and a co-stimulatory role in the activation of NKT cells. PMID:21590763

  14. Rapid NKT cell responses are self-terminating during the course of microbial infection.

    PubMed

    Chiba, Asako; Dascher, Christopher C; Besra, Gurdal S; Brenner, Michael B

    2008-08-15

    NKT cells play a protective role in immune responses against infectious pathogens. However, when the NKT cell response to infection is initiated and terminated is unknown. In this study, we demonstrate that NKT cells become activated, proliferate, and exert their effector function before MHC-restricted T cells during infection with Mycobacterium bovis bacillus Calmette-Guérin in mice. After a cell expansion phase, NKT cells underwent cell death, which contracts their numbers back to baseline. Surprisingly, despite ongoing infection, the remaining NKT cells were profoundly unresponsive to TCR stimulation, while MHC-restricted T cells were vigorously proliferating and producing IFN-gamma. Similarly, we show that NKT cells became unresponsive in uninfected mice after receiving a single exposure to a TLR agonist LPS, suggesting that NKT cell unresponsiveness may be a major mechanism of terminating their response in many infectious conditions. This characterization of the NKT cell response in antimicrobial immunity indicates that rapid NKT cell activation contributes to the innate phase of the response to the infectious pathogen, but then, the NKT cell response is shut down by two mechanisms; apoptotic contraction and marked unresponsiveness to TCR stimulation, as a synchronized hand off to MHC-restricted T cells occurs. PMID:18684918

  15. Invariant NKT cells provide innate and adaptive help for B cells.

    PubMed

    Vomhof-DeKrey, Emilie E; Yates, Jennifer; Leadbetter, Elizabeth A

    2014-06-01

    B cells rely on CD4(+) T cells helper signals to optimize their responses to T-dependent antigens. Recently another subset of T cells has been identified which provides help for B cells, invariant natural killer T (iNKT) cells. iNKT cells are unique because they provide both innate and adaptive forms of help to B cells, with divergent outcomes. iNKT cells are widely distributed throughout the spleen at rest, consolidate in the marginal zone of the spleen early after activation, and are later found in germinal centers. Understanding the activation requirements for iNKT cells has led to the development of glycolipid containing nanoparticles which efficiently activate iNKT cells, enhance their cooperation with B cells, and which hold promise for vaccine development. PMID:24514004

  16. Fructose-induced steatosis in mice: role of plasminogen activator inhibitor-1, microsomal triglyceride transfer protein and NKT cells.

    PubMed

    Kanuri, Giridhar; Spruss, Astrid; Wagnerberger, Sabine; Bischoff, Stephan C; Bergheim, Ina

    2011-06-01

    Plasminogen activator inhibitor-1 (PAI-1) is an acute-phase protein known to be involved in alcoholic liver disease and hepatic fibrosis. In the present study, the hypothesis that PAI-1 is causally involved in the onset of fructose-induced hepatic steatosis was tested in a mouse model. Wild-type C57BL/6J and PAI-1⁻/⁻ mice were fed with 30% fructose solution or water for 8 weeks. Markers of hepatic steatosis, expression of PAI-1, apolipoprotein B (ApoB), cluster of differentiation 1d (CD1d), markers of natural killer T (NKT) cells, protein levels of phospho-c-Met and tumor necrosis factor-α (TNF-α) were determined. Activity of the microsomal triglyceride transfer protein (MTTP) was measured in liver tissue. In comparison with water controls, chronic intake of 30% fructose solution caused a significant increase in hepatic triglycerides, PAI-1 expression and plasma alanine aminotransferase levels in wild-type mice. This effect of fructose feeding was markedly attenuated in PAI-1⁻/⁻ mice. Despite no differences in portal endotoxin levels and hepatic TNF-α protein levels between fructose-fed groups, the protective effect of the loss of PAI-1 against the onset of fructose-induced steatosis was associated with a significant increase in phospho-c-Met, phospho Akt, expression of ApoB and activity of MTTP in livers of PAI-1⁻/⁻ mice in comparison with fructose-fed wild types. Moreover, in PAI-1⁻/⁻ mice, expressions of CD1d and markers of CD1d-reactive NKT cells were markedly higher than in wild-type mice; however, expression of markers of activation of CD1d-reactive NKT cells (eg, interleukin-15 and interferon-γ) were only found to be increased in livers of fructose-fed PAI-1⁻/⁻ mice. Taken together, these data suggest that PAI-1 has a causal role in mediating the early phase of fructose-induced liver damage in mice through signaling cascades downstream of Kupffer cells and TNF-α. PMID:21423135

  17. Transcription factor Bcl11b sustains iNKT1 and iNKT2 cell programs, restricts iNKT17 cell program, and governs iNKT cell survival.

    PubMed

    Uddin, Mohammad Nizam; Sultana, Dil Afroz; Lorentsen, Kyle J; Cho, Jonathan J; Kirst, Mariana E; Brantly, Mark L; Califano, Danielle; Sant'Angelo, Derek B; Avram, Dorina

    2016-07-01

    Invariant natural killer T (iNKT) cells are innate-like T cells that recognize glycolipid antigens and play critical roles in regulation of immune responses. Based on expression of the transcription factors (TFs) Tbet, Plzf, and Rorγt, iNKT cells have been classified in effector subsets that emerge in the thymus, namely, iNKT1, iNKT2, and iNKT17. Deficiency in the TF Bcl11b in double-positive (DP) thymocytes has been shown to cause absence of iNKT cells in the thymus and periphery due to defective self glycolipid processing and presentation by DP thymocytes and undefined intrinsic alterations in iNKT precursors. We used a model of cre-mediated postselection deletion of Bcl11b in iNKT cells to determine its intrinsic role in these cells. We found that Bcl11b is expressed equivalently in all three effector iNKT subsets, and its removal caused a reduction in the numbers of iNKT1 and iNKT2 cells, but not in the numbers of iNKT17 cells. Additionally, we show that Bcl11b sustains subset-specific cytokine production by iNKT1 and iNKT2 cells and restricts expression of iNKT17 genes in iNKT1 and iNKT2 subsets, overall restraining the iNKT17 program in iNKT cells. The total numbers of iNKT cells were reduced in the absence of Bcl11b both in the thymus and periphery, associated with the decrease in iNKT1 and iNKT2 cell numbers and decrease in survival, related to changes in survival/apoptosis genes. Thus, these results extend our understanding of the role of Bcl11b in iNKT cells beyond their selection and demonstrate that Bcl11b is a key regulator of iNKT effector subsets, their function, identity, and survival. PMID:27330109

  18. Neutrophilic granulocytes modulate invariant NKT cell function in mice and humans.

    PubMed

    Wingender, Gerhard; Hiss, Marcus; Engel, Isaac; Peukert, Konrad; Ley, Klaus; Haller, Hermann; Kronenberg, Mitchell; von Vietinghoff, Sibylle

    2012-04-01

    Invariant NKT (iNKT) cells are a conserved αβTCR(+) T cell population that can swiftly produce large amounts of cytokines, thereby activating other leukocytes, including neutrophilic granulocytes (neutrophils). In this study, we investigated the reverse relationship, showing that high neutrophil concentrations suppress the iNKT cell response in mice and humans. Peripheral Vα14 iNKT cells from spontaneously neutrophilic mice produced reduced cytokines in response to the model iNKT cell Ag α-galactosyl ceramide and expressed lower amounts of the T-box transcription factor 21 and GATA3 transcription factor than did wild-type controls. This influence was extrinsic, as iNKT cell transcription factor expression in mixed chimeric mice depended on neutrophil count, not iNKT cell genotype. Transcription factor expression was also decreased in primary iNKT cells from the neutrophil-rich bone marrow compared with spleen in wild-type mice. In vitro, the function of both mouse and human iNKT cells was inhibited by coincubation with neutrophils. This required cell-cell contact with live neutrophils. Neutrophilic inflammation in experimental peritonitis in mice decreased iNKT cell T-box transcription factor 21 and GATA3 expression and α-galactosyl ceramide-induced cytokine production in vivo. This was reverted by blockade of neutrophil mobilization. Similarly, iNKT cells from the human peritoneal cavity expressed lower transcription factor levels during neutrophilic peritonitis. Our data reveal a novel regulatory axis whereby neutrophils reduce iNKT cell responses, which may be important in shaping the extent of inflammation. PMID:22387552

  19. Commensal Microbiota and CD8+ T Cells Shape the Formation of Invariant NKT Cells

    PubMed Central

    Wei, Bo; Wingender, Gerhard; Fujiwara, Daisuke; Chen, Diana YuHui; McPherson, Michael; Brewer, Sarah; Borneman, James; Kronenberg, Mitchell; Braun, Jonathan

    2012-01-01

    Commensal bacteria play an important role in formation of the immune system, but the mechanisms involved are incompletely understood. In this study, we analyze CD1d-restricted invariant NKT (iNKT) cells in germfree mice and in two colonies of C57BL/6 mice termed conventional flora and restricted flora (RF), stably bearing commensal microbial communities of diverse but distinct composition. In germfree mice, iNKT cells were moderately reduced, suggesting that commensal microbiota were partially required for the antigenic drive in maintaining systemic iNKT cells. Surprisingly, even greater depletion of iNKT cell population occurred in RF mice. This was in part attributable to reduced RF levels of intestinal microbial taxa (Sphingomonas spp.) known to express antigenic glycosphingolipid products. However, memory and activated CD8+ T cells were also expanded in RF mice, prompting us to test whether CD8+ T cell activity might be further depleting iNKT cells. Indeed, iNKT cell numbers were restored in RF mice bearing the CD8α−/− genotype or in adult wild-type RF mice acutely depleted with anti-CD8 Ab. Moreover, iNKT cells were restored in RF mice bearing the Prf1−/− phenotype, a key component of cytolytic function. These findings indicate that commensal microbiota, through positive (antigenic drive) and negative (cytolytic depletion by CD8+ T cells) mechanisms, profoundly shape the iNKT cell compartment. Because individuals greatly vary in the composition of their microbial communities, enteric microbiota may play an important epigenetic role in the striking differences in iNKT cell abundance in humans and therefore in their potential contribution to host immune status. PMID:20048124

  20. NKT cells as an ideal anti-tumor immunotherapeutic.

    PubMed

    Fujii, Shin-Ichiro; Shimizu, Kanako; Okamoto, Yoshitaka; Kunii, Naoki; Nakayama, Toshinori; Motohashi, Shinichiro; Taniguchi, Masaru

    2013-01-01

    Human natural killer T (NKT) cells are characterized by their expression of an invariant T cell antigen receptor α chain variable region encoded by a Vα24Jα18 rearrangement. These NKT cells recognize α-galactosylceramide (α-GalCer) in conjunction with the MHC class I-like CD1d molecule and bridge the innate and acquired immune systems to mediate efficient and augmented immune responses. A prime example of one such function is adjuvant activity: NKT cells augment anti-tumor responses because they can rapidly produce large amounts of IFN-γ, which acts on NK cells to eliminate MHC negative tumors and also on CD8 cytotoxic T cells to kill MHC positive tumors. Thus, upon administration of α-GalCer-pulsed DCs, both MHC negative and positive tumor cells can be effectively eliminated, resulting in complete tumor eradication without tumor recurrence. Clinical trials have been completed in a cohort of 17 patients with advanced non-small cell lung cancers and 10 cases of head and neck tumors. Sixty percent of advanced lung cancer patients with high IFN-γ production had significantly prolonged median survival times of 29.3 months with only the primary treatment. In the case of head and neck tumors, 10 patients who completed the trial all had stable disease or partial responses 5 weeks after the combination therapy of α-GalCer-DCs and activated NKT cells. We now focus on two potential powerful treatment options for the future. One is to establish artificial adjuvant vector cells containing tumor mRNA and α-GalCer/CD1d. This stimulates host NKT cells followed by DC maturation and NK cell activation but also induces tumor-specific long-term memory CD8 killer T cell responses, suppressing tumor metastasis even 1 year after the initial single injection. The other approach is to establish induced pluripotent stem (iPS) cells that can generate unlimited numbers of NKT cells with adjuvant activity. Such iPS-derived NKT cells produce IFN-γ in vitro and in vivo upon

  1. Immunoregulation of NKT Cells in Systemic Lupus Erythematosus

    PubMed Central

    Chen, Junwei; Wu, Meng; Wang, Jing; Li, Xiaofeng

    2015-01-01

    Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease with different variety of clinical manifestations. Natural killer T (NKT) cells are innate lymphocytes that play a regulatory role during broad range of immune responses. A number of studies demonstrated that the quantity and quality of invariant NKT (iNKT) cells showed marked defects in SLE patients in comparison to healthy controls. This finding suggests that iNKT cells may play a regulatory role in the occurrence and development of this disease. In this review, we mainly summarized the most recent findings about the behavior of NKT cells in SLE patients and mouse models, as well as how NKT cells affect the proportion of T helper cells and the production of autoreactive antibodies in the progress of SLE. This will help people better understand the role of NKT cells in the development of SLE and improve the therapy strategy. PMID:26819956

  2. Alterations in cellular metabolism modulate CD1d-mediated NKT-cell responses.

    PubMed

    Webb, Tonya J; Carey, Gregory B; East, James E; Sun, Wenji; Bollino, Dominique R; Kimball, Amy S; Brutkiewicz, Randy R

    2016-08-01

    Natural killer T (NKT) cells play a critical role in the host's innate immune response. CD1d-mediated presentation of glycolipid antigens to NKT cells has been established; however, the mechanisms by which NKT cells recognize infected or cancerous cells remain unclear. 5(')-AMP activated protein kinase (AMPK) is a master regulator of lipogenic pathways. We hypothesized that activation of AMPK during infection and malignancy could alter the repertoire of antigens presented by CD1d and serve as a danger signal to NKT cells. In this study, we examined the effect of alterations in metabolism on CD1d-mediated antigen presentation to NKT cells and found that an infection with lymphocytic choriomeningitis virus rapidly increased CD1d-mediated antigen presentation. Hypoxia inducible factors (HIF) enhance T-cell effector functions during infection, therefore antigen presenting cells pretreated with pharmacological agents that inhibit glycolysis, induce HIF and activate AMPK were assessed for their ability to induce NKT-cell responses. Pretreatment with 2-deoxyglucose, cobalt chloride, AICAR and metformin significantly enhanced CD1d-mediated NKT-cell activation. In addition, NKT cells preferentially respond to malignant B cells and B-cell lymphomas express HIF-1α. These data suggest that targeting cellular metabolism may serve as a novel means of inducing innate immune responses. PMID:27297969

  3. Selective Conditions Are Required for the Induction of Invariant NKT Cell Hyporesponsiveness by Antigenic Stimulation.

    PubMed

    Wingender, Gerhard; Birkholz, Alysia M; Sag, Duygu; Farber, Elisa; Chitale, Sampada; Howell, Amy R; Kronenberg, Mitchell

    2015-10-15

    Activation of invariant (i)NKT cells with the model Ag α-galactosylceramide induces rapid production of multiple cytokines, impacting a wide variety of different immune reactions. In contrast, following secondary activation with α-galactosylceramide, the behavior of iNKT cells is altered for months, with the production of most cytokines being strongly reduced. The requirements for the induction of this hyporesponsive state, however, remain poorly defined. In this study, we show that Th1-biasing iNKT cell Ags could induce iNKT cell hyporesponsiveness, as long as a minimum antigenic affinity was reached. In contrast, the Th2-biasing Ag OCH did not induce a hyporesponsive state, nor did cytokine-driven iNKT cell activation by LPS or infections. Furthermore, although dendritic cells and B cells have been reported to be essential for iNKT cell stimulation, neither dendritic cells nor B cells were required to induce iNKT cell hyporesponsiveness. Therefore, our data indicate that whereas some bone marrow-derived cells could induce iNKT cell hyporesponsiveness, selective conditions, dependent on the structure and potency of the Ag, were required to induce hyporesponsiveness. PMID:26355152

  4. iNKT cell cytotoxic responses control T-lymphoma growth in vitro and in vivo

    PubMed Central

    Bassiri, Hamid; Das, Rupali; Guan, Peng; Barrett, David M.; Brennan, Patrick J.; Banerjee, Pinaki P.; Wiener, Susan J.; Orange, Jordan S.; Brenner, Michael B.; Grupp, Stephan A.; Nichols, Kim E.

    2013-01-01

    Invariant natural killer T (iNKT) cells comprise a lineage of CD1d-restricted glycolipid-reactive T lymphocytes with important roles in host immunity to cancer. iNKT cells indirectly participate in antitumor responses by inducing dendritic cell maturation and producing cytokines that promote tumor clearance by CD8+ T and NK cells. Although iNKT cells thereby act as potent cellular adjuvants, it is less clear whether they directly control the growth of tumors. To gain insights into the direct contribution of iNKT cells to tumor immune surveillance, we developed in vitro and in vivo systems to selectively examine the antitumor activity of iNKT cells in the absence of other cytolytic effectors. Using the EL4 T-lymphoma cell line as a model, we find that iNKT cells exert robust and specific lysis of tumor cells in vitro in a manner that is differentially-induced by iNKT cell agonists of varying TCR affinities, such as OCH, α-galactosyl ceramide and PBS44. In vitro blockade of CD1d-mediated lipid antigen presentation, disruption of T cell receptor (TCR) signaling, or loss of perforin expression significantly reduce iNKT cell killing. Consistent with these findings, iNKT cell reconstitution of T, B, and NK cell-deficient mice slows EL4 growth in vivo via TCR-CD1d and perforin-dependent mechanisms. Together, these observations establish that iNKT cells are sufficient to control the growth of T-lymphoma in vitro and in vivo. They also suggest that the induction of iNKT cell cytotoxic responses in situ might serve as a more effective strategy to prevent and/or treat CD1d+ cancers, such as T-lymphoma. PMID:24563871

  5. Dynamics of NKT-Cell Responses to Chlamydial Infection

    PubMed Central

    Shekhar, Sudhanshu; Joyee, Antony George; Yang, Xi

    2015-01-01

    Natural killer T (NKT) cells have gained great attention owing to their critical functional roles in immunity to various pathogens. In this review, we provide an overview of the current knowledge on the role of NKT cells in host defense against and pathogenesis due to Chlamydia, which is an intracellular bacterial pathogen that poses a threat to the public health worldwide. Accumulating evidence has demonstrated that NKT cells, particularly invariant NKT (iNKT) cells, play a crucial role in host defense against chlamydial infections, especially in C. pneumoniae infection. iNKT cells can promote type-1 protective responses to C. pneumoniae by inducing enhanced production of IL-12 by dendritic cells (DCs), in particular CD8α+ DCs, which promote the differentiation of naive T cells into protective IFN-γ-producing Th1/Tc1 type CD4+/CD8+ T cells. This iNKT-cell-mediated modulation of DC function is largely dependent upon CD40–CD40L interaction, IFN-γ production, and cell-to-cell contact. In addition, iNKT cells modulate the function of natural killer cells. NKT cells may be also involved in the pathogenesis of some chlamydial diseases by inducing different patterns of cytokine production. A better understanding of NKT-cell biology will enable us to rationally design prophylactic and therapeutic tools to combat infectious diseases. PMID:26029217

  6. Pak2 Controls Acquisition of NKT Cell Fate by Regulating Expression of the Transcription Factors PLZF and Egr2.

    PubMed

    O'Hagan, Kyle L; Zhao, Jie; Pryshchep, Olga; Wang, Chyung-Ru; Phee, Hyewon

    2015-12-01

    NKT cells constitute a small population of T cells developed in the thymus that produce large amounts of cytokines and chemokines in response to lipid Ags. Signaling through the Vα14-Jα18 TCR instructs commitment to the NKT cell lineage, but the precise signaling mechanisms that instruct their lineage choice are unclear. In this article, we report that the cytoskeletal remodeling protein, p21-activated kinase 2 (Pak2), was essential for NKT cell development. Loss of Pak2 in T cells reduced stage III NKT cells in the thymus and periphery. Among different NKT cell subsets, Pak2 was necessary for the generation and function of NKT1 and NKT2 cells, but not NKT17 cells. Mechanistically, expression of Egr2 and promyelocytic leukemia zinc finger (PLZF), two key transcription factors for acquiring the NKT cell fate, were markedly diminished in the absence of Pak2. Diminished expression of Egr2 and PLZF were not caused by aberrant TCR signaling, as determined using a Nur77-GFP reporter, but were likely due to impaired induction and maintenance of signaling lymphocyte activation molecule 6 expression, a TCR costimulatory receptor required for NKT cell development. These data suggest that Pak2 controls thymic NKT cell development by providing a signal that links Egr2 to induce PLZF, in part by regulating signaling lymphocyte activation molecule 6 expression. PMID:26519537

  7. Innate recognition of cell wall β-glucans drives invariant Natural Killer T (iNKT) cell responses against fungi

    PubMed Central

    Cohen, Nadia R.; Tatituri, Raju V.V.; Rivera, Amariliz; Watts, Gerald F.M.; Kim, Edy Y.; Chiba, Asako; Fuchs, Beth B.; Mylonakis, Eleftherios; Besra, Gurdyal S.; Levitz, Stuart M.; Brigl, Manfred; Brenner, Michael B.

    2016-01-01

    SUMMARY iNKT cells are innate T lymphocytes recognizing endogenous and foreign lipid antigens presented in the MHC-like molecule CD1d. The semi-invariant iNKT cell TCR can detect certain bacterial and parasitic lipids, and drive iNKT cell responses. How iNKT cells respond to fungi, however, is unknown. We found that CD1d-deficient mice, which lack iNKT cells, poorly control infection with the fungal pathogen Aspergillus fumigatus. Furthermore, A. fumigatus rapidly activates iNKT cells in vivo and in vitro in the presence of APCs. Surprisingly, despite a requirement for CD1d recognition, the anti-fungal iNKT cell response does not require fungal lipids. Instead, Dectin-1 and MyD88-mediated responses to β-1,3 glucans, major fungal cell-wall polysaccharides, trigger IL-12 production by APCs that drives self-reactive iNKT cells to secrete IFN-γ. Innate recognition of β-1,3 glucans also drives iNKT cell responses against Candida, Histoplasma and Alternaria, suggesting that this mechanism may broadly define the basis for anti-fungal iNKT cell responses. PMID:22100160

  8. Effects of Invariant NKT Cells on Parasite Infections and Hygiene Hypothesis.

    PubMed

    Yang, Jun-Qi; Zhou, Yonghua; Singh, Ram Raj

    2016-01-01

    Invariant natural killer T (iNKT) cells are unique subset of innate-like T cells recognizing glycolipids. iNKT cells can rapidly produce copious amounts of cytokines upon antigen stimulation and exert potent immunomodulatory activities for a wide variety of immune responses and diseases. We have revealed the regulatory effect of iNKT cells on autoimmunity with a serial of publications. On the other hand, the role of iNKT cells in parasitic infections, especially in recently attractive topic "hygiene hypothesis," has not been clearly defined yet. Bacterial and parasitic cell wall is a cellular structure highly enriched in a variety of glycolipids and lipoproteins, some of which may serve as natural ligands of iNKT cells. In this review, we mainly summarized the recent findings on the roles and underlying mechanisms of iNKT cells in parasite infections and their cross-talk with Th1, Th2, Th17, Treg, and innate lymphoid cells. In most cases, iNKT cells exert regulatory or direct cytotoxic roles to protect hosts against parasite infections. We put particular emphasis as well on the identification of the natural ligands from parasites and the involvement of iNKT cells in the hygiene hypothesis. PMID:27563682

  9. Effects of Invariant NKT Cells on Parasite Infections and Hygiene Hypothesis

    PubMed Central

    Zhou, Yonghua

    2016-01-01

    Invariant natural killer T (iNKT) cells are unique subset of innate-like T cells recognizing glycolipids. iNKT cells can rapidly produce copious amounts of cytokines upon antigen stimulation and exert potent immunomodulatory activities for a wide variety of immune responses and diseases. We have revealed the regulatory effect of iNKT cells on autoimmunity with a serial of publications. On the other hand, the role of iNKT cells in parasitic infections, especially in recently attractive topic “hygiene hypothesis,” has not been clearly defined yet. Bacterial and parasitic cell wall is a cellular structure highly enriched in a variety of glycolipids and lipoproteins, some of which may serve as natural ligands of iNKT cells. In this review, we mainly summarized the recent findings on the roles and underlying mechanisms of iNKT cells in parasite infections and their cross-talk with Th1, Th2, Th17, Treg, and innate lymphoid cells. In most cases, iNKT cells exert regulatory or direct cytotoxic roles to protect hosts against parasite infections. We put particular emphasis as well on the identification of the natural ligands from parasites and the involvement of iNKT cells in the hygiene hypothesis. PMID:27563682

  10. Diverse cytokine production by NKT cell subsets and identification of an IL-17–producing CD4−NK1.1− NKT cell population

    PubMed Central

    Coquet, Jonathan M.; Chakravarti, Sumone; Kyparissoudis, Konstantinos; McNab, Finlay W.; Pitt, Lauren A.; McKenzie, Brent S.; Berzins, Stuart P.; Smyth, Mark J.; Godfrey, Dale I.

    2008-01-01

    NKT cell subsets can be divided based on CD4 and NK1.1 expression and tissue of origin, but the developmental and functional relationships between the different subsets still are poorly understood. A comprehensive study of 19 cytokines across different NKT cell subsets revealed that no two NKT subpopulations exhibited the same cytokine profile, and, remarkably, the amounts of each cytokine produced varied by up to 100-fold or more among subsets. This study also revealed the existence of a population of CD4−NK1.1− NKT cells that produce high levels of the proinflammatory cytokine IL-17 within 2–3 h of activation. On intrathymic transfer these cells develop into mature CD4−NK1.1+ but not into CD4+NK1.1+ NKT cells, indicating that CD4−NK1.1− NKT cells include an IL-17–producing subpopulation, and also mark the elusive branch point for CD4+ and CD4− NKT cell sublineages. PMID:18685112

  11. Cognate interaction with iNKT cells expands IL-10-producing B regulatory cells.

    PubMed

    Vomhof-DeKrey, Emilie E; Yates, Jennifer; Hägglöf, Thomas; Lanthier, Paula; Amiel, Eyal; Veerapen, Natacha; Besra, Gurdyal S; Karlsson, Mikael C I; Leadbetter, Elizabeth A

    2015-10-01

    Successful induction of B-cell activation and memory depends on help from CD4+ T cells. Invariant natural killer T (iNKT) cells (glycolipid-specific, CD1d-restricted innate lymphocytes) provide both cognate (direct) and noncognate (indirect) helper signals to enhance B-cell responses. Both forms of iNKT-cell help induce primary humoral immune responses, but only noncognate iNKT-cell help drives humoral memory and plasma cells. Here, we show that iNKT cognate help for B cells is fundamentally different from the help provided by conventional CD4+ T cells. Cognate iNKT-cell help drives an early, unsustained germinal center B-cell expansion, less reduction of T follicular regulatory cells, an expansion of marginal zone B cells, and early increases in regulatory IL-10-producing B-cell numbers compared with noncognate activation. These results are consistent with a mechanism whereby iNKT cells preferentially provide an innate form of help that does not generate humoral memory and has important implications for the application of glycolipid molecules as vaccine adjuvants. PMID:26392556

  12. Cognate interaction with iNKT cells expands IL-10–producing B regulatory cells

    PubMed Central

    Vomhof-DeKrey, Emilie E.; Yates, Jennifer; Hägglöf, Thomas; Lanthier, Paula; Amiel, Eyal; Veerapen, Natacha; Besra, Gurdyal S.; Karlsson, Mikael C. I.; Leadbetter, Elizabeth A.

    2015-01-01

    Successful induction of B-cell activation and memory depends on help from CD4+ T cells. Invariant natural killer T (iNKT) cells (glycolipid-specific, CD1d-restricted innate lymphocytes) provide both cognate (direct) and noncognate (indirect) helper signals to enhance B-cell responses. Both forms of iNKT-cell help induce primary humoral immune responses, but only noncognate iNKT-cell help drives humoral memory and plasma cells. Here, we show that iNKT cognate help for B cells is fundamentally different from the help provided by conventional CD4+ T cells. Cognate iNKT-cell help drives an early, unsustained germinal center B-cell expansion, less reduction of T follicular regulatory cells, an expansion of marginal zone B cells, and early increases in regulatory IL-10–producing B-cell numbers compared with noncognate activation. These results are consistent with a mechanism whereby iNKT cells preferentially provide an innate form of help that does not generate humoral memory and has important implications for the application of glycolipid molecules as vaccine adjuvants. PMID:26392556

  13. Thymic and peripheral microenvironments differentially mediate development and maturation of iNKT cells by IL-15 transpresentation.

    PubMed

    Castillo, Eliseo F; Acero, Luis F; Stonier, Spencer W; Zhou, Dapeng; Schluns, Kimberly S

    2010-10-01

    Invariant NKT (iNKT) cells are an innate type of T cells, which respond rapidly on activation. iNKT cells acquire these innate-like abilities during development; however, the signals driving development and functional maturation remain only partially understood. Because interleukin-15 (IL-15) is crucial for iNKT development and is delivered by transpresentation, we set out to identify the cell types providing IL-15 to developing iNKT cells and determine their role at the various states of development and maturation. We report here that transpresentation of IL-15 by parenchymal cells was crucial for generating normal number of iNKTs in the thymus, whereas both hematopoietic and parenchymal cells regulated iNKT cell numbers in the periphery, particularly in the liver. Specifically, dendritic cells contributed to peripheral iNKT cell numbers by up-regulating Bcl-2 expression and promoting extrathymic iNKT cell ex-pansion and their homeostatic proliferation. Whether IL-15 affects functional maturation of iNKT cells was also examined. In IL-15Rα(-/-) mice, CD44(High)NK1.1(+) iNKT cells displayed decreased T-bet expression and in response to α-galactosylceramide, had deficient interferon-γ expression. Such defects could be reversed by exogenous IL-15 signals. Overall, these studies identify stage-specific functions of IL-15, which are determined by the tissue microenvironment and elucidate the importance of IL-15 in functional maturation. PMID:20581314

  14. Thymic and peripheral microenvironments differentially mediate development and maturation of iNKT cells by IL-15 transpresentation

    PubMed Central

    Castillo, Eliseo F.; Acero, Luis F.; Stonier, Spencer W.; Zhou, Dapeng

    2010-01-01

    Invariant NKT (iNKT) cells are an innate type of T cells, which respond rapidly on activation. iNKT cells acquire these innate-like abilities during development; however, the signals driving development and functional maturation remain only partially understood. Because interleukin-15 (IL-15) is crucial for iNKT development and is delivered by transpresentation, we set out to identify the cell types providing IL-15 to developing iNKT cells and determine their role at the various states of development and maturation. We report here that transpresentation of IL-15 by parenchymal cells was crucial for generating normal number of iNKTs in the thymus, whereas both hematopoietic and parenchymal cells regulated iNKT cell numbers in the periphery, particularly in the liver. Specifically, dendritic cells contributed to peripheral iNKT cell numbers by up-regulating Bcl-2 expression and promoting extrathymic iNKT cell ex-pansion and their homeostatic proliferation. Whether IL-15 affects functional maturation of iNKT cells was also examined. In IL-15Rα−/− mice, CD44HighNK1.1+ iNKT cells displayed decreased T-bet expression and in response to α-galactosylceramide, had deficient interferon-γ expression. Such defects could be reversed by exogenous IL-15 signals. Overall, these studies identify stage-specific functions of IL-15, which are determined by the tissue microenvironment and elucidate the importance of IL-15 in functional maturation. PMID:20581314

  15. The Response of CD1d-Restricted Invariant NKT Cells to Microbial Pathogens and Their Products

    PubMed Central

    Van Kaer, Luc; Parekh, Vrajesh V.; Wu, Lan

    2015-01-01

    Invariant natural killer T (iNKT) cells become activated during a wide variety of infections. This includes organisms lacking cognate CD1d-binding glycolipid antigens recognized by the semi-invariant T cell receptor of iNKT cells. Additional studies have shown that iNKT cells also become activated in vivo in response to microbial products such as bacterial lipopolysaccharide, a potent inducer of cytokine production in antigen-presenting cells (APCs). Other studies have shown that iNKT cells are highly responsive to stimulation by cytokines such as interleukin-12. These findings have led to the concept that microbial pathogens can activate iNKT cells either directly via glycolipids or indirectly by inducing cytokine production in APCs. iNKT cells activated in this manner produce multiple cytokines that can influence the outcome of infection, usually in favor of the host, although potent iNKT cell activation may contribute to an uncontrolled cytokine storm and sepsis. One aspect of the response of iNKT cells to microbial pathogens is that it is short-lived and followed by an extended time period of unresponsiveness to reactivation. This refractory period may represent a means to avoid chronic activation and cytokine production by iNKT cells, thus protecting the host against some of the negative effects of iNKT cell activation, but potentially putting the host at risk for secondary infections. These effects of microbial pathogens and their products on iNKT cells are not only important for understanding the role of these cells in immune responses against infections but also for the development of iNKT cell-based therapies. PMID:26029211

  16. NKT cell subsets as key participants in liver physiology and pathology

    PubMed Central

    Bandyopadhyay, Keya; Marrero, Idania; Kumar, Vipin

    2016-01-01

    Natural killer T (NKT) cells are innate-like lymphocytes that generally recognize lipid antigens and are enriched in microvascular compartments of the liver. NKT cells can be activated by self- or microbial-lipid antigens and by signaling through toll-like receptors. Following activation, NKT cells rapidly secrete pro-inflammatory or anti-inflammatory cytokines and chemokines, and thereby determine the milieu for subsequent immunity or tolerance. It is becoming clear that two different subsets of NKT cells—type I and type II—have different modes of antigen recognition and have opposing roles in inflammatory liver diseases. Here we focus mainly on the roles of both NKT cell subsets in the maintenance of immune tolerance and inflammatory diseases in liver. Furthermore, how the differential activation of type I and type II NKT cells influences other innate cells and adaptive immune cells to result in important consequences for tissue integrity is discussed. It is crucial that better reagents, including CD1d tetramers, be used in clinical studies to define the roles of NKT cells in liver diseases in patients. PMID:26972772

  17. Generation of Mouse iNKT Cell Lines

    PubMed Central

    Li, Xiangming; Tsuji, Moriya; Schneck, Jonathan; Webb, Tonya J.

    2016-01-01

    Natural killer T (NKT) cells bridge the innate and adaptive arms of the immune system, and manipulating their effector functions can have therapeutic significances in the treatment of autoimmunity, transplant biology, infectious disease and cancer. This important lymphocyte subset regulates the immune system through their potent cytokine production following the recognition of lipid antigen present in the context of the MHC class I-like CD1d molecule, in addition their ability to directly mediate cytotoxicity. Here, we describe a method of expanding mouse invariant NKT (iNKT) cell lines from mononuclear cells isolated from the thymus, spleen, or liver using bone marrow derived dendritic cells. These iNKT cell lines can be used study their co-signaling requirements, cytokine profiles and cytotoxic functions which will greatly enhance our knowledge of iNKT cell biology.

  18. Inhibitory function of NKT cells during early induction phase of nickel allergy.

    PubMed

    Okuno, Hironori; Satoh, Masashi; Takeuchi, Emiko; Eshima, Koji; Terashima, Masazumi; Komotori, Jun; Habu, Sonoko; Tamauchi, Hidekazu; Iwabuchi, Kazuya

    2016-07-01

    Until now, metal allergies have been regarded as a Th1-type immune response. However, because the contribution of a Th2-type immune response has been suggested by clinical findings, we previously examined the Th2-type immune response during the development of metal allergies using a GATA-3 transgenic (GATA-3 Tg) mouse model. As a result, a Th2-type immunization reaction was suggested to be involved in the early phase of metal allergies. Recently, the involvement of NKT cells in metal allergies has been suggested. We examined this possibility using the activation of NKT cells and an NKT cell-deficient mouse model to determine the contribution of NKT cells to nickel allergy in the present study. In NKT cell-deficient mice, ear swelling was remarkably increased, compared with that in control mice. Also, in mice that had been treated with α-galactosylceramide (α-GalCer) to activate NKT cells, the ear swelling response was remarkably inhibited, compared with that in untreated mice. These facts show that NKT cells are involved in the inhibition of nickel allergy-induced ear swelling responses. PMID:26868431

  19. Natural killer T (NKT) cells accelerate Shiga toxin type 2 (Stx2) pathology in mice.

    PubMed

    Obata, Fumiko; Subrahmanyam, Priyanka B; Vozenilek, Aimee E; Hippler, Lauren M; Jeffers, Tynae; Tongsuk, Methinee; Tiper, Irina; Saha, Progyaparamita; Jandhyala, Dakshina M; Kolling, Glynis L; Latinovic, Olga; Webb, Tonya J

    2015-01-01

    Shiga toxin-producing Escherichia coli (STEC) is a leading cause of childhood renal disease Hemolytic Uremic Syndrome (HUS). The involvement of renal cytokines and chemokines is suspected to play a critical role in disease progression. In current article, we tested the hypothesis that NKT cells are involved in Stx2-induced pathology in vivo. To address this hypothesis we compared Stx2 toxicity in WT and CD1 knockout (KO) mice. In CD1KO mice, which lack natural killer T (NKT) cells, Stx2-induced pathologies such as weight loss, renal failure, and death were delayed. In WT mice, Stx2-specific selective increase in urinary albumin occurs in later time points, and this was also delayed in NKT cell deficient mice. NKT cell-associated cytokines such as IL-2, IL-4, IFN-γ, and IL-17 were detected in kidney lysates of Stx2-injected WT mice with the peak around 36 h after Stx2 injection. In CD1KO, there was a delay in the kinetics, and increases in these cytokines were observed 60 h post Stx2 injection. These data suggest that NKT cells accelerate Stx2-induced pathology in mouse kidneys. To determine the mechanism by which NKT cells promote Stx2-associated disease, in vitro studies were performed using murine renal cells. We found that murine glomerular endothelial cells and podocytes express functional CD1d molecules and can present exogenous antigen to NKT cells. Moreover, we observed the direct interaction between Stx2 and the receptor Gb3 on the surface of mouse renal cells by 3D STORM-TIRF which provides single molecule imaging. Collectively, these data suggest that Stx2 binds to Gb3 on renal cells and leads to aberrant CD1d-mediated NKT cell activation. Therefore, strategies targeting NKT cells could have a significant impact on Stx2-associated renal pathology in STEC disease. PMID:25904903

  20. Natural killer T (NKT) cells accelerate Shiga toxin type 2 (Stx2) pathology in mice

    PubMed Central

    Obata, Fumiko; Subrahmanyam, Priyanka B.; Vozenilek, Aimee E.; Hippler, Lauren M.; Jeffers, Tynae; Tongsuk, Methinee; Tiper, Irina; Saha, Progyaparamita; Jandhyala, Dakshina M.; Kolling, Glynis L.; Latinovic, Olga; Webb, Tonya J.

    2015-01-01

    Shiga toxin-producing Escherichia coli (STEC) is a leading cause of childhood renal disease Hemolytic Uremic Syndrome (HUS). The involvement of renal cytokines and chemokines is suspected to play a critical role in disease progression. In current article, we tested the hypothesis that NKT cells are involved in Stx2-induced pathology in vivo. To address this hypothesis we compared Stx2 toxicity in WT and CD1 knockout (KO) mice. In CD1KO mice, which lack natural killer T (NKT) cells, Stx2-induced pathologies such as weight loss, renal failure, and death were delayed. In WT mice, Stx2-specific selective increase in urinary albumin occurs in later time points, and this was also delayed in NKT cell deficient mice. NKT cell-associated cytokines such as IL-2, IL-4, IFN-γ, and IL-17 were detected in kidney lysates of Stx2-injected WT mice with the peak around 36 h after Stx2 injection. In CD1KO, there was a delay in the kinetics, and increases in these cytokines were observed 60 h post Stx2 injection. These data suggest that NKT cells accelerate Stx2-induced pathology in mouse kidneys. To determine the mechanism by which NKT cells promote Stx2-associated disease, in vitro studies were performed using murine renal cells. We found that murine glomerular endothelial cells and podocytes express functional CD1d molecules and can present exogenous antigen to NKT cells. Moreover, we observed the direct interaction between Stx2 and the receptor Gb3 on the surface of mouse renal cells by 3D STORM-TIRF which provides single molecule imaging. Collectively, these data suggest that Stx2 binds to Gb3 on renal cells and leads to aberrant CD1d-mediated NKT cell activation. Therefore, strategies targeting NKT cells could have a significant impact on Stx2-associated renal pathology in STEC disease. PMID:25904903

  1. Type II NKT-TFH cells against Gaucher lipids regulate B-cell immunity and inflammation

    PubMed Central

    Nair, Shiny; Boddupalli, Chandra Sekhar; Verma, Rakesh; Liu, Jun; Yang, Ruhua; Pastores, Gregory M.; Mistry, Pramod K.

    2015-01-01

    Chronic inflammation including B-cell activation is commonly observed in both inherited (Gaucher disease [GD]) and acquired disorders of lipid metabolism. However, the cellular mechanisms underlying B-cell activation in these settings remain to be elucidated. Here, we report that β-glucosylceramide 22:0 (βGL1-22) and glucosylsphingosine (LGL1), 2 major sphingolipids accumulated in GD, can be recognized by a distinct subset of CD1d-restricted human and murine type II natural killer T (NKT) cells. Human βGL1-22– and LGL1-reactive CD1d tetramer–positive T cells have a distinct T-cell receptor usage and genomic and cytokine profiles compared with the classical type I NKT cells. In contrast to type I NKT cells, βGL1-22– and LGL1-specific NKT cells constitutively express T-follicular helper (TFH) phenotype. Injection of these lipids leads to an increase in respective lipid-specific type II NKT cells in vivo and downstream induction of germinal center B cells, hypergammaglobulinemia, and production of antilipid antibodies. Human βGL1-22– and LGL1-specific NKT cells can provide efficient cognate help to B cells in vitro. Frequency of LGL1-specific T cells in GD mouse models and patients correlates with disease activity and therapeutic response. Our studies identify a novel type II NKT-mediated pathway for glucosphingolipid-mediated dysregulation of humoral immunity and increased risk of B-cell malignancy observed in metabolic lipid disorders. PMID:25499455

  2. NKT cells prevent chronic joint inflammation after infection with Borrelia burgdorferi.

    PubMed

    Tupin, Emmanuel; Benhnia, Mohammed Rafii-El-Idrissi; Kinjo, Yuki; Patsey, Rebeca; Lena, Christopher J; Haller, Matthew C; Caimano, Melissa J; Imamura, Masakazu; Wong, Chi-Huey; Crotty, Shane; Radolf, Justin D; Sellati, Timothy J; Kronenberg, Mitchell

    2008-12-16

    Borrelia burgdorferi is the etiologic agent of Lyme disease, a multisystem inflammatory disorder that principally targets the skin, joints, heart, and nervous system. The role of T lymphocytes in the development of chronic inflammation resulting from B. burgdorferi infection has been controversial. We previously showed that natural killer T (NKT) cells with an invariant (i) TCR alpha chain (iNKT cells) recognize glycolipids from B. burgdorferi, but did not establish an in vivo role for iNKT cells in Lyme disease pathogenesis. Here, we evaluate the importance of iNKT cells for host defense against these pathogenic spirochetes by using Valpha14i NKT cell-deficient (Jalpha18(-/-)) BALB/c mice. On tick inoculation with B. burgdorferi, Jalpha18(-/-) mice exhibited more severe and prolonged arthritis as well as a reduced ability to clear spirochetes from infected tissues. Valpha14i NKT cell deficiency also resulted in increased production of antibodies directed against both B. burgdorferi protein antigens and borrelial diacylglycerols; the latter finding demonstrates that anti-glycolipid antibody production does not require cognate help from Valpha14i NKT cells. Valpha14i NKT cells in infected wild-type mice expressed surface activation markers and produced IFNgamma in vivo after infection, suggesting a participatory role for this unique population in cellular immunity. Our data are consistent with the hypothesis that the antigen-specific activation of Valpha14i NKT cells is important for the prevention of persistent joint inflammation and spirochete clearance, and they counter the long-standing notion that humoral rather than cellular immunity is sufficient to facilitate Lyme disease resolution. PMID:19060201

  3. NKT cells prevent chronic joint inflammation after infection with Borrelia burgdorferi

    PubMed Central

    Tupin, Emmanuel; Benhnia, Mohammed Rafii-El-Idrissi; Kinjo, Yuki; Patsey, Rebeca; Lena, Christopher J.; Haller, Matthew C.; Caimano, Melissa J.; Imamura, Masakazu; Wong, Chi-Huey; Crotty, Shane; Radolf, Justin D.; Sellati, Timothy J.; Kronenberg, Mitchell

    2008-01-01

    Borrelia burgdorferi is the etiologic agent of Lyme disease, a multisystem inflammatory disorder that principally targets the skin, joints, heart, and nervous system. The role of T lymphocytes in the development of chronic inflammation resulting from B. burgdorferi infection has been controversial. We previously showed that natural killer T (NKT) cells with an invariant (i) TCR α chain (iNKT cells) recognize glycolipids from B. burgdorferi, but did not establish an in vivo role for iNKT cells in Lyme disease pathogenesis. Here, we evaluate the importance of iNKT cells for host defense against these pathogenic spirochetes by using Vα14i NKT cell-deficient (Jα18−/−) BALB/c mice. On tick inoculation with B. burgdorferi, Jα18−/− mice exhibited more severe and prolonged arthritis as well as a reduced ability to clear spirochetes from infected tissues. Vα14i NKT cell deficiency also resulted in increased production of antibodies directed against both B. burgdorferi protein antigens and borrelial diacylglycerols; the latter finding demonstrates that anti-glycolipid antibody production does not require cognate help from Vα14i NKT cells. Vα14i NKT cells in infected wild-type mice expressed surface activation markers and produced IFNγ in vivo after infection, suggesting a participatory role for this unique population in cellular immunity. Our data are consistent with the hypothesis that the antigen-specific activation of Vα14i NKT cells is important for the prevention of persistent joint inflammation and spirochete clearance, and they counter the long-standing notion that humoral rather than cellular immunity is sufficient to facilitate Lyme disease resolution. PMID:19060201

  4. Foxp3 regulates ratio of Treg and NKT cells in a mouse model of asthma.

    PubMed

    Lu, Yanming; Guo, Yinshi; Xu, Linyun; Li, Yaqin; Cao, Lanfang

    2015-05-01

    Chronic inflammatory disorder of the airways causes asthma. Regulatory T cells (Treg cells) and Natural killer T cells (NKT cells) both play critical roles in the pathogenesis of asthma. Activation of Treg cells requires Foxp3, whereas whether Foxp3 may regulate the ratio of Treg and NKT cells to affect asthma is uncertain. In an ovalbumin (OVA)-induced mouse model of asthma, we either increased Treg cells by lentivirus-mediated forced expression of exogenous Foxp3, or increased NKT cells by stimulation with its activator α-GalCer. We found that the CD4+CD25+ Treg cells increased by forced Foxp3 expression, and decreased by α-GalCer, while the CD3+CD161+ NKT cells decreased by forced Foxp3 expression, and increased by α-GalCer. Moreover, forced Foxp3 expression, but not α-GalCer, significantly alleviated the hallmarks of asthma. Furthermore, forced Foxp3 increased levels of IL_10 and TGFβ1, and α-GalCer increased levels of IL_4 and INFγ in the OVA-treated lung. Taken together, our study suggests that Foxp3 may activate Treg cells and suppress NKT cells in asthma. Treg and NKT cells may antagonize the effects of each other in asthma. PMID:25636804

  5. CD1d Expression and Invariant NKT Cell Responses in Herpesvirus Infections

    PubMed Central

    Chung, Brian K.; Priatel, John J.; Tan, Rusung

    2015-01-01

    Invariant natural killer T (iNKT) cells are a highly conserved subset of unconventional T lymphocytes that express a canonical, semi-invariant T cell receptor and surface markers shared with the natural killer cell lineage. iNKT cells recognize exogenous and endogenous glycolipid antigens restricted by non-polymorphic CD1d molecules, and are highly responsive to the prototypical agonist, α-galactosylceramide. Upon activation, iNKT cells rapidly coordinate signaling between innate and adaptive immune cells through the secretion of proinflammatory cytokines, leading to the maturation of antigen-presenting cells, and expansion of antigen-specific CD4+ and CD8+ T cells. Because of their potent immunoregulatory properties, iNKT cells have been extensively studied and are known to play a pivotal role in mediating immune responses against microbial pathogens including viruses. Here, we review evidence that herpesviruses manipulate CD1d expression to escape iNKT cell surveillance and establish lifelong latency in humans. Collectively, published findings suggest that iNKT cells play critical roles in anti-herpesvirus immune responses and could be harnessed therapeutically to limit viral infection and viral-associated disease. PMID:26161082

  6. miR-150 regulates the development of NK and iNKT cells

    PubMed Central

    Bezman, Natalie A.; Chakraborty, Tirtha; Bender, Timothy

    2011-01-01

    Natural killer (NK) and invariant NK T (iNKT) cells are critical in host defense against pathogens and for the initiation of adaptive immune responses. miRNAs play important roles in NK and iNKT cell development, maturation, and function, but the roles of specific miRNAs are unclear. We show that modulation of miR-150 expression levels has a differential effect on NK and iNKT cell development. Mice with a targeted deletion of miR-150 have an impaired, cell lineage–intrinsic defect in their ability to generate mature NK cells. Conversely, a gain-of-function miR-150 transgene promotes the development of NK cells, which display a more mature phenotype and are more responsive to activation. In contrast, overexpression of miR-150 results in a substantial reduction of iNKT cells in the thymus and in the peripheral lymphoid organs. The transcription factor c-Myb has been shown to be a direct target of miR-150. Our finding of increased NK cell and decreased iNKT cell frequencies in Myb heterozygous bone marrow chimeras suggests that miR-150 differentially controls the development of NK and iNKT cell lineages by targeting c-Myb. PMID:22124110

  7. iNKT cells require TSC1 for terminal maturation and effector lineage fate decisions

    PubMed Central

    Wu, Jinhong; Yang, Jialong; Yang, Kai; Wang, Hongxia; Gorentla, Balachandra; Shin, Jinwook; Qiu, Yurong; Que, Loretta G.; Foster, W. Michael; Xia, Zhenwei; Chi, Hongbo; Zhong, Xiao-Ping

    2014-01-01

    Terminal maturation of invariant NKT (iNKT) cells from stage 2 (CD44+NK1.1–) to stage 3 (CD44+NK1.1+) is accompanied by a functional acquisition of a predominant IFN-γ–producing (iNKT-1) phenotype; however, some cells develop into IL-17–producing iNKT (iNKT-17) cells. iNKT-17 cells are rare and restricted to a CD44+NK1.1– lineage. It is unclear how iNKT terminal maturation is regulated and what factors mediate the predominance of iNKT-1 compared with iNKT-17. The tumor suppressor tuberous sclerosis 1 (TSC1) is an important negative regulator of mTOR signaling, which regulates T cell differentiation, function, and trafficking. Here, we determined that mice lacking TSC1 exhibit a developmental block of iNKT differentiation at stage 2 and skew from a predominantly iNKT-1 population toward a predominantly iNKT-17 population, leading to enhanced airway hypersensitivity. Evaluation of purified iNKT cells revealed that TSC1 promotes T-bet, which regulates iNKT maturation, but downregulates ICOS expression in iNKT cells by inhibiting mTOR complex 1 (mTORC1). Furthermore, mice lacking T-bet exhibited both a terminal maturation defect of iNKT cells and a predominance of iNKT-17 cells, and increased ICOS expression was required for the predominance of iNKT-17 cells in the population of TSC1-deficient iNKT cells. Our data indicate that TSC1-dependent control of mTORC1 is crucial for terminal iNKT maturation and effector lineage decisions, resulting in the predominance of iNKT-1 cells. PMID:24614103

  8. NKT cell–dependent leukemia eradication following stem cell mobilization with potent G-CSF analogs

    PubMed Central

    Morris, Edward S.; MacDonald, Kelli P.A.; Rowe, Vanessa; Banovic, Tatjana; Kuns, Rachel D.; Don, Alistair L.J.; Bofinger, Helen M.; Burman, Angela C.; Olver, Stuart D.; Kienzle, Norbert; Porcelli, Steven A.; Pellicci, Daniel G.; Godfrey, Dale I.; Smyth, Mark J.; Hill, Geoffrey R.

    2005-01-01

    NKT cells have pivotal roles in immune regulation and tumor immunosurveillance. We report that the G-CSF and FMS-like tyrosine kinase 3 ligand (Flt-3L) chimeric cytokine, progenipoietin-1, markedly expands the splenic and hepatic NKT cell population and enhances functional responses to α-galactosylceramide. In a murine model of allogeneic stem cell transplantation, donor NKT cells promoted host DC activation and enhanced perforin-restricted CD8+ T cell cytotoxicity against host-type antigens. Following leukemic challenge, donor treatment with progenipoietin-1 significantly improved overall survival when compared with G-CSF or control, attributable to reduced graft-versus-host disease mortality and paradoxical augmentation of graft-versus-leukemia (GVL) effects. Enhanced cellular cytotoxicity was dependent on donor NKT cells, and leukemia clearance was profoundly impaired in recipients of NKT cell–deficient grafts. Enhanced cytotoxicity and GVL effects were not associated with Flt-3L signaling or effects on DCs but were reproduced by prolonged G-CSF receptor engagement with pegylated G-CSF. Thus, modified G-CSF signaling during stem cell mobilization augments NKT cell–dependent CD8+ cytotoxicity, effectively separating graft-versus-host disease and GVL and greatly expanding the potential applicability of allogeneic stem cell transplantation for the therapy of malignant disease. PMID:16224535

  9. Functional Invariant NKT Cells in Pig Lungs Regulate the Airway Hyperreactivity: A Potential Animal Model

    PubMed Central

    Manickam, Cordelia; Khatri, Mahesh; Rauf, Abdul; Li, Xiangming; Tsuji, Moriya; Rajashekara, Gireesh; Dwivedi, Varun

    2015-01-01

    Important roles played by invariant natural killer T (iNKT) cells in asthma pathogenesis have been demonstrated. We identified functional iNKT cells and CD1d molecules in pig lungs. Pig iNKT cells cultured in the presence of α-GalCer proliferated and secreted Th1 and Th2 cytokines. Like in other animal models, direct activation of pig lung iNKT cells using α-GalCer resulted in acute airway hyperreactivity (AHR). Clinically, acute AHR-induced pigs had increased respiratory rate, enhanced mucus secretion in the airways, fever, etc. In addition, we observed petechial hemorrhages, infiltration of CD4+ cells, and increased Th2 cytokines in AHR-induced pig lungs. Ex vivo proliferated iNKT cells of asthma induced pigs in the presence of C-glycoside analogs of α-GalCer had predominant Th2 phenotype and secreted more of Th2 cytokine, IL-4. Thus, baby pigs may serve as a useful animal model to study iNKT cell-mediated AHR caused by various environmental and microbial CD1d-specific glycolipid antigens. PMID:21042929

  10. Impaired monocytic IL-10 production in sarcoidosis and potential link to abnormalities in iNKT cells

    PubMed Central

    Crawshaw, Anjali; Kendrick, Yvonne R; McMichael, Andrew J; Ho, Ling-Pei

    2016-01-01

    Sarcoidosis is a multi-system granulomatous disorder characterised by marked TH1-biased T cell expansion. The cause of T cell over-activity is unknown. We hypothesized that a cellular source for IL-10 might be defective, resulting in loss of regulation of T cell activity. Focusing on IL-10-producing monocytes, we first showed that monocytes isolated from blood of corticosteroid-naïve sarcoidosis patients (n=51) produced less IL-10 compared to controls, and were less able to suppress T cell proliferation. In addition, monocytic IL-10 production correlated negatively with disease activity. We then questioned if defects in iNKT cells (known to be reduced in sarcoidosis), might be responsible for this reduced IL-10 production since iNKT cells can interact with monocytes. We found that monocytic IL-10 production were higher where there were greater numbers of circulating iNKT cells. In vitro, iNKT cells enhanced monocytic IL-10 production. Defective IL-10 production and T cell suppression by sarcoidosis monocytes can be restored by co-culture with iNKT cells, in a CD1d-requiring and contact-dependent process. We suggest that reduced iNKT cell numbers in sarcoidosis may lead to impaired monocytic IL-10 production and unchecked T cell expansion in sarcoidosis. The findings provide fresh insight into sarcoidosis disease mechanism, and interaction between iNKT cells and monocytes. PMID:24723379

  11. Airborne lipid antigens mobilize resident intravascular NKT cells to induce allergic airway inflammation

    PubMed Central

    Scanlon, Seth T.; Thomas, Seddon Y.; Ferreira, Caroline M.; Bai, Li; Krausz, Thomas; Savage, Paul B.

    2011-01-01

    Airborne exposure to microbial cell wall lipids such as lipopolysaccharide triggers innate immune responses that regulate susceptibility to allergic airway inflammation. α-Glycosylceramides represent another widespread class of microbial lipids that directly stimulate innate-like, IL-4– and IL-13–producing, CD1d-restricted NKT cells. In this study, we demonstrate that NKT cells constitutively accumulate and reside in the microvasculature of the mouse lung. After a single airborne exposure to lipid antigen, they promptly extravasate to orchestrate the formation of peribronchiolar and interstitial lymphohistiocytic granulomas containing numerous eosinophils. Concomitant airborne exposure to ovalbumin (OVA) induces the priming of OVA-specific Th2 cells and IgE antibodies by the same dendritic cell coexpressing CD1d and MHC class II. Although NKT cell activation remains confined to the lipid-exposed lung and draining lymph nodes, Th2 cells recirculate and seed the lung of a parabiotic partner, conferring susceptibility to OVA challenge months after the initial exposure, in a manner independent of NKT cells and CD1d. Thus, transient recruitment and activation of lung-resident intravascular NKT cells can trigger long-term susceptibility to allergic airway inflammation. PMID:21930768

  12. Flagellin Modulates the Function of Invariant NKT Cells From Patients With Asthma via Dendritic Cells

    PubMed Central

    Shim, Jae-Uoong; Rhee, Joon-Haeng; Jeong, Ji-Ung

    2016-01-01

    Purpose Invariant natural killer T (iNKT) cells play a critical role in the pathogenesis of asthma. We previously reported the association between circulating Th2-like iNKT cells and lung function in asthma patients and the suppressive effect of Toll-like receptor 5 ligand flagellin B (FlaB) on asthmatic in a mouse model. Thus, we investigated whether FlaB modulates the function of circulating iNKT cells in asthmatic patients. Methods Peripheral blood mononuclear cells (PBMCs) were treated with FlaB, and the secreted and intracellular cytokines of iNKT cells were evaluated by using ELISA and flow cytometry, respectively, following stimulation with α-galactosylceramide. Foxp3+ iNKT cells were also measured. To determine the effect of FlaB-treated dendritic cells (DCs) on iNKT cells, we co-cultured CD14+ monocyte-derived DCs and T cells from patients with house dust mite-sensitive asthma and analyzed intracellular cytokines in iNKT cells. Results A reduction of IL-4 and IL-17 production by iNKT cells in PBMCs after FlaB treatment was alleviated following blocking of IL-10 signaling. A decrease in the frequencies of IL-4+ and IL-17+ iNKT cells by FlaB-treated DCs was reversed after blocking of IL-10 signaling. Simultaneously, an increase in Foxp3+ iNKT cells induced by FlaB treatment disappeared after blocking of IL-10. Conclusions FlaB may inhibit Th2- and Th17-like iNKT cells and induce Foxp3+ iNKT cells by DCs via an IL-10-dependent mechanism in asthmatic patients. In patients with a specific asthma phenotype associated with iNKT cells, FlaB may be an effective immunomodulator for iNKT cell-targeted immunotherapy. PMID:26922930

  13. Extranodal NK/T Cell Lymphoma Causing Cardiorespiratory Failure

    PubMed Central

    2016-01-01

    Extranodal NK/T cell lymphoma is an uncommon malignancy usually involving the sinonasal area. We report an unusual case of extranodal NK/T cell lymphoma diagnosed in a 62-year-old Caucasian male who died of progressive cardiorespiratory failure but had no clinically detectable upper respiratory system lesions. The initial diagnosis was made cytologically on a sample of pericardial fluid that contained neoplastic lymphoid cells. These cells were positive for CD2, cytoplasmic CD3, and Epstein-Barr virus and negative for CD56. The diagnosis was confirmed at the autopsy, which disclosed lymphoma infiltrates in the myocardium, lungs, stomach, and pancreas. The death was caused by heart and lung failure due to uncontrollable arrhythmia and respiratory insufficiency due to the lymphoma infiltrates. To the best of our knowledge, this is the first case of extranodal NK/T cell lymphoma presenting with cardiopulmonary failure. PMID:27493813

  14. Extranodal NK/T Cell Lymphoma Causing Cardiorespiratory Failure.

    PubMed

    Li, Yiting; Damjanov, Ivan

    2016-01-01

    Extranodal NK/T cell lymphoma is an uncommon malignancy usually involving the sinonasal area. We report an unusual case of extranodal NK/T cell lymphoma diagnosed in a 62-year-old Caucasian male who died of progressive cardiorespiratory failure but had no clinically detectable upper respiratory system lesions. The initial diagnosis was made cytologically on a sample of pericardial fluid that contained neoplastic lymphoid cells. These cells were positive for CD2, cytoplasmic CD3, and Epstein-Barr virus and negative for CD56. The diagnosis was confirmed at the autopsy, which disclosed lymphoma infiltrates in the myocardium, lungs, stomach, and pancreas. The death was caused by heart and lung failure due to uncontrollable arrhythmia and respiratory insufficiency due to the lymphoma infiltrates. To the best of our knowledge, this is the first case of extranodal NK/T cell lymphoma presenting with cardiopulmonary failure. PMID:27493813

  15. Antigen mRNA-transfected, allogeneic fibroblasts loaded with NKT-cell ligand confer antitumor immunity.

    PubMed

    Fujii, Shin-ichiro; Goto, Akira; Shimizu, Kanako

    2009-04-30

    The maturation of dendritic cells (DCs) in situ by danger signals plays a central role in linking innate and adaptive immunity. We previously demonstrated that the activation of invariant natural killer T (iNKT) cells by administration of alpha-galactosylceramide (alpha-GalCer)-loaded tumor cells can act as a cellular adjuvant through the DC maturation. In the current study, we used allogeneic fibroblasts loaded with alpha-GalCer and transfected with antigen-encoding mRNA, thus combining the adjuvant effects of iNKT-cell activation with delivery of antigen to DCs in vivo. We found that these cells produce antigen protein and activate NK and iNKT cells. When injected into major histocompatibility complex (MHC)-mismatched mice, they elicited antigen-specific T-cell responses and provided tumor protection, suggesting that these immune responses depend on host DCs. In addition, antigen-expressing fibroblasts loaded with alpha-GalCer lead to a more potent T-cell response than those expressing NK cell ligands. Thus, glycolipid-loaded, mRNA-transfected allogeneic fibroblasts act as cellular vectors to provide iNKT-cell activation, leading to DC maturation and T-cell immunity. By harnessing the innate immune system and generating an adaptive immune response to a variety of antigens, this unique tool could prove clinically beneficial in the development of immunotherapies against malignant and infectious diseases. PMID:19164596

  16. From the Deep Sea to Everywhere: Environmental Antigens for iNKT Cells.

    PubMed

    Wingender, Gerhard

    2016-08-01

    Invariant natural killer T (iNKT) cells are a unique subset of innate T cells that share features with innate NK cells and adaptive memory T cells. The first iNKT cell antigen described was found 1993 in a marine sponge and it took over 10 years for other, bacterial antigens to be described. Given the paucity of known bacterial iNKT cell antigens, it appeared as if iNKT cells play a very specialist role in the protection against few, rare and unusual pathogenic bacteria. However, in the last few years several publications painted a very different picture, suggesting that antigens for iNKT cells are found almost ubiquitous in the environment. These environmental iNKT cell antigens can shape the distribution, phenotype and function of iNKT cells. Here, these recent findings will be reviewed and their implications for the field will be outlined. PMID:26703211

  17. iNKT and MAIT Cell Alterations in Diabetes

    PubMed Central

    Magalhaes, Isabelle; Kiaf, Badr; Lehuen, Agnès

    2015-01-01

    Type 1 diabetes (T1D) and type 2 diabetes (T2D) are multifactorial diseases with different etiologies in which chronic inflammation takes place. Defects in invariant natural killer T (iNKT) cell populations have been reported in both T1D and T2D patients, mouse models and our recent study revealed mucosal-associated invariant T (MAIT) cell defects in T2D and obese patients. Regarding iNKT cells many studies in non-obese diabetic mice demonstrated their protective role against T1D whereas their potential role in human T1D is still under debate. Studies in mouse models and patients suggest that iNKT cells present in adipose tissue (AT) could exert a regulatory role against obesity and associated metabolic disorders, such as T2D. Scarce data are yet available on MAIT cells; however, we recently described MAIT cell abnormalities in the blood and ATs from obese and T2D patients. These data show that a link between MAIT cells and metabolic disorders pave the way for further investigations on MAIT cells in T1D and T2D in humans and mouse models. Furthermore, we hypothesize that the gut microbiota alterations associated with T1D and T2D could modulate iNKT and MAIT cell frequency and functions. The potential role of iNKT and MAIT cells in the regulation of metabolic pathways and their cross-talk with microbiota represent exciting new lines of research. PMID:26191063

  18. Invariant NKT cells regulate the CD8 T cell response during Theiler's virus infection.

    PubMed

    Mars, Lennart T; Mas, Magali; Beaudoin, Lucie; Bauer, Jan; Leite-de-Moraes, Maria; Lehuen, Agnès; Bureau, Jean-Francois; Liblau, Roland S

    2014-01-01

    Invariant NKT cells are innate lymphocytes with a broad tissue distribution. Here we demonstrate that iNKT cells reside in the central nervous system (CNS) in the absence of inflammation. Their presence in the CNS dramatically augments following inoculation of C57Bl/6 mice with the neurotropic Theiler's murine encephalomyelitis virus (TMEV). At the peak of inflammation the cellular infiltrate comprises 45,000 iNKT cells for 1250 CD8 T cells specific for the immunodominant TMEV epitope. To study the interaction between these two T cell subsets, we infected both iNKT cell deficient Jα18(-/-) mice and iNKT cell enriched Vα14 transgenic mice with TMEV. The CD8 T cell response readily cleared TMEV infection in the iNKT cell deficient mice. However, in the iNKT cell enriched mice TMEV infection persisted and was associated with significant mortality. This was caused by the inhibition of the CD8 T cell response in the cervical lymph nodes and spleen after T cell priming. Taken together we demonstrate that iNKT cells reside in the CNS in the absence of inflammation and that their enrichment is associated with the inhibition of the anti-viral CD8 T cell response and an augmented mortality during acute encephalomyelitis. PMID:24498175

  19. A humanized monoclonal antibody specific for invariant Natural Killer T (iNKT) cells for in vivo depletion.

    PubMed

    Scheuplein, Felix; Thariath, Abraham; Macdonald, Susan; Truneh, Alemseged; Mashal, Robert; Schaub, Robert

    2013-01-01

    Invariant Natural Killer T (iNKT) cells are a subset of T cells recognizing glycolipid antigens presented by CD1d. Human iNKT cells express a conserved T cell receptor (TCR)-α chain (Vα24-Jα18) paired with a specific beta chain, Vβ11. The cells are both innate-like, with rapid cytokine release, and adaptive-like, including thymic positive selection. Over activation of iNKT cells can mediate tissue injury and inflammation in multiple organ systems and play a role in mediating the pathology associated with clinically important inflammatory diseases. At the same time, iNKT cell activation can play a role in protecting against infectious disease and cancer or modulate certain autoimmune diseases through its impact on both the innate and adaptive immune system. This suggests that approaches to cause iNKT cell reduction and/or depletion could treat inflammatory diseases while approaches to promote activation may have therapeutic potential in certain infections, cancer or autoimmune disease. This report summarizes the characterization of a humanized monoclonal depleting antibody (NKTT120) in the cynomolgus macaque. NKTT120 is being developed to treat iNKT mediated inflammation that is associated with chronic inflammatory conditions like sickle cell disease and asthma. NKTT120 binds to human iTCRs and to FCγRI and FCγRIII and has been shown to kill target cells in an ADCC assay at low concentrations consistent with the FCγR binding. iNKT cells were depleted within 24 hours in cynomolgus macaques, but T cell, B cell, and NK cell frequencies were unchanged. iNKT cell recovery was dose and time dependent. T cell dependent antigen responses were not impaired by NKTT120 mediated iNKT depletion as measured by response to KLH challenge. NKTT120 administration did not induce an inflammatory cytokine release at doses up to 10 mg/kg. These data support the use of NKTT120 as an intervention in inflammatory diseases where iNKT reduction or depletion could be beneficial. PMID

  20. A Novel Glycolipid Antigen for NKT Cells That Preferentially Induces IFN-γ Production.

    PubMed

    Birkholz, Alysia M; Girardi, Enrico; Wingender, Gerhard; Khurana, Archana; Wang, Jing; Zhao, Meng; Zahner, Sonja; Illarionov, Petr A; Wen, Xiangshu; Li, Michelle; Yuan, Weiming; Porcelli, Steven A; Besra, Gurdyal S; Zajonc, Dirk M; Kronenberg, Mitchell

    2015-08-01

    In this article, we characterize a novel Ag for invariant NKT (iNKT) cells capable of producing an especially robust Th1 response. This glycosphingolipid, DB06-1, is similar in chemical structure to the well-studied α-galactosylceramide (αGalCer), with the only change being a single atom: the substitution of a carbonyl oxygen with a sulfur atom. Although DB06-1 is not a more effective Ag in vitro, the small chemical change has a marked impact on the ability of this lipid Ag to stimulate iNKT cells in vivo, with increased IFN-γ production at 24 h compared with αGalCer, increased IL-12, and increased activation of NK cells to produce IFN-γ. These changes are correlated with an enhanced ability of DB06-1 to load in the CD1d molecules expressed by dendritic cells in vivo. Moreover, structural studies suggest a tighter fit into the CD1d binding groove by DB06-1 compared with αGalCer. Surprisingly, when iNKT cells previously exposed to DB06-1 are restimulated weeks later, they have greatly increased IL-10 production. Therefore, our data are consistent with a model whereby augmented and or prolonged presentation of a glycolipid Ag leads to increased activation of NK cells and a Th1-skewed immune response, which may result, in part, from enhanced loading into CD1d. Furthermore, our data suggest that strong antigenic stimulation in vivo may lead to the expansion of IL-10-producing iNKT cells, which could counteract the benefits of increased early IFN-γ production. PMID:26078271

  1. Diacylglycerol kinase zeta positively controls the development of iNKT-17 cells.

    PubMed

    Wu, Jinhong; Shen, Shudan; Yang, Jialong; Xia, Zhenwei; Zhong, Xiao-Ping

    2013-01-01

    Invariant natural killer T (iNKT) cells play important roles in bridging innate and adaptive immunity via rapidly producing a variety of cytokines. A small subset of iNKT cells produces IL-17 and is generated in the thymus during iNKT-cell ontogeny. The mechanisms that control the development of these IL-17-producing iNKT-17 cells (iNKT-17) are still not well defined. Diacylglycerol kinase ζ (DGKζ) belongs to a family of enzymes that catalyze the phosphorylation and conversion of diacylglycerol to phosphatidic acid, two important second messengers involved in signaling from numerous receptors. We report here that DGKζ plays an important role in iNKT-17 development. A deficiency of DGKζ in mice causes a significant reduction of iNKT-17 cells, which is correlated with decreased RORγt and IL-23 receptor expression. Interestingly, iNKT-17 defects caused by DGKζ deficiency can be corrected in chimeric mice reconstituted with mixed wild-type and DGKζ-deficient bone marrow cells. Taken together, our data identify DGKζ as an important regulator of iNKT-17 development through iNKT-cell extrinsic mechanisms. PMID:24073253

  2. Regulated Expression of miR-155 is Required for iNKT Cell Development

    PubMed Central

    Burocchi, Alessia; Pittoni, Paola; Tili, Esmerina; Rigoni, Alice; Costinean, Stefan; Croce, Carlo Maria; Colombo, Mario Paolo

    2015-01-01

    Invariant natural killer T cells (iNKT cells) are CD1d-restricted, lipid antigen-reactive T lymphocytes with immunoregulatory functions. iNKT cell development in the thymus proceeds through subsequent stages, defined by the expression of CD44 and NK1.1, and is dictated by a unique gene expression program, including microRNAs. Here, we investigated whether miR-155, a microRNA involved in differentiation of most hematopoietic cells, played any role in iNKT cell development. To this end, we assessed the expression of miR-155 along iNKT cell maturation in the thymus, and studied the effects of miR-155 on iNKT cell development using Lck-miR-155 transgenic mice, which over express miR-155 in T cell lineage under the lymphocyte-specific protein tyrosine kinase (Lck) promoter. We show that miR-155 is expressed by newly selected immature wild-type iNKT cells and turned off along iNKT cells differentiation. In transgenic mice, miR-155 over-expression resulted in a substantial block of iNKT cell maturation at Stage 2, in the thymus toward an overall reduction of peripheral iNKT cells, unlike mainstream T cells. Furthermore, the effects of miR-155 over-expression on iNKT cell differentiation were cell autonomous. Finally, we identified Ets1 and ITK transcripts as relevant targets of miR-155 in iNKT cell differentiation. Altogether, these results demonstrate that a tight control of miR-155 expression is required for the development of iNKT cells. PMID:25870598

  3. Raising the Roof: The Preferential Pharmacological Stimulation of Th1 and Th2 Responses Mediated by NKT Cells

    PubMed Central

    East, James E.; Kennedy, Andrew J.; Webb, Tonya J.

    2014-01-01

    Natural killer T (NKT) cells serve as a bridge between the innate and adaptive immune systems, and manipulating their effector functions can have therapeutic significances in the treatment of autoimmunity, transplant biology, infectious disease, and cancer. NKT cells are a subset of T cells that express cell-surface markers characteristic of both natural killer cells and T cells. These unique immunologic cells have been demonstrated to serve as a link between the innate and adaptive immune systems through their potent cytokine production following the recognition of a range of lipid antigens, mediated through presentation of the major histocompatibility complex (MHC) class I like CD1d molecule, in addition to the NKT cell′s cytotoxic capabilities upon activation. Although a number of glycolipid antigens have been shown to complex with CD1d molecules, most notably the marine sponge derived glycolipid alpha-galactosylceramide (α-GalCer), there has been debate as to the identity of the endogenous activating lipid presented to the T-cell receptor (TCR) via the CD1d molecule on antigen-presenting cells (APCs). This review aims to survey the use of pharmacological agents and subsequent structure–activity relationships (SAR) that have given insight into the binding interaction of glycolipids with both the CD1d molecules as well as the TCR and the subsequent immunologic response of NKT cells. These studies not only elucidate basic binding interactions but also pave the way for future pharmacological modulation of NKT cell responses. PMID:23239102

  4. Role of NK, NKT cells and macrophages in liver transplantation

    PubMed Central

    Fahrner, René; Dondorf, Felix; Ardelt, Michael; Settmacher, Utz; Rauchfuss, Falk

    2016-01-01

    Liver transplantation has become the treatment of choice for acute or chronic liver disease. Because the liver acts as an innate immunity-dominant organ, there are immunological differences between the liver and other organs. The specific features of hepatic natural killer (NK), NKT and Kupffer cells and their role in the mechanism of liver transplant rejection, tolerance and hepatic ischemia-reperfusion injury are discussed in this review. PMID:27468206

  5. Dendritic cells and anergic type I NKT cells play a crucial role in sulfatide-mediated immune regulation in experimental autoimmune encephalomyelitis

    PubMed Central

    Maricic, Igor; Halder, Ramesh; Bischof, Felix; Kumar, Vipin

    2014-01-01

    CD1d-restricted NKT cells can be divided into two groups: type I NKT cells utilize a semi-invariant TCR whereas type II express a relatively diverse set of TCRs. A major subset of type II NKT cells recognizes myelin-derived sulfatides and is selectively enriched in the central nervous system tissue during experimental autoimmune encephalomyelitis (EAE). We have shown that activation of sulfatide-reactive type II NKT cells by sulfatide prevents induction of EAE. Here we have addressed the mechanism of regulation as well as whether a single immunodominant form of synthetic sulfatide can treat ongoing chronic and relapsing EAE in SJL/J mice. We have shown that the activation of sulfatide-reactive type II NKT cells leads to a significant reduction in the frequency and effector function of PLP139-151/I-As–tetramer+ cells in lymphoid and CNS tissues. In addition, type I NKT cells and dendritic cells in the periphery as well as CNS-resident microglia are inactivated following sulfatide administration, and mice deficient in type I NKT cells are not protected from disease. Moreover tolerized DCs from sulfatide-treated animals can adoptively transfer protection into naive mice. Treatment of SJL/J mice with a synthetic cis-tetracosenoyl sulfatide, but not αGalCer, reverses ongoing chronic and relapsing EAE. Our data highlight a novel immune regulatory pathway involving NKT subset interactions leading to inactivation of type I NKT cells, DCs, and microglial cells in suppression of autoimmunity. Since CD1 molecules are non-polymorphic, the sulfatide-mediated immune regulatory pathway can be targeted for development of non-HLA-dependent therapeutic approaches to T cell-mediated autoimmune diseases. PMID:24973441

  6. Co-administration of α-GalCer analog and TLR4 agonist induces robust CD8(+) T-cell responses to PyCS protein and WT-1 antigen and activates memory-like effector NKT cells.

    PubMed

    Coelho-Dos-Reis, Jordana G; Huang, Jing; Tsao, Tiffany; Pereira, Felipe V; Funakoshi, Ryota; Nakajima, Hiroko; Sugiyama, Haruo; Tsuji, Moriya

    2016-07-01

    In the present study, the combined adjuvant effect of 7DW8-5, a potent α-GalCer-analog, and monophosphoryl lipid A (MPLA), a TLR4 agonist, on the induction of vaccine-induced CD8(+) T-cell responses and protective immunity was evaluated. Mice were immunized with peptides corresponding to the CD8(+) T-cell epitopes of a malaria antigen, a circumsporozoite protein of Plasmodium yoelii, and a tumor antigen, a Wilms Tumor antigen-1 (WT-1), together with 7DW8-5 and MPLA, as an adjuvant. These immunization regimens were able to induce higher levels of CD8(+) T-cell responses and, ultimately, enhanced levels of protection against malaria and tumor challenges compared to the levels induced by immunization with peptides mixed with 7DW8-5 or MPLA alone. Co-administration of 7DW8-5 and MPLA induces activation of memory-like effector natural killer T (NKT) cells, i.e. CD44(+)CD62L(-)NKT cells. Our study indicates that 7DW8-5 greatly enhances important synergistic pathways associated to memory immune responses when co-administered with MPLA, thus rendering this combination of adjuvants a novel vaccine adjuvant formulation. PMID:27132023

  7. Co-administration of α-GalCer analog and TLR4 agonist induces robust CD8+ T-cell responses to PyCS protein and WT-1 antigen and activates memory-like effector NKT cells

    PubMed Central

    Coelho-dos-Reis, Jordana G.; Huang, Jing; Tsao, Tiffany; Pereira, Felipe V.; Funakoshi, Ryota; Nakajima, Hiroko; Sugiyama, Haruo; Tsuji, Moriya

    2016-01-01

    In the present study, the combined adjuvant effect of 7DW8-5, a potent α-GalCer-analog, and monophosphoryl lipid A (MPLA), a TLR4 agonist, on the induction of vaccine-induced CD8+ T-cell responses and protective immunity was evaluated. Mice were immunized with peptides corresponding to the CD8+ T-cell epitopes of a malaria antigen, a circumsporozoite protein of Plasmodium yoelii, and a tumor antigen, a Wilms Tumor antigen-1 (WT-1), together with 7DW8-5 and MPLA, as an adjuvant. These immunization regimens were able to induce higher levels of CD8+ T-cell responses and, ultimately, enhanced levels of protection against malaria and tumor challenges compared to the levels induced by immunization with peptides mixed with 7DW8-5 or MPLA alone. Co-administration of 7DW8-5 and MPLA induces activation of memory-like effector natural killer T (NKT) cells, i.e. CD44+CD62L−NKT cells. Our study indicates that 7DW8-5 greatly enhances important synergistic pathways associated to memory immune responses when co-administered with MPLA, thus rendering this combination of adjuvants a novel vaccine adjuvant formulation. PMID:27132023

  8. Innate Invariant NKT Cell Recognition of HIV-1-Infected Dendritic Cells Is an Early Detection Mechanism Targeted by Viral Immune Evasion.

    PubMed

    Paquin-Proulx, Dominic; Gibbs, Anna; Bächle, Susanna M; Checa, Antonio; Introini, Andrea; Leeansyah, Edwin; Wheelock, Craig E; Nixon, Douglas F; Broliden, Kristina; Tjernlund, Annelie; Moll, Markus; Sandberg, Johan K

    2016-09-01

    Invariant NKT (iNKT) cells are innate-like T cells that respond rapidly with a broad range of effector functions upon recognition of glycolipid Ags presented by CD1d. HIV-1 carries Nef- and Vpu-dependent mechanisms to interfere with CD1d surface expression, indirectly suggesting a role for iNKT cells in control of HIV-1 infection. In this study, we investigated whether iNKT cells can participate in the innate cell-mediated immune response to HIV-1. Infection of dendritic cells (DCs) with Nef- and Vpu-deficient HIV-1 induced upregulation of CD1d in a TLR7-dependent manner. Infection of DCs caused modulation of enzymes in the sphingolipid pathway and enhanced expression of the endogenous glucosylceramide Ag. Importantly, iNKT cells responded specifically to rare DCs productively infected with Nef- and Vpu-defective HIV-1. Transmitted founder viral isolates differed in their CD1d downregulation capacity, suggesting that diverse strains may be differentially successful in inhibiting this pathway. Furthermore, both iNKT cells and DCs expressing CD1d and HIV receptors resided in the female genital mucosa, a site where HIV-1 transmission occurs. Taken together, these findings suggest that innate iNKT cell sensing of HIV-1 infection in DCs is an early immune detection mechanism, which is independent of priming and adaptive recognition of viral Ag, and is actively targeted by Nef- and Vpu-dependent viral immune evasion mechanisms. PMID:27481843

  9. Innate Invariant NKT Cell Recognition of HIV-1–Infected Dendritic Cells Is an Early Detection Mechanism Targeted by Viral Immune Evasion

    PubMed Central

    Paquin-Proulx, Dominic; Gibbs, Anna; Bächle, Susanna M.; Checa, Antonio; Introini, Andrea; Leeansyah, Edwin; Wheelock, Craig E.; Nixon, Douglas F.; Broliden, Kristina; Tjernlund, Annelie; Moll, Markus

    2016-01-01

    Invariant NKT (iNKT) cells are innate-like T cells that respond rapidly with a broad range of effector functions upon recognition of glycolipid Ags presented by CD1d. HIV-1 carries Nef- and Vpu-dependent mechanisms to interfere with CD1d surface expression, indirectly suggesting a role for iNKT cells in control of HIV-1 infection. In this study, we investigated whether iNKT cells can participate in the innate cell–mediated immune response to HIV-1. Infection of dendritic cells (DCs) with Nef- and Vpu-deficient HIV-1 induced upregulation of CD1d in a TLR7-dependent manner. Infection of DCs caused modulation of enzymes in the sphingolipid pathway and enhanced expression of the endogenous glucosylceramide Ag. Importantly, iNKT cells responded specifically to rare DCs productively infected with Nef- and Vpu-defective HIV-1. Transmitted founder viral isolates differed in their CD1d downregulation capacity, suggesting that diverse strains may be differentially successful in inhibiting this pathway. Furthermore, both iNKT cells and DCs expressing CD1d and HIV receptors resided in the female genital mucosa, a site where HIV-1 transmission occurs. Taken together, these findings suggest that innate iNKT cell sensing of HIV-1 infection in DCs is an early immune detection mechanism, which is independent of priming and adaptive recognition of viral Ag, and is actively targeted by Nef- and Vpu-dependent viral immune evasion mechanisms. PMID:27481843

  10. CDR3β sequence motifs regulate autoreactivity of human invariant NKT cell receptors.

    PubMed

    Chamoto, Kenji; Guo, Tingxi; Imataki, Osamu; Tanaka, Makito; Nakatsugawa, Munehide; Ochi, Toshiki; Yamashita, Yuki; Saito, Akiko M; Saito, Toshiki I; Butler, Marcus O; Hirano, Naoto

    2016-04-01

    Invariant natural killer T (iNKT) cells are a subset of T lymphocytes that recognize lipid ligands presented by monomorphic CD1d. Human iNKT T cell receptor (TCR) is largely composed of invariant Vα24 (Vα24i) TCRα chain and semi-variant Vβ11 TCRβ chain, where complementarity-determining region (CDR)3β is the sole variable region. One of the characteristic features of iNKT cells is that they retain autoreactivity even after the thymic selection. However, the molecular features of human iNKT TCR CDR3β sequences that regulate autoreactivity remain unknown. Since the numbers of iNKT cells with detectable autoreactivity in peripheral blood is limited, we introduced the Vα24i gene into peripheral T cells and generated a de novo human iNKT TCR repertoire. By stimulating the transfected T cells with artificial antigen presenting cells (aAPCs) presenting self-ligands, we enriched strongly autoreactive iNKT TCRs and isolated a large panel of human iNKT TCRs with a broad range autoreactivity. From this panel of unique iNKT TCRs, we deciphered three CDR3β sequence motifs frequently encoded by strongly-autoreactive iNKT TCRs: a VD region with 2 or more acidic amino acids, usage of the Jβ2-5 allele, and a CDR3β region of 13 amino acids in length. iNKT TCRs encoding 2 or 3 sequence motifs also exhibit higher autoreactivity than those encoding 0 or 1 motifs. These data facilitate our understanding of the molecular basis for human iNKT cell autoreactivity involved in immune responses associated with human disease. PMID:26748722

  11. Non‐glycosidic compounds can stimulate both human and mouse iNKT cells

    PubMed Central

    Jukes, John‐Paul; Gileadi, Uzi; Ghadbane, Hemza; Yu, Ting‐Fong; Shepherd, Dawn; Cox, Liam R.; Besra, Gurdyal S.

    2016-01-01

    Invariant natural killer T (iNKT) cells recognize CD1d/glycolipid complexes and upon activation with synthetic agonists display immunostimulatory properties. We have previously described that the non‐glycosidic CD1d‐binding lipid, threitolceramide (ThrCer) activates murine and human iNKT cells. Here, we show that incorporating the headgroup of ThrCer into a conformationally more restricted 6‐ or 7‐membered ring results in significantly more potent non‐glycosidic analogs. In particular, ThrCer 6 was found to promote strong anti‐tumor responses and to induce a more prolonged stimulation of iNKT cells than does the canonical α‐galactosylceramide (α‐GalCer), achieving an enhanced T‐cell response at lower concentrations compared with α‐GalCer both in vitro, using human iNKT‐cell lines and in vivo, using C57BL/6 mice. Collectively, these studies describe novel non‐glycosidic ThrCer‐based analogs that have improved potency in iNKT‐cell activation compared with that of α‐GalCer, and are clinically relevant iNKT‐cell agonists. PMID:26873393

  12. Regulation of NKT cell-mediated immune responses to tumours and liver inflammation by mitochondrial PGAM5-Drp1 signalling

    PubMed Central

    Kang, Young Jun; Bang, Bo-Ram; Han, Kyung Ho; Hong, Lixin; Shim, Eun-Jin; Ma, Jianhui; Lerner, Richard A.; Otsuka, Motoyuki

    2015-01-01

    The receptor-interacting protein kinase 3 (RIPK3) plays crucial roles in programmed necrosis and innate inflammatory responses. However, a little is known about the involvement of RIPK3 in NKT cell-mediated immune responses. Here, we demonstrate that RIPK3 plays an essential role in NKT cell function via activation of the mitochondrial phosphatase phosphoglycerate mutase 5 (PGAM5). RIPK3-mediated activation of PGAM5 promotes the expression of cytokines by facilitating nuclear translocation of NFAT and dephosphorylation of dynamin-related protein 1 (Drp1), a GTPase is essential for mitochondrial homoeostasis. Ripk3−/− mice show reduced NKT cell responses to metastatic tumour cells, and both deletion of RIPK3 and pharmacological inhibition of Drp1 protects mice from NKT cell-mediated induction of acute liver damage. Collectively, the results identify a crucial role for RIPK3-PGAM5-Drp1/NFAT signalling in NKT cell activation, and further suggest that RIPK3-PGAM5 signalling may mediate crosstalk between mitochondrial function and immune signalling. PMID:26381214

  13. The Extended Family of CD1d-Restricted NKT Cells: Sifting through a Mixed Bag of TCRs, Antigens, and Functions

    PubMed Central

    Macho-Fernandez, Elodie; Brigl, Manfred

    2015-01-01

    Natural killer T (NKT) cells comprise a family of specialized T cells that recognize lipid antigens presented by CD1d. Based on their T cell receptor (TCR) usage and antigen specificities, CD1d-restricted NKT cells have been divided into two main subsets: type I NKT cells that use a canonical invariant TCR α-chain and recognize α-galactosylceramide (α-GalCer), and type II NKT cells that use a more diverse αβ TCR repertoire and do not recognize α-GalCer. In addition, α-GalCer-reactive NKT cells that use non-canonical αβ TCRs and CD1d-restricted T cells that use γδ or δ/αβ TCRs have recently been identified, revealing further diversity among CD1d-restricted T cells. Importantly, in addition to their distinct antigen specificities, functional differences are beginning to emerge between the different members of the CD1d-restricted T cell family. In this review, while using type I NKT cells as comparison, we will focus on type II NKT cells and the other non-invariant CD1d-restricted T cell subsets, and discuss our current understanding of the antigens they recognize, the formation of stimulatory CD1d/antigen complexes, the modes of TCR-mediated antigen recognition, and the mechanisms and consequences of their activation that underlie their function in antimicrobial responses, anti-tumor immunity, and autoimmunity. PMID:26284062

  14. A novel glycolipid antigen for NKT cells that preferentially induces IFN-γ production

    PubMed Central

    Birkholz, Alysia M.; Girardi, Enrico; Wingender, Gerhard; Khurana, Archana; Wang, Jing; Zhao, Meng; Zahner, Sonja; Illarionov, Petr A.; Wen, Xiangshu; Li, Michelle; Yuan, Weiming; Porcelli, Steven A.; Besra, Gurdyal S.; Zajonc, Dirk M.; Kronenberg, Mitchell

    2015-01-01

    Here we characterize a novel Ag for invariant natural killer T-cells (iNKT cells) capable of producing an especially robust Th1 response. This glycosphingolipid (GSL), DB06-1, is similar in chemical structure to the well-studied α-galactosylceramide (αGalCer), the only change being in a single atom, the substitution of a carbonyl oxygen with a sulfur atom. Although DB06-1 is not a more effective Ag in vitro, the small chemical change has a marked impact on the ability of this lipid Ag to stimulate iNKT cells in vivo, with increased IFN-γ production at 24 h compared to αGalCer, increased IL-12, and increased activation of NK cells to produce IFN-γ. These changes are correlated with an enhanced ability of DB06-1 to load in the CD1d molecules expressed by DCs in vivo. Moreover, structural studies suggest a tighter fit into the CD1d binding groove by DB061 compared to αGalCer. Surprisingly, when iNKT cells previously exposed to DB06-1 are restimulated weeks later, they have greatly increased IL-10 production. Our data are therefore consistent with a model whereby augmented and or prolonged presentation of a glycolipid Ag leads to increased activation of NK cells and a Th1-skewed immune response, which may result in part from enhanced loading into CD1d. Furthermore, our data suggest that strong antigenic stimulation in vivo may lead to the expansion of IL-10 producing iNKT cells, which could counteract the benefits of increased, early IFN-γ production. PMID:26078271

  15. Cellular Adjuvant Properties, Direct Cytotoxicity of Re-differentiated Vα24 Invariant NKT-like Cells from Human Induced Pluripotent Stem Cells

    PubMed Central

    Kitayama, Shuichi; Zhang, Rong; Liu, Tian-Yi; Ueda, Norihiro; Iriguchi, Shoichi; Yasui, Yutaka; Kawai, Yohei; Tatsumi, Minako; Hirai, Norihito; Mizoro, Yasutaka; Iwama, Tatsuaki; Watanabe, Akira; Nakanishi, Mahito; Kuzushima, Kiyotaka; Uemura, Yasushi; Kaneko, Shin

    2016-01-01

    Summary Vα24 invariant natural killer T (iNKT) cells are a subset of T lymphocytes implicated in the regulation of broad immune responses. They recognize lipid antigens presented by CD1d on antigen-presenting cells and induce both innate and adaptive immune responses, which enhance effective immunity against cancer. Conversely, reduced iNKT cell numbers and function have been observed in many patients with cancer. To recover these numbers, we reprogrammed human iNKT cells to pluripotency and then re-differentiated them into regenerated iNKT cells in vitro through an IL-7/IL-15-based optimized cytokine combination. The re-differentiated iNKT cells showed proliferation and IFN-γ production in response to α-galactosylceramide, induced dendritic cell maturation and downstream activation of both cytotoxic T lymphocytes and NK cells, and exhibited NKG2D- and DNAM-1-mediated NK cell-like cytotoxicity against cancer cell lines. The immunological features of re-differentiated iNKT cells and their unlimited availability from induced pluripotent stem cells offer a potentially effective immunotherapy against cancer. PMID:26862702

  16. Protection Against Type 1 Diabetes Upon Coxsackievirus B4 Infection and iNKT-Cell Stimulation

    PubMed Central

    Ghazarian, Liana; Diana, Julien; Beaudoin, Lucie; Larsson, Pär G.; Puri, Raj K.; van Rooijen, Nico; Flodström-Tullberg, Malin; Lehuen, Agnès

    2013-01-01

    Invariant natural killer T (iNKT) cells belong to the innate immune system and exercise a dual role as potent regulators of autoimmunity and participate in responses against different pathogens. They have been shown to prevent type 1 diabetes development and to promote antiviral responses. Many studies in the implication of environmental factors on the etiology of type 1 diabetes have suggested a link between enteroviral infections and the development of this disease. This study of the pancreatropic enterovirus Coxsackievirus B4 (CVB4) shows that although infection accelerated type 1 diabetes development in a subset of proinsulin 2–deficient NOD mice, the activation of iNKT cells by a specific agonist, α-galactosylceramide, at the time of infection inhibited the disease. Diabetes development was associated with the infiltration of pancreatic islets by inflammatory macrophages, producing high levels of interleukin (IL)-1β, IL-6, and tumor necrosis factor-α and activation of anti-islet T cells. On the contrary, macrophages infiltrating the islets after CVB4 infection and iNKT-cell stimulation expressed a number of suppressive enzymes, among which indoleamine 2,3-dioxygenase was sufficient to inhibit anti-islet T-cell response and to prevent diabetes. This study highlights the critical interaction between virus and the immune system in the acceleration or prevention of type 1 diabetes. PMID:23894189

  17. Abnormalities in iNKT cells are associated with impaired ability of monocytes to produce IL-10 and suppress T-cell proliferation in sarcoidosis.

    PubMed

    Crawshaw, Anjali; Kendrick, Yvonne R; McMichael, Andrew J; Ho, Ling-Pei

    2014-07-01

    Sarcoidosis is a multisystem granulomatous disorder characterized by marked T-cell expansion of T helper 1 (Th1) cells. The cause of T-cell overactivity is unknown. We hypothesized that interleukin-10 (IL-10) production by a yet undefined cell type might be defective, resulting in loss of regulation of T-cell activity. Focusing on IL-10-producing monocytes, we first showed that monocytes isolated from the peripheral blood of corticosteroid-naïve sarcoidosis patients (n = 51) produced less IL-10 compared to controls, and were less able to suppress T-cell proliferation. In addition, monocytic IL-10 production correlated negatively with disease activity score. As invariant natural killer T (iNKT) cells are known to both interact with monocytes and be reduced in sarcoidosis patients, we then asked whether iNKT-specific defects might be responsible for this reduced IL-10 production. We found that greater numbers of circulating iNKT cells was associated with higher IL-10 production. Moreover, iNKT cells enhanced monocytic IL-10 production in vitro. Defective IL-10 production and T-cell suppression by sarcoidosis monocytes could be restored following their coculture with iNKT cells, in a CD1d- and cell contact-dependent process. We suggest that reduced iNKT-cell numbers in sarcoidosis may lead to impaired monocytic IL-10 production and unchecked T-cell expansion in sarcoidosis. These findings provide fresh insight into the mechanism of sarcoidosis disease, and interaction between iNKT cells and monocytes. PMID:24723379

  18. The cytokine profile of human NKT cells and PBMCs is dependent on donor sex and stimulus.

    PubMed

    Bernin, Hannah; Fehling, Helena; Marggraff, Claudia; Tannich, Egbert; Lotter, Hannelore

    2016-08-01

    Sex-related variations in natural killer T (NKT) cells may influence immunoregulation and outcome of infectious and autoimmune diseases. We analyzed sex-specific differences in peripheral blood NKTs and peripheral blood mononuclear cells (PBMCs) from men and women and determined the frequencies of NKT cells and their subpopulations [CD4(+); CD8(+); double negative (DN)] and the levels of cytokine production following stimulation with the NKT cell ligands α-Galactosylceramide (αGalCer) and Entamoeba histolytica lipopeptidephosphoglycan (Lotter et al. in PLoS Pathog 5(5):e1000434, 2009). Total and DN NKT cells were more abundant in women than in men. In women, αGalCer induced higher production of intracellular IFNγ, IL-4, IL-17 and TNF by CD4(+) and DN(+)NKT cells. Both ligands induced expression of multiple cytokines in PBMCs and influenced the ratio of NKT cell subpopulations during long-term culture. Although the sex-specific differences in frequencies of NKT cells and their subpopulations were marginal, the significant sex-specific differences in cytokine production might influence disease outcomes. PMID:26895635

  19. NKT cell stimulation with glycolipid antigen in vivo: co-stimulation-dependent expansion, Bim-dependent contraction, and hypo-responsiveness to further antigenic challenge1

    PubMed Central

    Kyparissoudis, Konstantinos; Pellicci, Daniel G.; Zhan, Yifan; Lew, Andrew M.; Bouillet, Philippe; Strasser, Andreas; Smyth, Mark J.; Godfrey, Dale I.

    2005-01-01

    Activation of NKT cells using the glycolipid α-galactosylceramide (α-GalCer4) has availed many investigations into their immunoregulatory and therapeutic potential. However, it remains unclear how NKT cells respond to stimulation in vivo, which co-stimulatory pathways are important, and what factors (eg. antigen availability and activation-induced cell death) limit their response. We have explored these questions in the context of anin vivo model of NKT cell dynamics spanning activation, population expansion and subsequent contraction. Neither the B7/CD28 nor the CD40/CD40-L co-stimulatory pathways were necessary for cytokine production by activated NKT cells, either early (2 hours) or late (3 days) following initial stimulation, but both pathways were necessary for normal proliferative expansion of NKT cells in vivo. The pro-apoptotic Bcl-2 family member Bim was necessary for normal contraction of the NKT cell population between days 3-9 after stimulation, suggesting the pool size is regulated by apoptotic cell death in a manner similar to that of conventional T cells. Antigen availability was not the limiting factor for NKT cell expansion in vivo, and a second injection of α-GalCer induced a very blunted response, whereby cytokine production was reduced and further expansion did not occur. This appeared to be a form of anergy that was intrinsic to the NKT cells and not associated with up-regulation of inhibitory NK cell receptors such as NKG2A or Ly49 family members. Furthermore, NKT cells from mice pre-challenged with α-GalCer in vivoshowed little cytokine production and reduced proliferation in vitro. In summary, this study significantly enhances our understanding of how NKT cells respond to α-GalCer in vivo, revealing that the full primary response depends on costimulation via the CD28 and CD40 pathways, with subsequent Bim-dependent contraction. After contraction, the NKT cells are hypo-responsive to further antigenic induced expansion. PMID:16116198

  20. T cell receptor signal strength in Treg and iNKT cell development demonstrated by a novel fluorescent reporter mouse

    PubMed Central

    Moran, Amy E.; Holzapfel, Keli L.; Xing, Yan; Cunningham, Nicole R.; Maltzman, Jonathan S.; Punt, Jennifer

    2011-01-01

    The ability of antigen receptors to engage self-ligands with varying affinity is crucial for lymphocyte development. To further explore this concept, we generated transgenic mice expressing GFP from the immediate early gene Nr4a1 (Nur77) locus. GFP was up-regulated in lymphocytes by antigen receptor stimulation but not by inflammatory stimuli. In T cells, GFP was induced during positive selection, required major histocompatibility complex for maintenance, and directly correlated with the strength of T cell receptor (TCR) stimulus. Thus, our results define a novel tool for studying antigen receptor activation in vivo. Using this model, we show that regulatory T cells (Treg cells) and invariant NKT cells (iNKT cells) perceived stronger TCR signals than conventional T cells during development. However, although Treg cells continued to perceive strong TCR signals in the periphery, iNKT cells did not. Finally, we show that Treg cell progenitors compete for recognition of rare stimulatory TCR self-ligands. PMID:21606508

  1. NKT cells mediate pulmonary inflammation and dysfunction in murine sickle cell disease through production of IFN-γ and CXCR3 chemokines

    PubMed Central

    Wallace, Kori L.; Marshall, Melissa A.; Ramos, Susan I.; Lannigan, Joanne A.; Field, Joshua J.; Strieter, Robert M.

    2009-01-01

    Ischemia-reperfusion injury (IRI) triggers an inflammatory cascade that is initiated by the activation of CD1d-restricted iNKT cells. In sickle cell disease (SCD), misshapen erythrocytes evoke repeated transient bouts of microvascular IRI. Compared with C57BL/6 controls, NY1DD mice have more numerous and activated (CD69+, interferon-γ+ [IFN-γ+]) lung, liver, and spleen iNKT cells that are hyperresponsive to hypoxia/reoxygenation. NY1DD mice have increased pulmonary levels of IFN-γ, IFN-γ–inducible chemokines (CXCL9, CXCL10), and elevated numbers of lymphocytes expressing the chemokine receptor CXCR3. Treating NY1DD mice with anti-CD1d antibody to inhibit iNKT cell activation reverses baseline pulmonary dysfunction manifested as elevated vascular permeability, decreased arterial oxygen saturation, and increased numbers of activated leukocytes. Anti-CD1d antibodies decrease pulmonary levels of IFN-γ and CXCR3 chemokines. Neutralization of CXCR3 receptors ameliorates pulmonary dysfunction. Crossing NY1DD to lymphocyte-deficient Rag1−/− mice decreases pulmonary dysfunction. This is counteracted by the adoptive transfer of 1 million NKT cells. Like mice, people with SCD have increased numbers of activated circulating iNKT cells expressing CXCR3. Together, these data indicate that iNKT cells play a pivotal role in sustaining inflammation in SCD mice by a pathway involving IFN-γ and production of chemotactic CXCR3 chemokines and that this mechanism may translate to human disease. PMID:19433855

  2. Restored Circulating Invariant NKT Cells Are Associated with Viral Control in Patients with Chronic Hepatitis B

    PubMed Central

    Jiang, Xiaotao; Zhang, Mingxia; Lai, Qintao; Huang, Xuan; Li, Yongyin; Sun, Jian; Abbott, William G.H.; Ma, Shiwu; Hou, Jinlin

    2011-01-01

    Invariant NKT (iNKT) cells are involved in the pathogenesis of various infectious diseases. However, their role in hepatitis B virus (HBV) infection is not fully understood, especially in human species. In this study, 35 chronic hepatitis B (CHB) patients, 25 inactive carriers (IC) and 36 healthy controls (HC) were enrolled and the proportions of circulating iNKT cells in fresh isolated peripheral blood mononuclear cells (PBMC) were detected by flow cytometry. A longitudinal analysis was also conducted in 19 CHB patients who received antiviral therapy with telbivudine. Thereafter, the immune functions of iNKT cells were evaluated by cytokine secretion and a two-chamber technique. The median frequency of circulating iNKT cells in CHB patients (0.13%) was lower than that in HC (0.24%, P = 0.01) and IC (0.19%, P = 0.02), and increased significantly during antiviral therapy with telbivudine (P = 0.0176). The expressions of CC chemokine receptor 5 (CCR5) and CCR6 were dramatically higher on iNKT cells (82.83%±9.87%, 67.67%±16.83% respectively) than on conventional T cells (30.5%±5.65%, 14.02%±5.92%, both P<0.001) in CHB patients. Furthermore, iNKT cells could migrate toward the CC chemokine ligand 5. Patients with a high ratio (≥1.0) of CD4−/CD4+ iNKT cells at baseline had a higher rate (58.33%) of HBeAg seroconversion than those with a low ratio (<1.0, 0%, P = 0.0174). In conclusion, there is a low frequency of peripheral iNKT cells in CHB patients, which increases to normal levels with viral control. The ratio of CD4−/CD4+ iNKT cells at baseline may be a useful predictor for HBeAg seroconversion in CHB patients on telbivudine therapy. PMID:22194934

  3. Exploiting the Role of Endogenous Lymphoid-Resident Dendritic Cells in the Priming of NKT Cells and CD8+ T Cells to Dendritic Cell-Based Vaccines

    PubMed Central

    Petersen, Troels R.; Sika-Paotonu, Dianne; Knight, Deborah A.; Simkins, Helen M. A.; Hermans, Ian F.

    2011-01-01

    Transfer of antigen between antigen-presenting cells (APCs) is potentially a physiologically relevant mechanism to spread antigen to cells with specialized stimulatory functions. Here we show that specific CD8+ T cell responses induced in response to intravenous administration of antigen-loaded bone marrow-derived dendritic cells (BM-DCs), were ablated in mice selectively depleted of endogenous lymphoid-resident langerin+ CD8α+ dendritic cells (DCs), suggesting that the antigen is transferred from the injected cells to resident APCs. In contrast, antigen-specific CD4+ T cells were primed predominantly by the injected BM-DCs, with only very weak contribution of resident APCs. Crucially, resident langerin+ CD8α+ DCs only contributed to the priming of CD8+ T cells in the presence of maturation stimuli such as intravenous injection of TLR ligands, or by loading the BM-DCs with the glycolipid α-galactosylceramide (α-GalCer) to recruit the adjuvant activity of activated invariant natural killer-like T (iNKT) cells. In fact, injection of α-GalCer-loaded CD1d−/− BM-DCs resulted in potent iNKT cell activation, suggesting that this glycolipid antigen can also be transferred to resident CD1d+ APCs. While iNKT cell activation per se was independent of langerin+ CD8α+ DCs, some iNKT cell-mediated activities were reduced, notably release of IL-12p70 and transactivation of NK cells. We conclude that both protein and glycolipid antigens can be exchanged between distinct DC species. These data suggest that the efficacy of DC-based vaccination strategies may be improved by the incorporation of a systemic maturation signal aimed to engage resident APCs in CD8+ T cell priming, and α-GalCer may be particularly well suited to this purpose. PMID:21483862

  4. Adenosine A2A receptors induced on iNKT and NK cells reduce pulmonary inflammation and injury in mice with sickle cell disease

    PubMed Central

    Wallace, Kori L.

    2010-01-01

    We showed previously that pulmonary function and arterial oxygen saturation in NY1DD mice with sickle cell disease (SCD) are improved by depletion of invariant natural killer T (iNKT) cells or blockade of their activation. Here we demonstrate that SCD causes a 9- and 6-fold induction of adenosine A2A receptor (A2AR) mRNA in mouse pulmonary iNKT and natural killer (NK) cells, respectively. Treating SCD mice with the A2AR agonist ATL146e produced a dose-dependent reversal of pulmonary dysfunction with maximal efficacy at 10 ng/kg/minute that peaked within 3 days and persisted throughout 7 days of continuous infusion. Crossing NY1DD mice with Rag1−/− mice reduced pulmonary injury that was restored by adoptive transfer of 106 purified iNKT cells. Reconstituted injury was reversed by ATL146e unless the adoptively transferred iNKT cells were pretreated with the A2AR alkylating antagonist, FSPTP (5-amino-7-[2-(4-fluorosulfonyl)phenylethyl]-2-(2-furyl)-pryazolo[4,3-ϵ]-1,2,4-triazolo[1,5-c]pyrimidine), which completely prevented pro-tection. In NY1DD mice exposed to hypoxia-reoxygenation, treatment with ATL146e at the start of reoxygenation prevented further lung injury. Together, these data indicate that activation of induced A2ARs on iNKT and NK cells in SCD mice is sufficient to improve baseline pulmonary function and prevent hypoxia-reoxygenation–induced exacerbation of pulmonary injury. A2A agonists have promise for treating diseases associated with iNKT or NK cell activation. PMID:20798237

  5. An efferocytosis-induced, IL-4–dependent macrophage-iNKT cell circuit suppresses sterile inflammation and is defective in murine CGD

    PubMed Central

    Zeng, Melody Yue; Pham, Duy; Bagaitkar, Juhi; Liu, Jianyun; Otero, Karel; Shan, Ming; Wynn, Thomas A.; Brombacher, Frank; Brutkiewicz, Randy R.; Kaplan, Mark H.

    2013-01-01

    Efferocytosis of apoptotic neutrophils by macrophages following tissue injury is fundamental to the resolution of inflammation and initiation of tissue repair. Using a sterile peritonitis model in mice, we identified interleukin (IL)-4–producing efferocytosing macrophages in the peritoneum that activate invariant natural killer T (iNKT) cells to produce cytokines including IL-4, IL-13, and interferon-γ. Importantly, IL-4 from macrophages contributes to alternative activation of peritoneal exudate macrophages and augments type 2 cytokine production from NKT cells to suppress inflammation. The increased peritonitis in mice deficient in IL-4, NKT cells, or IL-4Rα expression on myeloid cells suggested that each is a key component for resolution of sterile inflammation. The reduced NAD phosphate oxidase is also critical for this model, because in mice with X-linked chronic granulomatous disease (X-CGD) that lack oxidase subunits, activation of iNKT cells by X-CGD peritoneal exudate macrophages was impaired during sterile peritonitis, resulting in enhanced and prolonged inflammation in these mice. Therefore, efferocytosis-induced IL-4 production and activation of IL-4–producing iNKT cells by macrophages are immunomodulatory events in an innate immune circuit required to resolve sterile inflammation and promote tissue repair. PMID:23426944

  6. Novel immunostimulators with a thiazolidin-4-one ring promote the immunostimulatory effect of human iNKT cells on the stimulation of Th2-like immune responsiveness via GATA3 activation in vitro.

    PubMed

    Meng, Ming; Li, Chunxiao; Yang, Fei; Chen, Hua; Li, Xiaoliu; Yang, Yongbin; Chen, Dongzhi

    2016-10-01

    Invariant natural killer T cells (iNKTs) are important innate immune cells which get involved in various immune responses in both mice and humans. These immune reactions range from self-tolerance to development of autoimmunity and responses to pathogens and tumor development. In this study, we aimed to explore the effects of the novel immunostimulators (CH1b and CH2b) containing thiazolidin-4-one on the functions of human invariant natural killer T cells (iNKTs). First of all, iNKTs in peripheral blood mononuclear cells were expanded with α-Galactosylceramide (α-Galcer) in vitro. Then, the highly purified iNKTs were isolated from PBMCs using magnetic cells sorting (MACS). Next, we investigated the impacts of CH1b and CH2b on proliferation, cytokines production, cytotoxicity, and the associated signaling pathways in iNKT cells. Finally, we found that CH2b could significantly promote the activated iNKTs proliferation, increase the production of Th2 cytokines, and induce Th0 differentiation into Th2 subset via GATA 3 signaling pathway. Besides, CH2b could markedly enhance the cytotoxic ability of the activated iNKTs. Therefore, we concluded that CH2b, a promising candidate immunostimulator, might be used for the treatment of infections, tumors, autoimmune and allergic diseases, and for the correction of Th1/Th2 balance disorders in future. PMID:27543853

  7. Multiple layers of transcriptional regulation by PLZF in NKT-cell development.

    PubMed

    Mao, Ai-Ping; Constantinides, Michael G; Mathew, Rebecca; Zuo, Zhixiang; Chen, Xiaoting; Weirauch, Matthew T; Bendelac, Albert

    2016-07-01

    The transcription factor PLZF [promyelocytic leukemia zinc finger, encoded by zinc finger BTB domain containing 16 (Zbtb16)] is induced during the development of innate and innate-like lymphocytes to direct their acquisition of a T-helper effector program, but the molecular mechanisms involved are poorly understood. Using biotinylation-based ChIP-seq and microarray analysis of both natural killer T (NKT) cells and PLZF-transgenic thymocytes, we identified several layers of regulation of the innate-like NKT effector program. First, PLZF bound and regulated genes encoding cytokine receptors as well as homing and adhesion receptors; second, PLZF bound and activated T-helper-specific transcription factor genes that in turn control T-helper-specific programs; finally, PLZF bound and suppressed the transcription of Bach2, a potent general repressor of effector differentiation in naive T cells. These findings reveal the multilayered architecture of the transcriptional program recruited by PLZF and elucidate how a single transcription factor can drive the developmental acquisition of a broad effector program. PMID:27325774

  8. Extrinsic allospecific signals of hematopoietic origin dictate iNKT cell lineage-fate decisions during development

    PubMed Central

    Strong, Beverly S. I.; Newkold, Tess J.; Lee, Amanda E.; Turner, Lucas E.; Alhajjat, Amir M.; Heusel, Jonathan W.; Shaaban, Aimen F.

    2016-01-01

    Invariant NKT (iNKT) cells are critical to the maintenance of tolerance toward alloantigens encountered during postnatal life pointing to the existence of a process for self-education. However, the impact of developmentally encountered alloantigens in shaping the phenotype and function of iNKT cells has not been described. To better understand this process, the current report examined naïve iNKT cells as they matured in an allogeneic environment. Following the prenatal transfer of fetal hematopoietic cells between age-matched allogeneic murine fetuses, cell-extrinsic signals appeared to dictate allospecific patterns of Ly49 receptor expression and lineage diversity in developing iNKT cells. Regulation for this process arose from cells of hematopoietic origin requiring only rare exposure to facilitate broad changes in developing iNKT cells. These findings highlight surprisingly asymmetric allospecific alterations in iNKT cells as they develop and mature in an allogeneic environment and establish a new paradigm for study of the self-education of iNKT cells. PMID:27354027

  9. Th1 or Th2 balance regulated by interaction between dendritic cells and NKT cells.

    PubMed

    Onoé, Kazunori; Yanagawa, Yoshiki; Minami, Keita; Iijima, Norifumi; Iwabuchi, Kazuya

    2007-01-01

    If Th1 or Th2 polarization could be artificially manipulated, effective immune responses would be generated depending on nature of the targets. In this study we attempted to regulate CD40 expressions on dendritic cells (DCs) in order to modify the T cell response. It was found that reducing agents selectively inhibited surface expression of CD40 on DCs. This finding may provide a new strategy of DC-mediated modulation of the Th1/Th2 balance. It was also shown that NKT-produced Th1/Th2 cytokine balance was under control of negative feedback loop through DCs. Th1 cytokine-pretreated DCs mainly induced Th2 cytokine production, whereas Th2 cytokine-pretreated DCs induced Th1 cytokine production by alpha-galactosylceramide-stimulated NKT cells. The negative feedback regulation system could be applicable to therapeutics of various diseases based on immunological disorders. PMID:17917039

  10. NKT cells can help mediate the protective effects of 1,25-dihydroxyvitamin D3 in experimental autoimmune encephalomyelitis in mice.

    PubMed

    Waddell, Amanda; Zhao, Jun; Cantorna, Margherita T

    2015-05-01

    Active vitamin D [1,25-dihydroxyvitamin D3 (1,25D3)] blocks the development of experimental autoimmune diseases. However, the molecular and immunobiological mechanisms underlying 1,25D3's anti-inflammatory properties are not fully understood. We employed a murine model of experimental autoimmune encephalomyelitis (EAE) in order to determine the role of NKT cells in 1,25D3-mediated protection from EAE. Wild-type (WT) mice or mice lacking all NKT cells (CD1d(-/-)) or invariant NKT cells (Jα18(-/-)) were fed control or 1,25D3-supplemented diets. All mice fed with the control diet developed severe EAE. 1,25D3 treatment of WT mice protected them from developing EAE. CD1d(-/-) and Jα18(-/-) mice treated with 1,25D3 were not protected to the same extent as WT mice. Myelin oligodendrocyte glycoprotein-specific IL-17 and IFN-γ production was significantly reduced in 1,25D3 WT mice compared with WT but was not decreased in 1,25D3 CD1d(-/-) mice compared with CD1d(-/-) mice. IL-4(-/-) mice were utilized to determine how IL-4 deficiency affects susceptibility to EAE. IL-4(-/-) mice were not protected from developing EAE by α-galactosylceramide (α-GalCer) or 1,25D3 treatment. Furthermore, 1,25D3 treatment of splenocytes in vitro decreased α-GalCer-induced IL-17 and increased IL-4, IL-5 and IL-10 production. 1,25D3 alters the cytokine profile of invariant NKT cells in vitro. These studies demonstrate that NKT cells are important mediators of 1,25D3-induced protection from EAE in mice and NKT cell-derived IL-4 may be an important factor in providing this protection. PMID:25574039

  11. Mediastinal Single Nodal Relapse of a Nasal Nk/T cell Lymphoma

    PubMed Central

    Rhee, Kyoung Hoon; Hong, Seok Chan; An, Jeong Min; Huh, Jooryung; Sook, Ryu Jin; Lee, Jin Seong

    2007-01-01

    A nasal NK/T cell lymphoma is a very aggressive form of lymphoma. Patterns of relapse after treatment have not been systematically evaluated, and mediastinal nodal relapse at a primary site has never been documented. We describe here a 40-year old man who presented with a nasal obstruction caused by a protruding mass that was identified as a nasal NK/T cell lymphoma. The initial work-up, including chest and abdominopelvic computed tomography (CT) and positron emission tomography (PET), showed no regional or distant metastasis. A CT scan performed following three cycles of chemotherapy with cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP) showed that the mass had nearly disappeared. Radiation therapy undertaken following chemotherapy was given to the primary site. However, PET performed following radiotherapy revealed a single mediastinal lymphadenopathy, with no evidence of residual tumor in the nasal cavity. A biopsy using video-assisted thoracoscopy (VATS) showed the presence of a recurrent NK/T cell lymphoma with an immunophenotype identical to that of the primary nasal lymphoma. An additional three cycles of CHOP chemotherapy were administered, and the patient remains alive, with no evidence of disease 30 months after the initial relapse. These findings indicate that early detection with PET and prompt surgical excision with the use of VATS can lead to successful treatment of a relapsed nasal NK/T cell lymphoma. PMID:17939339

  12. Mediastinal single nodal relapse of a nasal NK/T cell lymphoma.

    PubMed

    Rhee, Kyoung Hoon; Hong, Seok Chan; An, Jeong Min; Huh, Jooryung; Sook, Ryu Jin; Lee, Jin Seong; Suh, Cheolwon

    2007-09-01

    A nasal NK/T cell lymphoma is a very aggressive form of lymphoma. Patterns of relapse after treatment have not been systematically evaluated, and mediastinal nodal relapse at a primary site has never been documented. We describe here a 40-year old man who presented with a nasal obstruction caused by a protruding mass that was identified as a nasal NK/T cell lymphoma. The initial work-up, including chest and abdominopelvic computed tomography (CT) and positron emission tomography (PET), showed no regional or distant metastasis. A CT scan performed following three cycles of chemotherapy with cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP) showed that the mass had nearly disappeared. Radiation therapy undertaken following chemotherapy was given to the primary site. However, PET performed following radiotherapy revealed a single mediastinal lymphadenopathy, with no evidence of residual tumor in the nasal cavity. A biopsy using video-assisted thoracoscopy (VATS) showed the presence of a recurrent NK/T cell lymphoma with an immunophenotype identical to that of the primary nasal lymphoma. An additional three cycles of CHOP chemotherapy were administered, and the patient remains alive, with no evidence of disease 30 months after the initial relapse. These findings indicate that early detection with PET and prompt surgical excision with the use of VATS can lead to successful treatment of a relapsed nasal NK/T cell lymphoma. PMID:17939339

  13. NKT cell adjuvant-based tumor vaccine for treatment of myc oncogene-driven mouse B-cell lymphoma

    PubMed Central

    West, Alison C.; Steegh, Kim; Duret, Helene; Paget, Christophe; Martin, Ben; Matthews, Geoffrey M.; Shortt, Jake; Chesi, Marta; Bergsagel, P. Leif; Bots, Michael; Zuber, Johannes; Lowe, Scott W.; Johnstone, Ricky W.

    2012-01-01

    Immunomodulators are effective in controlling hematologic malignancy by initiating or reactivating host antitumor immunity to otherwise poorly immunogenic and immune suppressive cancers. We aimed to boost antitumor immunity in B-cell lymphoma by developing a tumor cell vaccine incorporating α-galactosylceramide (α-GalCer) that targets the immune adjuvant properties of NKT cells. In the Eμ-myc transgenic mouse model, single therapeutic vaccination of irradiated, α-GalCer–loaded autologous tumor cells was sufficient to significantly inhibit growth of established tumors and prolong survival. Vaccine-induced antilymphoma immunity required NKT cells, NK cells, and CD8 T cells, and early IL-12–dependent production of IFN-γ. CD4 T cells, gamma/delta T cells, and IL-18 were not critical. Vaccine treatment induced a large systemic spike of IFN-γ and transient peripheral expansion of both NKT cells and NK cells, the major sources of IFN-γ. Furthermore, this vaccine approach was assessed in several other hematopoietic tumor models and was also therapeutically effective against AML-ETO9a acute myeloid leukemia. Replacing α-GalCer with β-mannosylceramide resulted in prolonged protection against Eμ-myc lymphoma. Overall, our results demonstrate a potent immune adjuvant effect of NKT cell ligands in therapeutic anticancer vaccination against oncogene-driven lymphomas, and this work supports clinical investigation of NKT cell–based immunotherapy in patients with hematologic malignancies. PMID:22932803

  14. Zbtb7b (Th-POK) regulates the development of IL-17 producing CD1d-restricted mouse NKT-cells

    PubMed Central

    Enders, Anselm; Stankovic, Sanda; Teh, Charis; Uldrich, Adam P.; Yabas, Mehmet; Juelich, Torsten; Altin, John A.; Frankenreiter, Sandra; Bergmann, Hannes; Roots, Carla M.; Kyparissoudis, Konstantinos; Goodnow, Chris C.; Godfrey, Dale I.

    2012-01-01

    CD1d-dependent NKT-cells represent a heterogeneous family of effector T-cells including CD4+CD8− and CD4−CD8− subsets, that respond to glycolipid antigens with rapid and potent cytokine production. NKT-cell development is regulated by a unique combination of factors, however very little is known about factors that control the development of NKT subsets. Here, we analyze a novel mouse strain (helpless) with a mis-sense mutation in the BTB-POZ domain of Zbtb7b and demonstrate that this mutation has dramatic, intrinsic effects on development of NKT-cell subsets. Although NKT-cell numbers are similar in Zbtb7b mutant mice, these cells are hyperproliferative and most lack CD4 and instead express CD8. Moreover, the majority of Zbtb7b mutant NKT-cells in the thymus are RORγt+ and a high frequency produce IL-17 while very few produce IFN-γ or other cytokines, sharply contrasting the profile of normal NKT-cells. Mice heterozygous for the helpless mutation also have reduced numbers of CD4+ NKT-cells and increased production of IL-17 without an increase in CD8+ cells, suggesting that Zbtb7b acts at multiple stages of NKT-cell development. These results reveal Zbtb7b as a critical factor genetically pre-determining the balance of effector subsets within the NKT-cell population. PMID:23105140

  15. The Role of Hepatic Invariant (I)NKT Cells in Systemic/Local Inflammation and Mortality During Polymicrobial Septic Shock1

    PubMed Central

    Hu, Caroline K.; Venet, Fabienne; Heffernan, David S.; Wang, Yvonne L.; Horner, Brian; Huang, Xin; Chung, Chun-Shiang; Gregory, Stephen H.; Ayala, Alfred

    2009-01-01

    Natural killer T (NKT)4 cells have been described as “innate regulatory cells” because of their rapid response to conserved glycolipids presented on CD1d via their invariant TCR. However, little is known about the contribution of the hepatic NKT cell to the development of a local and/or systemic immune response to acute septic challenge (cecal ligation & puncture; CLP). We found not only that mice deficient in invariant [i] NKT cells (Jα18 -/-) had a marked attenuation in CLP induced mortality, but also exhibited an oblation of the systemic inflammatory response (with little effect on splenic/ peritoneal immune responsiveness). Flow cytometric data indicated that following CLP, there was a marked decline in the % of CD3+αGalCer-CD1d-tetramer+ cells in the mouse C57BL/6J and Balb/c liver non-parenchymal cell population. This was associated with the marked activation of these cells (increased expression of CD69 and CD25) as well as a rise in the frequency of NKT cells positive for both Th1 and Th2 intracellular cytokines. In this respect, when mice were pre-treated in vivo with anti-CD1d blocking antibody we observed not only that this inhibited the systemic rise of IL-6 and IL-10 levels in septic mice and improved overall septic survival, but that the CLP induced changes in liver macrophage IL-6 and IL-10 expressions were inversely effected by this treatment. Together, these findings suggest that the activation of hepatic iNKT cells plays a critical role in regulating the innate immune/ systemic inflammatory response and survival in a model of acute septic shock. PMID:19201902

  16. iNKT Cells Are Responsible for the Apoptotic Reduction of Basophils That Mediate Th2 Immune Responses Elicited by Papain in Mice Following γPGA Stimulation

    PubMed Central

    Park, Se-Ho; Hong, Seokmann

    2016-01-01

    Recent studies have demonstrated that Bacillus subtilis-derived poly-gamma glutamic acid (γPGA) treatment suppresses the development of allergic diseases such as atopic dermatitis (AD). Although basophils, an innate immune cell, are known to play critical roles in allergic immune responses and repeated long-term administration of γPGA results in decreased splenic basophils in an AD murine model, the underlying mechanisms by which γPGA regulates basophil frequency remain unclear. To investigate how γPGA modulates basophils, we employed basophil-mediated Th2 induction in vivo model elicited by the allergen papain protease. Repeated injection of γPGA reduced the abundance of basophils and their production of IL4 in mice, consistent with our previous study using NC/Nga AD model mice. The depletion of basophils by a single injection of γPGA was dependent on the TLR4/DC/IL12 axis. CD1d-dependent Vα14 TCR invariant natural killer T (iNKT) cells are known to regulate a variety of immune responses, such as allergy. Because iNKT cell activation is highly sensitive to IL12 produced by DCs, we evaluated whether the effect of γPGA on basophils is mediated by iNKT cell activation. We found that in vivo γPGA treatment did not induce the reduction of basophils in iNKT cell-deficient CD1d KO mice, suggesting the critical role of iNKT cells in γPGA-mediated basophil depletion at the early time points. Furthermore, increased apoptotic basophil reduction triggered by iNKT cells upon γPGA stimulation was mainly attributed to Th1 cytokines such as IFNγ and TNFα, consequently resulting in inhibition of papain-induced Th2 differentiation via diminishing basophil-derived IL4. Taken together, our results clearly demonstrate that γPGA-induced iNKT cell polarization toward the Th1 phenotype induces apoptotic basophil depletion, leading to the suppression of Th2 immune responses. Thus, elucidation of the crosstalk between innate immune cells will contribute to the design and

  17. iNKT Cells Are Responsible for the Apoptotic Reduction of Basophils That Mediate Th2 Immune Responses Elicited by Papain in Mice Following γPGA Stimulation.

    PubMed

    Park, Hyun Jung; Lee, Sung Won; Park, Se-Ho; Hong, Seokmann

    2016-01-01

    Recent studies have demonstrated that Bacillus subtilis-derived poly-gamma glutamic acid (γPGA) treatment suppresses the development of allergic diseases such as atopic dermatitis (AD). Although basophils, an innate immune cell, are known to play critical roles in allergic immune responses and repeated long-term administration of γPGA results in decreased splenic basophils in an AD murine model, the underlying mechanisms by which γPGA regulates basophil frequency remain unclear. To investigate how γPGA modulates basophils, we employed basophil-mediated Th2 induction in vivo model elicited by the allergen papain protease. Repeated injection of γPGA reduced the abundance of basophils and their production of IL4 in mice, consistent with our previous study using NC/Nga AD model mice. The depletion of basophils by a single injection of γPGA was dependent on the TLR4/DC/IL12 axis. CD1d-dependent Vα14 TCR invariant natural killer T (iNKT) cells are known to regulate a variety of immune responses, such as allergy. Because iNKT cell activation is highly sensitive to IL12 produced by DCs, we evaluated whether the effect of γPGA on basophils is mediated by iNKT cell activation. We found that in vivo γPGA treatment did not induce the reduction of basophils in iNKT cell-deficient CD1d KO mice, suggesting the critical role of iNKT cells in γPGA-mediated basophil depletion at the early time points. Furthermore, increased apoptotic basophil reduction triggered by iNKT cells upon γPGA stimulation was mainly attributed to Th1 cytokines such as IFNγ and TNFα, consequently resulting in inhibition of papain-induced Th2 differentiation via diminishing basophil-derived IL4. Taken together, our results clearly demonstrate that γPGA-induced iNKT cell polarization toward the Th1 phenotype induces apoptotic basophil depletion, leading to the suppression of Th2 immune responses. Thus, elucidation of the crosstalk between innate immune cells will contribute to the design and

  18. Adjuvant effects of invariant NKT cell ligand potentiates the innate and adaptive immunity to an inactivated H1N1 swine influenza virus vaccine in pigs.

    PubMed

    Dwivedi, Varun; Manickam, Cordelia; Dhakal, Santosh; Binjawadagi, Basavaraj; Ouyang, Kang; Hiremath, Jagadish; Khatri, Mahesh; Hague, Jacquelyn Gervay; Lee, Chang Won; Renukaradhya, Gourapura J

    2016-04-15

    Pigs are considered as the source of some of the emerging human flu viruses. Inactivated swine influenza virus (SwIV) vaccine has been in use in the US swine herds, but it failed to control the flu outbreaks. The main reason has been attributed to lack of induction of strong local mucosal immunity in the respiratory tract. Invariant natural killer T (iNKT) cell is a unique T cell subset, and activation of iNKT cell using its ligand α-Galactosylceramide (α-GalCer) has been shown to potentiate the cross-protective immunity to inactivated influenza virus vaccine candidates in mice. Recently, we discovered iNKT cell in pig and demonstrated its activation using α-GalCer. In this study, we evaluated the efficacy of an inactivated H1N1 SwIV coadministered with α-GalCer intranasally against a homologous viral challenge. Our results demonstrated the potent adjuvant effects of α-GalCer in potentiating both innate and adaptive immune responses to SwIV Ags in the lungs of pigs, which resulted in reduction in the lung viral load by 3 logs compared to without adjuvant. Immunologically, in the lungs of pigs vaccinated with α-GalCer an increased virus specific IgA response, IFN-α secretion and NK cell-cytotoxicity was observed. In addition, iNKT cell-stimulation enhanced the secretion of Th1 cytokines (IFN-γ and IL-12) and reduced the production of immunosuppressive cytokines (IL-10 and TGF-β) in the lungs of pigs⋅ In conclusion, we demonstrated for the first time iNKT cell adjuvant effects in pigs to SwIV Ags through augmenting the innate and adaptive immune responses in the respiratory tract. PMID:27016770

  19. Primary Esophageal Extranasal NK/T Cell Lymphoma With Biphasic Morphology

    PubMed Central

    Ye, Zi-Yin; Cao, Qing-Hua; Liu, Fang; Lu, Xiao-Fang; Li, Shu-Rong; Li, Chang-Zhao; Chen, Shao-Hong

    2015-01-01

    Abstract We report a case of esophageal extranasal NK/T cell lymphoma with biphasic morphologic features revealed by a deep large piecemeal biopsy. A 40-year-old man present with pharyngalgia, dysphagia, recurrent fever, and 5-kg weight loss for 8 months. Endoscopy demonstrated progressing longitudinal ulcers and mucosal bridges along the esophagus. The first and second biopsies obtained superficial mucosa with scattered bland-looking small lymphocytes. A subsequent large piecemeal snare abscission for biopsy showed atypical lymphoid cells infiltrating into the deep lamina propria and muscularis mucosae, whereas the superficial lamina propria was highly edematous with scant small lymphocytes. Immunohistochemical studies confirmed that both underlying atypical cells and superficial small lymphocytes were neoplastic, sharing an identical immunophenotype: positive for CD2, CD3, CD43, CD8, CD56, TIA-1 and granzyme B. Epstein-Barr virus–encoded small RNAs were found in both cells. The histologic findings were diagnostic of primary esophageal extranasal NK/T cell lymphoma. However, the patient developed bone marrow depression during chemotherapy and died of massive cerebral hemorrhage after the first cycle of chemotherapy. Primary esophageal extranodal NK/T cell lymphoma nasal type is extremely rare. We show the biphasic morphology of this disease, which highlights the importance of deep biopsy for accurate diagnosis. PMID:26181557

  20. Ly108 Expression Distinguishes Subsets of invariant NKT cells that Help Autoantibody Production and Secrete IL-21 from those that Secrete IL-17 in Lupus Prone NZB/W Mice

    PubMed Central

    Tang, Xiaobin; Zhang, Bo; Jarrell, Justin A; Price, Jordan V; Dai, Hongjie; Utz, Paul J; Strober, Samuel

    2014-01-01

    Lupus is a systemic autoimmune disease characterized by anti-nuclear antibodies in humans and genetically susceptible NZB/W mice that can cause immune complex glomerulonephritis. T cells contribute to lupus pathogenesis by secreting pro-inflammatory cytokines such as IL-17, and by interacting with B cells and secreting helper factors such as IL-21 that promote production of IgG autoantibodies. In the current study, we determined whether purified NKT cells or far more numerous conventional non-NKT cells in the spleen of NZB/W female mice secrete IL-17 and/or IL-21 after TCR activation in vitro, and provide help for spontaneous IgG autoantibody production by purified splenic CD19+ B cells. Whereas invariant NKT cells secreted large amounts of IL-17 and IL-21, and helped B cells, non-NKT cells did not. The subset of IL-17 secreting NZB/W NKT cells expressed the Ly108loCD4−NK1.1− phenotype, whereas the IL-21 secreting subset expressed the Ly108hiCD4+NK1.1− phenotype and helped B cells secrete a variety of IgG anti-nuclear antibodies. α-galactocylceramide enhanced the helper activity of NZB/W and B6.Sle1b NKT cells for IgG autoantibodiy secretion by syngeneic B cells. In conclusion, different subsets of iNKT cells from mice with genetic susceptibility to lupus can contribute to pathogenesis by secreting pro-inflammatory cytokines and helping autoantibody production. PMID:24508410

  1. Antigen-specific human NKT cells from tuberculosis patients produce IL-21 to help B cells for the production of immunoglobulins

    PubMed Central

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

    2015-01-01

    Natural killer T (NKT) cells from mouse and human play an important role in the immune responses against Mycobacterium tuberculosis. However, the function of CD3+TCRvβ11+ NKT cells at the local site of M. tuberculosis infection remains poorly defined. In the present study, we found that after stimulation with M. tuberculosis antigens, NKT cells isolated from tuberculosis (TB) pleural fluid mononuclear cells (PFMCs) produced IL-21 and other cytokines including IFN-γ, TNF-α, IL-2 and IL-17. IL-21-expressing NKT cells in PFMCs displayed effector memory phenotype, expressing CD45ROhighCD62LlowCCR7low. Moreover, NKT cells expressed high levels of CXCR5 and all of IL-21-expressing NKT cells co-expressed CXCR5. The frequency of BCL-6-expression was higher in IL-21-expressing but not in non-IL-21-expressing CD3+TCRvβ11+ NKT cells. Sorted CD3+TCRvβ11+ NKT cells from PFMCs produced IFN-γ and IL-21 after stimulation, which expressed CD40L. Importantly, CD3+TCRvβ11+ NKT cells provided help to B cells for the production of IgG and IgA. Taken together, our data demonstrate that CD3+TCRvβ11+ NKT cells from a local site of M. tuberculosis infection produce IL-21, express CXCR5 and CD40L, help B cells to secrete IgG and IgA, and may participate in local immune responses against M. tuberculosis infection. PMID:26416419

  2. Increased Intraepithelial Vα24 Invariant NKT Cells in the Celiac Duodenum

    PubMed Central

    Montalvillo, Enrique; Bernardo, David; Martínez-Abad, Beatriz; Allegretti, Yessica; Fernández-Salazar, Luis; Calvo, Carmen; Chirdo, Fernando G.; Garrote, José A.; Arranz, Eduardo

    2015-01-01

    Celiac Disease (CD) is an interferon (IFN)γ-mediated duodenal hypersensitivity to wheat gluten occurring in genetically predisposed individuals. Gluten-free diet (GFD) leads to a complete remission of the disease. Vα24-restricted invariant NKT (iNKT) cells are important to maintain immune homeostasis in the gut mucosa because of their unique capacity to rapidly produce large quantities of both T-helper (Th)1 and Th2 cytokines upon stimulation. We studied the presence of these cells in the CD duodenum. Duodenal biopsies were obtained from 45 untreated-CD patients (uCD), 15 Gluten Free Diet-CD patients (GFD-CD), 44 non-inflamed non-CD controls (C-controls) and 15 inflamed non-CD controls (I-controls). Two populations from Spain and Argentina were recruited. Messenger RNA (mRNA) expression of Vα24-Jα18 (invariant TCRα chain of human iNKT cells), IFNγ and intracellular transcription factor Forkhead Box P3 (Foxp3), and flow cytometry intraepithelial lymphocyte (IEL) profile were determined. Both uCD and GFD-CD patients had higher Vα24-Jα18 mRNA levels than non-CD controls (I and C-controls). The expression of Vα24-Jα18 correlated with Marsh score for the severity of mucosal lesion and also with increased mRNA IFNγ levels. uCD and GFD-CD patients had decreased mRNA expression of FoxP3 but increased expression of Vα24-Jα18, which revealed a CD-like molecular profile. Increased numbers of iNKT cells were confirmed by flow cytometry within the intraepithelial lymphocyte compartment of uCD and GFD-CD patients and correlated with Vα24-Jα18 mRNA expression. In conclusion, we have found an increased number of iNKT cells in the duodenum from both uCD and GFD-CD patients, irrespective of the mucosal status. A CD-like molecular profile, defined by an increased mRNA expression of Vα24-Jα18 together with a decreased expression of FoxP3, may represent a pro-inflammatory signature of the CD duodenum. PMID:26529008

  3. Lineage-Specific Effector Signatures of Invariant NKT Cells Are Shared amongst γδ T, Innate Lymphoid, and Th Cells.

    PubMed

    Lee, You Jeong; Starrett, Gabriel J; Lee, Seungeun Thera; Yang, Rendong; Henzler, Christine M; Jameson, Stephen C; Hogquist, Kristin A

    2016-08-15

    Invariant NKT cells differentiate into three predominant effector lineages in the steady state. To understand these lineages, we sorted undifferentiated invariant NK T progenitor cells and each effector population and analyzed their transcriptional profiles by RNAseq. Bioinformatic comparisons were made to effector subsets among other lymphocytes, specifically Th cells, innate lymphoid cells (ILC), and γδ T cells. Myc-associated signature genes were enriched in NKT progenitors, like in other hematopoietic progenitors. Only NKT1 cells, but not NKT2 and NKT17 cells, had transcriptome similarity to NK cells and were also similar to other IFN-γ-producing lineages such as Th1, ILC1, and intraepithelial γδ T cells. NKT2 and NKT17 cells were similar to their analogous subsets of γδ T cells and ILCs, but surprisingly, not to Th2 and Th17 cells. We identified a set of genes common to each effector lineage regardless of Ag receptor specificity, suggesting the use of conserved regulatory cores for effector function. PMID:27385777

  4. MicroRNA-181a/b-1 Is Not Required for Innate γδ NKT Effector Cell Development.

    PubMed

    Sandrock, Inga; Ziętara, Natalia; Łyszkiewicz, Marcin; Oberdörfer, Linda; Witzlau, Katrin; Krueger, Andreas; Prinz, Immo

    2015-01-01

    Thymic development of αβ T lymphocytes into invariant natural killer (NK) T cells depends on their selection via agonistic lipid antigen presented by CD1d. If successful, newly selected NKT cells gain effector functions already in the thymus. Some γδ T cell subsets also acquire effector functions in the thymus. However, it is not clear whether agonistic TCR stimulation is involved in thymic γδ T cell selection and development. Here we combine two genetic models to address this question. MiR-181a/b-1-/-mice, which show impaired agonistic T cell selection of invariant αβ NKT cells, were crossed to Tcrd-H2BeGFP reporter mice to monitor selection, intra-thymic expansion and differentiation of γδ T cells. We found that miR-181a/b-1-deficiency had no effect on numbers of thymic γδ T cell or on their differentiation towards an IL-17- or IFN-γ-producing effector phenotype. Also, the composition of peripheral lymph node γδ T cells was not affected by miR-181a/b-1-deficiency. Dendritic epidermal γδ T cells were normally present in knock-out animals. However, we observed elevated frequencies and numbers of γδ NKT cells in the liver, possibly because γδ NKT cells can expand and replace missing αβ NKT cells in peripheral niches. In summary, we investigated the role of miR-181a/b-1 for selection, intrathymic development and homeostasis of γδ T cells. We conclude that miR-181a/b-1-dependent modulation of T cell selection is not critically required for innate development of γδ NKT cells or of any other γδ T cell subtypes. PMID:26673421

  5. MicroRNA-181a/b-1 Is Not Required for Innate γδ NKT Effector Cell Development

    PubMed Central

    Sandrock, Inga; Ziętara, Natalia; Łyszkiewicz, Marcin; Oberdörfer, Linda; Witzlau, Katrin; Krueger, Andreas; Prinz, Immo

    2015-01-01

    Thymic development of αβ T lymphocytes into invariant natural killer (NK) T cells depends on their selection via agonistic lipid antigen presented by CD1d. If successful, newly selected NKT cells gain effector functions already in the thymus. Some γδ T cell subsets also acquire effector functions in the thymus. However, it is not clear whether agonistic TCR stimulation is involved in thymic γδ T cell selection and development. Here we combine two genetic models to address this question. MiR-181a/b-1–/–mice, which show impaired agonistic T cell selection of invariant αβ NKT cells, were crossed to Tcrd-H2BeGFP reporter mice to monitor selection, intra-thymic expansion and differentiation of γδ T cells. We found that miR-181a/b-1-deficiency had no effect on numbers of thymic γδ T cell or on their differentiation towards an IL-17- or IFN-γ-producing effector phenotype. Also, the composition of peripheral lymph node γδ T cells was not affected by miR-181a/b-1-deficiency. Dendritic epidermal γδ T cells were normally present in knock-out animals. However, we observed elevated frequencies and numbers of γδ NKT cells in the liver, possibly because γδ NKT cells can expand and replace missing αβ NKT cells in peripheral niches. In summary, we investigated the role of miR-181a/b-1 for selection, intrathymic development and homeostasis of γδ T cells. We conclude that miR-181a/b-1-dependent modulation of T cell selection is not critically required for innate development of γδ NKT cells or of any other γδ T cell subtypes. PMID:26673421

  6. CD155/CD226-interaction impacts on the generation of innate CD8(+) thymocytes by regulating iNKT-cell differentiation.

    PubMed

    Georgiev, Hristo; Ravens, Inga; Shibuya, Akira; Förster, Reinhold; Bernhardt, Günter

    2016-04-01

    The cell surface receptor CD155 influences a variety of immune processes by binding to its ligands CD226, CD96, or TIGIT. Here, we report that the interaction of CD155 with CD226 in the thymus of BALB/c mice has a dual function. It directly influences the dwell time of memory-like CD8(+) T cells, while it is indirectly involved in generating these cells. It was shown earlier that a massive emergence of memory-like CD8 T cells in thymus crucially depends on abundant IL-4, secreted in steady state by iNKT2 (where iNKT is invariant NKT) cells, a subclass of iNKT cells. Here, we show that absence of either CD155 or CD226 in BALB/c mice causes a profound shift in the iNKT subtype composition in thymus, expanding the frequency and numbers of iNKT1 cells at the expense of iNKT2 cells, as well as iNKT17 cells. This shift results in a drop of available IL-4 and creates a scenario similar to that observed in C57BL/6 mice, where iNKT1 cells predominate and iNKT2 cells are much less frequent when compared with BALB/c mice. Yet also in C57BL/6 mice, lack of CD155 or CD226 provokes a further decline in iNKT2 cells, suggesting that the observed effects are not restricted to a particular inbred strain. PMID:26689152

  7. IL-13Rα2-Bearing, Type II NKT Cells Reactive to Sulfatide Self-Antigen Populate the Mucosa of Ulcerative Colitis

    PubMed Central

    Fuss, Ivan J.; Joshi, Bharat; Yang, Zhiqiong; Degheidy, Heba; Fichtner-Feigl, Stefan; de Souza, Heitor; Rieder, Florian; Scaldaferri, Franco; Schirbel, Anja; Scarpa, Melania; West, Gail; Yi, Chuli; Xu, Lili; Leland, Pamela; Yao, Michael; Mannon, Peter; Puri, Raj K.; Fiocchi, Claudio; Strober, Warren

    2016-01-01

    Objective Previous studies have shown that ulcerative colitis (UC) is associated with the presence of lamina propria non-invariant (Type II) NKT cells producing IL-13 and mediating epithelial cell cytotoxicity. Here we sought to define the antigen(s) stimulating the NKT cells and to quantitate these cells in the UC lamina propria. Design Detection of Type II NKT cells in UC lamina propria mononuclear cells (LPMCs) with lysosulfatide loaded tetramer and quantum dot-based flow cytometry and staining. Culture of UC LPMCs with lyso-sulfatide glycolipid to determine sulfatide induction of epithelial cell cytotoxicity, IL-13 production and IL-13Rα2 expression. Blinded quantum dot-based phenotypic analysis to assess UC LPMC expression of IL-13Rα2, CD161 and IL-13. Results Approximately 36% of UC LPMC were lyso-sulfatide tetramer positive whereas few if any control LPMC were positive. When tested, the positive cells were also CD3 and IL-13Rα2 positive. Culture of UC LPMC with lyso-sulfatide glycolipid showed that sulfatide stimulates UC LPMC production of IL-13 and induces UC CD161+ LPMC-mediated cytotoxicity of activated epithelial cells; in addition, lyso-sulfatide induces enhanced expression of IL-13Rα2. Finally, blinded phenotypic analysis of UC LP MC using multi-color quantum dot staining technology showed that approximately 60% of the LPMC bear both IL-13Rα2 and CD161 and most of these cells also produce IL-13. Conclusion These studies show that UC lamina propria is replete with Type II NKT cells responsive to lyso-sulfatide glycolipid and bearing IL-13Rα2. Since lyso-sulfatide is a self-antigen these data suggest that an autoimmune response is involved in UC pathogenesis. PMID:24515806

  8. Altered Development of NKT Cells, γδ T Cells, CD8 T Cells and NK Cells in a PLZF Deficient Patient

    PubMed Central

    Beaulieu, Aimee M.; Zaidi, Bushra; Carsons, Steven E.; Crow, Peggy K.; Yuan, Jianda; Wolchok, Jedd D.; Horsthemke, Bernhard; Wieczorek, Dagmar; Sant'Angelo, Derek B.

    2011-01-01

    In mice, the transcription factor, PLZF, controls the development of effector functions in invariant NKT cells and a subset of NKT cell-like, γδ T cells. Here, we show that in human lymphocytes, in addition to invariant NKT cells, PLZF was also expressed in a large percentage of CD8+ and CD4+ T cells. Furthermore, PLZF was also found to be expressed in all γδ T cells and in all NK cells. Importantly, we show that in a donor lacking functional PLZF, all of these various lymphocyte populations were altered. Therefore, in contrast to mice, PLZF appears to control the development and/or function of a wide variety of human lymphocytes that represent more than 10% of the total PBMCs. Interestingly, the PLZF-expressing CD8+ T cell population was found to be expanded in the peripheral blood of patients with metastatic melanoma but was greatly diminished in patients with autoimmune disease. PMID:21915328

  9. Organ-Specific Protective Role of NKT Cells in Virus-Induced Inflammatory Demyelination and Myocarditis Depends on Mouse Strain

    PubMed Central

    Kawai, Eiichiro; Sato, Fumitaka; Omura, Seiichi; Martinez, Nicholas E.; Reddy, Pratap C.; Taniguchi, Masaru; Tsunoda, Ikuo

    2014-01-01

    Theiler’s murine encephalomyelitis virus (TMEV) can induce demyelination or myocarditis in susceptible mouse strains. A deficiency of NKT cells exacerbated TMEV-induced demyelinating disease (TMEV-IDD) in SJL/J and BALB/c mice. In C57BL/6 background, however, NKT-cell-deficient Jαt 18 KO mice remained as resistant to TMEV-IDD as wild-type mice. Echocardiography and histology showed that Jα18 KO mice developed more severe myocarditis (greater T cell infiltration and fibrosis) than wild-type mice, suggesting a protective role of NKT cells in myocarditis in C57BL/6 mice. Jα18 KO mice had higher cardiac viral RNA and anti-viral antibody titers, but had lower lymphoproliferation and IL-4 and IL-10 production. PMID:25434008

  10. The Prognostic Impact of NK/NKT Cell Density in Periampullary Adenocarcinoma Differs by Morphological Type and Adjuvant Treatment

    PubMed Central

    Warfvinge, Carl Fredrik; Elebro, Jacob; Heby, Margareta; Nodin, Björn; Krzyzanowska, Agnieszka; Bjartell, Anders; Leandersson, Karin; Eberhard, Jakob; Jirström, Karin

    2016-01-01

    Background Natural killer (NK) cells and NK T cells (NKT) are vital parts of tumour immunosurveillance. However, their impact on prognosis and chemotherapy response in periampullary adenocarcinoma, including pancreatic cancer, has not yet been described. Methods Immune cell-specific expression of CD56, CD3, CD68 and CD1a was analysed by immunohistochemistry on tissue microarrays with tumours from 175 consecutive cases of periampullary adenocarcinoma, 110 of pancreatobiliary type (PB-type) and 65 of intestinal type (I-type) morphology. Kaplan-Meier and Cox regression analysis were applied to determine the impact of CD56+ NK/NKT cells on 5-year overall survival (OS). Results High density of CD56+ NK/NKT cells correlated with low N-stage and lack of perineural, lymphatic vessel and peripancreatic fat invasion. High density of CD56+ NK/NKT cells was associated with prolonged OS in Kaplan-Meier analysis (p = 0.003), and in adjusted Cox regression analysis (HR = 0.49; 95% CI 0.29–0.86). The prognostic effect of high CD56+ NK/NKT cell infiltration was only evident in cases not receiving adjuvant chemotherapy in PB-type tumours (p for interaction = 0.014). Conclusion This study demonstrates that abundant infiltration of CD56+ NK/NKT cells is associated with a prolonged survival in periampullary adenocarcinoma. However, the negative interaction with adjuvant treatment is noteworthy. NK cell enhancing strategies may prove to be successful in the management of these cancers. PMID:27275582

  11. Structural and Functional Changes of the Invariant NKT Clonal Repertoire in Early Rheumatoid Arthritis.

    PubMed

    Mansour, Salah; Tocheva, Anna S; Sanderson, Joseph P; Goulston, Lyndsey M; Platten, Helen; Serhal, Lina; Parsons, Camille; Edwards, Mark H; Woelk, Christopher H; Elkington, Paul T; Elliott, Tim; Cooper, Cyrus; Edwards, Christopher J; Gadola, Stephan D

    2015-12-15

    Invariant NKT cells (iNKT) are potent immunoregulatory T cells that recognize CD1d via a semi-invariant TCR (iNKT-TCR). Despite the knowledge of a defective iNKT pool in several autoimmune conditions, including rheumatoid arthritis (RA), a clear understanding of the intrinsic mechanisms, including qualitative and structural changes of the human iNKT repertoire at the earlier stages of autoimmune disease, is lacking. In this study, we compared the structure and function of the iNKT repertoire in early RA patients with age- and gender-matched controls. We analyzed the phenotype and function of the ex vivo iNKT repertoire as well as CD1d Ag presentation, combined with analyses of a large panel of ex vivo sorted iNKT clones. We show that circulating iNKTs were reduced in early RA, and their frequency was inversely correlated to disease activity score 28. Proliferative iNKT responses were defective in early RA, independent of CD1d function. Functional iNKT alterations were associated with a skewed iNKT-TCR repertoire with a selective reduction of high-affinity iNKT clones in early RA. Furthermore, high-affinity iNKTs in early RA exhibited an altered functional Th profile with Th1- or Th2-like phenotype, in treatment-naive and treated patients, respectively, compared with Th0-like Th profiles exhibited by high-affinity iNKTs in controls. To our knowledge, this is the first study to provide a mechanism for the intrinsic qualitative defects of the circulating iNKT clonal repertoire in early RA, demonstrating defects of iNKTs bearing high-affinity TCRs. These defects may contribute to immune dysregulation, and our findings could be exploited for future therapeutic intervention. PMID:26553073

  12. Regulatory iNKT cells lack expression of the transcription factor PLZF and control the homeostasis of T(reg) cells and macrophages in adipose tissue.

    PubMed

    Lynch, Lydia; Michelet, Xavier; Zhang, Sai; Brennan, Patrick J; Moseman, Ashley; Lester, Chantel; Besra, Gurdyal; Vomhof-Dekrey, Emilie E; Tighe, Mike; Koay, Hui-Fern; Godfrey, Dale I; Leadbetter, Elizabeth A; Sant'Angelo, Derek B; von Andrian, Ulrich; Brenner, Michael B

    2015-01-01

    Invariant natural killer T cells (iNKT cells) are lipid-sensing innate T cells that are restricted by the antigen-presenting molecule CD1d and express the transcription factor PLZF. iNKT cells accumulate in adipose tissue, where they are anti-inflammatory, but the factors that contribute to their anti-inflammatory nature, as well as their targets in adipose tissue, are unknown. Here we found that iNKT cells in adipose tissue had a unique transcriptional program and produced interleukin 2 (IL-2) and IL-10. Unlike other iNKT cells, they lacked PLZF but expressed the transcription factor E4BP4, which controlled their IL-10 production. The adipose iNKT cells were a tissue-resident population that induced an anti-inflammatory phenotype in macrophages and, through the production of IL-2, controlled the number, proliferation and suppressor function of regulatory T cells (Treg cells) in adipose tissue. Thus, iNKT cells in adipose tissue are unique regulators of immunological homeostasis in this tissue. PMID:25436972

  13. The Role of CD1d-Restricted NKT Cells in the Clearance of Pseudomonas aeruginosa from the Lung Is Dependent on the Host Genetic Background

    PubMed Central

    Benoit, Patrick; Sigounas, Vaia Yioula; Thompson, Jenna L.; van Rooijen, Nico; Poynter, Matthew E.; Wargo, Matthew J.

    2015-01-01

    Pseudomonas aeruginosa is an important human opportunistic pathogen, accounting for a significant fraction of hospital-acquired lung infections. CD1d-restricted NKT cells comprise an unusual innate-like T cell subset that plays important roles in both bacterial and viral infections. Previous reports have differed in their conclusions regarding the role of NKT cells in clearance of P. aeruginosa from the lung. Since there is significant strain-dependent variation in NKT cell number and function among different inbred strains of mice, we investigated whether the role of NKT cells was dependent on the host genetic background. We found that NKT cells did indeed play a critical role in the clearance of P. aeruginosa from the lungs of BALB/c mice but that they played no discernible role in clearance from the lungs of C57BL/6 mice. We found that the strain-dependent role of NKT cells was associated with significant strain-dependent differences in cytokine production by lung NKT cells and that impaired clearance of P. aeruginosa in BALB/c CD1d−/− mice was associated with an increase in neutrophil influx to the lung and increased levels of proinflammatory cytokines and chemokines after infection. Finally, we found that the role of alveolar macrophages was also dependent on the genetic background. These data provide further support for a model in which the unusually high level of variability in NKT cell number and function among different genetic backgrounds may be an important contributor to infectious-disease susceptibility and pathology. PMID:25870224

  14. The CD4 T cell-deficient mouse mutation nackt (nkt) involves a deletion in the cathepsin L (CtsI) gene.

    PubMed

    Benavides, F; Venables, A; Poetschke Klug, H; Glasscock, E; Rudensky, A; Gómez, M; Martin Palenzuela, N; Guénet, J L; Richie, E R; Conti, C J

    2001-04-01

    We recently reported a novel autosomal recessive mouse mutation designated nackt (nkt). Homozygous mutant mice have diffuse alopecia and a marked reduction in the proportion of CD4+ T cells in the thymus and peripheral lymphoid tissues. Here we show that the CD4 T-cell deficiency is due to a defect in the thymic microenvironment rather than the hematopoietic compartment. Furthermore, we identified the molecular basis of the mutant phenotype by demonstrating that the nkt mutation represents a 118-bp deletion of the cathepsin L (Ctsl) gene which is required for degradation of the invariant chain, a critical chaperone for major histocompatibility complex class II molecules. This finding explains the similarities in skin and immune defects observed in nkt/nkt and Ctsl -/- mice. The data reported here provide further in vivo evidence that the lysosomal cysteine protease cathepsin L plays a critical role in CD4+ T-cell selection in the thymus. PMID:11398968

  15. Isthmin 1 Is a Secreted Protein Expressed in Skin, Mucosal Tissues, and NK, NKT, and Th17 Cells

    PubMed Central

    Valle-Rios, Ricardo; Maravillas-Montero, José L.; Burkhardt, Amanda M.; Martinez, Cynthia; Buhren, Bettina Alexandra; Homey, Bernhard; Gerber, Peter Arne; Robinson, Octavio; Hevezi, Peter

    2014-01-01

    Using a comprehensive microarray database of human gene expression, we identified that in mammals, a secreted protein known as isthmin 1 (ISM1) is expressed in skin, mucosal tissues, and selected lymphocyte populations. ISM1 was originally identified in Xenopus brain during development, and it encodes a predicted ∼50-kDa protein containing a signal peptide, a thrombospondin domain, and an adhesion-associated domain. We confirmed the pattern of expression of ISM1 in both human and mouse tissues. ISM1 is expressed by DX5+ lung lymphocytes that include NK and NKT-like cells, and is also expressed by some CD4+ T cells upon activation but its expression increases significantly when CD4+ T cells were polarized to the Th17 lineage in vitro. The presence of IFN-γ during CD4+ T cell polarization inhibits ISM1 expression. Given that ISM1 has been reported to have anti-angiogenic properties, these observations suggest that ISM1 is a mediator of lymphocyte effector functions and may participate in both innate and acquired immune responses. PMID:24956034

  16. Vaccine-Induced Antibody Isotypes Are Skewed by Impaired CD4 T Cell and Invariant NKT Cell Effector Responses in MyD88-Deficient Mice1

    PubMed Central

    Iweala, Onyinye I.; Smith, Donald W.; Matharu, Kabir S.; Sada-Ovalle, Isabel; Nguyen, Deanna D.; DeKruyff, Rosemarie H.; Umetsu, Dale T.; Behar, Samuel M.; Nagler, Cathryn R.

    2015-01-01

    The requirement for TLR signaling in the initiation of an Ag-specific Ab response is controversial. In this report we show that a novel OVA-expressing recombinant Salmonella vaccine (Salmonella-OVA) elicits a Th1-biased cell-mediated and serum Ab response upon oral or i.p. immunization of C57BL/6 mice. In MyD88−/−mice, Th1-dependent Ab responses are greatly reduced while Th2-dependent Ab isotypes are elevated in response to oral and i.p., but not s.c. footpad, immunization. When the T effector response to oral vaccination is examined we find that activated, adoptively transferred Ag-specific CD4+ T cells accumulate in the draining lymph nodes, but fail to produce IFN-γ, in MyD88−/− mice. Moreover, CD1d tetramer staining shows that invariant NKT cells are activated in response to oral Salmonella-OVA vaccination in wild-type, but not MyD88−/−, mice. Treatment with neutralizing Ab to CD1d reduces the OVA-specific Ab response only in MyD88-sufficient wild-type mice, suggesting that both Ag-specific CD4 T cell and invariant NKT cell effector responses to Salmonella-OVA vaccination are MyD88 dependent. Taken together, our data indicate that the type of adaptive immune response generated to this live attenuated vaccine is regulated by both the presence of MyD88-mediated signals and vaccination route, which may have important implications for future vaccine design. PMID:19620295

  17. CRISPR-Mediated Triple Knockout of SLAMF1, SLAMF5 and SLAMF6 Supports Positive Signaling Roles in NKT Cell Development

    PubMed Central

    Huang, Bonnie; Gomez-Rodriguez, Julio; Preite, Silvia; Garrett, Lisa J.; Harper, Ursula L.; Schwartzberg, Pamela L.

    2016-01-01

    The SLAM family receptors contribute to diverse aspects of lymphocyte biology and signal via the small adaptor molecule SAP. Mutations affecting SAP lead to X-linked lymphoproliferative syndrome Type 1, a severe immunodysregulation characterized by fulminant mononucleosis, dysgammaglobulinemia, and lymphoproliferation/lymphomas. Patients and mice having mutations affecting SAP also lack germinal centers due to a defect in T:B cell interactions and are devoid of invariant NKT (iNKT) cells. However, which and how SLAM family members contribute to these phenotypes remains uncertain. Three SLAM family members: SLAMF1, SLAMF5 and SLAMF6, are highly expressed on T follicular helper cells and germinal center B cells. SLAMF1 and SLAMF6 are also implicated in iNKT development. Although individual receptor knockout mice have limited iNKT and germinal center phenotypes compared to SAP knockout mice, the generation of multi-receptor knockout mice has been challenging, due to the genomic linkage of the genes encoding SLAM family members. Here, we used Cas9/CRISPR-based mutagenesis to generate mutations simultaneously in Slamf1, Slamf5 and Slamf6. Genetic disruption of all three receptors in triple-knockout mice (TKO) did not grossly affect conventional T or B cell development and led to mild defects in germinal center formation post-immunization. However, the TKO worsened defects in iNKT cells development seen in SLAMF6 single gene-targeted mice, supporting data on positive signaling and potential redundancy between these receptors. PMID:27258160

  18. IL-15 Superagonist Expands mCD8+ T, NK and NKT Cells after Burn Injury but Fails to Improve Outcome during Burn Wound Infection

    PubMed Central

    Patil, Naeem K.; Luan, Liming; Bohannon, Julia K.; Guo, Yin; Hernandez, Antonio; Fensterheim, Benjamin; Sherwood, Edward R.

    2016-01-01

    Background Severely burned patients are highly susceptible to opportunistic infections and sepsis, owing to the loss of the protective skin barrier and immunological dysfunction. Interleukin-15 (IL-15) belongs to the IL-2 family of common gamma chain cytokines and stimulates the proliferation and activation of T (specifically memory CD8), NK and NKT cells. It has been shown to preserve T cell function and improve survival during cecal ligation and puncture (CLP)-induced sepsis in mice. However, the therapeutic efficacy of IL-15 or IL-15 superagonist (SA) during infection after burn injury has not been evaluated. Moreover, very few, if any, studies have examined, in detail, the effect of burn injury and infection on the adaptive immune system. Thus, we examined the effect of burn and sepsis on adaptive immune cell populations and the effect of IL-15 SA treatment on the host response to infection. Methods Mice were subjected to a 35% total body surface area burn, followed by wound infection with Pseudomonas aeruginosa. In some experiments, IL-15 SA was administered after burn injury, but before infection. Leukocytes in spleen, liver and peritoneal cavity were characterized using flow cytometry. Bacterial clearance, organ injury and survival were also assessed. Results Burn wound infection led to a significant decline in total white blood cell and lymphocyte counts and induced organ injury and sepsis. Burn injury caused decline in CD4+ and CD8+ T cells in the spleen, which was worsened by infection. IL-15 treatment inhibited this decline and significantly increased cell numbers and activation, as determined by CD69 expression, of CD4+, CD8+, B, NK and NKT cells in the spleen and liver after burn injury. However, IL-15 SA treatment failed to prevent burn wound sepsis-induced loss of CD4+, CD8+, B, NK and NKT cells and failed to improve bacterial clearance and survival. Conclusion Cutaneous burn injury and infection cause significant adaptive immune dysfunction. IL-15

  19. TPL2 Kinase Is a Crucial Signaling Factor and Mediator of NKT Effector Cytokine Expression in Immune-Mediated Liver Injury.

    PubMed

    Vyrla, Dimitra; Nikolaidis, Georgios; Oakley, Fiona; Perugorria, Maria J; Tsichlis, Philip N; Mann, Derek A; Eliopoulos, Aristides G

    2016-05-15

    Invariant NKT (iNKT) cells represent a subset of innate-like T lymphocytes that function as orchestrators of hepatic inflammation underpinning liver damage. In this study, we demonstrate that TPL2, an MAP3 kinase that has mostly been appreciated for its physiological role in macrophage responses, is a signaling factor in CD3(+)NK1.1(+) iNKT cells and mediator of hepatic inflammation. Genetic ablation of TPL2 in the mouse ameliorates liver injury induced by Con A and impinges on hallmarks of NKT cell activation in the liver without affecting NKT cell development in the thymus. The pivotal role of TPL2 in iNKT cell functions is further endorsed by studies using the iNKT-specific ligand α-galactosylceramide, which causes mild hepatitis in the mouse in a TPL2-dependent manner, including production of the effector cytokines IL-4 and IFN-γ, accumulation of neutrophils and licensing and activation of other immune cell types in the liver. A TPL2 kinase inhibitor mirrors the effects of genetic ablation of TPL2 in vivo and uncovers ERK and Akt as the TPL2-regulated signaling pathways responsible for IL-4 and IFN-γ expression through the activation of the transcription factors JunB and NFAT. Collectively, these findings expand our understanding of the mechanisms of iNKT cell activation and suggest that modulation of TPL2 has the potential to minimize the severity of immune-driven liver diseases. PMID:27053764

  20. Disseminated Mycobacterium marinum Infection With a Destructive Nasal Lesion Mimicking Extranodal NK/T Cell Lymphoma

    PubMed Central

    Asakura, Takanori; Ishii, Makoto; Kikuchi, Taku; Kameyama, Kaori; Namkoong, Ho; Nakata, Noboru; Sugita, Kayoko; Tasaka, Sadatomo; Shimizu, Takayuki; Hoshino, Yoshihiko; Okamoto, Shinichiro; Betsuyaku, Tomoko; Hasegawa, Naoki

    2016-01-01

    Abstract Mycobacterium marinum is a ubiquitous waterborne organism that mainly causes skin infection in immunocompetent patients, and its disseminated infection is rare. Extranodal NK/T cell lymphoma, nasal type (ENKL) usually localizes at the nasal and/or paranasal area, but occasionally disseminates into the skin/soft tissue and gastrointestinal tract. Compromised immunity is a risk factor for developing nontuberculous mycobacterial (NTM) infection and malignant lymphoma, and the 2 diseases may share similar clinical presentation; however, only a few reports have described NTM infection mimicking malignant lymphoma. A 43-year-old Japanese man presented to our hospital complaining of multiple progressive skin nodules and purulent nasal discharge for 3 weeks. He was diagnosed with Crohn disease with refractory enteropathic arthritis and has been treated with anti-tumor necrosis factor alpha agents for 25 years. Fiberoptic nasal examination revealed septal perforation with hemorrhagic mucus and purulent rhinorrhea. Histological examination of the nasal septum revealed the infiltration of atypical medium-to-large-sized cells with erosion. The cells were positive for cytoplasmic CD3, granzyme B, and Epstein–Barr virus-encoded small RNA. Histological examination of the skin nodules and auricle also showed infiltration of atypical lymphocytes. The patient was tentatively diagnosed with ENKL, and chemotherapy was considered. However, the skin lesions decreased in size after discontinuation of immunosuppressive agents and minocycline administration. Two weeks later, nasal septum and lavage fluid and left leg skin cultures were positive for M marinum, and minocycline was discontinued. The skin and the nasal lesions improved after 2 months. To the best of our knowledge, this is the first case of disseminated M marinum infection with a destructive nasal lesion mimicking ENKL. The differentiation between M marinum infection and ENKL is clinically important because

  1. Differential Recognition of CD1d-[alpha]-Galactosyl Ceramide by the V[beta]8.2 and V[beta]7 Semi-invariant NKT T Cell Receptors

    SciTech Connect

    Pellicci, Daniel G.; Patel, Onisha; Kjer-Nielsen, Lars; Pang, Siew Siew; Sullivan, Lucy C.; Kyparissoudis, Konstantinos; Brooks, Andrew G.; Reid, Hugh H.; Gras, Stephanie; Lucet, Isabelle S.; Koh, Ruide; Smyth, Mark J.; Mallevaey, Thierry; Matsuda, Jennifer L.; Gapin, Laurent; McCluskey, James; Godfrey, Dale I.; Rossjohn, Jamie; PMCI-A; Monash; UCHSC; Melbourne

    2009-09-02

    The semi-invariant natural killer T cell receptor (NKT TCR) recognizes CD1d-lipid antigens. Although the TCR{alpha} chain is typically invariant, the {beta} chain expression is more diverse, where three V{beta} chains are commonly expressed in mice. We report the structures of V{alpha}14-V{beta}8.2 and V{alpha}14-V{beta}7 NKT TCRs in complex with CD1d-{alpha}-galactosylceramide ({alpha}-GalCer) and the 2.5 {angstrom} structure of the human NKT TCR-CD1d-{alpha}-GalCer complex. Both V{beta}8.2 and V{beta}7 NKT TCRs and the human NKT TCR ligated CD1d-{alpha}-GalCer in a similar manner, highlighting the evolutionarily conserved interaction. However, differences within the V{beta} domains of the V{beta}8.2 and V{beta}7 NKT TCR-CD1d complexes resulted in altered TCR{beta}-CD1d-mediated contacts and modulated recognition mediated by the invariant {alpha} chain. Mutagenesis studies revealed the differing contributions of V{beta}8.2 and V{beta}7 residues within the CDR2{beta} loop in mediating contacts with CD1d. Collectively we provide a structural basis for the differential NKT TCR V{beta} usage in NKT cells.

  2. A prognostic model based on pretreatment platelet lymphocyte ratio for stage IE/IIE upper aerodigestive tract extranodal NK/T cell lymphoma, nasal type.

    PubMed

    Wang, Ke-feng; Chang, Bo-yang; Chen, Xiao-qin; Liu, Pan-pan; Wuxiao, Zhi-jun; Wang, Zhi-hui; Li, Su; Jiang, Wen-qi; Xia, Zhong-jun

    2014-12-01

    Patients with stage IE/IIE natural killer T (NK/T) cell lymphomas have discrepant survival outcome. This study aims to establish a prognostic model based on the pretreatment platelet lymphocyte ratio (PLR) specifically for localized extranodal NK/T cell lymphoma to guide the therapy. We retrospectively analyzed the data of 252 patients with early-stage upper aerodigestive tract NK/T cell lymphoma. The 5-year overall survival rate in 252 patients was 67.1%. Prognostic factors for survival were female (P = 0.025; relative risk, 0.51; 95% CI 0.28-0.92), older age (P = 0.000; relative risk, 3.34; 95% CI 1.94-5.75), stage II(P = 0.020; relative risk, 1.79; 95% CI 1.10-2.91), lactate dehydrogenase (LDH) level (P = 0.009; relative risk, 2.00; 95% CI 1.19-3.35), and PLR (P = 0.020; relative risk, 1.77; 95% CI 1.10-2.87). Based on these five parameters, we identified three different risk groups: group 1(106 cases, 43.4%), no or one adverse factor; group 2(85 cases, 34.8%), two factors; group 3(53 cases, 21.7%), three to five factors. Five-year overall survival was 83.3% for group 1, 62.2% for group 2, and 43.1% for group 3 (P = 0.000). Compared with International Prognostic Index and Korean Prognostic Index, the new model has a better prognostic discrimination for the patients of stage IE/IIE upper aerodigestive tract NK/T cell lymphoma. The PLR-based prognosis model is useful to stratify patients with localized extranodal NK/T cell lymphoma into different risk groups and guide the treatment modalities selection. PMID:25377661

  3. Relationships between Th1 or Th2 iNKT Cell Activity and Structures of CD1d-Antigen Complexes: Meta-analysis of CD1d-Glycolipids Dynamics Simulations

    PubMed Central

    Laurent, Xavier; Renault, Nicolas; Farce, Amaury; Chavatte, Philippe; Hénon, Eric

    2014-01-01

    A number of potentially bioactive molecules can be found in nature. In particular, marine organisms are a valuable source of bioactive compounds. The activity of an α-galactosylceramide was first discovered in 1993 via screening of a Japanese marine sponge (Agelas mauritanius). Very rapidly, a synthetic glycololipid analogue of this natural molecule was discovered, called KRN7000. Associated with the CD1d protein, this α-galactosylceramide 1 (KRN7000) interacts with the T-cell antigen receptor to form a ternary complex that yields T helper (Th) 1 and Th2 responses with opposing effects. In our work, we carried out molecular dynamics simulations (11.5 µs in total) involving eight different ligands (conducted in triplicate) in an effort to find out correlation at the molecular level, if any, between chemical modulation of 1 and the orientation of the known biological response, Th1 or Th2. Comparative investigations of human versus mouse and Th1 versus Th2 data have been carried out. A large set of analysis tools was employed including free energy landscapes. One major result is the identification of a specific conformational state of the sugar polar head, which could be correlated, in the present study, to the biological Th2 biased response. These theoretical tools provide a structural basis for predicting the very different dynamical behaviors of α-glycosphingolipids in CD1d and might aid in the future design of new analogues of 1. PMID:25376021

  4. Antigen-Induced Increases in Pulmonary Mast Cell Progenitor Numbers Depend on IL-9 and CD1d-Restricted NKT Cells1

    PubMed Central

    Jones, Tatiana G.; Hallgren, Jenny; Humbles, Alison; Burwell, Timothy; Finkelman, Fred D.; Alcaide, Pilar; Austen, K. Frank; Gurish, Michael F.

    2009-01-01

    Pulmonary mast cell progenitor (MCp) numbers increase dramatically in sensitized and aerosolized Ag-challenged mice. This increase depends on CD4+ T cells, as no MCp increase occurs in the lungs of sensitized wild-type (WT) mice after mAb depletion of CD4+ but not CD8+ cells before aerosol Ag challenge. Neither the genetic absence of IL-4, IL-4Rα chain, STAT-6, IFN-γ, or IL-12p40 nor mAb blockade of IFN-γ, IL-3, IL-4, IL-5, IL-6, IL-10, IL-13, IL-17A, IL-12p40, or IL-12p40Rβ1 before Ag challenge in WT mice reduces the pulmonary MCp increase. However, sensitized and Ag-challenged IL-9-deficient mice and sensitized WT mice given mAb to IL-9 just before Ag challenge show significant reductions in elicited lung MCp/106 mononuclear cells of 47 and 66%, respectively. CD1d-deficient mice and WT mice receiving anti-CD1d before Ag challenge also show significant reductions of 65 and 59%, respectively, in elicited lung MCp/106 mononuclear cells, revealing an additional requirement for MCp recruitment. However, in Jα18-deficient mice, which lack only type 1 or invariant NKT cells, the increase in the numbers of lung MCp with Ag challenge was intact, indicating that their recruitment must be mediated by type 2 NKT cells. Furthermore, anti-CD1d treatment of IL-9-deficient mice or anti-IL-9 treatment of CD1d-deficient mice does not further reduce the significant partial impairment of MCp recruitment occurring with a single deficiency. These findings implicate type 2 NKT cells and IL-9 as central regulators that function in the same pathway mediating the Ag-induced increase in numbers of pulmonary MCp. PMID:19783672

  5. Preventing and curing citrulline-induced autoimmune arthritis in a humanized mouse model using a Th2-polarizing iNKT cell agonist.

    PubMed

    Walker, Kyle M; Rytelewski, Mateusz; Mazzuca, Delfina M; Meilleur, Shannon A; Mannik, Lisa A; Yue, David; Brintnell, William C; Welch, Ian; Cairns, Ewa; Haeryfar, S M Mansour

    2012-07-01

    Invariant natural killer T (iNKT) cells are innate lymphocytes with unique reactivity to glycolipid antigens bound to non-polymorphic CD1d molecules. They are capable of rapidly releasing pro- and/or anti-inflammatory cytokines and constitute attractive targets for immunotherapy of a wide range of diseases including autoimmune disorders. In this study, we have explored the beneficial effects of OCH, a Th2-polarizing glycolipid agonist of iNKT cells, in a humanized mouse model of rheumatoid arthritis (RA) in which citrullinated human proteins are targeted by autoaggressive immune responses in mice expressing an RA susceptibility human leukocyte antigen (HLA) DR4 molecule. We found for the first time that treatment with OCH both prevents and cures citrulline-induced autoimmune arthritis as evidenced by resolved ankle swelling and reversed histopathological changes associated with arthritis. Also importantly, OCH treatment blocked the arthritogenic capacity of citrullinated antigen-experienced splenocytes without compromising their global responsiveness or altering the proportion of splenic naturally occurring CD4(+)CD25(+)FoxP3(+) regulatory T cells. Interestingly, administering the Th1-promoting iNKT cell glycolipid ligand α-C-galactosylceramide into HLA-DR4 transgenic mice increased the incidence of arthritis in these animals and exacerbated their clinical symptoms, strongly suggesting a role for Th1 responses in the pathogenesis of citrulline-induced arthritis. Therefore, our findings indicate a role for Th1-mediated immunopathology in citrulline-induced arthritis and provide the first evidence that iNKT cell manipulation by Th2-skewing glycolipids may be of therapeutic value in this clinically relevant model, a finding that is potentially translatable to human RA. PMID:21912419

  6. Distinct Cytokine Profiles of Neonatal Natural Killer T Cells after Expansion with Subsets of Dendritic Cells

    PubMed Central

    Kadowaki, Norimitsu; Antonenko, Svetlana; Ho, Stephen; Rissoan, Marie-Clotilde; Soumelis, Vassili; Porcelli, Steven A.; Lanier, Lewis L.; Liu, Yong-Jun

    2001-01-01

    Natural killer T (NKT) cells are a highly conserved subset of T cells that have been shown to play a critical role in suppressing T helper cell type 1–mediated autoimmune diseases and graft versus host disease in an interleukin (IL)-4–dependent manner. Thus, it is important to understand how the development of IL-4– versus interferon (IFN)-γ–producing NKT cells is regulated. Here, we show that NKT cells from adult blood and those from cord blood undergo massive expansion in cell numbers (500–70,000-fold) during a 4-wk culture with IL-2, IL-7, phytohemagglutinin, anti-CD3, and anti-CD28 mAbs. Unlike adult NKT cells that preferentially produce both IL-4 and IFN-γ, neonatal NKT cells preferentially produce IL-4 after polyclonal activation. Addition of type 2 dendritic cells (DC2) enhances the development of neonatal NKT cells into IL-4+IFN-γ− NKT2 cells, whereas addition of type 1 dendritic cells (DC1) induces polarization towards IL-4−IFN-γ+ NKT1 cells. Adult NKT cells display limited plasticity for polarization induced by DC1 or DC2. Thus, newly generated NKT cells may possess the potent ability to develop into IL-4+IFN-γ− NKT2 cells in response to appropriate stimuli and may thereafter acquire the tendency to produce both IL-4 and IFN-γ. PMID:11369793

  7. Expansion of highly activated invariant natural killer T cells with altered phenotype in acute dengue infection.

    PubMed

    Kamaladasa, A; Wickramasinghe, N; Adikari, T N; Gomes, L; Shyamali, N L A; Salio, M; Cerundolo, V; Ogg, G S; Malavige, G Neelika

    2016-08-01

    Invariant natural killer T (iNKT) cells are capable of rapid activation and production of cytokines upon recognition of antigenic lipids presented by CD1d molecules. They have been shown to play a significant role in many viral infections and were observed to be highly activated in patients with acute dengue infection. In order to characterize further their role in dengue infection, we investigated the proportion of iNKT cells and their phenotype in adult patients with acute dengue infection. The functionality of iNKT cells in patients was investigated by both interferon (IFN)-γ and interleukin (IL)-4 ex-vivo enzyme-linked immunospot (ELISPOT) assays following stimulation with alpha-galactosyl-ceramide (αGalCer). We found that circulating iNKT cell proportions were significantly higher (P = 0·03) in patients with acute dengue when compared to healthy individuals and were predominantly of the CD4(+) subset. iNKT cells of patients with acute dengue had reduced proportions expressing CD8α and CD161 when compared to healthy individuals. The iNKT cells of patients were highly activated and iNKT activation correlated significantly with dengue virus-specific immunoglobulin (Ig)G antibody levels. iNKT cells expressing Bcl-6 (P = 0·0003) and both Bcl-6 and inducible T cell co-stimulator (ICOS) (P = 0·006) were increased significantly in patients when compared to healthy individuals. Therefore, our data suggest that in acute dengue infection there is an expansion of highly activated CD4(+) iNKT cells, with reduced expression of CD161 markers. PMID:26874822

  8. Influence of In Vitro IL-2 or IL-15 Alone or in Combination with Hsp 70 Derived 14-Mer Peptide (TKD) on the Expression of NK Cell Activatory and Inhibitory Receptors on Peripheral Blood T Cells, B Cells and NKT Cells.

    PubMed

    Hromadnikova, Ilona; Li, Shuang; Kotlabova, Katerina; Dickinson, Anne M

    2016-01-01

    Previous studies from Multhoff and colleagues reported that plasma membrane Hsp70 acts as a tumour-specific recognition structure for activated NK cells, and that the incubation of NK cells with Hsp70 and/or a 14-mer peptide derived from the N-terminal sequence of Hsp70 (TKDNNLLGRFELSG, TKD, aa 450-463) plus a low dose of IL-2 triggers NK cell proliferation and migration, and their capacity to kill cancer cells expressing membrane Hsp70. Herein, we have used flow cytometry to determine the influence of in vitro stimulation of peripheral blood mononuclear cells from healthy individuals with IL-2 or IL-15, either alone or in combination with TKD peptide on the cell surface expression of CD94, NK cell activatory receptors (CD16, NK2D, NKG2C, NKp30, NKp44, NKp46, NKp80, KIR2DL4, DNAM-1 and LAMP1) and NK cell inhibitory receptors (NKG2A, KIR2DL2/L3, LIR1/ILT-2 and NKR-P1A) by CD3+CD56+ (NKT), CD3+CD4+, CD3+CD8+ and CD19+ populations. NKG2D, DNAM-1, LAMP1 and NKR-P1A expression was upregulated after the stimulation with IL-2 or IL-15 alone or in combination with TKD in NKT, CD8+ T cells and B cells. CD94 was upregulated in NKT and CD8+ T cells. Concurrently, an increase in a number of CD8+ T cells expressing LIR1/ILT-2 and CD4+ T cells positive for NKR-P1A was observed. The proportion of CD8+ T cells that expressed NKG2D was higher after IL-2/TKD treatment, when compared with IL-2 treatment alone. In comparison with IL-15 alone, IL-15/TKD treatment increased the proportion of NKT cells that were positive for CD94, LAMP1 and NKRP-1A. The more potent effect of IL-15/TKD on cell surface expression of NKG2D, LIR1/ILT-2 and NKRP-1A was observed in B cells compared with IL-15 alone. However, this increase was not of statistical significance. IL-2/TKD induced significant upregulation of LAMP1 in CD8+ T cells compared with IL-2 alone. Besides NK cells, other immunocompetent cells present within the fraction of peripheral blood mononuclear cells were influenced by the treatment

  9. Influence of In Vitro IL-2 or IL-15 Alone or in Combination with Hsp 70 Derived 14-Mer Peptide (TKD) on the Expression of NK Cell Activatory and Inhibitory Receptors on Peripheral Blood T Cells, B Cells and NKT Cells

    PubMed Central

    Hromadnikova, Ilona; Li, Shuang; Kotlabova, Katerina; Dickinson, Anne M.

    2016-01-01

    Previous studies from Multhoff and colleagues reported that plasma membrane Hsp70 acts as a tumour-specific recognition structure for activated NK cells, and that the incubation of NK cells with Hsp70 and/or a 14-mer peptide derived from the N-terminal sequence of Hsp70 (TKDNNLLGRFELSG, TKD, aa 450–463) plus a low dose of IL-2 triggers NK cell proliferation and migration, and their capacity to kill cancer cells expressing membrane Hsp70. Herein, we have used flow cytometry to determine the influence of in vitro stimulation of peripheral blood mononuclear cells from healthy individuals with IL-2 or IL-15, either alone or in combination with TKD peptide on the cell surface expression of CD94, NK cell activatory receptors (CD16, NK2D, NKG2C, NKp30, NKp44, NKp46, NKp80, KIR2DL4, DNAM-1 and LAMP1) and NK cell inhibitory receptors (NKG2A, KIR2DL2/L3, LIR1/ILT-2 and NKR-P1A) by CD3+CD56+ (NKT), CD3+CD4+, CD3+CD8+ and CD19+ populations. NKG2D, DNAM-1, LAMP1 and NKR-P1A expression was upregulated after the stimulation with IL-2 or IL-15 alone or in combination with TKD in NKT, CD8+ T cells and B cells. CD94 was upregulated in NKT and CD8+ T cells. Concurrently, an increase in a number of CD8+ T cells expressing LIR1/ILT-2 and CD4+ T cells positive for NKR-P1A was observed. The proportion of CD8+ T cells that expressed NKG2D was higher after IL-2/TKD treatment, when compared with IL-2 treatment alone. In comparison with IL-15 alone, IL-15/TKD treatment increased the proportion of NKT cells that were positive for CD94, LAMP1 and NKRP-1A. The more potent effect of IL-15/TKD on cell surface expression of NKG2D, LIR1/ILT-2 and NKRP-1A was observed in B cells compared with IL-15 alone. However, this increase was not of statistical significance. IL-2/TKD induced significant upregulation of LAMP1 in CD8+ T cells compared with IL-2 alone. Besides NK cells, other immunocompetent cells present within the fraction of peripheral blood mononuclear cells were influenced by the treatment

  10. Phenotypic and functional analyses of NK and NKT-like populations during the early stages of chikungunya infection.

    PubMed

    Thanapati, Subrat; Das, Rumki; Tripathy, Anuradha S

    2015-01-01

    The aim of this study was to characterize NK (CD56(+)CD3(-)) and NKT-like cell (CD56(+)CD3(+)) responses early after chikungunya infection. Expression profiling and functional analysis of T/NK/NKT-like cells were performed on samples from 56 acute and 31 convalescent chikungunya patients and 56 control individuals. The percentages of NK cells were high in both patient groups, whereas NKT-like cell percentages were high only in the convalescent group. The percentages of NKp30(+)CD3(-)CD56(+), NKp30(+)CD3(+)CD56(+), CD244(+)CD3(-)CD56(+), and CD244(+)CD3(+)CD56(+)cells were high, whereas the percentages of NKG2D(+)CD3(-)CD56(+) and NKG2D(+)CD3(+)CD56(+)cells were low in both patient groups. The percentages of NKp44(+)CD3(-)CD56(+) cells were high in both patient groups, whereas the percentages of NKp44(+)CD3(+)CD56(+) cells were higher in the acute group than in convalescent and control groups. The percentages of NKp46(+)CD3(-)CD56(+) cells were high in both patient groups. Higher percentages of perforin(+)CD3(-)CD56(+) and perforin(+)CD3(+)CD56(+) cells were observed in acute and convalescent patients, respectively. Higher cytotoxic activity was observed in acute patients than in controls. IFN-γ expression on NK cells of convalescent patients and on NKT-like cells of both patient groups was indicative of the regulatory role of NK and NKT-like cells. Collectively, these data showed that higher expression of activating receptors on NK/NKT-like cells and perforin(+) NK cells in acute patients could be responsible for increased cytotoxicity. The observed expression of perforin(+) NK cells in the acute phase and IFN-γ(+) NKT-like cells in the subsequent convalescent stage showed that NK/NKT-like cells mount an early and efficient response to chikungunya virus. Further study of the molecular mechanisms that limit viral dissemination/establishment of chronic disease will aid in understanding how NK/NKT-like cells control chikungunya infection. PMID:26388848

  11. Phenotypic and functional analyses of NK and NKT-like populations during the early stages of chikungunya infection

    PubMed Central

    Thanapati, Subrat; Das, Rumki; Tripathy, Anuradha S.

    2015-01-01

    The aim of this study was to characterize NK (CD56+CD3−) and NKT-like cell (CD56+CD3+) responses early after chikungunya infection. Expression profiling and functional analysis of T/NK/NKT-like cells were performed on samples from 56 acute and 31 convalescent chikungunya patients and 56 control individuals. The percentages of NK cells were high in both patient groups, whereas NKT-like cell percentages were high only in the convalescent group. The percentages of NKp30+CD3−CD56+, NKp30+CD3+CD56+, CD244+CD3−CD56+, and CD244+CD3+CD56+cells were high, whereas the percentages of NKG2D+CD3−CD56+ and NKG2D+CD3+CD56+cells were low in both patient groups. The percentages of NKp44+CD3−CD56+ cells were high in both patient groups, whereas the percentages of NKp44+CD3+CD56+ cells were higher in the acute group than in convalescent and control groups. The percentages of NKp46+CD3−CD56+ cells were high in both patient groups. Higher percentages of perforin+CD3−CD56+ and perforin+CD3+CD56+ cells were observed in acute and convalescent patients, respectively. Higher cytotoxic activity was observed in acute patients than in controls. IFN-γ expression on NK cells of convalescent patients and on NKT-like cells of both patient groups was indicative of the regulatory role of NK and NKT-like cells. Collectively, these data showed that higher expression of activating receptors on NK/NKT-like cells and perforin+ NK cells in acute patients could be responsible for increased cytotoxicity. The observed expression of perforin+ NK cells in the acute phase and IFN-γ+ NKT-like cells in the subsequent convalescent stage showed that NK/NKT-like cells mount an early and efficient response to chikungunya virus. Further study of the molecular mechanisms that limit viral dissemination/establishment of chronic disease will aid in understanding how NK/NKT-like cells control chikungunya infection. PMID:26388848

  12. Thymus medulla fosters generation of natural Treg cells, invariant γδ T cells, and invariant NKT cells: What we learn from intrathymic migration

    PubMed Central

    Cowan, Jennifer E; Jenkinson, William E; Anderson, Graham

    2015-01-01

    The organization of the thymus into distinct cortical and medullary regions enables it to control the step-wise migration and development of immature T-cell precursors. Such a process provides access to specialized cortical and medullary thymic epithelial cells at defined stages of maturation, ensuring the generation of self-tolerant and MHC-restricted conventional CD4+ and CD8+ αβ T cells. The migratory cues and stromal cell requirements that regulate the development of conventional αβ T cells have been well studied. However, the thymus also fosters the generation of several immunoregulatory T-cell populations that form key components of both innate and adaptive immune responses. These include Foxp3+ natural regulatory T cells, invariant γδ T cells, and CD1d-restricted invariant natural killer T cells (iNKT cells). While less is known about the intrathymic requirements of these nonconventional T cells, recent studies have highlighted the importance of the thymus medulla in their development. Here, we review recent findings on the mechanisms controlling the intrathymic migration of distinct T-cell subsets, and relate this to knowledge of the microenvironmental requirements of these cells. PMID:25615828

  13. Complete remission after first-line radio-chemotherapy as predictor of survival in extranodal NK/T cell lymphoma

    PubMed Central

    2012-01-01

    Background Extranodal nasal-type NK/T-cell lymphoma is a rare and severe disease. Considering the rarity of this lymphoma in Europe, we conducted a multicentric retrospective study on nasal-type NK/T cell lymphoma to determine the optimal induction strategy and identify prognostic factors. Methods Thirty-six adult patients with nasal-type NK/T-cell lymphoma were recruited and assessed. In total, 80 % of patients were classified as having upper aerodigestive tract NK/T-cell lymphoma (UNKTL) and 20 % extra-upper aerodigestive tract NK/T-cell lymphoma (EUNKTL). Results For advanced-stage disease, chemotherapy alone (CT) was the primary treatment (84 % vs. 10 % for combined CT + radiation therapy (RT), respectively), while for early-stage disease, 50 % of patients received the combination of CT + RT and 50 % CT alone. Five-year overall survival (OS) and progression-free survival (PFS) rates were 39 % and 33 %. Complete remission (CR) rates were significantly higher when using CT + RT (90 %) versus CT alone (33 %) (p < 0.0001). For early-stage disease, CR rates were 37 % for CT alone versus 100 % for CT + RT. Quality of response was significantly associated with survival, with 5-year OS being 80 % for CR patients versus 0 % for progressive disease patients (p < 0.01). Conclusion Early RT concomitantly or sequentially with CT led to improved patient outcomes, with quality of initial response being the most important prognosticator for 5-year OS. PMID:22682004

  14. Co-delivery of PLGA encapsulated invariant NKT cell agonist with antigenic protein induce strong T cell-mediated antitumor immune responses

    PubMed Central

    Dölen, Yusuf; Kreutz, Martin; Gileadi, Uzi; Tel, Jurjen; Vasaturo, Angela; van Dinther, Eric A. W.; van Hout-Kuijer, Maaike A.; Cerundolo, Vincenzo; Figdor, Carl G.

    2016-01-01

    ABSTRACT Antitumor immunity can be enhanced by the coordinated release and delivery of antigens and immune-stimulating agents to antigen-presenting cells via biodegradable vaccine carriers. So far, encapsulation of TLR ligands and tumor-associated antigens augmented cytotoxic T cell (CTLs) responses. Here, we compared the efficacy of the invariant NKT (iNKT) cell agonist α-galactosylceramide (α-GalCer) and TLR ligands (R848 and poly I:C) as an adjuvant for the full length ovalbumin (OVA) in PLGA nanoparticles. We observed that OVA+α-GalCer nanoparticles (NP) are superior over OVA+TLR-L NP in generating and stimulating antigen-specific cytotoxic T lymphocytes without the need for CD4+ T cell help. Not only a 4-fold higher induction of antigen-specific T cells was observed, but also a more profound IFN-γ secretion was obtained by the addition α-GalCer. Surprisingly, we observed that mixtures of OVA containing NP with α-GalCer were ineffective, demonstrating that co-encapsulation of both α-GalCer and antigen within the same nanoparticle is essential for the observed T cell responses. Moreover, a single immunization with OVA+α-GalCer NP provided substantial protection from tumor formation and even delayed the growth of already established tumors, which coincided with a prominent and enhanced antigen-specific CD8+ T cell infiltration. The provided evidence on the advantage of antigen and α-GalCer coencapsulation should be considered in the design of future nanoparticle vaccines for therapeutic purposes. PMID:26942088

  15. Maternal low protein diet leads to dysregulation of placental iNKT cells and M1/M2 macrophage ratio, body weight loss in male, neonate Sprague-Dawley rats and increased UCP-1 mediated thermogenesis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Placental immune cells provide cytokines and growth factors that are necessary for placenta development and function. Invariant natural killer T (iNKT) cells are innate cells specific for glycolipid antigens presented by the CD1d molecule and secrete Th1 cytokines in the placenta, suggesting an imm...

  16. Pollution of mycological surfaces in hospital emergency departments correlates positively with blood NKT CD3(+) 16(+) 56(+) and negatively with CD4(+) cell levels of their staff.

    PubMed

    Suska, Milena; Lewicki, Sławomir; Kiepura, Anna; Winnicka, Izabela; Leszczyński, Paweł; Bielawska-Drózd, Agata; Cieślik, Piotr; Kubiak, Leszek; Depczyńska, Daria; Brewczyńska, Aleksandra; Skopińska-Różewska, Ewa; Kocik, Janusz

    2016-01-01

    The aim of the present study was the assessment of the putative influence of yeast and filamentous fungi in healthcare and control (office) workplaces (10 of each kind) on immune system competence measured by NK (natural killer), CD4(+), and NKT (natural killer T lymphocyte) cell levels in the blood of the personnel employed at these workplaces. Imprints from floors and walls were collected in winter. The blood was taken in spring the following year, from 40 men, 26 to 53 years old, healthcare workers of hospital emergency departments (HED), who had been working for at least five years in their current positions, and from 36 corresponding controls, working in control offices. Evaluation of blood leukocyte subpopulations was done by flow cytometry. The qualitative analysis of the surface samples revealed a prevalence of strains belonging to Aspergillus spp. and Penicillium spp. genus. There was no statistically significant difference between the level of NKT; however, the percentage of NK cells was lower in the blood of HED workers than in the blood of offices personnel. Spearman analysis revealed the existence of positive correlation (r = 0.4677, p = 0.002) between the total CFU/25 cm(2) obtained by imprinting method from walls and floors of HED and the percentage of NKT (CD3(+)16(+)56(+)) lymphocytes collected from the blood of their personnel, and negative correlation (r = -0. 3688, p = 0.019) between this parameter of fungal pollution and the percentage of CD4(+) lymphocytes in the blood of HED staff. No other correlations were found. PMID:27095925

  17. Pollution of mycological surfaces in hospital emergency departments correlates positively with blood NKT CD3+ 16+ 56+ and negatively with CD4+ cell levels of their staff

    PubMed Central

    Suska, Milena; Kiepura, Anna; Winnicka, Izabela; Leszczyński, Paweł; Bielawska-Drózd, Agata; Cieślik, Piotr; Kubiak, Leszek; Depczyńska, Daria; Brewczyńska, Aleksandra; Skopińska-Różewska, Ewa; Kocik, Janusz

    2016-01-01

    The aim of the present study was the assessment of the putative influence of yeast and filamentous fungi in healthcare and control (office) workplaces (10 of each kind) on immune system competence measured by NK (natural killer), CD4+, and NKT (natural killer T lymphocyte) cell levels in the blood of the personnel employed at these workplaces. Imprints from floors and walls were collected in winter. The blood was taken in spring the following year, from 40 men, 26 to 53 years old, healthcare workers of hospital emergency departments (HED), who had been working for at least five years in their current positions, and from 36 corresponding controls, working in control offices. Evaluation of blood leukocyte subpopulations was done by flow cytometry. The qualitative analysis of the surface samples revealed a prevalence of strains belonging to Aspergillus spp. and Penicillium spp. genus. There was no statistically significant difference between the level of NKT; however, the percentage of NK cells was lower in the blood of HED workers than in the blood of offices personnel. Spearman analysis revealed the existence of positive correlation (r = 0.4677, p = 0.002) between the total CFU/25 cm2 obtained by imprinting method from walls and floors of HED and the percentage of NKT (CD3+16+56+) lymphocytes collected from the blood of their personnel, and negative correlation (r = –0. 3688, p = 0.019) between this parameter of fungal pollution and the percentage of CD4+ lymphocytes in the blood of HED staff. No other correlations were found. PMID:27095925

  18. α/β–T Cell Receptor (TCR)+CD4−CD8− (NKT) Thymocytes Prevent Insulin-dependent Diabetes Mellitus in Nonobese Diabetic (NOD)/Lt Mice by the Influence of Interleukin (IL)-4 and/or IL-10

    PubMed Central

    Hammond, Kirsten J.L.; Poulton, Lynn D.; Palmisano, Linda J.; Silveira, Pablo A.; Godfrey, Dale I.; Baxter, Alan G.

    1998-01-01

    We have previously shown that nonobese diabetic (NOD) mice are selectively deficient in α/β-T cell receptor (TCR)+CD4−CD8− NKT cells, a defect that may contribute to their susceptibility to the spontaneous development of insulin-dependent diabetes mellitus (IDDM). The role of NKT cells in protection from IDDM in NOD mice was studied by the infusion of thymocyte subsets into young female NOD mice. A single intravenous injection of 106 CD4−/lowCD8− or CD4−CD8− thymocytes from female (BALB/c × NOD)F1 donors protected intact NOD mice from the spontaneous onset of clinical IDDM. Insulitis was still present in some recipient mice, although the cell infiltrates were principally periductal and periislet, rather than the intraislet pattern characteristic of insulitis in unmanipulated NOD mice. Protection was not associated with the induction of “allogenic tolerance” or systemic autoimmunity. Accelerated IDDM occurs after injection of splenocytes from NOD donors into irradiated adult NOD recipients. When α/β-TCR+ and α/β-TCR− subsets of CD4−CD8− thymocytes were transferred with diabetogenic splenocytes and compared for their ability to prevent the development of IDDM in irradiated adult recipients, only the α/β-TCR+ population was protective, confirming that NKT cells were responsible for this activity. The protective effect in the induced model of IDDM was neutralized by anti–IL-4 and anti–IL-10 monoclonal antibodies in vivo, indicating a role for at least one of these cytokines in NKT cell-mediated protection. These results have significant implications for the pathogenesis and potential prevention of IDDM in humans. PMID:9529321

  19. Primary NK/T cell lymphoma nasal type of the colon

    PubMed Central

    Mahuad, Carolina Valeria; Bilbao, Érica Rojas; Garate, Gonzalo Martín; de los Ángeles Vicente Repáraz, María; del Olmo, Mercedes; Casali, Claudia Érica; Zerga, Marta Elisa; Chirife, Ana María; Cicco, Juan Alberto

    2013-01-01

    Since nasal NK/T-cell lymphoma and NK/T-cell lymphoma nasal type are rare diseases, colonic involvement has seldom been seen. We report a case of a patient with a primary NK/T-cell lymphoma nasal type of the colon. The patient had no history of malignant diseases and was diagnosed after exhaustive study in the context of fever of unknown origin. The first therapeutic approach followed the DA-EPOCH-protocol: etoposide, prednisone, doxor-rubicin, vincristine and cyclophosphamide. The persistence of constitutional symptoms after the first treatment course motivated the switch to a second line following the SMILE-protocol: dexamethasone, metotrexate, ifosfamide, E.coli L-asparaginase, and etoposide. Despite intensive chemotherapy, the patient died 2 months after the diagnose of an extranodal NK/T-cell lymphoma of the colon and 4 months after the first symptomatic appearance of disease. PMID:23772308

  20. Interleukin-2 gene transfer potentiates the alpha-galactosylceramide-stimulated antitumor effect by the induction of TRAIL in NKT and NK cells in mouse models of subcutaneous and metastatic carcinoma.

    PubMed

    Nishihori, Yoshiki; Kato, Kazunori; Tanaka, Maki; Okamoto, Tetsuro; Hagiwara, Seiya; Araki, Naoko; Kogawa, Katsuhisa; Kuribayashi, Kageaki; Nakamura, Kiminori; Niitsu, Yoshiro

    2009-09-01

    Alpha-Galactosylceramide (alpha-GalCer) is a potent CD1d ligand that activates natural killer like T-cells (NKT), leading to the production of helper T (Th) 1 and Th2 cytokines that mediate various immunemodulatory and antitumor effects. Here, we determined whether the administration of adenovirus-vector-encoding mouse interleukin-2 (AdmIL-2) can augment the antitumor effect of alpha-GalCer on subcutaneous and metastatic tumors in mice. Mice were intraperitoneally injected with alpha-GalCer on days 7, 10 and 13 after tumor inoculation, with or without intratumoral injection of AdmIL-2 on day 7. alpha-GalCer treatment increased the serum levels of interferon-gamma, while intratumoral injection of AdmIL-2 elevated serum IL-2 levels. A combination of alpha-GalCer and AdmIL-2 (alpha-GalCer/AdmIL-2) inhibited the in vivo tumor growth and improved the survival of tumor-bearing mice, as compared to the use of a single agent. Experiments on spontaneous metastasis models revealed that alpha-GalCer/AdmIL-2 reduced lung metastasis and prolonged survival, as compared to control groups. In addition, the splenic and liver mononuclear cells from mice treated with alpha-GalCer/AdmIL-2 showed enhanced cytolytic activity against NK-sensitive YAC-1 and NK-resistant 3LL tumors. Moreover, alpha-GalCer/AdmIL-2 treatment expanded the absolute numbers of lung and liver NK, NKT and T-cells as well as the TNF-related apoptosis-inducing ligand (TRAIL) expression of these cells. This study shows the efficacy of alpha-GalCer/AdmIL-2 immunomodulatory therapy, and provides a cellular mechanism on how it exerts the antitumor effects. PMID:19901518

  1. Assessment of Some Immune Parameters in Occupationally Exposed Nuclear Power Plants Workers: Flowcytometry Measurements of T, B, NK and NKT Cells.

    PubMed

    Gyuleva, Ilona; Panova, Delyana; Djounova, Jana; Rupova, Ivanka; Penkova, Kalina

    2015-01-01

    The purpose of this article is to analyze the results of a 10-year survey of the radiation effects of some immune parameters of occupationally exposed personnel from the Nuclear Power Plant "Kozloduy", Bulgaria. 438 persons working in NPP with cumulative doses between 0.06 mSv and 766.36mSv and a control group with 65 persons were studied. Flow cytometry measurements of T, B, natural killer (NK) and natural killer T (NKT) cell lymphocyte populations were performed. Data were interpreted with regard to cumulative doses, length of service and age. The average values of the studied parameters of cellular immunity were in the reference range relative to age and for most of the workers were not significantly different from the control values. Low doses of ionizing radiation showed some trends of change in the number of CD3+CD4+ helper-inducer lymphocytes, CD3+ CD8+ and NKT cell counts. The observed changes in some of the studied parameters could be interpreted in terms of adaptation processes at low doses. At doses above 100-200 mSv, compensatory mechanisms might be involved to balance deviations in lymphocyte subsets. The observed variations in some cases could not be attributed only to the radiation exposure because of the impact of a number of other exogenous and endogenous factors on the immune system. PMID:26675014

  2. Different subsets of natural killer T cells may vary in their roles in health and disease

    PubMed Central

    Kumar, Vipin; Delovitch, Terry L

    2014-01-01

    Natural killer T cells (NKT) can regulate innate and adaptive immune responses. Type I and type II NKT cell subsets recognize different lipid antigens presented by CD1d, an MHC class-I-like molecule. Most type I NKT cells express a semi-invariant T-cell receptor (TCR), but a major subset of type II NKT cells reactive to a self antigen sulphatide use an oligoclonal TCR. Whereas TCR-α dominates CD1d-lipid recognition by type I NKT cells, TCR-α and TCR-β contribute equally to CD1d-lipid recognition by type II NKT cells. These variable modes of NKT cell recognition of lipid–CD1d complexes activate a host of cytokine-dependent responses that can either exacerbate or protect from disease. Recent studies of chronic inflammatory and autoimmune diseases have led to a hypothesis that: (i) although type I NKT cells can promote pathogenic and regulatory responses, they are more frequently pathogenic, and (ii) type II NKT cells are predominantly inhibitory and protective from such responses and diseases. This review focuses on a further test of this hypothesis by the use of recently developed techniques, intravital imaging and mass cytometry, to analyse the molecular and cellular dynamics of type I and type II NKT cell antigen-presenting cell motility, interaction, activation and immunoregulation that promote immune responses leading to health versus disease outcomes. PMID:24428389

  3. Elevated levels of invariant natural killer T-cell and natural killer cell activation correlate with disease progression in HIV-1 and HIV-2 infections

    PubMed Central

    Bächle, Susanna M.; Malone, David F.G.; Buggert, Marcus; Karlsson, Annika C.; Isberg, Per-Erik; Biague, Antonio J.; Norrgren, Hans; Medstrand, Patrik; Moll, Markus; Sandberg, Johan K.; Jansson, Marianne

    2016-01-01

    Objective: In this study, we aimed to investigate the frequency and activation of invariant natural killer T (iNKT) cells and natural killer (NK) cells among HIV-1, HIV-2, or dually HIV-1/HIV-2 (HIV-D)-infected individuals, in relation to markers of disease progression. Design: Whole blood samples were collected from treatment-naive HIV-1 (n = 23), HIV-2 (n = 34), and HIV-D (n = 11) infected individuals, as well as HIV-seronegative controls (n = 25), belonging to an occupational cohort in Guinea-Bissau. Methods: Frequencies and activation levels of iNKT and NK cell subsets were analysed using multicolour flow cytometry, and results were related to HIV-status, CD4+ T-cell levels, viral load, and T-cell activation. Results: HIV-1, HIV-D, and viremic HIV-2 individuals had lower numbers of CD4+ iNKT cells in circulation compared with seronegative controls. Numbers of CD56bright NK cells were also reduced in HIV-infected individuals as compared with control study participants. Notably, iNKT cell and NK cell activation levels, assessed by CD38 expression, were increased in HIV-1 and HIV-2 single, as well as dual, infections. HIV-2 viremia was associated with elevated activation levels in CD4+ iNKT cells, CD56bright, and CD56dim NK cells, as compared with aviremic HIV-2 infection. Additionally, disease markers such as CD4+ T-cell percentages, viral load, and CD4+ T-cell activation were associated with CD38 expression levels of both iNKT and NK cells, which activation levels also correlated with each other. Conclusion: Our data indicate that elevated levels of iNKT-cell and NK-cell activation are associated with viremia and disease progression markers in both HIV-1 and HIV-2 infections. PMID:27163705

  4. Exacerbated Th2-mediated airway inflammation and hyperresponsiveness in autoimmune diabetes-prone NOD mice: a critical role for CD1d-dependent NKT cells.

    PubMed

    Araujo, Luiza M; Lefort, Jean; Nahori, Marie-Anne; Diem, Séverine; Zhu, Ren; Dy, Michel; Leite-de-Moraes, Maria C; Bach, J F; Vargaftig, B Boris; Herbelin, André

    2004-02-01

    The NOD mouse has proved to be a relevant model of insulin-dependent diabetes mellitus, closely resembling the human disease. However, it is unknown whether this strain presents a general biastoward Th1-mediated autoimmunity or remains capable of mounting complete Th2-mediated responses. Here, we show that NOD mice have the capacity to develop a typical Th2-mediated disease, namely experimental allergic asthma. In contrast to what might have been expected, they even developed a stronger Th2-mediated pulmonary inflammatory response than BALB/c mice, a strain that shows a typical Th2 bias in this model. Thus, after allergen sensitization and intra-nasal challenge, the typical features of experimental asthma were exacerbated in NOD mice, including enhanced bronchopulmonary responsiveness, mucus production and eosinophilic inflammation in the lungs as well as specific IgE titers in serum. These hallmarks of allergic asthma were associated with increased IL-4, IL-5, IL-13 and eotaxin production in the lungs, as compared with BALB/c mice. Notwithstanding their quantitative and functional defect in NOD mice, CD1d-dependent NKT cells contribute to aggravate the disease, since in OVA-immunized CD1d(-/-) NOD mice, which are deficient in this particular T cell subset, airway eosinophilia was clearly diminished relative to NOD littermates. This is the first evidence that autoimmune diabetes-prone NOD mice can also give rise to enhanced Th2-mediated responses and might thus provide a useful model for the study of common genetic and cellular components, including NKT cells that contribute to both asthma and type 1 diabetes. PMID:14768037

  5. KLRG+ invariant natural killer T cells are long-lived effectors.

    PubMed

    Shimizu, Kanako; Sato, Yusuke; Shinga, Jun; Watanabe, Takashi; Endo, Takaho; Asakura, Miki; Yamasaki, Satoru; Kawahara, Kazuyoshi; Kinjo, Yuki; Kitamura, Hiroshi; Watarai, Hiroshi; Ishii, Yasuyuki; Tsuji, Moriya; Taniguchi, Masaru; Ohara, Osamu; Fujii, Shin-ichiro

    2014-08-26

    Immunological memory has been regarded as a unique feature of the adaptive immune response mediated in an antigen-specific manner by T and B lymphocytes. However, natural killer (NK) cells and γδT cells, which traditionally are classified as innate immune cells, have been shown in recent studies to have hallmark features of memory cells. Invariant NKT cell (iNKT cell)-mediated antitumor effects indicate that iNKT cells are activated in vivo by vaccination with iNKT cell ligand-loaded CD1d(+) cells, but not by vaccination with unbound NKT cell ligand. In such models, it previously was thought that the numbers of IFN-γ-producing cells in the spleen returned to the basal level around 1 wk after the vaccination. In the current study, we demonstrate the surprising presence of effector memory-like iNKT cells in the lung. We found long-term antitumor activity in the lungs of mice was enhanced after vaccination with iNKT cell ligand-loaded dendritic cells. Further analyses showed that the KLRG1(+) (Killer cell lectin-like receptor subfamily G, member 1-positive) iNKT cells coexpressing CD49d and granzyme A persisted for several months and displayed a potent secondary response to cognate antigen. Finally, analyses of CDR3β by RNA deep sequencing demonstrated that some particular KLRG1(+) iNKT-cell clones accumulated, suggesting the selection of certain T-cell receptor repertoires by an antigen. The current findings identifying effector memory-like KLRG1(+) iNKT cells in the lung could result in a paradigm shift regarding the basis of newly developed extrathymic iNKT cells and could contribute to the future development of antitumor immunotherapy by uniquely energizing iNKT cells. PMID:25118276

  6. Synthetic glycolipid activators of natural killer T cells as immunotherapeutic agents

    PubMed Central

    Carreño, Leandro J; Saavedra-Ávila, Noemí A; Porcelli, Steven A

    2016-01-01

    Certain types of glycolipids have been found to have remarkable immunomodulatory properties as a result of their ability to activate specific T lymphocyte populations with an extremely wide range of immune effector properties. The most extensively studied glycolipid reactive T cells are known as invariant natural killer T (iNKT) cells. The antigen receptors of these cells specifically recognize certain glycolipids, most notably glycosphingolipids with α-anomeric monosaccharides, presented by the major histocompatibility complex class I-like molecule CD1d. Once activated, iNKT cells can secrete a very diverse array of pro- and anti-inflammatory cytokines to modulate innate and adaptive immune responses. Thus, glycolipid-mediated activation of iNKT cells has been explored for immunotherapy in a variety of disease states, including cancer and a range of infections. In this review, we discuss the design of synthetic glycolipid activators for iNKT cells, their impact on adaptive immune responses and their use to modulate iNKT cell responses to improve immunity against infections and cancer. Current challenges in translating results from preclinical animal studies to humans are also discussed. PMID:27195112

  7. Mechanisms of Innate Lymphoid Cell and Natural Killer T Cell Activation during Mucosal Inflammation

    PubMed Central

    Altmayer, Nora

    2014-01-01

    Mucosal surfaces in the airways and the gastrointestinal tract are critical for the interactions of the host with its environment. Due to their abundance at mucosal tissue sites and their powerful immunomodulatory capacities, the role of innate lymphoid cells (ILCs) and natural killer T (NKT) cells in the maintenance of mucosal tolerance has recently moved into the focus of attention. While NKT cells as well as ILCs utilize distinct transcription factors for their development and lineage diversification, both cell populations can be further divided into three polarized subpopulations reflecting the distinction into Th1, Th2, and Th17 cells in the adaptive immune system. While bystander activation through cytokines mediates the induction of ILC and NKT cell responses, NKT cells become activated also through the engagement of their canonical T cell receptors (TCRs) by (glyco)lipid antigens (cognate recognition) presented by the atypical MHC I like molecule CD1d on antigen presenting cells (APCs). As both innate lymphocyte populations influence inflammatory responses due to the explosive release of copious amounts of different cytokines, they might represent interesting targets for clinical intervention. Thus, we will provide an outlook on pathways that might be interesting to evaluate in this context. PMID:24987710

  8. Interleukin-13 Pathway Alterations Impair Invariant Natural Killer T-Cell-Mediated Regulation of Effector T Cells in Type 1 Diabetes.

    PubMed

    Usero, Lorena; Sánchez, Ana; Pizarro, Eduarda; Xufré, Cristina; Martí, Mercè; Jaraquemada, Dolores; Roura-Mir, Carme

    2016-08-01

    Many studies have shown that human natural killer T (NKT) cells can promote immunity to pathogens, but their regulatory function is still being investigated. Invariant NKT (iNKT) cells have been shown to be effective in preventing type 1 diabetes in the NOD mouse model. Activation of plasmacytoid dendritic cells, modulation of B-cell responses, and immune deviation were proposed to be responsible for the suppressive effect of iNKT cells. We studied the regulatory capacity of human iNKT cells from control subjects and patients with type 1 diabetes (T1D) at disease clinical onset. We demonstrate that control iNKT cells suppress the proliferation of effector T cells (Teffs) through a cell contact-independent mechanism. Of note, suppression depended on the secretion of interleukin-13 (IL-13) by iNKT cells because an antibody blocking this cytokine resulted from the abrogation of Teff suppression; however, T1D-derived iNKT cells showed impaired regulation that could be attributed to the decrease in IL-13 secretion. Thus, alteration of the IL-13 pathway at disease onset may lead to the progression of the autoimmune response in T1D. Advances in the study of iNKT cells and the selection of agonists potentiating IL-13 secretion should permit new therapeutic strategies to prevent the development of T1D. PMID:27207542

  9. CXCL16-positive dendritic cells enhance invariant natural killer T cell-dependent IFNγ production and tumor control

    PubMed Central

    Veinotte, Linnea; Gebremeskel, Simon; Johnston, Brent

    2016-01-01

    ABSTRACT Crosstalk interactions between dendritic cells (DCs) and invariant natural killer T (iNKT) cells are important in regulating antitumor responses elicited by glycolipid antigens. iNKT cells constitutively express the chemokine receptor CXCR6, while cytokine-activated DCs upregulate the transmembrane chemokine ligand, CXCL16. This study examined the co-stimulatory role of CXCR6/CXCL16 interactions in glycolipid-dependent iNKT cell activation and tumor control. Spleen and liver DCs in wild-type mice, but not iNKT cell deficient (Jα18−/−) mice, transiently upregulated surface CXCL16 following in vivo administration of the glycolipid antigen α-galactosylceramide. Recombinant CXCL16 did not directly induce iNKT cell activation in vitro but enhanced interferon (IFN)-γ production when mouse or human iNKT cells were stimulated with plate-bound anti-CD3. Compared with glycolipid-loaded CXCL16neg DCs, CXCL16hi DCs induced higher levels of IFNγ production in iNKT cell cultures and following adoptive transfer in vivo. The number of IFNγ+ iNKT cells and expansion of T-bet+ iNKT cells were reduced in vivo when CXCL16−/− DCs were used to activate iNKT cells. Enhanced IFNγ production in vivo was not dependent on CXCR6 expression on natural killer (NK) cells. Adoptive transfer of glycolipid-loaded CXCL16hi DCs provided superior protection against tumor metastasis compared to CXCL16neg DC transfers. Similarly, wild-type DCs provided superior protection against metastasis compared with CXCL16−/− DCs. These experiments implicate an important role for CXCR6/CXCL16 interactions in regulating iNKT cell IFNγ production and tumor control. The selective use of CXCL16hi DCs in adoptive transfer immunotherapies may prove useful for enhancing T helper (Th) type 1 responses and clinical outcomes in cancer patients. PMID:27471636

  10. Analyzing Antigen Recognition by Natural Killer T Cells

    PubMed Central

    Zeissig, Sebastian; Olszak, Torsten; Melum, Espen; Blumberg, Richard S.

    2013-01-01

    Natural Killer T (NKT) cells are a subset of T lymphocytes that recognize a wide variety of lipid antigens presented by CD1 molecules. NKT cells exhibit rapid activation after recognition of cognate antigens, secrete abundant amounts of T helper (Th) 1, Th2, and Th17 cytokines within hours of activation and shape the immune response through subsequent activation of dendritic, NK, T and B cells. NKT cells therefore play central roles in antimicrobial and anticancer immunity and in modulation of various autoimmune disorders. Consequently, recent research has focused on the discovery of microbial and self-antigens involved in NKT cell activation. In this chapter, we discuss different strategies for studying antigen recognition by NKT cells including CD1d tetramer-based approaches and in vitro assays characterizing NKT cell activation in response to lipid antigen presentation. While toll-like receptor (TLR) agonists and cytokines such as IL-12 are critical for NKT cell activation in vivo, particularly in the context of microbial infection, methods for detection of TLR- and cytokine-dependent NKT cell activation will not be discussed in this section. PMID:23329514

  11. Invariant natural killer T cells: bridging innate and adaptive immunity

    PubMed Central

    Parekh, Vrajesh V.; Wu, Lan

    2013-01-01

    Cells of the innate immune system interact with pathogens via conserved pattern-recognition receptors, whereas cells of the adaptive immune system recognize pathogens through diverse, antigen-specific receptors that are generated by somatic DNA rearrangement. Invariant natural killer T (iNKT) cells are a subset of lymphocytes that bridge the innate and adaptive immune systems. Although iNKT cells express T cell receptors that are generated by somatic DNA rearrangement, these receptors are semi-invariant and interact with a limited set of lipid and glycolipid antigens, thus resembling the pattern-recognition receptors of the innate immune system. Functionally, iNKT cells most closely resemble cells of the innate immune system, as they rapidly elicit their effector functions following activation, and fail to develop immunological memory. iNKT cells can become activated in response to a variety of stimuli and participate in the regulation of various immune responses. Activated iNKT cells produce several cytokines with the capacity to jump-start and modulate an adaptive immune response. A variety of glycolipid antigens that can differentially elicit distinct effector functions in iNKT cells have been identified. These reagents have been employed to test the hypothesis that iNKT cells can be harnessed for therapeutic purposes in human diseases. Here, we review the innate-like properties and functions of iNKT cells and discuss their interactions with other cell types of the immune system. PMID:20734065

  12. Contribution of lipid-reactive natural killer T cells to obesity-associated inflammation and insulin resistance.

    PubMed

    Wu, Lan; Van Kaer, Luc

    2013-01-01

    Obesity is associated with a low-grade, chronic inflammation that promotes the development of a variety of diseases, most notably type 2 diabetes. A number of cell types of the innate and adaptive immune systems have been implicated in this process. Recent studies have focused on the role of natural killer T (NKT) cells, a subset of T lymphocytes that react with lipids, in the development of obesity-associated diseases. These studies have shown that invariant NKT (iNKT) cells, a population of NKT cells expressing a semi-invariant T cell receptor, become rapidly activated in response to lipid excess, and that these cells influence the capacity of other leukocytes to produce cytokines during the progression of obesity. The role of NKT cells in obesity-associated inflammation and insulin resistance has been investigated using NKT cell-deficient animals, adoptive transfer of NKT cells and an iNKT cell agonist. While divergent results have been obtained, it is now clear that NKT cells can modulate the inflammatory milieu in obesity, suggesting that these cells could be targeted for therapeutic intervention in obesity-associated diseases. PMID:23700548

  13. Activation of CD1d-restricted natural killer T cells can inhibit cancer cell proliferation during chemotherapy by promoting the immune responses in murine mesothelioma.

    PubMed

    Wu, Licun; Yun, Zhihong; Tagawa, Tetsuzo; De la Maza, Luis; Wu, Matthew Onn; Yu, Julie; Zhao, Yidan; de Perrot, Marc

    2014-12-01

    We studied the impact of natural killer T (NKT) cell activation by alpha-galactocysylceramide (α-GalCer, α-GC) on cancer cell repopulation during chemotherapy in murine mesothelioma. The number of NKT cells was found to be increased during the development of murine mesothelioma. NKT cells specifically recognize α-GC through CD1d resulting in their activation and expansion. Tumor-bearing mice were treated with chemotherapy once weekly, and α-GC was followed after each cycle of chemotherapy. Anti-tumor effect was evaluated on wild-type (WT) and CD1d knockout (CD1dKO) mice. Cancer cell proliferation and apoptosis were evaluated by Ki67 and TUNEL immunohistochemistry. CD4(+) and CD8(+) T cell proportion and activation in tumor, spleen, draining lymph node and peripheral blood were determined by flow cytometry, and gene expression of activated T cell-related cytokines was quantified by reverse transcription PCR. NKT cells were identified by CD1d-α-GC-tetramer staining. In WT mice, tumor growth delay was achieved by cisplatin (Cis), and this effect was improved in combination with α-GC, but α-GC alone had little effect. Cancer cell proliferation during chemotherapy was significantly inhibited by α-GC, while cancer cell death was significantly upregulated. α-GC following chemotherapy resulted in NKT cell expansion and an increase of interferon-γ production in the draining lymph node, blood and spleen. Gene expression of immune-associated cytokines was upregulated. Strikingly, the percentage of inducible T cell co-stimulator(+)CD4 T cells, Th17/Tc17 cells increased in splenocytes. In CD1d KO mice, however, Cis alone was less effective and Cis + α-GC provided no additional benefit over Cis alone. α-GC alone had minimal effect in both mice. NKT activation between cycles of chemotherapy could improve the outcome of mesothelioma treatment. PMID:25183171

  14. Lipid and Carbohydrate Modifications of α-Galactosylceramide Differently Influence Mouse and Human Type I Natural Killer T Cell Activation*

    PubMed Central

    Birkholz, Alysia; Nemčovič, Marek; Yu, Esther Dawen; Girardi, Enrico; Wang, Jing; Khurana, Archana; Pauwels, Nora; Farber, Elisa; Chitale, Sampada; Franck, Richard W.; Tsuji, Moriya; Howell, Amy; Van Calenbergh, Serge; Kronenberg, Mitchell; Zajonc, Dirk M.

    2015-01-01

    The ability of different glycosphingolipids (GSLs) to activate type I natural killer T cells (NKT cells) has been known for 2 decades. The possible therapeutic use of these GSLs has been studied in many ways; however, studies are needed in which the efficacy of promising GSLs is compared under identical conditions. Here, we compare five unique GSLs structurally derived from α-galactosylceramide. We employed biophysical and biological assays, as well as x-ray crystallography to study the impact of the chemical modifications of the antigen on type I NKT cell activation. Although all glycolipids are bound by the T cell receptor of type I NKT cells in real time binding assays with high affinity, only a few activate type I NKT cells in in vivo or in vitro experiments. The differences in biological responses are likely a result of different pharmacokinetic properties of each lipid, which carry modifications at different parts of the molecule. Our results indicate a need to perform a variety of assays to ascertain the therapeutic potential of type I NKT cell GSL activators. PMID:26018083

  15. Lipid and Carbohydrate Modifications of α-Galactosylceramide Differently Influence Mouse and Human Type I Natural Killer T Cell Activation.

    PubMed

    Birkholz, Alysia; Nemčovič, Marek; Yu, Esther Dawen; Girardi, Enrico; Wang, Jing; Khurana, Archana; Pauwels, Nora; Farber, Elisa; Chitale, Sampada; Franck, Richard W; Tsuji, Moriya; Howell, Amy; Van Calenbergh, Serge; Kronenberg, Mitchell; Zajonc, Dirk M

    2015-07-10

    The ability of different glycosphingolipids (GSLs) to activate type I natural killer T cells (NKT cells) has been known for 2 decades. The possible therapeutic use of these GSLs has been studied in many ways; however, studies are needed in which the efficacy of promising GSLs is compared under identical conditions. Here, we compare five unique GSLs structurally derived from α-galactosylceramide. We employed biophysical and biological assays, as well as x-ray crystallography to study the impact of the chemical modifications of the antigen on type I NKT cell activation. Although all glycolipids are bound by the T cell receptor of type I NKT cells in real time binding assays with high affinity, only a few activate type I NKT cells in in vivo or in vitro experiments. The differences in biological responses are likely a result of different pharmacokinetic properties of each lipid, which carry modifications at different parts of the molecule. Our results indicate a need to perform a variety of assays to ascertain the therapeutic potential of type I NKT cell GSL activators. PMID:26018083

  16. Nasal NK/T cell lymphoma presents with long-term nasal blockage and fever: a rare case report and literature review

    PubMed Central

    Zou, Hai; Pan, Ke-Hua; Wu, Liang; Pan, Hong-Ying; Ding, Ya-Hui; Zheng, Ming-Hua

    2016-01-01

    NK/T cell lymphoma (NKTCL) is a common disease which is a threat to human health. Nasal NKTCL is a rare but serious type of systemic lymphoma because of its high mortality rate and serious complications. In this case report, we describe a male who presented with nasal blockage in the right side, a fever of one month duration and a soy-like, painless and gradually increasing mass in the right submandibular region due to nasal NKTCL. The patient had no significant medical history and the initial clinical symptoms were nasal blockage. Contrast computed tomography showed that the nasopharyngeal mucosa was thickened and that the celiac and retroperitoneal lymphaden was intumescent. Finally a biopsy, guided by nasal endoscopy and examined using flow cytometry confirmed a diagnosis of NKTCL. Nasal NKTCL is rare and has no unique characteristics at first presentation, such as epidemiology and obvious clinical manifestation. As no effective therapy is currently available for this disease, early diagnosis and therapy of nasal NKTCL remains challenging. PMID:26885897

  17. Concurrent chemoradiotherapy followed by L-asparaginase-containing chemotherapy, VIDL, for localized nasal extranodal NK/T cell lymphoma: CISL08-01 phase II study.

    PubMed

    Kim, Seok Jin; Yang, Deok-Hwan; Kim, Jin Seok; Kwak, Jae-Yong; Eom, Hyeon-Seok; Hong, Dae Sik; Won, Jong Ho; Lee, Jae Hoon; Yoon, Dok Hyun; Cho, Jaeho; Nam, Taek-Keun; Lee, Sang-Wook; Ahn, Yong Chan; Suh, Cheolwon; Kim, Won Seog

    2014-11-01

    We conducted a phase II trial of concurrent chemoradiotherapy (CCRT) followed by 2 cycles of L-asparaginase-containing chemotherapy for patients who were newly diagnosed with stages IE and IIE nasal extranodal NK/T cell lymphoma (ENKTL). CCRT consisted of 40-44 Gy of radiotherapy with weekly administration of 30 mg/m(2) of cisplatin for 4 weeks. Two cycles of VIDL (etoposide (100 mg/m(2)), ifosfamide (1,200 mg/m(2)), and dexamethasone (40 mg) from days 1 to 3, and L-asparaginase (4,000 IU/m(2)) every other day from days 8 to 20) were administered sequentially. CCRT yielded a 90 % overall response rate without significant side effects in 30 patients, including 20 patients with complete response (CR); however, two patients showed distant disease progression. After CCRT, VIDL chemotherapy showed an 87 % final CR rate (26/30). Although grade III or IV hematologic toxicity was frequent during VIDL chemotherapy, no treatment-related mortality was observed, and L-asparaginase-associated toxicity was manageable. With a median follow-up of 44 months, 11 patients showed local (n = 4) and distant (n = 7) relapse or progression. The estimated 5-year progression-free and overall survival rates were 73 and 60 %, respectively. In conclusion, CCRT followed by L-asparaginase-containing chemotherapy is a feasible treatment for newly diagnosed stages IE/IIE nasal ENKTL. PMID:24947798

  18. Local Production of Interferon Gamma by Invariant Natural Killer T cells Modulates Acute Lyme Carditis

    PubMed Central

    Olson, Chris M.; Bates, Tonya C.; Izadi, Hooman; Radolf, Justin D.; Huber, Sally A.; Boyson, Jonathan E.; Anguita, Juan

    2009-01-01

    The Lyme disease spirochete, Borrelia burgdorferi, is the only known human pathogen that directly activates invariant natural killer T (iNKT) cells. The number and activation kinetics of iNKT cells vary greatly among different strains of mice. We now report the role of the iNKT cell response in the pathogenesis of Lyme disease using C57Bl/6 mice, a strain with optimal iNKT cell activation that is resistant to the development of spirochetal-induced inflammation. During experimental infection of B6 mice with B. burgdorferi, iNKT cells localize to the inflamed heart where they are activated by CD1d-expressing macrophages. Activation of iNKT cells in vivo results in the production of IFNγ, which we demonstrate ameliorates the severity of murine Lyme carditis by at least two mechanisms. First, IFNγ enhances the recognition of B. burgdorferi by macrophages, leading to increased phagocytosis of the spirochete. Secondly, IFNγ activation of macrophages increases the surface expression of CD1d, thereby facilitating further iNKT activation. Collectively, our data demonstrate that in the resistant background, B6, iNKT cells modulate the severity of murine Lyme carditis through the action of IFNγ, which appears to self-renew through a positive feedback loop during infection. PMID:19265151

  19. CRISPR-Mediated Slamf1Δ/Δ Slamf5Δ/Δ Slamf6Δ/Δ Triple Gene Disruption Reveals NKT Cell Defects but Not T Follicular Helper Cell Defects

    PubMed Central

    Hu, Joyce K.; Crampton, Jordan C.; Locci, Michela; Crotty, Shane

    2016-01-01

    SAP (SH2D1A) is required intrinsically in CD4 T cells to generate germinal center responses and long-term humoral immunity. SAP binds to SLAM family receptors, including SLAM, CD84, and Ly108 to enhance cytokine secretion and sustained T cell:B cell adhesion, which both improve T follicular helper (Tfh) cell aid to germinal center (GC) B cells. To understand the overlapping roles of multiple SLAM family receptors in germinal center responses, Slamf1Δ/Δ Slamf5Δ/Δ Slamf6Δ/Δ triple gene disruption (Slamf1,5,6Δ/Δ) mice were generated using CRISPR-Cas9 gene editing to eliminate expression of SLAM (CD150), CD84, and Ly108, respectively. Gene targeting was highly efficient, with 6 of 6 alleles disrupted in 14 of 23 pups and the majority of alleles disrupted in the remaining pups. NKT cell differentiation in Slamf1,5,6Δ/Δ mice was defective, but not completely absent. The remaining NKT cells exhibited substantially increased 2B4 (SLAMF4) expression. Surprisingly, there were no overt defects in germinal center responses to acute viral infections or protein immunizations in Slamf1,5,6Δ/Δ mice, unlike Sh2d1a-/- mice. Similarly, in the context of a competitive environment, SLAM family receptor expressing GC Tfh cell, GC B cell, and plasma cell responses exhibited no advantages over Slamf1,5,6Δ/Δ cells. PMID:27223891

  20. Autoreactive natural killer T cells: promoting immune protection and immune tolerance through varied interactions with myeloid antigen-presenting cells

    PubMed Central

    Hegde, Subramanya; Fox, Lisa; Wang, Xiaohua; Gumperz, Jenny E

    2010-01-01

    Natural killer T (NKT) cells are innate T lymphocytes that are restricted by CD1d antigen-presenting molecules and recognize lipids and glycolipids as antigens. NKT cells have attracted attention for their potent immunoregulatory effects. Like other types of regulatory lymphocytes, a high proportion of NKT cells appear to be autoreactive to self antigens. Thus, as myeloid antigen-presenting cells (APCs) such as monocytes, dendritic cells (DCs) and myeloid-derived suppressor cells (MDSCs) constitutively express CD1d, NKT cells are able to interact with these APCs not only during times of immune activation but also in immunologically quiescent periods. The interactions of NKT cells with myeloid APCs can have either pro-inflammatory or tolerizing outcomes, and a central question is how the ensuing response is determined. Here we bring together published results from a variety of model systems to highlight three critical factors that influence the outcome of the NKT–APC interaction: (i) the strength of the antigenic signal delivered to the NKT cell, as determined by antigen abundance and/or T-cell receptor (TCR) affinity; (ii) the presence or absence of cytokines that costimulate NKT cells [e.g. interleukin (IL)-12, IL-18 and interferon (IFN)-α]; (iii) APC intrinsic factors such as differentiation state (e.g. monocyte versus DC) and Toll-like receptor (TLR) stimulation. Together with recent findings that demonstrate new links between NKT cell activation and endogenous lipid metabolism, these results outline a picture in which the functions of NKT cells are closely attuned to the existing biological context. Thus, NKT cells may actively promote tolerance until a critical level of danger signals arises, at which point they switch to activating pro-inflammatory immune responses. PMID:20465577

  1. Neutrophilic granulocytes modulate invariant natural killer T cell function in mice and humans

    PubMed Central

    Wingender, Gerhard; Hiss, Marcus; Engel, Isaac; Peukert, Konrad; Ley, Klaus; Haller, Hermann; Kronenberg, Mitchell; von Vietinghoff, Sibylle

    2012-01-01

    Invariant natural killer T (iNKT) cells are a conserved αβTCR+ T cell population that can swiftly produce large amounts of cytokines, thereby activating other leukocytes, including neutrophilic granulocytes (neutrophils). Here we investigated the reverse relationship, showing that high neutrophil concentrations suppress the iNKT cell response in mice and humans. Peripheral Vα14i NKT cells from spontaneously neutrophilic mice produced reduced cytokines in response to the model iNKT cell antigen αGalCer and expressed lower amounts of the T-bet and GATA3 transcription factors than did wild-type controls. This influence was extrinsic, as iNKT cell transcription factor expression in mixed chimeric mice depended on neutrophil count, not iNKT cell genotype. Transcription factor expression was also decreased in primary iNKT cells from the neutrophil rich bone marrow compared to spleen in wild-type mice. In vitro, the function of both mouse and human iNKT cells was inhibited by co-incubation with neutrophils. This required cell-cell contact with live neutrophils. Neutrophilic inflammation in experimental peritonitis in mice decreasediNKT cell T-bet and GATA3 expression and αGalCer induced cytokine production in vivo. This was reverted by blockade of neutrophil mobilization. Similarly, iNKT cells from the human peritoneal cavity expressed lower transcription factor levels during neutrophilic peritonitis. Our data reveal a novel regulatory axis whereby neutrophils reduce iNKT cell responses, which may be important in shaping the extent of inflammation. PMID:22387552

  2. An Optimized Method for Isolating and Expanding Invariant Natural Killer T Cells from Mouse Spleen.

    PubMed

    Govindarajan, Srinath; Elewaut, Dirk; Drennan, Michael

    2015-01-01

    The ability to rapidly secrete cytokines upon stimulation is a functional characteristic of the invariant natural killer T (iNKT) cell lineage. iNKT cells are therefore characterized as an innate T cell population capable of activating and steering adaptive immune responses. The development of improved techniques for the culture and expansion of murine iNKT cells facilitates the study of iNKT cell biology in in vitro and in vivo model systems. Here we describe an optimized procedure for the isolation and expansion of murine splenic iNKT cells. Spleens from C57Bl/6 mice are removed, dissected and strained and the resulting cellular suspension is layered over density gradient media. Following centrifugation, splenic mononuclear cells (MNCs) are collected and CD5-positive (CD5(+)) lymphocytes are enriched for using magnetic beads. iNKT cells within the CD5(+) fraction are subsequently stained with αGalCer-loaded CD1d tetramer and purified by fluorescence activated cell sorting (FACS). FACS sorted iNKT cells are then initially cultured in vitro using a combination of recombinant murine cytokines and plate-bound T cell receptor (TCR) stimuli before being expanded in the presence of murine recombinant IL-7. Using this technique, approximately 10(8) iNKT cells can be generated within 18-20 days of culture, after which they can be used for functional assays in vitro, or for in vivo transfer experiments in mice. PMID:26555769

  3. A Detrimental Role for Invariant Natural Killer T Cells in the Pathogenesis of Experimental Dengue Virus Infection

    PubMed Central

    Renneson, Joelle; Guabiraba, Rodrigo; Maillet, Isabelle; Marques, Rafael E.; Ivanov, Stoyan; Fontaine, Josette; Paget, Christophe; Quesniaux, Valérie; Faveeuw, Christelle; Ryffel, Bernhard; Teixeira, Mauro M.; Trottein, François

    2011-01-01

    Dengue virus (DENV), a member of the mosquito-borne flaviviruses, is a serious public health problem in many tropical countries. We assessed the in vivo physiologic contribution of invariant natural killer T (iNKT) cells, a population of nonconventional lipid-reactive αβ T lymphocytes, to the host response during experimental DENV infection. We used a mouse-adapted DENV serotype 2 strain that causes a disease that resembles severe dengue in humans. On DENV challenge, splenic and hepatic iNKT cells became activated insofar as CD69 and Fas ligand up-regulation and interferon-γ production. C57BL/6 mice deficient in iNKT cells (Jα18−/−) were more resistant to lethal infection than were wild-type animals, and the phenotype was reversed by adoptive transfer of iNKT cells to Jα18−/− animals. The absence of iNKT cells in Jα18−/− mice was associated with decreased systemic and local inflammatory responses, less liver injury, diminished vascular leak syndrome, and reduced activation of natural killer cells and neutrophils. iNKT cell functions were not necessary for control of primary DENV infection, after either natural endogenous activation or exogenous activation with the canonical iNKT cell agonist α-galactosylceramide. Together, these data reveal a novel and critical role for iNKT cells in the pathogenesis of severe experimental dengue disease. PMID:21843496

  4. Lipid and glycolipid antigens of CD1d-restricted natural killer T cells

    PubMed Central

    Venkataswamy, Manjunatha M.; Porcelli, Steven A.

    2009-01-01

    In spite of their relatively limited antigen receptor repertoire, CD1d-restricted NKT cells recognize a surprisingly diverse range of lipid and glycolipid antigens. Recent studies of natural and synthetic CD1d presented antigens provide an increasingly detailed picture of how the specific structural features of these lipids and glycolipids influence their ability to be presented to NKT cells and stimulate their diverse immunologic functions. Particularly for synthetic analogues of α-galactosylceramides which have been the focus of intense recent investigation, it is becoming clear that the design of glycolipid antigens with the ability to precisely control the specific immunologic activities of NKT cells is likely to be feasible. The emerging details of the mechanisms underlying the structure-activity relationship of NKT cell antigens will assist greatly in the design and production of immunomodulatory agents for the precise manipulation of NKT cells and the many other components of the immune system that they influence. PMID:19945296

  5. Human Dendritic Cells Derived From Embryonic Stem Cells Stably Modified With CD1d Efficiently Stimulate Antitumor Invariant Natural Killer T Cell Response

    PubMed Central

    2014-01-01

    Invariant natural killer T (iNKT) cells are a unique lymphocyte subpopulation that mediates antitumor activities upon activation. A current strategy to harness iNKT cells for cancer treatment is endogenous iNKT cell activation using patient-derived dendritic cells (DCs). However, the limited number and functional defects of patient DCs are still the major challenges for this therapeutic approach. In this study, we investigated whether human embryonic stem cells (hESCs) with an ectopically expressed CD1d gene could be exploited to address this issue. Using a lentivector carrying an optimized expression cassette, we generated stably modified hESC lines that consistently overexpressed CD1d. These modified hESC lines were able to differentiate into DCs as efficiently as the parental line. Most importantly, more than 50% of such derived DCs were CD1d+. These CD1d-overexpressing DCs were more efficient in inducing iNKT cell response than those without modification, and their ability was comparable to that of DCs generated from monocytes of healthy donors. The iNKT cells expanded by the CD1d-overexpressing DCs were functional, as demonstrated by their ability to lyse iNKT cell-sensitive glioma cells. Therefore, hESCs stably modified with the CD1d gene may serve as a convenient, unlimited, and competent DC source for iNKT cell-based cancer immunotherapy. PMID:24292792

  6. Natural Killer T Cells Activated by a Lipopeptidophosphoglycan from Entamoeba histolytica Are Critically Important To Control Amebic Liver Abscess

    PubMed Central

    Lindner, Buko; Winau, Florian; Isibasi, Armando; Moreno-Lafont, Martha; Ulmer, Artur J.; Holst, Otto; Tannich, Egbert; Jacobs, Thomas

    2009-01-01

    The innate immune response is supposed to play an essential role in the control of amebic liver abscess (ALA), a severe form of invasive amoebiasis due to infection with the protozoan parasite Entamoeba histolytica. In a mouse model for the disease, we previously demonstrated that Jα18-/- mice, lacking invariant natural killer T (iNKT) cells, suffer from more severe abscess development. Here we show that the specific activation of iNKT cells using α-galactosylceramide (α-GalCer) induces a significant reduction in the sizes of ALA lesions, whereas CD1d−/− mice develop more severe abscesses. We identified a lipopeptidophosphoglycan from E. histolytica membranes (EhLPPG) as a possible natural NKT cell ligand and show that the purified phosphoinositol (PI) moiety of this molecule induces protective IFN-γ but not IL-4 production in NKT cells. The main component of EhLPPG responsible for NKT cell activation is a diacylated PI, (1-O-[(28∶0)-lyso-glycero-3-phosphatidyl-]2-O-(C16:0)-Ins). IFN-γ production by NKT cells requires the presence of CD1d and simultaneously TLR receptor signalling through MyD88 and secretion of IL-12. Similar to α-GalCer application, EhLPPG treatment significantly reduces the severity of ALA in ameba-infected mice. Our results suggest that EhLPPG is an amebic molecule that is important for the limitation of ALA development and may explain why the majority of E. histolytica-infected individuals do not develop amebic liver abscess. PMID:19436711

  7. Natural killer T cells activated by a lipopeptidophosphoglycan from Entamoeba histolytica are critically important to control amebic liver abscess.

    PubMed

    Lotter, Hannelore; González-Roldán, Nestor; Lindner, Buko; Winau, Florian; Isibasi, Armando; Moreno-Lafont, Martha; Ulmer, Artur J; Holst, Otto; Tannich, Egbert; Jacobs, Thomas

    2009-05-01

    The innate immune response is supposed to play an essential role in the control of amebic liver abscess (ALA), a severe form of invasive amoebiasis due to infection with the protozoan parasite Entamoeba histolytica. In a mouse model for the disease, we previously demonstrated that Jalpha18(-/-) mice, lacking invariant natural killer T (iNKT) cells, suffer from more severe abscess development. Here we show that the specific activation of iNKT cells using alpha-galactosylceramide (alpha-GalCer) induces a significant reduction in the sizes of ALA lesions, whereas CD1d(-/-) mice develop more severe abscesses. We identified a lipopeptidophosphoglycan from E. histolytica membranes (EhLPPG) as a possible natural NKT cell ligand and show that the purified phosphoinositol (PI) moiety of this molecule induces protective IFN-gamma but not IL-4 production in NKT cells. The main component of EhLPPG responsible for NKT cell activation is a diacylated PI, (1-O-[(28:0)-lyso-glycero-3-phosphatidyl-]2-O-(C16:0)-Ins). IFN-gamma production by NKT cells requires the presence of CD1d and simultaneously TLR receptor signalling through MyD88 and secretion of IL-12. Similar to alpha-GalCer application, EhLPPG treatment significantly reduces the severity of ALA in ameba-infected mice. Our results suggest that EhLPPG is an amebic molecule that is important for the limitation of ALA development and may explain why the majority of E. histolytica-infected individuals do not develop amebic liver abscess. PMID:19436711

  8. Mutation of the Traj18 gene segment using TALENs to generate Natural Killer T cell deficient mice.

    PubMed

    Zhang, Jingjing; Bedel, Romain; Krovi, S Harsha; Tuttle, Kathryn D; Zhang, Bicheng; Gross, James; Gapin, Laurent; Matsuda, Jennifer L

    2016-01-01

    Invariant Natural Killer T (iNKT) cells are a unique subset of T lymphocytes that have been implicated in both promoting and suppressing a multitude of immune responses. In mice, iNKT cells express T cell antigen receptors (TCRs) comprising a unique TCRα rearrangement between the Trav11 and Traj18 gene segments. When paired with certain Trbv TCRβ chains, these TCRs recognize lipid antigens presented by the major histocompatibility complex (MHC) class I-like molecule, CD1d. Until recently, the sole model of iNKT deficiency targeted the Jα18, which is absolutely required to form the TCR with the appropriate antigenic specificity. However, these mice were demonstrated to have a large reduction in TCR repertoire diversity, which could confound results arising from studies using these mice. Here, we have created a new NKT-deficient mouse strain using transcription activator-like effector nuclease (TALEN) technology to only disrupt the expression of Jα18, leaving the remaining Jα repertoire unperturbed. We confirm that these mice lack iNKT cells and do not respond to lipid antigen stimulation while the development of conventional T cells, regulatory T cells, and type Ib NKT cells is normal. This new mouse strain will serve as a new model of iNKT cell deficiency to facilitate our understanding of iNKT biology. PMID:27256918

  9. Mutation of the Traj18 gene segment using TALENs to generate Natural Killer T cell deficient mice

    PubMed Central

    Zhang, Jingjing; Bedel, Romain; Krovi, S. Harsha; Tuttle, Kathryn D.; Zhang, Bicheng; Gross, James; Gapin, Laurent; Matsuda, Jennifer L.

    2016-01-01

    Invariant Natural Killer T (iNKT) cells are a unique subset of T lymphocytes that have been implicated in both promoting and suppressing a multitude of immune responses. In mice, iNKT cells express T cell antigen receptors (TCRs) comprising a unique TCRα rearrangement between the Trav11 and Traj18 gene segments. When paired with certain Trbv TCRβ chains, these TCRs recognize lipid antigens presented by the major histocompatibility complex (MHC) class I-like molecule, CD1d. Until recently, the sole model of iNKT deficiency targeted the Jα18, which is absolutely required to form the TCR with the appropriate antigenic specificity. However, these mice were demonstrated to have a large reduction in TCR repertoire diversity, which could confound results arising from studies using these mice. Here, we have created a new NKT-deficient mouse strain using transcription activator-like effector nuclease (TALEN) technology to only disrupt the expression of Jα18, leaving the remaining Jα repertoire unperturbed. We confirm that these mice lack iNKT cells and do not respond to lipid antigen stimulation while the development of conventional T cells, regulatory T cells, and type Ib NKT cells is normal. This new mouse strain will serve as a new model of iNKT cell deficiency to facilitate our understanding of iNKT biology. PMID:27256918

  10. [Nasal NK/T lymphoma. A case report].

    PubMed

    Ladeb, Saloua; Gaulard, Philippe; Ben Othmen, Tarek; Abd Alsamad, Issam; Delfau-Larue, Marie Hélène; Abdelkefi, Abderrahmen; Torjmen, Lamia; Ben Abdeladhim, Abdeladhim

    2003-04-01

    We report a case of nasal NK/T lymphoma occurring in a 42 year old man, after a 2 year history of nasal obstruction initially related to chronic sinusitis. A first superficial biopsy was not contributive. Twenty months later, a second nasal biopsy led to the diagnosis of nasal NK/T cell lymphoma in view of the presence of a pleomorphic lymphoid infiltrate associated with necrosis and angiocentric features. Extensive immunohistochemical studies performed on paraffin and frozen sections together with genotypic analysis supported the NK cell origin of the neoplastic cells. In addition, EBV infection was established by in situ hybridization which showed EBERs transcripts in the nuclei of virtually all neoplastic cells. The tumour rapidly progressed and the patient died six months after diagnosis. PMID:12843969

  11. Antitumor Responses of Invariant Natural Killer T Cells

    PubMed Central

    Altman, Jennie B.; Benavides, Adriana D.; Das, Rupali; Bassiri, Hamid

    2015-01-01

    Natural killer T (NKT) cells are innate-like lymphocytes that were first described in the late 1980s. Since their initial description, numerous studies have collectively shed light on their development and effector function. These studies have highlighted the unique requirements for the activation of these lymphocytes and the functional responses that distinguish these cells from other effector lymphocyte populations such as conventional T cells and NK cells. This body of literature suggests that NKT cells play diverse nonredundant roles in a number of disease processes, including the initiation and propagation of airway hyperreactivity, protection against a variety of pathogens, development of autoimmunity, and mediation of allograft responses. In this review, however, we focus on the role of a specific lineage of NKT cells in antitumor immunity. Specifically, we describe the development of invariant NKT (iNKT) cells and the factors that are critical for their acquisition of effector function. Next, we delineate the mechanisms by which iNKT cells influence and modulate the activity of other immune cells to directly or indirectly affect tumor growth. Finally, we review the successes and failures of clinical trials employing iNKT cell-based immunotherapies and explore the future prospects for the use of such strategies. PMID:26543874

  12. Antigen specificity of invariant natural killer T-cells.

    PubMed

    Birkholz, Alysia M; Kronenberg, Mitchell

    2015-12-01

    Natural killer T-cells, with an invariant T-cell antigen receptor α-chain (iNKT cells), are unique and conserved subset of lymphocytes capable of altering the immune system through their rapid and potent cytokine responses. They are reactive to lipid antigens presented by the CD1d molecule, an antigen-presenting molecule that is not highly polymorphic. iNKT cell responses frequently involve mixtures of cytokines that work against each other, and therefore attempts are underway to develop synthetic antigens that elicit only strong interferon-gamma (IFNγ) or only strong interleukin-4 responses but not both. Strong IFNγ responses may correlate with tighter binding to CD1d and prolonged stimulation of iNKT cells, and this may be useful for vaccine adjuvants and for stimulating anti-tumor responses. iNKT cells are self-reactive although the structure of the endogenous antigen is controversial. By contrast, bacterial and fungal lipids that engage the T-cell receptor and activate IFNγ from iNKT cells have been identified from both pathogenic and commensal organisms and the responses are in some cases highly protective from pathogens in mice. It is possible that the expanding knowledge of iNKT cell antigens and iNKT cell activation will provide the basis for therapies for patients suffering from infectious and immune diseases and cancer. PMID:27013447

  13. The Role of Invariant Natural Killer T Cells in Dendritic Cell Licensing, Cross-Priming, and Memory CD8+ T Cell Generation

    PubMed Central

    Gottschalk, Catherine; Mettke, Elisabeth; Kurts, Christian

    2015-01-01

    New vaccination strategies focus on achieving CD8+ T cell (CTL) immunity rather than on induction of protective antibody responses. While the requirement of CD4+ T (Th) cell help in dendritic cell (DC) activation and licensing, and in CTL memory induction has been described in several disease models, CTL responses may occur in a Th cell help-independent manner. Invariant natural killer T cells (iNKT cells) can substitute for Th cell help and license DC as well. iNKT cells produce a broad spectrum of Th1 and Th2 cytokines, thereby inducing a similar set of costimulatory molecules and cytokines in DC. This form of licensing differs from Th cell help by inducing other chemokines, while Th cell-licensed DCs produce CCR5 ligands, iNKT cell-licensed DCs produce CCL17, which attracts CCR4+ CD8+ T cells for subsequent activation. It has recently been shown that iNKT cells do not only enhance immune responses against bacterial pathogens or parasites but also play a role in viral infections. The inclusion of iNKT cell ligands in influenza virus vaccines enhanced memory CTL generation and protective immunity in a mouse model. This review will focus on the role of iNKT cells in the cross-talk with cross-priming DC and memory CD8+ T cell formation. PMID:26284065

  14. Natural Killer T Cells in Adipose Tissue Are Activated in Lean Mice

    PubMed Central

    Kondo, Taisuke; Toyoshima, Yujiro; Ishii, Yoshiyuki; Kyuwa, Shigeru

    2013-01-01

    Adipose tissues are closely connected with the immune system. It has been suggested that metabolic syndromes such as type 2 diabetes, arteriosclerosis and liver steatosis can be attributed to adipose tissue inflammation characterized by macrophage infiltration. To understand a physiological and pathological role of natural killer T (NKT) cells on inflammation in adipose tissue, we characterized a subset of NKT cells in abdominal and subcutaneous adipose tissues in C57BL/6J mice fed normal or high-fat diets. NKT cells comprised a larger portion of lymphocytes in adipose tissues compared with the spleen and peripheral blood, with epididymal adipose tissue having the highest number of NKT cells. Furthermore, some NKT cells in adipose tissues expressed higher levels of CD69 and intracellular interferon-γ, whereas the Vβ repertoires of NKT cells in adipose tissues were similar to other cells. In obese mice fed a high-fat diet, adipose tissue inflammation had little effect on the Vβ repertoire of NKT cells in epididymal adipose tissues. We speculate that the NKT cells in adipose tissues may form an equivalent subset in other tissues and that these subsets are likely to participate in adipose tissue inflammation. Additionally, the high expression level of CD69 and intracellular IFN-γ raises the possibility that NKT cells in adipose tissue may be stimulated by some physiological mechanism. PMID:24172196

  15. Testosterone Increases Susceptibility to Amebic Liver Abscess in Mice and Mediates Inhibition of IFNγ Secretion in Natural Killer T Cells

    PubMed Central

    Lotter, Hannelore; Helk, Elena; Bernin, Hannah; Jacobs, Thomas; Prehn, Cornelia; Adamski, Jerzy; González-Roldán, Nestor; Holst, Otto; Tannich, Egbert

    2013-01-01

    Amebic liver abscess (ALA), a parasitic disease due to infection with the protozoan Entamoeba histolytica, occurs age and gender dependent with strong preferences for adult males. Using a mouse model for ALA with a similar male bias for the disease, we have investigated the role of female and male sexual hormones and provide evidence for a strong contribution of testosterone. Removal of testosterone by orchiectomy significantly reduced sizes of abscesses in male mice, while substitution of testosterone increased development of ALA in female mice. Activation of natural killer T (NKT) cells, which are known to be important for the control of ALA, is influenced by testosterone. Specifically activated NKT cells isolated from female mice produce more IFNγ compared to NKT cells derived from male mice. This high level production of IFNγ in female derived NKT cells was inhibited by testosterone substitution, while the IFNγ production in male derived NKT cells was increased by orchiectomy. Gender dependent differences were not a result of differences in the total number of NKT cells, but a result of a higher activation potential for the CD4− NKT cell subpopulation in female mice. Taken together, we conclude that the hormone status of the host, in particular the testosterone level, determines susceptibility to ALA at least in a mouse model of the disease. PMID:23424637

  16. Testosterone increases susceptibility to amebic liver abscess in mice and mediates inhibition of IFNγ secretion in natural killer T cells.

    PubMed

    Lotter, Hannelore; Helk, Elena; Bernin, Hannah; Jacobs, Thomas; Prehn, Cornelia; Adamski, Jerzy; González-Roldán, Nestor; Holst, Otto; Tannich, Egbert

    2013-01-01

    Amebic liver abscess (ALA), a parasitic disease due to infection with the protozoan Entamoeba histolytica, occurs age and gender dependent with strong preferences for adult males. Using a mouse model for ALA with a similar male bias for the disease, we have investigated the role of female and male sexual hormones and provide evidence for a strong contribution of testosterone. Removal of testosterone by orchiectomy significantly reduced sizes of abscesses in male mice, while substitution of testosterone increased development of ALA in female mice. Activation of natural killer T (NKT) cells, which are known to be important for the control of ALA, is influenced by testosterone. Specifically activated NKT cells isolated from female mice produce more IFNγ compared to NKT cells derived from male mice. This high level production of IFNγ in female derived NKT cells was inhibited by testosterone substitution, while the IFNγ production in male derived NKT cells was increased by orchiectomy. Gender dependent differences were not a result of differences in the total number of NKT cells, but a result of a higher activation potential for the CD4(-) NKT cell subpopulation in female mice. Taken together, we conclude that the hormone status of the host, in particular the testosterone level, determines susceptibility to ALA at least in a mouse model of the disease. PMID:23424637

  17. Nackt (nkt), a new hair loss mutation of the mouse with associated CD4 deficiency.

    PubMed

    Benavides, F; Giordano, M; Fiette, L; Bueno Brunialti, A L; Martin Palenzuela, N; Vanzulli, S; Baldi, P; Schmidt, R; Dosne Pasqualini, C; Guénet, J

    1999-05-01

    A spontaneous recessive mutation named nackt (symbol: nkt) affecting hair growth and T-cell development was discovered in a moderately inbred stock of mice. Skin lesions were characterized by sparse rough coat, bare patches around the eyes and neck, and a scratching behavior throughout life. Fluorescence-activated cell sorter analysis indicated a deficiency in the CD4(+) 8(-) T-cell subset in the thymus and a marked decrease in CD4(+) T cells in peripheral lymphoid organs. Linkage analysis using a set of molecular markers and an F2 intersubspecific cross indicated that the mutation maps to the central region of mouse chromosome 13, in a region homologous to human chromosome 5q22-q35. PMID:10199917

  18. Natural killer T cells in health and disease

    PubMed Central

    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

  19. Pulmonary natural killer T cells play an essential role in mediating hyperoxic acute lung injury.

    PubMed

    Nowak-Machen, Martina; Schmelzle, Moritz; Hanidziar, Dusan; Junger, Wolfgang; Exley, Mark; Otterbein, Leo; Wu, Yan; Csizmadia, Eva; Doherty, Glen; Sitkovsky, Michail; Robson, Simon C

    2013-05-01

    Critically ill patients are routinely exposed to high concentrations of supplemental oxygen for prolonged periods of time, which can be life-saving in the short term, but such exposure also causes severe lung injury and increases mortality. To address this therapeutic dilemma, we studied the mechanisms of the tissue-damaging effects of oxygen in mice. We show that pulmonary invariant natural killer T (iNKT) cells are unexpectedly crucial in the development of acute oxygen-induced lung injury. iNKT cells express high concentrations of the ectonucleotidase CD39, which regulates their state of activation. Both iNKT cell-deficient (Jα18(-/-)) and CD39-null mice tolerate hyperoxia, compared with wild-type control mice that exhibit severe lung injury. An adoptive transfer of wild-type iNKT cells into Jα18(-/-) mice results in hyperoxic lung injury, whereas the transfer of CD39-null iNKT cells does not. Pulmonary iNKT cell activation and proliferation are modulated by ATP-dependent purinergic signaling responses. Hyperoxic lung injury can be induced by selective P2X7-receptor blockade in CD39-null mice. Our data indicate that iNKT cells are involved in the pathogenesis of hyperoxic lung injury, and that tissue protection can be mediated through ATP-induced P2X7 receptor signaling, resulting in iNKT cell death. In conclusion, our data suggest that iNKT cells and purinergic signaling should be evaluated as potential novel therapeutic targets to prevent hyperoxic lung injury. PMID:23349052

  20. Activation of Nonclassical CD1d-Restricted NK T Cells Induces Airway Hyperreactivity in β2-Microglobulin-Deficient Mice1

    PubMed Central

    Meyer, Everett H.; Pichavant, Muriel; Akbari, Omid; Yasumi, Takahiro; Savage, Paul B.; DeKruyff, Rosemarie H.; Umetsu, Dale T.

    2016-01-01

    Allergic asthma is characterized by Th2-driven eosinophilic airway inflammation and by a central feature called airway hyperreactivity (AHR), development of which requires the presence of classical type I invariant NK T (iNKT) cells. Allergen-induced AHR, however, develops in β2-microglobulin (β2m)−/− mice, which lack classical iNKT cells, suggesting that in some situations iNKT cells may be dispensable for the development of AHR. In contrast, our studies now suggest that a CD1d-restricted, NK1.1+ noninvariant TCR NKT cell population is present in β2m−/− mice and is responsible for the development of AHR but not for Th2 responses. Furthermore, treatment of β2m−/− mice with anti-CD1d mAb or anti-NK1.1 mAb unexpectedly abolished allergen-induced AHR. The CD1-restricted NKT cells in these mice, which failed to respond to α-galactosylceramide and which therefore were not classical type I iNKT cells, appear to represent an NKT cell subset restricted by a β2m-independent form of CD1d. These results indicate that, although classical type I iNKT cells are normally required for the development of AHR, under different circumstances other NKT cell subsets, including nonclassical NKT cells, may substitute for classical iNKT cells and induce AHR. PMID:18802058

  1. Roles of the programmed cell death 1, T cell immunoglobulin mucin-3, and cluster of differentiation 288 pathways in the low reactivity of invariant natural killer T cells after chronic hepatitis B virus infection.

    PubMed

    Yang, Zhixin; Lei, Yu; Chen, Chunbo; Ren, Hong; Shi, Tongdong

    2015-10-01

    One of the main responses of invariant natural killer T (iNKT) cells to antigen stimulation is the rapid production of interleukin (IL)-4 and interferon (IFN)-γ cytokines. There is a decline in the function of iNKT cells in chronic hepatitis B (CHB) patients. In this study, we explored the impact of programmed cell death 1 (PD-1), T cell immunoglobulin mucin-3 (Tim-3), and cluster of differentiation 28 (CD28) expression on iNKT cell functions in CHB patients. Flow cytometry was used to test iNKT frequencies and levels of PD-1, Tim-3, CD28, IL-4, and IFN-γ secreted by iNKT cells. An enzyme-linked immunosorbent assay (ELISA) was used to measure IL-4 and IFN-γ secretion upon α-galactosylceramide (α-GalCer) activation ex vivo. We found that the levels of expression of PD-1 and Tim-3 from iNKT cells in CHB patients were significantly higher than in healthy donors (p < 0.05), but there was lower expression of CD28 (p < 0.05) and an impaired capability to produce IL-4 and IFN-γ (p < 0.05). In vitro α-GalCer stimulation upregulated the expression of PD-1(+) iNKT cells (p < 0.05), Tim-3(+) iNKT cells (p < 0.05), and CD28(+) iNKT cells (p < 0.05). In response to combination therapies consisting of α-GalCer and anti-PDL1 monoclonal antibody (mAb) and/or anti-Tim-3 mAbs and/or anti-CD80/anti-CD28 mAbs, IL-4(+) and IFN-γ(+) iNKT cells demonstrated different degrees of growth (p < 0.05). The functional decline of iNKT cells was closely related to the decrease in CD28 expression and the increases of Tim-3 and PD-1. In addition, clinical antiviral treatment with lamivudine could partially restore the immune function of iNKT cells in CHB patients. PMID:26215444

  2. Design of natural killer T cell activators: Structure and function of a microbial glycosphingolipid bound to mouse CD1d

    PubMed Central

    Wu, Douglass; Zajonc, Dirk M.; Fujio, Masakazu; Sullivan, Barbara A.; Kinjo, Yuki; Kronenberg, Mitchell; Wilson, Ian A.; Wong, Chi-Huey

    2006-01-01

    Natural killer T (NKT) cells provide an innate-type immune response upon T cell receptor interaction with CD1d-presented antigens. We demonstrate through equilibrium tetramer binding and antigen presentation assays with Vα14i-positive NKT cell hybridomas that the Sphingomonas glycolipid α-galacturonosyl ceramide (GalA-GSL) is a NKT cell agonist that is significantly weaker than α-galactosylceramide (α-GalCer), the most potent known NKT agonist. For GalA-GSL, a shorter fatty acyl chain, an absence of the 4-OH on the sphingosine tail and a 6′-COOH group on the galactose moiety account for its observed antigenic potency. We further determined the crystal structure of mCD1d in complex with GalA-GSL at 1.8-Å resolution. The overall binding mode of GalA-GSL to mCD1d is similar to that of the short-chain α-GalCer ligand PBS-25, but its sphinganine chain is more deeply inserted into the F′ pocket due to alternate hydrogen-bonding interactions between the sphinganine 3-OH with Asp-80. Subsequently, a slight lateral shift (>1 Å) of the galacturonosyl head group is noted at the CD1 surface compared with the galactose of α-GalCer. Because the relatively short C14 fatty acid of GalA-GSL does not fully occupy the A′ pocket, a spacer lipid is found that stabilizes this pocket. The lipid spacer was identified by GC/MS as a mixture of saturated and monounsaturated palmitic acid (C16). Comparison of available crystal structures of α-anomeric glycosphingolipids now sheds light on the structural basis of their differential antigenic potency and has led to the design and synthesis of NKT cell agonists with enhanced cell-based stimulatory activities compared with α-GalCer. PMID:16537470

  3. Retinoic Acid Modulates Interferon-γ Production by Hepatic Natural Killer T Cells via Phosphatase 2A and the Extracellular Signal-Regulated Kinase Pathway

    PubMed Central

    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

  4. Orchestration of Invariant Natural Killer T cell development by E and Id proteins

    PubMed Central

    Roy, Sumedha; Zhuang, Yuan

    2015-01-01

    Natural Killer T (NKT) cells are αβ T cells that express a semi-invariant T cell receptor (TCR) along with Natural Killer (NK) cell markers, and have an innate cell-like ability to produce a myriad of cytokines very quickly upon antigen exposure and subsequent activation. These cells are diverted from conventional single positive (SP) T cell fate at the double positive (DP) stage where TCR-mediated recognition of a lipid antigen presented on a CD1d molecule promotes their selection into the NKT lineage. Although many key regulatory molecules have been shown to play important roles in the development of NKT cells, the mechanism of lineage specification and acquisition of effector functions in these cells still remain to be fully addressed. In this review we specifically discuss the role of a family of class I Helix Loop Helix proteins known as E proteins, and of their antagonists Id proteins in NKT cell development. Recent works have shown that these proteins play key roles in iNKT development, from the invariant TCR rearrangement to terminal differentiation and maturation. Elucidating these roles provides an opportunity to uncover the transcriptional network that separates NKT cells from the concurrently developed conventional αβ T cells. PMID:25746046

  5. Activation of invariant Natural Killer T lymphocytes in response to the α-galactosylceramide analogue KRN7000 encapsulated in PLGA-based nanoparticles and microparticles.

    PubMed

    Macho Fernandez, Elodie; Chang, Jiang; Fontaine, Josette; Bialecki, Emilie; Rodriguez, Fabien; Werkmeister, Elisabeth; Krieger, Vanessa; Ehret, Christophe; Heurtault, Béatrice; Fournel, Sylvie; Frisch, Benoit; Betbeder, Didier; Faveeuw, Christelle; Trottein, François

    2012-02-14

    Invariant Natural Killer T (iNKT) cells have potent immunostimulatory activities that could be exploited for human therapies. The high-affinity CD1d antigen α-galactosylceramide analogue KRN7000 (KRN) activates a cascade of anti-tumor effector cells and clinical studies have already had some initial success. To improve the efficacy of the treatment, strategies that aim to vectorize KRN would be valuable. In this study, we intended to characterize and compare the effect of KRN encapsulated in poly(lactic-co-glycolic acid) (PLGA)-based nanoparticles (NPs, 90nm) and microparticles instead of macroparticles (MPs, 715nm) on the iNKT cell response. Our data show that whatever the size of the particles, vectorized KRN induced potent primary activation of iNKT cells in vitro and in vivo. We show that endocytosis of PLGA-based particles by dendritic cells is mediated by a clathrin-dependent manner and that this event is important to stimulate iNKT cells. Finally, we report that KRN vectorized in NPs and MPs exhibited different behaviours in vivo in terms of iNKT cell expansion and responsiveness to a recall stimulation. Collectively, our data validate the concept that KRN encapsulated in PLGA-based particles can be used as delivery systems to activate iNKT cells in vitro and in vivo. PMID:21575695

  6. Contribution of Invariant Natural Killer T Cells to Skin Wound Healing.

    PubMed

    Tanno, Hiromasa; Kawakami, Kazuyoshi; Ritsu, Masae; Kanno, Emi; Suzuki, Aiko; Kamimatsuno, Rina; Takagi, Naoyuki; Miyasaka, Tomomitsu; Ishii, Keiko; Imai, Yoshimichi; Maruyama, Ryoko; Tachi, Masahiro

    2015-12-01

    In the present study, we determined the contribution of invariant natural killer T (iNKT) cells to the skin wound healing process. In iNKT cell-deficient (Jα18KO) mice lacking iNKT cells, wound closure was significantly delayed compared with wild-type mice. Collagen deposition, expression of α-smooth muscle actin and CD31, and wound breaking strength were significantly attenuated in Jα18KO mice. The adoptive transfer of liver mononuclear cells from wild-type but not from Jα18KO or interferon (IFN)-γ gene-disrupted (IFN-γKO) mice resulted in the reversal of this impaired wound healing in Jα18KO mice. IFN-γ expression was induced in the wounded tissues, which was significantly decreased at 6, 12, and 24 hours, but increased on day 3 after wounding in Jα18KO mice. The main source of the late-phase IFN-γ production in Jα18KO mice were neutrophils rather than NK cells and T cells. Administration of α-galactosylceramide, an activator of iNKT cells, resulted in the acceleration of wound healing on day 3 in wild-type mice. This effect was not observed in IFN-γKO mice. These results indicate that iNKT cells play important roles in wound healing. The iNKT cell-induced IFN-γ production may regulate the wound healing process in the early phase. PMID:26468976

  7. Intravital Imaging – Dynamic Insights into Natural Killer T Cell Biology

    PubMed Central

    Liew, Pei Xiong; Kubes, Paul

    2015-01-01

    Natural killer T (NKT) cells were first recognized more than two decades ago as a separate and distinct lymphocyte lineage that modulates an expansive range of immune responses. As innate immune cells, NKT cells are activated early during inflammation and infection, and can subsequently stimulate or suppress the ensuing immune response. As a result, researchers hope to harness the immunomodulatory properties of NKT cells to treat a variety of diseases. However, many questions still remain unanswered regarding the biology of NKT cells, including how these cells traffic from the thymus to peripheral organs and how they play such contrasting roles in different immune responses and diseases. In this new era of intravital fluorescence microscopy, we are now able to employ this powerful tool to provide quantitative and dynamic insights into NKT cell biology including cellular dynamics, patrolling, and immunoregulatory functions with exquisite resolution. This review will highlight and discuss recent studies that use intravital imaging to understand the spectrum of NKT cell behavior in a variety of animal models. PMID:26042123

  8. Effect of invariant natural killer T cells with IL-5 and activated IL-6 receptor in ventilator-associated lung injury in mice.

    PubMed

    Shiga, Yuka; Sugamata, Ryuichi; Iwamura, Chiaki; Nagao, Tomokazu; Zao, Jun; Kawakami, Kazuyoshi; Kawachi, Shoji; Nakayama, Toshinori; Suzuki, Kazuo

    2014-02-01

    Mechanical ventilation (MV) is well known to potentially cause ventilator-associated lung injury (VALI). It has also been reported recently that activation of invariant natural killer T (iNKT) cells is involved in the onset/progression of airway inflammation. We analyzed the roles of inflammatory cells, including iNKT cells, and cytokines/chemokines in a mouse model of VALI. C57BL/6 and Vα14(+)NKT cell-deficient (Jα18KO) female mice were subjected to MV for 5 hours. The MV induced lung injury in the mice, with severe histological abnormalities, elevation in the percentages of neutrophils in the bronchoalveolar lavage fluid (BALF), and increase in the number of iNKT cells in the lung. Jα18KO mice subjected to MV for 5 hours also showed lung injury, with decrease of the PaO2/FiO2 ratio (P/F ratio) and elevation of the levels of total protein, IL-5, IL-6, IL-12p40, and keratinocyte-derived cytokine (KC) in the BALF. Intranasal administration of anti-IL-5 monoclonal antibody (mAb) or anti-IL-6 receptor (IL-6R) mAb into the Jα18KO mice prior to the start of MV resulted in significant improvement in the blood oxygenation. In addition, the anti-IL-5 mAb administration was associated with a decrease in the levels of IL-5, IL-9, and IL-6R in the BALF, and anti-IL-6R mAb administration suppressed the mRNA expressions of IL-5, IL-6, IL-6R, and KC. These results suggest that iNKT cells may play a role in attenuating the inflammatory caused by ventilation through IL-5 and IL-6R. PMID:24246030

  9. Invariant natural killer T-cell neutralization is a possible novel therapy for human eosinophilic esophagitis

    PubMed Central

    Rayapudi, Madhavi; Rajavelu, Priya; Zhu, Xiang; Kaul, Ajay; Niranjan, Rituraj; Dynda, Scott; Mishra, Akanksha; Mattner, Jochen; Zaidi, Asifa; Dutt, Parmesh; Mishra, Anil

    2014-01-01

    Eosinophilic esophagitis (EoE) is a recently recognized inflammatory disorder that needs a potential therapeutic strategy. We earlier showed that iNKT cell-deficient mice are protected from allergen-induced EoE. Therefore, we now tested the hypothesis that iNKT cells are induced in the human EoE and is a novel possible target for the treatment of human EoE. Accordingly, we examine number of iNKT cells and eosinophils and expression of iNKT-associated cell surface receptors and chemokines by performing immunofluorescence, qPCR and ELISA in the esophageal biopsies and blood samples of normal subjects (comparison control) and EoE patients. Herein, we show that iNKT cell number, their receptor subcomponents Vα24 and Vβ11 expression, and associated chemokine CXCL16 levels (or expression) are induced significantly in EoE patients compared with normal individuals. In addition, we show that CXCL16 levels (or expression) correlate with the mRNA levels of Vα24 receptor but not well with esophageal eosinophilia in human EoE. Of note, we show that in vivo activation of iNKT cells is sufficient to induce EoE in mice. Furthermore, we show that anti-mCD1d- and anti-hVα24Jα18-neutralizing antibody treatment protects allergen-induced experimental EoE. Taken together, we have shown first time that iNKT cells have a critical pathogenic role in human and experimental EoE. iNKT cell neutralization by humanized anti-CD1d and anti-Vα24Jα18 antibodies might be a novel and potential therapy for human EoE. PMID:25505954

  10. Esophageal involvement by extranodal natural killer T cell lymphoma, nasal type, mimicking Ebstein Barr viral esophagitis in a tonsillar lymphoma patient undergoing chemoradiation therapy.

    PubMed

    Lee, Se Ryeon; Park, Eun Kyung; Won, Nam Hee; Kim, Byung Soo

    2010-09-01

    Esophageal involvement by extranodal natural killer (NK)/T cell lymphoma, nasal type, is rare. As a result, esophageal symptoms in these patients might at first be thought to originate from a benign condition, such as viral esophagitis. It is important to note, however, that benign conditions may mask esophageal involvement by lymphoma. Until now, there has been no report documenting esophageal involvement by lymphoma mimicking viral esophagitis in an extranodal NK/T cell lymphoma patient undergoing active treatment. Here, we report a case of esophageal involvement by extranodal NK/T cell lymphoma, nasal type, initially misdiagnosed as Ebstein Barr virus esophagitis. Lymphoma invasion of the esophagus should be considered if esophageal symptoms do not respond to usual medical esophagitis therapy in an extranodal NK/T cell lymphoma, nasal type, patient undergoing chemoradiation. PMID:20887494

  11. S100A9 and ORM1 serve as predictors of therapeutic response and prognostic factors in advanced extranodal NK/T cell lymphoma patients treated with pegaspargase/gemcitabine

    PubMed Central

    Zhou, Zhiyuan; Li, Zhaoming; Sun, Zhenchang; Zhang, Xudong; Lu, Lisha; Wang, Yingjun; Zhang, Mingzhi

    2016-01-01

    Pegaspargase combined with gemcitabine have greatly improved the outcomes of advanced extranodal NK/T cell lymphoma (ENKL). However, patients frequently undergo recurrent disease due to chemoresistance, and few predictive parameters are available. The present study explored potential biomarkers to predict the therapeutic response of advanced ENKL treated with pegaspargase/gemcitabine and evaluate the prognostic significance. Through serum proteomic analysis, we identified 61 upregulated and 22 downregulated proteins in nonresponders compared with responders. We further validated that patients with unfavourable treatment outcomes displayed higher levels of S100A9 and ORM1 via enzyme-linked immunosorbent assay (ELISA). Moreover, the sensitivity and specificity for detecting refractory patients were 81.5% and 71.4% for S100A9 > 62.0 ng/ml, 85.2% and 77.1% for ORM1 > 1436 ug/ml, 100% and 57.1% for S100A9 combined with ORM1. Furthermore, in multivariate analysis elevated levels of S100A9 were associated with poor 2-year OS (40.2% vs. 76.6%, RR = 2.92, p = 0.005) and 2-year PFS (33.1% vs. 61.1%, RR = 2.61 p = 0.011). High ORM1 also predicted inferior 2-year OS (38.7% vs.76.1, RR = 2.46, p = 0.023) and 2-year PFS (18.4% vs. 73.2%, RR = 2.86, p = 0.009). Our results indicated that S100A9 and ORM1 could serve as reliable predictors of therapeutic response and independent prognostic factors of survival in advanced ENKL patients treated with pegaspargase/gemcitabine. PMID:27021626

  12. IVIg immune reconstitution treatment alleviates the state of persistent immune activation and suppressed CD4 T cell counts in CVID.

    PubMed

    Paquin-Proulx, Dominic; Santos, Bianca A N; Carvalho, Karina I; Toledo-Barros, Myrthes; Barreto de Oliveira, Ana Karolina; Kokron, Cristina M; Kalil, Jorge; Moll, Markus; Kallas, Esper G; Sandberg, Johan K

    2013-01-01

    Common variable immunodeficiency (CVID) is characterized by defective B cell function, impaired antibody production, and increased susceptibility to bacterial infections. Here, we addressed the hypothesis that poor antibody-mediated immune control of infections may result in substantial perturbations in the T cell compartment. Newly diagnosed CVID patients were sampled before, and 6-12 months after, initiation of intravenous immunoglobulin (IVIg) therapy. Treatment-naïve CVID patients displayed suppressed CD4 T cell counts and myeloid dendritic cell (mDC) levels, as well as high levels of immune activation in CD8 T cells, CD4 T cells, and invariant natural killer T (iNKT) cells. Expression of co-stimulatory receptors CD80 and CD83 was elevated in mDCs and correlated with T cell activation. Levels of both FoxP3+ T regulatory (Treg) cells and iNKT cells were low, whereas soluble CD14 (sCD14), indicative of monocyte activation, was elevated. Importantly, immune reconstitution treatment with IVIg partially restored the CD4 T cell and mDC compartments. Treatment furthermore reduced the levels of CD8 T cell activation and mDC activation, whereas levels of Treg cells and iNKT cells remained low. Thus, primary deficiency in humoral immunity with impaired control of microbial infections is associated with significant pathological changes in cell-mediated immunity. Furthermore, therapeutic enhancement of humoral immunity with IVIg infusions alleviates several of these defects, indicating a relationship between poor antibody-mediated immune control of infections and the occurrence of abnormalities in the T cell and mDC compartments. These findings help our understanding of the immunopathogenesis of primary immunodeficiency, as well as acquired immunodeficiency caused by HIV-1 infection. PMID:24130688

  13. Recognition of Microbial Glycolipids by Natural Killer T Cells

    PubMed Central

    Zajonc, Dirk M.; Girardi, Enrico

    2015-01-01

    T cells can recognize microbial antigens when presented by dedicated antigen-presenting molecules. While peptides are presented by classical members of the major histocompatibility complex (MHC) family (MHC I and II), lipids, glycolipids, and lipopeptides can be presented by the non-classical MHC member, CD1. The best studied subset of lipid-reactive T cells are type I natural killer T (iNKT) cells that recognize a variety of different antigens when presented by the non-classical MHCI homolog CD1d. iNKT cells have been shown to be important for the protection against various microbial pathogens, including B. burgdorferi, the causative agents of Lyme disease, and S. pneumoniae, which causes pneumococcal meningitis and community-acquired pneumonia. Both pathogens carry microbial glycolipids that can trigger the T cell antigen receptor (TCR), leading to iNKT cell activation. iNKT cells have an evolutionary conserved TCR alpha chain, yet retain the ability to recognize structurally diverse glycolipids. They do so using a conserved recognition mode, in which the TCR enforces a conserved binding orientation on CD1d. TCR binding is accompanied by structural changes within the TCR binding site of CD1d, as well as the glycolipid antigen itself. In addition to direct recognition of microbial antigens, iNKT cells can also be activated by a combination of cytokines (IL-12/IL-18) and TCR stimulation. Many microbes carry TLR antigens, and microbial infections can lead to TLR activation. The subsequent cytokine response in turn lower the threshold of TCR-mediated iNKT cell activation, especially when weak microbial or even self-antigens are presented during the cause of the infection. In summary, iNKT cells can be directly activated through TCR triggering of strong antigens, while cytokines produced by the innate immune response may be necessary for TCR triggering and iNKT cell activation in the presence of weak antigens. Here, we will review the molecular basis of iNKT cell

  14. B-Cell Lymphopoiesis Is Regulated by Cathepsin L

    PubMed Central

    Badano, Maria Noel; Camicia, Gabriela Lorena; Lombardi, Gabriela; Maglioco, Andrea; Cabrera, Gabriel; Costa, Hector; Meiss, Roberto Pablo

    2013-01-01

    Cathepsin L (CTSL) is a ubiquitously expressed lysosomal cysteine peptidase with diverse and highly specific functions. The involvement of CTSL in thymic CD4+ T-cell positive selection has been well documented. Using CTSLnkt/nkt mice that lack CTSL activity, we have previously demonstrated that the absence of CTSL activity affects the homeostasis of the T-cell pool by decreasing CD4+ cell thymic production and increasing CD8+ thymocyte production. Herein we investigated the influence of CTSL activity on the homeostasis of peripheral B-cell populations and bone marrow (BM) B-cell maturation. B-cell numbers were increased in lymph nodes (LN), spleen and blood from CTSLnkt/nkt mice. Increases in splenic B-cell numbers were restricted to transitional T1 and T2 cells and to the marginal zone (MZ) cell subpopulation. No alterations in the proliferative or apoptosis levels were detected in peripheral B-cell populations from CTSLnkt/nkt mice. In the BM, the percentage and the absolute number of pre-pro-B, pro-B, pre-B, immature and mature B cells were not altered. However, in vitro and in vivo experiments showed that BM B-cell production was markedly increased in CTSLnkt/nkt mice. Besides, BM B-cell emigration to the spleen was increased in CTSLnkt/nkt mice. Colony-forming unit pre-B (CFU pre-B) assays in the presence of BM stromal cells (SC) and reciprocal BM chimeras revealed that both BM B-cell precursors and SC would contribute to sustain the increased B-cell hematopoiesis in CTSLnkt/nkt mice. Overall, our data clearly demonstrate that CTSL negatively regulates BM B-cell production and output therefore influencing the homeostasis of peripheral B cells. PMID:23585893

  15. Stimulation of Natural Killer T Cells by Glycolipids

    PubMed Central

    Anderson, Brian L.; Teyton, Luc; Bendelac, Albert; Savage, Paul B.

    2014-01-01

    Natural killer T (NKT) cells are a subset of T cells that recognize glycolipid antigens presented by the CD1d protein. The initial discovery of immunostimulatory glycolipids from a marine sponge and the T cells that respond to the compounds has led to extensive research by chemists and immunologists to understand how glycolipids are recognized, possible responses by NKT cells, and the structural features of glycolipids necessary for stimulatory activity. The presence of this cell type in humans and most mammals suggests that it plays critical roles in antigen recognition and the interface between innate and adaptive immunity. Both endogenous and exogenous natural antigens for NKT cells have been identified, and it is likely that glycolipid antigens remain to be discovered. Multiple series of structurally varied glycolipids have been synthesized and tested for stimulatory activity. The structural features of glycolipids necessary for NKT cell stimulation are moderately well understood, and designed compounds have proven to be much more potent antigens than their natural counterparts. Nevertheless, control over NKT cell responses by designed glycolipids has not been optimized, and further research will be required to fully reveal the therapeutic potential of this cell type. PMID:24352021

  16. Long-term Outcome of Extranodal NK/T Cell Lymphoma Patients Treated With Postremission Therapy Using EBV LMP1 and LMP2a-specific CTLs

    PubMed Central

    Cho, Seok-Goo; Kim, Nayoun; Sohn, Hyun-Jung; Lee, Suk Kyeong; Oh, Sang Taek; Lee, Hyun-Joo; Cho, Hyun-Il; Yim, Hyeon Woo; Jung, Seung Eun; Park, Gyeongsin; Oh, Joo Hyun; Choi, Byung-Ock; Kim, Sung Won; Kim, Soo Whan; Chung, Nak Gyun; Lee, Jong Wook; Hong, Young Seon; Kim, Tai-Gyu

    2015-01-01

    Extranodal NK/T-cell lymphoma (ENKTCL) is associated with latent Epstein-Barr virus (EBV) infection and frequent relapse even after complete response (CR) to intensive chemotherapy and radiotherapy. The expression of EBV proteins in the tumor provides targets for adoptive immunotherapy with antigen-specific cytotoxic T cells (CTL). To evaluate the efficacy and safety of EBV latent membrane protein (LMP)-1 and LMP-2a-specific CTLs (LMP1/2a CTLs) stimulated with LMP1/2a RNA-transferred dendritic cells, we treated 10 ENKTCL patients who showed complete response to induction therapy. Patients who completed and responded to chemotherapy, radiotherapy, and/or high-dose therapy followed by stem cell transplantation (HDT/SCT) were eligible to receive eight doses of 2 × 107 LMP1/2a CTLs/m2. Following infusion, there were no immediate or delayed toxicities. The 4-year overall survival (OS) and progression-free survival (PFS) were 100%, and 90% (95% CI: 71.4 to 100%) respectively with a median follow-up of 55·5 months. Circulating IFN-γ secreting LMP1 and LMP2a-specific T cells within the peripheral blood corresponded with decline in plasma EBV DNA levels in patients. Adoptive transfer of LMP1/2a CTLs in ENKTCL patients is a safe and effective postremission therapeutic approach. Further randomized studies will be needed to define the role of EBV-CTLs in preventing relapse of ENKTCL. PMID:26017177

  17. Long-term Outcome of Extranodal NK/T Cell Lymphoma Patients Treated With Postremission Therapy Using EBV LMP1 and LMP2a-specific CTLs.

    PubMed

    Cho, Seok-Goo; Kim, Nayoun; Sohn, Hyun-Jung; Lee, Suk Kyeong; Oh, Sang Taek; Lee, Hyun-Joo; Cho, Hyun-Il; Yim, Hyeon Woo; Jung, Seung Eun; Park, Gyeongsin; Oh, Joo Hyun; Choi, Byung-Ock; Kim, Sung Won; Kim, Soo Whan; Chung, Nak Gyun; Lee, Jong Wook; Hong, Young Seon; Kim, Tai-Gyu

    2015-08-01

    Extranodal NK/T-cell lymphoma (ENKTCL) is associated with latent Epstein-Barr virus (EBV) infection and frequent relapse even after complete response (CR) to intensive chemotherapy and radiotherapy. The expression of EBV proteins in the tumor provides targets for adoptive immunotherapy with antigen-specific cytotoxic T cells (CTL). To evaluate the efficacy and safety of EBV latent membrane protein (LMP)-1 and LMP-2a-specific CTLs (LMP1/2a CTLs) stimulated with LMP1/2a RNA-transferred dendritic cells, we treated 10 ENKTCL patients who showed complete response to induction therapy. Patients who completed and responded to chemotherapy, radiotherapy, and/or high-dose therapy followed by stem cell transplantation (HDT/SCT) were eligible to receive eight doses of 2 × 10(7) LMP1/2a CTLs/m(2). Following infusion, there were no immediate or delayed toxicities. The 4-year overall survival (OS) and progression-free survival (PFS) were 100%, and 90% (95% CI: 71.4 to 100%) respectively with a median follow-up of 55·5 months. Circulating IFN-γ secreting LMP1 and LMP2a-specific T cells within the peripheral blood corresponded with decline in plasma EBV DNA levels in patients. Adoptive transfer of LMP1/2a CTLs in ENKTCL patients is a safe and effective postremission therapeutic approach. Further randomized studies will be needed to define the role of EBV-CTLs in preventing relapse of ENKTCL. PMID:26017177

  18. Lower numbers of natural killer T cells in HIV-1 and Mycobacterium leprae co-infected patients

    PubMed Central

    Carvalho, Karina I; Bruno, Fernanda R; Snyder-Cappione, Jennifer E; Maeda, Solange M; Tomimori, Jane; Xavier, Marilia B; Haslett, Patrick A; Nixon, Douglas F; Kallas, Esper G

    2012-01-01

    Natural killer T (NKT) cells are a heterogeneous population of lymphocytes that recognize antigens presented by CD1d and have attracted attention because of their potential role linking innate and adaptive immune responses. Peripheral NKT cells display a memory-activated phenotype and can rapidly secrete large amounts of pro-inflammatory cytokines upon antigenic activation. In this study, we evaluated NKT cells in the context of patients co-infected with HIV-1 and Mycobacterium leprae. The volunteers were enrolled into four groups: 22 healthy controls, 23 HIV-1-infected patients, 20 patients with leprosy and 17 patients with leprosy and HIV-1-infection. Flow cytometry and ELISPOT assays were performed on peripheral blood mononuclear cells. We demonstrated that patients co-infected with HIV-1 and M. leprae have significantly lower NKT cell frequencies [median 0.022%, interquartile range (IQR): 0.007–0.051] in the peripheral blood when compared with healthy subjects (median 0.077%, IQR: 0.032–0.405, P < 0.01) or HIV-1 mono-infected patients (median 0.072%, IQR: 0.030–0.160, P < 0.05). Also, more NKT cells from co-infected patients secreted interferon-γ after stimulation with DimerX, when compared with leprosy mono-infected patients (P = 0.05). These results suggest that NKT cells are decreased in frequency in HIV-1 and M. leprae co-infected patients compared with HIV-1 mono-infected patients alone, but are at a more activated state. Innate immunity in human subjects is strongly influenced by their spectrum of chronic infections, and in HIV-1-infected subjects, a concurrent mycobacterial infection probably hyper-activates and lowers circulating NKT cell numbers. PMID:22269018

  19. Celiac Disease-Related Inflammation Is Marked by Reduction of Nkp44/Nkp46-Double Positive Natural Killer Cells

    PubMed Central

    Marafini, Irene; Monteleone, Ivan; Di Fusco, Davide; Sedda, Silvia; Cupi, Maria Laura; Fina, Daniele; Paoluzi, Alessandro Omero; Pallone, Francesco; Monteleone, Giovanni

    2016-01-01

    Introduction and Aim Natural killer (NK) cells are a first line of defence against viruses and down-regulation of NK cell cytotoxic receptors represents one of the strategies by which viruses escape the host’s immune system. Since onset of celiac disease (CD), a gluten-driven enteropathy, has been associated with viral infections, we examined whether CD-associated inflammation is characterized by abnormal distribution of NK cell receptors involved in recognition of viral-infected cells. Materials and Methods Intraepithelial mononuclear cells, isolated from duodenal biopsies of active and inactive CD patients and healthy controls (CTR) and jejunal specimens of obese subjects undergoing gastro-intestinal bypass, were analysed for NK cell markers by flow-cytometry. Expression of granzyme B, interleukin (IL)-22 and tumor necrosis factor (TNF)-α was as assessed in freshly isolated and toll-like receptor (TLR) ligand-stimulated cells. Results The percentages of total NK cells and NKT cells did not significantly differ between CD patients and CTR. In active CD, the fractions of NKp30+ NK cells, NKG2D+ NK cells and NKG2D+ NKT cells were significantly increased as compared to inactive CD patients and CTR. In contrast, CD-associated inflammation was marked by diminished presence of NKG2A+ NK cells and NKG2A+ NKT cells. The fractions of NK cells and NKT cells expressing either NKp44 or NKp46 did not differ between CD and controls, but in CD less NK cells and NKT cells co-expressed these receptors. NKp44/NKp46-double positive cells produced granzyme B and IL-22 but not TNF-α and responded to TLR ligands with enhanced expression of granzyme B. Conclusions These data indicate that active phase of CD associates with reduced presence of NKp44/NKp46-double positive NK cells and NKT cells in the epithelial compartment. PMID:27171408

  20. Human Invariant Natural Killer T cells possess immune-modulating functions during Aspergillus infection.

    PubMed

    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. PMID:26483428

  1. Essential functions for ID proteins at multiple checkpoints in natural killer T cell development

    PubMed Central

    Verykokakis, Mihalis; Krishnamoorthy, Veena; Iavarone, Antonio; Lasorella, Anna; Sigvardsson, Mikael; Kee, Barbara L.

    2013-01-01

    Invariant natural killer T (iNKT) cells display characteristics of both adaptive and innate lymphoid cells (ILCs). Like other ILCs, iNKT cells constitutively express ID proteins, which antagonize the E protein transcription factors that are essential for adaptive lymphocyte development. However, unlike ILCs, ID2 is not essential for thymic iNKT cell development. Here we demonstrated that ID2 and ID3 redundantly promoted iNKT cell lineage specification involving the induction of the signature transcription factor PLZF and that ID3 was critical for development of TBET-dependent NKT1 cells. In contrast, both ID2 and ID3 limited iNKT cell numbers by enforcing the post-selection checkpoint in conventional thymocytes. Therefore, iNKT cells show both adaptive and innate-like requirements for ID proteins at distinct checkpoints during iNKT cell development. PMID:24244015

  2. The Alpha and Omega of Galactosylceramides in T Cell Immune Function*

    PubMed Central

    Birkholz, Alysia M.; Howell, Amy R.; Kronenberg, Mitchell

    2015-01-01

    Glycosphingolipids are a subgroup of glycolipids that contain an amino alcohol sphingoid base linked to sugars. They are found in the membranes of cells ranging from bacteria to vertebrates. This group of lipids is known to stimulate the immune system through activation of a type of white blood cell known as natural killer T cell (NKT cell). Here we summarize the extensive research that has been done to identify the structures of natural glycolipids that stimulate NKT cells and to determine how these antigens are recognized. We also review studies designed to understand how glycolipid variants, both natural and synthetic, can alter the responses of NKT cells, leading to dramatic changes in the global immune response. PMID:25947378

  3. Invariant natural killer T cells and their ligands: focus on multiple sclerosis

    PubMed Central

    O'Keeffe, Joan; Podbielska, Maria; Hogan, Edward L

    2015-01-01

    Invariant natural killer T (iNKT) cells are an innate population of T cells identified by the expression of an invariant T-cell receptor and reactivity to lipid-based antigens complexed with CD1d. They account for a small percentage of lymphocytes, but are extremely potent and play central roles in immunity to infection, in some cancers, and in autoimmunity. The list of relevant stimulatory lipids and glycolipid antigens now includes a range of endogenous self-antigens including the myelin-derived acetylated galactosylceramides. Recent progress in studies to identify the nature of lipid recognition for iNKT cells in autoimmune diseases like multiple sclerosis is likely to foster the development of therapeutic strategies aimed at harnessing iNKT cell activity. PMID:25976210

  4. Preparation, characterisation and entrapment of a non-glycosidic threitol ceramide into liposomes for presentation to invariant natural killer T cells

    PubMed Central

    Kaur, Randip; Chen, Jili; Dawoodji, Amina; Cerundolo, Vincenzo; Garcia-Diaz, Yoel R.; Wojno, Justyna; Cox, Liam R.; Besra, Gurdyal S; Moghaddam, Behfar; Perrie, Yvonne

    2013-01-01

    Dendritic cells (DCs) are able to present glycolipids to invariant natural killer T (iNKT) cells in vivo. Very few compounds have been found that stimulate iNKT cells and of these the best-characterised is the glycolipid α-galactosylceramide (α-GalCer 1), which stimulates the production of large quantities of IFNγ and IL-4. However, αGalCer leads to overstimulation of iNKT cells. It has been demonstrated that the αGalCer analogue, threitol ceramide (ThrCer 2), successfully activates iNKT cells and overcomes the problematic iNKT cell activation-induced anergy. In this study, ThrCer 2 has been inserted into the bilayers of liposomes composed of a neutral lipid, 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) or dimethyldioctadecylammonium bromide (DDA), a cationic lipid. Incorporation efficiencies of ThrCer within the liposomes was 96 % for DSPC liposomes and 80 % for DDA liposomes with the vesicle size (large multilamellar vs small unilamellar vesicles) making no significant difference. Langmuir-Blodgett studies suggest both DSPC and DDA stack within the monolayer co-operatively with the ThrCer molecules with no condensing effect. In terms of cellular responses IFNγ secretion was higher for cells treated with small DDA liposomes compared to the other liposome formulations, suggesting that ThrCer encapsulation in this liposome formulation resulted in a higher uptake by DCs. PMID:21283989

  5. Helminth-Induced Interleukin-4 Abrogates Invariant Natural Killer T Cell Activation-Associated Clearance of Bacterial Infection

    PubMed Central

    Hsieh, Yi-Ju; Fu, Chi-Ling

    2014-01-01

    Helminth infections affect 1 billion people worldwide and render these individuals susceptible to bacterial coinfection through incompletely understood mechanisms. This includes urinary tract coinfection by bacteria and Schistosoma haematobium worms, the etiologic agent of urogenital schistosomiasis. To study the mechanisms of S. haematobium-bacterial urinary tract coinfections, we combined the first tractable model of urogenital schistosomiasis with an established mouse model of bacterial urinary tract infection (UTI). A single bladder exposure to S. haematobium eggs triggers interleukin-4 (IL-4) production and makes BALB/c mice susceptible to bacterial UTI when they are otherwise resistant. Ablation of IL-4 receptor alpha (IL-4Rα) signaling restored the baseline resistance of BALB/c mice to bacterial UTI despite prior exposure to S. haematobium eggs. Interestingly, numbers of NKT cells were decreased in coexposed versus bacterially monoinfected bladders. Given that schistosome-induced, non-natural killer T (NKT) cell leukocyte infiltration may dilute NKT cell numbers in the bladders of coexposed mice without exerting a specific functional effect on these cells, we next examined NKT cell biology on a per-cell basis. Invariant NKT (iNKT) cells from coexposed mice expressed less gamma interferon (IFN-γ) per cell than did those from mice with UTI alone. Moreover, coexposure resulted in lower CD1d expression in bladder antigen-presenting cells (APC) than did bacterial UTI alone in an IL-4Rα-dependent fashion. Finally, coexposed mice were protected from prolonged bacterial infection by administration of α-galactosylceramide, an iNKT cell agonist. Our findings point to a previously unappreciated role for helminth-induced IL-4 in impairment of iNKT cell-mediated clearance of bacterial coexposure. PMID:24643536

  6. Innate lymphoid cells and natural killer T cells in the gastrointestinal tract immune system.

    PubMed

    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. PMID:25287236

  7. Efficacy of ABX196, a new NKT agonist, in prophylactic human vaccination

    PubMed Central

    Tefit, Josianne Nitcheu; Crabé, Sandrine; Orlandini, Bernard; Nell, Haylene; Bendelac, Albert; Deng, Shenglou; Savage, Paul B.; Teyton, Luc; Serra, Vincent

    2014-01-01

    We have assessed the immune-regulatory and adjuvant activities of a synthetic glycolipid, ABX196, a novel analog of the parental compound α-GalCer. As expected, ABX196 demonstrated a measurable and significant adjuvant effect in mice and monkeys with no appreciable toxicity at the doses used to promote immune responses. We performed a phase I/II dose escalation study of ABX196 in healthy volunteers, with the objectives to evaluate its safety profile, as well as its ability to be utilized as an adjuvant in the context of a prophylactic vaccine against hepatitis B. ABX196 was administered at three doses: 0.2, 0.4, and 2.0µg, in fourty-four subjects. In all individuals injected with ABX196, peripheral blood NKT cells displayed hallmarks of activation, and 45% of them had measurable circulating IFN-γ 24 hours after the first administration. More importantly, the addition of ABX196 to the very poorly immunogenic HBs antigen resulted in protective anti-HBs antibody responses in a majority of patients, demonstrating the adjuvant properties of ABX196 in human. Further analysis of the cohort of subjects receiving ABX196 with HBs antigen also indicates that a single injection appears sufficient to provide protection. A limited set of adverse events linked to the systemic delivery of ABX196 and access to the liver, is discussed in the context of formulation and the need to limit transport of ABX196 to secondary lymphoid tissues for maximal efficacy (Eudra-CT 2012-001566-15). PMID:25218293

  8. Efficacy of ABX196, a new NKT agonist, in prophylactic human vaccination.

    PubMed

    Tefit, Josianne Nitcheu; Crabé, Sandrine; Orlandini, Bernard; Nell, Haylene; Bendelac, Albert; Deng, Shenglou; Savage, Paul B; Teyton, Luc; Serra, Vincent

    2014-10-21

    We have assessed the immune-regulatory and adjuvant activities of a synthetic glycolipid, ABX196, a novel analog of the parental compound α-GalCer. As expected, ABX196 demonstrated a measurable and significant adjuvant effect in mice and monkeys with no appreciable toxicity at the doses used to promote immune responses. We performed a phase I/II dose escalation study of ABX196 in healthy volunteers, with the objectives to evaluate its safety profile, as well as its ability to be utilized as an adjuvant in the context of a prophylactic vaccine against hepatitis B. ABX196 was administered at three doses: 0.2, 0.4, and 2.0μg, in 44 subjects. In all the individuals injected with ABX196, peripheral blood NKT cells displayed hallmarks of activation, and 45% of them had measurable circulating IFN-γ 24h after the first administration. More importantly, the addition of ABX196 to the very poorly immunogenic HBs antigen resulted in protective anti-HBs antibody responses in majority of patients, demonstrating the adjuvant properties of ABX196 in human. Further analysis of the cohort of subjects receiving ABX196 with HBs antigen also indicates that a single injection appears sufficient to provide protection. A limited set of adverse events linked to the systemic delivery of ABX196 and access to the liver, is discussed in the context of formulation and the need to limit transport of ABX196 to secondary lymphoid tissues for maximal efficacy (Eudra-CT 2012-001566-15). PMID:25218293

  9. NKG2D is a Key Receptor for Recognition of Bladder Cancer Cells by IL-2-Activated NK Cells and BCG Promotes NK Cell Activation

    PubMed Central

    García-Cuesta, Eva María; López-Cobo, Sheila; Álvarez-Maestro, Mario; Esteso, Gloria; Romera-Cárdenas, Gema; Rey, Mercedes; Cassady-Cain, Robin L.; Linares, Ana; Valés-Gómez, Alejandro; Reyburn, Hugh Thomson; Martínez-Piñeiro, Luis; Valés-Gómez, Mar

    2015-01-01

    Intravesical instillation of bacillus Calmette–Guérin (BCG) is used to treat superficial bladder cancer, either papillary tumors (after transurethral resection) or high-grade flat carcinomas (carcinoma in situ), reducing recurrence in about 70% of patients. Initially, BCG was proposed to work through an inflammatory response, mediated by phagocytic uptake of mycobacterial antigens and cytokine release. More recently, other immune effectors such as monocytes, natural killer (NK), and NKT cells have been suggested to play a role in this immune response. Here, we provide a comprehensive study of multiple bladder cancer cell lines as putative targets for immune cells and evaluated their recognition by NK cells in the presence and absence of BCG. We describe that different bladder cancer cells can express multiple activating and inhibitory ligands for NK cells. Recognition of bladder cancer cells depended mainly on NKG2D, with a contribution from NKp46. Surprisingly, exposure to BCG did not affect the immune phenotype of bladder cells nor increased NK cell recognition of purified IL-2-activated cell lines. However, NK cells were activated efficiently when BCG was included in mixed lymphocyte cultures, suggesting that NK activation after mycobacteria treatment requires the collaboration of various immune cells. We also analyzed the percentage of NK cells in peripheral blood of a cohort of bladder cancer patients treated with BCG. The total numbers of NK cells did not vary during treatment, indicating that a more detailed study of NK cell activation in the tumor site will be required to evaluate the response in each patient. PMID:26106390

  10. T-Cell-Specific Deletion of Map3k1 Reveals the Critical Role for Mekk1 and Jnks in Cdkn1b-Dependent Proliferative Expansion.

    PubMed

    Suddason, Tesha; Anwar, Saba; Charlaftis, Nikolaos; Gallagher, Ewen

    2016-01-26

    MAPK signaling is important for T lymphocyte development, homeostasis, and effector responses. To better understand the role of Mekk1 (encoded by Map3k1) in T cells, we conditionally deleted Map3k1 in Lck(Cre/+)Map3k1(f/f) mice, and these display larger iNKT cell populations within the liver, spleen, and bone marrow. Mekk1 signaling controls splenic and liver iNKT cell expansion in response to glycolipid antigen. Lck(Cre/+)Map3k1(f/f) mice have enhanced liver damage in response to glycolipid antigen. Mekk1 regulates Jnk activation in iNKT cells and binds and transfers Lys63-linked poly-ubiquitin onto Carma1. Map3k1 is critical for the regulation of p27(Kip1) (encoded by Cdkn1b). PMID:26774476

  11. T-Cell-Specific Deletion of Map3k1 Reveals the Critical Role for Mekk1 and Jnks in Cdkn1b-Dependent Proliferative Expansion

    PubMed Central

    Suddason, Tesha; Anwar, Saba; Charlaftis, Nikolaos; Gallagher, Ewen

    2016-01-01

    Summary MAPK signaling is important for T lymphocyte development, homeostasis, and effector responses. To better understand the role of Mekk1 (encoded by Map3k1) in T cells, we conditionally deleted Map3k1 in LckCre/+Map3k1f/f mice, and these display larger iNKT cell populations within the liver, spleen, and bone marrow. Mekk1 signaling controls splenic and liver iNKT cell expansion in response to glycolipid antigen. LckCre/+Map3k1f/f mice have enhanced liver damage in response to glycolipid antigen. Mekk1 regulates Jnk activation in iNKT cells and binds and transfers Lys63-linked poly-ubiquitin onto Carma1. Map3k1 is critical for the regulation of p27Kip1 (encoded by Cdkn1b). PMID:26774476

  12. Mycobacterial phosphatidylinositol mannoside is a natural antigen for CD1d-restricted T cells

    PubMed Central

    Fischer, Karsten; Scotet, Emmanuel; Niemeyer, Marcus; Koebernick, Heidrun; Zerrahn, Jens; Maillet, Sophie; Hurwitz, Robert; Kursar, Mischo; Bonneville, Marc; Kaufmann, Stefan H. E.; Schaible, Ulrich E.

    2004-01-01

    A group of T cells recognizes glycolipids presented by molecules of the CD1 family. The CD1d-restricted natural killer T cells (NKT cells) are primarily considered to be self-reactive. By employing CD1d-binding and T cell assays, the following structural parameters for presentation by CD1d were defined for a number of mycobacterial and mammalian lipids: two acyl chains facilitated binding, and a polar head group was essential for T cell recognition. Of the mycobacterial lipids tested, only a phosphatidylinositol mannoside (PIM) fulfilled the requirements for CD1d binding and NKT cell stimulation. This PIM activated human and murine NKT cells via CD1d, thereby triggering antigen-specific IFN-γ production and cell-mediated cytotoxicity, and PIM-loaded CD1d tetramers identified a subpopulation of murine and human NKT cells. This phospholipid, therefore, represents a mycobacterial antigen recognized by T cells in the context of CD1d. PMID:15243159

  13. Expression of activation-induced cytidine deaminase enhances the clearance of pneumococcal pneumonia: evidence of a subpopulation of protective anti-pneumococcal B1a cells.

    PubMed

    Yamamoto, Natsuo; Kerfoot, Steven M; Hutchinson, Andrew T; Dela Cruz, Charles S; Nakazawa, Naomi; Szczepanik, Marian; Majewska-Szczepanik, Monika; Nazimek, Katarzyna; Ohana, Noboru; Bryniarski, Krzysztof; Mori, Tsutomu; Muramatsu, Masamichi; Kanemitsu, Keiji; Askenase, Philip W

    2016-01-01

    We describe a protective early acquired immune response to pneumococcal pneumonia that is mediated by a subset of B1a cells. Mice deficient in B1 cells (xid), or activation-induced cytidine deaminase (AID(-/-) ), or invariant natural killer T (iNKT) cells (Jα18(-/-) ), or interleukin-13 (IL-13(-/-) ) had impaired early clearance of pneumococci in the lung, compared with wild-type mice. In contrast, AID(-/-) mice adoptively transferred with AID(+/+) B1a cells, significantly cleared bacteria from the lungs as early as 3 days post infection. We show that this early bacterial clearance corresponds to an allergic contact sensitivity-like cutaneous response, probably due to a subpopulation of initiating B1a cells. In the pneumonia model, these B1a cells were found to secrete higher affinity antigen-specific IgM. In addition, as in contact sensitivity, iNKT cells were required for the anti-pneumococcal B1a cell initiating response, probably through early production of IL-13, given that IL-13(-/-) mice also failed to clear infection. Our study is the first to demonstrate the importance of AID in generating an appropriate B1a cell response to pathogenic bacteria. Given the antibody affinity and pneumonia resistance data, natural IgM produced by conventional B1a cells are not responsible for pneumonia clearance compared with the AID-dependent subset. PMID:26456931

  14. PyNTTTTGT and CpG immunostimulatory oligonucleotides: effect on granulocyte/monocyte colony-stimulating factor (GM-CSF) secretion by human CD56+ (NK and NKT) cells.

    PubMed

    Rodriguez, Juan M; Marchicio, José; López, Mariela; Ziblat, Andrea; Elias, Fernanda; Fló, Juan; López, Ricardo A; Horn, David; Zorzopulos, Jorge; Montaner, Alejandro D

    2015-01-01

    CD56+ cells have been recognized as being involved in bridging the innate and acquired immune systems. Herein, we assessed the effect of two major classes of immunostimulatory oligonucleotides (ODNs), PyNTTTTGT and CpG, on CD56+ cells. Incubation of human peripheral blood mononuclear cells (hPBMC) with some of these ODNs led to secretion of significant amounts of interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α) and granulocyte/monocyte colony-stimulating factor (GM-CSF), but only if interleukin 2 (IL2) was present. IMT504, the prototype of the PyNTTTTGT ODN class, was the most active. GM-CSF secretion was very efficient when non-CpG ODNs with high T content and PyNTTTTGT motifs lacking CpGs were used. On the other hand, CpG ODNs and IFNα inhibited this GM-CSF secretion. Selective cell type removal from hPBMC indicated that CD56+ cells were responsible for GM-CSF secretion and that plasmacytoid dendritic cells (PDCs) regulate this process. In addition, PyNTTTTGT ODNs inhibited the IFNα secretion induced by CpG ODNs in PDCs by interference with the TLR9 signaling pathway. Since IFNα is essential for CD56+ stimulation by CpG ODNs, there is a reciprocal interference of CpG and PyNTTTTGT ODNs when acting on this cell population. This suggests that these synthetic ODNs mimic different natural alarm signals for activation of the immune system. PMID:25706946

  15. PyNTTTTGT and CpG Immunostimulatory Oligonucleotides: Effect on Granulocyte/Monocyte Colony-Stimulating Factor (GM-CSF) Secretion by Human CD56+ (NK and NKT) Cells

    PubMed Central

    Rodriguez, Juan M.; Marchicio, José; López, Mariela; Ziblat, Andrea; Elias, Fernanda; Fló, Juan; López, Ricardo A.; Horn, David; Zorzopulos, Jorge; Montaner, Alejandro D.

    2015-01-01

    CD56+ cells have been recognized as being involved in bridging the innate and acquired immune systems. Herein, we assessed the effect of two major classes of immunostimulatory oligonucleotides (ODNs), PyNTTTTGT and CpG, on CD56+ cells. Incubation of human peripheral blood mononuclear cells (hPBMC) with some of these ODNs led to secretion of significant amounts of interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α) and granulocyte/monocyte colony-stimulating factor (GM-CSF), but only if interleukin 2 (IL2) was present. IMT504, the prototype of the PyNTTTTGT ODN class, was the most active. GM-CSF secretion was very efficient when non-CpG ODNs with high T content and PyNTTTTGT motifs lacking CpGs were used. On the other hand, CpG ODNs and IFNα inhibited this GM-CSF secretion. Selective cell type removal from hPBMC indicated that CD56+ cells were responsible for GM-CSF secretion and that plasmacytoid dendritic cells (PDCs) regulate this process. In addition, PyNTTTTGT ODNs inhibited the IFNα secretion induced by CpG ODNs in PDCs by interference with the TLR9 signaling pathway. Since IFNα is essential for CD56+ stimulation by CpG ODNs, there is a reciprocal interference of CpG and PyNTTTTGT ODNs when acting on this cell population. This suggests that these synthetic ODNs mimic different natural alarm signals for activation of the immune system. PMID:25706946

  16. Solar cell activation system

    SciTech Connect

    Apelian, L.

    1983-07-05

    A system for activating solar cells involves the use of phosphorescent paint, the light from which is amplified by a thin magnifying lens and used to activate solar cells. In a typical system, a member painted with phosphorescent paint is mounted adjacent a thin magnifying lens which focuses the light on a predetermined array of sensitive cells such as selenium, cadmium or silicon, mounted on a plastic board. A one-sided mirror is mounted adjacent the cells to reflect the light back onto said cells for purposes of further intensification. The cells may be coupled to rechargeable batteries or used to directly power a small radio or watch.

  17. Invariant natural killer T cells direct B cell responses to cognate lipid antigen in an interleukin 21- dependent manner

    PubMed Central

    King, Irah L; Fortier, Anne; Tighe, Michael; Dibble, John; Watts, Gerald FM; Veerapen, Natacha; Haberman, Ann M; Besral, Gurdyal S; Mohrs, Markus; Brenner, Michael B; Leadbetter, Elizabeth A

    2013-01-01

    Murine invariant natural killer T (iNKT) cells provide cognate and non-cognate help for lipid and protein-specific B cells, respectively. However, the long term B cell outcome following cognate iNKT help is currently unknown. We show that cognate iNKT cell help resulted in a B cell differentiation program characterized by extrafollicular plasmablasts, germinal center formation, affinity maturation and a robust primary IgG antibody response that was uniquely dependent on iNKT-derived interleukin 21 (IL-21). However, cognate iNKT cell help did not generate an enhanced humoral memory response. Thus, iNKT cell cognate help for lipid-specific B cells induces a unique signature which is a hybrid of classic T-dependent (TD) and T-independent type 2 (TI-2) B cell responses. PMID:22120118

  18. The bispecific immunoligand ULBP2-aCEA redirects natural killer cells to tumor cells and reveals potent anti-tumor activity against colon carcinoma.

    PubMed

    Rothe, Achim; Jachimowicz, Ron D; Borchmann, Sven; Madlener, Marie; Keßler, Jörg; Reiners, Katrin S; Sauer, Maike; Hansen, Hinrich P; Ullrich, Roland T; Chatterjee, Sampurna; Borchmann, Peter; Yazaki, Paul; Koslowsky, Thomas C; Engert, Andreas; Heukamp, Lukas C; Hallek, Michael; von Strandmann, Elke Pogge

    2014-06-15

    NKG2D, an activating receptor expressed on NK cells and T cells, is critically involved in tumor immunosurveillance. In this study, we explored the potential therapeutic utility of the NKG2D ligand ULBP2 for the treatment of colon carcinoma. To this end we designed a fusion protein consisting of human ULBP2 and an antibody-derived single chain targeting the tumor carcinoembryonic antigen (CEA). The bispecific recombinant fusion protein re-directed NK cells towards malignant cells by binding to both, tumor cells and NK cells, and triggered NK cell-mediated target cell killing in vitro. Moreover, tumor growth was significantly delayed in a syngeneic colon carcinoma mouse model in response to immunoligand treatment. The anti-tumor activity could be attributed to the stimulation of immune cells with an elevated expression of the activation marker CD69 on NK, T and NKT cells and the infiltration of CD45+ immune cells into the solid tumor. In summary, it was demonstrated that immunoligands provide specific tumor targeting by NK cells and exert anti-tumor activity in vitro and in vivo. This technology represents a novel immunotherapeutic strategy for solid tumors with the potential to be further developed for clinical applications. PMID:24242212

  19. Differential Expression of NK Receptors CD94 and NKG2A by T Cells in Rheumatoid Arthritis Patients in Remission Compared to Active Disease

    PubMed Central

    Walsh, Ceara E.; Ryan, Elizabeth J.; O’Farrelly, Cliona; Golden-Mason, Lucy; FitzGerald, Oliver; Veale, Douglas J.; Bresnihan, Barry; Fearon, Ursula

    2011-01-01

    Objective TNF inhibitors (TNFi) have revolutionised the treatment of rheumatoid arthritis (RA). Natural killer (NK) cells and Natural Killer Cell Receptor+ T (NKT) cells comprise important effector lymphocytes whose activity is tightly regulated through surface NK receptors (NKRs). Dysregulation of NKRs in patients with autoimmune diseases has been shown, however little is known regarding NKRs expression in patients with TNFi-induced remission and in those who maintain remission vs disease flare following TNFi withdrawal. Methods Patients with RA were recruited for this study, (i) RA patients in clinical remission following a minimum of one year of TNFi therapy (n = −15); (2) Active RA patients, not currently or ever receiving TNFi (n = 18); and healthy control volunteers (n = 15). Patients in remission were divided into two groups: those who were maintained on TNFi and those who withdrew from TNFi and maintained on DMARDS. All patients underwent full clinical assessment. Peripheral blood mononuclear cells were isolated and NKR (CD94, NKG2A, CD161, CD69, CD57, CD158a, CD158b) expression on T-(CD3+CD56−), NK-(CD3−CD56+) and NKT-(CD3+CD56+) cells was determined by flow cytometry. Results Following TNFi withdrawal, percentages and numbers of circulating T cells, NK cells or NKT cell populations were unchanged in patients in remission versus active RA or HCs. Expression of the NKRs CD161, CD57, CD94 and NKG2A was significantly increased on CD3+CD56-T cells from patients in remission compared to active RA (p<0.05). CD3+CD56-T cell expression of CD94 and NKG2A was significantly increased in patients who remained in remission compared with patients whose disease flared (p<0.05), with no differences observed for CD161 and CD57. CD3+CD56− cell expression of NKG2A was inversely related to DAS28 (r = −0.612, p<0.005). Conclusion High CD94/NKG2A expression by T cells was demonstrated in remission patients following TNFi therapy compared to active RA

  20. E and Id proteins influence invariant Natural Killer T cell sublineage differentiation and proliferation

    PubMed Central

    D'Cruz, Louise M.; Stradner, Martin H.; Yang, Cliff Y.; Goldrath, Ananda W.

    2014-01-01

    Disease outcome is known to be influenced by defined subsets of invariant Natural Killer T (iNKT) cells residing in distinct locations within peripheral tissue. However, the factors governing the development of these unique iNKT sublineages during thymic development are unknown. Here we explored the mechanism by which E protein transcription factors and their negative regulators, the Id proteins control the development of iNKT sublineages after positive selection. We found that E proteins directly bound the PLZF promoter and were required for expression of this lineage-defining transcription factor and for the maturation and expansion of thymic iNKT cells. Moreover, expression of the negative regulators of E proteins, Id2 and Id3, defined distinct iNKT cell sublineages. Id3 was expressed in PLZFhigh NKT2 cells and loss of Id3 allowed for increased thymic iNKT cell expansion and abundance of the PLZF+ NKT2 sublineage. Id2 was expressed in TBET+ NKT1 cells and both Id proteins were required for the formation of this sublineage. Thus, we provide insight into E and Id protein regulation of iNKT cell proliferation and differentiation to specific sublineages during development in the thymus. PMID:24470501

  1. Expression of CD11c Is Associated with Unconventional Activated T Cell Subsets with High Migratory Potential

    PubMed Central

    Cantero, Jon; Tarrats, Antoni; Fernández, Marco Antonio; Sumoy, Lauro; Rodolosse, Annie; McSorley, Stephen J.

    2016-01-01

    CD11c is an α integrin classically employed to define myeloid dendritic cells. Although there is little information about CD11c expression on human T cells, mouse models have shown an association of CD11c expression with functionally relevant T cell subsets. In the context of genital tract infection, we have previously observed increased expression of CD11c in circulating T cells from mice and women. Microarray analyses of activated effector T cells expressing CD11c derived from naïve mice demonstrated enrichment for natural killer (NK) associated genes. Here we find that murine CD11c+ T cells analyzed by flow cytometry display markers associated with non-conventional T cell subsets, including γδ T cells and invariant natural killer T (iNKT) cells. However, in women, only γδ T cells and CD8+ T cells were enriched within the CD11c fraction of blood and cervical tissue. These CD11c+ cells were highly activated and had greater interferon (IFN)-γ secretory capacity than CD11c- T cells. Furthermore, circulating CD11c+ T cells were associated with the expression of multiple adhesion molecules in women, suggesting that these cells have high tissue homing potential. These data suggest that CD11c expression distinguishes a population of circulating T cells during bacterial infection with innate capacity and mucosal homing potential. PMID:27119555

  2. Cytokine expression by invariant natural killer T cells is tightly regulated throughout development and settings of type-2 inflammation

    PubMed Central

    O'Brien, T F; Bao, K; Dell'Aringa, M; Ang, W X G; Abraham, S; Reinhardt, R L

    2016-01-01

    Invariant natural killer T (iNKT) cells produce cytokines interleukin-4 (IL-4) and IL-13 during type-2 inflammatory responses. However, the nature in which iNKT cells acquire type-2 cytokine competency and the precise contribution of iNKT cell–derived IL-4 and IL-13 in vivo remains unclear. Using IL-13-reporter mice to fate-map cytokine–expressing cells in vivo, this study reveals that thymic iNKT cells express IL-13 early during development, and this IL-13-expressing intermediate gives rise to mature iNKT1, iNKT2, and iNKT17 subsets. IL-4 and IL-13 reporter mice also reveal that effector iNKT2 cells produce IL-4 but little IL-13 in settings of type-2 inflammation. The preferential production of IL-4 over IL-13 in iNKT2 cells results in part from their reduced GATA-3 expression. In summary, this work helps integrate current models of iNKT cell development, and further establishes non-coordinate production of IL-4 and IL-13 as the predominant pattern of type-2 cytokine expression among innate cells in vivo. PMID:26349658

  3. T-cell death following immune activation is mediated by mitochondria-localized SARM.

    PubMed

    Panneerselvam, P; Singh, L P; Selvarajan, V; Chng, W J; Ng, S B; Tan, N S; Ho, B; Chen, J; Ding, J L

    2013-03-01

    Following acute-phase infection, activated T cells are terminated to achieve immune homeostasis, failure of which results in lymphoproliferative and autoimmune diseases. We report that sterile α- and heat armadillo-motif-containing protein (SARM), the most conserved Toll-like receptors adaptor, is proapoptotic during T-cell immune response. SARM expression is significantly reduced in natural killer (NK)/T lymphoma patients compared with healthy individuals, suggesting that decreased SARM supports NK/T-cell proliferation. T cells knocked down of SARM survived and proliferated more significantly compared with wild-type T cells following influenza infection in vivo. During activation of cytotoxic T cells, the SARM level fell before rising, correlating inversely with cell proliferation and subsequent T-cell clearance. SARM knockdown rescued T cells from both activation- and neglect-induced cell deaths. The mitochondria-localized SARM triggers intrinsic apoptosis by generating reactive oxygen species and depolarizing the mitochondrial potential. The proapoptotic function is attributable to the C-terminal sterile alpha motif and Toll/interleukin-1 receptor domains. Mechanistically, SARM mediates intrinsic apoptosis via B cell lymphoma-2 (Bcl-2) family members. SARM suppresses B cell lymphoma-extra large (Bcl-xL) and downregulates extracellular signal-regulated kinase phosphorylation, which are cell survival effectors. Overexpression of Bcl-xL and double knockout of Bcl-2 associated X protein and Bcl-2 homologous antagonist killer substantially reduced SARM-induced apoptosis. Collectively, we have shown how T-cell death following infection is mediated by SARM-induced intrinsic apoptosis, which is crucial for T-cell homeostasis. PMID:23175186

  4. The tumor antigen N-glycolyl-GM3 is a human CD1d ligand capable of mediating B cell and natural killer T cell interaction.

    PubMed

    Gentilini, M Virginia; Pérez, M Eugenia; Fernández, Pablo Mariano; Fainboim, Leonardo; Arana, Eloísa

    2016-05-01

    The expression of N-glycolyl-monosialodihexosyl-ganglioside (NGcGM3) in humans is restricted to cancer cells; therefore, it is a tumor antigen. There are measurable quantities of circulating anti-NGcGM3 antibodies (aNGcGM3 Abs) in human serum. Interestingly, some people have circulating Ag-specific immunoglobulins G (IgGs) that are capable of complement mediated cytotoxicity against NGcGM3 positive cells, which is relevant for tumor surveillance. In light of the chemical nature of Ag, we postulated it as a candidate ligand for CD1d. Furthermore, we hypothesize that the immune mechanism involved in the generation of these Abs entails cross talk between B lymphocytes (Bc) and invariant natural killer T cells (iNKT). Combining cellular techniques, such as flow cytometry and biochemical assays, we demonstrated that CD1d binds to NGcGM3 and that human Bc present NGcGM3 in a CD1d context according to two alternative strategies. We also showed that paraformaldehyde treatment of cells expressing CD1d affects the presentation. Finally, by co-culturing primary human Bc with iNKT and measuring Ki-67 expression, we detected a reproducible increment in the proliferation of the iNKT population when Ag was on the medium. Our findings identify a novel, endogenous, human CD1d ligand, which is sufficiently competent to stimulate iNKT. We postulate that CD1d-restricted Bc presentation of NGcGM3 drives effective iNKT activation, an immunological mechanism that has not been previously described for humans, which may contribute to understanding aNGcGM3 occurrence. PMID:26969612

  5. Vitamin D and 1,25(OH)2D regulation of T cells.

    PubMed

    Cantorna, Margherita T; Snyder, Lindsay; Lin, Yang-Ding; Yang, Linlin

    2015-04-01

    Vitamin D is a direct and indirect regulator of T cells. The mechanisms by which vitamin D directly regulates T cells are reviewed and new primary data on the effects of 1,25 dihydroxyvitamin D (1,25(OH)2D) on human invariant natural killer (iNK)T cells is presented. The in vivo effects of vitamin D on murine T cells include inhibition of T cell proliferation, inhibition of IFN-γ, IL-17 and induction of IL-4. Experiments in mice demonstrate that the effectiveness of 1,25(OH)2D requires NKT cells, IL-10, the IL-10R and IL-4. Comparisons of mouse and human T cells show that 1,25(OH)2D inhibits IL-17 and IFN-γ, and induces T regulatory cells and IL-4. IL-4 was induced by 1,25(OH)2D in mouse and human iNKT cells. Activation for 72 h was required for optimal expression of the vitamin D receptor (VDR) in human and mouse T and iNKT cells. In addition, T cells are potential autocrine sources of 1,25(OH)2D but again only 48-72 h after activation. Together the data support the late effects of vitamin D on diseases like inflammatory bowel disease and multiple sclerosis where reducing IL-17 and IFN-γ, while inducing IL-4 and IL-10, would be beneficial. PMID:25912039

  6. CD1d-restricted antigen presentation by Vγ9Vδ2-T cells requires trogocytosis.

    PubMed

    Schneiders, Famke L; Prodöhl, Jan; Ruben, Jurjen M; O'Toole, Tom; Scheper, Rik J; Bonneville, Marc; Scotet, Emmanuel; Verheul, Henk M W; de Gruijl, Tanja D; van der Vliet, Hans J

    2014-08-01

    CD1d-restricted invariant natural killer T cells (iNKT) constitute an important immunoregulatory T-cell subset that can be activated by the synthetic glycolipid α-galactosylceramide (α-GalCer) and play a dominant role in antitumor immunity. Clinical trials with α-GalCer-pulsed monocyte-derived dendritic cells (moDC) have shown anecdotal antitumor activity in advanced cancer. It was reported that phosphoantigen (pAg)-activated Vγ9Vδ2-T cells can acquire characteristics of professional antigen-presenting cells (APC). Considering the clinical immunotherapeutic applications, Vγ9Vδ2-T APC can offer important advantages over moDC, potentially constituting an attractive novel APC platform. Here, we demonstrate that Vγ9Vδ2-T APC can present antigens to iNKT. However, this does not result from de novo synthesis of CD1d by Vγ9Vδ2-T, but critically depends on trogocytosis of CD1d-containing membrane fragments from pAg-expressing cells. CD1d-expressing Vγ9Vδ2-T cells were able to activate iNKT in a CD1d-restricted and α-GalCer-dependent fashion. Although α-GalCer-loaded moDC outperformed Vγ9Vδ2-T APC on a per cell basis, Vγ9Vδ2-T APC possess unique features with respect to clinical immunotherapeutic application that make them an interesting platform for consideration in future clinical trials. PMID:24934445

  7. Yeast culture has anti-inflammatory effects and specifically activates NK cells.

    PubMed

    Jensen, G S; Patterson, K M; Yoon, I

    2008-11-01

    Yeast culture is widely used in animal feed and has been linked to beneficial effects on animal health and production. This study examined the anti-oxidant and immunomodulating effects of a consumable yeast culture, XP, in vitro. An aqueous extract of XP contained anti-oxidants able to enter living cells and quench free radicals. The XP extract induced an increased expression of CD69 and CD25 on NK and NKT cells, and an increased cytotoxic response to K562 tumor cells. The XP extract amplified ProteinA-induced B cell activation in vitro, as measured by induction of the CD86 antigen on B lymphoblasts in 7-day cultures. The data show an anti-inflammatory effect of the XP extract in conjunction with activation of NK cells and B lymphocytes in vitro. Further in vivo studies are needed to examine the impact of XP in animals with bacterial and viral infections, as well as around the time of vaccination. PMID:17915321

  8. CD1d-restricted peripheral T cell lymphoma in mice and humans.

    PubMed

    Bachy, Emmanuel; Urb, Mirjam; Chandra, Shilpi; Robinot, Rémy; Bricard, Gabriel; de Bernard, Simon; Traverse-Glehen, Alexandra; Gazzo, Sophie; Blond, Olivier; Khurana, Archana; Baseggio, Lucile; Heavican, Tayla; Ffrench, Martine; Crispatzu, Giuliano; Mondière, Paul; Schrader, Alexandra; Taillardet, Morgan; Thaunat, Olivier; Martin, Nadine; Dalle, Stéphane; Le Garff-Tavernier, Magali; Salles, Gilles; Lachuer, Joel; Hermine, Olivier; Asnafi, Vahid; Roussel, Mikael; Lamy, Thierry; Herling, Marco; Iqbal, Javeed; Buffat, Laurent; Marche, Patrice N; Gaulard, Philippe; Kronenberg, Mitchell; Defrance, Thierry; Genestier, Laurent

    2016-05-01

    Peripheral T cell lymphomas (PTCLs) are a heterogeneous entity of neoplasms with poor prognosis, lack of effective therapies, and a largely unknown pathophysiology. Identifying the mechanism of lymphomagenesis and cell-of-origin from which PTCLs arise is crucial for the development of efficient treatment strategies. In addition to the well-described thymic lymphomas, we found that p53-deficient mice also developed mature PTCLs that did not originate from conventional T cells but from CD1d-restricted NKT cells. PTCLs showed phenotypic features of activated NKT cells, such as PD-1 up-regulation and loss of NK1.1 expression. Injections of heat-killed Streptococcus pneumonia, known to express glycolipid antigens activating NKT cells, increased the incidence of these PTCLs, whereas Escherichia coli injection did not. Gene expression profile analyses indicated a significant down-regulation of genes in the TCR signaling pathway in PTCL, a common feature of chronically activated T cells. Targeting TCR signaling pathway in lymphoma cells, either with cyclosporine A or anti-CD1d blocking antibody, prolonged mice survival. Importantly, we identified human CD1d-restricted lymphoma cells within Vδ1 TCR-expressing PTCL. These results define a new subtype of PTCL and pave the way for the development of blocking anti-CD1d antibody for therapeutic purposes in humans. PMID:27069116

  9. Coevolution of MHC genes (LMP/TAP/class Ia; NKT-class Ib; NKp30-B7H6): Lessons from cold-blooded vertebrates

    PubMed Central

    Ohta, Yuko; Flajnik, Martin F.

    2015-01-01

    Summary Comparative immunology provides the long view of what is conserved across all vertebrate taxa versus what is specific to particular organisms or group of organisms. Regarding the major histocompatibility complex (MHC) and coevolution, three striking cases have been revealed in cold-blooded vertebrates: lineages of class Ia antigen-processing and -presenting genes, evolutionary conservation of NKT-class Ib recognition, and the ancient emergence of the natural cytotoxicity receptor NKp30 and its ligand B7H6. While coevolution of transporter associated with antigen processing (TAP) and class Ia has been documented in endothermic birds and two mammals, lineages of LMP7 are restricted to ectotherms. The unambiguous discovery of natural killer T (NKT) cells in Xenopus demonstrated that NKT cells are not restricted to mammals and are likely to have emerged at the same time in evolution as classical α/β and γ/δ T cells. NK cell receptors evolve at a rapid rate, and orthologues are nearly impossible to identify in different vertebrate classes. By contrast, we have detected NKp30 in all gnathostomes, except in species where it was lost. The recently discovered ligand of NKp30, B7H6, shows strong signs of coevolution with NKp30 throughout evolution, i.e. coincident loss or expansion of both genes in some species. NKp30 also offers an attractive IgSF candidate for the invasion of the RAG transposon, which is believed to have initiated T-cell receptor/immunoglobulin adaptive immunity. Besides reviewing these intriguing features of MHC evolution and coevolution, we offer suggestions for future studies and propose a model for the primordial or proto MHC. PMID:26284468

  10. Coevolution of MHC genes (LMP/TAP/class Ia, NKT-class Ib, NKp30-B7H6): lessons from cold-blooded vertebrates.

    PubMed

    Ohta, Yuko; Flajnik, Martin F

    2015-09-01

    Comparative immunology provides the long view of what is conserved across all vertebrate taxa versus what is specific to particular organisms or group of organisms. Regarding the major histocompatibility complex (MHC) and coevolution, three striking cases have been revealed in cold-blooded vertebrates: lineages of class Ia antigen-processing and -presenting genes, evolutionary conservation of NKT-class Ib recognition, and the ancient emergence of the natural cytotoxicity receptor NKp30 and its ligand B7H6. While coevolution of transporter associated with antigen processing (TAP) and class Ia has been documented in endothermic birds and two mammals, lineages of LMP7 are restricted to ectotherms. The unambiguous discovery of natural killer T (NKT) cells in Xenopus demonstrated that NKT cells are not restricted to mammals and are likely to have emerged at the same time in evolution as classical α/β and γ/δ T cells. NK cell receptors evolve at a rapid rate, and orthologues are nearly impossible to identify in different vertebrate classes. By contrast, we have detected NKp30 in all gnathostomes, except in species where it was lost. The recently discovered ligand of NKp30, B7H6, shows strong signs of coevolution with NKp30 throughout evolution, i.e. coincident loss or expansion of both genes in some species. NKp30 also offers an attractive IgSF candidate for the invasion of the RAG transposon, which is believed to have initiated T-cell receptor/immunoglobulin adaptive immunity. Besides reviewing these intriguing features of MHC evolution and coevolution, we offer suggestions for future studies and propose a model for the primordial or proto MHC. PMID:26284468

  11. TLR9-induced miR-155 and Ets-1 decrease expression of CD1d on B cells in SLE.

    PubMed

    Liu, Fei; Fan, Hongye; Ren, Deshan; Dong, Guanjun; Hu, Erling; Ji, Jianjian; Hou, Yayi

    2015-07-01

    B cells present lipid antigens to CD1d-restricted invariant natural killer T (iNKT) cells to maintain autoimmune tolerance, and this process is disrupted in systemic lupus erythematosus (SLE). Inflammation may inhibit CD1d expression to exacerbate the pathology of lupus. However, how inflammation regulates CD1d expression on B cells is unclear in SLE. In the present study, we showed that the surface expression of CD1d on B cells from SLE mice was decreased and that stimulation of inflammatory responses through TLR9 decreased the membrane and total CD1d levels of CD1d on B cells. Moreover, inflammation-related microRNA-155 (miR-155) negatively correlated with the expression of CD1d in B cells. miR-155 directly targeted the 3'-untranslated region (3'-UTR) of CD1d upon TLR9 activation in both humans and mice. The inhibitory effects of miR-155 on CD1d expression in B cells impaired their antigen-presenting capacity to iNKT cells. In addition, Ets-1, a susceptibility gene of SLE, also directly regulated the expression of the CD1d gene at the transcriptional level. These findings provide new insight into the mechanism underlying decreased CD1d expression on B cells in SLE, suggesting that inhibition of inflammation may increase CD1d expression in B cells to ameliorate SLE via modulating iNKT cells. PMID:25929465

  12. Innate-like functions of natural killer T cell subsets result from highly divergent gene programs.

    PubMed

    Engel, Isaac; Seumois, Grégory; Chavez, Lukas; Samaniego-Castruita, Daniela; White, Brandie; Chawla, Ashu; Mock, Dennis; Vijayanand, Pandurangan; Kronenberg, Mitchell

    2016-06-01

    Natural killer T cells (NKT cells) have stimulatory or inhibitory effects on the immune response that can be attributed in part to the existence of functional subsets of NKT cells. These subsets have been characterized only on the basis of the differential expression of a few transcription factors and cell-surface molecules. Here we have analyzed purified populations of thymic NKT cell subsets at both the transcriptomic level and epigenomic level and by single-cell RNA sequencing. Our data indicated that despite their similar antigen specificity, the functional NKT cell subsets were highly divergent populations with many gene-expression and epigenetic differences. Therefore, the thymus 'imprints' distinct gene programs on subsets of innate-like NKT cells that probably impart differences in proliferative capacity, homing, and effector functions. PMID:27089380

  13. Fluorescence activated cell sorting.

    NASA Technical Reports Server (NTRS)

    Bonner, W. A.; Hulett, H. R.; Sweet, R. G.; Herzenberg, L. A.

    1972-01-01

    An instrument has been developed for sorting biological cells. The cells are rendered differentially fluorescent and incorporated into a small liquid stream illuminated by a laser beam. The cells pass sequentially through the beam, and fluorescent light from the cells gives rise to electrical signals. The stream is broken into a series of uniform size drops downstream of the laser. The cell signals are used to give appropriate electrostatic charges to drops containing the cells. The drops then pass between two charged plates and are deflected to appropriate containers. The system has proved capable of providing fractions containing large numbers of viable cells highly enriched in a particular functional type.

  14. Development and function of invariant natural killer T cells producing T(h)2- and T(h)17-cytokines.

    PubMed

    Watarai, Hiroshi; Sekine-Kondo, Etsuko; Shigeura, Tomokuni; Motomura, Yasutaka; Yasuda, Takuwa; Satoh, Rumi; Yoshida, Hisahiro; Kubo, Masato; Kawamoto, Hiroshi; Koseki, Haruhiko; Taniguchi, Masaru

    2012-02-01

    There is heterogeneity in invariant natural killer T (iNKT) cells based on the expression of CD4 and the IL-17 receptor B (IL-17RB), a receptor for IL-25 which is a key factor in T(H)2 immunity. However, the development pathway and precise function of these iNKT cell subtypes remain unknown. IL-17RB⁺iNKT cells are present in the thymic CD44⁺/⁻ NK1.1⁻ population and develop normally even in the absence of IL-15, which is required for maturation and homeostasis of IL-17RB⁻iNKT cells producing IFN-γ. These results suggest that iNKT cells contain at least two subtypes, IL-17RB⁺ and IL-17RB⁻ subsets. The IL-17RB⁺iNKT subtypes can be further divided into two subtypes on the basis of CD4 expression both in the thymus and in the periphery. CD4⁺ IL-17RB⁺iNKT cells produce T(H)2 (IL-13), T(H)9 (IL-9 and IL-10), and T(H)17 (IL-17A and IL-22) cytokines in response to IL-25 in an E4BP4-dependent fashion, whereas CD4⁻ IL-17RB⁺iNKT cells are a retinoic acid receptor-related orphan receptor (ROR)γt⁺ subset producing T(H)17 cytokines upon stimulation with IL-23 in an E4BP4-independent fashion. These IL-17RB⁺iNKT cell subtypes are abundantly present in the lung in the steady state and mediate the pathogenesis in virus-induced airway hyperreactivity (AHR). In this study we demonstrated that the IL-17RB⁺iNKT cell subsets develop distinct from classical iNKT cell developmental stages in the thymus and play important roles in the pathogenesis of airway diseases. PMID:22346732

  15. Interferon-γ constrains cytokine production of group 2 innate lymphoid cells.

    PubMed

    Kudo, Fujimi; Ikutani, Masashi; Seki, Yoichi; Otsubo, Takeshi; Kawamura, Yuki I; Dohi, Taeko; Oshima, Kenshiro; Hattori, Masahira; Nakae, Susumu; Takatsu, Kiyoshi; Takaki, Satoshi

    2016-01-01

    Group 2 innate lymphoid cells (ILC2s) produce a significant amount of interleukin-5 (IL-5), which supports eosinophil responses in various tissues; they also produce IL-13, which induces mucus production and contributes to tissue repair or fibrosis. The ILC2s are activated by alarmins, such as IL-33 released from epithelia, macrophages and natural killer T (NKT) cells in response to infection and allergen exposure, leading to epithelial injury. We examined gene expression in lung ILC2s and found that ILC2s expressed Ifngr1, the receptor for interferon-γ (IFN-γ). Interferon-γ severely inhibited IL-5 and IL-13 production by lung and kidney ILC2s. To evaluate the effects in vivo, we used α-galactosylceramide (α-GalCer) to induce NKT cells to produce IL-33 and IFN-γ. Intraperitoneal injection of α-GalCer in mice induced NKT cell activation resulting in IL-5 and IL-13 production by ILC2s. Administration of anti-IFN-γ together with α-GalCer significantly enhanced the production of IL-5 and IL-13 by ILC2s in lung and kidney. Conversely, cytokine production from ILC2s was markedly suppressed after injection of exogenous IL-33 in Il33(-/-) mice pre-treated with α-GalCer. Hence, IFN-γ induced or already present in tissues can impact downstream pleiotropic functions mediated by ILC2s, such as inflammation and tissue repair. PMID:26425820

  16. Regulation of experimental autoimmune encephalomyelitis by natural killer (NK) cells.

    PubMed

    Zhang, B; Yamamura, T; Kondo, T; Fujiwara, M; Tabira, T

    1997-11-17

    In this report, we establish a regulatory role of natural killer (NK) cells in experimental autoimmune encephalomyelitis (EAE), a prototype T helper cell type 1 (Th1)-mediated disease. Active sensitization of C57BL/6 (B6) mice with the myelin oligodendrocyte glycoprotein (MOG)35-55 peptide induces a mild form of monophasic EAE. When mice were deprived of NK cells by antibody treatment before immunization, they developed a more serious form of EAE associated with relapse. Aggravation of EAE by NK cell deletion was also seen in beta 2-microglobulin-/- (beta 2m-/-) mice, indicating that NK cells can play a regulatory role in a manner independent of CD8+ T cells or NK1.1+ T cells (NK-T cells). The disease enhancement was associated with augmentation of T cell proliferation and production of Th1 cytokines in response to MOG35-55. EAE passively induced by the MOG35-55-specific T cell line was also enhanced by NK cell deletion in B6, beta 2m-/-, and recombination activation gene 2 (RAG-2)-/- mice, indicating that the regulation by NK cells can be independent of T, B, or NK-T cells. We further showed that NK cells inhibit T cell proliferation triggered by antigen or cytokine stimulation. Taken together, we conclude that NK cells are an important regulator for EAE in both induction and effector phases. PMID:9362528

  17. Atypical natural killer T-cell receptor recognition of CD1d–lipid antigens

    PubMed Central

    Le Nours, Jérôme; Praveena, T.; Pellicci, Daniel G.; Gherardin, Nicholas A.; Ross, Fiona J.; Lim, Ricky T.; Besra, Gurdyal S.; Keshipeddy, Santosh; Richardson, Stewart K.; Howell, Amy R.; Gras, Stephanie; Godfrey, Dale I.; Rossjohn, Jamie; Uldrich, Adam P.

    2016-01-01

    Crucial to Natural Killer T (NKT) cell function is the interaction between their T-cell receptor (TCR) and CD1d-antigen complex. However, the diversity of the NKT cell repertoire and the ensuing interactions with CD1d-antigen remain unclear. We describe an atypical population of CD1d–α-galactosylceramide (α-GalCer)-reactive human NKT cells that differ markedly from the prototypical TRAV10-TRAJ18-TRBV25-1+ type I NKT cell repertoire. These cells express a range of TCR α- and β-chains that show differential recognition of glycolipid antigens. Two atypical NKT TCRs (TRAV21-TRAJ8-TRBV7–8 and TRAV12-3-TRAJ27-TRBV6-5) bind orthogonally over the A′-pocket of CD1d, adopting distinct docking modes that contrast with the docking mode of all type I NKT TCR-CD1d-antigen complexes. Moreover, the interactions with α-GalCer differ between the type I and these atypical NKT TCRs. Accordingly, diverse NKT TCR repertoire usage manifests in varied docking strategies and specificities towards CD1d–α-GalCer and related antigens, thus providing far greater scope for diverse glycolipid antigen recognition. PMID:26875526

  18. Atypical natural killer T-cell receptor recognition of CD1d-lipid antigens.

    PubMed

    Le Nours, Jérôme; Praveena, T; Pellicci, Daniel G; Gherardin, Nicholas A; Ross, Fiona J; Lim, Ricky T; Besra, Gurdyal S; Keshipeddy, Santosh; Richardson, Stewart K; Howell, Amy R; Gras, Stephanie; Godfrey, Dale I; Rossjohn, Jamie; Uldrich, Adam P

    2016-01-01

    Crucial to Natural Killer T (NKT) cell function is the interaction between their T-cell receptor (TCR) and CD1d-antigen complex. However, the diversity of the NKT cell repertoire and the ensuing interactions with CD1d-antigen remain unclear. We describe an atypical population of CD1d-α-galactosylceramide (α-GalCer)-reactive human NKT cells that differ markedly from the prototypical TRAV10-TRAJ18-TRBV25-1(+) type I NKT cell repertoire. These cells express a range of TCR α- and β-chains that show differential recognition of glycolipid antigens. Two atypical NKT TCRs (TRAV21-TRAJ8-TRBV7-8 and TRAV12-3-TRAJ27-TRBV6-5) bind orthogonally over the A'-pocket of CD1d, adopting distinct docking modes that contrast with the docking mode of all type I NKT TCR-CD1d-antigen complexes. Moreover, the interactions with α-GalCer differ between the type I and these atypical NKT TCRs. Accordingly, diverse NKT TCR repertoire usage manifests in varied docking strategies and specificities towards CD1d-α-GalCer and related antigens, thus providing far greater scope for diverse glycolipid antigen recognition. PMID:26875526

  19. Mouse and Human CD1d-Self-Lipid Complexes Are Recognized Differently by Murine Invariant Natural Killer T Cell Receptors

    PubMed Central

    Guo, Tingxi; Chamoto, Kenji; Nakatsugawa, Munehide; Ochi, Toshiki; Yamashita, Yuki; Anczurowski, Mark; Butler, Marcus O.; Hirano, Naoto

    2016-01-01

    Invariant natural killer T (iNKT) cells recognize self-lipids presented by CD1d through characteristic TCRs, which mainly consist of the invariant Vα14-Jα18 TCRα chain and Vβ8.2, 7 or 2 TCRβ chains with hypervariable CDR3β sequences in mice. The iNKT cell-CD1d axis is conserved between humans and mice, and human CD1d reactivity of murine iNKT cells have been described. However, the detailed differences between the recognition of human and mouse CD1d bound to various self-lipids by mouse iNKT TCRs are largely unknown. In this study, we generated a de novo murine iNKT TCR repertoire with a wider range of autoreactivity compared with that of naturally occurring peripheral iNKT TCRs. Vβ8.2 mouse iNKT TCRs capable of recognizing the human CD1d-self-lipid tetramer were identified, although such clones were not detectable in the Vβ7 or Vβ2 iNKT TCR repertoire. In line with previously reports, clonotypic Vβ8.2 iNKT TCRs with unique CDR3β loops did not discriminate among lipids presented by mouse CD1d. Unexpectedly, however, these iNKT TCRs showed greater ligand selectivity toward human CD1d presenting the same lipids. Our findings demonstrated that the recognition of mouse and human CD1d-self-lipid complexes by murine iNKT TCRs is not conserved, thereby further elucidating the differences between cognate and cross-species reactivity of self-antigens by mouse iNKT TCRs. PMID:27213277

  20. Reduced proportions of natural killer T cells are present in the relatives of lupus patients and are associated with autoimmunity

    PubMed Central

    Wither, Joan; Cai, Yong-chun; Lim, Sooyeol; McKenzie, Tamara; Roslin, Nicole; Claudio, Jaime O; Cooper, Glinda S; Hudson, Thomas J; Paterson, Andrew D; Greenwood, Celia MT; Gladman, Dafna; Pope, Janet; Pineau, Christian A; Smith, C Douglas; Hanly, John G; Peschken, Christine; Boire, Gilles; Fortin, Paul R

    2008-01-01

    Introduction Systemic lupus erythematosus is a genetically complex disease. Currently, the precise allelic polymorphisms associated with this condition remain largely unidentified. In part this reflects the fact that multiple genes, each having a relatively minor effect, act in concert to produce disease. Given this complexity, analysis of subclinical phenotypes may aid in the identification of susceptibility alleles. Here, we used flow cytometry to investigate whether some of the immune abnormalities that are seen in the peripheral blood lymphocyte population of lupus patients are seen in their first-degree relatives. Methods Peripheral blood mononuclear cells were isolated from the subjects, stained with fluorochrome-conjugated monoclonal antibodies to identify various cellular subsets, and analyzed by flow cytometry. Results We found reduced proportions of natural killer (NK)T cells among 367 first-degree relatives of lupus patients as compared with 102 control individuals. There were also slightly increased proportions of memory B and T cells, suggesting increased chronic low-grade activation of the immune system in first-degree relatives. However, only the deficiency of NKT cells was associated with a positive anti-nuclear antibody test and clinical autoimmune disease in family members. There was a significant association between mean parental, sibling, and proband values for the proportion of NKT cells, suggesting that this is a heritable trait. Conclusions The findings suggest that analysis of cellular phenotypes may enhance the ability to detect subclinical lupus and that genetically determined altered immunoregulation by NKT cells predisposes first-degree relatives of lupus patients to the development of autoimmunity. PMID:18783591

  1. STAT3 transcription factor is constitutively activated and is oncogenic in nasal-type NK/T-cell lymphoma

    PubMed Central

    Coppo, Paul; Gouilleux-Gruart, Valérie; Huang, Yenlin; Bouhlal, Hicham; Bouamar, Hakim; Bouchet, Sandrine; Perrot, Christine; Vieillard, Vincent; Dartigues, Peggy; Gaulard, Philippe; Agbalika, Félix; Douay, Luc; Lassoued, Kaiss; Gorin, Norbert-Claude

    2009-01-01

    Nasal-type natural killer (NK) cell lymphoma is an infrequent aggressive malignant disease with very poor prognosis. We aimed to explore the possible role of the transcription factor STAT3 in the pathophysiology of this malignancy, as it was involved in oncogenesis and chemoresistance. For this, we established and characterized a continuous interleukin 2-dependent NK cell line (MEC04) from a patient with a fatal nasal-type NK cell lymphoma. Cells harbored poor cytotoxic activity against K562 cells, and spontaneously secreted interferon-γ, IL-10 and vascular-endothelium growth factor in vitro. STAT3 was phosphorylated in Y705 dimerization residue in MEC04 cells and restricted to the nucleus. Y705 STAT3 phosphorylation involved JAK2, since exposure of cells to AG490 inhibitor inhibited Y705 STAT3 phosphorylation. By using recombinant transducible TAT-STAT3β (βisoform), TAT-STAT3Y705F (a STAT3 protein mutated on Y705 residue which prevents STAT3 dimerization), and peptides inhibiting specifically STAT3 dimerization, we inhibited STAT3 phosphorylation and cell growth, with cell death induction. Finally, STAT3 was phosphorylated in Y705 residue in the nuclei of lymphoma cells in 8/9 patients with nasal-type NK/T cell lymphoma and in YT, another NK cell line. Our results suggest that STAT3 protein has a major role in the oncogenic process of nasal-type NK cell lymphomas, and may represent a promising therapeutical target. PMID:19421230

  2. Preserved Function of Circulating Invariant Natural Killer T Cells in Patients With Chronic Hepatitis B Virus Infection

    PubMed Central

    Zhu, Haoxiang; Zhang, Yongmei; Liu, Hongyan; Zhang, Yijun; Kang, Yaoyue; Mao, Richeng; Yang, Feifei; Zhou, Dapeng; Zhang, Jiming

    2015-01-01

    Abstract To date, the role of invariant natural killer T (iNKT) cells in chronic hepatitis B virus (HBV) infection is not fully understood. In previous reports, iNKT cells were identified by indirect methods. However, discrepancies regarding the prevalence and function of iNKT cells during HBV infection were observed. In this study, we have devised a direct, highly specific CD1d tetramer-based methodology to test whether patients with HBV infection have associated iNKT-cell defects. In our study, a total of 93 chronic HBV-infected patients and 30 healthy individuals (as control) were enrolled. The prevalence of iNKT cells, their cytokine producing capacity, and in vitro expansion were determined by flow cytometric analysis with CD1d tetramer staining. Our observation demonstrated that there was no significant difference in circulating CD1d-tetramer positive iNKT cell numbers between HBV-infected patients and healthy controls. The capacity of iNKT cells to produce IFN-γ or IL-4 as well as their in vitro expansion was also comparable between these 2 groups. However, among chronic HBV-infected patients, a decrease in iNKT cell-number was observed in chronic hepatitis B (CHB) and cirrhosis patients in comparison to that in immune tolerant (IT) patients. These results indicated that patients with chronic HBV infection may have normal prevalence and preserved function of circulating iNKT cells. And antiviral therapy with nucleot(s)ide analogue does not alter the frequency and function of circulating iNKT cells in chronic Hepatitis B patients.

  3. CD1d- and MR1-Restricted T Cells in Sepsis

    PubMed Central

    Szabo, Peter A.; Anantha, Ram V.; Shaler, Christopher R.; McCormick, John K.; Haeryfar, S.M. Mansour

    2015-01-01

    Dysregulated immune responses to infection, such as those encountered in sepsis, can be catastrophic. Sepsis is typically triggered by an overwhelming systemic response to an infectious agent(s) and is associated with high morbidity and mortality even under optimal critical care. Recent studies have implicated unconventional, innate-like T lymphocytes, including CD1d- and MR1-restricted T cells as effectors and/or regulators of inflammatory responses during sepsis. These cell types are typified by invariant natural killer T (iNKT) cells, variant NKT (vNKT) cells, and mucosa-associated invariant T (MAIT) cells. iNKT and vNKT cells are CD1d-restricted, lipid-reactive cells with remarkable immunoregulatory properties. MAIT cells participate in antimicrobial defense, and are restricted by major histocompatibility complex-related protein 1 (MR1), which displays microbe-derived vitamin B metabolites. Importantly, NKT and MAIT cells are rapid and potent producers of immunomodulatory cytokines. Therefore, they may be considered attractive targets during the early hyperinflammatory phase of sepsis when immediate interventions are urgently needed, and also in later phases when adjuvant immunotherapies could potentially reverse the dangerous state of immunosuppression. We will highlight recent findings that point to the significance or the therapeutic potentials of NKT and MAIT cells in sepsis and will also discuss what lies ahead in research in this area. PMID:26322041

  4. Multitarget magnetic activated cell sorter

    PubMed Central

    Adams, Jonathan D.; Kim, Unyoung; Soh, H. Tom

    2008-01-01

    Magnetic selection allows high-throughput sorting of target cells based on surface markers, and it is extensively used in biotechnology for a wide range of applications from in vitro diagnostics to cell-based therapies. However, existing methods can only perform separation based on a single parameter (i.e., the presence or absence of magnetization), and therefore, the simultaneous sorting of multiple targets at high levels of purity, recovery, and throughput remains a challenge. In this work, we present an alternative system, the multitarget magnetic activated cell sorter (MT-MACS), which makes use of microfluidics technology to achieve simultaneous spatially-addressable sorting of multiple target cell types in a continuous-flow manner. We used the MT-MACS device to purify 2 types of target cells, which had been labeled via target-specific affinity reagents with 2 different magnetic tags with distinct saturation magnetization and size. The device was engineered so that the combined effects of the hydrodynamic force produced from the laminar flow and the magnetophoretic force produced from patterned ferromagnetic structures within the microchannel result in the selective purification of the differentially labeled target cells into multiple independent outlets. We demonstrate here the capability to simultaneously sort multiple magnetic tags with >90% purity and >5,000-fold enrichment and multiple bacterial cell types with >90% purity and >500-fold enrichment at a throughput of 109 cells per hour. PMID:19015523

  5. CD1d induction in solid tumor cells by histone deacetylase inhibitors through inhibition of HDAC1/2 and activation of Sp1.

    PubMed

    Yang, Pei-Ming; Lin, Pei-Jie; Chen, Ching-Chow

    2012-04-01

    CD1d is a MHC class-like molecule that presents glycolipids to natural killer T (NKT) cells, then regulates innate and adaptive immunity. The regulation of CD1d gene expression in solid tumors is still largely unknown. Gene expression can be epigenetically regulated by DNA methylation and histone acetylation. We found that histone deacetylase inhibitors, trichostatin A (TSA) and suberoylanilide hydroxamic acid (SAHA), induced CD1d gene expression in human (A549 and NCI-H292) and mouse (TC-1 and B16/F0) cancer cells. Simultaneous knockdown of HDAC1 and 2 induced CD1d gene expression. Sp1 inhibitor mitramycin A (MTM) blocked TSA- and SAHA-induced CD1d mRNA expression and Sp1 luciferase activity. Co-transfection of GAL4-Sp1 and Fc-luciferase reporters demonstrated that TSA and SAHA induced Sp1 luciferase reporter activity by enhancing Sp1 transactivation activity. The binding of Sp1 to CD1d promoter and histone H3 acetylation on Sp1 sites were increased by TSA and SAHA. These results indicate that TSA and SAHA could up-regulate CD1d expression in tumor cells through inhibition of HDAC1/2 and activation of Sp1. PMID:22419072

  6. Culture and properties of adipose-derived mesenchymal stem cells: characteristics in vitro and immunosuppression in vivo

    PubMed Central

    Cao, Fujiang; Liu, Tao; Xu, Yunqiang; Xu, Dongdong; Feng, Shiqing

    2015-01-01

    Objective: To compare the two sources of adipose and bone marrow derived mesenchymal stem cells (BMSCs and AMSCs) in immune regulation and to evaluate the therapeutic effects of AMSCs on Con A induced hepatitis and the possible mechanism involved in it. Methods: We isolated bone marrow and adipose derived mesenchymal stem cells respectively and compared their differences on T lymphocyte activation, proliferation and suppression. We also test the anti-apoptosis ability of AMSCs on LO2 cell line. The effects of intravenous infusion of AMSCs on liver damage were also tested and we detected donor AMSCs in liver of recipient and their effects on the activity of intrahepatic NKT cells. Results: BMSCs and AMSCs were similar in cell phenotype and the difference existed only in the expression of CD106. The results showed that the capacity of suppressing T cells proliferation and activation was weakened in AMSCs. AMSCs ameliorated liver damage and this effect was time and dose dependent. We detected donor AMSCs in liver of recipient which suggested tissue damage could be a clue for AMSCs migration. We also found AMSCs suppress the activity of intrahepatic NKT cells, but this suppress effects was not restricted in liver only, but the whole body. Conclusion: Cell origin and abundance are decisive factors in stem cells applications and with the same premise of AMSCs and BMSCs, adipose tissue is a more promising origin source of stem cells. The immunoregulatory features of MSCs might play an important role in various MSCs cellular therapies. PMID:26339336

  7. Multifocal primary cutaneous extranodal NK/T lymphoma nasal type*

    PubMed Central

    de Vasconcelos, Pedro; Ferreira, Cristina; Soares-Almeida, Luís; Filipe, Paulo

    2016-01-01

    Nasal type extranodal NK/T-cell lymphoma is a distinct entity according to the World Health Organization classification. Although 60% to 90% of patients with this disease present with a destructive mass in the midline facial tissues, it may also primarily or secondarily involve extranasal sites, like the skin. We report the case of a 77-year-old patient that came to our department with erythematous plaques of the right leg and eczematous lesions of the trunk. These lesions were biopsied and the patient was diagnosed with extranodal NK/T-cell lymphoma, nasal type. He was treated with multi-agent systemic chemotherapy but died 5 months after diagnosis. This case highlights the rarity and variability of cutaneous features of this disease and its aggressive course and poor prognosis. PMID:27192524

  8. Tracking and treating activated T cells

    PubMed Central

    Kim, N.H.; Nadithe, V.; Elsayed, M.; Merkel, O.M.

    2014-01-01

    Upon activation, T cells of various subsets are the most important mediators in cell-mediated immune responses. Activated T cells play an important role in immune system related diseases such as chronic inflammatory diseases, viral infections, autoimmune disease, transplant rejection, Crohn disease, diabetes, and many more. Therefore, efforts have been made to both visualize and treat activated T cells specifically. This review summarizes imaging approaches and selective therapeutics for activated T cells and gives an outlook on how tracking and treating can be combined into theragnositc agents for activated T cells. PMID:24660025

  9. Id2 regulates hyporesponsive invariant natural killer T cells.

    PubMed

    Stradner, Martin H; Cheung, Kitty P; Lasorella, Anna; Goldrath, Ananda W; D'Cruz, Louise M

    2016-08-01

    While the invariant natural killer T (iNKT)-cell response to primary stimulation with the glycolipid, α-galactosylceramide (αGalCer), is robust, the secondary response to this stimulus is muted resulting in a hyporesponsive state characterized by anti-inflammatory interleukin-10 (IL-10) production and high expression of programmed cell death 1 (PD1) and neuropilin 1 (NRP1). The E protein transcription factors and their negative regulators, the Id proteins, have previously been shown to regulate iNKT cell thymic development, subset differentiation and peripheral survival. Here, we provide evidence that the expression of the transcriptional regulator Id2 is downregulated upon stimulation of iNKT cells with their cognate antigen. Moreover, loss of Id2 expression by iNKT cells resulted in a hyporesponsive state, with splenic Id2-deficient iNKT cells expressing low levels of TBET, high levels of PD1 and NRP1 and production of IL-10 upon stimulation. We propose that downregulation of Id2 expression is an essential component of induction of the anti-inflammatory, hyporesponsive state in iNKT cells. PMID:26880074

  10. Id2 regulates hyporesponsive invariant natural killer T cells

    PubMed Central

    Stradner, Martin H; Cheung, Kitty P; Lasorella, Anna; Goldrath, Ananda W; D’Cruz, Louise M

    2016-01-01

    While the invariant natural killer T (iNKT)-cell response to primary stimulation with the glycolipid, α-galactosylceramide (αGalCer), is robust, the secondary response to this stimulus is muted resulting in a hyporesponsive state characterized by anti-inflammatory interleukin-10 (IL-10) production and high expression of programmed cell death 1 (PD1) and neuropilin 1 (NRP1). The E protein transcription factors and their negative regulators, the Id proteins, have previously been shown to regulate iNKT cell thymic development, subset differentiation and peripheral survival. Here, we provide evidence that the expression of the transcriptional regulator Id2 is downregulated upon stimulation of iNKT cells with their cognate antigen. Moreover, loss of Id2 expression by iNKT cells resulted in a hyporesponsive state, with splenic Id2-deficient iNKT cells expressing low levels of TBET, high levels of PD1 and NRP1 and production of IL-10 upon stimulation. We propose that downregulation of Id2 expression is an essential component of induction of the anti-inflammatory, hyporesponsive state in iNKT cells. PMID:26880074

  11. Viral Evasion of Natural Killer Cell Activation

    PubMed Central

    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

  12. Mechanisms of Cell Propulsion by Active Stresses.

    PubMed

    Carlsson, A E

    2011-07-01

    The mechanisms by which cytoskeletal flows and cell-substrate interactions interact to generate cell motion are explored using a simplified model of the cytoskeleton as a viscous gel containing active stresses. This model yields explicit general results relating cell speed and traction forces to the distributions of active stress and cell-substrate friction. It is found that 1) the cell velocity is given by a function that quantifies the asymmetry of the active-stress distribution, 2) gradients in cell-substrate friction can induce motion even when the active stresses are symmetrically distributed, 3) the traction-force dipole is enhanced by protrusive stresses near the cell edges or contractile stresses near the center of the cell, and 4) the cell velocity depends biphasically on the cell-substrate adhesion strength if active stress is enhanced by adhesion. Specific experimental tests of the calculated dependences are proposed. PMID:21804763

  13. Mechanisms of Cell Propulsion by Active Stresses

    PubMed Central

    Carlsson, A. E.

    2011-01-01

    The mechanisms by which cytoskeletal flows and cell-substrate interactions interact to generate cell motion are explored using a simplified model of the cytoskeleton as a viscous gel containing active stresses. This model yields explicit general results relating cell speed and traction forces to the distributions of active stress and cell-substrate friction. It is found that 1) the cell velocity is given by a function that quantifies the asymmetry of the active-stress distribution, 2) gradients in cell-substrate friction can induce motion even when the active stresses are symmetrically distributed, 3) the traction-force dipole is enhanced by protrusive stresses near the cell edges or contractile stresses near the center of the cell, and 4) the cell velocity depends biphasically on the cell-substrate adhesion strength if active stress is enhanced by adhesion. Specific experimental tests of the calculated dependences are proposed. PMID:21804763

  14. Estrogen Therapy Delays Autoimmune Diabetes and Promotes the Protective Efficiency of Natural Killer T-Cell Activation in Female Nonobese Diabetic Mice.

    PubMed

    Gourdy, Pierre; Bourgeois, Elvire A; Levescot, Anaïs; Pham, Linh; Riant, Elodie; Ahui, Marie-Louise; Damotte, Diane; Gombert, Jean-Marc; Bayard, Francis; Ohlsson, Claes; Arnal, Jean-François; Herbelin, André

    2016-01-01

    Therapeutic strategies focused on restoring immune tolerance remain the main avenue to prevent type 1 diabetes (T1D). Because estrogens potentiate FoxP3+ regulatory T cells (Treg) and invariant natural killer T (iNKT) cells, two regulatory lymphocyte populations that are functionally deficient in nonobese diabetic (NOD) mice, we investigated whether estradiol (E2) therapy influences the course of T1D in this model. To this end, female NOD mice were sc implanted with E2- or placebo-delivering pellets to explore the course of spontaneous and cyclophosphamide-induced diabetes. Treg-depleted and iNKT-cell-deficient (Jα18(-/-)) NOD mice were used to assess the respective involvement of these lymphocyte populations in E2 effects. Early E2 administration (from 4 wk of age) was found to preserve NOD mice from both spontaneous and cyclophosphamide-induced diabetes, and a complete protection was also observed throughout treatment when E2 treatment was initiated after the onset of insulitis (from 12 wk of age). This delayed E2 treatment remained fully effective in Treg-depleted mice but failed to entirely protect Jα18(-/-) mice. Accordingly, E2 administration was shown to restore the cytokine production of iNKT cells in response to in vivo challenge with the cognate ligand α-galactosylceramide. Finally, transient E2 administration potentiated the previously described protective action of α-galactosylceramide treatment in NOD females. This study provides original evidence that E2 therapy strongly protects NOD mice from T1D and reveals the estrogen/iNKT cell axis as a new effective target to counteract diabetes onset at the stage of insulitis. Estrogen-based therapy should thus be considered for T1D prevention. PMID:26485613

  15. Genetic insights into Map3k-dependent proliferative expansion of T cells.

    PubMed

    Suddason, Tesha; Gallagher, Ewen

    2016-08-01

    Mapks are important regulators of T cell proliferative expansion and cell cycle progression. Detailed genetic analysis of unconventional iNKT cells in both Map3k1(ΔKD) and Lck(Cre/+)Map3k1(f/f) mice demonstrated that Mekk1 (encoded by Map3k1) signaling activates Mapks to regulate Cdkn1b (encoding p27(Kip1)) expression and p27(Kip1)-dependent proliferative expansion in response to antigen. Mekk1 signaling and activation of E3 ubiquitin ligase Itch, by a phosphorylation-dependent conformational change, is also an important regulatory mechanism for the control of T helper cell cytokine production. Cdkn1b expression is regulated by Mekk1-dependent signaling in differentiated Th17 cells. Mekk1 is one of the 19 Ste11-like Map3ks, and Mekk1 signaling regulates iNKT cell proliferative expansion in response to glycolipid antigens and T cell homeostasis in the liver. Tak1 (encoded by Map3k7), a related Map3k to Mekk1, similarly regulates the proliferative expansion and homeostasis of T cells in the liver, and this illustrates the importance of multiple Map3ks for mammalian Mapk signaling. PMID:27246297

  16. Mast cells enhance T cell activation: Importance of mast cell-derived TNF

    NASA Astrophysics Data System (ADS)

    Nakae, Susumu; Suto, Hajime; Kakurai, Maki; Sedgwick, Jonathon D.; Tsai, Mindy; Galli, Stephen J.

    2005-05-01

    Mast cells are not only important effector cells in immediate hypersensitivity reactions and immune responses to pathogens but also can contribute to T cell-mediated disorders. However, the mechanisms by which mast cells might influence T cells in such settings are not fully understood. We find that mast cells can enhance proliferation and cytokine production in multiple T cell subsets. Mast cell-dependent enhancement of T cell activation can be promoted by FcRI-dependent mast cell activation, TNF production by both mast cells and T cells, and mast cell-T cell contact. However, at high concentrations of cells, mast cells can promote T cell activation independent of IgE or TNF. Finally, mast cells also can promote T cell activation by means of soluble factors. These findings identify multiple mechanisms by which mast cells can influence T cell proliferation and cytokine production. allergy | asthma | autoimmunity | cytokines | immune response

  17. Effect of cytokine-induced killer cells on immune function in patients with lung cancer

    PubMed Central

    PAN, YANYAN; WU, YUANYUAN; JI, JUN; CAI, HONGJIAO; WANG, HESHUANG; JIANG, YIFAN; SANG, LIMIN; YANG, JIN; GAO, YANYAN; LIU, YING; YIN, LIANGWEI; ZHANG, LI

    2016-01-01

    Cytokine-induced killer (CIK) cells have been used as adoptive immunotherapy in cancer. The present study evaluated the effect of CIK cells on immune function in patients with lung cancer. Patients were divided into three groups, according to the treatment received prior to CIK cell treatment: CIK group (no prior treatment), Che-Sur group (prior chemotherapy and surgery) and Che-Rad group (prior chemotherapy and radiotherapy). Following treatment, the average percentage of cluster of differentiation (CD)3+CD4+, CD3+, natural killer (NK) and NKT cells in peripheral blood was significantly higher than that prior to CIK treatment in the Che-Sur and CIK groups, and the levels of interferon-γ in serum were significantly higher than those prior to CIK treatment in the Che-Sur and CIK groups. On the contrary, the levels of interleukin-10 had decreased in these groups following CIK treatment. Subsequently, patients were divided into three groups according to the percentage of CD3+CD56+ CIK cells that were administered to the patients. The number of NK and NKT cells increased with increasing number of CD3+CD56+ cells. The patients in the CIK and Che-Sur groups were the most benefited ones following CIK treatment, contrarily to those in the Che-Rad group, since the increase in the number of CD3+CD56+ CIK cells in the aforementioned patients enhanced the number of NK cells, which exhibit antitumor activity. PMID:27073559

  18. Myosin II Activity Softens Cells in Suspension

    PubMed Central

    Chan, Chii J.; Ekpenyong, Andrew E.; Golfier, Stefan; Li, Wenhong; Chalut, Kevin J.; Otto, Oliver; Elgeti, Jens; Guck, Jochen; Lautenschläger, Franziska

    2015-01-01

    The cellular cytoskeleton is crucial for many cellular functions such as cell motility and wound healing, as well as other processes that require shape change or force generation. Actin is one cytoskeleton component that regulates cell mechanics. Important properties driving this regulation include the amount of actin, its level of cross-linking, and its coordination with the activity of specific molecular motors like myosin. While studies investigating the contribution of myosin activity to cell mechanics have been performed on cells attached to a substrate, we investigated mechanical properties of cells in suspension. To do this, we used multiple probes for cell mechanics including a microfluidic optical stretcher, a microfluidic microcirculation mimetic, and real-time deformability cytometry. We found that nonadherent blood cells, cells arrested in mitosis, and naturally adherent cells brought into suspension, stiffen and become more solidlike upon myosin inhibition across multiple timescales (milliseconds to minutes). Our results hold across several pharmacological and genetic perturbations targeting myosin. Our findings suggest that myosin II activity contributes to increased whole-cell compliance and fluidity. This finding is contrary to what has been reported for cells attached to a substrate, which stiffen via active myosin driven prestress. Our results establish the importance of myosin II as an active component in modulating suspended cell mechanics, with a functional role distinctly different from that for substrate-adhered cells. PMID:25902426

  19. Myosin II Activity Softens Cells in Suspension.

    PubMed

    Chan, Chii J; Ekpenyong, Andrew E; Golfier, Stefan; Li, Wenhong; Chalut, Kevin J; Otto, Oliver; Elgeti, Jens; Guck, Jochen; Lautenschläger, Franziska

    2015-04-21

    The cellular cytoskeleton is crucial for many cellular functions such as cell motility and wound healing, as well as other processes that require shape change or force generation. Actin is one cytoskeleton component that regulates cell mechanics. Important properties driving this regulation include the amount of actin, its level of cross-linking, and its coordination with the activity of specific molecular motors like myosin. While studies investigating the contribution of myosin activity to cell mechanics have been performed on cells attached to a substrate, we investigated mechanical properties of cells in suspension. To do this, we used multiple probes for cell mechanics including a microfluidic optical stretcher, a microfluidic microcirculation mimetic, and real-time deformability cytometry. We found that nonadherent blood cells, cells arrested in mitosis, and naturally adherent cells brought into suspension, stiffen and become more solidlike upon myosin inhibition across multiple timescales (milliseconds to minutes). Our results hold across several pharmacological and genetic perturbations targeting myosin. Our findings suggest that myosin II activity contributes to increased whole-cell compliance and fluidity. This finding is contrary to what has been reported for cells attached to a substrate, which stiffen via active myosin driven prestress. Our results establish the importance of myosin II as an active component in modulating suspended cell mechanics, with a functional role distinctly different from that for substrate-adhered cells. PMID:25902426

  20. The effect of rabbit antithymocyte globulin on human mesenchymal stem cells.

    PubMed

    Franquesa, Marcella; Baan, Carla C; Korevaar, Sander S; Engela, Anja U; Roemeling-van Rhijn, Marieke; Weimar, Willem; Betjes, Michiel G H; Grinyo, Josep M; Hoogduijn, Martin J

    2013-06-01

    Mesenchymal stem cells (MSCs) possess immunomodulatory properties which are of key interest for their application in autoimmunity and transplantation. In transplantation, administration of MSCs has shown promising results in preclinical models and has recently moved to clinical trials. Therefore, it is important to study the interactions between MSCs and immunosuppressive drugs currently used in transplantation. We aimed to analyze the effect of rabbit antithymocyte globulin (rATG) MSCs. MSCs were obtained from perirenal fat of kidney donors and exposed to ranging doses of rATG (Thymoglobulin(®) , Genzyme; 0.5-100 μg/ml). Binding of rATG, effects on viability and susceptibility to be killed by cytotoxic lymphocytes as well as effects on their immunosuppressive potential of MSCs were tested. rATG binds dose-dependently to MSCs. This binding was associated with slightly impaired viability after 48 and 72 h when compared with nonexposed MSCs. In contrast to nontreated MSCs, rATG preexposed MSCs were susceptible to be lysed by cytokine-activated CD8(+) cytotoxic cells and NKT cells. The capacity of MSCs to suppress the proliferation of anti-CD3/CD28 activated CD4 and CD8 T cells were reduced by the presence of rATG in the culture. rATG reduces the viability and antiproliferative capacity of MSCs in a dose-dependent manner and converts them into targets for CD8 T cells and NKT cell lysis. PMID:23682671

  1. Natural killer cell activity during measles.

    PubMed Central

    Griffin, D E; Ward, B J; Jauregui, E; Johnson, R T; Vaisberg, A

    1990-01-01

    Natural killer cells are postulated to play an important role in host anti-viral defences. We measured natural killer cell activity in 30 individuals with acute measles (73 +/- 21 lytic units (LU)/10(7) cells) and 16 individuals with other infectious diseases (149 +/- 95 LU) and found it reduced compared with values for adults (375 +/- 70 LU; P less than 0.001) or children (300 +/- 73 LU, P less than 0.01) without infection. Reduced natural killer cell activity was found in measles patients with (84 +/- 30 LU) and without (55 +/- 18 LU) complications and was present for at least 3 weeks after the onset of the rash. Activity was increased by in vitro exposure of cells to interleukin-2. Depressed natural killer cell activity parallels in time the suppression of other parameters of cell-mediated immunity that occurs during measles. PMID:1696863

  2. Cell death sensitization of leukemia cells by opioid receptor activation

    PubMed Central

    Friesen, Claudia; Roscher, Mareike; Hormann, Inis; Fichtner, Iduna; Alt, Andreas; Hilger, Ralf A.; Debatin, Klaus-Michael; Miltner, Erich

    2013-01-01

    Cyclic AMP (cAMP) regulates a number of cellular processes and modulates cell death induction. cAMP levels are altered upon stimulation of specific G-protein-coupled receptors inhibiting or activating adenylyl cyclases. Opioid receptor stimulation can activate inhibitory Gi-proteins which in turn block adenylyl cyclase activity reducing cAMP. Opioids such as D,L-methadone induce cell death in leukemia cells. However, the mechanism how opioids trigger apoptosis and activate caspases in leukemia cells is not understood. In this study, we demonstrate that downregulation of cAMP induced by opioid receptor activation using the opioid D,L-methadone kills and sensitizes leukemia cells for doxorubicin treatment. Enhancing cAMP levels by blocking opioid-receptor signaling strongly reduced D,L-methadone-induced apoptosis, caspase activation and doxorubicin-sensitivity. Induction of cell death in leukemia cells by activation of opioid receptors using the opioid D,L-methadone depends on critical levels of opioid receptor expression on the cell surface. Doxorubicin increased opioid receptor expression in leukemia cells. In addition, the opioid D,L-methadone increased doxorubicin uptake and decreased doxorubicin efflux in leukemia cells, suggesting that the opioid D,L-methadone as well as doxorubicin mutually increase their cytotoxic potential. Furthermore, we found that opioid receptor activation using D,L-methadone alone or in addition to doxorubicin inhibits tumor growth significantly in vivo. These results demonstrate that opioid receptor activation via triggering the downregulation of cAMP induces apoptosis, activates caspases and sensitizes leukemia cells for doxorubicin treatment. Hence, opioid receptor activation seems to be a promising strategy to improve anticancer therapies. PMID:23633472

  3. Stem cell tracking with optically active nanoparticles

    PubMed Central

    Gao, Yu; Cui, Yan; Chan, Jerry KY; Xu, Chenjie

    2013-01-01

    Stem-cell-based therapies hold promise and potential to address many unmet clinical needs. Cell tracking with modern imaging modalities offers insight into the underlying biological process of the stem-cell-based therapies, with the goal to reveal cell survival, migration, homing, engraftment, differentiation, and functions. Adaptability, sensitivity, resolution, and non-invasiveness have contributed to the longstanding use of optical imaging for stem cell tracking and analysis. To identify transplanted stem cells from the host tissue, optically active probes are usually used to label stem cells before the administration. In comparison to the traditional fluorescent probes like fluorescent proteins and dyes, nanoparticle-based probes are advantageous in terms of the photo-stabilities and minimal changes to the cell phenotype. The main focus here is to overview the recent development of optically active nanoparticles for stem cells tracking. The related optical imaging modalities include fluorescence imaging, photoacoustic imaging, Raman and surface enhanced Raman spectroscopy imaging. PMID:23638335

  4. Mitochondrial ROS fire up T cell activation.

    PubMed

    Murphy, Michael P; Siegel, Richard M

    2013-02-21

    Metabolic reprogramming has emerged as an important feature of immune cell activation. Two new studies, including Sena et al. (2013) in this issue of Immunity, identify mitochondrial reactive oxygen species (ROS) arising from metabolic reprogramming as signaling molecules in T cell activation. PMID:23438817

  5. Generation of Novel Traj18-Deficient Mice Lacking Vα14 Natural Killer T Cells with an Undisturbed T Cell Receptor α-Chain Repertoire

    PubMed Central

    Dashtsoodol, Nyambayar; Shigeura, Tomokuni; Ozawa, Ritsuko; Harada, Michishige; Kojo, Satoshi; Watanabe, Takashi; Koseki, Haruhiko; Nakayama, Manabu; Ohara, Osamu; Taniguchi, Masaru

    2016-01-01

    Invariant Vα14 natural killer T (NKT) cells, characterized by the expression of a single invariant T cell receptor (TCR) α chain encoded by rearranged Trav11 (Vα14)-Traj18 (Jα18) gene segments in mice, and TRAV10 (Vα24)-TRAJ18 (Jα18) in humans, mediate adjuvant effects to activate various effector cell types in both innate and adaptive immune systems that facilitates the potent antitumor effects. It was recently reported that the Jα18-deficient mouse described by our group in 1997 harbors perturbed TCRα repertoire, which raised concerns regarding the validity of some of the experimental conclusions that have been made using this mouse line. To resolve this concern, we generated a novel Traj18-deficient mouse line by specifically targeting the Traj18 gene segment using Cre-Lox approach. Here we showed the newly generated Traj18-deficient mouse has, apart from the absence of Traj18, an undisturbed TCRα chain repertoire by using next generation sequencing and by detecting normal generation of Vα19Jα33 expressing mucosal associated invariant T cells, whose development was abrogated in the originally described Jα18-KO mice. We also demonstrated here the definitive requirement for NKT cells in the protection against tumors and their potent adjuvant effects on antigen-specific CD8 T cells. PMID:27064277

  6. Activity-driven fluctuations in living cells

    NASA Astrophysics Data System (ADS)

    Fodor, É.; Guo, M.; Gov, N. S.; Visco, P.; Weitz, D. A.; van Wijland, F.

    2015-05-01

    We propose a model for the dynamics of a probe embedded in a living cell, where both thermal fluctuations and nonequilibrium activity coexist. The model is based on a confining harmonic potential describing the elastic cytoskeletal matrix, which undergoes random active hops as a result of the nonequilibrium rearrangements within the cell. We describe the probe's statistics and we bring forth quantities affected by the nonequilibrium activity. We find an excellent agreement between the predictions of our model and experimental results for tracers inside living cells. Finally, we exploit our model to arrive at quantitative predictions for the parameters characterizing nonequilibrium activity, such as the typical time scale of the activity and the amplitude of the active fluctuations.

  7. The Role of Adenosine Signaling in Sickle Cell Therapeutics

    PubMed Central

    Field, Joshua J.; Nathan, David G.; Linden, Joel

    2014-01-01

    Recent data suggest a role for adenosine signaling in the pathogenesis of sickle cell disease (SCD). Signaling through the adenosine A2A receptor (A2AR) has demonstrated beneficial effects in SCD. Activation of A2ARs decreases inflammation in mice and patients with SCD largely by blocking activation of invariant NKT cells. Decreased inflammation may reduce the severity of vaso-occlusive crises. In contrast, adenosine signaling through the A2B receptor (A2BR) may be detrimental for patients with SCD. Priapism and the formation of sickle erythrocytes may be a consequence of A2BR activation on corpus cavernosal cells and erythrocytes, respectively. Whether adenosine signaling predominantly occurs through A2ARs or A2BRs may depend on differing levels of adenosine and disease state (steady state versus crisis). There may be opportunities to develop novel therapeutic approaches targeting A2ARs and/or A2BRs for patients with SCD. PMID:24589267

  8. Type I natural killer T cells: naturally born for fighting

    PubMed Central

    Tan, Jin-quan; Xiao, Wei; Wang, Lan; He, Yu-ling

    2010-01-01

    Type І natural killer T cells (NKT cells), a subset of CD1d-restricted T cells with invariant Vαβ TCR, are characterized by prompt production of large amounts of Th1 and/or Th2 cytokines upon primary stimulation through the TCR complex. The rapid release of cytokines implies that type І NKT cells may play a critical role in modulating the upcoming immune responses, such as anti-tumor response, protection against infection, and autoimmunity. As a bridge between innate and adaptive immunity, type І NKT cells differentiate and mature upon stimulations to achieve and maintain a homeostasis. Orchestrating with other arms of adaptive immunity, type І NKT cells show strong cytotoxic effects in response to various tumors in a direct and/or indirect manner(s). This review will focus primarily on type І NKT cell development, homeostasis, and effector functions, especially in anti-tumor immunity, and followed by their potential applications in treatment of cancers. PMID:20694020

  9. The extract of Japanese soybean, Kurosengoku activates the production of IL-12 and IFN-γ by DC or NK1.1(+) cells in a TLR4- and TLR2-dependent manner.

    PubMed

    Tanaka, Sachi; Koizumi, Shin-ichi; Makiuchi, Naoko; Aoyagi, Yuka; Quivy, Emi; Mitamura, Rieko; Kano, Tsutomu; Wakita, Daiko; Chamoto, Kenji; Kitamura, Hidemitsu; Nishimura, Takashi

    2011-01-01

    During the search for immuno-improving foods, we found that a variety of the Japanese soybean, Glycine max cv. Kurosengoku (Kurosengoku), which activated Type-1 immunity in a Toll-like receptor (TLR)4- and TLR2-dependent manner. Namely, the extract of Kurosengoku first caused production of IL-12 from DC and sequentially induced IFN-γ production by NK1.1(+) NK cells and NKT cells. The IFN-γ production was significantly blocked by neutralizing mAb against IL-12 or TLR4- and TLR2-deficient condition, indicating that TLR4- and TLR2-dependent activation of DC to produce IL-12 was essential for the production of IFN-γ from spleen cells by Kurosengoku. Moreover, the extract of Kurosengoku also enhanced production of IFN-γ from human PBMC by co-stimulation with anti-CD3 mAb in a TLR2- and TLR4-dependent manner. Thus, our findings strongly suggest that Kurosengoku might a novel immuno-improving food, which would be a useful tool for preventing the tip of immune balance in developed countries. PMID:20971456

  10. Kinetic discrimination in T-cell activation.

    PubMed Central

    Rabinowitz, J D; Beeson, C; Lyons, D S; Davis, M M; McConnell, H M

    1996-01-01

    We propose a quantitative model for T-cell activation in which the rate of dissociation of ligand from T-cell receptors determines the agonist and antagonist properties of the ligand. The ligands are molecular complexes between antigenic peptides and proteins of the major histocompatibility complex on the surfaces of antigen-presenting cells. Binding of ligand to receptor triggers a series of biochemical reactions in the T cell. If the ligand dissociates after these reactions are complete, the T cell receives a positive activation signal. However, dissociation of ligand after completion of the first reaction but prior to generation of the final products results in partial T-cell activation, which acts to suppress a positive response. Such a negative signal is brought about by T-cell ligands containing the variants of antigenic peptides referred to as T-cell receptor antagonists. Results of recent experiments with altered peptide ligands compare favorably with T-cell responses predicted by this model. PMID:8643643

  11. Lipolytic activity in adipocyte cell fractions.

    PubMed

    Oschry, Y; Shapiro, B

    1980-05-28

    Adipocytes release only negligible amounts of free fatty acids unless stimulated, but reveal considerable lipolytic activity when homogenized. Epinephrine treatment of the cells caused only a 20-40% increase in the activity of infranatants of homogenates while raising the activity associated with the fat layer up to 10-fold. Full activity (i.e. that of intact-activated cells) could be revealed by epinephrine treatment of the homogenate as well as by sonication of the fat layer in buffer. The combination of both treatments did not yield higher activities. The fat cake contains the bulk of the potential activities which are only realized when dispersed in the aqueous phase by sonication, or upon hormone activation of the whole homogenate. Increase in activity could also be obtained by removal of most of the lipid from the fat layer by extraction with petroleum ether. Re-introduction of extracted lipid inhibited lipolysis. The active enzyme could be separated by flotation at 1.12 specific gravity. The data suggest that the lack of activity in the intact non-stimulated cell may be due to the lack of availability of the aqueous phase to the enzyme. PMID:7378439

  12. Nasal T cell lymphoma: a rare entity.

    PubMed

    Kazi, Maliha; Ikram, Mubasher; Junaid, Montasir

    2014-03-01

    Nasal type of Natural Killer (NK)/T cell lymphoma manifests in the nasal cavity. Approximately 95% of them are associated with EBV(Ebstein Barr Virus) with a strong predilection for the Asian population. It has certain systemic and localized symptoms which aid in diagnosis of the condition. However, the histological criteria is pivotal in confirming the diagnosis as well as aiding in confirming the association of EBV. Nasal type of NK/T cell lymphoma has a guarded prognosis. Treatment plan include radiotherapy with concurrent chemotherapy. Despite all this, the 5-year survival rate ranges from 15-75%. A 35 years old male presented with an ulcerative nasal lesion. Diagnosed as nasal type of NK/T cell lymphoma via a tissue biopsy, it was managed by chemo-radiotherapy leading to complete resolution of symptoms and disease free on his follow-up 6 months later. PMID:24718007

  13. Lymphatic endothelial cells actively regulate prostate cancer cell invasion.

    PubMed

    Shah, Tariq; Wildes, Flonne; Kakkad, Samata; Artemov, Dmitri; Bhujwalla, Zaver M

    2016-07-01

    Lymphatic vessels serve as the primary route for metastatic spread to lymph nodes. However, it is not clear how interactions between cancer cells and lymphatic endothelial cells (LECs), especially within hypoxic microenvironments, affect the invasion of cancer cells. Here, using an MR compatible cell perfusion assay, we investigated the role of LEC-prostate cancer (PCa) cell interaction in the invasion and degradation of the extracellular matrix (ECM) by two human PCa cell lines, PC-3 and DU-145, under normoxia and hypoxia, and determined the metabolic changes that occurred under these conditions. We observed a significant increase in the invasion of ECM by invasive PC-3 cells, but not poorly invasive DU-145 cells when human dermal lymphatic microvascular endothelial cells (HMVEC-dlys) were present. Enhanced degradation of ECM by PC-3 cells in the presence of HMVEC-dlys identified interactions between HMVEC-dlys and PCa cells influencing cancer cell invasion. The enhanced ECM degradation was partly attributed to increased MMP-9 enzymatic activity in PC-3 cells when HMVEC-dlys were in close proximity. Significantly higher uPAR and MMP-9 expression levels observed in PC-3 cells compared to DU-145 cells may be one mechanism for increased invasion and degradation of matrigel by these cells irrespective of the presence of HMVEC-dlys. Hypoxia significantly decreased invasion by PC-3 cells, but this decrease was significantly attenuated when HMVEC-dlys were present. Significantly higher phosphocholine was observed in invasive PC-3 cells, while higher glycerophosphocholine was observed in DU-145 cells. These metabolites were not altered in the presence of HMVEC-dlys. Significantly increased lipid levels and lipid droplets were observed in PC-3 and DU-145 cells under hypoxia reflecting an adaptive survival response to oxidative stress. These results suggest that in vivo, invasive cells in or near lymphatic endothelial cells are likely to be more invasive and degrade the ECM

  14. Lysophospholipid presentation by CD1d and recognition by a human Natural Killer T-cell receptor

    PubMed Central

    López-Sagaseta, Jacinto; Sibener, Leah V; Kung, Jennifer E; Gumperz, Jenny; Adams, Erin J

    2012-01-01

    Invariant Natural Killer T (iNKT) cells use highly restricted αβ T cell receptors (TCRs) to probe the repertoire of lipids presented by CD1d molecules. Here, we describe our studies of lysophosphatidylcholine (LPC) presentation by human CD1d and its recognition by a native, LPC-specific iNKT TCR. Human CD1d presenting LPC adopts an altered conformation from that of CD1d presenting glycolipid antigens, with a shifted α1 helix resulting in an open A' pocket. Binding of the iNKT TCR requires a 7-Å displacement of the LPC headgroup but stabilizes the CD1d–LPC complex in a closed conformation. The iNKT TCR CDR loop footprint on CD1d–LPC is anchored by the conserved positioning of the CDR3α loop, whereas the remaining CDR loops are shifted, due in part to amino-acid differences in the CDR3β and Jβ segment used by this iNKT TCR. These findings provide insight into how lysophospholipids are presented by human CD1d molecules and how this complex is recognized by some, but not all, human iNKT cells. PMID:22395072

  15. Lysophospholipid presentation by CD1d and recognition by a human Natural Killer T-cell receptor

    SciTech Connect

    López-Sagaseta, Jacinto; Sibener, Leah V.; Kung, Jennifer E.; Gumperz, Jenny; Adams, Erin J.

    2014-10-02

    Invariant Natural Killer T (iNKT) cells use highly restricted {alpha}{beta} T cell receptors (TCRs) to probe the repertoire of lipids presented by CD1d molecules. Here, we describe our studies of lysophosphatidylcholine (LPC) presentation by human CD1d and its recognition by a native, LPC-specific iNKT TCR. Human CD1d presenting LPC adopts an altered conformation from that of CD1d presenting glycolipid antigens, with a shifted {alpha}1 helix resulting in an open A pocket. Binding of the iNKT TCR requires a 7-{angstrom} displacement of the LPC headgroup but stabilizes the CD1d-LPC complex in a closed conformation. The iNKT TCR CDR loop footprint on CD1d-LPC is anchored by the conserved positioning of the CDR3{alpha} loop, whereas the remaining CDR loops are shifted, due in part to amino-acid differences in the CDR3{beta} and J{beta} segment used by this iNKT TCR. These findings provide insight into how lysophospholipids are presented by human CD1d molecules and how this complex is recognized by some, but not all, human iNKT cells.

  16. Activation of intraislet lymphoid cells causes destruction of islet cells.

    PubMed Central

    Lacy, P. E.; Finke, E. H.

    1991-01-01

    In vitro culture of rat islets at 24 degrees C for 7 days in tissue culture medium CMRL 1066 almost completely eliminated lymphoid cells from the islets. Immunostaining of the islets with monoclonal antibody OX4 for demonstration of class II major histocompatibility complex (MHC)-expressing cells revealed a decrease from 13.1 +/- 0.6 positive cells per islet on day 0 to 0.7 +/- 0.1 cells per islet on day 7. A comparable decrease was found using OX1 for demonstration of all leukocytes. In contrast, culture of rat islets at 24 degrees C for 7 days with tissue culture Roswell Park Memorial Institute (RPMI) 1640 medium was not as effective in eliminating lymphoid cells as in medium CMRL 1066 (3.0 +/- 0.2 class II MHC positive cells per islet at 7 days). Effective elimination of intraislet lymphoid cells apparently is due to the combined effect of low temperature culture and the tissue culture medium CMRL-1066. The second goal of the study was to determine whether the destructive effect of interferon gamma (IFN-gamma) on rat islets in culture was due to intraislet lymphoid cells. In vitro culture of rat islets with IFN-gamma (1000 units/ml) at 37 degrees C caused almost complete destruction of the islets at 7 days. If intraislet lymphoid cells were eliminated from the islets by in vitro culture at 24 degrees C followed by exposure to IFN-gamma (1000 units/ml) for 7 days at 37 degrees C, then IFN-gamma did not cause destruction of the islets and transplants of the treated islets produced normoglycemia in diabetic recipient mice. These findings indicate that intraislet lymphoid cells are responsible for destruction of islet cells when these cells (presumably macrophages) are activated by IFN-gamma. Intraislet lymphoid cells may play a significant role in destroying islet cells in autoimmune diabetes. Images Figure 1 Figure 2 PMID:1902627

  17. Protrusive Activity Guides Changes in Cell-Cell Tension during Epithelial Cell Scattering

    PubMed Central

    Maruthamuthu, Venkat; Gardel, Margaret L.

    2014-01-01

    Knowing how epithelial cells regulate cell-matrix and cell-cell adhesions is essential to understand key events in morphogenesis as well as pathological events such as metastasis. During epithelial cell scattering, epithelial cell islands rupture their cell-cell contacts and migrate away as single cells on the extracellular matrix (ECM) within hours of growth factor stimulation, even as adhesion molecules such as E-cadherin are present at the cell-cell contact. How the stability of cell-cell contacts is modulated to effect such morphological transitions is still unclear. Here, we report that in the absence of ECM, E-cadherin adhesions continue to sustain substantial cell-generated forces upon hepatocyte growth factor (HGF) stimulation, consistent with undiminished adhesion strength. In the presence of focal adhesions, constraints that preclude the spreading and movement of cells at free island edges also prevent HGF-mediated contact rupture. To explore the role of cell motion and cell-cell contact rupture, we examine the biophysical changes that occur during the scattering of cell pairs. We show that the direction of cell movement with respect to the cell-cell contact is correlated with changes in the average intercellular force as well as the initial direction of cell-cell contact rupture. Our results suggest an important role for protrusive activity resulting in cell displacement and force redistribution in guiding cell-cell contact rupture during scattering. PMID:25099795

  18. Activation of radiosensitizers by hypoxic cells.

    PubMed Central

    Olive, P. L.; Durand, R. E.

    1978-01-01

    Hypoxic cells can metabolize nitroheterocyclic compounds to produce toxic intermediates capable of affecting the survival of neighbouring oxygenated cells. Mutagenesis experiments with E. coli WP-2 343 (deficient in nitroreductase) indicated that reduction of nitroheterocyclics outside bacteria causes killing and mutations within bacteria, presumably due to the transfer of the "active" specie (s). Using animal tissue slices to reduce nitrofurans, cultured L-929 cells incubated under aerobic conditions were far more sensitive to the toxic and DNA damaging effects of these drugs. Transfer of the active species also occurs in a tissue-like environment in multicell spheroids where the presence of a hypoxic central core served to convert the nitroheterocyclics to intermediates which also damaged the neighbouring oxygenated cells. PMID:354676

  19. Polyclonal B cell activation in ankylosing spondylitis.

    PubMed Central

    Barbieri, P; Olivieri, I; Benedettini, G; Marelli, P; Ciompi, M L; Pasero, G; Campa, M

    1990-01-01

    The peripheral blood lymphocyte response of patients with ankylosing spondylitis (AS) to several polyclonal B cell activators was investigated. No differences were found in the reactivity to pokeweed mitogen and protein A between patients and controls; in contrast, the peripheral blood lymphocyte response to Staphylococcus aureus strain Cowan I (SAC) was significantly higher in patients with AS than in controls. This responsiveness was not influenced either by the presence of the HLA-B27 antigen or by environmental factors or associated diseases, and it was higher in patients with active AS than in those with inactive disease. The percentage of circulating B cells was normal. The responses to T cell mitogens and the percentages of T cell subpopulations were similar in patients and in controls. The peripheral blood lymphocyte hyperactivity of patients with AS to SAC was associated with an increased in vitro production of immunoglobulins. PMID:2383063

  20. (+)-Catechin attenuates activation of hepatic stellate cells.

    PubMed

    Bragança de Moraes, Cristina Machado; Bitencourt, Shanna; de Mesquita, Fernanda Cristina; Mello, Denizar; de Oliveira, Leticia Paranhos; da Silva, Gabriela Viegas; Lorini, Vinicius; Caberlon, Eduardo; de Souza Basso, Bruno; Schmid, Julia; Ferreira, Gabriela Acevedo; de Oliveira, Jarbas Rodrigues

    2014-04-01

    (+)-Catechin is a type of catechin present in large amounts in açaí fruits and cocoa seeds. Besides its antioxidant and anti-inflammatory activities, little is known about its effects in the liver, especially during hepatic fibrosis. We report here the effects of (+)-catechin on hepatic stellate cells. (+)-Catechin induced quiescent phenotype in GRX cells, along with an increase in lipid droplets. Proliferator-activated receptor γ mRNA expression was upregulated, whereas type I collagen mRNA expression was downregulated. Pro-inflammatory cytokines were not influenced by (+)-catechin, whereas the levels of interleukin 10 were significantly increased. The data provide evidence that (+)-catechin can reduce hepatic stellate cell activation. PMID:24353036

  1. Entangled active matter: From cells to ants

    NASA Astrophysics Data System (ADS)

    Hu, D. L.; Phonekeo, S.; Altshuler, E.; Brochard-Wyart, F.

    2016-07-01

    Both cells and ants belong to the broad field of active matter, a novel class of non-equilibrium materials composed of many interacting units that individually consume energy and collectively generate motion or mechanical stresses. However cells and ants differ from fish and birds in that they can support static loads. This is because cells and ants can be entangled, so that individual units are bound by transient links. Entanglement gives cells and ants a set of remarkable properties usually not found together, such as the ability to flow like a fluid, spring back like an elastic solid, and self-heal. In this review, we present the biology, mechanics and dynamics of both entangled cells and ants. We apply concepts from soft matter physics and wetting to characterize these systems as well as to point out their differences, which arise from their differences in size. We hope that our viewpoints will spur further investigations into cells and ants as active materials, and inspire the fabrication of synthetic active matter.

  2. Imaging CREB Activation in Living Cells*

    PubMed Central

    Friedrich, Michael W.; Aramuni, Gayane; Mank, Marco; Mackinnon, Jonathan A. G.; Griesbeck, Oliver

    2010-01-01

    The Ca2+- and cAMP-responsive element-binding protein (CREB) and the related ATF-1 and CREM are stimulus-inducible transcription factors that link certain forms of cellular activity to changes in gene expression. They are attributed to complex integrative activation characteristics, but current biochemical technology does not allow dynamic imaging of CREB activation in single cells. Using fluorescence resonance energy transfer between mutants of green fluorescent protein we here develop a signal-optimized genetically encoded indicator that enables imaging activation of CREB due to phosphorylation of the critical serine 133. The indicator of CREB activation due to phosphorylation (ICAP) was used to investigate the role of the scaffold and anchoring protein AKAP79/150 in regulating signal pathways converging on CREB. We show that disruption of AKAP79/150-mediated protein kinase A anchoring or knock-down of AKAP150 dramatically reduces the ability of protein kinase A to activate CREB. In contrast, AKAP79/150 regulation of CREB via L-type channels may only have minor importance. ICAP allows dynamic and reversible imaging in living cells and may become useful in studying molecular components and cell-type specificity of activity-dependent gene expression. PMID:20484048

  3. Critical telomerase activity for uncontrolled cell growth.

    PubMed

    Wesch, Neil L; Burlock, Laura J; Gooding, Robert J

    2016-01-01

    The lengths of the telomere regions of chromosomes in a population of cells are modelled using a chemical master equation formalism, from which the evolution of the average number of cells of each telomere length is extracted. In particular, the role of the telomere-elongating enzyme telomerase on these dynamics is investigated. We show that for biologically relevant rates of cell birth and death, one finds a critical rate, R crit, of telomerase activity such that the total number of cells diverges. Further, R crit is similar in magnitude to the rates of mitosis and cell death. The possible relationship of this result to replicative immortality and its associated hallmark of cancer is discussed. PMID:27500377

  4. Critical telomerase activity for uncontrolled cell growth

    NASA Astrophysics Data System (ADS)

    Wesch, Neil L.; Burlock, Laura J.; Gooding, Robert J.

    2016-08-01

    The lengths of the telomere regions of chromosomes in a population of cells are modelled using a chemical master equation formalism, from which the evolution of the average number of cells of each telomere length is extracted. In particular, the role of the telomere-elongating enzyme telomerase on these dynamics is investigated. We show that for biologically relevant rates of cell birth and death, one finds a critical rate, R crit, of telomerase activity such that the total number of cells diverges. Further, R crit is similar in magnitude to the rates of mitosis and cell death. The possible relationship of this result to replicative immortality and its associated hallmark of cancer is discussed.

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

    PubMed Central

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

    2016-01-01

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

  6. Activated mast cells promote differentiation of B cells into effector cells

    PubMed Central

    Palm, Anna-Karin E.; Garcia-Faroldi, Gianni; Lundberg, Marcus; Pejler, Gunnar; Kleinau, Sandra

    2016-01-01

    Based on the known accumulation of mast cells (MCs) in B cell-dependent inflammatory diseases, including rheumatoid arthritis, we hypothesized that MCs directly modulate B cells. We show here that degranulated, and to a lesser extent naïve or IgE-sensitized, MCs activate both naïve and B cell receptor-activated B cells. This was shown by increased proliferation, blast formation, and expression of CD19, MHC class II and CD86 in the B cells. Further, MCs stimulated the secretion of IgM and IgG in IgM+ B cells, indicating that MCs can induce class-switch recombination in B cells. We also show that coculture of MCs with B cells promotes surface expression of L-selectin, a homing receptor, on the B cells. The effects of MCs on B cells were partly dependent on cell-cell contact and both follicular and marginal zone B cells could be activated by MCs. Our findings suggest that degranulated MCs support optimal activation of B cells, a finding that is in line with in vivo studies showing that MCs frequently degranulate in the context of B-cell driven pathologies such as arthritis. Together, our findings show that MCs have the capacity to differentiate B cells to effector cells. PMID:26847186

  7. Structural insight into MR1-mediated recognition of the mucosal associated invariant T cell receptor

    PubMed Central

    Reantragoon, Rangsima; Kjer-Nielsen, Lars; Patel, Onisha; Chen, Zhenjun; Illing, Patricia T.; Bhati, Mugdha; Kostenko, Lyudmila; Bharadwaj, Mandvi; Meehan, Bronwyn; Hansen, Ted H.; Godfrey, Dale I.

    2012-01-01

    Mucosal-associated invariant T (MAIT) cells express a semiinvariant αβ T cell receptor (TCR) that binds MHC class I–like molecule (MR1). However, the molecular basis for MAIT TCR recognition by MR1 is unknown. In this study, we present the crystal structure of a human Vα7.2Jα33-Vβ2 MAIT TCR. Mutagenesis revealed highly conserved requirements for the MAIT TCR–MR1 interaction across different human MAIT TCRs stimulated by distinct microbial sources. Individual residues within the MAIT TCR β chain were dispensable for the interaction with MR1, whereas the invariant MAIT TCR α chain controlled specificity through a small number of residues, which are conserved across species and located within the Vα-Jα regions. Mutagenesis of MR1 showed that only two residues, which were centrally positioned and on opposing sides of the antigen-binding cleft of MR1, were essential for MAIT cell activation. The mutagenesis data are consistent with a centrally located MAIT TCR–MR1 docking that was dominated by the α chain of the MAIT TCR. This candidate docking mode contrasts with that of the NKT TCR–CD1d-antigen interaction, in which both the α and β chain of the NKT TCR is required for ligation above the F′-pocket of CD1d. PMID:22412157

  8. Candida albicans up-regulates the Fas-L expression in liver Natural Killer and Natural Killer T cells.

    PubMed

    Renna, María Sol; Figueredo, Carlos Mauricio; Rodríguez-Galán, María Cecilia; Icely, Paula Alejandra; Cejas, Hugo; Cano, Roxana; Correa, Silvia Graciela; Sotomayor, Claudia Elena

    2015-11-01

    After Candida albicans arrival to the liver, the local production of proinflammatory cytokines and the expanded intrahepatic lymphocytes (IHL) can be either beneficial or detrimental to the host. Herein we explored the balance between protective inflammatory reaction and liver damage, focusing our study on the contribution of TNF-α and Fas-Fas-L pathways in the hepatocellular apoptosis associated to C. albicans infection. A robust tissue reaction and a progressive increase of IL-1β, IL-6 and TNF-α were observed in infected animals. Blocking the biological activity of TNF-α did not modify the number of apoptotic cells observed in C. albicans infected animals. Fas-L molecule was up regulated on purified hepatic mononuclear cells and its expression progressed with the infection. In the IHL compartment, the absolute number of Fas-L+ NK and NKT cells increased on days 1 and 3 of the infection. C. albicans was also able to up regulate Fas-L expression in normal liver NK and NKT cells after in vitro contact. The innate receptor TLR2 was involved in this phenomenon. In the interplay between host factors and evasion strategies exploited by pathogens, the mechanism supported here could represent an additional way that allows this fungus to circumvent protective immune responses in the liver. PMID:26101139

  9. Active mechanics and geometry of adherent cells and cell colonies

    NASA Astrophysics Data System (ADS)

    Banerjee, Shiladitya

    2014-03-01

    Measurements of traction stresses exerted by adherent cells or cell colonies on elastic substrates have yielded new insight on how the mechanical and geometrical properties of the substrate regulate cellular force distribution, mechanical energy, spreading, morphology or stress ber architecture. We have developed a generic mechanical model of adherent cells as an active contractile gel mechanically coupled to an elastic substrate and to neighboring cells in a tissue. The contractile gel model accurately predicts the distribution of cellular and traction stresses as observed in single cell experiments, and captures the dependence of cell shape, traction stresses and stress ber polarization on the substrate's mechanical and geometrical properties. The model further predicts that the total strain energy of an adherent cell is solely regulated by its spread area, in agreement with recent experiments on micropatterned substrates with controlled geometry. When used to describe the behavior of colonies of adherent epithelial cells, the model demonstrates the crucial role of the mechanical cross-talk between intercellular and extracellular adhesion in regulating traction force distribution. Strong intercellular mechanical coupling organizes traction forces to the colony periphery, whereas weaker intercellular coupling leads to the build up of traction stresses at intercellular junctions. Furthermore, in agreement with experiments on large cohesive keratinocyte colonies, the model predicts a linear scaling of traction forces with the colony size. This scaling suggests the emergence of an effective surface tension as a scale-free material property of the adherent tissue, originating from actomyosin contractility.

  10. Invariant Natural Killer T cells in children with Eosinophilic Esophagitis

    PubMed Central

    Jyonouchi, Soma; Smith, Cara Lea; Saretta, Francesca; Abraham, Valsamma; Ruymann, Kathryn R; Modayur-Chandramouleeswaran, Prasanna; Wang, Mei-Lun; Spergel, Jonathan M.; Cianferoni, Antonella

    2013-01-01

    Background Eosinophilic esophagitis (EoE) is an atopic disease characterized by eosinophilic inflammation in which dietary antigens (in particular, milk) play a major role. EoE is most likely a mixed IgE and non-IgE food-mediated reaction in which over-expression of Th2 cytokines, particularly IL-13, play a major role; however, the cells responsible for IL-13 over-expression remain elusive. Th2-cytokines are secreted following the ligation of invariant natural killer T cell receptors to sphingolipids (SL). Sphingolipids (SL) are presented via the CD1d molecule on the INKT cell surface. Cow’s milk-derived SL has been shown to activate iNKTs from children with IgE-mediated food allergies to milk (FA-MA) to produce Th2 cytokines. The role of iNKTs and milk-SL in EoE pathogenesis is currently unknown. Objective To investigate the role of iNKTs and milk-SL in EoE. Methods Peripheral blood mononuclear cells (PBMCs) from 10 children with active EoE (EoE-A), 10 children with controlled EoE (EoE-C), and 16 healthy controls (Non-EoE) were measured ex-vivo and then incubated with α-galactosylceramide (αGal) and milk-SL. INKTs from peripheral blood (PB) and esophageal biopsies were studied. Results EoE-A-children had significantly fewer peripheral blood iNKTs with a greater Th2-response to αGal and milk-SM compared to iNKTs of EoE-C and Non-EoE children. Additionally, EoE-A children had increased iNKT levels in esophageal biopsies compared to EoE-C children. Conclusion Milk-SLs are able to activate peripheral blood iNKTs in EoE-A children to produce Th2 cytokines. Additionally, iNKT levels are higher at the site of active esophageal eosinophilic inflammation. Clinical Relevance This study suggests that sphingolipids (SL) contained in milk may drive the development of EoE by promoting an iNKT cell-mediated Th2-type cytokine response that facilitates eosinophil-mediated allergic inflammation. PMID:24118614

  11. Mechanically activated artificial cell by using microfluidics.

    PubMed

    Ho, Kenneth K Y; Lee, Lap Man; Liu, Allen P

    2016-01-01

    All living organisms sense mechanical forces. Engineering mechanosensitive artificial cell through bottom-up in vitro reconstitution offers a way to understand how mixtures of macromolecules assemble and organize into a complex system that responds to forces. We use stable double emulsion droplets (aqueous/oil/aqueous) to prototype mechanosensitive artificial cells. In order to demonstrate mechanosensation in artificial cells, we develop a novel microfluidic device that is capable of trapping double emulsions into designated chambers, followed by compression and aspiration in a parallel manner. The microfluidic device is fabricated using multilayer soft lithography technology, and consists of a control layer and a deformable flow channel. Deflections of the PDMS membrane above the main microfluidic flow channels and trapping chamber array are independently regulated pneumatically by two sets of integrated microfluidic valves. We successfully compress and aspirate the double emulsions, which result in transient increase and permanent decrease in oil thickness, respectively. Finally, we demonstrate the influx of calcium ions as a response of our mechanically activated artificial cell through thinning of oil. The development of a microfluidic device to mechanically activate artificial cells creates new opportunities in force-activated synthetic biology. PMID:27610921

  12. Mechanically activated artificial cell by using microfluidics

    PubMed Central

    Ho, Kenneth K. Y.; Lee, Lap Man; Liu, Allen P.

    2016-01-01

    All living organisms sense mechanical forces. Engineering mechanosensitive artificial cell through bottom-up in vitro reconstitution offers a way to understand how mixtures of macromolecules assemble and organize into a complex system that responds to forces. We use stable double emulsion droplets (aqueous/oil/aqueous) to prototype mechanosensitive artificial cells. In order to demonstrate mechanosensation in artificial cells, we develop a novel microfluidic device that is capable of trapping double emulsions into designated chambers, followed by compression and aspiration in a parallel manner. The microfluidic device is fabricated using multilayer soft lithography technology, and consists of a control layer and a deformable flow channel. Deflections of the PDMS membrane above the main microfluidic flow channels and trapping chamber array are independently regulated pneumatically by two sets of integrated microfluidic valves. We successfully compress and aspirate the double emulsions, which result in transient increase and permanent decrease in oil thickness, respectively. Finally, we demonstrate the influx of calcium ions as a response of our mechanically activated artificial cell through thinning of oil. The development of a microfluidic device to mechanically activate artificial cells creates new opportunities in force-activated synthetic biology. PMID:27610921

  13. Photochemical approaches to T-cell activation

    PubMed Central

    Huse, Morgan

    2010-01-01

    Despite decades of intensive research, T-cell activation has remained mysterious because of both the dizzying diversity of antigen recognition and the speed and comprehensiveness of the T-cell-receptor signalling network. Further progress will require new approaches and reagents that provide added levels of control. Photochemistry allows specific biochemical processes to be controlled with light and is well suited to mechanistic studies in complex cellular environments. In recent years, several laboratories have adopted approaches based on photoreactive peptide-major histocompatibility complex reagents in order to study T-cell activation and function with high precision. Here, I review these efforts and outline future directions for this exciting area of research. PMID:20406301

  14. Epigenetic Changes during Hepatic Stellate Cell Activation

    PubMed Central

    Götze, Silke; Schumacher, Eva C.; Kordes, Claus; Häussinger, Dieter

    2015-01-01

    Background and Aims Hepatic stellate cells (HSC), which can participate in liver regeneration and fibrogenesis, have recently been identified as liver-resident mesenchymal stem cells. During their activation HSC adopt a myofibroblast-like phenotype accompanied by profound changes in the gene expression profile. DNA methylation changes at single genes have been reported during HSC activation and may participate in the regulation of this process, but comprehensive DNA methylation analyses are still missing. The aim of the present study was to elucidate the role of DNA methylation during in vitro activation of HSC. Methods and Results The analysis of DNA methylation changes by antibody-based assays revealed a strong decrease in the global DNA methylation level during culture-induced activation of HSC. To identify genes which may be regulated by DNA methylation, we performed a genome-wide Methyl-MiniSeq EpiQuest sequencing comparing quiescent and early culture-activated HSC. Approximately 400 differentially methylated regions with a methylation change of at least 20% were identified, showing either hypo- or hypermethylation during activation. Further analysis of selected genes for DNA methylation and expression were performed revealing a good correlation between DNA methylation changes and gene expression. Furthermore, global DNA demethylation during HSC activation was investigated by 5-bromo-2-deoxyuridine assay and L-mimosine treatment showing that demethylation was independent of DNA synthesis and thereby excluding a passive DNA demethylation mechanism. Conclusions In summary, in vitro activation of HSC initiated strong DNA methylation changes, which were associated with gene regulation. These results indicate that epigenetic mechanisms are important for the control of early HSC activation. Furthermore, the data show that global DNA demethylation during activation is based on an active DNA demethylation mechanism. PMID:26065684

  15. PLZF confers effector functions to donor T cells that preserve graft-versus-tumor effects while attenuating graft-versus-host-disease

    PubMed Central

    Ghosh, Arnab; Holland, Amanda M.; Dogan, Yildirim; Yim, Nury L.; Rao, Uttam K.; Young, Lauren F.; West, Mallory L.; Singer, Natalie V.; Lee, Hae; Na, Il-Kang; Tsai, Jennifer J.; Jenq, Robert R.; Penack, Olaf; Hanash, Alan M.; Lezcano, Cecilia; Murphy, George; Liu, Chen; Sadelain, Michel; Sauer, Martin G.; Sant’Angelo, Derek; van den Brink, Marcel R.M.

    2013-01-01

    Efforts to limit graft-versus-host disease (GVHD) mediated by alloreactive donor T cells after allogeneic bone marrow transplantation (allo-BMT) are limited by a concomitant decrease in graft-versus-tumor (GVT) activity and increased possibilities of tumor relapse. Using a novel approach, we adoptively transferred conventional T cells expressing the transcription factor promyelocytic leukemia zinc finger (PLZF), which confers effector properties resembling invariant natural killer T cells (iNKT cells), such as copious production of cytokines under suboptimal stimulation. PLZF expression in T cell allografts attenuates expansion of alloreactive T cells, leading to lower GVHD. Intact alloreactivity-driven antitumor cytokine responses result in preserved GVT effects leading to improved survival. Our findings suggest that therapy with PLZF-overexpressing T cells would result in overall improved outcomes due to less GVHD and intact GVT effects. PMID:23733752

  16. Transition metals activate TFEB in overexpressing cells

    PubMed Central

    Peña, Karina A.; Kiselyov, Kirill

    2015-01-01

    Transition metal toxicity is an important factor in the pathogenesis of numerous human disorders, including neurodegenerative diseases. Lysosomes have emerged as important factors in transition metal toxicity because they handle transition metals via endocytosis, autophagy, absorption from the cytoplasm and exocytosis. Transcription factor EB (TFEB) regulates lysosomal biogenesis and the expression of lysosomal proteins in response to lysosomal and/or metabolic stresses. Since transition metals cause lysosomal dysfunction, we proposed that TFEB may be activated to drive gene expression in response to transition metal exposure and that such activation may influence transition metal toxicity. We found that transition metals copper (Cu) and iron (Fe) activate recombinant TFEB and stimulate the expression of TFEB-dependent genes in TFEB-overexpressing cells. In cells that show robust lysosomal exocytosis, TFEB was cytoprotective at moderate levels of Cu exposure, decreasing oxidative stress as reported by the expression of heme oxygenase-1 (HMOX1) gene. However, at high levels of Cu exposure, particularly in cells with low levels of lysosomal exocytosis, activation of overexpressed TFEB was toxic, increasing oxidative stress and mitochondrial damage. Based on these data, we conclude that TFEB-driven gene network is a component of the cellular response to transition metals. These data suggest limitations and disadvantages of TFEB overexpression as a therapeutic approach. PMID:26251447

  17. Decidual Cell Polyploidization Necessitates Mitochondrial Activity

    PubMed Central

    Ma, Xinghong; Gao, Fei; Rusie, Allison; Hemingway, Jennifer; Ostmann, Alicia B.; Sroga, Julie M.; Jegga, Anil G.; Das, Sanjoy K.

    2011-01-01

    Cellular polyploidy has been widely reported in nature, yet its developmental mechanism and function remain poorly understood. In the present study, to better define the aspects of decidual cell polyploidy, we isolated pure polyploid and non-polyploid decidual cell populations from the in vivo decidual bed. Three independent RNA pools prepared for each population were then subjected to the Affymetrix gene chip analysis for the whole mouse genome transcripts. Our data revealed up-regulation of 1015 genes and down-regulation of 1207 genes in the polyploid populations, as compared to the non-polyploid group. Comparative RT-PCR and in situ hybridization results indeed confirmed differential expressional regulation of several genes between the two populations. Based on functional enrichment analyses, up-regulated polyploidy genes appeared to implicate several functions, which primarily include cell/nuclear division, ATP binding, metabolic process, and mitochondrial activity, whereas that of down-regulated genes primarily included apoptosis and immune processes. Further analyses of genes that are related to mitochondria and bi-nucleation showed differential and regional expression within the decidual bed, consistent with the pattern of polyploidy. Consistently, studies revealed a marked induction of mitochondrial mass and ATP production in polyploid cells. The inhibition of mitochondrial activity by various pharmacological inhibitors, as well as by gene-specific targeting using siRNA-mediated technology showed a dramatic attenuation of polyploidy and bi-nucleation development during in vitro stromal cell decidualization, suggesting mitochondria play a major role in positive regulation of decidual cell polyploidization. Collectively, analyses of unique polyploidy markers and molecular signaling networks may be useful to further characterize functional aspects of decidual cell polyploidy at the site of implantation. PMID:22046353

  18. Immune cells in term and preterm labor.

    PubMed

    Gomez-Lopez, Nardhy; StLouis, Derek; Lehr, Marcus A; Sanchez-Rodriguez, Elly N; Arenas-Hernandez, Marcia

    2014-11-01

    Labor resembles an inflammatory response that includes secretion of cytokines/chemokines by resident and infiltrating immune cells into reproductive tissues and the maternal/fetal interface. Untimely activation of these inflammatory pathways leads to preterm labor, which can result in preterm birth. Preterm birth is a major determinant of neonatal mortality and morbidity; therefore, the elucidation of the process of labor at a cellular and molecular level is essential for understanding the pathophysiology of preterm labor. Here, we summarize the role of innate and adaptive immune cells in the physiological or pathological activation of labor. We review published literature regarding the role of innate and adaptive immune cells in the cervix, myometrium, fetal membranes, decidua and the fetus in late pregnancy and labor at term and preterm. Accumulating evidence suggests that innate immune cells (neutrophils, macrophages and mast cells) mediate the process of labor by releasing pro-inflammatory factors such as cytokines, chemokines and matrix metalloproteinases. Adaptive immune cells (T-cell subsets and B cells) participate in the maintenance of fetomaternal tolerance during pregnancy, and an alteration in their function or abundance may lead to labor at term or preterm. Also, immune cells that bridge the innate and adaptive immune systems (natural killer T (NKT) cells and dendritic cells (DCs)) seem to participate in the pathophysiology of preterm labor. In conclusion, a balance between innate and adaptive immune cells is required in order to sustain pregnancy; an alteration of this balance will lead to labor at term or preterm. PMID:24954221

  19. Fluorescence activated cell sorting of plant protoplasts.

    PubMed

    Bargmann, Bastiaan O R; Birnbaum, Kenneth D

    2010-01-01

    High-resolution, cell type-specific analysis of gene expression greatly enhances understanding of developmental regulation and responses to environmental stimuli in any multicellular organism. In situ hybridization and reporter gene visualization can to a limited extent be used to this end but for high resolution quantitative RT-PCR or high-throughput transcriptome-wide analysis the isolation of RNA from particular cell types is requisite. Cellular dissociation of tissue expressing a fluorescent protein marker in a specific cell type and subsequent Fluorescence Activated Cell Sorting (FACS) makes it possible to collect sufficient amounts of material for RNA extraction, cDNA synthesis/amplification and microarray analysis. An extensive set of cell type-specific fluorescent reporter lines is available to the plant research community. In this case, two marker lines of the Arabidopsis thaliana root are used: P(SCR;)::GFP (endodermis and quiescent center) and P(WOX5;)::GFP (quiescent center). Large numbers (thousands) of seedlings are grown hydroponically or on agar plates and harvested to obtain enough root material for further analysis. Cellular dissociation of plant material is achieved by enzymatic digestion of the cell wall. This procedure makes use of high osmolarity-induced plasmolysis and commercially available cellulases, pectinases and hemicellulases to release protoplasts into solution. FACS of GFP-positive cells makes use of the visualization of the green versus the red emission spectra of protoplasts excited by a 488 nm laser. GFP-positive protoplasts can be distinguished by their increased ratio of green to red emission. Protoplasts are typically sorted directly into RNA extraction buffer and stored for further processing at a later time. This technique is revealed to be straightforward and practicable. Furthermore, it is shown that it can be used without difficulty to isolate sufficient numbers of cells for transcriptome analysis, even for very scarce

  20. Chronic variable stress activates hematopoietic stem cells

    PubMed Central

    Courties, Gabriel; Dutta, Partha; Iwamoto, Yoshiko; Zaltsman, Alex; von zur Muhlen, Constantin; Bode, Christoph; Fricchione, Gregory L.; Denninger, John; Lin, Charles P.; Vinegoni, Claudio; Libby, Peter; Swirski, Filip K.; Weissleder, Ralph; Nahrendorf, Matthias

    2014-01-01

    Exposure to psychosocial stress is a risk factor for many diseases, including atherosclerosis1,2. While incompletely understood, interaction between the psyche and the immune system provides one potential mechanism linking stress and disease inception and progression. Known crosstalk between the brain and immune system includes the hypothalamic–pituitary–adrenal axis, which centrally drives glucocorticoid production in the adrenal cortex, and the sympathetic–adrenal–medullary axis, which controls stress–induced catecholamine release in support of the fight–or–flight reflex3,4. It remains unknown however if chronic stress changes hematopoietic stem cell activity. Here we show that stress increases proliferation of these most primitive progenitors, giving rise to higher levels of disease–promoting inflammatory leukocytes. We found that chronic stress induced monocytosis and neutrophilia in humans. While investigating the source of leukocytosis in mice, we discovered that stress activates upstream hematopoietic stem cells. Sympathetic nerve fibers release surplus noradrenaline, which uses the β3 adrenergic receptor to signal bone marrow niche cells to decrease CXCL12 levels. Consequently, elevated hematopoietic stem cell proliferation increases output of neutrophils and inflammatory monocytes. When atherosclerosis–prone ApoE−/− mice encounter chronic stress, accelerated hematopoiesis promotes plaque features associated with vulnerable lesions that cause myocardial infarction and stroke in humans. PMID:24952646

  1. STAT3 is a critical cell-intrinsic regulator of human unconventional T cell numbers and function

    PubMed Central

    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

  2. Cernunnos deficiency reduces thymocyte life span and alters the T cell repertoire in mice and humans.

    PubMed

    Vera, Gabriella; Rivera-Munoz, Paola; Abramowski, Vincent; Malivert, Laurent; Lim, Annick; Bole-Feysot, Christine; Martin, Christelle; Florkin, Benoit; Latour, Sylvain; Revy, Patrick; de Villartay, Jean-Pierre

    2013-02-01

    Cernunnos is a DNA repair factor of the nonhomologous end-joining machinery. Its deficiency in humans causes radiosensitive severe combined immune deficiency (SCID) with microcephaly, characterized in part by a profound lymphopenia. In contrast to the human condition, the immune system of Cernunnos knockout (KO) mice is not overwhelmingly affected. In particular, Cernunnos is dispensable during V(D)J recombination in lymphoid cells. Nevertheless, the viability of thymocytes is reduced in Cernunnos KO mice, owing to the chronic activation of a P53-dependent DNA damage response. This translates into a qualitative alteration of the T cell repertoire to one in which the most distal Vα and Jα segments are missing. This results in the contraction of discrete T cell populations, such as invariant natural killer T (iNKT) and mucosa-associated invariant T (MAIT) cells, in both humans and mice. PMID:23207905

  3. Persistent neural activity in head direction cells

    NASA Technical Reports Server (NTRS)

    Taube, Jeffrey S.; Bassett, Joshua P.; Oman, C. M. (Principal Investigator)

    2003-01-01

    Many neurons throughout the rat limbic system discharge in relation to the animal's directional heading with respect to its environment. These so-called head direction (HD) cells exhibit characteristics of persistent neural activity. This article summarizes where HD cells are found, their major properties, and some of the important experiments that have been conducted to elucidate how this signal is generated. The number of HD and angular head velocity cells was estimated for several brain areas involved in the generation of the HD signal, including the postsubiculum, anterior dorsal thalamus, lateral mammillary nuclei and dorsal tegmental nucleus. The HD cell signal has many features in common with what is known about how neural integration is accomplished in the oculomotor system. The nature of the HD cell signal makes it an attractive candidate for using neural network models to elucidate the signal's underlying mechanisms. The conditions that any network model must satisfy in order to accurately represent how the nervous system generates this signal are highlighted and areas where key information is missing are discussed.

  4. Increased Circulating Th17 Cells, Serum IL-17A, and IL-23 in Takayasu Arteritis

    PubMed Central

    Misra, Durga Prasanna; Chaurasia, Smriti

    2016-01-01

    Introduction. Th17, γδT, NK, and NKT cells in peripheral blood and serum IL-17 and IL-23 in Takayasu arteritis (TA) were measured and correlated with disease activity. Methods. Th17 (anti-CD3APC, CD4PECy7, and IL-17PE), NKT, NK (anti-CD3APC, CD56FITC), and γδT (anti-CD3FITC and γδTCRAPC) cells were enumerated by flow cytometry in peripheral blood of 30 patients with TA (ACR1990 criteria) and 20 healthy controls, serum IL-17 and IL-23 measured by ELISA. Relation with disease activity (NIH criteria, ITAS2010) was analyzed (using nonparametric tests, median with interquartile range). Results. Mean age of patients was 33.47 ± 11.78 years (25 females); mean symptom duration was 7.1 ± 5.3 years. 13 were not on immunosuppressants; 12 were active (ITAS2010 ≥ 4). The percentage of Th17 cells was significantly expanded in TA (patients 2.1 (1.5–3.2) versus controls 0.75 (0.32–1.2); p < 0.0001) with no differences in other cell populations. Serum IL-17 and IL-23 (pg/mL) in patients (6.2 (4.6–8.5) and 15 (14.9–26.5), resp.) were significantly higher (p < 0.001) than controls (3.9 (3.9–7.3) and undetectable median value, resp.). Subgroup analysis revealed no correlation of Th17 cells, serum IL-17, and IL-23 with disease activity or medications, nor any significant difference before and after medication. Conclusions. There is significant expansion of Th17 cells and elevated serum IL-17 and IL-23 levels in TA patients compared to healthy controls. PMID:27034824

  5. Increased Circulating Th17 Cells, Serum IL-17A, and IL-23 in Takayasu Arteritis.

    PubMed

    Misra, Durga Prasanna; Chaurasia, Smriti; Misra, Ramnath

    2016-01-01

    Introduction. Th17, γδT, NK, and NKT cells in peripheral blood and serum IL-17 and IL-23 in Takayasu arteritis (TA) were measured and correlated with disease activity. Methods. Th17 (anti-CD3APC, CD4PECy7, and IL-17PE), NKT, NK (anti-CD3APC, CD56FITC), and γδT (anti-CD3FITC and γδTCRAPC) cells were enumerated by flow cytometry in peripheral blood of 30 patients with TA (ACR1990 criteria) and 20 healthy controls, serum IL-17 and IL-23 measured by ELISA. Relation with disease activity (NIH criteria, ITAS2010) was analyzed (using nonparametric tests, median with interquartile range). Results. Mean age of patients was 33.47 ± 11.78 years (25 females); mean symptom duration was 7.1 ± 5.3 years. 13 were not on immunosuppressants; 12 were active (ITAS2010 ≥ 4). The percentage of Th17 cells was significantly expanded in TA (patients 2.1 (1.5-3.2) versus controls 0.75 (0.32-1.2); p < 0.0001) with no differences in other cell populations. Serum IL-17 and IL-23 (pg/mL) in patients (6.2 (4.6-8.5) and 15 (14.9-26.5), resp.) were significantly higher (p < 0.001) than controls (3.9 (3.9-7.3) and undetectable median value, resp.). Subgroup analysis revealed no correlation of Th17 cells, serum IL-17, and IL-23 with disease activity or medications, nor any significant difference before and after medication. Conclusions. There is significant expansion of Th17 cells and elevated serum IL-17 and IL-23 levels in TA patients compared to healthy controls. PMID:27034824

  6. Transgelin-2 in B-Cells Controls T-Cell Activation by Stabilizing T Cell - B Cell Conjugates

    PubMed Central

    Chae, Myoung-Won; Kim, Hye-Ran; Kim, Chang-Hyun; Jun, Chang-Duk; Park, Zee-Yong

    2016-01-01

    The immunological synapse (IS), a dynamic and organized junction between T-cells and antigen presenting cells (APCs), is critical for initiating adaptive immunity. The actin cytoskeleton plays a major role in T-cell reorganization during IS formation, and we previously reported that transgelin-2, an actin-binding protein expressed in T-cells, stabilizes cortical F-actin, promoting T-cell activation in response to antigen stimulation. Transgelin-2 is also highly expressed in B-cells, although no specific function has been reported. In this study, we found that deficiency in transgelin-2 (TAGLN2-/-) in B-cells had little effect on B-cell development and activation, as measured by the expression of CD69, MHC class II molecules, and CD80/86. Nevertheless, in B-cells, transgelin-2 accumulated in the IS during the interaction with T-cells. These results led us to hypothesize that transgelin-2 may also be involved in IS stability in B-cells, thereby influencing T-cell function. Notably, we found that transgelin-2 deficiency in B-cells reduced T-cell activation, as determined by the release of IL-2 and interferon-γ and the expression of CD69. Furthermore, the reduced T-cell activation was correlated with reduced B-cell–T-cell conjugate formation. Collectively, these results suggest that actin stability in B-cells during IS formation is critical for the initiation of adaptive T-cell immunity. PMID:27232882

  7. Cell Micromanipulation with an Active Handheld Micromanipulator

    PubMed Central

    Tabarés, Jaime Cuevas; MacLachlan, Robert A.; Ettensohn, Charles A.

    2012-01-01

    The paper describes the use of an active handheld micromanipulator, known as Micron, for micromanipulation of cells. The device enables users to manipulate objects on the order of tens of microns in size, with the natural ease of use of a fully handheld tool. Micron senses its own position using a purpose-built microscale optical tracker, estimates the erroneous or undesired component of hand motion, and actively corrects it by deflecting its own tool tip using piezoelectric actuators. Benchtop experiments in tip positioning show that active compensation can reduce positioning error by up to 51% compared to unaided performance. Preliminary experiments in bisection of sea urchin embryos exhibit an increased success rate when performed with the help of Micron. PMID:21096452

  8. Notch Signaling Regulates the Homeostasis of Tissue-Restricted Innate-like T Cells.

    PubMed

    Chennupati, Vijaykumar; Koch, Ute; Coutaz, Manuel; Scarpellino, Leonardo; Tacchini-Cottier, Fabienne; Luther, Sanjiv A; Radtke, Freddy; Zehn, Dietmar; MacDonald, H Robson

    2016-08-01

    Although Notch signaling plays important roles in lineage commitment and differentiation of multiple cell types including conventional T cells, nothing is currently known concerning Notch function in innate-like T cells. We have found that the homeostasis of several well-characterized populations of innate-like T cells including invariant NKT cells (iNKT), CD8ααTCRαβ small intestinal intraepithelial lymphocytes, and innate memory phenotype CD8 T cells is controlled by Notch. Notch selectively regulates hepatic iNKT cell survival via tissue-restricted control of B cell lymphoma 2 and IL-7Rα expression. More generally, Notch regulation of innate-like T cell homeostasis involves both cell-intrinsic and -extrinsic mechanisms and relies upon context-dependent interactions with Notch ligand-expressing fibroblastic stromal cells. Collectively, using conditional ablation of Notch receptors on peripheral T cells or Notch ligands on putative fibroblastic stromal cells, we show that Notch signaling is indispensable for the homeostasis of three tissue-restricted populations of innate-like T cells: hepatic iNKT, CD8ααTCRαβ small intestinal intraepithelial lymphocytes, and innate memory phenotype CD8 T cells, thus supporting a generalized role for Notch in innate T cell homeostasis. PMID:27324132

  9. Active stochastic stress fluctuations in the cell cytoskeleton stir the cell and activate primary cilia

    NASA Astrophysics Data System (ADS)

    Schmidt, Christoph F.; Fakhri, Nikta; Battle, Christopher; Ott, Carolyn M.; Wessel, Alok D.; Lippincott-Schwartz, Jennifer; Mackintosh, Frederick C.

    2015-03-01

    Cells are active systems with molecular force generation that drives complex dynamics at the supramolecular scale. Much of cellular dynamics is driven by myosin motors interacting with the actin cytoskeleton. We discovered active random ``stirring'' driven by cytoplasmic myosin as an intermediate mode of transport, different from both thermal diffusion and directed motor activity. We found a further manifestation of cytoskeletal dynamics in the active motion patterns of primary cilia generated by epithelial cells. These cilia were thought to be immotile due to the absence of dynein motors, but it turns out that their anchoring deeper inside the cell in combination with the strongly fluctuating cortex results in clearly measurable non-equilibrium fluctuations.

  10. Endogenous ligands of natural killer T cells are alpha-linked glycosylceramides.

    PubMed

    Kain, Lisa; Costanzo, Anne; Webb, Bill; Holt, Marie; Bendelac, Albert; Savage, Paul B; Teyton, Luc

    2015-12-01

    The nature of the endogenous ligands for natural killer T (NKT) cells has been debated for more than a decade. Because the mammalian glycosylceramide synthases are invertases, it is believed that in mammals all glycosylceramides are β anomers. However, the possibility that an alternative enzymatic pathway, an unfaithful enzyme, or unique physico-chemical environments could allow the production of small quantities of α anomers should be entertained. Classic biochemical and chemical analysis approaches are not well suited for this challenge as they lack sensitivity. Using a combination of biological assays and new technological approaches, we have unequivocally demonstrated that α glycosylceramides were constitutively produced by mammalian immune cells, loaded onto CD1d and presented to NKT cells both in the thymus and in the periphery. Their amount is controlled tightly by catabolic enzymes, and can be altered in vitro and in vivo to modify NKT cell behavior. PMID:26141240

  11. Probing cell activity in random access modality

    NASA Astrophysics Data System (ADS)

    Sacconi, L.; Crocini, C.; Lotti, J.; Coppini, R.; Ferrantini, C.; Tesi, C.; Yan, P.; Loew, L. M.; Cerbai, E.; Poggesi, C.; Pavone, F. S.

    2013-06-01

    We combined the advantage of an ultrafast random access microscope with novel labelling technologies to study the intra- and inter-cellular action potential propagation in neurons and cardiac myocytes with sub-millisecond time resolution. The random accesses microscopy was used in combination with a new fluorinated voltage sensitive dye with improved photostability to record membrane potential from multiple Purkinje cells with near simultaneous sampling. The RAMP system rapidly scanned between lines drawn in the membranes of neurons to perform multiplex measurements of the TPF signal. This recording was achieved by rapidly positioning the laser excitation with the AOD to sample a patch of membrane from each cell in <100 μs for recording from five cells, multiplexing permits a temporal resolution of 400 μs sufficient to capture every spike. The system is capable to record spontaneous activity over 800 ms from five neighbouring cells simultaneously, showing that spiking is not temporally correlated. The system was also used to investigate the electrical properties of tubular system (TATS) in isolated rat ventricular myocytes.

  12. Hymenoptera Allergy and Mast Cell Activation Syndromes.

    PubMed

    Bonadonna, Patrizia; Bonifacio, Massimiliano; Lombardo, Carla; Zanotti, Roberta

    2016-01-01

    Mast cell activation syndrome (MCAS) can be diagnosed in patients with recurrent, severe symptoms from mast cell (MC)-derived mediators, which are transiently increased in serum and are attenuated by mediator-targeting drugs. When KIT-mutated, clonal MC are detected in these patients, a diagnosis of primary MCAS can be made. Severe systemic reactions to hymenoptera venom (HV) represent the most common form of anaphylaxis in patients with mastocytosis. Patients with primary MCAS and HV anaphylaxis are predominantly males and do not have skin lesions in the majority of cases, and anaphylaxis is characterized by hypotension and syncope in the absence of urticaria and angioedema. A normal value of tryptase (≤11.4 ng/ml) in these patients does not exclude a diagnosis of mastocytosis. Patients with primary MCAS and HV anaphylaxis have to undergo lifelong venom immunotherapy, in order to prevent further potentially fatal severe reactions. PMID:26714690

  13. Sertoli Cells Maintain Leydig Cell Number and Peritubular Myoid Cell Activity in the Adult Mouse Testis

    PubMed Central

    Monteiro, Ana; Milne, Laura; Cruickshanks, Lyndsey; Jeffrey, Nathan; Guillou, Florian; Freeman, Tom C.; Mitchell, Rod T.; Smith, Lee B.

    2014-01-01

    The Sertoli cells are critical regulators of testis differentiation and development. In the adult, however, their known function is restricted largely to maintenance of spermatogenesis. To determine whether the Sertoli cells regulate other aspects of adult testis biology we have used a novel transgenic mouse model in which Amh-Cre induces expression of the receptor for Diphtheria toxin (iDTR) specifically within Sertoli cells. This causes controlled, cell-specific and acute ablation of the Sertoli cell population in the adult animal following Diphtheria toxin injection. Results show that Sertoli cell ablation leads to rapid loss of all germ cell populations. In addition, adult Leydig cell numbers decline by 75% with the remaining cells concentrated around the rete and in the sub-capsular region. In the absence of Sertoli cells, peritubular myoid cell activity is reduced but the cells retain an ability to exclude immune cells from the seminiferous tubules. These data demonstrate that, in addition to support of spermatogenesis, Sertoli cells are required in the adult testis both for retention of the normal adult Leydig cell population and for support of normal peritubular myoid cell function. This has implications for our understanding of male reproductive disorders and wider androgen-related conditions affecting male health. PMID:25144714

  14. Mitochondrial uncouplers inhibit hepatic stellate cell activation

    PubMed Central

    2012-01-01

    Background Mitochondrial dysfunction participates in the progression of several pathologies. Although there is increasing evidence for a mitochondrial role in liver disease, little is known about its contribution to hepatic stellate cell (HSC) activation. In this study we investigated the role of mitochondrial activity through mild uncoupling during in vitro activation of HSCs. Methods Cultured primary human and mouse HSCs were treated with the chemical uncouplers FCCP and Valinomycin. ATP levels were measured by luciferase assay and production of reactive oxygen species was determined using the fluorescent probe DCFH-DA. Possible cytotoxicity by uncoupler treatment was evaluated by caspase 3/7 activity and cytoplasmic protease leakage. Activation of HSCs and their response to the pro-fibrogenic cytokine TGF-β was evaluated by gene expression of activation markers and signal mediators using RT-qPCR. Proliferation was measured by incorporation of EdU and protein expression of α-smooth muscle actin was analyzed by immunocytochemistry and western blot. Results FCCP and Valinomycin treatment mildly decreased ATP and reactive oxygen species levels. Both uncouplers increased the expression of mitochondrial genes such as Tfam and COXIV while inducing morphological features of quiescent mouse HSCs and abrogating TGF-β signal transduction. Mild uncoupling reduced HSC proliferation and expression of pro-fibrogenic markers of mouse and human HSCs. Conclusions Mild mitochondrial uncoupling inhibits culture-induced HSC activation and their response to pro-fibrogenic cytokines like TGF-β. These results therefore suggest mitochondrial uncoupling of HSCs as a strategy to reduce progression of liver fibrosis. PMID:22686625

  15. Activity of nintedanib in germ cell tumors.

    PubMed

    Steinemann, Gustav; Jacobsen, Christine; Gerwing, Mirjam; Hauschild, Jessica; von Amsberg, Gunhild; Höpfner, Michael; Nitzsche, Bianca; Honecker, Friedemann

    2016-02-01

    Germ cell tumors (GCTs) are the most frequent malignancy in male patients between 15 and 45 years of age. Cisplatin-based chemotherapy shows excellent cure rates, but patients with cisplatin-resistant GCTs have a poor prognosis. Nintedanib (BIBF 1120, Vargatef) inhibits the receptor classes vascular endothelial growth factor receptor, platelet derived growth factor receptor, and fibroblast growth factor receptor, and has shown activity against many tumors, as well as in idiopathic lung fibrosis and bleomycin-induced lung injury. Here, we investigated the antineoplastic and antiangiogenic properties of nintedanib in cisplatin-resistant and cisplatin-sensitive GCT cells, both alone and in combination with classical cytotoxic agents such as cisplatin, etoposide, and bleomycin. The half-maximal inhibitory concentration (IC50) of nintedanib was 4.5 ± 0.43 μmol/l, 3.1 ± 0.45 μmol/l, and 3.6 ± 0.33 μmol/l in cisplatin-sensitive NTERA2, 2102Ep, and NCCIT cells, whereas the IC50 doses of the cisplatin-resistant counterparts were 6.6 ± 0.37 μmol/l (NTERA2-R), 4.5 ± 0.83 μmol/l (2102Ep-R), and 6.1 ± 0.41 μmol/l (NCCIT-R), respectively. Single treatment with nintedanib induced apoptosis and resulted in a sustained reduction in the capacity of colony formation in both cisplatin-sensitive and cisplatin-resistant GCT cells. Cell cycle analysis showed that nintedanib induced a strong G0/G1-phase arrest in all investigated cell lines. Combination treatment with cisplatin did not result in additive, synergistic, or antagonistic effects. The in-vivo activity was studied using the chorioallantoic membrane assay and indicated the antiangiogenic potency of nintedanib with markedly reduced microvessel density. Topical treatment of inoculated tumor plaques resulted in a significant reduction of the tumor size. This indicates that nintedanib might be a promising substance in the treatment of GCT. PMID:26479145

  16. T helper cell activation and human retroviral pathogenesis.

    PubMed Central

    Copeland, K F; Heeney, J L

    1996-01-01

    T helper (Th) cells are of central importance in regulating many critical immune effector mechanisms. The profile of cytokines produced by Th cells correlates with the type of effector cells induced during the immune response to foreign antigen. Th1 cells induce the cell-mediated immune response, while Th2 cells drive antibody production. Th cells are the preferential targets of human retroviruses. Infections with human T-cell leukemia virus (HTLV) or human immunodeficiency virus (HIV) result in the expansion of Th cells by the action of HTLV (adult T-cell leukemia) or the progressive loss of T cells by the action of HIV (AIDS). Both retrovirus infections impart a high-level activation state in the host immune cells as well as systemically. However, diverging responses to this activation state have contrasting effects on the Th-cell population. In HIV infection, Th-cell loss has been attributed to several mechanisms, including a selective elimination of cells by apoptosis. The induction of apoptosis in HIV infection is complex, with many different pathways able to induce cell death. In contrast, infection of Th cells with HTLV-1 affords the cell a protective advantage against apoptosis. This advantage may allow the cell to escape immune surveillance, providing the opportunity for the development of Th-cell cancer. In this review, we will discuss the impact of Th-cell activation and general immune activation on human retrovirus expression with a focus upon Th-cell function and the progression to disease. PMID:8987361

  17. Effect of Broccoli Sprouts and Live Attenuated Influenza Virus on Peripheral Blood Natural Killer Cells: A Randomized, Double-Blind Study

    PubMed Central

    Müller, Loretta; Meyer, Megan; Bauer, Rebecca N.; Zhou, Haibo; Zhang, Hongtao; Jones, Shannon; Robinette, Carole; Noah, Terry L.; Jaspers, Ilona

    2016-01-01

    Enhancing antiviral host defense responses through nutritional supplementation would be an attractive strategy in the fight against influenza. Using inoculation with live attenuated influenza virus (LAIV) as an infection model, we have recently shown that ingestion of sulforaphane-containing broccoli sprout homogenates (BSH) reduces markers of viral load in the nose. To investigate the systemic effects of short-term BSH supplementation in the context of LAIV-inoculation, we examined peripheral blood immune cell populations in non-smoking subjects from this study, with a particular focus on NK cells. We carried out a randomized, double-blinded, placebo-controlled study measuring the effects of BSH (N = 13) or placebo (alfalfa sprout homogenate, ASH; N = 16) on peripheral blood mononuclear cell responses to a standard nasal vaccine dose of LAIV in healthy volunteers. Blood was drawn prior to (day-1) and post (day2, day21) LAIV inoculation and analyzed for neutrophils, monocytes, macrophages, T cells, NKT cells, and NK cells. In addition, NK cells were enriched, stimulated, and assessed for surface markers, intracellular markers, and cytotoxic potential by flow cytometry. Overall, LAIV significantly reduced NKT (day2 and day21) and T cell (day2) populations. LAIV decreased NK cell CD56 and CD158b expression, while significantly increasing CD16 expression and cytotoxic potential (on day2). BSH supplementation further increased LAIV-induced granzyme B production (day2) in NK cells compared to ASH and in the BSH group granzyme B levels appeared to be negatively associated with influenza RNA levels in nasal lavage fluid cells. We conclude that nasal influenza infection may induce complex changes in peripheral blood NK cell activation, and that BSH increases virus-induced peripheral blood NK cell granzyme B production, an effect that may be important for enhanced antiviral defense responses. Trial Registration: ClinicalTrials.gov NCT01269723 PMID:26820305

  18. Kinase Activity Studied in Living Cells Using an Immunoassay

    ERIC Educational Resources Information Center

    Bavec, Aljos?a

    2014-01-01

    This laboratory exercise demonstrates the use of an immunoassay for studying kinase enzyme activity in living cells. The advantage over the classical method, in which students have to isolate the enzyme from cell material and measure its activity in vitro, is that enzyme activity is modulated and measured in living cells, providing a more…

  19. Random mitotic activities across human embryonic stem cell colonies.

    SciTech Connect

    Jin, Q.; Duggan, R.; Dasa, S.; Li, F.; Chen, L.

    2010-08-01

    A systemic and quantitative study was performed to examine whether different levels of mitotic activities, assessed by the percentage of S-phase cells at any given time point, existed at different physical regions of human embryonic stem (hES) cell colonies at 2, 4, 6 days after cell passaging. Mitotically active cells were identified by the positive incorporation of 5-bromo-2-deoxyuridine (BrdU) within their newly synthesized DNA. Our data indicated that mitotically active cells were often distributed as clusters randomly across the colonies within the examined growth period, presumably resulting from local deposition of newly divided cells. This latter notion was further demonstrated by the confined growth of enhanced green florescence protein (EGFP) expressing cells amongst non-GFP expressing cells. Furthermore, the overall percentage of mitotically active cells remained constantly at about 50% throughout the 6-day culture period, indicating mitotic activities of hES cell cultures were time-independent under current growth conditions.

  20. Mast cell activation syndrome masquerading as agranulocytosis.

    PubMed

    Afrin, Lawrence B

    2012-01-01

    Acquired agranulocytosis is a rare, life-threatening disorder. The few known causes/associations usually are readily identifiable (e.g., drug reaction, Felty syndrome, megaloblastosis, large granular lymphocytic leukemia, etc.). We report a novel association with mast cell disease. A 61-year-old morbidly obese man developed rheumatoid arthritis unresponsive to several medications. Agranulocytosis developed shortly after sulfasalazine was started but did not improve when the drug was soon stopped. Other symptoms across many systems developed including hives and presyncope. Marrow aspiration and biopsy showed only neutropenia. Serum tryptase was mildly elevated; urinary prostaglandin D2 was markedly elevated. Other causes were not found. Mast cell activation syndrome (MCAS) was diagnosed. Oral antihistamines, montelukast, and cromolyn were unhelpful; aspirin was initially felt contraindicated. Imatinib immediately increased neutrophils from 0% to 25% but did not help symptoms; subsequent addition of aspirin increased neutrophils further and abated symptoms. Different presentations of different MCAS patients reflect elaboration of different mediators likely consequent to different Kit mutations. Mast cells (MCs) help regulate adipocytes, and adipocytes can inhibit granulopoiesis; thus, a Kit-mutated MC clone may have directly and/or indirectly driven agranulocytosis. MCAS should be considered in otherwise idiopathic agranulocytosis presenting with comorbidities best explained by MC mediator release. PMID:22338992

  1. Zbtb16 (PLZF) is stably suppressed and not inducible in non-innate T cells via T cell receptor-mediated signaling

    PubMed Central

    Zhang, Sai; Laouar, Amale; Denzin, Lisa K.; Sant’Angelo, Derek B.

    2015-01-01

    The transcription factor PLZF (promyelocytic leukemia zinc finger; zbtb16) is essential for nearly all of the unique characteristics of NKT cells including their rapid and potent response to antigen. In the immune system, zbtb16 expression is only found in innate cells. Conventional T cells that ectopically express PLZF spontaneously acquire an activated, effector phenotype. Activation induced expression of lineage defining transcription factors such as T-bet, FoxP3, RORγt, GATA3 and others is essential for naïve T cell differentiation into effector T cells. In this study, we used sensitive genetic-based approaches to assess the induction of PLZF expression in non-innate T cells by T cell receptor (TCR)-mediated activation. Surprisingly, we found that PLZF was stably repressed in non-innate T cells and that TCR-mediated signaling was not sufficient to induce PLZF in conventional T cells. The inactivated state of PLZF was stably maintained in mature T cells, even under inflammatory conditions imposed by bacterial infection. Collectively, our data show that, in contrast to multiple recent reports, PLZF expression is highly specific to innate T cells and cannot be induced in conventional T cells via TCR-mediated activation or inflammatory challenge. PMID:26178856

  2. MAIT cells are activated during human viral infections.

    PubMed

    van Wilgenburg, Bonnie; Scherwitzl, Iris; Hutchinson, Edward C; Leng, Tianqi; Kurioka, Ayako; Kulicke, Corinna; de Lara, Catherine; Cole, Suzanne; Vasanawathana, Sirijitt; Limpitikul, Wannee; Malasit, Prida; Young, Duncan; Denney, Laura; Moore, Michael D; Fabris, Paolo; Giordani, Maria Teresa; Oo, Ye Htun; Laidlaw, Stephen M; Dustin, Lynn B; Ho, Ling-Pei; Thompson, Fiona M; Ramamurthy, Narayan; Mongkolsapaya, Juthathip; Willberg, Christian B; Screaton, Gavin R; Klenerman, Paul

    2016-01-01

    Mucosal-associated invariant T (MAIT) cells are abundant in humans and recognize bacterial ligands. Here, we demonstrate that MAIT cells are also activated during human viral infections in vivo. MAIT cells activation was observed during infection with dengue virus, hepatitis C virus and influenza virus. This activation-driving cytokine release and Granzyme B upregulation-is TCR-independent but dependent on IL-18 in synergy with IL-12, IL-15 and/or interferon-α/β. IL-18 levels and MAIT cell activation correlate with disease severity in acute dengue infection. Furthermore, HCV treatment with interferon-α leads to specific MAIT cell activation in vivo in parallel with an enhanced therapeutic response. Moreover, TCR-independent activation of MAIT cells leads to a reduction of HCV replication in vitro mediated by IFN-γ. Together these data demonstrate MAIT cells are activated following viral infections, and suggest a potential role in both host defence and immunopathology. PMID:27337592

  3. Chronic lymphocytic leukemia: a disease of activated monoclonal B cells

    PubMed Central

    Damle, Rajendra N.; Calissano, Carlo; Chiorazzi, Nicholas

    2010-01-01

    B-cell type chronic lymphocytic leukemia (CLL) has long been considered a disease of resting lymphocytes. However cell surface and intracellular phenotypes suggest that most CLL cells are activated cells, although only a small subset progresses beyond the G1 stage of the cell cycle. In addition, traditional teaching says that CLL cells divide rarely, and therefore the buildup of leukemic cells is due to an inherent defect in cell death. However, in vivo labeling of CLL cells indicates a much more active rate of cell birth than originally estimated, suggesting that CLL is a dynamic disease. Here we review the observations that have led to these altered views of the activation state and proliferative capacities of CLL cells and also provide our interpretation of these observations in light of their potential impact on patients. PMID:20620969

  4. Helicobacter pylori Cholesteryl α-Glucosides Contribute to Its Pathogenicity and Immune Response by Natural Killer T Cells

    PubMed Central

    Ito, Yuki; Vela, Jose Luis; Matsumura, Fumiko; Hoshino, Hitomi; Tyznik, Aaron; Lee, Heeseob; Girardi, Enrico; Zajonc, Dirk M.; Liddington, Robert; Kobayashi, Motohiro; Bao, Xingfeng; Bugaytsova, Jeanna; Borén, Thomas; Jin, Rongsheng; Zong, Yinong; Seeberger, Peter H.; Nakayama, Jun; Kronenberg, Mitchell; Fukuda, Minoru

    2013-01-01

    Approximately 10–15% of individuals infected with Helicobacter pylori will develop ulcer disease (gastric or duodenal ulcer), while most people infected with H. pylori will be asymptomatic. The majority of infected individuals remain asymptomatic partly due to the inhibition of synthesis of cholesteryl α-glucosides in H. pylori cell wall by α1,4-GlcNAc-capped mucin O-glycans, which are expressed in the deeper portion of gastric mucosa. However, it has not been determined how cholesteryl α-glucosyltransferase (αCgT), which forms cholesteryl α-glucosides, functions in the pathogenesis of H. pylori infection. Here, we show that the activity of αCgT from H. pylori clinical isolates is highly correlated with the degree of gastric atrophy. We investigated the role of cholesteryl α-glucosides in various aspects of the immune response. Phagocytosis and activation of dendritic cells were observed at similar degrees in the presence of wild-type H. pylori or variants harboring mutant forms of αCgT showing a range of enzymatic activity. However, cholesteryl α-glucosides were recognized by invariant natural killer T (iNKT) cells, eliciting an immune response in vitro and in vivo. Following inoculation of H. pylori harboring highly active αCgT into iNKT cell-deficient (Jα18−/−) or wild-type mice, bacterial recovery significantly increased in Jα18−/− compared to wild-type mice. Moreover, cytokine production characteristic of Th1 and Th2 cells dramatically decreased in Jα18−/− compared to wild-type mice. These findings demonstrate that cholesteryl α-glucosides play critical roles in H. pylori-mediated gastric inflammation and precancerous atrophic gastritis. PMID:24312443

  5. The panoply of αβT cells in the skin.

    PubMed

    Nomura, Takashi; Kabashima, Kenji; Miyachi, Yoshiki

    2014-10-01

    Skin protects body from continual attack by microbial pathogens and environmental factors. Such barrier function of skin is achieved by multiple components including immune system, which is mainly regulated by lymphocytes. T lymphocytes (T cells) that express T cell receptor (TCR) α and β chains (αβT cells) control the strength and the type of immune response. CD4T cell population consists of helper T (Th) cell-subsets and immunosuppressive regulatory T (Treg) cells. Th1 cells produce IFN-γ and protect against intracellular pathogens. Th2 cells produce IL-4 family cytokines and participate in allergic skin diseases, including atopic dermatitis (AD). Th17 cells secrete IL-17, recruit granulocytes to fight against extracellular microorganisms, and play a role in psoriasis and AD. Th22 cells produce IL-22 that activates epithelial cells and mediates acanthosis in psoriasis and AD. On the other hand, Foxp3+ Treg cells attenuate immune responses partly via TGF-β or IL-10. Tissue resident memory T (Trm) cells in the skin-most of which are epidermal CD8T cells-constitute the first line of the defense against repeated infections. CD8 T cells are also engaged in psoriasis, lichen planus, and drug eruptions. Skin harbors innate-like αβT cells such as natural killer T (NKT) cells as well, whose function is not fully revealed. Understanding these αβT cells helps to comprehend skin diseases. PMID:25190363

  6. Hyperoxia Inhibits T Cell Activation in Mice

    NASA Astrophysics Data System (ADS)

    Hughes-Fulford, M.; Meissler, J.; Aguayo, E. T.; Globus, R.; Aguado, J.; Candelario, T.

    2013-02-01

    , spleens were removed and the splenocytes were isolated and kept as individual biological samples. We have also examined transcription factors (JASPAR) and pathways of the immune system to help us understand the mechanism of regulation. Results: Our recent mouse immunology experiment aboard STS-131 suggests that the early T cell immune response was inhibited in animals that have been exposed to spaceflight, even 24 hours after return to earth. Moreover, recent experiments in hyperoxic mice show that many of the same genes involved in early T cell activation were altered. Specifically, expression of IL-2Rα, Cxcl2, TNFα, FGF2, LTA and BCL2 genes are dysregulated in mice exposed to hyperoxia. Conclusions: If these hyperoxia-induced changes of gene expression in early T cell activation are additive to the changes seen in the microgravity of spaceflight, there could be an increased infection risk to EVA astronauts, which should be addressed prior to conducting a Mars or other long-term mission.

  7. In vivo administration of the frog skin peptide frenatin 2.1S induces immunostimulatory phenotypes of mouse mononuclear cells.

    PubMed

    Pantic, Jelena M; Radosavljevic, Gordana D; Jovanovic, Ivan P; Arsenijevic, Nebojsa N; Conlon, J Michael; Lukic, Miodrag L

    2015-09-01

    Host-defense peptides secreted by epithelial cells exhibit cytotoxic and immunoregulatory effects in order to protect the organism against invading microorganisms. Antimicrobial peptides derived from frog skin display both immunostimulatory and immunosuppressive actions as demonstrated by in vitro cytokine production by macrophages. Frenatin 2.1S, first isolated from skin secretions of the frog, Sphaenorhynchus lacteus (Hylidae), enhances the in vitro production of pro-inflammatory IL-1β, TNF-α and IL-23 by mouse peritoneal cells. In order to test whether the immunostimulatory action of frenatin 2.1S may be reproduced in vivo, effects of intraperitoneal injections of this peptide on mononuclear cells in the peritoneum and spleen were determined 24h after administration. The data indicate that frenatin 2.1S enhances the activation state and homing capacity of Th1 type lymphocytes and NKT cells in the mouse peritoneal cavity, as evaluated by increased expression of early activation marker CD69 among T and NKT cells and chemokine receptor CXCR3 among T cells. Frenatin 2.1S significantly increases the percentage of (F4/80(+)CD11c(+)CD206(+)) pro-inflammatory M1 macrophages and enhances the expression of MHC class II molecules on F4/80(+)CD11c(+) macrophages in the mouse peritoneal cavity. Additionally, injection of frenatin 2.1S, in the presence or absence of lipopolysaccharide, increases the percentage of peritoneal B cells of the (CD19(+)CD11b(+)CD5(+)) B1a phenotype thus contributing to an inflammatory milieu. We suggest that the immunostimulatory effect of frenatin 2.1S may have therapeutic relevance in disease states, such as certain types of cancer, in which an enhanced inflammatory response may be beneficial. PMID:25861850

  8. Elasticity of adherent active cells on a compliant substrate

    NASA Astrophysics Data System (ADS)

    Banerjee, Shiladitya; Mertz, Aaron F.; Dufresne, Eric R.; Marchetti, M. Cristina

    2012-02-01

    We present a continuum mechanical model of rigidity sensing by livings cells adhering to a compliant substrate. The cell or cell colony is modeled as an elastic active gel, adapting recently developed continuum theories of active viscoelastic fluids. The coupling to the substrate enters as a boundary condition that relates the cell's deformation field to local stress gradients. In the presence of activity, the substrate induces spatially inhomogeneous contractile stresses and deformations, with a power law dependence of the total traction forces on cell or colony size. This is in agreement with recent experiments on keratinocyte colonies adhered to fibronectin coated surfaces. In the presence of acto-myosin activity, the substrate also enhances the cell polarization, breaking the cell's front-rear symmetry. Maximal polarization is observed when the substrate stiffness matches that of the cell, in agreement with experiments on stem cells.

  9. MAIT cells are activated during human viral infections

    PubMed Central

    van Wilgenburg, Bonnie; Scherwitzl, Iris; Hutchinson, Edward C.; Leng, Tianqi; Kurioka, Ayako; Kulicke, Corinna; de Lara, Catherine; Cole, Suzanne; Vasanawathana, Sirijitt; Limpitikul, Wannee; Malasit, Prida; Young, Duncan; Denney, Laura; Barnes, Eleanor; Ball, Jonathan; Burgess, Gary; Cooke, Graham; Dillon, John; Gore, Charles; Foster, Graham; Guha, Neil; Halford, Rachel; Herath, Cham; Holmes, Chris; Howe, Anita; Hudson, Emma; Irving, William; Khakoo, Salim; Koletzki, Diana; Martin, Natasha; Mbisa, Tamyo; McKeating, Jane; McLauchlan, John; Miners, Alec; Murray, Andrea; Shaw, Peter; Simmonds, Peter; Spencer, Chris; Targett-Adams, Paul; Thomson, Emma; Vickerman, Peter; Zitzmann, Nicole; Moore, Michael D.; Fabris, Paolo; Giordani, Maria Teresa; Oo, Ye Htun; Laidlaw, Stephen M.; Dustin, Lynn B.; Ho, Ling-Pei; Thompson, Fiona M.; Ramamurthy, Narayan; Mongkolsapaya, Juthathip; Willberg, Christian B.; Screaton, Gavin R.; Klenerman, Paul

    2016-01-01

    Mucosal-associated invariant T (MAIT) cells are abundant in humans and recognize bacterial ligands. Here, we demonstrate that MAIT cells are also activated during human viral infections in vivo. MAIT cells activation was observed during infection with dengue virus, hepatitis C virus and influenza virus. This activation—driving cytokine release and Granzyme B upregulation—is TCR-independent but dependent on IL-18 in synergy with IL-12, IL-15 and/or interferon-α/β. IL-18 levels and MAIT cell activation correlate with disease severity in acute dengue infection. Furthermore, HCV treatment with interferon-α leads to specific MAIT cell activation in vivo in parallel with an enhanced therapeutic response. Moreover, TCR-independent activation of MAIT cells leads to a reduction of HCV replication in vitro mediated by IFN-γ. Together these data demonstrate MAIT cells are activated following viral infections, and suggest a potential role in both host defence and immunopathology. PMID:27337592

  10. Functionally Active Gap Junctions between Connexin 43-Positive Mesenchymal Stem Cells and Glioma Cells.

    PubMed

    Gabashvili, A N; Baklaushev, V P; Grinenko, N F; Levinskii, A B; Mel'nikov, P A; Cherepanov, S A; Chekhonin, V P

    2015-05-01

    The formation of functional gap junctions between mesenchymal stem cells and cells of low-grade rat glioma C6 cells was studied in in vitro experiments. Immunocytochemical analysis with antibodies to connexin 43 extracellular loop 2 showed that mesenchymal stem cells as well as C6 glioma cells express the main astroglial gap junction protein connexin 43. Analysis of migration activity showed that mesenchymal stem cells actively migrate towards C6 glioma cells. During co-culturing, mesenchymal stem cells and glioma C6 form functionally active gap junctions mediating the transport of cytoplasmic dye from glioma cells to mesenchymal stem cells in the opposite direction. Fluorometry showed that the intensity of transport of low-molecular substances through heterologous gap junctions between mesenchymal stem cells and glioma cells is similar to that through homologous gap junctions between glioma cells. This phenomenon can be used for the development of new methods of cell therapy of high-grade gliomas. PMID:26033611

  11. Single cell multiplexed assay for proteolytic activity using droplet microfluidics.

    PubMed

    Ng, Ee Xien; Miller, Miles A; Jing, Tengyang; Chen, Chia-Hung

    2016-07-15

    Cellular enzymes interact in a post-translationally regulated fashion to govern individual cell behaviors, yet current platform technologies are limited in their ability to measure multiple enzyme activities simultaneously in single cells. Here, we developed multi-color Förster resonance energy transfer (FRET)-based enzymatic substrates and use them in a microfluidics platform to simultaneously measure multiple specific protease activities from water-in-oil droplets that contain single cells. By integrating the microfluidic platform with a computational analytical method, Proteolytic Activity Matrix Analysis (PrAMA), we are able to infer six different protease activity signals from individual cells in a high throughput manner (~100 cells/experimental run). We characterized protease activity profiles at single cell resolution for several cancer cell lines including breast cancer cell line MDA-MB-231, lung cancer cell line PC-9, and leukemia cell line K-562 using both live-cell and in-situ cell lysis assay formats, with special focus on metalloproteinases important in metastasis. The ability to measure multiple proteases secreted from or expressed in individual cells allows us to characterize cell heterogeneity and has potential applications including systems biology, pharmacology, cancer diagnosis and stem cell biology. PMID:26995287

  12. The Epstein-Barr Virus Glycoprotein gp150 Forms an Immune-Evasive Glycan Shield at the Surface of Infected Cells

    PubMed Central

    Gram, Anna M.; Oosenbrug, Timo; Lindenbergh, Marthe F. S.; Büll, Christian; Comvalius, Anouskha; Dickson, Kathryn J. I.; Wiegant, Joop; Vrolijk, Hans; Lebbink, Robert Jan; Wolterbeek, Ron; Adema, Gosse J.; Griffioen, Marieke; Heemskerk, Mirjam H. M.; Tscharke, David C.; Hutt-Fletcher, Lindsey M.; Ressing, Maaike E.

    2016-01-01

    Cell-mediated immunity plays a key role in host control of viral infection. This is exemplified by life-threatening reactivations of e.g. herpesviruses in individuals with impaired T-cell and/or iNKT cell responses. To allow lifelong persistence and virus production in the face of primed immunity, herpesviruses exploit immune evasion strategies. These include a reduction in viral antigen expression during latency and a number of escape mechanisms that target antigen presentation pathways. Given the plethora of foreign antigens expressed in virus-producing cells, herpesviruses are conceivably most vulnerable to elimination by cell-mediated immunity during the replicative phase of infection. Here, we show that a prototypic herpesvirus, Epstein-Barr virus (EBV), encodes a novel, broadly acting immunoevasin, gp150, that is expressed during the late phase of viral replication. In particular, EBV gp150 inhibits antigen presentation by HLA class I, HLA class II, and the non-classical, lipid-presenting CD1d molecules. The mechanism of gp150-mediated T-cell escape does not depend on degradation of the antigen-presenting molecules nor does it require gp150’s cytoplasmic tail. Through its abundant glycosylation, gp150 creates a shield that impedes surface presentation of antigen. This is an unprecedented immune evasion mechanism for herpesviruses. In view of its likely broader target range, gp150 could additionally have an impact beyond escape of T cell activation. Importantly, B cells infected with a gp150-null mutant EBV displayed rescued levels of surface antigen presentation by HLA class I, HLA class II, and CD1d, supporting an important role for iNKT cells next to classical T cells in fighting EBV infection. At the same time, our results indicate that EBV gp150 prolongs the timespan for producing viral offspring at the most vulnerable stage of the viral life cycle. PMID:27077376

  13. Activated Muscle Satellite Cells Chase Ghosts.

    PubMed

    Mourikis, Philippos; Relaix, Frédéric

    2016-02-01

    The in vivo behaviors of skeletal muscle stem cells, i.e., satellite cells, during homeostasis and after injury are poorly understood. In this issue of Cell Stem Cell, Webster et al. (2016) now perform a tour de force intravital microscopic analysis of this population, showing that "ghost fiber" remnants act as scaffolds to guide satellite cell divisions after injury. PMID:26849298

  14. Role of Innate T Cells in Anti-Bacterial Immunity

    PubMed Central

    Gao, Yifang; Williams, Anthony P.

    2015-01-01

    Innate T cells are a heterogeneous group of αβ and γδ T cells that respond rapidly (<2 h) upon activation. These innate T cells also share a non MHC class I or II restriction requirement for antigen recognition. Three major populations within the innate T cell group are recognized, namely, invariant NKT cells, mucosal associated invariant T cells, and gamma delta T cells. These cells recognize foreign/self-lipid presented by non-classical MHC molecules, such as CD1d, MR1, and CD1a. They are activated during the early stages of bacterial infection and act as a bridge between the innate and adaptive immune systems. In this review, we focus on the functional properties of these three innate T cell populations and how they are purposed for antimicrobial defense. Furthermore, we address the mechanisms through which their effector functions are targeted for bacterial control and compare this in human and murine systems. Lastly, we speculate on future roles of these cell types in therapeutic settings such as vaccination. PMID:26124758

  15. A Simple Laboratory Exercise Illustrating Active Transport in Yeast Cells.

    ERIC Educational Resources Information Center

    Stambuk, Boris U.

    2000-01-01

    Describes a simple laboratory activity illustrating the chemiosmotic principles of active transport in yeast cells. Demonstrates the energy coupling mechanism of active a-glucoside uptake by Saccaromyces cerevisiae cells with a colorimetric transport assay using very simple equipment. (Contains 22 references.) (Author/YDS)

  16. Mycoplasma pneumoniae induces cytotoxic activity in guinea pig bronchoalveolar cells

    SciTech Connect

    Kist, M.; Koester, H.; Bredt, W.

    1985-06-01

    Precultured guinea pig alveolar macrophages (AM) and freshly harvested alveolar cells (FHAC) activated by interaction with Mycoplasma pneumoniae were cytotoxic for xenogeneic /sup 75/selenomethionine-labeled tumor target cells. Phagocytosis of whole opsonized or nonopsonized M. pneumoniae cells was more effective in eliciting cytotoxicity than uptake of sonicated microorganisms. The addition of living mycoplasma cells to the assay system enhanced the cytotoxic effect considerably. Target cells were significantly more susceptible to the cytotoxic action of phagocytes if they were coated with mycoplasma antigen or cocultured together with M. pneumoniae. The activation of the phagocytes could be inhibited by 2-deoxy-D-glucose but not by antimicrobial substances suppressing mycoplasma protein synthesis. It was accompanied by /sup 51/Cr release without detectable signs of cell damage. The supernatants of activated cells were cytotoxic for approximately 24 h. Inhibition, release, and cytotoxic activity indicate the necessity of an intact metabolism of the effector cells and suggest a secretion of cytotoxic substances.

  17. Human Liver Stem Cells Suppress T-Cell Proliferation, NK Activity, and Dendritic Cell Differentiation

    PubMed Central

    Bruno, Stefania; Grange, Cristina; Tapparo, Marta; Pasquino, Chiara; Romagnoli, Renato; Dametto, Ennia; Amoroso, Antonio; Tetta, Ciro; Camussi, Giovanni

    2016-01-01

    Human liver stem cells (HLSCs) are a mesenchymal stromal cell-like population resident in the adult liver. Preclinical studies indicate that HLSCs could be a good candidate for cell therapy. The aim of the present study was to evaluate the immunogenicity and the immunomodulatory properties of HLSCs on T-lymphocytes, natural killer cells (NKs), and dendritic cells (DCs) in allogeneic experimental settings. We found that HLSCs inhibited T-cell proliferation by a mechanism independent of cell contact and dependent on the release of prostaglandin E2 (PGE2) and on indoleamine 2,3-dioxygenase activity. When compared with mesenchymal stromal cells (MSCs), HLSCs were more efficient in inhibiting T-cell proliferation. At variance with MSCs, HLSCs did not elicit NK degranulation. Moreover, HLSCs inhibited NK degranulation against K562, a NK-sensitive target, by a mechanism dependent on HLA-G release. When tested on DC generation from monocytes, HLSCs were found to impair DC differentiation and DCs ability to induce T-cell proliferation through PGE2. This study shows that HLSCs have immunomodulatory properties similar to MSCs, but, at variance with MSCs, they do not elicit a NK response. PMID:27127520

  18. Active unjamming of confluent cell layers

    NASA Astrophysics Data System (ADS)

    Marchetti, M. Cristina

    Cell motion inside dense tissues governs many biological processes, including embryonic development and cancer metastasis, and recent experiments suggest that these tissues exhibit collective glassy behavior. Motivated by these observations, we have studied a model of dense tissues that combines self-propelled particle models and vertex models of confluent cell layers. In this model, referred to as self-propelled Voronoi (SPV), cells are described as polygons in a Voronoi tessellation with directed noisy cell motility and interactions governed by a shape energy that incorporates the effects of cell volume incompressibility, contractility and cell-cell adhesion. Using this model, we have demonstrated a new density-independent solid-liquid transition in confluent tissues controlled by cell motility and a cell-shape parameter measuring the interplay of cortical tension and cell-cell adhesion. An important insight of this work is that the rigidity and dynamics of cell layers depends sensitively on cell shape. We have also used the SPV model to test a new method developed by our group to determine cellular forces and tissue stresses from experimentally accessible cell shapes and traction forces, hence providing the spatio-temporal distribution of stresses in motile dense tissues. This work was done with Dapeng Bi, Lisa Manning and Xingbo Yang. MCM was supported by NSF-DMR-1305184 and by the Simons Foundation.

  19. Radiation exposure induces inflammasome pathway activation in immune cells.

    PubMed

    Stoecklein, Veit M; Osuka, Akinori; Ishikawa, Shizu; Lederer, Madeline R; Wanke-Jellinek, Lorenz; Lederer, James A

    2015-02-01

    Radiation exposure induces cell and tissue damage, causing local and systemic inflammatory responses. Because the inflammasome pathway is triggered by cell death and danger-associated molecular patterns, we hypothesized that the inflammasome may signal acute and chronic immune responses to radiation. Using a mouse radiation model, we show that radiation induces a dose-dependent increase in inflammasome activation in macrophages, dendritic cells, NK cells, T cells, and B cells as judged by cleaved caspase-1 detection in cells. Time course analysis showed the appearance of cleaved caspase-1 in cells by day 1 and sustained expression until day 7 after radiation. Also, cells showing inflammasome activation coexpressed the cell surface apoptosis marker annexin V. The role of caspase-1 as a trigger for hematopoietic cell losses after radiation was studied in caspase-1(-/-) mice. We found less radiation-induced cell apoptosis and immune cell loss in caspase-1(-/-) mice than in control mice. Next, we tested whether uric acid might mediate inflammasome activation in cells by treating mice with allopurinol and discovered that allopurinol treatment completely blocked caspase-1 activation in cells. Finally, we demonstrate that radiation-induced caspase-1 activation occurs by a Nod-like receptor family protein 3-independent mechanism because radiation-exposed Nlrp3(-/-) mice showed caspase-1 activation profiles that were indistinguishable from those of wild-type mice. In summary, our data demonstrate that inflammasome activation occurs in many immune cell types following radiation exposure and that allopurinol prevented radiation-induced inflammasome activation. These results suggest that targeting the inflammasome may help control radiation-induced inflammation. PMID:25539818

  20. Dengue Virus Directly Stimulates Polyclonal B Cell Activation

    PubMed Central

    Papa, Michelle Premazzi; de Morais, Ana Theresa Silveira; Peçanha, Ligia Maria Torres; de Arruda, Luciana Barros

    2015-01-01

    Dengue infection is associated to vigorous inflammatory response, to a high frequency of activated B cells, and to increased levels of circulating cross-reactive antibodies. We investigated whether direct infection of B cells would promote activation by culturing primary human B lymphocytes from healthy donors with DENV in vitro. B cells were susceptible, but poorly permissive to infection. Even though, primary B cells cultured with DENV induced substantial IgM secretion, which is a hallmark of polyclonal B cell activation. Notably, DENV induced the activation of B cells obtained from either DENV immune or DENV naïve donors, suggesting that it was not dependent on DENV-specific secondary/memory response. B cell stimulation was dependent on activation of MAPK and CD81. B cells cultured with DENV also secreted IL-6 and presented increased expression of CD86 and HLA-DR, which might contribute to B lymphocyte co-stimulatory function. Indeed, PBMCs, but not isolated B cells, secreted high amounts of IgG upon DENV culture, suggesting that interaction with other cell types in vivo might promote Ig isotype switching and IgG secretion from different B cell clones. These findings suggest that activation signaling pathways triggered by DENV interaction with non-specific receptors on B cells might contribute to the exacerbated response observed in dengue patients. PMID:26656738

  1. Shape control and compartmentalization in active colloidal cells.

    PubMed

    Spellings, Matthew; Engel, Michael; Klotsa, Daphne; Sabrina, Syeda; Drews, Aaron M; Nguyen, Nguyen H P; Bishop, Kyle J M; Glotzer, Sharon C

    2015-08-25

    Small autonomous machines like biological cells or soft robots can convert energy input into control of function and form. It is desired that this behavior emerges spontaneously and can be easily switched over time. For this purpose we introduce an active matter system that is loosely inspired by biology and which we term an active colloidal cell. The active colloidal cell consists of a boundary and a fluid interior, both of which are built from identical rotating spinners whose activity creates convective flows. Similarly to biological cell motility, which is driven by cytoskeletal components spread throughout the entire volume of the cell, active colloidal cells are characterized by highly distributed energy conversion. We demonstrate that we can control the shape of the active colloidal cell and drive compartmentalization by varying the details of the boundary (hard vs. flexible) and the character of the spinners (passive vs. active). We report buckling of the boundary controlled by the pattern of boundary activity, as well as formation of core-shell and inverted Janus phase-separated configurations within the active cell interior. As the cell size is increased, the inverted Janus configuration spontaneously breaks its mirror symmetry. The result is a bubble-crescent configuration, which alternates between two degenerate states over time and exhibits collective migration of the fluid along the boundary. Our results are obtained using microscopic, non-momentum-conserving Langevin dynamics simulations and verified via a phase-field continuum model coupled to a Navier-Stokes equation. PMID:26253763

  2. Shape control and compartmentalization in active colloidal cells

    PubMed Central

    Spellings, Matthew; Engel, Michael; Klotsa, Daphne; Sabrina, Syeda; Drews, Aaron M.; Nguyen, Nguyen H. P.; Bishop, Kyle J. M.; Glotzer, Sharon C.

    2015-01-01

    Small autonomous machines like biological cells or soft robots can convert energy input into control of function and form. It is desired that this behavior emerges spontaneously and can be easily switched over time. For this purpose we introduce an active matter system that is loosely inspired by biology and which we term an active colloidal cell. The active colloidal cell consists of a boundary and a fluid interior, both of which are built from identical rotating spinners whose activity creates convective flows. Similarly to biological cell motility, which is driven by cytoskeletal components spread throughout the entire volume of the cell, active colloidal cells are characterized by highly distributed energy conversion. We demonstrate that we can control the shape of the active colloidal cell and drive compartmentalization by varying the details of the boundary (hard vs. flexible) and the character of the spinners (passive vs. active). We report buckling of the boundary controlled by the pattern of boundary activity, as well as formation of core–shell and inverted Janus phase-separated configurations within the active cell interior. As the cell size is increased, the inverted Janus configuration spontaneously breaks its mirror symmetry. The result is a bubble–crescent configuration, which alternates between two degenerate states over time and exhibits collective migration of the fluid along the boundary. Our results are obtained using microscopic, non–momentum-conserving Langevin dynamics simulations and verified via a phase-field continuum model coupled to a Navier–Stokes equation. PMID:26253763

  3. The DNA methylation profile of activated human natural killer cells.

    PubMed

    Wiencke, John K; Butler, Rondi; Hsuang, George; Eliot, Melissa; Kim, Stephanie; Sepulveda, Manuel A; Siegel, Derick; Houseman, E Andres; Kelsey, Karl T

    2016-05-01

    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. PMID:26967308

  4. Remote Control of T Cell Activation Using Magnetic Janus Particles.

    PubMed

    Lee, Kwahun; Yi, Yi; Yu, Yan

    2016-06-20

    We report a strategy for using magnetic Janus microparticles to control the stimulation of T cell signaling with single-cell precision. To achieve this, we designed Janus particles that are magnetically responsive on one hemisphere and stimulatory to T cells on the other side. By manipulating the rotation and locomotion of Janus particles under an external magnetic field, we could control the orientation of the particle-cell recognition and thereby the initiation of T cell activation. This study demonstrates a step towards employing anisotropic material properties of Janus particles to control single-cell activities without the need of complex magnetic manipulation devices. PMID:27144475

  5. Activation of B cells by antigens on follicular dendritic cells

    PubMed Central

    El Shikh, Mohey Eldin M.; El Sayed, Rania M.; Sukumar, Selvakumar; Szakal, Andras K.; Tew, John G.

    2010-01-01

    A need for antigen-processing and presentation to B cells is not widely appreciated. However, cross-linking of multiple B cell receptors (BCRs) by T-independent antigens delivers a potent signal that induces antibody responses. Such BCR cross-linking also occurs in germinal centers where follicular dendritic cells (FDCs) present multimerized antigens as periodically arranged antigen-antibody complexes (ICs). Unlike T cells that recognize antigens as peptide-MHC complexes, optimal B cell-responses are induced by multimerized FDC-ICs that simultaneously engage multiple BCRs. FDC-FcγRIIB mediates IC-periodicity and FDC-BAFF, -IL-6 and -C4bBP are co-stimulators. Remarkably, specific antibody responses can be induced by FDC-ICs in the absence of T cells, opening up the exciting possibility that people with T cell insufficiencies may be immunized with T-dependent vaccines via FDC-ICs. PMID:20418164

  6. Cell trapping in activated micropores for functional analysis.

    PubMed

    Talasaz, AmirAli H; Powell, Ashley A; Stahl, Patrik; Ronaghi, Mostafa; Jeffrey, Stefanie S; Mindrinos, Michael; Davis, Ronald W

    2006-01-01

    This paper presents a novel device which provides the opportunity to perform high-throughput biochemical assays on different individual cells. In particular, the proposed device is suited to screen the rare cells in biological samples for early stage cancer diagnosis and explore their biochemical functionality. In the process, single cells are precisely positioned and captured in activated micropores. To show the performance of the proposed device, cultured yeast cells and human epithelial circulating tumor cells are successfully captured. PMID:17945673

  7. IL-2 induces STAT4 activation in primary NK cells and NK cell lines, but not in T cells.

    PubMed

    Wang, K S; Ritz, J; Frank, D A

    1999-01-01

    IL-2 exerts potent but distinct functional effects on two critical cell populations of the immune system, T cells and NK cells. Whereas IL-2 leads to proliferation in both cell types, it enhances cytotoxicity primarily in NK cells. In both T cells and NK cells, IL-2 induces the activation of STAT1, STAT3, and STAT5. Given this similarity in intracellular signaling, the mechanism underlying the distinct response to IL-2 in T cells and NK cells is not clear. In this study, we show that in primary NK cells and NK cell lines, in addition to the activation of STAT1 and STAT5, IL-2 induces tyrosine phosphorylation of STAT4, a STAT previously reported to be activated only in response to IL-12 and IFN-alpha. This activation of STAT4 in response to IL-2 is not due to the autocrine production of IL-12 or IFN-alpha. STAT4 activated in response to IL-2 is able to bind to a STAT-binding DNA sequence, suggesting that in NK cells IL-2 is capable of activating target genes through phosphorylation of STAT4. IL-2 induces the activation of Jak2 uniquely in NK cells, which may underlie the ability of IL-2 to activate STAT4 only in these cells. Although the activation of STAT4 in response to IL-2 occurs in primary resting and activated NK cells, it does not occur in primary resting T cells or mitogen-activated T cells. The unique activation of the STAT4-signaling pathway in NK cells may underlie the distinct functional effect of IL-2 on this cell population. PMID:9886399

  8. Senescence of activated stellate cells limits liver fibrosis

    PubMed Central

    Krizhanovsky, Valery; Yon, Monica; Dickins, Ross A.; Hearn, Stephen; Simon, Janelle; Miething, Cornelius; Yee, Herman; Zender, Lars; Lowe, Scott W.

    2011-01-01

    Summary Cellular senescence acts as a potent mechanism of tumor suppression; however, its functional contribution to non-cancer pathologies has not been examined. Here we show that senescent cells accumulate in murine livers treated to produce fibrosis, a precursor pathology to cirrhosis. The senescent cells are derived primarily from activated hepatic stellate cells, which initially proliferate in response to liver damage and produce the extracellular matrix deposited in the fibrotic scar. In mice lacking key senescence regulators, stellate cells continue to proliferate, leading to excessive liver fibrosis. Furthermore, senescent activated stellate cells exhibit gene expression profile consistent with cell cycle exit, reduced secretion of extracellular matrix components, enhanced secretion of extracellular matrix degrading enzymes, and enhanced immune surveillance. Accordingly natural killer cells preferentially kill senescent activated stellate cells in vitro and in vivo, thereby facilitating the resolution of fibrosis. Therefore, the senescence program limits the fibrogenic response to acute tissue damage. PMID:18724938

  9. Mast cells and their activation in lung disease.

    PubMed

    Virk, Harvinder; Arthur, Greer; Bradding, Peter

    2016-08-01

    Mast cells and their activation contribute to lung health via innate and adaptive immune responses to respiratory pathogens. They are also involved in the normal response to tissue injury. However, mast cells are involved in disease processes characterized by inflammation and remodeling of tissue structure. In these diseases mast cells are often inappropriately and chronically activated. There is evidence for activation of mast cells contributing to the pathophysiology of asthma, pulmonary fibrosis, and pulmonary hypertension. They may also play a role in chronic obstructive pulmonary disease, acute respiratory distress syndrome, and lung cancer. The diverse mechanisms through which mast cells sense and interact with the external and internal microenvironment account for their role in these diseases. Newly discovered mechanisms of redistribution and interaction between mast cells, airway structural cells, and other inflammatory cells may offer novel therapeutic targets in these disease processes. PMID:26845625

  10. Cisplatin-induced Casepase-3 activation in different tumor cells

    NASA Astrophysics Data System (ADS)

    Shi, Hua; Li, Xiao; Su, Ting; Zhang, Yu-Hai

    2008-12-01

    Apoptosis plays an essential role in normal organism development which is one of the main types of programmed cell death to help tissues maintain homeostasis. Defective apoptosis can result in cell accumulation and therefore effects on tumor pathogenesis, progression and therapy resistance. A family of proteins, known as caspases, is typically activated in the early stages of apoptosis. Therefore, studying the kinetics of activation of caspases induced by antitumor drugs can contribute to antitumor drug discovery and explanation of the molecular mechanisms. This paper detected the Caspase-3 activity induced by cisplatin in human adenoid cystic carcinoma cell line (ACC-M), human hepatocellular liver carcinoma cell line (HepG2) and human epithelial carcinoma cell line (Hela) with stably expressing ECFP-DEVDDsRed (CD3) probe, a fluorescent probe consisting of Enhanced Cyan Fluorescent Protein (ECFP), red fluorescent protein (DsRed) and a linker with a recognition site of Caspase-3, by using the capillary electrophoresis (CE) and fluorescence resonance energy transfer (FRET) imaging system. Under the same concentration of cisplatin, ACC-M cells responded the most rapidly, and then HepG2 cells and Hela cells, respectively, in the early 30 hours. Later, HepG2 cells represented acceleration in the Caspase-3 activation speed and reached full activation the earliest comparing to other two cell types. The results demonstrated that ACC-M cell is more sensitive than the other two cell types under the treatment of cisplatin.

  11. Immobilization of Pichia pastoris cells containing alcohol oxidase activity

    PubMed Central

    Maleknia, S; Ahmadi, H; Norouzian, D

    2011-01-01

    Background and Objectives The attempts were made to describe the development of a whole cell immobilization of P. pastoris by entrapping the cells in polyacrylamide gel beads. The alcohol oxidase activity of the whole cell Pichia pastoris was evaluated in comparison with yeast biomass production. Materials and Methods Methylotrophic yeast P. pastoris was obtained from Collection of Standard Microorganisms, Department of Bacterial Vaccines, Pasteur Institute of Iran (CSMPI). Stock culture was maintained on YPD agar plates. Alcohol oxidase was strongly induced by addition of 0.5% methanol as the carbon source. The cells were harvested by centrifugation then permeabilized. Finally the cells were immobilized in polyacrylamide gel beads. The activity of alcohol oxidase was determined by method of Tane et al. Results At the end of the logarithmic phase of cell culture, the alcohol oxidase activity of the whole cell P. Pastoris reached the highest level. In comparison, the alcohol oxidase activity was measured in an immobilized P. pastoris when entrapped in polyacrylamide gel beads. The alcohol oxidase activity of cells was induced by addition of 0.5% methanol as the carbon source. The cells were permeabilized by cetyltrimethylammonium bromide (CTAB) and immobilized. CTAB was also found to increase the gel permeability. Alcohol oxidase activity of immobilized cells was then quantitated by ABTS/POD spectrophotometric method at OD 420. There was a 14% increase in alcohol oxidase activity in immobilized cells as compared with free cells. By addition of 2-butanol as a substrate, the relative activity of alcohol oxidase was significantly higher as compared with other substrates added to the reaction media. Conclusion Immobilization of cells could eliminate lengthy and expensive procedures of enzyme separation and purification, protect and stabilize enzyme activity, and perform easy separation of the enzyme from the reaction media. PMID:22530090

  12. Antiviral Regulation in Porcine Monocytic Cells at Different Activation States

    PubMed Central

    Rowland, Raymond R. R.

    2014-01-01

    ABSTRACT Monocytic cells, including macrophages and dendritic cells, exist in different activation states that are critical to the regulation of antimicrobial immunity. Many pandemic viruses are monocytotropic, including porcine reproductive and respiratory syndrome virus (PRRSV), which directly infects subsets of monocytic cells and interferes with antiviral responses. To study antiviral responses in PRRSV-infected monocytic cells, we characterized inflammatory cytokine responses and genome-wide profiled signature genes to investigate response pathways in uninfected and PRRSV-infected monocytic cells at different activation states. Our findings showed suppressed interferon (IFN) production in macrophages in non-antiviral states and an arrest of lipid metabolic pathways in macrophages at antiviral states. Importantly, porcine monocytic cells at different activation states were susceptible to PRRSV and responded differently to viral infection. Based on Gene Ontology (GO) analysis, two approaches were used to potentiate antiviral activity: (i) pharmaceutical modulation of cellular lipid metabolism and (ii) in situ PRRSV replication-competent expression of interferon alpha (IFN-α). Both approaches significantly suppressed exogenous viral infection in monocytic cells. In particular, the engineered IFN-expressing PRRSV strain eliminated exogenous virus infection and sustained cell viability at 4 days postinfection in macrophages. These findings suggest an intricate interaction of viral infection with the activation status of porcine monocytic cells. An understanding and integration of antiviral infection with activation status of monocytic cells may provide a means of potentiating antiviral immunity. IMPORTANCE Activation statuses of monocytic cells, including monocytes, macrophages (Mϕs), and dendritic cells (DCs), are critically important for antiviral immunity. Unfortunately, the activation status of porcine monocytic cells or how cell activation status

  13. Frequent CTLA4-CD28 gene fusion in diverse types of T-cell lymphoma.

    PubMed

    Yoo, Hae Yong; Kim, Pora; Kim, Won Seog; Lee, Seung Ho; Kim, Sangok; Kang, So Young; Jang, Hye Yoon; Lee, Jong-Eun; Kim, Jaesang; Kim, Seok Jin; Ko, Young Hyeh; Lee, Sanghyuk

    2016-06-01

    CTLA4 and CD28 are co-regulatory receptors with opposite roles in T-cell signaling. By RNA sequencing, we identified a fusion between the two genes from partial gene duplication in a case of angioimmunoblastic T-cell lymphoma. The fusion gene, which codes for the extracellular domain of CTLA4 and the cytoplasmic region of CD28, is likely capable of transforming inhibitory signals into stimulatory signals for T-cell activation. Ectopic expression of the fusion transcript in Jurkat and H9 cells resulted in enhanced proliferation and AKT and ERK phosphorylation, indicating activation of downstream oncogenic pathways. To estimate the frequency of this gene fusion in mature T-cell lymphomas, we examined 115 T-cell lymphoma samples of diverse subtypes using reverse transcriptase polymerase chain reaction analysis and Sanger sequencing. We identified the fusion in 26 of 45 cases of angioimmunoblastic T-cell lymphomas (58%), nine of 39 peripheral T-cell lymphomas, not otherwise specified (23%), and nine of 31 extranodal NK/T cell lymphomas (29%). We further investigated the mutation status of 70 lymphoma-associated genes using ultra-deep targeted resequencing for 74 mature T-cell lymphoma samples. The mutational landscape we obtained suggests that T-cell lymphoma results from diverse combinations of multiple gene mutations. The CTLA4-CD28 gene fusion is likely a major contributor to the pathogenesis of T-cell lymphomas and represents a potential target for anti-CTLA4 cancer immunotherapy. PMID:26819049

  14. Frequent CTLA4-CD28 gene fusion in diverse types of T-cell lymphoma

    PubMed Central

    Yoo, Hae Yong; Kim, Pora; Kim, Won Seog; Lee, Seung Ho; Kim, Sangok; Kang, So Young; Jang, Hye Yoon; Lee, Jong-Eun; Kim, Jaesang; Kim, Seok Jin; Ko, Young Hyeh; Lee, Sanghyuk

    2016-01-01

    CTLA4 and CD28 are co-regulatory receptors with opposite roles in T-cell signaling. By RNA sequencing, we identified a fusion between the two genes from partial gene duplication in a case of angioimmunoblastic T-cell lymphoma. The fusion gene, which codes for the extracellular domain of CTLA4 and the cytoplasmic region of CD28, is likely capable of transforming inhibitory signals into stimulatory signals for T-cell activation. Ectopic expression of the fusion transcript in Jurkat and H9 cells resulted in enhanced proliferation and AKT and ERK phosphorylation, indicating activation of downstream oncogenic pathways. To estimate the frequency of this gene fusion in mature T-cell lymphomas, we examined 115 T-cell lymphoma samples of diverse subtypes using reverse transcriptase polymerase chain reaction analysis and Sanger sequencing. We identified the fusion in 26 of 45 cases of angioimmunoblastic T-cell lymphomas (58%), nine of 39 peripheral T-cell lymphomas, not otherwise specified (23%), and nine of 31 extranodal NK/T cell lymphomas (29%). We further investigated the mutation status of 70 lymphoma-associated genes using ultra-deep targeted resequencing for 74 mature T-cell lymphoma samples. The mutational landscape we obtained suggests that T-cell lymphoma results from diverse combinations of multiple gene mutations. The CTLA4-CD28 gene fusion is likely a major contributor to the pathogenesis of T-cell lymphomas and represents a potential target for anti-CTLA4 cancer immunotherapy. PMID:26819049

  15. AUGMENTATION OF MURINE NATURAL KILLER CELL ACTIVITY BY MANGANESE CHLORIDE

    EPA Science Inventory

    Natural Killer (NK) cell activity of spleen cells from male CBA/J mice was augmented by a single parenteral injection of MnCl2 administered 1 day prior to testing by in vitro and in vivo isotope release assays. Increased cytotoxic activity was observed in vitro against both NK-se...

  16. Pacemaker activity resulting from the coupling with nonexcitable cells

    NASA Astrophysics Data System (ADS)

    Jacquemet, Vincent

    2006-07-01

    Fibroblasts are nonexcitable cells that are sometimes coupled with excitable cells (cardiomyocytes). Due to a higher resting potential, these cells may act as a current source or sink and therefore disturb the electrical activity of the surrounding excitable cells. The possible occurrence of spontaneous pacemaker activity resulting from these electrotonic interactions was investigated in a theoretical model of two coupled cells as well as in a multicellular fiber model based on the Courtemanche kinetics. The results indicate that repeated spontaneous activations can be observed after an alteration in the activation and recovery properties of the sodium current (changes in excitability properties), provided that the difference in the resting potential as well as the coupling between the excitable and nonexcitable cells is sufficiently high. This may constitute a mechanism of focal sources triggering arrhythmias such as atrial fibrillation.

  17. GATA3 inhibits GCM1 activity and trophoblast cell invasion.

    PubMed

    Chiu, Yueh Ho; Chen, Hungwen

    2016-01-01

    Development of human placenta involves the invasion of trophoblast cells from anchoring villi into the maternal decidua. Placental transcription factor GCM1 regulates trophoblast cell invasion via transcriptional activation of HtrA4 gene, which encodes a serine protease enzyme. The GATA3 transcription factor regulates trophoblast cell differentiation and is highly expressed in invasive murine trophoblast giant cells. The regulation of trophoblastic invasion by GCM1 may involve novel cellular factors. Here we show that GATA3 interacts with GCM1 and inhibits its activity to suppress trophoblastic invasion. Immunohistochemistry demonstrates that GATA3 and GCM1 are coexpressed in villous cytotrophoblast cells, syncytiotrophoblast layer, and extravillous trophoblast cells of human placenta. Interestingly, GATA3 interacts with GCM1, but not the GCM2 homologue, through the DNA-binding domain and first transcriptional activation domain in GCM1 and the transcriptional activation domains and zinc finger 1 domain in GATA3. While GATA3 did not affect DNA-binding activity of GCM1, it suppressed transcriptional activity of GCM1 and therefore HtrA4 promoter activity. Correspondingly, GATA3 knockdown elevated HtrA4 expression in BeWo and JEG-3 trophoblast cell lines and enhanced the invasion activities of both lines. This study uncovered a new GATA3 function in placenta as a negative regulator of GCM1 activity and trophoblastic invasion. PMID:26899996

  18. GATA3 inhibits GCM1 activity and trophoblast cell invasion

    PubMed Central

    Chiu, Yueh Ho; Chen, Hungwen

    2016-01-01

    Development of human placenta involves the invasion of trophoblast cells from anchoring villi into the maternal decidua. Placental transcription factor GCM1 regulates trophoblast cell invasion via transcriptional activation of HtrA4 gene, which encodes a serine protease enzyme. The GATA3 transcription factor regulates trophoblast cell differentiation and is highly expressed in invasive murine trophoblast giant cells. The regulation of trophoblastic invasion by GCM1 may involve novel cellular factors. Here we show that GATA3 interacts with GCM1 and inhibits its activity to suppress trophoblastic invasion. Immunohistochemistry demonstrates that GATA3 and GCM1 are coexpressed in villous cytotrophoblast cells, syncytiotrophoblast layer, and extravillous trophoblast cells of human placenta. Interestingly, GATA3 interacts with GCM1, but not the GCM2 homologue, through the DNA-binding domain and first transcriptional activation domain in GCM1 and the transcriptional activation domains and zinc finger 1 domain in GATA3. While GATA3 did not affect DNA-binding activity of GCM1, it suppressed transcriptional activity of GCM1 and therefore HtrA4 promoter activity. Correspondingly, GATA3 knockdown elevated HtrA4 expression in BeWo and JEG-3 trophoblast cell lines and enhanced the invasion activities of both lines. This study uncovered a new GATA3 function in placenta as a negative regulator of GCM1 activity and trophoblastic invasion. PMID:26899996

  19. Signal transduction pathways in mast cell granule-mediated endothelial cell activation.

    PubMed Central

    Chi, Luqi; Stehno-Bittel, Lisa; Smirnova, Irina; Stechschulte, Daniel J; Dileepan, Kottarappat N

    2003-01-01

    BACKGROUND: We have previously shown that incubation of human endothelial cells with mast cell granules results in potentiation of lipopolysaccharide-induced production of interleukin-6 and interleukin-8. AIMS: The objective of the present study was to identify candidate molecules and signal transduction pathways involved in the synergy between mast cell granules and lipopolysaccharide on endothelial cell activation. METHODS: Human umbilical vein endothelial cells were incubated with rat mast cell granules in the presence and absence of lipopolysaccharide, and IL-6 production was quantified. The status of c-Jun amino-terminal kinase and extracellular signal-regulated kinase 1/2 activation, nuclear factor-kappaB translocation and intracellular calcium levels were determined to identify the mechanism of synergy between mast cell granules and lipopolysaccaride. RESULTS: Mast cell granules induced low levels of interleukin-6 production by endothelial cells, and this effect was markedly enhanced by lipopolysaccharide. The results revealed that both serine proteases and histamine present in mast cell granules were involved in this activation process. Mast cell granules increased intracellular calcium, and activated c-Jun amino-terminal kinase and extracellular signal-regulated kinase 1/2. The combination of lipopolysaccharide and mast cell granules prolonged c-Jun amino-terminal kinase activity beyond the duration of induction by either stimulant alone and was entirely due to active proteases. However, both proteases and histamine contributed to calcium mobilization and extracellular signal-regulated kinase 1/2 activation. The nuclear translocation of nuclear factor-kappaB proteins was of greater magnitude in endothelial cells treated with the combination of mast cell granules and lipopolysaccharide. CONCLUSIONS:Mast cell granule serine proteases and histamine can amplify lipopolysaccharide-induced endothelial cell activation, which involves calcium mobilization, mitogen-activated

  20. Imaging the coordination of multiple signaling activities in living cells

    PubMed Central

    Welch, Christopher M.; Elliott, Hunter; Danuser, Gaudenz; Hahn, Klaus M.

    2013-01-01

    Preface Cellular signal transduction occurs in complex and redundant interaction networks that are best examined at the level of single cells by simultaneously monitoring the activation dynamics of multiple components. Recent advances in biosensor technology have made it possible to visualize and quantify the activation of multiple network nodes in the same living cell. The precision and scope of this approach has been greatly extended by novel computational approaches to determine the relationships between different networks, studied in separate cells. PMID:22016058

  1. Effects of Neuroendocrine CB1 Activity on Adult Leydig Cells

    PubMed Central

    Cobellis, Gilda; Meccariello, Rosaria; Chianese, Rosanna; Chioccarelli, Teresa; Fasano, Silvia; Pierantoni, Riccardo

    2016-01-01

    Endocannabinoids control male reproduction acting at central and local level via cannabinoid receptors. The cannabinoid receptor CB1 has been characterized in the testis, in somatic and germ cells of mammalian and non-mammalian animal models, and its activity related to Leydig cell differentiation, steroidogenesis, spermiogenesis, sperm quality, and maturation. In this short review, we provide a summary of the insights concerning neuroendocrine CB1 activity in male reproduction focusing on adult Leydig cell ontogenesis and steroid biosynthesis. PMID:27375550

  2. Calcium alloy as active material in secondary electrochemical cell

    DOEpatents

    Roche, Michael F.; Preto, Sandra K.; Martin, Allan E.

    1976-01-01

    Calcium alloys such as calcium-aluminum and calcium-silicon, are employed as active material within a rechargeable negative electrode of an electrochemical cell. Such cells can use a molten salt electrolyte including calcium ions and a positive electrode having sulfur, sulfides, or oxides as active material. The calcium alloy is selected to prevent formation of molten calcium alloys resulting from reaction with the selected molten electrolytic salt at the cell operating temperatures.

  3. Effects of Neuroendocrine CB1 Activity on Adult Leydig Cells.

    PubMed

    Cobellis, Gilda; Meccariello, Rosaria; Chianese, Rosanna; Chioccarelli, Teresa; Fasano, Silvia; Pierantoni, Riccardo

    2016-01-01

    Endocannabinoids control male reproduction acting at central and local level via cannabinoid receptors. The cannabinoid receptor CB1 has been characterized in the testis, in somatic and germ cells of mammalian and non-mammalian animal models, and its activity related to Leydig cell differentiation, steroidogenesis, spermiogenesis, sperm quality, and maturation. In this short review, we provide a summary of the insights concerning neuroendocrine CB1 activity in male reproduction focusing on adult Leydig cell ontogenesis and steroid biosynthesis. PMID:27375550

  4. Microwave-induced thermogenetic activation of single cells

    SciTech Connect

    Safronov, N. A.; Fedotov, I. V.; Ermakova, Yu. G.; Matlashov, M. E.; Belousov, V. V.; Sidorov-Biryukov, D. A.; Fedotov, A. B.; Zheltikov, A. M.

    2015-04-20

    Exposure to a microwave field is shown to enable thermogenetic activation of individual cells in a culture of cell expressing thermosensitive ion channels. Integration of a microwave transmission line with an optical fiber and a diamond quantum thermometer has been shown to allow thermogenetic single-cell activation to be combined with accurate local online temperature measurements based on an optical detection of electron spin resonance in nitrogen–vacancy centers in diamond.

  5. Effects of dexamethasone on palate mesenchymal cell phospholipase activity

    SciTech Connect

    Bulleit, R.F.; Zimmerman, E.F.

    1984-09-15

    Corticosteroids will induce cleft palate in mice. One suggested mechanism for this effect is through inhibition of phospholipase activity. This hypothesis was tested by measuring the effects of dexamethasone, a synthetic corticosteroid, on phospholipase activity in cultures of palate mesenchymal cells. Palate mesenchymal cells were prelabeled with (3H)arachidonic acid. The cells were subsequently treated with various concentrations of dexamethasone. Concurrently, cultures of M-MSV-transformed 3T3 cells were prepared identically. After treatment, phospholipase activity was stimulated by the addition of serum or epidermal growth factor (EGF), and radioactivity released into the medium was taken as a measure of phospholipase activity. Dexamethasone (1 X 10(-5) or 1 X 10(-4) M) could inhibit serum-stimulated phospholipase activity in transformed 3T3 cells after 1 to 24 hr of treatment. However, no inhibition of activity was measured in palate mesenchymal cells following this period of treatment. Not until 120 hr of treatment with dexamethasone (1 X 10(-4) M) was any significant inhibition of serum-stimulated phospholipase activity observed in palate mesenchymal cells. When EGF was used to stimulate phospholipase activity, dexamethasone (1 X 10(-5) M) caused an increase in phospholipase activity in palate mesenchymal cells. These observations suggested that phospholipase in transformed 3T3 cells was sensitive to inhibition by dexamethasone. However, palate mesenchymal cell phospholipase is only minimally sensitive to dexamethasone, and in certain instances can be enhanced. These results cannot support the hypothesis that corticosteroids mediate their teratogenic effect via inhibition of phospholipase activity.

  6. Mitogen-activated Tasmanian devil blood mononuclear cells kill devil facial tumour disease cells.

    PubMed

    Brown, Gabriella K; Tovar, Cesar; Cooray, Anne A; Kreiss, Alexandre; Darby, Jocelyn; Murphy, James M; Corcoran, Lynn M; Bettiol, Silvana S; Lyons, A Bruce; Woods, Gregory M

    2016-08-01

    Devil facial tumour disease (DFTD) is a transmissible cancer that has brought the host species, the Tasmanian devil, to the brink of extinction. The cancer cells avoid allogeneic immune recognition by downregulating cell surface major histocompatibility complex (MHC) I expression. This should prevent CD8(+) T cell, but not natural killer (NK) cell, cytotoxicity. The reason why NK cells, normally reactive to MHC-negative cells, are not activated to kill DFTD cells has not been determined. The immune response of wild devils to DFTD, if it occurs, is uncharacterised. To investigate this, we tested 12 wild devils with DFTD, and found suggestive evidence of low levels of antibodies against DFTD cells in one devil. Eight of these devils were also analysed for cytotoxicity, however, none showed evidence for cytotoxicity against cultured DFTD cells. To establish whether mimicking activation of antitumour responses could induce cytotoxic activity against DFTD, Tasmanian devil peripheral blood mononuclear cells (PBMCs) were treated with either the mitogen Concanavalin A, the Toll-like receptor agonist polyinosinic:polycytidylic acid or recombinant Tasmanian devil IL-2. All induced the PBMC cells to kill cultured DFTD cells, suggesting that activation does not occur after encounter with DFTD cells in vivo, but can be induced. The identification of agents that activate cytotoxicity against DFTD target cells is critical for developing strategies to protect against DFTD. Such agents could function as adjuvants to induce functional immune responses capable of targeting DFTD cells and tumours in vivo. PMID:27089941

  7. Selective activation of functional suppressor cells by human seminal fluid.

    PubMed Central

    Witkin, S S

    1986-01-01

    The ability of seminal fluid (SF) to induce suppressor cell activity from peripheral blood mononuclear cells (PBMN) was examined. PBMN were incubated with SF for 48 h, washed to remove SF components, treated with mitomycin C (mit C) and co-cultured with Raji cells, a lymphoblastoid cell line. Raji cell proliferation was inhibited by SF-treated PBMN proportionally to SF concentration. SF (50-200 micrograms), mit C-treated Raji cells or mit C-treated PBMN pre-incubated with phytohaemagglutinin were without effect on Raji cell growth. Suppressor T lymphocytes generated by incubation of PBMN with concanavalin A inhibited Raji cells to the same extent as did SF-treated PBMN. All activity was lost following heating at 56 degrees C for 30 min; freezing and thawing reduced the ability of SF to induce suppression by 50%. Dialysis of SF or treatment with antibody to prostaglandin E2 led to a 50% reduction in suppression. PMID:2943541

  8. Platelet activating factor: regulation by mast cells and aspirin.

    PubMed

    Denburg, J A; Williams, D B; Kinlough-Rathbone, R L; Cazenave, J P; Bienenstock, J

    1984-02-01

    We have investigated some aspects of the regulation of production of rat platelet activating factor (PAF)2 in vitro. Suspensions of unseparated (PLC1), mast cell-depleted (PLC2), or mast cell (MC)-enriched rat peritoneal lavage cells (PLC) were analyzed for PAF content by extraction at alkaline pH. PAF activity extracted from PLC1 varied inversely with viable cell concentration: at 1 X 10(6) cells/ml, 32 +/- 9.3 PAF units, decreasing to 11.2 +/- 9.5 units at 10 X 10(6) cells/ml, and no activity at higher concentrations. Incubation of PLC1 in Tyrode's buffer or acetylsalicylic acid (ASA), but not salicylate, resulted in a time-dependent loss of PAF activity. Mean PAF activity of PLC2 was similar to that in PLC1, while no PAF activity was extractable from MC. Co-incubation with MC extracts inhibited PAF activity of PLC1 extracts in a dose-dependent fashion. Ultracentrifugation of PAF-containing samples led to a loss of all PAF activity in PLC1 extracts, suggesting the association of PAF activity with subcellular components. PAF appears to be derived from a non-MC population of rat PLC, is not extractable from rat PLC in the presence of ASA and is inhibited by MC extracts. These studies suggest that ASA regulates PAF availability unrelated to its effect on cyclooxygenase and that MC membrane products directly inhibit PAF activity from rat PLC. PMID:6711391

  9. Effect of substrate mechanical properties on T cell activation

    NASA Astrophysics Data System (ADS)

    Hui, King; Upadhyaya, Arpita

    2013-03-01

    T cell activation is a key process in cell-mediated immunity, and engagement of T cell receptors by peptides on antigen presenting cells leads to activation of signaling cascades as well as cytoskeletal reorganization and large scale membrane deformations. While significant advances have been made in understanding the biochemical signaling pathways, the effects imposed by the physical environment and the role of mechanical forces on cell activation are not well understood. In this study, we have used anti-CD3 coated elastic polyacrylamide gels as stimulatory substrates to enable the spreading of Jurkat T cells and the measurement of cellular traction forces. We have investigated the effect of substrate stiffness on the dynamics of T cell spreading and cellular force generation. We found that T cells display more active and sustained edge dynamics on softer gels and that they exert increased traction stresses with increasing gel stiffness. A dynamic actin cytoskeleton was required to maintain the forces generated during activation, as inferred from small molecule inhibition experiments. Our results indicate an important role for physical properties of the antigen presenting cell as well as cytoskeleton-driven forces in signaling activation.

  10. BMP2 Transfer to Neighboring Cells and Activation of Signaling.

    PubMed

    Alborzinia, Hamed; Shaikhkarami, Marjan; Hortschansky, Peter; Wölfl, Stefan

    2016-09-01

    Morphogen gradients and concentration are critical features during early embryonic development and cellular differentiation. Previously we reported the preparation of biologically active, fluorescently labeled BMP2 and quantitatively analyzed their binding to the cell surface and followed BMP2 endocytosis over time on the level of single endosomes. Here we show that this internalized BMP2 can be transferred to neighboring cells and, moreover, also activates downstream BMP signaling in adjacent cells, indicated by Smad1/5/8 phosphorylation and activation of the downstream target gene id1. Using a 3D matrix to modulate cell-cell contacts in culture we could show that direct cell-cell contact significantly increased BMP2 transfer. Using inhibitors of vesicular transport, transfer was strongly inhibited. Interestingly, cotreatment with the physiological BMP inhibitor Noggin increased BMP2 uptake and transfer, albeit activation of Smad signaling in neighboring cells was completely suppressed. Our findings present a novel and interesting mechanism by which morphogens such as BMP2 can be transferred between cells and how this is modulated by BMP antagonists such as Noggin, and how this influences activation of Smad signaling by BMP2 in neighboring cells. PMID:27306974

  11. Functional Implications of Plasma Membrane Condensation for T Cell Activation

    PubMed Central

    Quinn, Carmel M.; Engelhardt, Karin; Williamson, David; Grewal, Thomas; Jessup, Wendy; Harder, Thomas; Gaus, Katharina

    2008-01-01

    The T lymphocyte plasma membrane condenses at the site of activation but the functional significance of this receptor-mediated membrane reorganization is not yet known. Here we demonstrate that membrane condensation at the T cell activation sites can be inhibited by incorporation of the oxysterol 7-ketocholesterol (7KC), which is known to prevent the formation of raft-like liquid-ordered domains in model membranes. We enriched T cells with 7KC, or cholesterol as control, to assess the importance of membrane condensation for T cell activation. Upon 7KC treatment, T cell antigen receptor (TCR) triggered calcium fluxes and early tyrosine phosphorylation events appear unaltered. However, signaling complexes form less efficiently on the cell surface, fewer phosphorylated signaling proteins are retained in the plasma membrane and actin restructuring at activation sites is impaired in 7KC-enriched cells resulting in compromised downstream activation responses. Our data emphasizes lipids as an important medium for the organization at T cell activation sites and strongly indicates that membrane condensation is an important element of the T cell activation process. PMID:18509459

  12. Activation-induced necroptosis contributes to B-cell lymphopenia in active systemic lupus erythematosus

    PubMed Central

    Fan, H; Liu, F; Dong, G; Ren, D; Xu, Y; Dou, J; Wang, T; Sun, L; Hou, Y

    2014-01-01

    B-cell abnormality including excessive activation and lymphopenia is a central feature of systemic lupus erythematosus (SLE). Although activation threshold, auto-reaction and death of B cells can be affected by intrinsical and/or external signaling, the underlying mechanisms are unclear. Herein, we demonstrate that co-activation of Toll-like receptor 7 (TLR7) and B-cell receptor (BCR) pathways is a core event for the survival/dead states of B cells in SLE. We found that the mortalities of CD19+CD27- and CD19+IgM+ B-cell subsets were increased in the peripheral blood mononuclear cells (PBMCs) of SLE patients. The gene microarray analysis of CD19+ B cells from active SLE patients showed that the differentially expressed genes were closely correlated to TLR7, BCR, apoptosis, necroptosis and immune pathways. We also found that co-activation of TLR7 and BCR could trigger normal B cells to take on SLE-like B-cell characters including the elevated viability, activation and proliferation in the first 3 days and necroptosis in the later days. Moreover, the necroptotic B cells exhibited mitochondrial dysfunction and hypoxia, along with the elevated expression of necroptosis-related genes, consistent with that in both SLE B-cell microarray and real-time PCR verification. Expectedly, pretreatment with the receptor-interacting protein kinase 1 (RIPK1) inhibitor Necrostatin-1, and not the apoptosis inhibitor zVAD, suppressed B-cell death. Importantly, B cells from additional SLE patients also significantly displayed high expression levels of necroptosis-related genes compared with those from healthy donors. These data indicate that co-activation of TLR7 and BCR pathways can promote B cells to hyperactivation and ultimately necroptosis. Our finding provides a new explanation on B-cell lymphopenia in active SLE patients. These data suggest that extrinsic factors may increase the intrinsical abnormality of B cells in SLE patients. PMID:25210799

  13. Mast cells and dendritic cells form synapses that facilitate antigen transfer for T cell activation

    PubMed Central

    Carroll-Portillo, Amanda; Cannon, Judy L.; te Riet, Joost; Holmes, Anna; Kawakami, Yuko; Kawakami, Toshiaki; Cambi, Alessandra

    2015-01-01

    Mast cells (MCs) produce soluble mediators such as histamine and prostaglandins that are known to influence dendritic cell (DC) function by stimulating maturation and antigen processing. Whether direct cell–cell interactions are important in modulating MC/DC function is unclear. In this paper, we show that direct contact between MCs and DCs occurs and plays an important role in modulating the immune response. Activation of MCs through FcεRI cross-linking triggers the formation of stable cell–cell interactions with immature DCs that are reminiscent of the immunological synapse. Direct cellular contact differentially regulates the secreted cytokine profile, indicating that MC modulation of DC populations is influenced by the nature of their interaction. Synapse formation requires integrin engagement and facilitates the transfer of internalized MC-specific antigen from MCs to DCs. The transferred material is ultimately processed and presented by DCs and can activate T cells. The physiological outcomes of the MC–DC synapse suggest a new role for intercellular crosstalk in defining the immune response. PMID:26304724

  14. Tubular solid oxide fuel cell demonstration activities

    SciTech Connect

    Veyo, S.E.

    1995-08-01

    The development of a viable fuel cell driven electrical power generation system involves not only the development of cell and stack technology, but also the development of the overall system concept, the strategy for control, and the ancillary subsystems. The design requirements used to guide system development must reflect a customer focus in order to evolve a commercial product. In order to obtain useful customer feedback, Westinghouse has practiced the deployment with customers of fully integrated, automatically controlled, packaged solid oxide fuel cell power generation systems. These field units have served to demonstrate to customers first hand the beneficial attributes of the SOFC, to expose deficiencies through experience in order to guide continued development, and to garner real world feedback and data concerning not only cell and stack parameters, but also transportation, installation, permitting and licensing, start-up and shutdown, system alarming, fault detection, fault response, and operator interaction.

  15. Interleukin-7 and Toll-Like Receptor 7 Induce Synergistic B Cell and T Cell Activation

    PubMed Central

    Bikker, Angela; Kruize, Aike A.; van der Wurff-Jacobs, Kim M. G.; Peters, Rogier P.; Kleinjan, Marije; Redegeld, Frank; de Jager, Wilco; Lafeber, Floris P. J. G.; van Roon, Joël A. G.

    2014-01-01

    Objectives To investigate the potential synergy of IL-7-driven T cell-dependent and TLR7-mediated B cell activation and to assess the additive effects of monocyte/macrophages in this respect. Methods Isolated CD19 B cells and CD4 T cells from healthy donors were co-cultured with TLR7 agonist (TLR7A, Gardiquimod), IL-7, or their combination with or without CD14 monocytes/macrophages (T/B/mono; 1 : 1 : 0,1). Proliferation was measured using 3H-thymidine incorporation and Ki67 expression. Activation marker (CD19, HLA-DR, CD25) expression was measured by FACS analysis. Immunoglobulins were measured by ELISA and release of cytokines was measured by Luminex assay. Results TLR7-induced B cell activation was not associated with T cell activation. IL-7-induced T cell activation alone and together with TLR7A synergistically increased numbers of both proliferating (Ki67+) B cells and T cells, which was further increased in the presence of monocytes/macrophages. This was associated by up regulation of activation markers on B cells and T cells. Additive or synergistic induction of production of immunoglobulins by TLR7 and IL-7 was associated by synergistic induction of T cell cytokines (IFNγ, IL-17A, IL-22), which was only evident in the presence of monocytes/macrophages. Conclusions IL-7-induced CD4 T cell activation and TLR7-induced B cell activation synergistically induce T helper cell cytokine and B cell immunoglobulin production, which is critically dependent on monocytes/macrophages. Our results indicate that previously described increased expression of IL-7 and TLR7 together with increased numbers of macrophages at sites of inflammation in autoimmune diseases like RA and pSS significantly contributes to enhanced lymphocyte activation. PMID:24740301

  16. Nfil3-independent lineage maintenance and antiviral response of natural killer cells.

    PubMed

    Firth, Matthew A; Madera, Sharline; Beaulieu, Aimee M; Gasteiger, Georg; Castillo, Eliseo F; Schluns, Kimberly S; Kubo, Masato; Rothman, Paul B; Vivier, Eric; Sun, Joseph C

    2013-12-16

    Development of the natural killer (NK) cell lineage is dependent on the transcription factor Nfil3 (or E4BP4), which is thought to act downstream of IL-15 signaling. Nfil3-deficient mice lack NK cells, whereas other lymphocyte lineages (B, T, and NKT cells) remain largely intact. We report the appearance of Ly49H-expressing NK cells in Nfil3(-/-) mice infected with mouse cytomegalovirus (MCMV) or recombinant viruses expressing the viral m157 glycoprotein. Nfil3(-/-) NK cells at the peak of antigen-driven expansion were functionally similar to NK cells from infected wild-type mice with respect to IFN-γ production and cytotoxicity, and could comparably produce long-lived memory NK cells that persisted in lymphoid and nonlymphoid tissues for >60 d. We demonstrate that generation and maintenance of NK cell memory is an Nfil3-independent but IL-15-dependent process. Furthermore, specific ablation of Nfil3 in either immature NK cells in the bone marrow or mature peripheral NK cells had no observable effect on NK cell lineage maintenance or homeostasis. Thus, expression of Nfil3 is crucial only early in the development of NK cells, and signals through activating receptors and proinflammatory cytokines during viral infection can bypass the requirement for Nfil3, promoting the proliferation and long-term survival of virus-specific NK cells. PMID:24277151

  17. Cutting edge: cell surface linker for activation of T cells is recruited to microclusters and is active in signaling.

    PubMed

    Balagopalan, Lakshmi; Barr, Valarie A; Kortum, Robert L; Park, Anna K; Samelson, Lawrence E

    2013-04-15

    A controversy has recently emerged regarding the location of the cellular pool of the adapter linker for activation of T cells (LAT) that participates in propagation of signals downstream of the TCR. In one model phosphorylation and direct recruitment of cell surface LAT to activation-induced microclusters is critical for T cell activation, whereas in the other model vesicular, but not surface, LAT participates in these processes. By using a chimeric version of LAT that can be tracked via an extracellular domain, we provide evidence that LAT located at the cell surface can be recruited efficiently to activation-induced microclusters within seconds of TCR engagement. Importantly, we also demonstrate that this pool of LAT at the plasma membrane is rapidly phosphorylated. Our results provide support for the model in which the cell utilizes LAT from the cell surface for rapid responses to TCR stimulation. PMID:23487428

  18. T Cell Activation Thresholds are Affected by Gravitational

    NASA Technical Reports Server (NTRS)

    Adams, Charley; Gonzalez, M.; Nelman-Gonzalez, M.

    1999-01-01

    T cells stimulated in space flight by various mitogenic signals show a dramatic reduction in proliferation and expression of early activation markers. Similar results are also obtained in a ground based model of microgravity, clinorotation, which provides a vector-averaged reduction of the apparent gravity on cells without significant shear force. Here we demonstrate that T cell inhibition is due to an increase in the required threshold for activation. Dose response curves indicate that cells activated during clinorotation require higher stimulation to achieve the same level of activation, as measured by CD69 expression. Interleukin 2 receptor expression, and DNA synthesis. The amount of stimulation necessary for 50% activation is 5 fold in the clinostat relative to static. Correlation of TCR internalization with activation also exhibit a dramatic right shift in clinorotation, demonstrating unequivocally that signal transduction mechanism independent of TCR triggering account for the increased activation threshold. Previous results from space flight experiments are consistent with the dose response curves obtained for clinorotation. Activation thresholds are important aspects of T cell memory, autoimmunity and tolerance Clinorotation is a useful, noninvasive tool for the study of cellular and biochemical event regulating T cell activation threshold and the effects of gravitation forces on these systems.

  19. Balance of inflammatory pathways and interplay of immune cells in the liver during homeostasis and injury

    PubMed Central

    Baeck, Christer; Tacke, Frank

    2014-01-01

    Multiple potentially harmful stimuli challenge the liver, the chief metabolic and detoxifying organ of the human body. Due to its central anatomical location, continuous blood flow from the gastrointestinal tract through the hepatic sinusoids allows the metabolically active hepatocytes, the non-parenchymal cells and the various immune cell populations residing and patrolling in the liver to interact with antigens and microbiological components coming from the intestine. Cytokines are key mediators within the complex interplay of intrahepatic immune cells and hepatocytes, because they can activate effector functions of immune cells as well as hepatocytic intracellular signaling pathways controlling cellular homeostasis. Kupffer cells and liver-infiltrating monocyte-derived macrophages are primary sources of cytokines such as tumor necrosis factor (TNF). The liver is also enriched in natural killer (NK) and natural killer T (NKT) cells, which fulfill functions in pathogen defense, T cell recruitment and modulation of fibrogenic responses. TNF can activate specific intracellular pathways in hepatocytes that influence cell fate in different manners, e.g. pro-apoptotic signals via the caspase cascade, but also survival pathways, namely the nuclear factor (NF)-kappaB pathway. NF-kappaB regulates important functions in liver physiology and pathology. The exact dissection of the contribution of recruited and resident immune cells, their soluble cytokine and chemokine mediators and the intracellular hepatocytic response in liver homeostasis and injury could potentially identify novel targets for the treatment of acute and chronic liver disease, liver fibrosis or cirrhosis. PMID:26417243

  20. Retinal Pigment Epithelial Cell Line Suppression of Phagolysosome Activation

    PubMed Central

    Taylor, AW; Dixit, S; Yu, J

    2015-01-01

    The eye is an immune privileged tissue with multiple mechanisms of immunosuppression to protect the light gathering tissues from the damage of inflammation. One of theses mechanisms involves retinal pigment epithelial cell suppression of phagosome activation in macrophages. The objective of this work is to determine if the human RPE cell line ARPE-19 is capable of suppressing the activation of the phagolysosome in macrophages in a manner similar to primary RPE. The conditioned media of RPE eyecups, sub-confluent, just confluent cultures, or established confluent cultures of human ARPE-19 cells were generated. These condition media were used to treat macrophages phagocytizing pHrodo bioparticles. After 24 hours incubation the macrophages were imaged by fluorescent microscopy, and fluorescence was measured. The fluorescent intensity is proportional to the amount of bioparticles phagocytized and are in an activated phagolysosome. The conditioned media of in situ mouse RPE eyecups significantly suppressed the activation of phagolysosome. The conditioned media from cultures of human ARPE-19 cells, grown to sub-confluence (50%) or grown to confluence had no effect on phagolysosome activation. In contrast, the conditioned media from established confluent cultures significantly suppressed phagolysosome activation. The neuropeptides alpha-MSH and NPY were depleted from the conditioned media of established confluent ARPE-19 cell cultures. This depleted conditioned media had diminished suppression of phagolysosome activation while promoting macrophage cell death. In addition, the condition media from cultures of ARPE-19 monolayers wounded with a bisecting scrape was diminished in suppressing phagolysosome activation. This technical report suggests that like primary RPE monolayers, established confluent cultures of ARPE-19 cells produce soluble factors that suppress the activation of macrophages, and can be used to study the molecular mechanisms of retinal immunobiology. In

  1. Activation of human inflammatory cells by secreted phospholipases A2.

    PubMed

    Triggiani, Massimo; Granata, Francescopaolo; Frattini, Annunziata; Marone, Gianni

    2006-11-01

    Secreted phospholipases A(2) (sPLA(2)s) are enzymes detected in serum and biological fluids of patients with various inflammatory, autoimmune and allergic disorders. Different isoforms of sPLA(2)s are expressed and released by human inflammatory cells, such as neutrophils, eosinophils, T cells, monocytes, macrophages and mast cells. sPLA(2)s generate arachidonic acid and lysophospholipids thus contributing to the production of bioactive lipid mediators in inflammatory cells. However, sPLA(2)s also activate human inflammatory cells by mechanisms unrelated to their enzymatic activity. Several human and non-human sPLA(2)s induce degranulation of mast cells, neutrophils and eosinophils and activate exocytosis in macrophages. In addition some, but not all, sPLA(2) isoforms promote cytokine and chemokine production from macrophages, neutrophils, eosinophils, monocytes and endothelial cells. These effects are primarily mediated by binding of sPLA(2)s to specific membrane targets (heparan sulfate proteoglycans, M-type, N-type or mannose receptors) expressed on effector cells. Thus, sPLA(2)s may play an important role in the initiation and amplification of inflammatory reactions by at least two mechanisms: production of lipid mediators and direct activation of inflammatory cells. Selective inhibitors of sPLA(2)-enzymatic activity and specific antagonists of sPLA(2) receptors are current being tested for pharmacological treatment of inflammatory and autoimmune diseases. PMID:16952481

  2. Active elastic dimers: cells moving on rigid tracks.

    PubMed

    Lopez, J H; Das, Moumita; Schwarz, J M

    2014-09-01

    Experiments suggest that the migration of some cells in the three-dimensional extracellular matrix bears strong resemblance to one-dimensional cell migration. Motivated by this observation, we construct and study a minimal one-dimensional model cell made of two beads and an active spring moving along a rigid track. The active spring models the stress fibers with their myosin-driven contractility and α-actinin-driven extendability, while the friction coefficients of the two beads describe the catch and slip-bond behaviors of the integrins in focal adhesions. In the absence of active noise, net motion arises from an interplay between active contractility (and passive extendability) of the stress fibers and an asymmetry between the front and back of the cell due to catch-bond behavior of integrins at the front of the cell and slip-bond behavior of integrins at the back. We obtain reasonable cell speeds with independently estimated parameters. We also study the effects of hysteresis in the active spring, due to catch-bond behavior and the dynamics of cross linking, and the addition of active noise on the motion of the cell. Our model highlights the role of α-actinin in three-dimensional cell motility and does not require Arp2/3 actin filament nucleation for net motion. PMID:25314473

  3. Active elastic dimers: Cells moving on rigid tracks

    NASA Astrophysics Data System (ADS)

    Lopez, J. H.; Das, Moumita; Schwarz, J. M.

    2014-09-01

    Experiments suggest that the migration of some cells in the three-dimensional extracellular matrix bears strong resemblance to one-dimensional cell migration. Motivated by this observation, we construct and study a minimal one-dimensional model cell made of two beads and an active spring moving along a rigid track. The active spring models the stress fibers with their myosin-driven contractility and α-actinin-driven extendability, while the friction coefficients of the two beads describe the catch and slip-bond behaviors of the integrins in focal adhesions. In the absence of active noise, net motion arises from an interplay between active contractility (and passive extendability) of the stress fibers and an asymmetry between the front and back of the cell due to catch-bond behavior of integrins at the front of the cell and slip-bond behavior of integrins at the back. We obtain reasonable cell speeds with independently estimated parameters. We also study the effects of hysteresis in the active spring, due to catch-bond behavior and the dynamics of cross linking, and the addition of active noise on the motion of the cell. Our model highlights the role of α-actinin in three-dimensional cell motility and does not require Arp2/3 actin filament nucleation for net motion.

  4. Evolution of nonclassical MHC-dependent invariant T cells

    PubMed Central

    Edholm, Eva-Stina; Grayfer, Leon; Robert, Jacques

    2014-01-01

    TCR-mediated specific recognition of antigenic peptides in the context of classical MHC molecules is a cornerstone of adaptive immunity of jawed vertebrate. Ancillary to these interactions, the T cell repertoire also includes unconventional T cells that recognize endogenous and/or exogenous antigens in a classical MHC-unrestricted manner. Among these, the mammalian nonclassical MHC class I-restricted invariant T cell (iT) subsets, such as iNKT and MAIT cells, are now believed to be integral to immune response initiation as well as in orchestrating subsequent adaptive immunity. Until recently the evolutionary origins of these cells were unknown. Here we review our current understanding of a nonclassical MHC class I-restricted iT cell population in the amphibian Xenopus laevis. Parallels with the mammalian iNKT and MAIT cells underline the crucial biological roles of these evolutionarily ancient immune subsets. PMID:25117267

  5. The effects of trastuzumab on the CD4+CD25+FoxP3+ and CD4+IL17A+ T-cell axis in patients with breast cancer.

    PubMed

    Horlock, C; Stott, B; Dyson, P J; Morishita, M; Coombes, R C; Savage, P; Stebbing, J

    2009-04-01

    In addition to the direct targeting effects on HER2-positive cells, trastuzumab may have a therapeutic role modulating the activity of the cellular immune system in patients with breast cancer. To investigate this further, the balance of T-regulatory (T(reg)), Th17, natural killer (NK) and NK T (NKT) cells before, during and after trastuzumab therapy was investigated. Sequential frequencies of circulating T(reg) cells, Th17 cells, NK and NKT cells were measured in peripheral blood of breast cancer patients and normal controls throughout therapy. Individuals with breast cancer had significantly higher T(reg) frequencies of peripheral blood compared with healthy controls (9.2 or 8.6 vs 6%; P<0.05), and no significant differences in T(reg) frequencies were observed between HER2-positive and HER2-negative individuals. The number of Th17 cells was lowest in HER2-positive patients compared with both healthy controls and HER2-negative patients (0.31 vs 0.75% or 0.84%; P=0.01). There appeared to be an inverse relationship between T(reg) and Th17 frequencies in metastatic breast cancer (MBC) with T(reg) levels significantly reduced during treatment with trastuzumab (P=0.04), whereas Th17 frequencies were concomitantly increased (P=0.04). This study supports earlier data that T(reg) cells are present at higher frequencies in breast cancer patients compared with healthy individuals. For the first time, we show that HER2-positive individuals with breast carcinomas have reduced numbers of circulating Th17 cells, which appear, in turn to have an inverse relationship with T(reg) frequency in MBC. The change in balance of the T(reg) : Th17 ratio appears to characterise the cancer state, and furthermore, is disrupted by trastuzumab therapy. PMID:19277040

  6. Human Immunodeficiency Syndromes Affecting Human Natural Killer Cell Cytolytic Activity

    PubMed Central

    Ham, Hyoungjun; Billadeau, Daniel D.

    2013-01-01

    Natural killer (NK) cells are lymphocytes of the innate immune system that secrete cytokines upon activation and mediate the killing of tumor cells and virus-infected cells, especially those that escape the adaptive T cell response caused by the down regulation of MHC-I. The induction of cytotoxicity requires that NK cells contact target cells through adhesion receptors, and initiate activation signaling leading to increased adhesion and accumulation of F-actin at the NK cell cytotoxic synapse. Concurrently, lytic granules undergo minus-end directed movement and accumulate at the microtubule-organizing center through the interaction with microtubule motor proteins, followed by polarization of the lethal cargo toward the target cell. Ultimately, myosin-dependent movement of the lytic granules toward the NK cell plasma membrane through F-actin channels, along with soluble N-ethylmaleimide-sensitive factor attachment protein receptor-dependent fusion, promotes the release of the lytic granule contents into the cleft between the NK cell and target cell resulting in target cell killing. Herein, we will discuss several disease-causing mutations in primary immunodeficiency syndromes and how they impact NK cell-mediated killing by disrupting distinct steps of this tightly regulated process. PMID:24478771

  7. EFFECT OF NICKEL AND MANGANESE ON NATURAL KILLER CELL ACTIVITY

    EPA Science Inventory

    A single intramuscular injection of NiCl2 causes a suppression of natural killer (NK) cell activity, while a single injection of MnCl2 enhances NK activity. When injected together Mn preempts the suppressive effect of Ni on NK activity.

  8. Microchamber Device for Detection of Transporter Activity of Adherent Cells

    PubMed Central

    Tsugane, Mamiko; Uejima, Etsuko; Suzuki, Hiroaki

    2015-01-01

    We present a method to detect the transporter activity of intact adherent cells using a microchamber device. When adherent cells are seeded onto the poly-di-methyl siloxane substrate having microchambers with openings smaller than the size of a cell, the cells form a confluent layer that covers the microchambers, creating minute, confined spaces. As substances exported across the cell membrane accumulate, transporter activity can be detected by observing the fluorescence intensity increase in the microchamber. We tested the microchamber device with HeLa cells over-expressing MDR1, an ATP-binding cassette transporter, and succeeded in detecting the transport of fluorescence-conjugated paclitaxel, the anti-cancer drug, at the single-cell level. PMID:25853126

  9. Modeling Active Mechanosensing in Cell-Matrix Interactions.

    PubMed

    Chen, Bin; Ji, Baohua; Gao, Huajian

    2015-01-01

    Cells actively sense the mechanical properties of the extracellular matrix, such as its rigidity, morphology, and deformation. The cell-matrix interaction influences a range of cellular processes, including cell adhesion, migration, and differentiation, among others. This article aims to review some of the recent progress that has been made in modeling mechanosensing in cell-matrix interactions at different length scales. The issues discussed include specific interactions between proteins, the structure and mechanosensitivity of focal adhesions, the cluster effects of the specific binding, the structure and behavior of stress fibers, cells' sensing of substrate stiffness, and cell reorientation on cyclically stretched substrates. The review concludes by looking toward future opportunities in the field and at the challenges to understanding active cell-matrix interactions. PMID:26098510

  10. Peptide mini-scaffold facilitates JNK3 activation in cells

    PubMed Central

    Zhan, Xuanzhi; Stoy, Henriette; Kaoud, Tamer S.; Perry, Nicole A.; Chen, Qiuyan; Perez, Alejandro; Els-Heindl, Sylvia; Slagis, Jack V.; Iverson, Tina M.; Beck-Sickinger, Annette G.; Gurevich, Eugenia V.; Dalby, Kevin N.; Gurevich, Vsevolod V.

    2016-01-01

    Three-kinase mitogen-activated protein kinase (MAPK) signaling cascades are present in virtually all eukaryotic cells. MAPK cascades are organized by scaffold proteins, which assemble cognate kinases into productive signaling complexes. Arrestin-3 facilitates JNK activation in cells, and a short 25-residue arrestin-3 peptide was identified as the critical JNK3-binding element. Here we demonstrate that this peptide also binds MKK4, MKK7, and ASK1, which are upstream JNK3-activating kinases. This peptide is sufficient to enhance JNK3 activity in cells. A homologous arrestin-2 peptide, which differs only in four positions, binds MKK4, but not MKK7 or JNK3, and is ineffective in cells at enhancing activation of JNK3. The arrestin-3 peptide is the smallest MAPK scaffold known. This peptide or its mimics can regulate MAPKs, affecting cellular decisions to live or die. PMID:26868142

  11. Twin Knudsen Cell Configuration for Activity Measurements by Mass Spectrometry

    NASA Technical Reports Server (NTRS)

    Jacobson, N. S.

    1996-01-01

    A twin Knudsen cell apparatus for alloy activity measurements by mass spectrometry is described. Two Knudsen cells - one containing an alloy and one containing a pure component - are mounted on a single flange and translated into the sampling region via a motorized x-y table. Mixing of the molecular beams from the cells is minimized by a novel system of shutters. Activity measurements were taken on two well-characterized alloys to verify the operation of the system. Silver activity measurements are reported for Ag-Cu alloys and aluminum activity measurements are reported for Fe-Al alloys. The temperature dependence of activity for a 0.474 mol fraction Al-Fe alloy gives a partial molar heat of aluminum. Measurements taken with the twin cell show good agreement with literature values for these alloys.

  12. Cytotoxic activity of allogeneic natural killer cells on U251 glioma cells in vitro.

    PubMed

    Guo, Meng; Wu, Tingting; Wan, Lixin

    2016-07-01

    The present study aimed to observe the cytotoxic activity of allogeneic natural killer (NK) cells on U251 glioma cells and to investigate their mechanism of action to establish an effective treatment strategy for neuroglioma. Cell survival curves, colony formation assays and karyotype analysis were performed to investigate the characteristics of U251 glioma cells. The present study demonstrated that natural killer group 2, member D (NKG2D)‑major histocompatibility complex class I‑related chain A/B (MICA/B) interactions contributed to the cytotoxic effect of NK cells on K562 and U251 cells. In antibody‑blocking assays to inhibit NKG2D ligands, the cytotoxic activity was not completely attenuated, which suggested that other signaling pathways contribute to the cytotoxic activity of NK cells on tumor cells in addition to the NKG2D‑mediated activity. The present study identified that the expression levels of NKG2D ligands on the surface of target cells influenced the strength of the NK cell immune response. Furthermore, allogeneic NK cells were observed to kill glioma cells in vitro, and this anticancer activity is associated with the rate of NKG2D expression on the surface of glioma cells. PMID:27175912

  13. Active Cellular Mechanics and Information Processing in the Living Cell

    NASA Astrophysics Data System (ADS)

    Rao, M.

    2014-07-01

    I will present our recent work on the organization of signaling molecules on the surface of living cells. Using novel experimental and theoretical approaches we have found that many cell surface receptors are organized as dynamic clusters driven by active currents and stresses generated by the cortical cytoskeleton adjoining the cell surface. We have shown that this organization is optimal for both information processing and computation. In connecting active mechanics in the cell with information processing and computation, we bring together two of the seminal works of Alan Turing.

  14. Aldehyde dehydrogenase activity promotes survival of human muscle precursor cells

    PubMed Central

    Jean, Elise; Laoudj-Chenivesse, Dalila; Notarnicola, Cécile; Rouger, Karl; Serratrice, Nicolas; Bonnieu, Anne; Gay, Stéphanie; Bacou, Francis; Duret, Cédric; Carnac, Gilles

    2011-01-01

    Abstract Aldehyde dehydrogenases (ALDH) are a family of enzymes that efficiently detoxify aldehydic products generated by reactive oxygen species and might therefore participate in cell survival. Because ALDH activity has been used to identify normal and malignant cells with stem cell properties, we asked whether human myogenic precursor cells (myoblasts) could be identified and isolated based on their levels of ALDH activity. Human muscle explant-derived cells were incubated with ALDEFLUOR, a fluorescent substrate for ALDH, and we determined by flow cytometry the level of enzyme activity. We found that ALDH activity positively correlated with the myoblast-CD56+ fraction in those cells, but, we also observed heterogeneity of ALDH activity levels within CD56-purified myoblasts. Using lentiviral mediated expression of shRNA we demonstrated that ALDH activity was associated with expression of Aldh1a1 protein. Surprisingly, ALDH activity and Aldh1a1 expression levels were very low in mouse, rat, rabbit and non-human primate myoblasts. Using different approaches, from pharmacological inhibition of ALDH activity by diethylaminobenzaldehyde, an inhibitor of class I ALDH, to cell fractionation by flow cytometry using the ALDEFLUOR assay, we characterized human myoblasts expressing low or high levels of ALDH. We correlated high ALDH activity ex vivo to resistance to hydrogen peroxide (H2O2)-induced cytotoxic effect and in vivo to improved cell viability when human myoblasts were transplanted into host muscle of immune deficient scid mice. Therefore detection of ALDH activity, as a purification strategy, could allow non-toxic and efficient isolation of a fraction of human myoblasts resistant to cytotoxic damage. PMID:19840193

  15. Enzyme Activities in Polarized Cell Membranes

    PubMed Central

    Bass, L.; McIlroy, D. K.

    1968-01-01

    The theoretical pH dependence of enzyme activities in membranes of low dielectric constant is estimated. It is shown that in biological membranes some types of enzymes may attain a limiting pH sensitivity such that an increment of only 0.2 pH unit (sufficient to induce action potentials in squid axons) causes a relative activity change of over 25%. The transients of enzyme activity generated by membrane depolarization and by pH increments in the bathing solution are discussed in relation to the transients of nervous excitation. PMID:5641405

  16. Activated microglia cause reversible apoptosis of pheochromocytoma cells, inducing their cell death by phagocytosis

    PubMed Central

    Hornik, Tamara C.; Vilalta, Anna; Brown, Guy C.

    2016-01-01

    ABSTRACT Some apoptotic processes, such as phosphatidylserine exposure, are potentially reversible and do not necessarily lead to cell death. However, phosphatidylserine exposure can induce phagocytosis of a cell, resulting in cell death by phagocytosis: phagoptosis. Phagoptosis of neurons by microglia might contribute to neuropathology, whereas phagoptosis of tumour cells by macrophages might limit cancer. Here, we examined the mechanisms by which BV-2 microglia killed co-cultured pheochromocytoma (PC12) cells that were either undifferentiated or differentiated into neuronal cells. We found that microglia activated by lipopolysaccharide rapidly phagocytosed PC12 cells. Activated microglia caused reversible phosphati