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Sample records for induce dendritic cell

  1. Inducible expression of endomorphins in murine dendritic cells.

    Science.gov (United States)

    Yang, Xiaohuai; Xia, Hui; Chen, Yong; Liu, Xiaofen; Zhou, Cheng; Gao, Qin; Li, Zhenghong

    2012-12-15

    Bone marrow precursor cells were extracted from C57BL/6J mice aged 7-8 weeks, and dendritic cells were purified using anti-CD11c (a specific marker for dendritic cells) antibody-coated magnetic beads. Immunofluorescence staining revealed that the expression levels of endomorphin-1 and endomorphin-2 were upregulated in dendritic cells activated by lipopolysaccharide. An enzyme immunoassay showed that lipopolysaccharide and other Toll-like receptor ligands promoted the secretion of endomorphin-1 and endomorphin-2 from activated dendritic cells. [(3)H]-thymidine incorporation demonstrated that endomorphin-1 and endomorphin-2 both inhibited the proliferation of T lymphocyte induced by activated dendritic cells. Furthermore, this immunosuppressive effect was blocked by CTOP, a specific antagonist of µ-opioid receptors. Our experimental findings indicate that activated dendritic cells can induce the expression and secretion of endomorphins, and that endomorphins suppress T lymphocyte proliferation through activation of µ-opioid receptors.

  2. Inducible expression of endomorphins in murine dendritic cells

    Institute of Scientific and Technical Information of China (English)

    Xiaohuai Yang; Hui Xia; Yong Chen; Xiaofen Liu; Cheng Zhou; Qin Gao; Zhenghong Li

    2012-01-01

    Bone marrow precursor cells were extracted from C57BL/6J mice aged 7–8 weeks, and dendritic cells were purified using anti-CD11c (a specific marker for dendritic cells) antibody-coated magnetic beads. Immunofluorescence staining revealed that the expression levels of endomorphin-1 and endomorphin-2 were upregulated in dendritic cells activated by lipopolysaccharide. An enzyme immunoassay showed that lipopolysaccharide and other Toll-like receptor ligands promoted the secretion of endomorphin-1 and endomorphin-2 from activated dendritic cells. [3H]-thymidine incorporation demonstrated that endomorphin-1 and endomorphin-2 both inhibited the proliferation of T lymphocyte induced by activated dendritic cells. Furthermore, this immunosuppressive effect was blocked by CTOP, a specific antagonist of μ-opioid receptors. Our experimental findings indicate that activated dendritic cells can induce the expression and secretion of endomorphins, and that endomorphins suppress T lymphocyte proliferation through activation of μ-opioid receptors.

  3. Dendritic Cell

    OpenAIRE

    Sevda Söker

    2005-01-01

    Dendritic cells, a member of family of antigen presenting cells, are most effective cells in the primary immune response. Dendritic cells originated from dendron, in mean of tree in the Greek, because of their long and elaborate cytoplasmic branching processes. Dendritic cells constitute approximately 0.1 to 1 percent of the blood’s mononuclear cell. Dendritic cells are widely distributed, and specialized for antigen capture and T cell stimulation. In this article, structures and functions of...

  4. [Inflammatory dendritic cells].

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    Segura, Elodie; Amigorena, Sebastian

    2014-01-01

    Dendritic cells are a rare and heterogeneous population of professional antigen-presenting cells. Several murine dendritic cell subpopulations have been identified that differ in their phenotype and functional properties. In the steady state, committed dendritic cell precursors differentiate into lymphoid organ-resident dendritic cells and migratory tissue dendritic cells. During inflammation appears an additional dendritic cell subpopulation that has been termed « inflammatory dendritic cells ». Inflammatory dendritic cells differentiate in situ from monocytes recruited to the site of inflammation. Here, we discuss how mouse inflammatory dendritic cells differ from macrophages and from other dendritic cell populations. Finally, we review recent work on human inflammatory dendritic cells.

  5. Antithymocyte Globulin Induces a Tolerogenic Phenotype in Human Dendritic Cells.

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    Roider, Tobias; Katzfuß, Michael; Matos, Carina; Singer, Katrin; Renner, Kathrin; Oefner, Peter J; Dettmer-Wilde, Katja; Herr, Wolfgang; Holler, Ernst; Kreutz, Marina; Peter, Katrin

    2016-12-11

    Antithymocyte globulin (ATG) is used in the prevention of graft-versus-host disease during allogeneic hematopoietic stem cell transplantation. It is generally accepted that ATG mediates its immunosuppressive effect primarily via depletion of T cells. Here, we analyzed the impact of ATG-Fresenius (now Grafalon(®)) on human monocyte-derived dendritic cells (DC). ATG induced a semi-mature phenotype in DC with significantly reduced expression of CD14, increased expression of HLA-DR, and intermediate expression of CD54, CD80, CD83, and CD86. ATG-DC showed an increase in IL-10 secretion but no IL-12 production. In line with this tolerogenic phenotype, ATG caused a significant induction of indoleamine 2,3-dioxygenase expression and a concomitant increase in levels of tryptophan metabolites in the supernatants of DC. Further, ATG-DC did not induce the proliferation of allogeneic T cells in a mixed lymphocyte reaction but actively suppressed the T cell proliferation induced by mature DC. These data suggest that besides its well-known effect on T cells, ATG modulates the phenotype of DC in a tolerogenic way, which might constitute an essential part of its immunosuppressive action in vivo.

  6. Antithymocyte Globulin Induces a Tolerogenic Phenotype in Human Dendritic Cells

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    Tobias Roider

    2016-12-01

    Full Text Available Antithymocyte globulin (ATG is used in the prevention of graft-versus-host disease during allogeneic hematopoietic stem cell transplantation. It is generally accepted that ATG mediates its immunosuppressive effect primarily via depletion of T cells. Here, we analyzed the impact of ATG-Fresenius (now Grafalon® on human monocyte-derived dendritic cells (DC. ATG induced a semi-mature phenotype in DC with significantly reduced expression of CD14, increased expression of HLA-DR, and intermediate expression of CD54, CD80, CD83, and CD86. ATG-DC showed an increase in IL-10 secretion but no IL-12 production. In line with this tolerogenic phenotype, ATG caused a significant induction of indoleamine 2,3-dioxygenase expression and a concomitant increase in levels of tryptophan metabolites in the supernatants of DC. Further, ATG-DC did not induce the proliferation of allogeneic T cells in a mixed lymphocyte reaction but actively suppressed the T cell proliferation induced by mature DC. These data suggest that besides its well-known effect on T cells, ATG modulates the phenotype of DC in a tolerogenic way, which might constitute an essential part of its immunosuppressive action in vivo.

  7. Heat Shock Protein 96 Induces Maturation of Dendritic Cells

    Institute of Scientific and Technical Information of China (English)

    Chunxia Cao; Wei Yang; Yonglie Chu; Qingguang Liu; Liang Yu; Cheng'en Pan

    2006-01-01

    Objective: Heat shock protein (HSP) has the promiscuous abilities to chaperone and present a broad repertoire of tumor antigens to antigen presenting cells including DCs. In this report, we analyzed the modulation of immature DC by HSP 96 (gp96).Method: Murine bone marrow-derived DC was induced by GM-CSF plus IL-4, which aped the immunostimulatory effects of DC.Cocultured DC and gp96-peptide complexes (gp96-PC) or inactivated H22 cells, the expression of MHC class Ⅱ, CD40, CD80 was quantified by flow cytometry. The concentration of IL-12 and TNF- in culture supernatants were determined by ELISA.[51] Cr release assay was used to test specific cytotoxic T cell. Results: Our study demonstrated that the extent of DC maturation induced by gp96-PC, which was reflected in surface density of costimulatory and MHC Ⅱ molecules, was correlated with the secretion of IL-12 and with the T cellactivating potential in vitro. Conclusion: Heat shock protein 96 could be isolated and purified from H22 cells and could induce maturation of dendritic cell. Our findings might be relevance to the use of DC vaccine in therapy of human tumors.

  8. Inducing Maturation of Monocyte-Derived Dendritic Cells on Human Epithelial Cell Feeder Layer

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    Delirezh N

    2012-02-01

    Full Text Available Background: Nowadays, dendritic cells (DCs have a special place in cancer treatment strategies and they have been used for tumor immunotherapy as they can induce immune response against tumor cells. Researchers have been trying to generate efficient dendritic cells in vitro; therefore, this research was done to generate them for use in research and tumor immunotherapy. Methods: This study took place at Urmia University in 2010-2011 years. In this study plastic adherent monocytes were incubated with granulocyte-macrophage colony stimulating factor (GM-CSF and interleukin-4 (IL-4 for five days. Finally, fully matured and stable DCs were generated by 48 hours of incubation in a monocyte conditioned medium (MCM containing tumor necrosis factor-α (TNF-α and epithelial cells. Phenotypic and functional analysis were carried out by using anti-CD14, anti-CD80, anti-CD86, and anti-CD83 monoclonal antibodies, and by determining their phagocytic activity, mixed lymphocyte reaction (MLR and cytokine production, respectively. Results: Dendritic cells were produced with high levels of surface molecule, i.e. of CD80, CD83, CD86, HLA-DR, expression and low levels of CD14 expression. Dendritic cells showed efficient phagocytosis and ability to stimulate T-lymphocytes. Moreover, dendritic cells could secrete high levels of interleukin-12 (IL-12 cytokine which was depictive of their full maturation. Measurement of the produced cytokines showed the generation of type-1 dendritic cells (DC1. Conclusion: Our study showed that skin epithelial cells could induce maturation of monocyte-derived dendritic cells (DCs. This feeder layer led to the production of efficient dendritic cells with the ability to be used for tumor immunotherapy.

  9. Immunity and Tolerance Induced by Intestinal Mucosal Dendritic Cells

    OpenAIRE

    Julio Aliberti

    2016-01-01

    Dendritic cells present in the digestive tract are constantly exposed to environmental antigens, commensal flora, and invading pathogens. Under steady-state conditions, these cells have high tolerogenic potential, triggering differentiation of regulatory T cells to protect the host from unwanted proinflammatory immune responses to innocuous antigens or commensals. On the other hand, these cells must discriminate between commensal flora and invading pathogens and mount powerful immune response...

  10. Monocyte cell surface glycosaminoglycans positively modulate IL-4-induced differentiation toward dendritic cells.

    NARCIS (Netherlands)

    Dekker, E. den; Grefte, S.; Huijs, T.; Dam, G.B. ten; Versteeg, E.M.M.; Berk, L.C.J. van den; Bladergroen, B.A.; Kuppevelt, A.H.M.S.M. van; Figdor, C.G.; Torensma, R.

    2008-01-01

    IL-4 induces the differentiation of monocytes toward dendritic cells (DCs). The activity of many cytokines is modulated by glycosaminoglycans (GAGs). In this study, we explored the effect of GAGs on the IL-4-induced differentiation of monocytes toward DCs. IL-4 dose-dependently up-regulated the expr

  11. An Engineered Herpesvirus Activates Dendritic Cells and Induces Protective Immunity

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    Ma, Yijie; Chen, Min; Jin, Huali; Prabhakar, Bellur S.; Valyi-Nagy, Tibor; He, Bin

    2017-01-01

    Herpes simplex viruses (HSV) are human pathogens that switch between lytic and latent infection. While attenuated HSV is explored for vaccine, the underlying event remains poorly defined. Here we report that recombinant HSV-1 with a mutation in the γ134.5 protein, a virulence factor, stimulates dendritic cell (DC) maturation which is dependent on TANK-binding kinase 1 (TBK1). When exposed to CD11+ DCs, the mutant virus that lacks the amino terminus of γ134.5 undergoes temporal replication without production of infectious virus. Mechanistically, this leads to sequential phosphorylation of interferon regulatory factor 3 (IRF3) and p65/RelA. In correlation, DCs up-regulate the expression of co-stimulatory molecules and cytokines. However, selective inhibition of TBK1 precludes phosphorylation of IRF3 and subsequent DC activation by the γ134.5 mutant. Herein, the γ134.5 mutant is immune-stimulatory and non-destructive to DCs. Remarkably, upon immunization the γ134.5 mutant induces protection against lethal challenge by the wild type virus, indicative of its vaccine potential. Furthermore, CD11+ DCs primed by the γ134.5 mutant in vivo mediate protection upon adoptive transfer. These results suggest that activation of TBK1 by engineered HSV is crucial for DC maturation, which may contribute to protective immunity. PMID:28150813

  12. Ebola virus infection induces irregular dendritic cell gene expression.

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    Melanson, Vanessa R; Kalina, Warren V; Williams, Priscilla

    2015-02-01

    Filoviruses subvert the human immune system in part by infecting and replicating in dendritic cells (DCs). Using gene arrays, a phenotypic profile of filovirus infection in human monocyte-derived DCs was assessed. Monocytes from human donors were cultured in GM-CSF and IL-4 and were infected with Ebola virus Kikwit variant for up to 48 h. Extracted DC RNA was analyzed on SuperArray's Dendritic and Antigen Presenting Cell Oligo GEArray and compared to uninfected controls. Infected DCs exhibited increased expression of cytokine, chemokine, antiviral, and anti-apoptotic genes not seen in uninfected controls. Significant increases of intracellular antiviral and MHC I and II genes were also noted in EBOV-infected DCs. However, infected DCs failed to show any significant difference in co-stimulatory T-cell gene expression from uninfected DCs. Moreover, several chemokine genes were activated, but there was sparse expression of chemokine receptors that enabled activated DCs to home to lymph nodes. Overall, statistically significant expression of several intracellular antiviral genes was noted, which may limit viral load but fails to stop replication. EBOV gene expression profiling is of vital importance in understanding pathogenesis and devising novel therapeutic treatments such as small-molecule inhibitors.

  13. Generation of dendritic cells and macrophages from human induced pluripotent stem cells aiming at cell therapy.

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    Senju, S; Haruta, M; Matsumura, K; Matsunaga, Y; Fukushima, S; Ikeda, T; Takamatsu, K; Irie, A; Nishimura, Y

    2011-09-01

    This report describes generation of dendritic cells (DCs) and macrophages from human induced pluripotent stem (iPS) cells. iPS cell-derived DC (iPS-DC) exhibited the morphology of typical DC and function of T-cell stimulation and antigen presentation. iPS-DC loaded with cytomegalovirus (CMV) peptide induced vigorous expansion of CMV-specific autologous CD8+ T cells. Macrophages (iPS-MP) with activity of zymosan phagocytosis and C5a-induced chemotaxis were also generated from iPS cells. Genetically modified iPS-MPs were generated by the introduction of expression vectors into undifferentiated iPS cells, isolation of transfectant iPS cell clone and subsequent differentiation. By this procedure, we generated iPS-MP expressing a membrane-bound form of single chain antibody (scFv) specific to amyloid β (Aβ), the causal protein of Alzheimer's disease. The scFv-transfectant iPS-MP exhibited efficient Aβ-specific phagocytosis activity. iPS-MP expressing CD20-specific scFv engulfed and killed BALL-1 B-cell leukemia cells. Anti-BALL-1 effect of iPS-MP in vivo was demonstrated in a xeno-transplantation model using severe combined immunodeficient mice. In addition, we established a xeno-free culture protocol to generate iPS-DC and iPS-MP. Collectively, we demonstrated the possibility of application of iPS-DC and macrophages to cell therapy.

  14. Dendritic cells fused with different pancreatic carcinoma cells induce different T-cell responses

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    Andoh Y

    2013-01-01

    Full Text Available Yoshiaki Andoh,1,2 Naohiko Makino,2 Mitsunori Yamakawa11Department of Pathological Diagnostics, 2Department of Gastroenterology, Yamagata University School of Medicine, Yamagata, JapanBackground: It is unclear whether there are any differences in the induction of cytotoxic T lymphocytes (CTL and CD4+CD25high regulatory T-cells (Tregs among dendritic cells (DCs fused with different pancreatic carcinomas. The aim of this study was to compare the ability to induce cytotoxicity by human DCs fused with different human pancreatic carcinoma cell lines and to elucidate the causes of variable cytotoxicity among cell lines.Methods: Monocyte-derived DCs, which were generated from peripheral blood mononuclear cells (PBMCs, were fused with carcinoma cells such as Panc-1, KP-1NL, QGP-1, and KP-3L. The induction of CTL and Tregs, and cytokine profile of PBMCs stimulated by fused DCs were evaluated.Results: The cytotoxicity against tumor targets induced by PBMCs cocultured with DCs fused with QGP-1 (DC/QGP-1 was very low, even though PBMCs cocultured with DCs fused with other cell lines induced significant cytotoxicity against the respective tumor target. The factors causing this low cytotoxicity were subsequently investigated. DC/QGP-1 induced a significant expansion of Tregs in cocultured PBMCs compared with DC/KP-3L. The level of interleukin-10 secreted in the supernatants of PBMCs cocultured with DC/QGP-1 was increased significantly compared with that in DC/KP-3L. Downregulation of major histocompatibility complex class I expression and increased secretion of vascular endothelial growth factor were observed with QGP-1, as well as in the other cell lines.Conclusion: The present study demonstrated that the cytotoxicity induced by DCs fused with pancreatic cancer cell lines was different between each cell line, and that the reduced cytotoxicity of DC/QGP-1 might be related to the increased secretion of interleukin-10 and the extensive induction of Tregs

  15. Chicken dendritic cells are susceptible to highly pathogenic avian influenza viruses which induce strong cytokine responses

    NARCIS (Netherlands)

    Vervelde, L.; Reemens, S.S.; Haarlem, van D.A.; Post, J.; Claassen, E.A.W.; Rebel, J.M.J.; Jansen, C.A.

    2013-01-01

    Infection with highly pathogenic avian influenza (HPAI) in birds and mammals is associated with severe pathology and increased mortality. We hypothesize that in contrast to low pathogenicity avian influenza (LPAI) infection, HPAI infection of chicken dendritic cells (DC) induces a cytokine deregulat

  16. Dendritic cells overexpressing Fas-ligand induce pulmonary vasculitis in mice

    NARCIS (Netherlands)

    Buonocore, S; Flamand, [No Value; Claessen, N; Heeringa, P; Goldman, M; Florquin, S

    2004-01-01

    Dendritic cells (DC) genetically engineered to express Fas (CD95) ligand (FasL-DC) have been proposed as immunotherapeutic tools to induce tolerance to allografts. However, we and others recently showed that FasL-DC elicit a vigorous inflammatory response involving granulocytes and can promote Th1-t

  17. Dendritic cells enhance UHMWPE wear particle-induced osteoclast differentiation of macrophages.

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    Cang, Dingwei; Guo, Kaijin; Zhao, Fengchao

    2015-10-01

    Ultra-high molecular weight polyethylene (UHMWPE) has been widely used in large joint replacement. Osteolysis induced by the UHMWPE wear particles is one of the main causes of replacement failure. This study aims to elucidate whether dendritic cells play a role in UHMWPE particle-induced osteolysis. An in vitro Raw 264.7 and DC 2.4 coculture system was employed to examine the effects of dendritic cells on the inflammatory and osteoclastogenic responses of Raw 264.7 toward UHMWPE particles. The expression of cytokines, NF-κB, and osteoclast marker genes was analyzed by ELISA, western blot, or quantitative PCR. The osteoclast differentiation was measured by TRAP staining and flow cytometry. UHMWPE particles induced Raw 264.7 cells to differentiate into osteoclasts, which was enhanced by coculturing with DC 2.4 cells. DC 2.4 cells augmented UHMWPE particle-elicited activation of NF-κB signaling, higher levels of TNF-α and MCP-1, and an increased expression of MMP-9, Calcr, and Ctsk, though DC 2.4 coculture alone did not significantly cause the aforementioned changes. These results suggest that dendritic cells, among other immune cells recruited by UHMWPE particle induced inflammation, could further exacerbate inflammation and osteolysis.

  18. Downregulation of the Syk Signaling Pathway in Intestinal Dendritic Cells Is Sufficient To Induce Dendritic Cells That Inhibit Colitis.

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    Hang, Long; Blum, Arthur M; Kumar, Sangeeta; Urban, Joseph F; Mitreva, Makedonka; Geary, Timothy G; Jardim, Armando; Stevenson, Mary M; Lowell, Clifford A; Weinstock, Joel V

    2016-10-01

    Helminthic infections modulate host immunity and may protect people in less-developed countries from developing immunological diseases. In a murine colitis model, the helminth Heligmosomoides polygyrus bakeri prevents colitis via induction of regulatory dendritic cells (DCs). The mechanism driving the development of these regulatory DCs is unexplored. There is decreased expression of the intracellular signaling pathway spleen tyrosine kinase (Syk) in intestinal DCs from H. polygyrus bakeri-infected mice. To explore the importance of this observation, it was shown that intestinal DCs from DC-specific Syk(-/-) mice were powerful inhibitors of murine colitis, suggesting that loss of Syk was sufficient to convert these cells into their regulatory phenotype. DCs sense gut flora and damaged epithelium via expression of C-type lectin receptors, many of which signal through the Syk signaling pathway. It was observed that gut DCs express mRNA encoding for C-type lectin (CLEC) 7A, CLEC9A, CLEC12A, and CLEC4N. H. polygyrus bakeri infection downmodulated CLEC mRNA expression in these cells. Focusing on CLEC7A, which encodes for the dectin-1 receptor, flow analysis showed that H. polygyrus bakeri decreases dectin-1 expression on the intestinal DC subsets that drive Th1/Th17 development. DCs become unresponsive to the dectin-1 agonist curdlan and fail to phosphorylate Syk after agonist stimulation. Soluble worm products can block CLEC7A and Syk mRNA expression in gut DCs from uninfected mice after a brief in vitro exposure. Thus, downmodulation of Syk expression and phosphorylation in intestinal DCs could be important mechanisms through which helminths induce regulatory DCs that limit colitis.

  19. Anti-atherogenic peptide Ep1.B derived from apolipoprotein E induces tolerogenic plasmacytoid dendritic cells.

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    Bellemore, S M; Nikoopour, E; Au, B C Y; Krougly, O; Lee-Chan, E; Haeryfar, S M; Singh, B

    2014-09-01

    Tolerogenic dendritic cells (DCs) play a critical role in the induction of regulatory T cells (Tregs ), which in turn suppress effector T cell responses. We have previously shown the induction of DCs from human and mouse monocytic cell lines, mouse splenocytes and human peripheral blood monocytes by a novel apolipoprotein E (ApoE)-derived self-peptide termed Ep1.B. We also showed that this C-terminal region 239-252 peptide of ApoE has strong anti-atherogenic activity and reduces neointimal hyperplasia after vascular surgery in rats and wild-type as well as ApoE-deficient mice. In this study, we explored the phenotype of DC subset induced by Ep1.B from monocytic cell lines and from the bone marrow-derived cells. We found Ep1.B treatment induced cells that showed characteristics of plasmacytoid dendritic cells (pDC). We explored in-vitro and in-vivo effects of Ep1.B-induced DCs on antigen-specific T cell responses. Upon in-vivo injection of these cells with antigen, the subsequent ex-vivo antigen-specific proliferation of lymph node cells and splenocytes from recipient mice was greatly reduced. Our results suggest that Ep1.B-induced pDCs promote the generation of Treg cells, and these cells contribute to the induction of peripheral tolerance in adaptive immunity and potentially contribute its anti-atherogenic activity.

  20. In vitro antitumor immune response induced by fusion of dendritic cells and colon cancer cells

    Institute of Scientific and Technical Information of China (English)

    Feng Xu; Ying-Jiang Ye; Shan Wang

    2004-01-01

    AIM: The prevention of recurrence of colon cancer (CC)after operation is very important for improvement of the prognosis of CC patients, especially those with micrometastasis. The generation of fused cells between dendritic cells (DCs) and tumor cells maybe an effective approach for tumor antigen presentation in immunotherapy. In this study,we fused human colon caner SW480 cells and human peripheral blood - derived DCs to induce an antitumor activity against human CC.METHODS: CC SW480 cells and human peripheral blood derived DCs were fused with 500 mL/L polyethylene glycol (PEG).RESULTS: The specific T cell responses activated by fusion cells (FCs), were observed. About 100 mL/L to 160 mL/L of the PEG-treated non-adherent cells with fluorescences were considered to be dendritomas that highly expressed the key molecules for antigen presentation in our five cases. In vitro studies showed that fusions effectively activated CD8+ T lymphocytes to secrete interferon-γ. The early apoptotic ratio of the colon cancer SW480 cells was higher than that of controls, which was affected by cytotoxic T lymphocytes (CTLs) stimulated by dendritomas.CONCLUSION: The data indicate that fusion of tumor cells with DCs is an attractive strategy to induce tumor rejection.

  1. Aire-Overexpressing Dendritic Cells Induce Peripheral CD4+ T Cell Tolerance

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    Dongbei Li

    2015-12-01

    Full Text Available Autoimmune regulator (Aire can promote the ectopic expression of peripheral tissue-restricted antigens (TRAs in thymic medullary epithelial cells (mTECs, which leads to the deletion of autoreactive T cells and consequently prevents autoimmune diseases. However, the functions of Aire in the periphery, such as in dendritic cells (DCs, remain unclear. This study’s aim was to investigate the effect of Aire-overexpressing DCs (Aire cells on the functions of CD4+ T cells and the treatment of type 1 diabetes (T1D. We demonstrated that Aire cells upregulated the mRNA levels of the tolerance-related molecules CD73, Lag3, and FR4 and the apoptosis of CD4+ T cells in STZ-T1D mouse-derived splenocytes. Furthermore, following insulin stimulation, Aire cells decreased the number of CD4+ IFN-γ+ T cells in both STZ-T1D and WT mouse-derived splenocytes and reduced the expression levels of TCR signaling molecules (Ca2+ and p-ERK in CD4+ T cells. We observed that Aire cells-induced CD4+ T cells could delay the development of T1D. In summary, Aire-expressing DCs inhibited TCR signaling pathways and decreased the quantity of CD4+IFN-γ+ autoreactive T cells. These data suggest a mechanism for Aire in the maintenance of peripheral immune tolerance and provide a potential method to control autoimmunity by targeting Aire.

  2. Aire-Overexpressing Dendritic Cells Induce Peripheral CD4+ T Cell Tolerance

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    Li, Dongbei; Li, Haijun; Fu, Haiying; Niu, Kunwei; Guo, Yantong; Guo, Chuan; Sun, Jitong; Li, Yi; Yang, Wei

    2015-01-01

    Autoimmune regulator (Aire) can promote the ectopic expression of peripheral tissue-restricted antigens (TRAs) in thymic medullary epithelial cells (mTECs), which leads to the deletion of autoreactive T cells and consequently prevents autoimmune diseases. However, the functions of Aire in the periphery, such as in dendritic cells (DCs), remain unclear. This study’s aim was to investigate the effect of Aire-overexpressing DCs (Aire cells) on the functions of CD4+ T cells and the treatment of type 1 diabetes (T1D). We demonstrated that Aire cells upregulated the mRNA levels of the tolerance-related molecules CD73, Lag3, and FR4 and the apoptosis of CD4+ T cells in STZ-T1D mouse-derived splenocytes. Furthermore, following insulin stimulation, Aire cells decreased the number of CD4+ IFN-γ+ T cells in both STZ-T1D and WT mouse-derived splenocytes and reduced the expression levels of TCR signaling molecules (Ca2+ and p-ERK) in CD4+ T cells. We observed that Aire cells-induced CD4+ T cells could delay the development of T1D. In summary, Aire-expressing DCs inhibited TCR signaling pathways and decreased the quantity of CD4+IFN-γ+ autoreactive T cells. These data suggest a mechanism for Aire in the maintenance of peripheral immune tolerance and provide a potential method to control autoimmunity by targeting Aire. PMID:26729097

  3. Serum amyloid A inhibits dendritic cell apoptosis to induce glucocorticoid resistance in CD4(+) T cells.

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    Ather, J L; Fortner, K A; Budd, R C; Anathy, V; Poynter, M E

    2013-09-05

    Mediators produced by the airway epithelium control the activation, recruitment, and survival of pulmonary dendritic cells (DC) that present antigen to CD4(+) T cells during the genesis and exacerbation of allergic asthma. The epithelial-derived acute phase protein, serum amyloid A (SAA), induces DC maturation and TH17 polarization. TH17 responses are associated with severe forms of allergic asthma that are poorly controlled by corticosteroids. We sought to determine whether SAA would enhance the survival of DC during serum starvation and could then contribute to the development of a glucocorticoid-resistant phenotype in CD4(+) T cells. Bone marrow-derived dendritic cells (BMDC) that were serum starved in the presence of SAA were protected from activation of caspase-3 and released less lactate dehydrogenase. In comparison with untreated serum-starved BMDC, treatment with SAA downregulated mRNA expression of the pro-apoptotic molecule Bim, increased production of the pro-survival heat shock protein 70 (HSP70), and induced secretion of pro-inflammatory cytokines. SAA-treated BMDC that were serum starved for 48 h remained capable of presenting antigen and induced OTII CD4(+) T cells to secrete IL-17A, IL-17F, IL-21, IL-22, and IFNγ in the presence of ovalbumin. IL-17A, IL-17F, IL-21, and IFNγ production occurred even when the CD4(+) T cells were treated with dexamethasone (Dex), whereas glucocorticoid treatment abolished cytokine secretion by T cells cocultured with untreated serum-starved BMDC. Measurement of Dex-responsive gene expression demonstrated CD4(+) T cells as the target of glucocorticoid hyperresponsiveness manifest as a consequence of BMDC stimulation by SAA. Finally, allergic airway disease induced by SAA and antigen inhalation was unresponsive to Dex treatment. Our results indicate that apo-SAA affects DC to both prolong their viability and increase their inflammatory potential under apoptosis-inducing conditions. These findings reveal mechanisms

  4. Variation of Neisseria gonorrhoeae lipooligosaccharide directs dendritic cell-induced T helper responses.

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    Sandra J van Vliet

    2009-10-01

    Full Text Available Gonorrhea is one of the most prevalent sexually transmitted diseases in the world. A naturally occurring variation of the terminal carbohydrates on the lipooligosaccharide (LOS molecule correlates with altered disease states. Here, we investigated the interaction of different stable gonoccocal LOS phenotypes with human dendritic cells and demonstrate that each variant targets a different set of receptors on the dendritic cell, including the C-type lectins MGL and DC-SIGN. Neisseria gonorrhoeae LOS phenotype C constitutes the first bacterial ligand to be described for the human C-type lectin receptor MGL. Both MGL and DC-SIGN are locally expressed at the male and female genital area, the primary site of N. gonorrhoeae infection. We show that targeting of different C-type lectins with the N. gonorrhoeae LOS variants results in alterations in dendritic cell cytokine secretion profiles and the induction of distinct adaptive CD4(+ T helper responses. Whereas N. gonorrhoeae variant A with a terminal N-acetylglucosamine on its LOS was recognized by DC-SIGN and induced significantly more IL-10 production, phenotype C, carrying a terminal N-acetylgalactosamine, primarily interacted with MGL and skewed immunity towards the T helper 2 lineage. Together, our results indicate that N. gonorrhoeae LOS variation allows for selective manipulation of dendritic cell function, thereby shifting subsequent immune responses in favor of bacterial survival.

  5. Neural Cell Adhesion Molecule NrCAM Regulates Semaphorin 3F-Induced Dendritic Spine Remodeling

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    Demyanenko, Galina P.; Mohan, Vishwa; Zhang, Xuying; Brennaman, Leann H.; Dharbal, Katherine E.S.; Tran, Tracy S.; Manis, Paul B.

    2014-01-01

    Neuron-glial related cell adhesion molecule (NrCAM) is a regulator of axon growth and repellent guidance, and has been implicated in autism spectrum disorders. Here a novel postsynaptic role for NrCAM in Semaphorin3F (Sema3F)-induced dendritic spine remodeling was identified in pyramidal neurons of the primary visual cortex (V1). NrCAM localized to dendritic spines of star pyramidal cells in postnatal V1, where it was coexpressed with Sema3F. NrCAM deletion in mice resulted in elevated spine densities on apical dendrites of star pyramidal cells at both postnatal and adult stages, and electron microscopy revealed increased numbers of asymmetric synapses in layer 4 of V1. Whole-cell recordings in cortical slices from NrCAM-null mice revealed increased frequency of mEPSCs in star pyramidal neurons. Recombinant Sema3F-Fc protein induced spine retraction on apical dendrites of wild-type, but not NrCAM-null cortical neurons in culture, while re-expression of NrCAM rescued the spine retraction response. NrCAM formed a complex in brain with Sema3F receptor subunits Neuropilin-2 (Npn-2) and PlexinA3 (PlexA3) through an Npn-2-binding sequence (TARNER) in the extracellular Ig1 domain. A trans heterozygous genetic interaction test demonstrated that Sema3F and NrCAM pathways interacted in vivo to regulate spine density in star pyramidal neurons. These findings reveal NrCAM as a novel postnatal regulator of dendritic spine density in cortical pyramidal neurons, and an integral component of the Sema3F receptor complex. The results implicate NrCAM as a contributor to excitatory/inhibitory balance in neocortical circuits. PMID:25143608

  6. Retinoic acid primes human dendritic cells to induce gut-homing, IL-10-producing regulatory T cells

    NARCIS (Netherlands)

    Bakdash, G.; Vogelpoel, L.T.; Capel, T.M. van; Kapsenberg, M.L.; Jong, E.C. de

    2015-01-01

    The vitamin A metabolite all-trans retinoic acid (RA) is an important determinant of intestinal immunity. RA primes dendritic cells (DCs) to express CD103 and produce RA themselves, which induces the gut-homing receptors alpha4beta7 and CCR9 on T cells and amplifies transforming growth factor (TGF)-

  7. FoxP3+ regulatory T cells essentially contribute to peripheral CD8+ T-cell tolerance induced by steady-state dendritic cells

    Science.gov (United States)

    Schildknecht, Anita; Brauer, Sabine; Brenner, Corinne; Lahl, Katharina; Schild, Hansjörg; Sparwasser, Tim; Probst, Hans Christian; van den Broek, Maries

    2010-01-01

    Peripheral T-cell tolerance is thought to significantly contribute to the prevention of autoimmunity, and it has been shown that antigen-presenting steady-state dendritic cells efficiently induce peripheral tolerance. We previously showed that dendritic-cell–induced tolerance is a T-cell–intrinsic process that depends on coinhibitory molecules such as programmed death-1. Here we specifically analyze the involvement of FoxP3+ regulatory T cells, which are known to be important for maintenance of self-tolerance. We show that antigen presentation by steady-state dendritic cells failed to induce peripheral tolerance in the absence of FoxP3+ regulatory T cells but induced protective CD8+ T-cell–mediated immunity instead. Regulatory T-cell–depleted mice had massively increased numbers of dendritic cells in lymph nodes. Dendritic cells isolated from mice without regulatory T cells had up-regulated costimulatory molecules and showed stronger T-cell stimulatory capacity ex vivo, suggesting that regulatory T cells contribute to peripheral tolerance by keeping the dendritic cells in an immature state. Using blocking antibodies, we demonstrate that CTLA-4 but not IL-10 is necessary for control of dendritic cells by regulatory T cells. PMID:20018763

  8. CD69 modulates sphingosine-1-phosphate-induced migration of skin dendritic cells

    OpenAIRE

    Lamana, Amalia; Martin, Pilar; de la Fuente, Hortensia; Martinez-Muñoz, Laura; Cruz-Adalia, Aranzazu; Ramirez-Huesca, Marta; Escribano, Cristina; Gollmer, Kathrin; Mellado, Mario; Stein, Jens V.; Rodriguez-Fernandez, Jose Luis; Sanchez-Madrid, Francisco; del Hoyo, Gloria Martinez

    2011-01-01

    In this study, we have investigated the role of CD69, an early inducible leukocyte activation receptor, in murine dendritic cell (DC) differentiation, maturation, and migration. Skin DCs and DC subsets present in mouse lymphoid organs express CD69 in response to maturation stimuli. Using a contact sensitization model, we show that skin DCs migrated more efficiently to draining lymph nodes (LNs) in the absence of CD69. This was confirmed by subcutaneous transfer of CD69–/– DCs, which presented...

  9. Mycobacterium tuberculosis infection induces non-apoptotic cell death of human dendritic cells

    LENUS (Irish Health Repository)

    Ryan, Ruth CM

    2011-10-24

    Abstract Background Dendritic cells (DCs) connect innate and adaptive immunity, and are necessary for an efficient CD4+ and CD8+ T cell response after infection with Mycobacterium tuberculosis (Mtb). We previously described the macrophage cell death response to Mtb infection. To investigate the effect of Mtb infection on human DC viability, we infected these phagocytes with different strains of Mtb and assessed viability, as well as DNA fragmentation and caspase activity. In parallel studies, we assessed the impact of infection on DC maturation, cytokine production and bacillary survival. Results Infection of DCs with live Mtb (H37Ra or H37Rv) led to cell death. This cell death proceeded in a caspase-independent manner, and without nuclear fragmentation. In fact, substrate assays demonstrated that Mtb H37Ra-induced cell death progressed without the activation of the executioner caspases, 3\\/7. Although the death pathway was triggered after infection, the DCs successfully underwent maturation and produced a host-protective cytokine profile. Finally, dying infected DCs were permissive for Mtb H37Ra growth. Conclusions Human DCs undergo cell death after infection with live Mtb, in a manner that does not involve executioner caspases, and results in no mycobactericidal effect. Nonetheless, the DC maturation and cytokine profile observed suggests that the infected cells can still contribute to TB immunity.

  10. Bifidobacterium bifidum Actively Changes the Gene Expression Profile Induced by Lactobacillus acidophilus in Murine Dendritic Cells

    DEFF Research Database (Denmark)

    Weiss, Gudrun Margarethe; Rasmussen, Simon; Fink, Lisbeth Nielsen;

    2010-01-01

    Dendritic cells (DC) play a pivotal regulatory role in activation of both the innate as well as the adaptive immune system by responding to environmental microorganisms. We have previously shown that Lactobacillus acidophilus induces a strong production of the pro-inflammatory and Th1 polarizing...... cytokine IL-12 in DC, whereas bifidobacteria do not induce IL-12 but inhibit the IL-12 production induced by lactobacilli. In the present study, genome-wide microarrays were used to investigate the gene expression pattern of murine DC stimulated with Lactobacillus acidophilus NCFM and Bifidobacterium...

  11. Cell death induced by the application of alternating magnetic fields to nanoparticle-loaded dendritic cells

    Energy Technology Data Exchange (ETDEWEB)

    Marcos-Campos, I; AsIn, L; Torres, T E; Tres, A; Ibarra, M R; Goya, G F [Instituto de Nanociencia de Aragon (INA), Mariano Esquillor s/n, CP 50018, Zaragoza (Spain); Marquina, C, E-mail: goya@unizar.es [Condensed Matter Department, Sciences Faculty, University of Zaragoza, 50009 (Spain)

    2011-05-20

    In this work, the capability of primary, monocyte-derived dendritic cells (DCs) to uptake iron oxide magnetic nanoparticles (MNPs) is assessed and a strategy to induce selective cell death in these MNP-loaded DCs using external alternating magnetic fields (AMFs) is reported. No significant decrease in the cell viability of MNP-loaded DCs, compared to the control samples, was observed after five days of culture. The number of MNPs incorporated into the cytoplasm was measured by magnetometry, which confirmed that 1-5 pg of the particles were uploaded per cell. The intracellular distribution of these MNPs, assessed by transmission electron microscopy, was found to be primarily inside the endosomic structures. These cells were then subjected to an AMF for 30 min and the viability of the blank DCs (i.e. without MNPs), which were used as control samples, remained essentially unaffected. However, a remarkable decrease of viability from approximately 90% to 2-5% of DCs previously loaded with MNPs was observed after the same 30 min exposure to an AMF. The same results were obtained using MNPs having either positive (NH{sub 2}{sup +}) or negative (COOH{sup -}) surface functional groups. In spite of the massive cell death induced by application of AMF to MNP-loaded DCs, the number of incorporated magnetic particles did not raise the temperature of the cell culture. Clear morphological changes at the cell structure after magnetic field application were observed using scanning electron microscopy. Therefore, local damage produced by the MNPs could be the main mechanism for the selective cell death of MNP-loaded DCs under an AMF. Based on the ability of these cells to evade the reticuloendothelial system, these complexes combined with an AMF should be considered as a potentially powerful tool for tumour therapy.

  12. Cell death induced by the application of alternating magnetic fields to nanoparticle-loaded dendritic cells

    Science.gov (United States)

    Marcos-Campos, I.; Asín, L.; Torres, T. E.; Marquina, C.; Tres, A.; Ibarra, M. R.; Goya, G. F.

    2011-05-01

    In this work, the capability of primary, monocyte-derived dendritic cells (DCs) to uptake iron oxide magnetic nanoparticles (MNPs) is assessed and a strategy to induce selective cell death in these MNP-loaded DCs using external alternating magnetic fields (AMFs) is reported. No significant decrease in the cell viability of MNP-loaded DCs, compared to the control samples, was observed after five days of culture. The number of MNPs incorporated into the cytoplasm was measured by magnetometry, which confirmed that 1-5 pg of the particles were uploaded per cell. The intracellular distribution of these MNPs, assessed by transmission electron microscopy, was found to be primarily inside the endosomic structures. These cells were then subjected to an AMF for 30 min and the viability of the blank DCs (i.e. without MNPs), which were used as control samples, remained essentially unaffected. However, a remarkable decrease of viability from approximately 90% to 2-5% of DCs previously loaded with MNPs was observed after the same 30 min exposure to an AMF. The same results were obtained using MNPs having either positive (NH2 + ) or negative (COOH - ) surface functional groups. In spite of the massive cell death induced by application of AMF to MNP-loaded DCs, the number of incorporated magnetic particles did not raise the temperature of the cell culture. Clear morphological changes at the cell structure after magnetic field application were observed using scanning electron microscopy. Therefore, local damage produced by the MNPs could be the main mechanism for the selective cell death of MNP-loaded DCs under an AMF. Based on the ability of these cells to evade the reticuloendothelial system, these complexes combined with an AMF should be considered as a potentially powerful tool for tumour therapy.

  13. T cells induce extended class II MHC compartments in dendritic cells in a Toll-like receptor-dependent manner.

    Science.gov (United States)

    Boes, Marianne; Bertho, Nicolas; Cerny, Jan; Op den Brouw, Marjolein; Kirchhausen, Tomas; Ploegh, Hidde

    2003-10-15

    Interaction of Ag-loaded dendritic cells with Ag-specific CD4 T cells induces the formation of long tubular class II MHC-positive compartments that polarize toward the T cell. We show involvement of a Toll-like receptor-mediated signal in this unusual form of intracellular class II MHC trafficking. First, wild-type dendritic cells loaded with LPS-free Ag failed to show formation of class II-positive tubules upon Ag-specific T cell engagement, but did so upon supplementation of the Ag with low concentrations of LPS. Second, Ag-loaded myeloid differentiation factor 88 -deficient dendritic cells failed to form these tubules upon interaction with T cells, regardless of the presence of LPS. Finally, inclusion of a cell-permeable peptide that blocks TNFR-associated factor 6 function, downstream of myeloid differentiation factor 88, blocked T cell-dependent tubulation. A Toll-like receptor-dependent signal is thus required to allow Ag-loaded dendritic cells to respond to T cell contact by formation of extended endosomal compartments. This activation does not result in massive translocation of class II MHC molecules to the cell surface.

  14. Vaccination with dendritic cells pulsed with hepatitis C pseudo particles induces specific immune responses in mice

    Institute of Scientific and Technical Information of China (English)

    Kilian Weigand; Franziska Voigt; Jens Encke; Birgit Hoyler; Wolfgang Stremmel; Christoph Eisenbach

    2012-01-01

    AIM:To explore dendritic cells (DCs) multiple functions in immune modulation.METHODS:We used bone-marrow derived dendritic cells from BALB/c mice pulsed with pseudo particles from the hepatitis C virus to vaccinate naive BALB/c mice.Hepatitis C virus (HCV) pseudo particles consist of the genotype 1b derived envelope proteins E1 and E2,covering a non-HCV core structure.Thus,not a single epitope,but the whole "viral surface" induces immunogenicity.For vaccination,mature and activated DC were injected subcutaneously twice.RESULTS:Humoral and cellular immune responses measured by enzyme-linked immunosorbent assay and interferon-gamma enzyme-linked immunosorbent spot test showed antibody production as well as T-cells directed against HCV.Furthermore,T-cell responses confirmed two highly immunogenic regions in E1 and E2 outside the hypervariable region 1.CONCLUSION:Our results indicate dendritic cells as a promising vaccination model for HCV infection that should be evaluated further.

  15. Aire-Overexpressing Dendritic Cells Induce Peripheral CD4⁺ T Cell Tolerance.

    Science.gov (United States)

    Li, Dongbei; Li, Haijun; Fu, Haiying; Niu, Kunwei; Guo, Yantong; Guo, Chuan; Sun, Jitong; Li, Yi; Yang, Wei

    2015-12-29

    Autoimmune regulator (Aire) can promote the ectopic expression of peripheral tissue-restricted antigens (TRAs) in thymic medullary epithelial cells (mTECs), which leads to the deletion of autoreactive T cells and consequently prevents autoimmune diseases. However, the functions of Aire in the periphery, such as in dendritic cells (DCs), remain unclear. This study's aim was to investigate the effect of Aire-overexpressing DCs (Aire cells) on the functions of CD4⁺ T cells and the treatment of type 1 diabetes (T1D). We demonstrated that Aire cells upregulated the mRNA levels of the tolerance-related molecules CD73, Lag3, and FR4 and the apoptosis of CD4⁺ T cells in STZ-T1D mouse-derived splenocytes. Furthermore, following insulin stimulation, Aire cells decreased the number of CD4⁺ IFN-γ⁺ T cells in both STZ-T1D and WT mouse-derived splenocytes and reduced the expression levels of TCR signaling molecules (Ca(2+) and p-ERK) in CD4⁺ T cells. We observed that Aire cells-induced CD4⁺ T cells could delay the development of T1D. In summary, Aire-expressing DCs inhibited TCR signaling pathways and decreased the quantity of CD4⁺IFN-γ⁺ autoreactive T cells. These data suggest a mechanism for Aire in the maintenance of peripheral immune tolerance and provide a potential method to control autoimmunity by targeting Aire.

  16. Tolerogenic IDO+ dendritic cells are induced by PD-1-expressing mast cells

    Directory of Open Access Journals (Sweden)

    Cecilia Pessoa Rodrigues

    2016-01-01

    Full Text Available Mast cells (MC are tissue resident cells, rich in inflammatory mediators, involved in allergic reactions, and with an increasingly recognized role in immunomodulation. Dendritic cells (DCs, on the other hand, are central to the determination of immune response patterns, being highly efficient antigen-presenting cells that respond promptly to changes in their microenvironment. Here, we show that direct cell contact between immature monocyte-derived DCs (iDCs and MC bends DCs towards tolerance induction. DCs that had direct contact with MC (MC-iDC decreased HLA-DR but increased PD-L1 expression and stimulated regulatory T lymphocytes, which expresses FoxP3+, secrete TGF-β and IL-10, and suppress the proliferation of mitogen-stimulated naïve T lymphocytes. Furthermore, MC-iDC expressed higher levels of indoleamine-2,3-deoxigenase (IDO, a phenomenon that was blocked by treatment of MC with anti-PD-1 or by the treatment of DCs with anti-PD-L1 or anti-PD-L2, but not by blocking of H1 and H2 histamine receptors on DCs. Contact with MC also increased phosphorylated STAT-3 levels in iDCs. When a STAT-3 inhibitor, JSI-124, was added to the DCs before contact with MC, the MC-iDC recovered their ability to induce allogeneic T cell proliferation and did not increase their IDO expression.

  17. Dysfunction of Murine Dendritic Cells Induced by Incubation with Tumor Cells

    Institute of Scientific and Technical Information of China (English)

    Fengguang Gao; Xin Hui; Xianghuo He; Dafang Wan; Jianren Gu

    2008-01-01

    In vivo studies showed that dendritic cell (DC) dysfunction occurred in tumor microcnvironment. As tumors were composed of many kinds of cells, the direct effects of tumor cells on immature DCs (imDCs) are needed for further studies in vitro. In the present study, bone marrow-derived imDCs were incubated with lymphoma, hepatoma and menaloma cells in vitro and surface molecules in imDCs were determined by flow cytometry. Then, imDCs incubated with tumor cells or control imDCs were further pulsed with tumor lysates and then incubated with splenocytes to perform mixed lymphocyte reaction. The DC-dependent tumor antigen-specific T cell proliferation,and IL-12 secretion were determined by flow cytometry, and enzyme-linked immunosorbent assay respectively.Finally, the DC-dependent tumor-associated antigen-specific CTL was determined by enzyme-linked immunospot assay. The results showed that tumor cell-DC incubation down-regulated the surface molecules in imDCs, such as CD80, CD54, CDllb, CD11a and MHC class Ⅱ molecules. The abilities of DC-dependent antigen-specific T cell proliferation and IL-12 secretion were also decreased by tumor cell incubation in vitro. Most importantly, the ability for antigenic-specific CTL priming of DCs was also decreased by incubation with tumor cells. In the present in vitro study demonstrated that the defective abilities of DCs induced by tumor cell co-incubation and the co-incubation system might be useful for future study of tumor-immune cells direct interaction and for drug screen of immune-modulation.

  18. Plasmacytoid dendritic cells promote HIV-1-induced group 3 innate lymphoid cell depletion.

    Science.gov (United States)

    Zhang, Zheng; Cheng, Liang; Zhao, Juanjuan; Li, Guangming; Zhang, Liguo; Chen, Weiwei; Nie, Weiming; Reszka-Blanco, Natalia J; Wang, Fu-Sheng; Su, Lishan

    2015-09-01

    Group 3 innate lymphoid cells (ILC3s) have demonstrated roles in promoting antibacterial immunity, maintaining epithelial barrier function, and supporting tissue repair. ILC3 alterations are associated with chronic inflammation and inflammatory disease; however, the characteristics and relevant regulatory mechanisms of this cell population in HIV-1 infection are poorly understood due in part to a lack of a robust model. Here, we determined that functional human ILC3s develop in lymphoid organs of humanized mice and that persistent HIV-1 infection in this model depletes ILC3s, as observed in chronic HIV-1-infected patients. In HIV-1-infected mice, effective antiretroviral therapy reversed the loss of ILC3s. HIV-1-dependent reduction of ILC3s required plasmacytoid dendritic cells (pDCs), IFN-I, and the CD95/FasL pathway, as targeted depletion or blockade of these prevented HIV-1-induced ILC3 depletion in vivo and in vitro, respectively. Finally, we determined that HIV-1 infection induces CD95 expression on ILC3s via a pDC- and IFN-I-dependent mechanism that sensitizes ILC3s to undergo CD95/FasL-mediated apoptosis. We conclude that chronic HIV-1 infection depletes ILC3s through pDC activation, induction of IFN-I, and CD95-mediated apoptosis.

  19. Adipose Tissue Dendritic Cells Are Independent Contributors to Obesity-Induced Inflammation and Insulin Resistance.

    Science.gov (United States)

    Cho, Kae Won; Zamarron, Brian F; Muir, Lindsey A; Singer, Kanakadurga; Porsche, Cara E; DelProposto, Jennifer B; Geletka, Lynn; Meyer, Kevin A; O'Rourke, Robert W; Lumeng, Carey N

    2016-11-01

    Dynamic changes of adipose tissue leukocytes, including adipose tissue macrophage (ATM) and adipose tissue dendritic cells (ATDCs), contribute to obesity-induced inflammation and metabolic disease. However, clear discrimination between ATDC and ATM in adipose tissue has limited progress in the field of immunometabolism. In this study, we use CD64 to distinguish ATM and ATDC, and investigated the temporal and functional changes in these myeloid populations during obesity. Flow cytometry and immunostaining demonstrated that the definition of ATM as F4/80(+)CD11b(+) cells overlaps with other leukocytes and that CD45(+)CD64(+) is specific for ATM. The expression of core dendritic cell genes was enriched in CD11c(+)CD64(-) cells (ATDC), whereas core macrophage genes were enriched in CD45(+)CD64(+) cells (ATM). CD11c(+)CD64(-) ATDCs expressed MHC class II and costimulatory receptors, and had similar capacity to stimulate CD4(+) T cell proliferation as ATMs. ATDCs were predominantly CD11b(+) conventional dendritic cells and made up the bulk of CD11c(+) cells in adipose tissue with moderate high-fat diet exposure. Mixed chimeric experiments with Ccr2(-/-) mice demonstrated that high-fat diet-induced ATM accumulation from monocytes was dependent on CCR2, whereas ATDC accumulation was less CCR2 dependent. ATDC accumulation during obesity was attenuated in Ccr7(-/-) mice and was associated with decreased adipose tissue inflammation and insulin resistance. CD45(+)CD64(+) ATM and CD45(+)CD64(-)CD11c(+) ATDCs were identified in human obese adipose tissue and ATDCs were increased in s.c. adipose tissue compared with omental adipose tissue. These results support a revised strategy for unambiguous delineation of ATM and ATDC, and suggest that ATDCs are independent contributors to adipose tissue inflammation during obesity. Copyright © 2016 by The American Association of Immunologists, Inc.

  20. Th and Treg response induced by Aspergillus fumigatus pulsed dendritic cells in vitro

    Institute of Scientific and Technical Information of China (English)

    Wang Runchao; Wan Zhe; Li Ruoyu

    2014-01-01

    Background Dendritic cells (DCs) can recognize the pathogen-associated molecular patterns (PAMP) of Aspergillus fumigatus (A.fumigatus),activating the immune response.During A.fumigatus infection,a Th and Treg response induced in the fungi-pulsed DCs is not yet well understood.Methods In this study,bone marrow-derived dendritic cells (BMDCs) were separated and proliferated from C57BL/6 mice.A.fumigatus pulsed DCs were generated and cultured with CD4+ T cells derived from the spleen of C57BL/6 mice in vitro.CD4+ T cells differentiation after co-culture were analyzed by flow cytometry,ELISA,and real-time PCR analysis.Results The A.fumigatus pulsed DCs exhibited increased Th1 and Treg frequency,Th1-related cytokines (IFN-γ and IL-12),Treg-related cytokines (TGF-β) and T-bet,and Foxp3 mRNA levels compared with the control group.There was no significant difference between A.fumigatus pulsed DCs group and the control group about Th17 and Th2 frequency.Conclusions The inactivated conidia of A.fumigatus were able to activate BMDCs and made them capable of triggering T cell responses in vitro.A.fumigatus loaded DCs was a weak inducer of Th17 and Th2,but induced a strong Th1 and Treg response.

  1. Effect of insulin on functional status of cord blood-derived dendritic cells and on dendritic cell-induced CTL cytotoxicity against pancreatic cancer cell lines

    Institute of Scientific and Technical Information of China (English)

    Qiu-Liang Liu; Yi-Sheng Wang; Jia-Xiang Wang

    2009-01-01

    BACKGROUND: Dendritic cells (DCs) are the most important antigen-presenting cells in the human body, and DCs with different mature status possess different or even opposite functions. This study was designed to explore the influence of insulin on the functional status of cord blood-derived DCs and on DC-induced cytotoxic T lymphocyte (CTL) activity against pancreatic cancer cell lines. METHODS: Mononuclear cells were isolated from fresh cord blood. Interleukin-4 (IL-4) and granulocyte-macrophage colony-stimulating factor (GM-CSF) were used to induce or stimulate the mononuclear cells. Insulin at different concentrations served to modify DCs, and then DC morphology, number, and growth status were assessed. The DC immunophenotype was detected with a flow cytometer. The IL-12 in DC supernatant was determined by ELISA. DC functional status was evaluated by the autologous mixed lymphocyte reaction. T lymphocytes were induced by insulin-modified DCs to become CTLs. The CTL cytotoxicity against pancreatic cancer cell lines was determined. RESULTS:  Mononuclear cells from cord blood can be differentiated into DCs by cytokine induction and insulin modification. With the increase in insulin concentration (2.5-25 mg/L), the expression of DC HLA-DR, CD1α, CD80, and CD83 was significantly increased, the DC ability to secrete IL-12 was significantly improved, DC function to activate autologous lymphocytes was significantly enhanced, and the cytotoxicity of CTLs induced by insulin-modified DCs against pancreatic cancer cell lines was significantly strengthened. CONCLUSIONS: Insulin may facilitate DC induction and maturation, and improve the reproductive activity of autologous lymphocytes. The cytotoxicity of CTLs induced by insulin-modified DCs against pancreatic cancer cell lines was significantly enhanced. Insulin may serve as a factor modifying DCs and inducing CTLs in vitro in insulin biotherapy.

  2. Integrin CD11b positively regulates TLR4-induced signalling pathways in dendritic cells but not in macrophages

    Science.gov (United States)

    Ling, Guang Sheng; Bennett, Jason; Woollard, Kevin J.; Szajna, Marta; Fossati-Jimack, Liliane; Taylor, Philip R.; Scott, Diane; Franzoso, Guido; Cook, H. Terence; Botto, Marina

    2014-01-01

    Tuned and distinct responses of macrophages and dendritic cells to Toll-like receptor 4 (TLR4) activation induced by lipopolysaccharide (LPS) underpin the balance between innate and adaptive immunity. However, the molecule(s) that confer these cell-type-specific LPS-induced effects remain poorly understood. Here we report that the integrin αM (CD11b) positively regulates LPS-induced signalling pathways selectively in myeloid dendritic cells but not in macrophages. In dendritic cells, which express lower levels of CD14 and TLR4 than macrophages, CD11b promotes MyD88-dependent and MyD88-independent signalling pathways. In particular, in dendritic cells CD11b facilitates LPS-induced TLR4 endocytosis and is required for the subsequent signalling in the endosomes. Consistent with this, CD11b deficiency dampens dendritic cell-mediated TLR4-triggered responses in vivo leading to impaired T-cell activation. Thus, by modulating the trafficking and signalling functions of TLR4 in a cell-type-specific manner CD11b fine tunes the balance between adaptive and innate immune responses initiated by LPS.

  3. Cytotoxic activity of interferon alpha induced dendritic cells as a biomarker of glioblastoma

    Science.gov (United States)

    Mishinov, S. V.; Stupak, V. V.; Tyrinova, T. V.; Leplina, O. Yu.; Ostanin, A. A.; Chernykh, E. R.

    2016-08-01

    Dendritic cells (DCs) are the most potent antigen presenting cells that can play direct role in anti-tumor immune response as killer cells. DC tumoricidal activity can be stimulated greatly by type I IFN (IFNα and IFNβ). In the present study, we examined cytostatic and cytotoxic activity of monocyte-derived IFNα-induced DCs generated from patients with brain glioma and evaluated the potential use of these parameters in diagnostics of high-grade gliomas. Herein, we demonstrated that patient DCs do not possess the ability to inhibit the growth of tumor HEp-2 cell line but low-grade and high-grade glioma patients do not differ significantly in DC cytostatic activity. However, glioma patient DCs are characterized by reduced cytotoxic activity against HEp-2 cells. The impairment of DC cytotoxic function is observed mainly in glioblastoma patients. The cytotoxic activity of DCs against HEp-2 cells below 9% is an informative marker for glioblastomas.

  4. Antitumour activities of cytokine-induced killer cells and dendritic cells in vitro and in vivo

    Institute of Scientific and Technical Information of China (English)

    ZHANG Song; JIANG Shu-juan; ZHANG Cai-qing; WANG Hong-mei; BAI Chun-xue

    2005-01-01

    @@ Solid tumour cells show a resistance to immunological effector cells in vitro.1 The resistance may be one reason why these tumours withstand immunotherapeutic approaches in humans.Dendritic cells (DC) play an important role in the immune response to tumour associated antigens in humans.DC in the periphery capture and process antigens,express lymphocyte costimulatory molecules,migrate to lymphoid organs and secrete cytokines to initiate immune response.

  5. Cryptococcus gattii is killed by dendritic cells, but evades adaptive immunity by failing to induce dendritic cell maturation.

    Science.gov (United States)

    Huston, Shaunna M; Li, Shu Shun; Stack, Danuta; Timm-McCann, Martina; Jones, Gareth J; Islam, Anowara; Berenger, Byron M; Xiang, Richard F; Colarusso, Pina; Mody, Christopher H

    2013-07-01

    During adaptive immunity to pathogens, dendritic cells (DCs) capture, kill, process, and present microbial Ags to T cells. Ag presentation is accompanied by DC maturation driven by appropriate costimulatory signals. However, current understanding of the intricate regulation of these processes remains limited. Cryptococcus gattii, an emerging fungal pathogen in the Pacific Northwest of Canada and the United States, fails to stimulate an effective immune response in otherwise healthy hosts leading to morbidity or death. Because immunity to fungal pathogens requires intact cell-mediated immunity initiated by DCs, we asked whether C. gattii causes dysregulation of DC functions. C. gattii was efficiently bound and internalized by human monocyte-derived DCs, trafficked to late phagolysosomes, and killed. Yet, even with this degree of DC activation, the organism evaded pathways leading to DC maturation. Despite the ability to recognize and kill C. gattii, immature DCs failed to mature; there was no increased expression of MHC class II, CD86, CD83, CD80, and CCR7, or decrease of CD11c and CD32, which resulted in suboptimal T cell responses. Remarkably, no increase in TNF-α was observed in the presence of C. gattii. However, addition of recombinant TNF-α or stimulation that led to TNF-α production restored DC maturation and restored T cell responses. Thus, despite early killing, C. gattii evades DC maturation, providing a potential explanation for its ability to infect immunocompetent individuals. We have also established that DCs retain the ability to recognize and kill C. gattii without triggering TNF-α, suggesting independent or divergent activation pathways among essential DC functions.

  6. Chloroquine modulates HIV-1-induced plasmacytoid dendritic cell alpha interferon: implication for T-cell activation.

    Science.gov (United States)

    Martinson, Jeffrey A; Montoya, Carlos J; Usuga, Xiomara; Ronquillo, Rollie; Landay, Alan L; Desai, Seema N

    2010-02-01

    Plasmacytoid dendritic cells (pDC) contribute to antiviral immunity mainly through recognition of microbial products and viruses via intracellular Toll-like receptor 7 (TLR7) or TLR9, resulting in the production of type I interferons (IFNs). Although interferons reduce the viral burden in the acute phase of infection, their role in the chronic phase is unclear. The presence of elevated plasma IFN-alpha levels in advanced HIV disease and its association with microbial translocation in chronic HIV infection lead us to hypothesize that IFN-alpha could contribute to immune activation. Blocking of IFN-alpha production using chloroquine, an endosomal inhibitor, was tested in a novel in vitro model system with the aim of characterizing the effects of chloroquine on HIV-1-mediated TLR signaling, IFN-alpha production, and T-cell activation. Our results indicate that chloroquine blocks TLR-mediated activation of pDC and MyD88 signaling, as shown by decreases in the levels of the downstream signaling molecules IRAK-4 and IRF-7 and by inhibition of IFN-alpha synthesis. Chloroquine decreased CD8 T-cell activation induced by aldrithiol-2-treated HIV-1 in peripheral blood mononuclear cell cultures. In addition to blocking pDC activation, chloroquine also blocked negative modulators of the T-cell response, such as indoleamine 2,3-dioxygenase (IDO) and programmed death ligand 1 (PDL-1). Our results indicate that TLR stimulation and production of IFN-alpha by pDC contribute to immune activation and that blocking of these pathways using chloroquine may interfere with events contributing to HIV pathogenesis. Our results suggests that a safe, well-tolerated drug such as chloroquine can be proposed as an adjuvant therapeutic candidate along with highly active antiretroviral therapy to control immune activation in HIV-1 infection.

  7. Chloroquine Modulates HIV-1-Induced Plasmacytoid Dendritic Cell Alpha Interferon: Implication for T-Cell Activation▿

    Science.gov (United States)

    Martinson, Jeffrey A.; Montoya, Carlos J.; Usuga, Xiomara; Ronquillo, Rollie; Landay, Alan L.; Desai, Seema N.

    2010-01-01

    Plasmacytoid dendritic cells (pDC) contribute to antiviral immunity mainly through recognition of microbial products and viruses via intracellular Toll-like receptor 7 (TLR7) or TLR9, resulting in the production of type I interferons (IFNs). Although interferons reduce the viral burden in the acute phase of infection, their role in the chronic phase is unclear. The presence of elevated plasma IFN-α levels in advanced HIV disease and its association with microbial translocation in chronic HIV infection lead us to hypothesize that IFN-α could contribute to immune activation. Blocking of IFN-α production using chloroquine, an endosomal inhibitor, was tested in a novel in vitro model system with the aim of characterizing the effects of chloroquine on HIV-1-mediated TLR signaling, IFN-α production, and T-cell activation. Our results indicate that chloroquine blocks TLR-mediated activation of pDC and MyD88 signaling, as shown by decreases in the levels of the downstream signaling molecules IRAK-4 and IRF-7 and by inhibition of IFN-α synthesis. Chloroquine decreased CD8 T-cell activation induced by aldrithiol-2-treated HIV-1 in peripheral blood mononuclear cell cultures. In addition to blocking pDC activation, chloroquine also blocked negative modulators of the T-cell response, such as indoleamine 2,3-dioxygenase (IDO) and programmed death ligand 1 (PDL-1). Our results indicate that TLR stimulation and production of IFN-α by pDC contribute to immune activation and that blocking of these pathways using chloroquine may interfere with events contributing to HIV pathogenesis. Our results suggests that a safe, well-tolerated drug such as chloroquine can be proposed as an adjuvant therapeutic candidate along with highly active antiretroviral therapy to control immune activation in HIV-1 infection. PMID:19949061

  8. GENETICALLY MODIFIED DENDRITIC CELLS INDUCED SPECIFIC CYTOTOXITY AGAINST HUMAN HCC CELLS IN VITRO

    Institute of Scientific and Technical Information of China (English)

    刘彬彬; 叶胜龙; 贺平; 郑宁; 赵燕; 孙瑞霞; 刘银坤; 汤钊猷

    2004-01-01

    Objective: to transduce the tumor associated antigen gene MAGE-1 and/or IL-12 gene into dendritic cells (DC) and to observe the in vitro cytotoxic effect induced by the genetically modified DC against the human hepatocellular carcinoma (HCC) cell line SMMC7721. Methods: the MAGE-1 gene was inserted into the retrovirus vector LXSN to construct the recombinant retrovirus LMSN. The monocyte-derived DCs were transfected at appropriate differentiation stage by LMSN and/or a recombinant adenovirus AdmiL-12, which containing murine IL-12 gene. The control groups included retrovirus LXSN transfected, adenovirus AdBGFP transfected and non-transfected DCs. The MAGE-1 gene expression was identified by western blot and the mIL-12 p70 secretion was detected by ELISA assay. The in vitro cytotoxicities against SMMC7721 induced by genetically modified and control groups of DC were tested by MTT assay. Results: The MAGE-1 expression was detected by a monoclonal antibody in DCs tranfected with LMSN but not in control groups. At 16 h, 24 h and 48 h after transfection with AdmIL-12, the concentration of the mIL-12 p70 in the culture medium was 580pg/106 cells, 960pg/106 cells and 1100pg/106 cells respectively. The mIL-12 p70 secretions were not detected in other groups. The lytic activity (as judged by % lysis) induced by each groups of DC was 94.2(5.2% (LMSN and AdmIL-12 cotransfected group), 78.9(3.6% (LMSN transfected groups), 52.6(9.7% (AdmIL-12 transfected group), 34.7(4.3% (LXSN transfected group), 36.3(3.8% (AdBGFP transfected group) and 3.9(2.0% (non-transfected group) respectively. Except for LXSN transfected and AdBGFP transfected group, the difference of the lytic activities between other groups were statistically significant (P<0.05). Conclusion: The MAGE-1 gene modified DCs can induce relatively specific cytotoxicty against SMMC7721 in vitro and thus suggested that those genetically engineered DCs have the potential to serve as novel vaccine for HCC. Transduction of

  9. Tumor cell lysate-pulsed dendritic cells induce a T cell response against colon cancer in vitro and in vivo.

    Science.gov (United States)

    Wu, Yu-gang; Wu, Guang-zhou; Wang, Liang; Zhang, Yan-Yun; Li, Zhong; Li, De-Chun

    2010-09-01

    To investigate whether tumor cell lysate-pulsed (TP) dendritic cells (DCs) induce cytotoxic T lymphocyte (CTL) activity against colon cancer in vitro and in vivo. Hematopoietic progenitor cells were magnetically isolated from BALB/c mice bone marrow cells. These cells were cultured with cytokines GM-CSF, IL-4, and TNFalpha to induce their maturation. They were analyzed by morphological observation and phenotype analysis. DCs were pulsed with tumor cell lysate obtained by rapid freezing and thawing at a 1:3 DC:tumor cell ratio. CTL activity and interferon gamma (IFNgamma) secretion was evaluated ex vivo. In order to determine whether or not vaccination with CT26 TP DCs induce the therapeutic potential in the established colon tumor model, CT26 colon tumor cells were implanted subcutaneously (s.c.) in the midflank of naïve BALB/c mice. Tumor-bearing mice were injected with vaccination with CT26 TP DCs on days 3 and 10. Tumor growth was assessed every 2-3 days. Finally, CTL activity and IFNgamma secretion were evaluated in immunized mice. Hematopoietic progenitor cells from mice bone marrow cells cultured with cytokines for 8 days showed the character of typical mature DCs. Morphologically, these cells were large with oval or irregularly shaped nuclei and with many small dendrites. Phenotypically, FACS analysis showed that they expressed high levels of MHC II, CD11b, CD80, and CD86 antigen, and were negative for CD8alpha. However, immature DCs cultured with cytokines for 5 days did not have typical DCs phenotypic markers. Ex vivo primed T cells with CT26 TP DCs were able to induce effective CTL activity against CT26 tumor cells, but not B16 tumor cells (E:T = 100:1, 60.36 +/- 7.11% specific lysis in CT26 group vs. 17.36 +/- 4.10% specific lysis in B16 group), and produced higher levels of IFNgamma when stimulated with CT26 tumor cells but not when stimulated with B16 tumor cells (1210.33 +/- 72.15 pg/ml in CT26 group vs. 182.25 +/- 25.51 pg/ml in B16 group, P models

  10. Listeria monocytogenes protein fraction induces dendritic cells maturation and T helper 1 immune responses.

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    Azad Saei

    2014-02-01

    Full Text Available Fully mature dendritic cells (DCs play pivotal role in inducing immune responses and converting naïve T lymphocytes into functional Th1 cells. We aimed to evaluate Listeria Monocytogenes-derived protein fractions to induce DC maturation and stimulating T helper (Th1 immune responses.In the present study, we fractionated Listeria Monocytogenes-derived proteins by adding of ammonium sulfate in a stepwise manner. DCs were also generated from C57BL/6 mice bone marrow precursor cells. Then, the effects of protein fractions on bone marrow derived DC (BMDC maturation were evaluated. In addition, we assessed the capacity of activated DCs to induce cytokine production and proliferation of lymphocytes.Listeria-derived protein fractions induced fully mature DCs expressing high costimulatory molecules such as CD80, CD86 and CD40. DCs that were activated by selected F3 fraction had low capacity to uptake exogenous antigens while secreted high levels of Interleukine (IL-12. Moreover, lymphocytes cultured with activated BMDCs produced high amounts of IFN-γ and showed higher proliferation than control. Listeria derived protein fractions differently influenced DC maturation.In conclusion, Listeria protein activated-BMDCs can be used as a cell based vaccine to induce anti-tumor immune responses.

  11. Vpx-containing Dendritic Cell Vaccine Vectors Induce CTLs and Reactivate Latent HIV-1 in vitro

    Science.gov (United States)

    Norton, Thomas D.; Miller, Elizabeth A.; Bhardwaj, Nina; Landau, Nathaniel R.

    2015-01-01

    Eradication of HIV-1 from an infected individual requires a means of inducing production of virus from latently infected cells and stimulating an immune response against the infected cells. We report the development of lentiviral vectors that transduce dendritic cells (DCs) to both induce production of virus from latently infected cells and stimulate antigen-specific CTLs. The vectors package Vpx, a lentiviral accessory protein that counteracts the SAMHD1-mediated block to DC transduction, allowing for long-term expression of vector-encoded proteins. The vectors encode influenza or HIV-1-derived epitopes fused via a self-cleaving peptide to CD40L that releases the peptide into the endoplasmic reticulum for entry into the antigen presentation pathway. Expression of CD40L caused transduced DCs to mature and produce Th1-skewing cytokines. The DCs presented antigen to CD8 T cells, enhancing antigen-specific CTLs. Coculture of the transduced DCs with latently infected cells induced high level virus production, an effect that was mediated by TNF-α. The ability of a DC vaccine to reactivate latent HIV-1 and stimulate an adaptive immune response provides a means to reduce the size of the latent reservoir in patients. This strategy can also be applied to develop DC vaccines for other diseases. PMID:25567537

  12. Glucocorticoid-Induced TNFR family Related gene (GITR) enhances dendritic cell activity.

    Science.gov (United States)

    Ronchetti, Simona; Nocentini, Giuseppe; Petrillo, Maria Grazia; Bianchini, Rodolfo; Sportoletti, Paolo; Bastianelli, Alessandra; Ayroldi, Emira M; Riccardi, Carlo

    2011-03-30

    Glucocorticoid-Induced TNFR family Related gene (GITR), a Tumor Necrosis Factor Receptor Superfamily (TNFRSF) member involved in immune/inflammatory processes, has been previously shown to regulate T cell activation. To study GITR role in antigen presenting cells, we evaluated the capability of bone marrow derived dendritic cells (BMDC) from GITR(-/-) mice to stimulate the activation of CD4(+)CD25(-) T lymphocytes. We found that GITR(-/-) BMDC are weaker stimulators of T cell proliferation than GITR(+/+) BMDC, either in syngenic or allogenic BMDC/T cell co-cultures. Expression of GITR in GITR(-/-) BMDC restored their ability to activate T cells while GITR silencing in GITR(+/+) BMDC inhibited the capability to stimulate T cells. GITR(-/-) BMDC showed a reduced production of the pro-inflammatory cytokine IL-6 and an increased production of the anti-inflammatory cytokine IL-10. Notably, co-culture of CD4(+)CD25(-) cells with GITR(-/-) BMDC originated FoxP3(+) cells, secreting IL-10 and TGF-β. Finally, in vivo injection of GITR(-/-) OVA-loaded BMDC led to a lower cell number and a lower activated cell number in draining lymph nodes than in GITR(+/+) OVA-loaded BMDC injected mice. Together, these results indicate that GITR plays a role in regulating BMDC activity.

  13. SMAC Mimetic BV6 Induces Cell Death in Monocytes and Maturation of Monocyte-Derived Dendritic Cells

    Science.gov (United States)

    Holtz, Philipp; Kapp, Markus; Grigoleit, Götz Ulrich; Schmuck, Carsten; Wajant, Harald; Siegmund, Daniela

    2011-01-01

    Background Compounds mimicking the inhibitory effect of SMAC / DIABLO on X-linked inhibitor of apoptosis (XIAP) have been developed with the aim to achieve sensitization for apoptosis of tumor cells resistant due to deregulated XIAP expression. It turned out that SMAC mimetics also have complex effects on the NFκB system and TNF signaling. In view of the overwhelming importance of the NFκB transcription factors in the immune system, we analyzed here the effects of the SMAC mimetic BV6 on immune cells. Principal Findings BV6 induced apoptotic and necrotic cell death in monocytes while T-cells, dendritic cells and macrophages were largely protected against BV6-induced cell death. In immature dendritic cells BV6 treatment resulted in moderate activation of the classical NFκB pathway, but it also diminished the stronger NFκB-inducing effect of TNF and CD40L. Despite its inhibitory effect on TNF- and CD40L signaling, BV6 was able to trigger maturation of immature DCs as indicated by upregulation of CD83, CD86 and IL12. Significance The demonstrated effects of SMAC mimetics on immune cells may complicate the development of tumor therapeutic concepts based on these compounds but also arise the possibility to exploit them for the development of immune stimulatory therapies. PMID:21738708

  14. SMAC mimetic BV6 induces cell death in monocytes and maturation of monocyte-derived dendritic cells.

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    Nicole Müller-Sienerth

    Full Text Available BACKGROUND: Compounds mimicking the inhibitory effect of SMAC/DIABLO on X-linked inhibitor of apoptosis (XIAP have been developed with the aim to achieve sensitization for apoptosis of tumor cells resistant due to deregulated XIAP expression. It turned out that SMAC mimetics also have complex effects on the NFκB system and TNF signaling. In view of the overwhelming importance of the NFκB transcription factors in the immune system, we analyzed here the effects of the SMAC mimetic BV6 on immune cells. PRINCIPAL FINDINGS: BV6 induced apoptotic and necrotic cell death in monocytes while T-cells, dendritic cells and macrophages were largely protected against BV6-induced cell death. In immature dendritic cells BV6 treatment resulted in moderate activation of the classical NFκB pathway, but it also diminished the stronger NFκB-inducing effect of TNF and CD40L. Despite its inhibitory effect on TNF- and CD40L signaling, BV6 was able to trigger maturation of immature DCs as indicated by upregulation of CD83, CD86 and IL12. SIGNIFICANCE: The demonstrated effects of SMAC mimetics on immune cells may complicate the development of tumor therapeutic concepts based on these compounds but also arise the possibility to exploit them for the development of immune stimulatory therapies.

  15. Native cellulose nanofibrills induce immune tolerance in vitro by acting on dendritic cells

    Science.gov (United States)

    Tomić, Sergej; Kokol, Vanja; Mihajlović, Dušan; Mirčić, Aleksandar; Čolić, Miodrag

    2016-08-01

    Cellulose nanofibrills (CNFs) are attractive biocompatible, natural nanomaterials for wide biomedical applications. However, the immunological mechanisms of CNFs have been poorly investigated. Considering that dendritic cells (DCs) are the key immune regulatory cells in response to nanomaterials, our aim was to investigate the immunological mechanisms of CNFs in a model of DC-mediated immune response. We found that non-toxic concentrations of CNFs impaired the differentiation, and subsequent maturation of human monocyte-derived (mo)-DCs. In a co-culture with CD4+T cells, CNF-treated mo-DCs possessed a weaker allostimulatory and T helper (Th)1 and Th17 polarizing capacity, but a stronger capacity to induce Th2 cells and CD4+CD25hiFoxP3hi regulatory T cells. This correlated with an increased immunoglobulin-like transcript-4 and indolamine dioxygenase-1 expression by CNF-treated mo-DCs, following the partial internalization of CNFs and the accumulation of CD209 and actin bundles at the place of contacts with CNFs. Cumulatively, we showed that CNFs are able to induce an active immune tolerance by inducing tolerogenic DCs, which could be beneficial for the application of CNFs in wound healing and chronic inflammation therapies.

  16. Mycobacterium tuberculosislpdC, Rv0462, induces dendritic cell maturation and Th1 polarization

    Energy Technology Data Exchange (ETDEWEB)

    Heo, Deok Rim [Department of Microbiology and Immunology, School of Medicine, Pusan National University, Beom-eo Ri, Mulgum Eop, Yangsan, Gyeongsangnam-do 626-770 (Korea, Republic of); Shin, Sung Jae; Kim, Woo Sik [Department of Microbiology, College of Medicine, Chungnam National University, Munwha-Dong, Jung-Ku, Daejeon 301-747 (Korea, Republic of); Noh, Kyung Tae; Park, Jin Wook; Son, Kwang Hee [Department of Microbiology and Immunology, School of Medicine, Pusan National University, Beom-eo Ri, Mulgum Eop, Yangsan, Gyeongsangnam-do 626-770 (Korea, Republic of); Park, Won Sun [Department of Physiology, Kangwon National University, School of Medicine, Chuncheon 200-701 (Korea, Republic of); Lee, Min-Goo [Department of Physiology, Korea University, College of Medicine, Anam-dong, Sungbuk-Gu, Seoul 136-705 (Korea, Republic of); Kim, Daejin [Department of Anatomy, Chung-Ang University, College of Medicine, 221 Heuksuk-Dong, Dongjak-Ku, Seoul 156-756 (Korea, Republic of); Shin, Yong Kyoo [Department of Pharmacology, Chung-Ang University, College of Medicine, 221 Heuksuk-Dong, Dongjak-Ku, Seoul 156-756 (Korea, Republic of); Jung, In Duk, E-mail: jungid@pusan.ac.kr [Department of Microbiology and Immunology, School of Medicine, Pusan National University, Beom-eo Ri, Mulgum Eop, Yangsan, Gyeongsangnam-do 626-770 (Korea, Republic of); Research Institute of Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Beom-eo Ri, Mulgum Eop, Yangsan, Gyeongsangnam-do 626-770 (Korea, Republic of); Park, Yeong-Min, E-mail: immunpym@pusan.ac.kr [Department of Microbiology and Immunology, School of Medicine, Pusan National University, Beom-eo Ri, Mulgum Eop, Yangsan, Gyeongsangnam-do 626-770 (Korea, Republic of); Research Institute of Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Beom-eo Ri, Mulgum Eop, Yangsan, Gyeongsangnam-do 626-770 (Korea, Republic of)

    2011-08-05

    Highlights: {yields} Treatment with Rv0462 induces the expression of surface molecules and the production of cytokines in DCs. {yields} Rv0462 induces the activation of MAPKs. {yields} Rv0462-treated DCs enhances the proliferation of CD4{sup +} T cells. -- Abstract: Mycobacterium tuberculosis, the etiological factor of pulmonary tuberculosis, causes significant morbidity and mortality worldwide. Activation of host immune responses for containment of mycobacterial infections involves participation of innate immune cells, such as dendritic cells (DCs). In this study, we demonstrated that the gene encoding lipoamide dehydrogenase C (lpdC) from M. tuberculosis, Rv0462, induce maturation and activation of DCs involved in the MAPKs signaling pathway. Moreover, Rv0462-treated DCs activated naive T cells, polarized CD4{sup +} and CD8{sup +} T cells to secrete IFN-{gamma} in syngeneic mixed lymphocyte reactions, which would be expected to contribute to Th1 polarization of the immune response. Our results suggest that Rv0462 can contribute to the innate and adaptive immune responses during tuberculosis infection, and thus modulate the clinical course of tuberculosis.

  17. Myeloid dendritic cells induce HIV-1 latency in non-proliferating CD4+ T cells.

    Science.gov (United States)

    Evans, Vanessa A; Kumar, Nitasha; Filali, Ali; Procopio, Francesco A; Yegorov, Oleg; Goulet, Jean-Philippe; Saleh, Suha; Haddad, Elias K; da Fonseca Pereira, Candida; Ellenberg, Paula C; Sekaly, Rafick-Pierre; Cameron, Paul U; Lewin, Sharon R

    2013-01-01

    Latently infected resting CD4(+) T cells are a major barrier to HIV cure. Understanding how latency is established, maintained and reversed is critical to identifying novel strategies to eliminate latently infected cells. We demonstrate here that co-culture of resting CD4(+) T cells and syngeneic myeloid dendritic cells (mDC) can dramatically increase the frequency of HIV DNA integration and latent HIV infection in non-proliferating memory, but not naïve, CD4(+) T cells. Latency was eliminated when cell-to-cell contact was prevented in the mDC-T cell co-cultures and reduced when clustering was minimised in the mDC-T cell co-cultures. Supernatants from infected mDC-T cell co-cultures did not facilitate the establishment of latency, consistent with cell-cell contact and not a soluble factor being critical for mediating latent infection of resting CD4(+) T cells. Gene expression in non-proliferating CD4(+) T cells, enriched for latent infection, showed significant changes in the expression of genes involved in cellular activation and interferon regulated pathways, including the down-regulation of genes controlling both NF-κB and cell cycle. We conclude that mDC play a key role in the establishment of HIV latency in resting memory CD4(+) T cells, which is predominantly mediated through signalling during DC-T cell contact.

  18. Myeloid dendritic cells induce HIV-1 latency in non-proliferating CD4+ T cells.

    Directory of Open Access Journals (Sweden)

    Vanessa A Evans

    Full Text Available Latently infected resting CD4(+ T cells are a major barrier to HIV cure. Understanding how latency is established, maintained and reversed is critical to identifying novel strategies to eliminate latently infected cells. We demonstrate here that co-culture of resting CD4(+ T cells and syngeneic myeloid dendritic cells (mDC can dramatically increase the frequency of HIV DNA integration and latent HIV infection in non-proliferating memory, but not naïve, CD4(+ T cells. Latency was eliminated when cell-to-cell contact was prevented in the mDC-T cell co-cultures and reduced when clustering was minimised in the mDC-T cell co-cultures. Supernatants from infected mDC-T cell co-cultures did not facilitate the establishment of latency, consistent with cell-cell contact and not a soluble factor being critical for mediating latent infection of resting CD4(+ T cells. Gene expression in non-proliferating CD4(+ T cells, enriched for latent infection, showed significant changes in the expression of genes involved in cellular activation and interferon regulated pathways, including the down-regulation of genes controlling both NF-κB and cell cycle. We conclude that mDC play a key role in the establishment of HIV latency in resting memory CD4(+ T cells, which is predominantly mediated through signalling during DC-T cell contact.

  19. Broad T Cell Immunity to the LcrV Virulence Protein is Induced by Targeted Delivery to DEC-205/CD205-Positive Mouse Dendritic Cells

    Science.gov (United States)

    2007-08-13

    Frontline: Broad T cell immunity to the LcrV virulence protein is induced by targeted delivery to DEC-205/CD205-positive mouse dendritic cells Yoonkyung...Received 30/8/07 Accepted 8/11/07 [DOI 10.1002/eji.200737799] Key words: CD205/DEC-205 Cellular immunity Dendritic cells LcrV Yersinia pestis...positive mouse dendritic cells . European Journal of Immunology 38:20 -29 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S

  20. Nocardia brasiliensis Induces Formation of Foamy Macrophages and Dendritic Cells In Vitro and In Vivo

    Science.gov (United States)

    Meester, Irene; Rosas-Taraco, Adrian Geovanni; Salinas-Carmona, Mario Cesar

    2014-01-01

    Foamy cells have been described in various infectious diseases, for example in actinomycetoma induced by Nocardia brasiliensis. These cells are generally considered to be macrophages, although they present dendritic cell (DC)-specific surface markers. In this study, we determined and confirmed the lineage of possible precursors of foamy cells in vitro and in vivo using an experimental actinomycetoma model in BALB/c mice. Bone marrow-derived macrophages (BMDM) or DC (BMDC) were infected in vitro with N. brasiliensis or labeled with carboxyfluorescein diacetate succinimidyl ester (CFSE). Both, macrophages and DC, differentiated into foamy cells after in vitro infection. CFSE-labeled BMDM or BMDC were tested for phagocytosis and CD11c/CD11b receptors markers expression before being transferred into the actinomycetoma lesion site of infected mice. In vivo studies showed that BMDM and BMDC were traced at the site where foamy cells are present in the experimental actinomycetoma. Interestingly, many of the transferred BMDM and BMDC were stained with the lipid-droplet fluorophore Nile Red. In conclusion, macrophages and DC cells can be differentiated into foamy cells in vitro and in vivo during N. brasiliensis infection. PMID:24936860

  1. Nocardia brasiliensis induces formation of foamy macrophages and dendritic cells in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Irene Meester

    Full Text Available Foamy cells have been described in various infectious diseases, for example in actinomycetoma induced by Nocardia brasiliensis. These cells are generally considered to be macrophages, although they present dendritic cell (DC-specific surface markers. In this study, we determined and confirmed the lineage of possible precursors of foamy cells in vitro and in vivo using an experimental actinomycetoma model in BALB/c mice. Bone marrow-derived macrophages (BMDM or DC (BMDC were infected in vitro with N. brasiliensis or labeled with carboxyfluorescein diacetate succinimidyl ester (CFSE. Both, macrophages and DC, differentiated into foamy cells after in vitro infection. CFSE-labeled BMDM or BMDC were tested for phagocytosis and CD11c/CD11b receptors markers expression before being transferred into the actinomycetoma lesion site of infected mice. In vivo studies showed that BMDM and BMDC were traced at the site where foamy cells are present in the experimental actinomycetoma. Interestingly, many of the transferred BMDM and BMDC were stained with the lipid-droplet fluorophore Nile Red. In conclusion, macrophages and DC cells can be differentiated into foamy cells in vitro and in vivo during N. brasiliensis infection.

  2. Nocardia brasiliensis induces formation of foamy macrophages and dendritic cells in vitro and in vivo.

    Science.gov (United States)

    Meester, Irene; Rosas-Taraco, Adrian Geovanni; Salinas-Carmona, Mario Cesar

    2014-01-01

    Foamy cells have been described in various infectious diseases, for example in actinomycetoma induced by Nocardia brasiliensis. These cells are generally considered to be macrophages, although they present dendritic cell (DC)-specific surface markers. In this study, we determined and confirmed the lineage of possible precursors of foamy cells in vitro and in vivo using an experimental actinomycetoma model in BALB/c mice. Bone marrow-derived macrophages (BMDM) or DC (BMDC) were infected in vitro with N. brasiliensis or labeled with carboxyfluorescein diacetate succinimidyl ester (CFSE). Both, macrophages and DC, differentiated into foamy cells after in vitro infection. CFSE-labeled BMDM or BMDC were tested for phagocytosis and CD11c/CD11b receptors markers expression before being transferred into the actinomycetoma lesion site of infected mice. In vivo studies showed that BMDM and BMDC were traced at the site where foamy cells are present in the experimental actinomycetoma. Interestingly, many of the transferred BMDM and BMDC were stained with the lipid-droplet fluorophore Nile Red. In conclusion, macrophages and DC cells can be differentiated into foamy cells in vitro and in vivo during N. brasiliensis infection.

  3. Effects of ceftriaxone-induced intestinal dysbacteriosis on dendritic cells of small intestine in mice.

    Science.gov (United States)

    Li, Ming; Li, Weihua; Wen, Shu; Liu, Yinhui; Tang, Li

    2013-08-01

    Intestinal microflora plays a pivotal role in the development of the innate immune system and is essential in shaping adaptive immunity. Dysbacteriosis of intestinal microflora induces altered immune responses and results in disease susceptibility. Dendritic cells (DCs), the professional antigen-presenting cells, have gained increasing attention because they connect innate and adaptive immunity. They generate both immunity in response to stimulation by pathogenic bacteria and immune tolerance in the presence of commensal bacteria. However, few studies have examined the effects of intestinal dysbacteriosis on DCs. In this study, changes of DCs in the small intestine of mice under the condition of dysbacteriosis induced by ceftriaxone sodium were investigated. It was found that intragastric administration of ceftriaxone sodium caused severe dysteriosis in mice. Compared with controls, numbers of DCs in mice with dysbacteriosis increased significantly (P = 0.0001). However, the maturity and antigen-presenting ability of DCs were greatly reduced. In addition, there was a significant difference in secretion of IL-10 and IL-12 between DCs from mice with dysbacteriosis and controls. To conclude, ceftriaxone-induced intestinal dysbacteriosis strongly affected the numbers and functions of DCs. The present data suggest that intestinal microflora plays an important role in inducing and maintaining the functions of DCs and thus is essential for the connection between innate and adaptive immune responses.

  4. Apoptotic cell-treated dendritic cells induce immune tolerance by specifically inhibiting development of CD4⁺ effector memory T cells.

    Science.gov (United States)

    Zhou, Fang; Zhang, Guang-Xian; Rostami, Abdolmohamad

    2016-02-01

    CD4(+) memory T cells play an important role in induction of autoimmunity and chronic inflammatory responses; however, regulatory mechanisms of CD4(+) memory T cell-mediated inflammatory responses are poorly understood. Here we show that apoptotic cell-treated dendritic cells inhibit development and differentiation of CD4(+) effector memory T cells in vitro and in vivo. Simultaneously, intravenous transfer of apoptotic T cell-induced tolerogenic dendritic cells can block development of experimental autoimmune encephalomyelitis (EAE), an inflammatory disease of the central nervous system in C57 BL/6J mouse. Our results imply that it is effector memory CD4(+) T cells, not central memory CD4(+) T cells, which play a major role in chronic inflammatory responses in mice with EAE. Intravenous transfer of tolerogenic dendritic cells induced by apoptotic T cells leads to immune tolerance by specifically blocking development of CD4(+) effector memory T cells compared with results of EAE control mice. These results reveal a new mechanism of apoptotic cell-treated dendritic cell-mediated immune tolerance in vivo.

  5. HIV-1 gp120 mannoses induce immunosuppressive responses from dendritic cells.

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    Meimei Shan

    2007-11-01

    Full Text Available The human immunodeficiency virus type 1 (HIV-1 envelope glycoprotein gp120 is a vaccine immunogen that can signal via several cell surface receptors. To investigate whether receptor biology could influence immune responses to gp120, we studied its interaction with human, monocyte-derived dendritic cells (MDDCs in vitro. Gp120 from the HIV-1 strain JR-FL induced IL-10 expression in MDDCs from 62% of donors, via a mannose C-type lectin receptor(s (MCLR. Gp120 from the strain LAI was also an IL-10 inducer, but gp120 from the strain KNH1144 was not. The mannose-binding protein cyanovirin-N, the 2G12 mAb to a mannose-dependent gp120 epitope, and MCLR-specific mAbs inhibited IL-10 expression, as did enzymatic removal of gp120 mannose moieties, whereas inhibitors of signaling via CD4, CCR5, or CXCR4 were ineffective. Gp120-stimulated IL-10 production correlated with DC-SIGN expression on the cells, and involved the ERK signaling pathway. Gp120-treated MDDCs also responded poorly to maturation stimuli by up-regulating activation markers inefficiently and stimulating allogeneic T cell proliferation only weakly. These adverse reactions to gp120 were MCLR-dependent but independent of IL-10 production. Since such mechanisms might suppress immune responses to Env-containing vaccines, demannosylation may be a way to improve the immunogenicity of gp120 or gp140 proteins.

  6. Serine-Rich Repeat Adhesins Contribute to Streptococcus gordonii-Induced Maturation of Human Dendritic Cells

    Science.gov (United States)

    Ko, Eun Byeol; Kim, Sun Kyung; Seo, Ho Seong; Yun, Cheol-Heui; Han, Seung Hyun

    2017-01-01

    Dendritic cells (DCs) play a pivotal role in the induction of immunity by recognition, capture, process, and presentation of antigens from infectious microbes. Streptococcus gordonii is able to cause life-threatening systemic diseases such as infective endocarditis. Serine-rich repeat (SRR) glycoproteins of S. gordonii are sialic acid-binding adhesins mediating the bacterial adherence to the host and the development of infective endocarditis. Thus, the SRR adhesins are potentially involved in the bacterial adherence to DCs and the maturation and activation of DCs required for the induction of immunity to S. gordonii. Here, we investigated the phenotypic and functional changes of human monocyte-derived DCs treated with wild-type S. gordonii or the SRR adhesin-deficient mutant. The mutant poorly bound to DCs and only weakly increased the expression of CD83, CD86, MHC class II, and PD-L1 on DCs compared with the wild-type. In addition, the mutant induced lower levels of TNF-α, IL-6, and IL-12 than the wild-type in DCs. When DCs sensitized with the mutant were co-cultured with autologous T cells, they induced weaker proliferation and activation of T cells than DCs stimulated with the wild-type. Blockade of SRR adhesin with 3′-sialyllactose markedly reduced S. gordonii binding and internalization, causing attenuation of the bacterial immunostimulatory potency in DC maturation. Collectively, our results suggest that SRR adhesins of S. gordonii are important for maturation and activation of DCs.

  7. Diet-induced obesity alters dendritic cell function in the presence and absence of tumor growth.

    Science.gov (United States)

    James, Britnie R; Tomanek-Chalkley, Ann; Askeland, Eric J; Kucaba, Tamara; Griffith, Thomas S; Norian, Lyse A

    2012-08-01

    Obesity is a mounting health concern in the United States and is associated with an increased risk for developing several cancers, including renal cell carcinoma (RCC). Despite this, little is known regarding the impact of obesity on antitumor immunity. Because dendritic cells (DC) are critical regulators of antitumor immunity, we examined the combined effects of obesity and tumor outgrowth on DC function. Using a diet-induced obesity (DIO) model, DC function was evaluated in mice bearing orthotopic RCC and in tumor-free controls. Tumor-free DIO mice had profoundly altered serum cytokine and chemokine profiles, with upregulation of 15 proteins, including IL-1α, IL-17, and LIF. Tumor-free DIO mice had elevated percentages of conventional splenic DC that were impaired in their ability to stimulate naive T cell expansion, although they were phenotypically similar to normal weight (NW) controls. In DIO mice, intrarenal RCC tumor challenge in the absence of therapy led to increased local infiltration by T cell-suppressive DC and accelerated early tumor outgrowth. Following administration of a DC-dependent immunotherapy, established RCC tumors regressed in normal weight mice. The same immunotherapy was ineffective in DIO mice and was characterized by an accumulation of regulatory DC in tumor-bearing kidneys, decreased local infiltration by IFN-γ-producing CD8 T cells, and progressive tumor outgrowth. Our results suggest that the presence of obesity as a comorbidity can impair the efficacy of DC-dependent antitumor immunotherapies.

  8. Excretory-secretory products (ESP) from Fasciola hepatica induce tolerogenic properties in myeloid dendritic cells.

    Science.gov (United States)

    Falcón, Cristian; Carranza, Franco; Martínez, Fernando F; Knubel, Carolina P; Masih, Diana T; Motrán, Claudia C; Cervi, Laura

    2010-09-15

    Fasciola hepatica is a helminth trematode that migrates through the host tissues until reaching bile ducts where it becomes an adult. During its migration the parasite releases different excretory-secretory products (ESP), which are in contact with the immune system. In this study, we focused on the effect of ESP on the maturation and function of murine bone marrow derived-dendritic cells (DC). We found that the treatment of DC with ESP failed to induce a classical maturation of these cells, since ESP alone did not activate DC to produce any cytokines, although they impaired the ability of DC to be activated by TLR ligands and also their capacity to stimulate an allospecific response. In addition, using an in vitro ovalbumin peptide-restricted priming assay, ESP-treated DC exhibited a capacity to drive Th2 and regulatory T cell (Treg) polarization of CD4(+) cells from DO11.10 transgenic mice. This was characterized by increased IL-4, IL-5, IL-10 and TGF-beta production and the expansion of CD4(+)CD25(+)Foxp3(+) cells. Our results support the hypothesis that ESP from F. hepatica modulate the maturation and function of DC as part of a generalized immunosuppressive mechanism that involves a bias towards a Th2 response and Treg development.

  9. Dendritic morphology, synaptic transmission, and activity of mature granule cells born following pilocarpine-induced status epilepticus in the rat

    Directory of Open Access Journals (Sweden)

    Fei eGao

    2015-10-01

    Full Text Available To understand the potential role of enhanced hippocampal neurogenesis after pilocarpine-induced status epilepticus (SE in the development of epilepsy, we quantitatively analyzed the geometry of apical dendrites, synaptic transmission, and activation levels of normotopically distributed mature newborn granule cells in the rat.SE in male Sprague-Dawley rats lasting for more than 2 hours was induced by an intraperitoneal injection of pilocarpine. The complexity, spine density, miniature post-synaptic currents, and activity-regulated cytoskeleton-associated protein (Arc expression of granule cells born five days after SE were studied at least 10 weeks after CAG-GFP retroviral vector-mediated labeling.Mature granule cells born after SE had dendritic complexity similar to that of granule cells born naturally, but with denser mushroom-like spines in dendritic segments located in the outer molecular layer. Miniature inhibitory post-synaptic currents (mIPSCs were similar between the controls and rats subjected to SE; however, smaller miniature excitatory post-synaptic current (mEPSC amplitude with a trend toward less frequent was found in mature granule cells born after SE. After maturation, granule cells born after SE did not show denser Arc expression in the resting condition or after being activated by transient seizure activity than vicinal GFP-unlabeled granule cells.Thus our results suggest that normotopic granule cells born after pilocarpine-induced SE are no more active when mature than age-matched, naturally born granule cells.

  10. Perforin enhances the granulysin-induced lysis of Listeria innocua in human dendritic cells

    Directory of Open Access Journals (Sweden)

    Wagner Carsten A

    2007-08-01

    Full Text Available Abstract Background Cytotoxic T lymphocytes (CTL and natural killer (NK cells play an essential role in the host defence against intracellular pathogens such as Listeria, and Mycobacteria. The key mediator of bacteria-directed cytotoxicity is granulysin, a 9 kDa protein stored in cytolytic granules together with perforin and granzymes. Granulysin binds to cell membranes and is subsequently taken up via a lipid raft-associated mechanism. In dendritic cells (DC granulysin is further transferred via early endosomes to L. innocua-containing phagosomes were bacteriolysis is induced. In the present study we analysed the role of perforin in granulysin-induced intracellular bacteriolysis in DC. Results We found granulysin-induced lysis of intracellular Listeria significantly increased when perforin was simultaneously present. In pulse-chase experiments enhanced bacteriolysis was observed when perforin was added up to 25 minutes after loading the cells with granulysin demonstrating no ultimate need for simultaneous uptake of granulysin and perforin. The perforin concentration sufficient to enhance granulysin-induced intracellular bacteriolysis did not cause permanent membrane pores in Listeria-challenged DC as shown by dye exclusion test and LDH release. This was in contrast to non challenged DC that were more susceptible to perforin lysis. For Listeria-challenged DC, there was clear evidence for an Ca2+ influx in response to sublytic perforin demonstrating a short-lived change in the plasma membrane permeability. Perforin treatment did not affect granulysin binding, initial uptake or intracellular trafficking to early endosomes. However, enhanced colocalization of granulysin with listerial DNA in presence of perforin was found by confocal laser scanning microscopy. Conclusion The results provide evidence that perforin increases granulysin-mediated killing of intracellular Listeria by enhanced phagosome-endosome fusion triggered by a transient Ca2+ flux.

  11. p38 Mitogen-Activated Protein Kinase in beryllium-induced dendritic cell activation.

    Science.gov (United States)

    Li, L; Huang, Z; Gillespie, M; Mroz, P M; Maier, L A

    2014-12-01

    Dendritic cells (DC) play a role in the regulation of immune responses to haptens, which in turn impact DC maturation. Whether beryllium (Be) is able to induce DC maturation and if this occurs via the MAPK pathway is not known. Primary monocyte-derived DCs (moDCs) models were generated from Be non-exposed healthy volunteers as a non-sensitized cell model, while PBMCs from BeS (Be sensitized) and CBD (chronic beryllium disease) were used as disease models. The response of these cells to Be was evaluated. The expression of CD40 was increased significantly (pBeSO₄-stimulation. BeSO₄ induced p38MAPK phosphorylation, while IκB-α was degraded in Be-stimulated moDCs. The p38 MAPK inhibitor SB203580 blocked Be-induced NF-κB activation in moDCs, suggesting that p38MAPK and NF-κB are dependently activated by BeSO₄. Furthermore, in BeS and CBD subjects, SB203580 downregulated Be-stimulated proliferation in a dose-dependent manner, and decreased Be-stimulated TNF-α and IFNγ cytokine production. Taken together, this study suggests that Be-induces non-sensitized Glu69+ DCs maturation, and that p38MAPK signaling is important in the Be-stimulated DCs activation as well as subsequent T cell proliferation and cytokine production in BeS and CBD. In total, the MAPK pathway may serve as a potential therapeutic target for human granulomatous lung diseases.

  12. Diet-Derived Short Chain Fatty Acids Stimulate Intestinal Epithelial Cells To Induce Mucosal Tolerogenic Dendritic Cells.

    Science.gov (United States)

    Goverse, Gera; Molenaar, Rosalie; Macia, Laurence; Tan, Jian; Erkelens, Martje N; Konijn, Tanja; Knippenberg, Marlene; Cook, Emma C L; Hanekamp, Diana; Veldhoen, Marc; Hartog, Anita; Roeselers, Guus; Mackay, Charles R; Mebius, Reina E

    2017-03-01

    The gastrointestinal tract is continuously exposed to many environmental factors that influence intestinal epithelial cells and the underlying mucosal immune system. In this article, we demonstrate that dietary fiber and short chain fatty acids (SCFAs) induced the expression of the vitamin A-converting enzyme RALDH1 in intestinal epithelial cells in vivo and in vitro, respectively. Furthermore, our data showed that the expression levels of RALDH1 in small intestinal epithelial cells correlated with the activity of vitamin A-converting enzymes in mesenteric lymph node dendritic cells, along with increased numbers of intestinal regulatory T cells and a higher production of luminal IgA. Moreover, we show that the consumption of dietary fiber can alter the composition of SCFA-producing microbiota and SCFA production in the small intestines. In conclusion, our data illustrate that dietary adjustments affect small intestinal epithelial cells and can be used to modulate the mucosal immune system.

  13. Pulmonary infections in swine induce altered porcine surfactant protein D expression and localization to dendritic cells in bronchial-associated lymphoid tissue

    DEFF Research Database (Denmark)

    Sørensen, C.M.; Holmskov, U.; Aalbæk, B.

    2005-01-01

    and with dendritic cells in microbial-induced BALT. The function of the interaction between pSP-D and dendritic cells in BALT remain unclear, but pSP-D could represent a link between the innate and adaptive immune system, facilitating the bacterial antigen presentation by dendritic cells in BALT.......Surfactant protein D (SP-D) is a pattern-recognition molecule of the innate immune system that recognizes various microbial surface-specific carbohydrate and lipid patterns. In vitro data has suggested that this binding may lead to increased microbial association with macrophages and dendritic...

  14. Influence of autologous dendritic cells on cytokine-induced killer cell proliferation, cell phenotype and antitumor activity in vitro.

    Science.gov (United States)

    Cao, Jingsong; Chen, Cong; Wang, Yuhuan; Chen, Xuecheng; Chen, Zeying; Luo, Xiaoling

    2016-09-01

    Dendritic cell (DCs) are essential antigen processing and presentation cells that play a key role in the immune response. In this study, DCs were co-cultured with cytokine-induced killer cells (DC-CIKs) in vitro to detect changes in cell proliferation, cell phenotype and cell cytotoxicity. The results revealed that the DCs were suitable for co-culture with CIKs at day 7, and that cell quantity of DC-CIKs was lower than that of CIKs until day 11, but it was significantly improved to 1.17-fold that of CIKs at day 13. Flow cytometry was used to detect the cell phenotype of CIKs and DC-CIKs. Compared with CIKs at day 13, the percentage of CD3(+), CD3(+)CD4(+), CD3(+)CD8(+) and CD3(+)CD56(+) T cells in DC-CIKs was significantly improved 1.02, 1.79, 1.26 and 2.44-fold, respectively. In addition, trypan blue staining analysis demonstrated that the cell viability of CIKs and DC-CIKs was 96% and 98%, respectively. Furthermore, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) analysis verified that CIK and DC-CIK cytotoxicity in Hela cells was 58% and 80%, respectively, with a significant difference. Taken together, our results indicate that the cell proliferation, cell phenotype and antitumor activity of CIKs were all enhanced following co-culture with DCs in vitro. These results are likely to be useful for DC-CIK application in antitumor therapies.

  15. The anti-spasticity drug baclofen alleviates collagen-induced arthritis and regulates dendritic cells.

    Science.gov (United States)

    Huang, Shichao; Mao, Jianxin; Wei, Bin; Pei, Gang

    2015-07-01

    Baclofen is used clinically as a drug that treats spasticity, which is a syndrome characterized by excessive contraction of the muscles and hyperflexia in the central nervous system (CNS), by activating GABA(B) receptors (GABA(B)Rs). Baclofen was recently reported to desensitize chemokine receptors and to suppress inflammation through the activation of GABA(B)Rs. GABA(B)Rs are expressed in various immune cells, but the functions of these receptors in autoimmune diseases remain largely unknown. In this study, we investigated the effects of baclofen in murine collagen-induced arthritis (CIA). Oral administration of baclofen alleviated the clinical development of CIA, with a reduced number of IL-17-producing T helper 17 (T(H)17) cells. In addition, baclofen treatment suppressed dendritic cell (DC)-primed T(H)17 cell differentiation by reducing the production of IL-6 by DCs in vitro. Furthermore, the pharmacological and genetic blockade of GABA(B)Rs in DCs weakened the effects of baclofen, indicating that GABA(B)Rs are the molecular targets of baclofen on DCs. Thus, our findings revealed a potential role for baclofen in the treatment of CIA, as well as a previously unknown signaling pathway that regulates DC function.

  16. Pathogen-Associated Molecular Patterns Induced Crosstalk between Dendritic Cells, T Helper Cells, and Natural Killer Helper Cells Can Improve Dendritic Cell Vaccination.

    Science.gov (United States)

    Oth, Tammy; Vanderlocht, Joris; Van Elssen, Catharina H M J; Bos, Gerard M J; Germeraad, Wilfred T V

    2016-01-01

    A coordinated cellular interplay is of crucial importance in both host defense against pathogens and malignantly transformed cells. The various interactions of Dendritic Cells (DC), Natural Killer (NK) cells, and T helper (Th) cells can be influenced by a variety of pathogen-associated molecular patterns (PAMPs) and will lead to enhanced CD8(+) effector T cell responses. Specific Pattern Recognition Receptor (PRR) triggering during maturation enables DC to enhance Th1 as well as NK helper cell responses. This effect is correlated with the amount of IL-12p70 released by DC. Activated NK cells are able to amplify the proinflammatory cytokine profile of DC via the release of IFN-γ. The knowledge on how PAMP recognition can modulate the DC is of importance for the design and definition of appropriate therapeutic cancer vaccines. In this review we will discuss the potential role of specific PAMP-matured DC in optimizing therapeutic DC-based vaccines, as some of these DC are efficiently activating Th1, NK cells, and cytotoxic T cells. Moreover, to optimize these vaccines, also the inhibitory effects of tumor-derived suppressive factors, for example, on the NK-DC crosstalk, should be taken into account. Finally, the suppressive role of the tumor microenvironment in vaccination efficacy and some proposals to overcome this by using combination therapies will be described.

  17. Plasmodium falciparum-Derived Uric Acid Precipitates Induce Maturation of Dendritic Cells

    Science.gov (United States)

    van de Hoef, Diana L.; Coppens, Isabelle; Holowka, Thomas; Ben Mamoun, Choukri; Branch, OraLee; Rodriguez, Ana

    2013-01-01

    Malaria is characterized by cyclical fevers and high levels of inflammation, and while an early inflammatory response contributes to parasite clearance, excessive and persistent inflammation can lead to severe forms of the disease. Here, we show that Plasmodium falciparum-infected erythrocytes contain uric acid precipitates in the cytoplasm of the parasitophorous vacuole, which are released when erythrocytes rupture. Uric acid precipitates are highly inflammatory molecules that are considered a danger signal for innate immunity and are the causative agent in gout. We determined that P. falciparum-derived uric acid precipitates induce maturation of human dendritic cells, increasing the expression of cell surface co-stimulatory molecules such as CD80 and CD86, while decreasing human leukocyte antigen-DR expression. In accordance with this, uric acid accounts for a significant proportion of the total stimulatory activity induced by parasite-infected erythrocytes. Moreover, the identification of uric acid precipitates in P. falciparum- and P. vivax-infected erythrocytes obtained directly from malaria patients underscores the in vivo and clinical relevance of our findings. Altogether, our data implicate uric acid precipitates as a potentially important contributor to the innate immune response to Plasmodium infection and may provide a novel target for adjunct therapies. PMID:23405174

  18. Ebola and Marburg Viruses Replicate in Monocyle- Derived Dendritic Cells without Inducing the Production of Cytokines and Full Maturation

    Science.gov (United States)

    2007-11-02

    secretion in response to a second IFN-inducing stimulus ( replication -defective alphavirus ) was also potently inhibited by both viruses. From these data...1630 • JID 2003:188 (1 December) • Bosio et al. M A J O R A R T I C L E Ebola and Marburg Viruses Replicate in Monocyte- Derived Dendritic Cells...immune responses. We demonstrate that EBOV and MARV infected and replicated in primary human DCs without inducing cytokine secretion. Infected DC

  19. Inflammation in lung after acute myocardial infarction is induced by dendritic cell-mediated immune response.

    Science.gov (United States)

    Hu, L J; Ren, W Y; Shen, Q J; Ji, H Y; Zhu, L

    2017-01-01

    The present study was performed to describe the changes of lung tissues in mice with acute myocardial infarction (AMI) and also explain the cell mechanism involved in inflammation in lung. AMI was established by left coronary ligation in mice. Then mice were divided into three groups: control group, MW1 group (sampling after surgery for one week) and MW2 group (sampling after surgery for two weeks). Afterwards, measurement of lung weight and lung histology, cell sorting in bronchoalveolar lavage (BAL) fluid and detection of several adhesive molecules, inflammatory molecules as well as enzyme associated with inflammation were performed. Moreover, dendritic cells (DCs) were isolated from bone marrow of C57B/L6 mice. After incubating with necrotic myocardium, the expression of antigen presenting molecules, co-stimulatory molecules and inflammatory molecules were detected by flow cytometry or immunohistochemistry in DCs. We also detected T-cell proliferation after incubating with necrotic myocardium-treated DCs. AMI induced pathological changes of lung tissue and increased inflammatory cell amount in BAL fluid. AMI also increased the expression of several inflammatory factors, adhesive molecules and enzymes associated with inflammation. CD11c and TLR9, which are DC surface markers, showed a significantly increased expression in mice with AMI. Additionally, necrotic myocardium significantly increased the expression of co-stimulatory factors including CD83 and CD80, inflammatory cytokines including TNF-α, IFN-γ and NF-κB in DCs. Furthermore, DCs treated with necrotic myocardium also significantly promoted T-cell proliferation. AMI induced inflammation in lung and these pathological changes were mediated by DC-associated immune response.

  20. Cytokine-induced killer cells interact with tumor lysate-pulsed dendritic cells via CCR5 signaling.

    Science.gov (United States)

    Lee, Hong Kyung; Kim, Yong Guk; Kim, Ji Sung; Park, Eun Jae; Kim, Boyeong; Park, Ki Hwan; Kang, Jong Soon; Hong, Jin Tae; Kim, Youngsoo; Han, Sang-Bae

    2016-08-10

    The antitumor activity of cytokine-induced killer (CIK) cells can be increased by co-culturing them with tumor lysate-pulsed dendritic cells (tDCs); this phenomenon has been studied mainly at the population level. Using time-lapse imaging, we examined how CIK cells gather information from tDCs at the single-cell level. tDCs highly expressed CCL5, which bound CCR5 expressed on CIK cells. tDCs strongly induced migration of Ccr5(+/+) CIK cells, but not that of Ccr5(-/-) CIK cells or Ccr5(+/+) CIK cells treated with the CCR5 antagonist Maraviroc. Individual tDCs contacted Ccr5(+/+) CIK cells more frequently and lengthily than with Ccr5(-/-) CIK cells. Consequently, tDCs increased the antitumor activity of Ccr5(+/+) CIK cells in vitro and in vivo, but did not increase that of Ccr5(-/-) CIK cells. Taken together, our data provide insight into the mechanism of CIK cell activation by tDCs at the single-cell level.

  1. Whole Body Irradiation Induces Cutaneous Dendritic Cells Depletion via NF-κB Activation

    Directory of Open Access Journals (Sweden)

    Yanyong Yang

    2013-07-01

    Full Text Available Background: Effect of ionizing radiation on cutaneous dendritic cells (cDC is critical to its influence on immune status of the skin, which plays an important role in the progression and recovery of radiation skin sickness. This study was to study the influence of whole body irradiation (WBI on the cDC. Methods: Density of epidermal and dermal DC was determined with a fluorescent microscopy and the DC numbers in lymph node were measured by flow cytometry. A FITC induced migration assay was also used to study the migration of DC. The expressions of cytokines and chemokines were evaluated by Realtime PCR, and the protein level of was measured by Western blot. Results: WBI caused depletion of cDC in epidermal as well as dermal and augmented FITC-induced migration of DC to the draining lymph node (LN. The number of DC migrated from ear explants to the CCL19-containing medium also increased after exposure to WBI. It was also found that WBI increased mRNA level of CCL19/CCL21 as well as CCR7 in LN and skin tissue. The expressions of TNFa, IL-1a, IL-1ß, and IL-6 in skin tissues were also greatly induced by WBI in a dose dependent manner. Finally, we found that WBI induced translocation of nuclear factor κB (NF-κB and that the radiation-induced migration of DC was blocked by NF-κB inhibitor or TLR4 knockout. Conclusion: WBI caused cDC depletion through induction of DC migration to the draining LN, which might result from the activation of NF-κB and the induction of inflammatory microenvironment within the skin.

  2. Ceramide formation is involved in Lactobacillus acidophilus-induced IFN-beta response in dendritic cells

    DEFF Research Database (Denmark)

    Fuglsang, Eva; Henningsen, Louise; Frøkiær, Hanne

    The sphingolipid ceramide is known to play a role in lipid raft fusion and receptor clustering in the plasma membrane (PM). Upon bacterial encounter, dendritic cells (DCs) endocytose the bacteria and initiate a bacteria-specific downstream signaling event. We hypothesized that conversion...

  3. Interleukin-10 modified dendritic cells induce allo-hyporesponsiveness and prolong small intestine allograft survival

    Institute of Scientific and Technical Information of China (English)

    Min Zhu; Ming-Fa Wei; Fang Liu; Hui-Fen Shi; Guo Wang

    2003-01-01

    AIM: To investigate whether TL-10-transduced dendritic cells (DCs) could induce tolerogenicity and prolong allograft survival in rat intestinal transplantation.METHODS: Spleen-derived DCs were prepared and genetically modified by hTL-10 gene. The level of IL-10 expression was quantitated by ELTSA. DC function was assessed by MTT in mixed leukocyte reaction. Allogeneic T-cell apoptosis was examined by flow cytometric analysis. Seven days before heterotopic intestinal transplantation, 2x106 donor-derived IL-10-DC were injected intravenously, then transplantation was performed between SD donor and Wistar recipient.RESULTS: Compared with untransduced DC, IL-10-DC could suppress allogeneic mixed leukocyte reaction (MLR). The inhibitory effect was the most striking with the stimulator/effector (S/F) ratio of 1:10. The inhibition rate was 33.25 %,41.19 % (P<0.01) and 22.92 % with the S/E ratio of 1:1,1:10 and 1:50 respectively. At 48 hours and 72 hours by flow cytometry counting, apoptotic T cells responded to IL-10-DC in MLR were 13.8 % and 30.1%, while untransduced group did not undergo significant apoptosis (P<0.05). IL-10-DC pretreated recipients had a moderate survival prolongation with a mean allograft survival of 19.8 days (P<0.01),compared with 7.3±2.4 days in control group and 8.3±2.9days in untransduced DC group. Rejection occurred in the control group within three days. The difference between untreated DC group and control group was not significant.CONCLUSION: IL-10-DC can induce allogenic T-cell hyporesponsiveness in vitro and apoptosis may be involved in it. IL-10-DC pretreatment can prolong intestinal allograft survival in the recipient.

  4. Neutrophil extracellular traps downregulate lipopolysaccharide-induced activation of monocyte-derived dendritic cells.

    Science.gov (United States)

    Barrientos, Lorena; Bignon, Alexandre; Gueguen, Claire; de Chaisemartin, Luc; Gorges, Roseline; Sandré, Catherine; Mascarell, Laurent; Balabanian, Karl; Kerdine-Römer, Saadia; Pallardy, Marc; Marin-Esteban, Viviana; Chollet-Martin, Sylvie

    2014-12-01

    Polymorphonuclear neutrophils (PMN) play a central role in inflammation and participate in its control, notably by modulating dendritic cell (DC) functions via soluble mediators or cell-cell contacts. Neutrophil extracellular traps (NETs) released by PMN could play a role in this context. To evaluate NET effects on DC maturation, we developed a model based on monocyte-derived DC (moDC) and calibrated NETs isolated from fresh human PMN. We found that isolated NETs alone had no discernable effect on moDC. In contrast, they downregulated LPS-induced moDC maturation, as shown by decreased surface expression of HLA-DR, CD80, CD83, and CD86, and by downregulated cytokine production (TNF-α, IL-6, IL-12, IL-23), with no increase in the expression of tolerogenic DC genes. Moreover, the presence of NETs during moDC maturation diminished the capacity of these moDC to induce T lymphocyte proliferation in both autologous and allogeneic conditions, and modulated CD4(+) T lymphocyte polarization by promoting the production of Th2 cytokines (IL-5 and IL-13) and reducing that of Th1 and Th17 cytokines (IFN-γ and IL-17). Interestingly, the expression and activities of the lymphoid chemokine receptors CCR7 and CXCR4 on moDC were not altered when moDC matured in the presence of NETs. Together, these findings reveal a new role for NETs in adaptive immune responses, modulating some moDC functions and thereby participating in the control of inflammation.

  5. Dendritic cells induce Tc1 cell differentiation via the CD40/CD40L pathway in mice after exposure to cigarette smoke.

    Science.gov (United States)

    Kuang, Liang-Jian; Deng, Ting-Ting; Wang, Qin; Qiu, Shi-Lin; Liang, Yi; He, Zhi-Yi; Zhang, Jian-Quan; Bai, Jing; Li, Mei-Hua; Deng, Jing-Min; Liu, Guang-Nan; Liu, Ji-Feng; Zhong, Xiao-Ning

    2016-09-01

    Dendritic cells and CD8(+) T cells participate in the pathology of chronic obstructive pulmonary disease, including emphysema, but little is known of the involvement of the CD40/CD40L pathway. We investigated the role of the CD40/CD40L pathway in Tc1 cell differentiation induced by dendritic cells in a mouse model of emphysema, and in vitro. C57BL/6J wild-type and CD40(-/-) mice were exposed to cigarette smoke (CS) or not (control), for 24 wk. In vitro experiments involved wild-type and CD40(-/-) dendritic cells treated with CS extract (CSE) or not. Compared with the control groups, the CS mice (both wild type and CD40(-/-)) had a greater percentage of lung dendritic cells and higher levels of major histocompatability complex (MHC) class I molecules and costimulatory molecules CD40 and CD80. Relative to the CS CD40(-/-) mice, the CS wild type showed greater signs of lung damage and Tc1 cell differentiation. In vitro, the CSE-treated wild-type cells evidenced more cytokine release (IL-12/p70) and Tc1 cell differentiation than did the CSE-treated CD40(-/-) cells. Exposure to cigarette smoke increases the percentage of lung dendritic cells and promotes Tc1 cell differentiation via the CD40/CD40L pathway. Blocking the CD40/CD40L pathway may suppress development of emphysema in mice exposed to cigarette smoke.

  6. Whole inactivated avian Influenza H9N2 viruses induce nasal submucosal dendritic cells to sample luminal viruses via transepithelial dendrites and trigger subsequent DC maturation.

    Science.gov (United States)

    Qin, Tao; Yin, Yinyan; Wang, Xiaoqing; Liu, Haofei; Lin, Jian; Yu, Qinghua; Yang, Qian

    2015-03-10

    Nasal mucosal barrier is a key impediment for the absorption of influenza whole inactivated virus (WIV) intranasal vaccine. Yet it is still unclear how WIV cross the epithelial cells (ECs) in nasal cavity. Here, in vitro, a coculture system was well established, consisting of surrogate nasal ECs (Calu-3) and dendritic cells (DCs). After adding H9N2 WIV on the apical side of ECs, we found that submucosal DCs extended their transepithelial dendrites (TEDs) and sampled luminal viruses. However, ECs were not involved in the transepithelial transport of viruses. Subsequently, the phenotypic and functional maturation of DCs were also enhanced, whereas they were attenuated after blocking of TED formation by anti-JAM1 antibody. In vivo, we confirmed that H9N2 WIV were capable of inducing nasal submucosal DCs to sample luminal viruses via TEDs in the nasal passage but not nasal-associated lymphoid tissue (NALT). CD103(+) and CD103(-) DC subsets participated in this process. Of note, chemokine CCL20, released from the H9N2 WIV-induced ECs, played a vital role in DC recruitment and TED formation. Taken together, our findings indicated that TEDs played a critical role in facilitating viral transport across the epithelial barrier, which may guide the design of novel nasal mucosal vaccine strategies.

  7. Class 3 semaphorins induce F-actin reorganization in human dendritic cells: Role in cell migration.

    Science.gov (United States)

    Curreli, Sabrina; Wong, Bin Sheng; Latinovic, Olga; Konstantopoulos, Konstantinos; Stamatos, Nicholas M

    2016-12-01

    Class 3 semaphorins (Semas) are soluble proteins that are well recognized for their role in guiding axonal migration during neuronal development. In the immune system, Sema3A has been shown to influence murine dendritic cell (DC) migration by signaling through a neuropilin (NRP)-1/plexin-A1 coreceptor axis. Potential roles for class 3 Semas in human DCs have yet to be described. We tested the hypothesis that Sema3A, -3C, and -3F, each with a unique NRP-1 and/or NRP-2 binding specificity, influence human DC migration. In this report, we find that although NRP-1 and NRP-2 are expressed in human immature DCs (imDCs), NRP-2 expression increases as cells mature further, whereas expression of NRP-1 declines dramatically. Elevated levels of RNA encoding plexin-A1 and -A3 are present in both imDCs and mature DC (mDCs), supporting the relevance of Sema/NRP/plexin signaling pathways in these cells. Sema3A, -3C, and -3F bind to human DCs, with Sema3F binding predominantly through NRP-2. The binding of these Semas leads to reorganization of actin filaments at the plasma membrane and increased transwell migration in the absence or presence of chemokine CCL19. Microfluidic chamber assays failed to demonstrate consistent changes in speed of Sema3C-treated DCs, suggesting increased cell deformability as a possible explanation for enhanced transwell migration. Although monocytes express RNA encoding Sema3A, -3C, and -3F, only RNA encoding Sema3C increases robustly during DC differentiation. These data suggest that Sema3A, -3C, and -3F, likely with coreceptors NRP-1, NRP-2, and plexin-A1 and/or -A3, promote migration and possibly other activities of human DCs during innate and adaptive immune responses.

  8. Structural, phenotypic and functional maturation of bone marrow dendritic cells (BMDCs) induced by Chitosan (CTS).

    Science.gov (United States)

    Jia, Lihui; Gao, Xinghua; Wang, Yiqing; Yao, Na; Zhang, Xiaodong

    2014-11-01

    The objective of the present work was to explore the effect of CTS on structural, phenotypic and functional maturation of murine bone marrow derived dendritic cells (BMDCs). The maturity of BMDCs post treatment with CTS was evaluated using transmission electron microscopy (TEM) for structure changes, flow cytometry (FCM) for changes of key surface molecules, FITC-dextran bio-assay for phagocytosis, test of acid phosphatase activity (ACP) for biochemical changes and enzyme linked immunosorbent assay (ELISA) for cytokine level. We found that CTS downregulated the numbers of phagosomes inside the BMDCs, up-regulated the expression of MHC II, CD40, CD83, CD80 and CD86 molecules on BMDCs, decreased activity of ACP and phagocytosis by BMDCs, and induced production of higher levels of IL-12 and TNF-α. It was therefore confirmed that CTS could effectively promote the maturation of BMDCs. Our study provided more detailed evidence and rationale to support the application of CTS as an immune stimulator for enhancing host immunity and as an adjuvant in the design of DC-based vaccines.

  9. Three-dimensional Quantification of Dendritic Spines from Pyramidal Neurons Derived from Human Induced Pluripotent Stem Cells.

    Science.gov (United States)

    Gouder, Laura; Tinevez, Jean-Yves; Goubran-Botros, Hany; Benchoua, Alexandra; Bourgeron, Thomas; Cloëz-Tayarani, Isabelle

    2015-10-10

    Dendritic spines are small protrusions that correspond to the post-synaptic compartments of excitatory synapses in the central nervous system. They are distributed along the dendrites. Their morphology is largely dependent on neuronal activity, and they are dynamic. Dendritic spines express glutamatergic receptors (AMPA and NMDA receptors) on their surface and at the levels of postsynaptic densities. Each spine allows the neuron to control its state and local activity independently. Spine morphologies have been extensively studied in glutamatergic pyramidal cells of the brain cortex, using both in vivo approaches and neuronal cultures obtained from rodent tissues. Neuropathological conditions can be associated to altered spine induction and maturation, as shown in rodent cultured neurons and one-dimensional quantitative analysis (1). The present study describes a protocol for the 3D quantitative analysis of spine morphologies using human cortical neurons derived from neural stem cells (late cortical progenitors). These cells were initially obtained from induced pluripotent stem cells. This protocol allows the analysis of spine morphologies at different culture periods, and with possible comparison between induced pluripotent stem cells obtained from control individuals with those obtained from patients with psychiatric diseases.

  10. Plasmacytoid dendritic cells prevent cigarette smoke and Chlamydophila pneumoniae-induced Th2 inflammatory responses.

    Science.gov (United States)

    Sorrentino, Rosalinda; Gray, Pearl; Chen, Shuang; Shimada, Kenichi; Crother, Timothy R; Arditi, Moshe

    2010-10-01

    Smoking promotes the development of allergic asthma and pneumonia. Chlamydophila pneumoniae lung infection is associated with an increased risk for asthma, inducing an immune response regulated by dendritic cells (DCs). This study sought to determine whether exposure to cigarette smoke modulates the functional activity of CD11c-positive DCs in the lung, with and without concomitant C. pneumoniae infection. Bone marrow-derived DCs (BMDCs) were exposed in vitro to cigarette smoke extract (CSE) and/or live C. pneumoniae (Cpn), and then adoptively transferred intratracheally into wild-type mice. Although CSE plus Cpn appeared to exert an additive effect on the production of Th2 cytokines in vitro, we did not see this effect in vivo. However, the adoptive transfer of DCs pulsed with both CSE and C. pneumoniae into the lungs of naive mice led to an influx of plasmacytoid DCs (pDCs) that suppressed the Th2 skewing ability of the transferred BMDCs. The depletion of pDCs by antibody restored the Th2 skewing ability of the BMDCs. The expression of indoleamine-2,3-dioxygenase in the lung was reduced after the depletion of pDCs, and blocking IFN-α in vitro prevented the ability of pDCs to inhibit the Th2 responses induced by myeloid DCs (mDCs), suggesting their potential involvement in the mechanism of altered polarization. In conclusion, exposure to cigarette smoke skews C. pneumoniae-induced mDCs responses toward a Th2 bias in the lung, which is prevented by pDCs. We propose that pDCs may play a major role in the immunosuppressive lung environment in smokers with C. pneumoniae infection.

  11. Mesenteric lymph node CD11b(-) CD103(+) PD-L1(High) dendritic cells highly induce regulatory T cells.

    Science.gov (United States)

    Shiokawa, Aya; Kotaki, Ryutaro; Takano, Tomohiro; Nakajima-Adachi, Haruyo; Hachimura, Satoshi

    2017-09-01

    Dendritic cells (DCs) in mesenteric lymph nodes (MLNs) induce Foxp3(+) regulatory T cells to regulate immune responses to beneficial or non-harmful agents in the intestine, such as commensal bacteria and foods. Several studies in MLN DCs have revealed that the CD103(+) DC subset highly induces regulatory T cells, and another study has reported that MLN DCs from programmed death ligand 1 (PD-L1) -deficient mice could not induce regulatory T cells. Hence, the present study investigated the expression of these molecules on MLN CD11c(+) cells. Four distinct subsets expressing CD103 and/or PD-L1 were identified, namely CD11b(+) CD103(+) PD-L1(High) , CD11b(-) CD103(+) PD-L1(High) , CD11b(-) CD103(+) PD-L1(Low) and CD11b(+) CD103(-) PD-L1(Int) . Among them, the CD11b(-) CD103(+) PD-L1(High) DC subset highly induced Foxp3(+) T cells. This subset expressed Aldh1a2 and Itgb8 genes, which are involved in retinoic acid metabolism and transforming growth factor-β (TGF-β) activation, respectively. Exogenous TGF-β supplementation equalized the level of Foxp3(+) T-cell induction by the four subsets whereas retinoic acid did not, which suggests that high ability to activate TGF-β is determinant for the high Foxp3(+) T-cell induction by CD11b(-) CD103(+) PD-L1(High) DC subset. Finally, this subset exhibited a migratory DC phenotype and could take up and present orally administered antigens. Collectively, the MLN CD11b(-) CD103(+) PD-L1(High) DC subset probably takes up luminal antigens in the intestine, migrates to MLNs, and highly induces regulatory T cells through TGF-β activation. © 2017 John Wiley & Sons Ltd.

  12. Induction of anti-tumor CD8 T cell responses by experimental ECP-induced human dendritic antigen presenting cells.

    Science.gov (United States)

    Kibbi, N; Sobolev, O; Girardi, M; Edelson, R L

    2016-08-01

    Extracorporeal photochemotherapy (ECP), or photopheresis, is distinguished by the specificity of the clinically potent immunologic reactions it initiates or regulates. The selectivity of ECP-induced immunoprotection for the malignant clone in cutaneous T cell lymphoma (CTCL), and for the pathogenic clones in allograft rejection and graft-versus-host disease (GVHD), has suggested a central mechanistic role for dendritic antigen presenting cells (DC). Discovery of ECP's induction of monocyte-derived DC, via monocyte signaling by ECP-plate activated platelets, and the absolute dependency of experimental ECP on such induced DC, supports that premise. Herein, we show that ECP-induced DC are capable of stimulating CD8 T cell responses to tumor antigens with which they are loaded. They internalize an antigen-specific melanoma-associated protein then present it onto a class I major histocompatibility, which then stimulates expansion of anti-tumor CD8 T cell populations. We conclude that ECP-induced DC prominently contribute to its initiation of anti-tumor immunity and raise the possibility that the therapy may be applicable to the immunotherapeutic management of a broader spectrum of cancers.

  13. Mouse dendritic cells pulsed with capsular polysaccharide induce resistance to lethal pneumococcal challenge: roles of T cells and B cells.

    Directory of Open Access Journals (Sweden)

    Noam Cohen

    Full Text Available Mice are exceedingly sensitive to intra-peritoneal (IP challenge with some virulent pneumococci (LD50 = 1 bacterium. To investigate how peripheral contact with bacterial capsular polysaccharide (PS antigen can induce resistance, we pulsed bone marrow dendritic cells (BMDC of C57BL/6 mice with type 4 or type 3 PS, injected the BMDC intra-foot pad (IFP and challenged the mice IP with supra-lethal doses of pneumococci. We examined the responses of T cells and B cells in the draining popliteal lymph node and measured the effects on the bacteria in the peritoneum and blood. We now report that: 1 The PS co-localized with MHC molecules on the BMDC surface; 2 PS-specific T and B cell proliferation and IFNγ secretion was detected in the draining popliteal lymph nodes on day 4; 3 Type-specific resistance to lethal IP challenge was manifested only after day 5; 4 Type-specific IgM and IgG antibodies were detected in the sera of only some of the mice, but B cells were essential for resistance; 5 Control mice vaccinated with a single injection of soluble PS did not develop a response in the draining popliteal lymph node and were not protected; 6 Mice injected with unpulsed BMDC also did not resist challenge: In unprotected mice, pneumococci entered the blood shortly after IP inoculation and multiplied exponentially in both blood and peritoneum killing the mice within 20 hours. Mice vaccinated with PS-pulsed BMDC trapped the bacteria in the peritoneum. The trapped bacteria proliferated exponentially IP, but died suddenly at 18-20 hours. Thus, a single injection of PS antigen associated with intact BMDC is a more effective vaccine than the soluble PS alone. This model system provides a platform for studying novel aspects of PS-targeted vaccination.

  14. Mouse dendritic cells pulsed with capsular polysaccharide induce resistance to lethal pneumococcal challenge: roles of T cells and B cells.

    Science.gov (United States)

    Cohen, Noam; Margalit, Raanan; Pevsner-Fischer, Meirav; Yona, Simon; Jung, Steffen; Eisenbach, Lea; Cohen, Irun R

    2012-01-01

    Mice are exceedingly sensitive to intra-peritoneal (IP) challenge with some virulent pneumococci (LD50 = 1 bacterium). To investigate how peripheral contact with bacterial capsular polysaccharide (PS) antigen can induce resistance, we pulsed bone marrow dendritic cells (BMDC) of C57BL/6 mice with type 4 or type 3 PS, injected the BMDC intra-foot pad (IFP) and challenged the mice IP with supra-lethal doses of pneumococci. We examined the responses of T cells and B cells in the draining popliteal lymph node and measured the effects on the bacteria in the peritoneum and blood. We now report that: 1) The PS co-localized with MHC molecules on the BMDC surface; 2) PS-specific T and B cell proliferation and IFNγ secretion was detected in the draining popliteal lymph nodes on day 4; 3) Type-specific resistance to lethal IP challenge was manifested only after day 5; 4) Type-specific IgM and IgG antibodies were detected in the sera of only some of the mice, but B cells were essential for resistance; 5) Control mice vaccinated with a single injection of soluble PS did not develop a response in the draining popliteal lymph node and were not protected; 6) Mice injected with unpulsed BMDC also did not resist challenge: In unprotected mice, pneumococci entered the blood shortly after IP inoculation and multiplied exponentially in both blood and peritoneum killing the mice within 20 hours. Mice vaccinated with PS-pulsed BMDC trapped the bacteria in the peritoneum. The trapped bacteria proliferated exponentially IP, but died suddenly at 18-20 hours. Thus, a single injection of PS antigen associated with intact BMDC is a more effective vaccine than the soluble PS alone. This model system provides a platform for studying novel aspects of PS-targeted vaccination.

  15. Immune-Complexed Adenovirus Induce AIM2-Mediated Pyroptosis in Human Dendritic Cells

    Science.gov (United States)

    Eichholz, Karsten; Bru, Thierry; Tran, Thi Thu Phuong; Fernandes, Paulo; Mennechet, Franck J. D.; Manel, Nicolas; Alves, Paula; Perreau, Matthieu

    2016-01-01

    Human adenoviruses (HAdVs) are nonenveloped proteinaceous particles containing a linear double-stranded DNA genome. HAdVs cause a spectrum of pathologies in all populations regardless of health standards. Following repeat exposure to multiple HAdV types, we develop robust and long-lived humoral and cellular immune responses that provide life-long protection from de novo infections and persistent HAdV. How HAdVs, anti-HAdV antibodies and antigen presenting cells (APCs) interact to influence infection is still incompletely understood. In our study, we used physical, pharmacological, biochemical, fluorescence and electron microscopy, molecular and cell biology approaches to dissect the impact of immune-complexed HAdV (IC-HAdV) on human monocyte-derived dendritic cells (MoDCs). We show that IC-HAdV generate stabilized complexes of ~200 nm that are efficiently internalized by, and aggregate in, MoDCs. By comparing IC-HAdV, IC-empty capsid, IC-Ad2ts1 (a HAdV-C2 impaired in endosomal escape due to a mutation that impacts protease encapsidation) and IC-AdL40Q (a HAdV-C5 impaired in endosomal escape due to a mutation in protein VI), we demonstrate that protein VI-dependent endosomal escape is required for the HAdV genome to engage the DNA pattern recognition receptor AIM2 (absent in melanoma 2). AIM2 engagement induces pyroptotic MoDC death via ASC (apoptosis-associated speck protein containing a caspase activation/recruitment domain) aggregation, inflammasome formation, caspase 1 activation, and IL-1β and gasdermin D (GSDMD) cleavage. Our study provides mechanistic insight into how humoral immunity initiates an innate immune response to HAdV-C5 in human professional APCs. PMID:27636895

  16. Unconventional maturation of dendritic cells induced by particles from the laminated layer of larval Echinococcus granulosus.

    Science.gov (United States)

    Casaravilla, Cecilia; Pittini, Alvaro; Rückerl, Dominik; Seoane, Paula I; Jenkins, Stephen J; MacDonald, Andrew S; Ferreira, Ana M; Allen, Judith E; Díaz, Alvaro

    2014-08-01

    The larval stage of the cestode parasite Echinococcus granulosus causes hydatid disease in humans and livestock. This infection is characterized by the growth in internal organ parenchymae of fluid-filled structures (hydatids) that elicit surprisingly little inflammation in spite of their massive size and persistence. Hydatids are protected by a millimeter-thick layer of mucin-based extracellular matrix, termed the laminated layer (LL), which is thought to be a major factor determining the host response to the infection. Host cells can interact both with the LL surface and with materials that are shed from it to allow parasite growth. In this work, we analyzed the response of dendritic cells (DCs) to microscopic pieces of the native mucin-based gel of the LL (pLL). In vitro, this material induced an unusual activation state characterized by upregulation of CD86 without concomitant upregulation of CD40 or secretion of cytokines (interleukin 12 [IL-12], IL-10, tumor necrosis factor alpha [TNF-α], and IL-6). When added to Toll-like receptor (TLR) agonists, pLL-potentiated CD86 upregulation and IL-10 secretion while inhibiting CD40 upregulation and IL-12 secretion. In vivo, pLL also caused upregulation of CD86 and inhibited CD40 upregulation in DCs. Contrary to expectations, oxidation of the mucin glycans in pLL with periodate did not abrogate the effects on cells. Reduction of disulfide bonds, which are known to be important for LL structure, strongly diminished the impact of pLL on DCs without altering the particulate nature of the material. In summary, DCs respond to the LL mucin meshwork with a "semimature" activation phenotype, both in vitro and in vivo.

  17. Evidence for lipopolysaccharide-induced differentiation of RAW264⋅ 7 murine macrophage cell line into dendritic like cells

    Indian Academy of Sciences (India)

    Rajiv K Saxena; Val Vallyathan; Daniel M Lewis

    2003-02-01

    Effect of lipopolysaccharide (LPS) on RAW264.7 macrophage cell line was studied. LPS-treated RAW264.7 cells increased in cell size and acquired distinct dendritic morphology. At the optimal dose of LPS (1 g/ml), almost 70% RAW264.7 cells acquired dendritic morphology. Flow cytometric studies indicate that the cell surface markers known to be expressed on dendritic cells and involved in antigen presentation and T cell activation (B7.1, B7.2, CD40, MHC class II antigens and CD1d) were also markedly upregulated on LPS-treated RAW264.7 cells. Our results suggest the possibility that LPS by itself could constitute a sufficient signal for differentiation of macrophages into DC-like cells.

  18. [Dendritic cells (DC) induced from acute myeloid leukemia (AML) cells with cytokine cocktails].

    Science.gov (United States)

    Yan, Kuang-hua; You, Sheng-guo; Bian, Shou-geng; Ma, Guan-jie; Ge, Wei; Ma, Shuang; Liu, Shi-he; Zhao, Chun-hua

    2003-07-01

    To explore the feasibility of DC being in vitro induced from AML cells with cytokine cocktails and their biological properties. AML cells were cultured in either presence or absence of cytokine cocktails. DC were studied for morphology, and cytochemical and immunofluorescent staining. Functions of DC were examined by MLC, FITC-conjugated dextran uptake test, and LDH release assay. RT-PCR and FISH were used to analyze the specific fusion genes of culture-derived DC. Classical DC morphological changes occurred in all 15 cultured AML cells. DC-associated surface molecules such as CD(1a), CD(80), CD(86), CD(106), CD(83) and HLA-DR were upregulated (P AML cells uncultured or cultured in the absence of cytokines (P CTL assay was performed in 5 of the 15 samples. At effector/target ratio of 20:1, auto-T lymphocytes primed with the culture-derived DC exhibited no more killing activity to auto-AML cells than those stimulated by IL-2 or uncultured AML cells. Culture-derived DC presenced the native AML-specific aberrant karyotype and related fusion gene. Cytokine cocktails could in vitro induce AML cells into DC with classical morphology, immunophenotype and function. DC maturity induced by different cytokine cocktails could be variable. Culture-derived DC were originated from the native AML cells. AML cells could make the auto-T lymphocyte anergy.

  19. Leukemia-specific T-cell reactivity induced by leukemic dendritic cells is augmented by 4-1BB targeting.

    Science.gov (United States)

    Houtenbos, Ilse; Westers, Theresia M; Dijkhuis, Annemiek; de Gruijl, Tanja D; Ossenkoppele, Gert J; van de Loosdrecht, Arjan A

    2007-01-01

    Acute myelogenous leukemia (AML) blasts are able to differentiate into leukemia-derived dendritic cells (AML-DC), thereby enabling efficient presentation of known and unknown leukemic antigens. Advances in culture techniques and AML-DC characterization justify clinical application. However, additional measures are likely needed to potentiate vaccines and overcome the intrinsic tolerant state of the patients' immune system. Engagement of the costimulatory molecule 4-1BB can break immunologic tolerance and increase CTL responses. In this study, we examined the role of the 4-1BB ligand (4-1BBL) on T-cell responses induced by AML-DC. In allogeneic and autologous cocultures of T cells and AML-DC, the effect of the addition of 4-1BBL on T-cell proliferation, T-cell subpopulations, and T-cell function was determined. Addition of 4-1BBL to cocultures of AML-DC and T cells induced a preferential increase in the proliferation of CD8(+) T cells. Increased differentiation into effector and central memory populations was observed in both CD4(+) and CD8(+) T cells in the presence of 4-1BBL. AML-DC induce a T helper 1 response, characterized by high IFN-gamma production, which is significantly increased by targeting 4-1BB. T cells primed in the presence of 4-1BBL show specificity for the leukemia-associated antigen Wilms' tumor 1, whereas cytotoxicity assays with leukemic blast targets showed the cytolytic potential of T cells primed in the presence of 4-1BBL. We conclude that 4-1BBL is an effective adjuvant to enhance T-cell responses elicited by AML-DC.

  20. Clinical efficacy of immunotherapy of dendritic cell and cytokine-induced killer cell combined with chemotherapy for treatment of multiple myeloma

    Institute of Scientific and Technical Information of China (English)

    钟国成

    2013-01-01

    Objective This research was aimed to evaluate the immune mechanism and clinical effect of immunotherapy of dendritic cells(DC) and cytokine-induced killer cell(CIK) combined with chemotherapy on multiple myeloma(MM). Methods 60 patients with MM were randomly

  1. CD8α− Dendritic Cells Induce Antigen-Specific T Follicular Helper Cells Generating Efficient Humoral Immune Responses

    Directory of Open Access Journals (Sweden)

    Changsik Shin

    2015-06-01

    Full Text Available Recent studies on T follicular helper (Tfh cells have significantly advanced our understanding of T cell-dependent B cell responses. However, little is known about the early stage of Tfh cell commitment by dendritic cells (DCs, particularly by the conventional CD8α+ and CD8α− DC subsets. We show that CD8α− DCs localized at the interfollicular zone play a pivotal role in the induction of antigen-specific Tfh cells by upregulating the expression of Icosl and Ox40l through the non-canonical NF-κB signaling pathway. Tfh cells induced by CD8α− DCs function as true B cell helpers, resulting in significantly increased humoral immune responses against various human pathogenic antigens, including Yersinia pestis LcrV, HIV Gag, and hepatitis B surface antigen. Our findings uncover a mechanistic role of CD8α− DCs in the initiation of Tfh cell differentiation and thereby provide a rationale for investigating CD8α− DCs in enhancing antigen-specific humoral immune responses for improving vaccines and therapeutics.

  2. Nanoparticles modify dendritic cell homeostasis and induce non-specific effects on immunity to malaria.

    Science.gov (United States)

    Xiang, Sue D; Kong, Ying Y; Hanley, Jennifer; Fuchsberger, Martina; Crimeen-Irwin, Blessing; Plebanski, Magdalena

    2015-01-01

    Many current vaccines to a specific pathogen influence responses to other pathogens in a process called heterologous immunity. We propose that their particulate nature contributes to non-specific effects. Herein, we demonstrate polystyrene nanoparticles modulate dendritic cell (DC) homeostasis, thereby promoting a persistent enhanced state of immune readiness to a subsequent infectious challenge. Particles (approximately 40 nm and 500 nm carboxylated polystyrene nanoparticles; PSNPs) alone or conjugated to a model antigen were injected in mice, and DCs in draining lymph nodes (dLNs) and bone-marrow (BM) quantified by flow cytometry. BM cells were tested for capacity to generate DCs upon culture with granulocyte and macrophage colony stimulating factor. Mice were challenged with Plasmodium yoelli. Blood parasitaemias were monitored by GIEMSA. Sera was analyzed for antibodies by ELISA. Intradermal administration of 40 nm PSNPs induced anti-inflammatory cytokines, chemokines and growth factors, increased numbers and proportions of DCs in the dLN, and increased the capacity of BM to generate DCs. Consistent with these unexpected changes, 40 nm PSNPs pre-injected mice had enhanced ability to generate immunity to a subsequent malarial infection. Intradermal administration of 40 nm PSNPs modifies DC homeostasis, which may at least in part explain the observed beneficial heterologous effects of current particulate vaccines. Further nanotechnological developments may exploit such strategies to promote beneficial non-specific effects. © The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  3. Matrine derivate MASM suppresses LPS-induced phenotypic and functional maturation of murine bone marrow-derived dendritic cells.

    Science.gov (United States)

    Xu, Jing; Qi, Yang; Xu, Wei-Heng; Liu, Ying; Qiu, Lie; Wang, Ke-Qi; Hu, Hong-Gang; He, Zhi-Gao; Zhang, Jun-Ping

    2016-07-01

    Dendritic cell (DC) maturation process is a crucial step for the development of T cell immune responses and immune tolerance. In this study, we evaluated MASM, a novel derivative of the natural compound matrine that possesses a significant anti-inflammatory and immune-regulating property, for its efficacy to inhibit lipopolysaccharides (LPS)-induced maturation of murine bone marrow-derived dendritic cells. Here we show that MASM profoundly suppresses LPS-induced phenotypic and functional DC maturation. MASM inhibited LPS-induced expression of costimulatory molecules CD80 and CD86 in a concentration-dependent manner. MASM also attenuated LPS-induced IL-12p70, TNF-α, IL-6 and NO release of DCs. The MASM-treated DCs were highly efficient at antigen capture via mannose receptor-mediated endocytosis but showed weak stimulatory capacity for allogeneic T cell proliferation. Furthermore, MASM inhibited LPS-induced PI3K/Akt, MAPK and NF-κB pathways. These novel findings provide new insight into the immunopharmacological role of MASM in impacting on the DCs.

  4. EWS/FLI-l peptide-pulsed dendritic cells induces the antitumor immunity in a murine Ewing's sarcoma cell model.

    Science.gov (United States)

    Peng, Wei; Huang, Xunwu; Yang, Dazhi

    2014-08-01

    An increasing number of T-cell epitopes derived from various tumor-associated antigens have been reported, and they proved to play significant roles for tumor rejection both in vivo and in vitro. Over 85% of Ewing's sarcoma family of tumors (ESFTs) express tumor-specific chimeric protein EWS/FLI-1, making it an attractive target for therapeutic cytotoxic T-lymphocyte responses. Here, we identified a novel peptide epitope derived from the EWS/FLI-1 protein and demonstrated that effectors induced by the peptide could specifically secrete IFN-γ and lyse the tumor cell line of EWS/FLI-1-positive and HLA-matched cells. In addition, mice treated with dendritic cells pulsed with the EWS/FLI-1 epitope were able to reject a lethal tumor inoculation of the Ewing's sarcoma A673 cells. Therefore, these data provide evidence for the use of the EWS/FLI-l peptide epitope in T cell-based immunotherapeutic concepts against Ewing's sarcoma cell in vitro and in vivo.

  5. A role for tolerogenic dendritic cell-induced B-regulatory cells in type 1 diabetes mellitus.

    Science.gov (United States)

    Giannoukakis, Nick; Trucco, Massimo

    2012-08-01

    To review the important recent findings on the nature, characteristics and function of novel populations of immunosuppressive B-lymphocytes (Bregs) and their possible role as a regulatory cell population, potentially responsive to dendritic cells, in preventing and possibly controlling type 1 diabetes mellitus. Although almost all of the experimental work in immunosuppressive B-lymphocyte biology has focused on their role in arthritis and experimental inflammatory bowel disease, only recently has a role for Bregs in the regulation of type 1 diabetes been looked at more extensively. IL-10-producing Bregs are of significant interest, more so because of their potential modulation by tolerogenic dendritic cells. Additionally, novel populations have been discovered that could also be relevant in the regulation of diabetes autoimmunity. The unexpected discovery of a novel population of Bregs, whose frequency was upregulated in our phase I clinical trial of tolerogenic autologous dendritic cell administration in humans, opens a new frontier for basic and translational research into these novel cell populations. Bregs are a recently rediscovered population of suppressive lymphocytes whose activation, differentiation and function could be sensitive to tolerogenic dendritic cell networks. Modulation of these dendritic cell networks, or the Bregs directly, offers novel options to attenuate and reverse type 1 diabetes autoimmunity as a possible cure for the disease.

  6. Ganoderma lucidum polysaccharides can induce human monocytic leukemia cells into dendritic cells with immuno-stimulatory function

    Directory of Open Access Journals (Sweden)

    Lau Yu

    2008-07-01

    Full Text Available Abstract Background Previous studies demonstrated Ganoderma lucidum polysaccharides (GL-PS, a form of bioactive β-glucan can stimulate the maturation of monocyte-derived dendritic cells (DC. The question of how leukemic cells especially in monocytic lineage respond to GL-PS stimuli remains unclear. Results In this study, we used in vitro culture model with leukemic monocytic cell-lines THP-1 and U937 as monocytic effectors cells for proliferation responses and DCs induction. We treated the THP-1 and U937 cells with purified GL-PS (100 μg/mL or GL-PS with GM-CSF/IL-4. GL-PS alone induced proliferative response on both THP-1 and U937 cells but only THP-1 transformed into typical DC morphology when stimulated with GL-PS plus GM-CSF/IL-4. The transformed THP-1 DCs had significant increase expression of HLA-DR, CD40, CD80 and CD86 though not as high as the extent of normal monocyte-derived DCs. They had similar antigen-uptake ability as the normal monocyte-derived DCs positive control. However, their potency in inducing allogeneic T cell proliferation was also less than that of normal monocyte-derived DCs. Conclusion Our findings suggested that GL-PS could induce selected monocytic leukemic cell differentiation into DCs with immuno-stimulatory function. The possible clinical impact of using this commonly used medicinal mushroom in patients with monocytic leukemia (AML-M4 and M5 deserved further investigation.

  7. Lactobacillus acidophilus induces virus immune defence genes in murine dendritic cells by a Toll-like receptor-2-dependent mechanism

    DEFF Research Database (Denmark)

    Weiss, Gudrun Margarethe; Rasmussen, Simon; Hjerrild Zeuthen, L.

    2010-01-01

    -regulation of type I interferons (IFNs), we hypothesized that the strong IL-12-inducing capacity of Lactobacillus acidophilus NCFM in murine bone-marrow-derived dendritic cells (DCs) is caused by an up-regulation of IFN-beta, which subsequently induces IL-12 and the double-stranded RNA binding Toll-like receptor-3......-12 and Tlr-3 in DCs stimulated with L. acidophilus NCFM. Collectively, our results reveal that certain lactobacilli trigger the expression of viral defence genes in DCs in a TLR-2 manner dependent on IFN-beta....

  8. Gene Transfer to Dendritic Cells Induced a Protective Immunity against Melanoma

    Institute of Scientific and Technical Information of China (English)

    Pat Metharom; Kay A.O. Ellem; Ming Q. Wei

    2005-01-01

    Lentiviral vectors have shown promises for efficient gene transfer to dividing as well as nondividing cells. In this study, we explored lentiviral vector-mediated, the entire mTRP-2 gene transfer and expression in dendritic cells (DCs). Adoptive transfer of DCs-expressing mTRP-2 (DC-HR'CmT2) into C57BL/6 mouse was also assessed.Dendritic cells were harvested from bone marrow and functional DCs were proved by allogeneic mixed lymphocyte reaction. Lentiviral vectors were produced by transient transfection of 293T cells. Transduction of DCs was proved by marker gene expression and PCR and RT-PCR amplification. Implantation of the transduced DCs, depletion of immune cells as well as the survival of the mice after tumour challenge were investigated. High efficiency of gene transfer into mature DCs was achieved. The high level expression of the functional antigen (TRP-2) and induction of protective immunity by adoptive transfer of TRP-2 gene modified DCs were demonstrated. In vivo study showed a complete protection of mice from further melanoma cell challenge. In comparison, only 83% of mice survived when mTRP-2 peptide-pulsed DCs were administered, suggesting the generation of specific protection. Together, these results demonstrated the usefulness of this gene transfer to DC approach for immunotherapy of cancer and indicated that using tumour associated antigens (TAAs) for gene transfer may be potentially beneficial for the therapy of melanoma.

  9. Lentivirus-Induced Dendritic Cells (iDC for Immune-Regenerative Therapies in Cancer and Stem Cell Transplantation

    Directory of Open Access Journals (Sweden)

    Renata Stripecke

    2014-08-01

    Full Text Available Conventional dendritic cells (cDC are ex vivo differentiated professional antigen presenting cells capable of potently stimulating naïve T cells and with vast potential for immunotherapeutic applications. The manufacture of clinical-grade cDC is relatively complex and requires several days for completion. Clinical trials showed poor trafficking of cDC from subcutaneous injection sites to lymph nodes (LN, where DC can optimally stimulate naïve lymphocytes for long-lasting memory responses. We demonstrated in mouse and human systems that a single overnight ex vivo lentiviral (LV gene transfer into DC precursors for production of combination of cytokines and antigens was capable to induce autonomous self-differentiation of antigen-loaded DC in vitro and in vivo. These highly viable induced DC (iDC effectively migrated from the injected skin to LN, where they effectively activated de novo antigen-specific effector memory T cells. Two iDC modalities were validated in relevant animal models and are now in clinical development: Self-differentiated Myeloid-derived Antigen-presenting-cells Reactive against Tumors co-expressing GM-CSF/IL-4/TRP2 for melanoma immunotherapy in the autologous setting (SmartDCtrp2, and Self-differentiated Myeloid-derived Lentivirus-induced against human cytomegalovirus as an allogeneic matched adoptive cell after stem cell transplantation (SmyleDCpp65. The lentiviral vector design and packaging methodology has “evolved” continuously in order to simplify and optimize function and biosafety of in vitro and in vivo genetic reprogramming of iDC. Here, we address the challenges seeking for new creations of genetically programmed iDC and integrase-defective LV vaccines for immune regeneration.

  10. Nanoencapsulated budesonide in self-stratified polyurethane-polyurea nanoparticles is highly effective in inducing human tolerogenic dendritic cells.

    Science.gov (United States)

    Flórez-Grau, Georgina; Rocas, Pau; Cabezón, Raquel; España, Carolina; Panés, Julián; Rocas, Josep; Albericio, Fernando; Benítez-Ribas, Daniel

    2016-09-25

    The design of innovative strategies to selectively target cells, such antigen-presenting cells and dendritic cells, in vivo to induce immune tolerance is gaining interest and relevance for the treatment of immune-mediated diseases. A novel loaded-nanosystem strategy to generate tolerogenic dendritic cells (tol-DCs) was evaluated. Hence budesonide (BDS) was encapsulated in multiwalled polyurethane-polyurea nanoparticles (PUUa NPs-BDS) based on self-stratified polymers by hydrophobic interactions at the oil-water interface. DCs treated with encapsulated BDS presented a prominent downregulation of costimulatory molecules (CD80, CD83 and MHCII) and upregulation of inhibitory receptors. Moreover, DCs treated with these PUUa NPs-BDS also secreted large amounts of IL-10, a crucial anti-inflammatory cytokine to induce tolerance, and inhibited T lymphocyte activation in a specific manner compared to those cells generated with free BDS. These results demonstrate that PUUa NPs-BDS are a highly specific and efficient system through which to induce DCs with a tolerogenic profile. Given the capacity of PUUa NPs-BDS, this delivery system has a clear advantage for translation to in vivo studies.

  11. Tumor cells prevent mouse dendritic cell maturation induced by TLR ligands.

    Science.gov (United States)

    Idoyaga, Juliana; Moreno, José; Bonifaz, Laura

    2007-08-01

    Tumor cells can evade the immune system through several mechanisms, one of which is to block DC maturation. It has been suggested that signaling via Toll-like receptors (TLR) may be involved in the induction of prophylactic anti-cancer immunity and in the treatment of established tumors. In the present study we found that high numbers of tumor cells interfere with BMDC activation induced by the TLR ligands LPS and poly IC. Tumor cells blocked TLR3- and TLR4-mediated induction of MHCII and the co-stimulatory molecules CD40 and CD86, as well as the cytokines IL-12, TNF-alpha and IL-6. Importantly, tumor cells induced inhibitory molecules (B7-DC, B7-H1 and CD80) on spleen DC in vivo and on BMDC, even in the presence of TLR ligands. Moreover, after a long exposure with tumor cells, purified BMDC were unable to respond to a second challenge with TLR ligands. The failure of tumor exposed-BMDC to express co-stimulatory molecules and cytokines in the presence of TLR ligands has implications for the future development of DC-based cancer immune therapies using TLR ligands as adjuvants for the activation of DC.

  12. SLAM/SLAM interactions inhibit CD40-induced production of inflammatory cytokines in monocyte-derived dendritic cells.

    Science.gov (United States)

    Réthi, Bence; Gogolák, Péter; Szatmari, Istvan; Veres, Agota; Erdôs, Erika; Nagy, Laszlo; Rajnavölgyi, Eva; Terhorst, Cox; Lányi, Arpád

    2006-04-01

    Signaling lymphocyte activation molecule (SLAM, CD150, or SLAMF1) is a self-ligand receptor on the surface of activated T- and B-lymphocytes, macrophages, and dendritic cells (DCs). Here we examine the effect of SLAM/SLAM interactions on CD40L-induced CD40 signaling pathways in human DCs. CD40L-expressing L929 cells induced DCs to produce interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), and IL-12, which was strongly inhibited by coexpression of SLAM on the surface of the L929 cells. Similarly, transfection of DCs with SLAM strongly reduced CD40L-induced IL-12 production. Furthermore, the negative effect of SLAM/SLAM interactions on CD40L-induced DC activation was also detected in the presence of lipopolysaccharide (LPS). LPS-induced IL-12 secretion, however, was not inhibited by SLAM engagement. CD40L-activated DCs affected by exposure to SLAM/SLAM engagement were impaired in their ability to induce differentiation of naive T lymphocytes into interferon-gamma (IFN-gamma)-producing T-helper 1 (Th1) effector cells. These inhibitory effects were not the result of a general unresponsiveness of DCs to CD40L, as SLAM/SLAM interactions did not prevent CD40L-induced up-regulation of CD83, CD86, or human leukocyte antigen (HLA)-DQ on the surface of DCs. Taken together, the results indicate that SLAM/SLAM interactions inhibit CD40-induced signal transduction in monocyte-derived dendritic cells, an effect that was not detectable in earlier studies using anti-SLAM monoclonal antibodies.

  13. Melanoma cell lysate induces CCR7 expression and in vivo migration to draining lymph nodes of therapeutic human dendritic cells.

    Science.gov (United States)

    González, Fermín E; Ortiz, Carolina; Reyes, Montserrat; Dutzan, Nicolás; Patel, Vyomesh; Pereda, Cristián; Gleisner, Maria A; López, Mercedes N; Gutkind, J Silvio; Salazar-Onfray, Flavio

    2014-07-01

    We have previously reported a novel method for the production of tumour-antigen-presenting cells (referred to as TAPCells) that are currently being used in cancer therapy, using an allogeneic melanoma-derived cell lysate (referred to as TRIMEL) as an antigen provider and activation factor. It was recently demonstrated that TAPCell-based immunotherapy induces T-cell-mediated immune responses resulting in improved long-term survival of stage IV melanoma patients. Clinically, dendritic cell (DC) migration from injected sites to lymph nodes is an important requirement for an effective anti-tumour immunization. This mobilization of DCs is mainly driven by the C-C chemokine receptor type 7 (CCR7), which is up-regulated on mature DCs. Using flow cytometry and immunohistochemistry, we investigated if TRIMEL was capable of inducing the expression of the CCR7 on TAPCells and enhancing their migration in vitro, as well as their in vivo relocation to lymph nodes in an ectopic xenograft animal model. Our results confirmed that TRIMEL induces a phenotypic maturation and increases the expression of surface CCR7 on melanoma patient-derived DCs, and also on the monocytic/macrophage cell line THP-1. Moreover, in vitro assays showed that TRIMEL-stimulated DCs and THP-1 cells were capable of migrating specifically in the presence of the CCR7 ligand CCL19. Finally, we demonstrated that TAPCells could migrate in vivo from the injection site into the draining lymph nodes. This work contributes to an increased understanding of the biology of DCs produced ex vivo allowing the design of new strategies for effective DC-based vaccines for treating aggressive melanomas.

  14. Collagen I-induced dendritic cells activation is regulated by TNF- production through down-regulation of IRF4

    Indian Academy of Sciences (India)

    Barun Poudel; Hyeon-Hui Ki; Young-Mi Lee; Dae-Ki Kim

    2015-03-01

    Previously we have shown that collagen I enhances the maturation and function of dendritic cells (DCs). Inflammatory mediators such as tumour necrosis factor (TNF)-, interleukin (IL)-1 and lipopolysaccharide (LPS) are also known to activate DCs. Here we investigated the involvement of TNF- on the collagen I-induced DCs activation. TNF-a neutralization inhibited collagen I-induced IL-12 secretions by DCs. Additionally, we observed suppression of collagen I-induced costimulatory molecules expression along with down-regulation of genes involved in DCs activation pathway. Furthermore, TNF- inhibition upon collagen Istimulation up-regulated the expression of interferon regulatory transcription factor IRF4, when compared to collagen I only treated cells. Collectively, our data demonstrate that collagen I induce TNF- production, which is crucial for the activation and function of DCs, through down-regulation of IRF4, and implicates the importance in development of anti- TNF- therapeutics for several inflammatory diseases.

  15. Herpes simplex virus type 2 induces rapid cell death and functional impairment of murine dendritic cells in vitro

    NARCIS (Netherlands)

    Jones, CA; Fernandez, M; Herc, K; Bosnjak, L; Miranda-Saksena, M; Boadle, RA; Cunningham, A

    2003-01-01

    Dendritic cells (DC) are critical for stimulation of naive T cells. Little is known about the effect of herpes simplex virus type 2 (HSV-2) infection on DC structure or function or if the observed effects of HSV-1 on human DC are reproduced in murine DC. Here, we demonstrate that by 12 h

  16. Interferon-γ Added During Bacillus Calmette-Guerin Induced Dendritic Cell Maturation Stimulates Potent Th1 Immune Responses

    Directory of Open Access Journals (Sweden)

    Pestano Linda A

    2003-10-01

    Full Text Available Abstract Dendritic cells (DC are increasingly prepared in vitro for use in immunotherapy trials. Mature DC express high levels of surface molecules needed for T cell activation and are superior at antigen-presentation than immature DC. Bacillus Calmette-Guerin (BCG is one of several products known to induce DC maturation, and interferon (IFN-γ has been shown to enhance the activity of DC stimulated with certain maturation factors. In this study, we investigated the use of IFN-γ in combination with the powerful maturation agent, BCG. The treatment of immature DC with IFN-γ plus BCG led to the upregulation of CD54, CD80, and CD86 in comparison with BCG treatment alone. In MLR or recall immune responses, the addition of IFN-γ at the time of BCG-treatment did not increase the number of antigen-specific T cells but enhanced the development of IFN-γ-producing Th1 cells. In primary immune responses, on the other hand, BCG and IFN-γ co-treated DC stimulated higher proportions of specific T cells as well as IFN-γ secretion by these T cells. Thus the use of IFN-γ during BCG-induced DC maturation differentially affects the nature of recall versus naïve antigen-specific T-cell responses. IFN-γ co-treatment with BCG was found to induce IL-12 and, in some instances, inhibit IL-10 secretion by DC. These findings greatly enhance the potential of BCG-matured dendritic cells for use in cancer immunotherapy.

  17. Divergent Effects of Dendritic Cells on Pancreatitis

    Science.gov (United States)

    2015-09-01

    cells, Gr1+ inflammatory monocytes and neutrophils, or TNF production were induced to develop chronic pancreatitis in the context of DC overexpansion...Z. Yao, W. Cao, and Y.J. Liu. 2005. TSLP-activated dendritic cells induce an inflammatory T helper type 2 cell response through OX40 ligand. J. Exp...Public reporting burden for this collection of information is estimated to average 1 hour per response , including the time for reviewing instructions

  18. Dendritic Cells Stimulated by Cationic Liposomes.

    Science.gov (United States)

    Vitor, Micaela Tamara; Bergami-Santos, Patrícia Cruz; Cruz, Karen Steponavicius Piedade; Pinho, Mariana Pereira; Barbuto, José Alexandre Marzagão; De La Torre, Lucimara Gaziola

    2016-01-01

    Immunotherapy of cancer aims to harness the immune system to detect and destroy cancer cells. To induce an immune response against cancer, activated dendritic cells (DCs) must present tumor antigens to T lymphocytes of patients. However, cancer patients' DCs are frequently defective, therefore, they are prone to induce rather tolerance than immune responses. In this context, loading tumor antigens into DCs and, at the same time, activating these cells, is a tempting goal within the field. Thus, we investigated the effects of cationic liposomes on the DCs differentiation/maturation, evaluating their surface phenotype and ability to stimulate T lymphocytes proliferation in vitro. The cationic liposomes composed by egg phosphatidylcholine, 1,2-dioleoyl-3-trimethylammonium propane and 1,2-dioleoylphosphatidylethanolamine (50/25/25% molar) were prepared by the thin film method followed by extrusion (65 nm, polydispersity of 0.13) and by the dehydration-rehydration method (95% of the population 107 nm, polydispersity of 0.52). The phenotypic analysis of dendritic cells and the analysis of T lymphocyte proliferation were performed by flow cytometry and showed that both cationic liposomes were incorporated and activated dendritic cells. Extruded liposomes were better incorporated and induced higher CD86 expression for dendritic cells than dehydrated-rehydrated vesicles. Furthermore, dendritic cells which internalized extruded liposomes also provided stronger T lymphocyte stimulation. Thus, cationic liposomes with a smaller size and polydispersity seem to be better incorporated by dendritic cells. Hence, these cationic liposomes could be used as a potential tool in further cancer immunotherapy strategies and contribute to new strategies in immunotherapy.

  19. Cytokine-induced killer cells/dendritic cells and cytokine-induced killer cells immunotherapy for the treatment of esophageal cancer in China: a meta-analysis

    Science.gov (United States)

    Liu, Yan; Mu, Ying; Zhang, Anqi; Ren, Shaoda; Wang, Weihua; Xie, Jiaping; Zhang, Yingxin; Zhou, Changhui

    2017-01-01

    Background Immunotherapy based on cytokine-induced killer cells or combination of dendritic cells and cytokine-induced killer cells (CIK/DC-CIK) showed promising clinical outcomes for treating esophageal cancer (EC). However, the clinical benefit varies among previous studies. Therefore, it is necessary to systematically evaluate the curative efficacy and safety of CIK/DC-CIK immunotherapy as an adjuvant therapy for conventional therapeutic strategies in the treatment of EC. Materials and methods Clinical trials published before October 2016 and reporting CIK/DC-CIK immunotherapy treatment responses or safety for EC were searched in Cochrane Library, EMBASE, PubMed, Wanfang and China National Knowledge Internet databases. Research quality and heterogeneity were evaluated before analysis, and pooled analyses were performed using random- or fixed-effect models. Results This research covered 11 trials including 994 EC patients. Results of this meta-analysis indicated that compared with conventional therapy, the combination of conventional therapy with CIK/DC-CIK immunotherapy significantly prolonged the 1-year overall survival (OS) rate, overall response rate (ORR) and disease control rate (DCR) (1-year OS: P=0.0005; ORR and DCR: Pimmunotherapy, lymphocyte percentages of CD3+ and CD3−CD56+ subsets (P0.05). Conclusion The combination of CIK/DC-CIK immunotherapy and conventional therapy is safe and markedly prolongs survival time, enhances immune function and improves the treatment efficacy for EC.

  20. Curative Effects of Dendritic Cells Combined with Cytokine-Induced Killer Cells in Patients with Malignant Pericardial Effusion

    Science.gov (United States)

    Wang, Hongmin; Cui, Yuzhong; Wang, Sheng; Zhao, Rusen; Sun, Ming

    2016-01-01

    Background To determine the effects of dendritic cells (DCs) and cytokine-induced killer (CIK) cells in patients with malignant pericardial effusion. Material/Methods All patients underwent pericardial puncture and indwelling catheter insertion. After pericardial drainage, the 16 patients in the treatment group received an infusion of 20 mL DCs and CIK cells (>1.0×1010 cells) and 500,000 U interleukin (IL)-2 for 3 successive days. The 15 control-group patients received 30 mg/m2 cisplatin and 500,000 U IL-2 for 3 successive days. The treatment effects were assessed using imaging data. Results The total efficiency and complete remission rates were higher in the treatment group than in the control group at 4 weeks (total efficiency: 87.50% vs. 73.33%; complete remission: 62.50% vs. 46.67%) and 3 months after the treatment (total efficiency: 81.25% vs. 66.67%; complete remission: 50.00% vs. 40.00%; P<0.05 for all). In both groups, the Karnofsky scores for quality of life improved after treatment. However, the curative effects were better in the treatment group than in the control group (P<0.05). The following adverse reactions occurred: fever, 6 treatment-group patients and 3 control-group patients; chest pain, 2 treatment-group patients and 7 control-group patients; gastrointestinal reactions, 1 treatment-group patient and 6 control-group patients; and bone marrow suppression, 1 treatment-group patient and 5 control-group patients. The between-group differences in adverse reactions were significant (P<0.05). Conclusions The combination of DCs and CIK cells effectively treated malignant pericardial effusion, produced few side effects, and improved the patients’ quality of life. PMID:27806024

  1. Differential Gene Expression in Thrombomodulin (TM; CD141)+ and TM− Dendritic Cell Subsets

    OpenAIRE

    Masaaki Toda; Zhifei Shao; Yamaguchi, Ken D.; Takehiro Takagi; Corina N D'Alessandro-Gabazza; Osamu Taguchi; Hugh Salamon; Leung, Lawrence L. K.; Gabazza, Esteban C.; John Morser

    2013-01-01

    Previously we have shown in a mouse model of bronchial asthma that thrombomodulin can convert immunogenic conventional dendritic cells into tolerogenic dendritic cells while inducing its own expression on their cell surface. Thrombomodulin(+) dendritic cells are tolerogenic while thrombomodulin(-) dendritic cells are pro-inflammatory and immunogenic. Here we hypothesized that thrombomodulin treatment of dendritic cells would modulate inflammatory gene expression. Murine bone marrow-derived de...

  2. Dendritic cells loaded with pancreatic Cancer Stem Cells (CSCs lysates induce antitumor immune killing effect in vitro.

    Directory of Open Access Journals (Sweden)

    Tao Yin

    Full Text Available According to the cancer stem cells (CSCs theory, malignant tumors may be heterogeneous in which a small population of CSCs drive the progression of cancer. Because of their intrinsic abilities, CSCs may survive a variety of treatments and then lead to therapeutic resistance and cancer recurrence. Pancreatic CSCs have been reported to be responsible for the malignant behaviors of pancreatic cancer, including suppression of immune protection. Thus, development of immune strategies to eradicate pancreatic CSCs may be of great value for the treatment of pancreatic cancer. In this study, we enriched pancreatic CSCs by culturing Panc-1 cells under sphere-forming conditions. Panc-1 CSCs expressed low levels of HLA-ABC and CD86, as measured by flow cytometry analysis. We further found that the Panc-1 CSCs modulate immunity by inhibiting lymphocyte proliferation which is promoted by phytohemagglutinin (PHA and anti-CD3 monoclonal antibodies. The monocyte derived dendritic cells (DCs were charged with total lysates generated from Panc-1 CSCs obtained from tumor sphere culturing. After co-culturing with lymphocytes at different ratios, the Panc-1 CSCs lysates modified DC effectively promoted lymphocyte proliferation. The activating efficiency reached 72.4% and 74.7% at the ratios of 1∶10 and 1∶20 with lymphocytes. The activated lymphocytes secreted high levels of INF-γ and IL-2, which are strong antitumor cytokines. Moreover, Panc-1 CSCs lysates modified DC induced significant cytotoxic effects of lymphocytes on Panc-1 CSCs and parental Panc-1 cells, respectively, as shown by lactate dehydrogenase (LDH assay. Our study demonstrates that the development of CSCs-based vaccine is a promising strategy for treating pancreatic cancer.

  3. Human dendritic cells mediate cellular apoptosis via tumor necrosis factor-related apoptosis-inducing ligand (TRAIL).

    Science.gov (United States)

    Fanger, N A; Maliszewski, C R; Schooley, K; Griffith, T S

    1999-10-18

    TRAIL (TNF-related apoptosis-inducing ligand) is a member of the TNF family that induces apoptosis in a variety of cancer cells. In this study, we demonstrate that human CD11c(+) blood dendritic cells (DCs) express TRAIL after stimulation with either interferon (IFN)-gamma or -alpha and acquire the ability to kill TRAIL-sensitive tumor cell targets but not TRAIL-resistant tumor cells or normal cell types. The DC-mediated apoptosis was TRAIL specific, as soluble TRAIL receptor blocked target cell death. Moreover, IFN-stimulated interleukin (IL)-3 receptor (R)alpha(+) blood precursor (pre-)DCs displayed minimal cytotoxicity toward the same target cells, demonstrating a clear functional difference between the CD11c(+) DC and IL-3Ralpha(+) pre-DC subsets. These results indicate that TRAIL may serve as an innate effector molecule on CD11c(+) DCs for the elimination of spontaneously arising tumor cells and suggest a means by which TRAIL-expressing DCs may regulate or eliminate T cells responding to antigen presented by the DCs.

  4. Cigarette smoke-induced accumulation of lung dendritic cells is interleukin-1α-dependent in mice

    Science.gov (United States)

    2012-01-01

    Background Evidence suggests that dendritic cells accumulate in the lungs of COPD patients and correlate with disease severity. We investigated the importance of IL-1R1 and its ligands IL-1α and β to dendritic cell accumulation and maturation in response to cigarette smoke exposure. Methods Mice were exposed to cigarette smoke using a whole body smoke exposure system. IL-1R1-, TLR4-, and IL-1α-deficient mice, as well as anti-IL-1α and anti-IL-1β blocking antibodies were used to study the importance of IL-1R1 and TLR4 to dendritic cell accumulation and activation. Results Acute and chronic cigarette smoke exposure led to increased frequency of lung dendritic cells. Accumulation and activation of dendritic cells was IL-1R1/IL-1α dependent, but TLR4- and IL-1β-independent. Corroborating the cellular data, expression of CCL20, a potent dendritic cells chemoattractant, was IL-1R1/IL-1α-dependent. Studies using IL-1R1 bone marrow-chimeric mice revealed the importance of IL-1R1 signaling on lung structural cells for CCL20 expression. Consistent with the importance of dendritic cells in T cell activation, we observed decreased CD4+ and CD8+ T cell activation in cigarette smoke-exposed IL-1R1-deficient mice. Conclusion Our findings convey the importance of IL-1R1/IL-1α to the recruitment and activation of dendritic cells in response to cigarette smoke exposure. PMID:22992200

  5. B lymphocytes induce the formation of follicular dendritic cell clusters in a lymphotoxin alpha-dependent fashion.

    Science.gov (United States)

    Fu, Y X; Huang, G; Wang, Y; Chaplin, D D

    1998-04-06

    Lymphotoxin (LT)alpha is expressed by activated T cells, especially CD4(+) T helper type 1 cells, and by activated B and natural killer cells, but the functions of this molecule in vivo are incompletely defined. We have previously shown that follicular dendritic cell (FDC) clusters and germinal centers (GCs) are absent from the peripheral lymphoid tissues of LTalpha-deficient (LTalpha-/-) mice. LTalpha-/- mice produce high levels of antigen-specific immunoglobulin (Ig)M, but very low levels of IgG after immunization with sheep red blood cells. We show here that LTalpha-expressing B cells are essential for the recovery of primary, secondary, and memory humoral immune responses in LTalpha-/- mice. It is not necessary for T cells to express LTalpha to support these immune functions. Importantly, LTalpha-expressing B cells alone are essential and sufficient for the formation of FDC clusters. Once these clusters are formed by LTalpha-expressing B cells, then LTalpha-deficient T cells can interact with B cells to generate GCs and productive class-switched antibody responses. Thus, B cells themselves provide an essential signal that induces and maintains the lymphoid microenvironment essential for GC formation and class-switched Ig responses.

  6. The Deterministic Dendritic Cell Algorithm

    CERN Document Server

    Greensmith, Julie

    2010-01-01

    The Dendritic Cell Algorithm is an immune-inspired algorithm orig- inally based on the function of natural dendritic cells. The original instantiation of the algorithm is a highly stochastic algorithm. While the performance of the algorithm is good when applied to large real-time datasets, it is difficult to anal- yse due to the number of random-based elements. In this paper a deterministic version of the algorithm is proposed, implemented and tested using a port scan dataset to provide a controllable system. This version consists of a controllable amount of parameters, which are experimented with in this paper. In addition the effects are examined of the use of time windows and variation on the number of cells, both which are shown to influence the algorithm. Finally a novel metric for the assessment of the algorithms output is introduced and proves to be a more sensitive metric than the metric used with the original Dendritic Cell Algorithm.

  7. IL-13Ra2- and glioma stem cell-pulsed dendritic cells induce glioma cell death in vitro

    Institute of Scientific and Technical Information of China (English)

    Ying Wang; Ruifan Xie; Hongquan Niu; Ting Lei

    2016-01-01

    Objective Gliomas are the most common malignant tumors in the central nervous system. Despite mul-tiple therapies including surgery, chemotherapy, and radiotherapy, the prognosis of patients remains poor. Immunotherapy is an alternative method of treating glioma, and the use of dendritic cel vaccines is one of the promising treatment options. However, there is no specific tumor cel antigen that can trigger dendritic cel s (DCs). IL-13Ra2 is a specific antigen expressed in glioma cel s; in the current study, we have at-tempted to explore whether IL-13Ra2 could be the antigen that triggers DCs and to envisage its application as potential therapy for glioma. Methods The expression of IL-13Ra2 was detected in U251 glioma cel lines and primary glioma tissues using dif erent methods. DCs from human blood were isolated and pulsed with recombinant IL-13Ra2, fol-lowing which the cytotoxicity of these DCs on glioma cel s was detected and analyzed. Results About 55.9% human glioma tissue cel s expressed IL-13Ra2, while normal brain tissue cel s did not show any expression. DC vaccines loaded with IL-13Ra2, glioma cel antigen, and brain tumor stem cel (BTSC) antigen could significantly stimulate the proliferation of T lymphocytes and induce cel death in the glioma tissue. Compared to other groups, DC vaccines loaded with BTSC antigen showed the strongest ability to activate cytotoxic T lymphocytes (CTLs), while the glioma cel antigen group showed no significant dif erence. Conclusion IL-13Ra2, which is expressed in gliomas and by glioma stem cel s, as wel as IL-13Ra2 could prove to be potential antigens for DC vaccine-based immunotherapy.

  8. Indoor pollutant hexabromocyclododecane enhances house dust mite-induced activation of human monocyte-derived dendritic cells.

    Science.gov (United States)

    Canbaz, Derya; Lebre, M Cristina; Logiantara, Adrian; van Ree, Ronald; van Rijt, Leonie S

    2016-11-01

    The indoor pollutant hexabromocyclododecane (HBCD) has been added as flame retardant to many consumer products but detaches and accumulates in house dust. Inhalation of house dust leads to exposure to house dust mite (HDM) allergens in the presence of HBCD. Activation of dendritic cells is crucial in the sensitization to HDM allergens. The current study examined whether exposure to HBCD affected activation/maturation of HDM-exposed human dendritic cells (DC). Human monocyte-derived DC (moDC) were exposed simultaneously to HDM and a concentration range of HBCD (0.1-20 μM) in vitro. HDM exposure of moDC induced expression of co-stimulatory molecule CD80 and production of pro-inflammatory cytokines interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF)-α. However, simultaneous exposure of moDC to HBCD and HDM enhanced the expression of antigen presenting molecule HLA-DR, co-stimulatory molecule CD86 and pro-inflammatory cytokine IL-8 depending on the dose of HBCD. Our results indicate that simultaneous exposure of HDM and HBCD can enhance the antigen presentation and maturation/activation of DC.

  9. Regulated assembly of vacuolar ATPase is increased during cluster disruption-induced maturation of dendritic cells through a phosphatidylinositol 3-kinase/mTOR-dependent pathway.

    Science.gov (United States)

    Liberman, Rachel; Bond, Sarah; Shainheit, Mara G; Stadecker, Miguel J; Forgac, Michael

    2014-01-17

    The vacuolar (H(+))-ATPases (V-ATPases) are ATP-driven proton pumps composed of a peripheral V1 domain and a membrane-embedded V0 domain. Regulated assembly of V1 and V0 represents an important regulatory mechanism for controlling V-ATPase activity in vivo. Previous work has shown that V-ATPase assembly increases during maturation of bone marrow-derived dendritic cells induced by activation of Toll-like receptors. This increased assembly is essential for antigen processing, which is dependent upon an acidic lysosomal pH. Cluster disruption of dendritic cells induces a semi-mature phenotype associated with immune tolerance. Thus, semi-mature dendritic cells are able to process and present self-peptides to suppress autoimmune responses. We have investigated V-ATPase assembly in bone marrow-derived, murine dendritic cells and observed an increase in assembly following cluster disruption. This increased assembly is not dependent upon new protein synthesis and is associated with an increase in concanamycin A-sensitive proton transport in FITC-loaded lysosomes. Inhibition of phosphatidylinositol 3-kinase with wortmannin or mTORC1 with rapamycin effectively inhibits the increased assembly observed upon cluster disruption. These results suggest that the phosphatidylinositol 3-kinase/mTOR pathway is involved in controlling V-ATPase assembly during dendritic cell maturation.

  10. Sirtuin 1 Regulates Dendritic Cell Activation and Autophagy during Respiratory Syncytial Virus-Induced Immune Responses.

    Science.gov (United States)

    Owczarczyk, Anna B; Schaller, Matthew A; Reed, Michelle; Rasky, Andrew J; Lombard, David B; Lukacs, Nicholas W

    2015-08-15

    Respiratory syncytial virus (RSV) is the major cause of lower respiratory tract infection in children worldwide. Sirtuin 1 (SIRT1), an NAD(+)-dependent deacetylase, has been associated with the induction of autophagy and the regulation of inflammatory mediators. We found that Sirt1 was upregulated in mouse lung after RSV infection. Infected animals that received EX-527, a selective SIRT1 inhibitor, displayed exacerbated lung pathology, with increased mucus production, elevated viral load, and enhanced Th2 cytokine production. Gene expression analysis of isolated cell populations revealed that Sirt1 was most highly upregulated in RSV-treated dendritic cells (DCs). Upon RSV infection, EX-527-treated DCs, Sirt1 small interfering RNA-treated DCs, or DCs from conditional knockout (Sirt1(f/f)-CD11c-Cre(+)) mice showed downregulated inflammatory cytokine gene expression and attenuated autophagy. Finally, RSV infection of Sirt1(f/f)-CD11c-Cre(+) mice resulted in altered lung and lymph node cytokine responses, leading to exacerbated pathology. These data indicate that SIRT1 promotes DC activation associated with autophagy-mediated processes during RSV infection, thereby directing efficient antiviral immune responses.

  11. Dendritic cells decreased the concomitant expanded Tregs and Tregs related IL-35 in cytokine-induced killer cells and increased their cytotoxicity against leukemia cells.

    Science.gov (United States)

    Pan, Ying; Tao, Qianshan; Wang, Huiping; Xiong, Shudao; Zhang, Rui; Chen, Tianping; Tao, Lili; Zhai, Zhimin

    2014-01-01

    Regulatory T cells (Tregs) are potent immunosuppressive cells and essential for inducing immune tolerance. Recent studies have reported that Tregs and Tregs related cytokines can inhibit the antitumor activity of cytokine-induced killer (CIK) cells, but dendritic cells co-cultured CIK (DC-CIK) cells can be used for induction of a specific immune response by blocking of Tregs and TGF-β, IL-10. As a novel identified cytokine, IL-35 is specially produced by Tregs and plays an essential role in immune regulation. However, it remains unknown whether IL-35 roles in tumor immunotherapy mediated by CIK and DC-CIK cells. In this study, we cultured CIK and DC-CIK cells from the same healthy adult samples, and investigated their phenotype, proliferation, cytotoxic activity against leukemia cell lines K562 and NB4 by FCM and CCK-8, measured IL-35, TGF-β and IL-10 protein by ELISA, detected Foxp3, IL-35 and IL-35 receptor mRNA by Real-time PCR, respectively. We found Tregs and IL-35 concomitantly expanded by a time-dependent way during the generation of CIK cells, but DC significantly down-regulated the expression of them and simultaneously up-regulated the proliferation ability as well as cytotoxic activity of CIK cells against leukemia cell lines. Therefore, our data suggested that DC decreased concomitant expanded Tregs and Tregs related IL-35 in CIK cells and might contribute to improve their cytotoxicity against leukemia cells in vitro.

  12. Staphylococcus aureus PSM peptides induce tolerogenic dendritic cells upon treatment with ligands of extracellular and intracellular TLRs.

    Science.gov (United States)

    Armbruster, Nicole S; Richardson, Jennifer R; Schreiner, Jens; Klenk, Juliane; Günter, Manina; Autenrieth, Stella E

    2016-12-01

    Dendritic cells (DCs) are key players of the immune system and thus a target for immune evasion by pathogens. We recently showed that the virulence factor phenol-soluble modulin (PSM) produced by community-associated methicillin-resistant Staphylococcus aureus strains induces tolerogenic DCs upon Toll-like receptor (TLR) 2 activation via the p38-CREB-IL-10 pathway. Here, we addressed the question whether this tolerogenic phenotype of DCs induced by PSMs is specific for TLR2 activation. Therefore, bone marrow-derived DCs were treated with various ligands for extracellular and intracellular TLRs simultaneously with PSMα3. We show that PSMα3 modulates antigen uptake, maturation and cytokine production of DCs activated by TLR1/2, TLR2/6, TLR4, TLR7, and TLR9. Pre-incubation of DCs with a p38 MAP kinase inhibitor prevented the PSMα3-induced IL-10 secretion, as well as MHC class II up-regulation upon TLR activation. In consequence, the tolerogenic DCs induced by PSMα3 in response to several TLR ligands promoted priming of regulatory T cells. Thus, PSMs could be useful as inducers of tolerogenic DCs upon TLR ligand stimulation for therapeutic applications.

  13. Dendritic cells star in Vancouver

    OpenAIRE

    Klechevsky, Eynav; Kato, Hiroki; Sponaas, Anne-Marit

    2005-01-01

    The fast-moving field of dendritic cell (DC) biology is hard to keep pace with. Here we report on advances from the recent Keystone Symposium, “Dendritic Cells at the Center of Innate and Adaptive Immunity,” organized in Vancouver, BC on Feb. 1–7, 2005 by Anne O'Garra, Jacques Banchereau, and Alan Sher. New insights into the molecular mechanisms of DC function and their influence on immune regulation, their role in infectious and autoimmune disease, and new clinical applications are highlight...

  14. Exposure of CD34+ precursors to cytostatic anthraquinone-derivatives induces rapid dendritic cell differentiation: implications for cancer immunotherapy.

    Science.gov (United States)

    van de Ven, Rieneke; Reurs, Anneke W; Wijnands, Pepijn G J T B; van Wetering, Sandra; Kruisbeek, Ada M; Hooijberg, Erik; Scheffer, George L; Scheper, Rik J; de Gruijl, Tanja D

    2012-02-01

    Appropriate activation of dendritic cells (DC) is essential for successful active vaccination and induction of cell-mediated immunity. The scarcity of precursor cells, as well as long culture methods, have hampered wide-scale application of DC vaccines derived from CD34(+) precursors, despite their suggested superior efficacy over the more commonly applied monocyte-derived DC (MoDC). Here, employing the CD34(+)/CD14(+) AML-derived human DC progenitor cell line MUTZ3, we show that cytostatic anthraquinone-derivatives (i.e., the anthracenedione mitoxantrone and the related anthracyclin doxorubicin) induce rapid differentiation of CD34(+) DC precursors into functional antigen-presenting cells (APC) in a three-day protocol. The drugs were found to act specifically on CD34(+), and not on CD14(+) DC precursors. Importantly, these observations were confirmed for primary CD34(+) and CD14(+) DC precursors from peripheral blood. Mitoxantrone-generated DC were fully differentiated within three days and after an additional 24 h of maturation, were as capable as standard 9-day differentiated and matured DC to migrate toward the lymph node-homing chemokines CCL19 and CCL21, to induce primary allogeneic T cell proliferation, and to prime functional MART1-specific CD8(+) T lymphocytes. Our finding that anthraquinone-derivatives like mitoxantrone support rapid high-efficiency differentiation of DC precursors may have consequences for in vitro production of DC vaccines as well as for novel immunochemotherapy strategies.

  15. Recombinant Lactobacillus plantarum induces immune responses to cancer testis antigen NY-ESO-1 and maturation of dendritic cells.

    Science.gov (United States)

    Mobergslien, Anne; Vasovic, Vlada; Mathiesen, Geir; Fredriksen, Lasse; Westby, Phuong; Eijsink, Vincent G H; Peng, Qian; Sioud, Mouldy

    2015-01-01

    Given their safe use in humans and inherent adjuvanticity, Lactic Acid Bacteria may offer several advantages over other mucosal delivery strategies for cancer vaccines. The objective of this study is to evaluate the immune responses in mice after oral immunization with Lactobacillus (L) plantarum WCFS1 expressing a cell-wall anchored tumor antigen NY-ESO-1. And to investigate the immunostimulatory potency of this new candidate vaccine on human dendritic cells (DCs). L. plantarum displaying NY-ESO-1 induced NY-ESO-1 specific antibodies and T-cell responses in mice. By contrast, L. plantarum displaying conserved proteins such as heat shock protein-27 and galectin-1, did not induce immunity, suggesting that immune tolerance to self-proteins cannot be broken by oral administration of L. plantarum. With respect to immunomodulation, immature DCs incubated with wild type or L. plantarum-NY-ESO-1 upregulated the expression of co-stimulatory molecules and secreted a large amount of interleukin (IL)-12, TNF-α, but not IL-4. Moreover, they upregulated the expression of immunosuppressive factors such as IL-10 and indoleamine 2,3-dioxygenase. Although L. plantarum-matured DCs expressed inhibitory molecules, they stimulated allogeneic T cells in-vitro. Collectively, the data indicate that L. plantarum-NY-ESO-1 can evoke antigen-specific immunity upon oral administration and induce DC maturation, raising the potential of its use in cancer immunotherapies.

  16. Plasmacytoid dendritic cells suppress HIV-1 replication but contribute to HIV-1 induced immunopathogenesis in humanized mice.

    Directory of Open Access Journals (Sweden)

    Guangming Li

    2014-07-01

    Full Text Available The role of plasmacytoid dendritic cells (pDC in human immunodeficiency virus type 1 (HIV-1 infection and pathogenesis remains unclear. HIV-1 infection in the humanized mouse model leads to persistent HIV-1 infection and immunopathogenesis, including type I interferons (IFN-I induction, immune-activation and depletion of human leukocytes, including CD4 T cells. We developed a monoclonal antibody that specifically depletes human pDC in all lymphoid organs in humanized mice. When pDC were depleted prior to HIV-1 infection, the induction of IFN-I and interferon-stimulated genes (ISGs were abolished during acute HIV-1 infection with either a highly pathogenic CCR5/CXCR4-dual tropic HIV-1 or a standard CCR5-tropic HIV-1 isolate. Consistent with the anti-viral role of IFN-I, HIV-1 replication was significantly up-regulated in pDC-depleted mice. Interestingly, the cell death induced by the highly pathogenic HIV-1 isolate was severely reduced in pDC-depleted mice. During chronic HIV-1 infection, depletion of pDC also severely reduced the induction of IFN-I and ISGs, associated with elevated HIV-1 replication. Surprisingly, HIV-1 induced depletion of human immune cells including T cells in lymphoid organs, but not the blood, was reduced in spite of the increased viral replication. The increased cell number in lymphoid organs was associated with a reduced level of HIV-induced cell death in human leukocytes including CD4 T cells. We conclude that pDC play opposing roles in suppressing HIV-1 replication and in promoting HIV-1 induced immunopathogenesis. These findings suggest that pDC-depletion and IFN-I blockade will provide novel strategies for treating those HIV-1 immune non-responsive patients with persistent immune activation despite effective anti-retrovirus treatment.

  17. Bone marrow-derived dendritic cells.

    Science.gov (United States)

    Roney, Kelly

    2013-01-01

    While much is understood about dendritic cells and their role in the immune system, the study of these cells is critical to gain a more complete understanding of their function. Dendritic cell isolation from mouse body tissues can be difficult and the number of cells isolated small. This protocol describes the growth of large number of dendritic cells from the culture of mouse bone marrow cells. The dendritic cells grown in culture facilitate experiments that may require large number of dendritic cells without great expense or use of large number of mice.

  18. Protein-induced changes during the maturation process of human dendritic cells: A 2-D DIGE approach

    DEFF Research Database (Denmark)

    Ferreira, Gb; Overbergh, L; Hansen, Kasper Lage

    2008-01-01

    Dendritic cells (DCs) are unique antigen presenting cells, which upon maturation change from a specialized antigen-capturing cell towards a professional antigen presenting cells. In this study, a 2-D DIGE analysis of immature and mature DCs was performed, to identify proteins changing in expressi...

  19. Comparative analysis of dendritic cells transduced with different anti-apoptotic molecules: sensitivity to tumor-induced apoptosis.

    Science.gov (United States)

    Balkir, Levent; Tourkova, Irina L; Makarenkova, Valeria P; Shurin, Galina V; Robbins, Paul D; Yin, Xiao-Ming; Chatta, Gurkamal; Shurin, Michael R

    2004-05-01

    Tumors develop mechanisms to escape recognition by the immune system. It has recently been demonstrated that tumors cause apoptotic death of key immune cells, including the major antigen-presenting cells, dendritic cells (DC). Elimination of DC from the tumor environment significantly diminishes development of specific immunologic responses. We have recently demonstrated that tumor-induced DC apoptosis could be prevented by overexpression of the anti-apoptotic molecule Bcl-x(L). The aim of this study was to identify extrinsic and intrinsic tumor-induced apoptotic pathways in DC by targeting different anti-apoptotic molecules, including FLIP, XIAP/hILP, dominant-negative procaspase-9 and HSP70. Murine bone marrow derived DC were transduced with adenoviral vectors carrying different anti-apoptotic molecules and co-incubated with tumor cells in a Transwell system. Apoptosis of DC was assessed by Annexin V and PI staining. We have demonstrated that adenoviral infection of DC with genes encoding different anti-apoptotic molecules exhibits different degrees of resistance to melanoma-induced apoptosis. Furthermore, we have shown that anti-apoptotic molecules other than the Bcl-2 family of proteins are able to protect DC and prevent tumor-induced apoptosis in DC. The results show that tumor-induced apoptosis of DC is not limited to the mitochondrial pathway of cell death and open additional possibilities for targeted molecular protection of DC longevity in cancer. Therefore, effective protection of DC from tumor-induced apoptosis may significantly improve the efficacy of DC-based therapies for cancer. Copyright 2004 John Wiley & Sons, Ltd.

  20. HIV-1-triggered release of type I IFN by plasmacytoid dendritic cells induces BAFF production in monocytes.

    Science.gov (United States)

    Gomez, Alejandro M; Ouellet, Michel; Tremblay, Michel J

    2015-03-01

    HIV-1 infection leads to numerous B cell abnormalities, including hypergammaglobulinemia, nonspecific B cell activation, nonspecific class switching, increased cell turnover, breakage of tolerance, increased immature/transitional B cells, B cell malignancies, as well as a loss of capacity to generate and maintain memory, all of which contribute to a global impairment of the immune humoral compartment. Several cytokines and soluble factors, which are increased in sera of HIV-1-infected individuals, have been suggested to directly or indirectly contribute to these B cell dysfunctions, and one of these is the B cell-activating factor (BAFF). We report in this study that HIV-1 (X4- and R5-tropic) upregulates BAFF expression and secretion by human monocytes. Moreover, we show that the virus-mediated production of BAFF by monocytes relies on a type I IFN response by a small percentage of plasmacytoid dendritic cells (pDCs) present in the monocyte cultures. HIV-1-induced type I IFN by pDCs triggers BAFF production in both classical and intermediate monocytes, but not in nonclassical monocytes, which nonetheless display a very strong basal BAFF production. We report also that basal BAFF secretion was higher in monocytes obtained from females compared with those from male donors. This study provides a novel mechanistic explanation for the increased BAFF levels observed during HIV-1 infection and highlights the importance of pDC/monocyte crosstalk to drive BAFF secretion. Copyright © 2015 by The American Association of Immunologists, Inc.

  1. Cell death induced by application of time-varying magnetic fields on nanoparticle-loaded dendritic cells

    CERN Document Server

    Marcos-Campos, I; Torres, T E; Marquina, C; Tres, A; Ibarra, M R; Goya, G F

    2010-01-01

    Aim: To assess the capability of monocyte-derived dendritic cells (DCs) to take Fe3O4 magnetic nanoparticles (MNPs), keeping their viability. To provoke cell death on these MNPs-loaded DCs using an external alternating magnetic field (AMF). Material & methods: Peripheral blood mononuclear cells were isolated from normal blood and platelets removed by centrifugation. Immunoselected CD14+ cells were cultured for 5 days, and the resulting cell phenotype was determined against several markers using flow cytometry. Co-cultures of DCs and MNPs were done overnight. The amount of Fe3O4 nanoparticles incorporated by DCs was quantified by magnetization measurements. MNPs-loaded DCs were exposed to AMF for 30 min and then cell viability was measured using trypan blue and FACS (annexin-propidium iodide) protocols. Morphological changes were investigated using scanning electron microscopy. Results: No significant decrease in cell viability of MNP/loaded DCs was observed up to five days, as compared against control sam...

  2. Targeting vaccines to dendritic cells.

    Science.gov (United States)

    Foged, Camilla; Sundblad, Anne; Hovgaard, Lars

    2002-03-01

    Dendritic cells (DC) are specialized antigen presenting cells (APC) with a remarkable ability to take up antigens and stimulate major histocompatibility complex (MHC)-restricted specific immune responses. Recent discoveries have shown that their role in initiating primary immune responses seems to be far superior to that of B-cells and macrophages. DC are localized at strategic places in the body at sites used by pathogens to enter the organism, and are thereby in an optimal position to capture antigens. In general, vaccination strategies try to mimic the invasiveness of the pathogens. DC are considered to play a central role for the provocation of primary immune responses by vaccination. A rational way of improving the potency and safety of new and already existing vaccines could therefore be to direct vaccines specifically to DC. There is a need for developing multifunctional vaccine drug delivery systems (DDS) with adjuvant effect that target DC directly and induce optimal immune responses. This paper will review the current knowledge of DC physiology as well as the progress in the field of novel vaccination strategies that directly or indirectly aim at targeting DC.

  3. Immune tolerance induced by adoptive transfer of dendritic cells in an insulin-dependent diabetes mellitus routine model

    Institute of Scientific and Technical Information of China (English)

    Cheng-liang ZHANG; Xiao-lei ZOU; Jia-bei PENG; Ming XIANG

    2007-01-01

    Aim: To investigate the effect and underlying mechanisms of inunune-tolerance induced by the adoptive transfer of bone marrow (BM)-derived dendritic cells (DC) in insulin-dependent diabetes mellitus (IDDM) mice. Methods: The IDDM model was established by a low dose of streptozotocin (STZ) in Balb/c mice. Two DC subpopulations were generated from the BM cells with granulocyte-macroph-age colony-stimulating factor with or without interleukin-4. The purity and the T cell stimulatory capability of DC were identified. These cells were used to modu-late autoimmune response in pre-diabetic mice. Blood glucose was examined weekly; pancreas tissues were taken for histopathological analysis, and CD4+ T cells were isolated to detect lymphocyte proliferation by MTT assay and the ratio of CD4+CD25+ T cells by fluorescence-activated cell sorting (FACS). The cytokine secretion was determined by ELISA analysis. Results: Two DC subsets were generated from BM, which have phenotypes of mature DC (mDC) and immature DC (iDC), respectively. The level of blood glucose decreased significantly by transferring iDC (P<0.01) rather than mDC. Less lymphocyte infiltration was ob-served in the islets, and pancreatic structure was intact. In vitro, proliferation of lymphocytes decreased and the proportion of CD4+CD25+ T cells increased remarkably, compared with the mDC-treated groups (P<0.05), which were associ-ated with increased level of the Th2 cytokine and reduced level of the Th1 cytokine after iDC transfer. Conclusion: Our data showed that iDC transfer was able to confer protection to mice from STZ-induced IDDM. The immune-tolerance to IDDM may be associated with promoting the production of CD4+CD25+ T cells and inducing regulatory Th2 responses in vivo.

  4. Study on the immune responses against pancreatic cancer induced by mucin 4 and human telomerase reverse transcriptase mRNA co-transfected dendritic cells in vitro

    Institute of Scientific and Technical Information of China (English)

    陈江

    2014-01-01

    Objective To investigate the anti-tumor immune response induced by human pancreatic cancer mucin 4mRNA and human telomerase reverse transcriptase(hTERT)mRNA cotransfected dendritic cells(DC),and to provide the experimental evidences for the treatment of pancreatic cancer with multi-epitope loaded DC vaccine.Methods DC were isolated from peripheral DC.

  5. Novel analysis of maturation of murine bone-marrow-derived dendritic cells induced by Ginkgo Seed Polysaccharides.

    Science.gov (United States)

    Chen, Yinghan; Meng, Yiming; Cao, Yan; Wen, Hua; Luo, Hong; Gao, Xinghua; Shan, Fengping

    2015-01-01

    Our understanding of the mechanisms of effect of Ginkgo Seed Polysaccharides (GSPs) on the immune system remains unclear. The aim of this work was to investigate the effect of GSPs on the maturation and function of bone-marrow-derived dendritic cells (BMDCs). The results demonstrate that GSP could exert positive immune modulation on the maturation and functions of BMDCs. This effect was evidenced by decreased changes of phagosome number inside BMDCs, decreased activity of acidic phosphatase (ACP), decreased phagocytosis of BMDCs, and increased changes of key membrane molecules on BMDCs. Upregulated production of cytokines IL-12 and TNF-α also was confirmed. Therefore, it can be concluded that GSPs can efficiently induce the maturation of BMDCs. Our exploration provides direct data and a rationale for potential application of GSPs as an immune enhancer in improving immunity and as a potent adjuvant in the design of DC-based vaccines.

  6. Phagocytosis of Picornavirus-Infected Cells Induces an RNA-Dependent Antiviral State in Human Dendritic Cells▿

    Science.gov (United States)

    Kramer, Matthijs; Schulte, Barbara M.; Toonen, Liza W. J.; Barral, Paola M.; Fisher, Paul B.; Lanke, Kjerstin H. W.; Galama, Jochem M. D.; van Kuppeveld, Frank J. M.; Adema, Gosse J.

    2008-01-01

    Dendritic cells (DCs) play a central role in instructing antiviral immune responses. DCs, however, can become targeted by different viruses themselves. We recently demonstrated that human DCs can be productively infected with echoviruses (EVs), but not coxsackie B viruses (CVBs), both of which are RNA viruses belonging to the Enterovirus genus of the Picornaviridae family. We now show that phagocytosis of CVB-infected, type I interferon-deficient cells induces an antiviral state in human DCs. Uptake of infected cells increased the expression of the cytoplasmic RNA helicases retinoic acid-inducible gene I and melanoma differentiation-associated gene 5 as well as other interferon-stimulated genes and protected DCs against subsequent infection with EV9. These effects depended on recognition of viral RNA and could be mimicked by exposure to the synthetic double-stranded RNA analogue poly(I:C) but not other Toll-like receptor (TLR) ligands. Blocking endosomal acidification abrogated protection, suggesting a role for TLRs in the acquisition of an antiviral state in DCs. In conclusion, recognition of viral RNA rapidly induces an antiviral state in human DCs. This might provide a mechanism by which DCs protect themselves against viruses when attracted to an environment with ongoing infection. PMID:18184700

  7. Cestode Antigens Induce a Tolerogenic-Like Phenotype and Inhibit LPS Inflammatory Responses in Human Dendritic Cells

    Directory of Open Access Journals (Sweden)

    César A. Terrazas, Fausto Sánchez-Muñoz, Ana M. Mejía-Domínguez, Luis M. Amezcua-Guerra, Luis I. Terrazas, Rafael Bojalil, Lorena Gómez-García

    2011-01-01

    Full Text Available Pathogens have developed strategies to modify Dendritic Cells (DCs phenotypes and impair their functions in order to create a safer environment for their survival. DCs responses to helminths and their derivatives vary among different studies. Here we show that excretory/secretory products of the cestode Taenia crassiceps (TcES do not induce the maturation of human DCs judged by a lack of increment in the expression of CD83, HLA-DR, CD80 and CD86 molecules but enhanced the production of IL-10 and positively modulated the expression of the C-type lectin receptor MGL and negatively modulated the expression of DC-SIGN. Additionally, these antigens were capable of down-modulating the inflammatory response induced by LPS in these cells by reducing the expression of the maturation markers and the production of the inflammatory cytokines IL-1β, TNF, IL-12 and IL-6. The effects of TcES upon the DCs responses to LPS were stronger if cells were exposed during their differentiation to the helminth antigens. All together, these findings suggest the ability of TcES to induce the differentiation of human DCs into a tolerogenic-like phenotype and to inhibit the effects of inflammatory stimuli.

  8. Bone marrow-derived dendritic cells pulsed with tumor lysates induce anti-tumor immunity against gastric cancer ex vivo

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    AIM: To investigate whether bone marrow-derived denritic cells pulsed with tumor lysates induce immunity against gastric cancer ex vivo. METHODS: c-kit+ hematopoietic progenitor cells were magnetically isolated with a MiniMACS separator from BALB/c mice bone marrow cells. These cells were cultured with cytokines GM-CSF, IL-4, and TNFα to induce their maturation. They were analysed by morphological observation, phenotype analysis, and mixed lymphocyte reaction (MLR). Bone marrow-derived DCs (BM-DCs) were pulsed with tumor cell lysate obtained by rapid freezing and thawing at a 1:3 DC:tumor cell ratio. Finally, cytotoxic T lymphocyte (CTL) activity and interferon gamma (IFNy) secretion was evaluated ex vivo.RESULTS: c-kit+ hematopoietic progenitor cells from mice bone marrow cells cultured with cytokines for 8 d showed the character of typical mature DCs. Norphologically, observed by light microscope, these cells were large with oval or irregularly shaped nuclei and with many small dendrites. Phenotypically, FACS analysis showed that they expressed.high levels of Ia, DEC-205, CD11b, CD80 and CD86 antigen, moderate levels of CD40, and negative for F4/80. Functionally, these ceils gained the capacity to stimulate allogeneic T cells in MLR assay. However, immature DCs cultured with cytokines for 5 d did not have typical DCs phenotypic markers and could not stimulate allogeneic T cells. Ex vivo primed T cells with SGC-7901 tumor cell lysate-pulsed (TP) DCs were able to induce effective CTL activity against SGC-7901 tumor cells (E:T = 100:1, 69.55% ± 6.05% specific lysis), but not B16 tumor cells, and produced higher levels of IFNγ, when stimulated with SGC-7901 tumor cells but not when stimulated with B16 tumor cells (1575.31 ± 60.25 pg/mL in SGC-7901 group vs 164.11 ± 18.52 pg/mL in B16 group, P < 0.01).CONCLUSION: BM-derived DCs pulsed with tumor lysates can induce anti-tumor immunity specific to gastric cancer ex vivo.

  9. Novel avian influenza A (H7N9 virus induces impaired interferon responses in human dendritic cells.

    Directory of Open Access Journals (Sweden)

    Veera Arilahti

    Full Text Available In March 2013 a new avian influenza A(H7N9 virus emerged in China and infected humans with a case fatality rate of over 30%. Like the highly pathogenic H5N1 virus, H7N9 virus is causing severe respiratory distress syndrome in most patients. Based on genetic analysis this avian influenza A virus shows to some extent adaptation to mammalian host. In the present study, we analyzed the activation of innate immune responses by this novel H7N9 influenza A virus and compared these responses to those induced by the avian H5N1 and seasonal H3N2 viruses in human monocyte-derived dendritic cells (moDCs. We observed that in H7N9 virus-infected cells, interferon (IFN responses were weak although the virus replicated as well as the H5N1 and H3N2 viruses in moDCs. H7N9 virus-induced expression of pro-inflammatory cytokines remained at a significantly lower level as compared to H5N1 virus-induced "cytokine storm" seen in human moDCs. However, the H7N9 virus was extremely sensitive to the antiviral effects of IFN-α and IFN-β in pretreated cells. Our data indicates that different highly pathogenic avian viruses may show considerable differences in their ability to induce host antiviral responses in human primary cell models such as moDCs. The unexpected appearance of the novel H7N9 virus clearly emphasizes the importance of the global influenza surveillance system. It is, however, equally important to systematically characterize in normal human cells the replication capacity of the new viruses and their ability to induce and respond to natural antiviral substances such as IFNs.

  10. Divergent signaling pathways regulate IL-12 production induced by different species of Lactobacilli in human dendritic cells.

    Science.gov (United States)

    Amar, Yacine; Rizzello, Valeria; Cavaliere, Riccardo; Campana, Stefania; De Pasquale, Claudia; Barberi, Chiara; Oliveri, Daniela; Pezzino, Gaetana; Costa, Gregorio; Meddah, Aicha Tirtouil; Ferlazzo, Guido; Bonaccorsi, Irene

    2015-07-01

    Recent studies have indicated that different strains of Lactobacilli differ in their ability to regulate IL-12 production by dendritic cells (DCs), as some strains are stronger inducer of IL-12 while other are not and can even inhibit IL-12 production stimulated by IL-12-inducer Lactobacilli. In this report we demonstrate that Lactobacillus reuteri 5289, as previously described for other strains of L. reuteri, can inhibit DC production of IL-12 induced by Lactobacilllus acidophilus NCFM. Remarkably, L. reuteri 5289 was able to inhibit IL-12 production induced not only by Lactobacilli, as so far reported, but also by bacteria of different genera, including pathogens. We investigated in human DCs the signal transduction pathways involved in the inhibition of IL-12 production induced by L. reuteri 5289, showing that this potential anti-inflammatory activity, which is also accompanied by an elevated IL-10 production, is associated to a prolonged phosphorilation of ERK1/2 MAP kinase pathway. Improved understanding of the immune regulatory mechanisms exerted by Lactobacilli is crucial for a more precise employment of these commensal bacteria as probiotics in human immune-mediated pathologies, such as allergies or inflammatory bowel diseases.

  11. Direct infection of dendritic cells during chronic viral infection suppresses antiviral T cell proliferation and induces IL-10 expression in CD4 T cells.

    Directory of Open Access Journals (Sweden)

    Carmen Baca Jones

    Full Text Available Elevated levels of systemic IL-10 have been associated with several chronic viral infections, including HCV, EBV, HCMV and LCMV. In the chronic LCMV infection model, both elevated IL-10 and enhanced infection of dendritic cells (DCs are important for viral persistence. This report highlights the relationship between enhanced viral tropism for DCs and the induction of IL-10 in CD4 T cells, which we identify as the most frequent IL-10-expressing cell type in chronic LCMV infection. Here we report that infected CD8αneg DCs express elevated IL-10, induce IL-10 expression in LCMV specific CD4 T cells, and suppress LCMV-specific T cell proliferation. DCs exposed in vivo to persistent LCMV retain the capacity to stimulate CD4 T cell proliferation but induce IL-10 production by both polyclonal and LCMV-specific CD4 T cells. Our study delineates the unique effects of direct infection versus viral exposure on DCs. Collectively these data point to enhanced infection of DCs as a key trigger of the IL-10 induction cascade resulting in maintenance of elevated IL-10 expression in CD4 T cells and inhibition of LCMV-specific CD4 and CD8 T cell proliferation.

  12. A novel polysaccharide from the seeds of Plantago asiatica L. induces dendritic cells maturation through toll-like receptor 4.

    Science.gov (United States)

    Huang, Danfei; Nie, Shaoping; Jiang, Leming; Xie, Mingyong

    2014-02-01

    In this study, we investigated the effect of a polysaccharide purified from the seeds of Plantago asiatica L. (PLP-2) on the phenotypic and functional maturation of murine bone marrow-derived dendritic cells (DCs) and relevant mechanisms. The results showed that PLP-2 increased the expression of maturation markers major histocompatibility complex II, CD86, CD80, and CD40 on DCs. Consistent with the changes in the phenotypic markers, functional assay for DCs maturation showed that PLP-2 decreased DCs endocytosis and increased intracellular interleukin (IL)-12 levels and allostimulatory activity. Furthermore, using a syngeneic T cell activation model, we found that PLP-2 treated DCs presented ovalbumin antigen to T cells more efficiently as demonstrated by increased T cell proliferation. In addition, the effects of PLP-2 on DCs were significantly impaired by treating the cells with anti-TLR4 antibody prior to PLP-2 treatment, implying direct interaction between PLP-2 and TLR4 on cell surface. These results suggested that PLP-2 may induce DCs maturation through TLR4. Our results may have important implications for our understanding on the molecular mechanisms of immunopotentiating action of the polysaccharides from plants.

  13. Potentially probiotic bacteria induce efficient maturation but differential cytokine production in human monocyte-derived dendritic cells

    Institute of Scientific and Technical Information of China (English)

    Sinikka Latvala; Taija E Pietil(a); Ville Veckman; Riina A Kekkonen; Soile Tynkkynen; Riitta Korpela; Ilkka Julkunen

    2008-01-01

    MM: To analyze the ability of nine different potentially probiotic bacteria to induce maturation and cytokine production in human monocyLe-derived dendritic cells (moDCs).METHODS: Cytokine production and maturation of moDCs in response to bacterial stimulation was analyzed with enzyme-linked immunosorbent assay (ELISA) and flow cytometric analysis (FACS),respectively.The kinetics of mRNA expression of cytokine genes was determined by Northern blotting.The involvement of different signaling pathways in cytokine gene expression was studied using specific pharmacological signaling inhibitors.RESULTS: All studied bacteria induced the maturation of moDCs in a dose-dependent manner.More detailed analysis with S.thermophilus THS,B.breve Bb99,and L.lactis subsp,cremoris ARH74 indicated that these bacteria induced the expression of moDC maturation markers HLA class II and CD86 as efficiently as pathogenic bacteria.However,these bacteria differed in their ability to induce moDC cytokine gene expression.S.therrnophilus induced the expression of pro-inflammatory (TNF-a,IL-12,IL-6,and CCL20)and Th1 type (IL-12 and IFN-y) cytokines,while B.breve and L.lactis were also potent inducers of antiinflammatory IL-10.Mitogen-activated protein kinase (MAPK) p38,phosphatidylinositol 3 (PI3) kinase,and nuclear factor-kappa B (NF-κB) signaling pathways were shown to be involved in bacteria-induced cytokine production.CONCLUSION: Our results indicate that potentially probiotic bacteria are able to induce moDC maturation,but their ability to induce cytokine gene expression varies significantly from one bacterial strain to another.

  14. G1-4A, a polysaccharide from Tinospora cordifolia induces peroxynitrite dependent killer dendritic cell (KDC) activity against tumor cells.

    Science.gov (United States)

    Pandey, Vipul K; Amin, Prayag J; Shankar, Bhavani S

    2014-12-01

    Dendritic cells (DC) play a central role in the development of an adaptive immune response against tumor. In addition to its role in antigen presentation, DC also possesses cytotoxic activity against tumor cells. We have earlier shown phenotypic and functional maturation of bone marrow derived dendritic cells (BMDC) by G1-4A, an arabinogalactan derived from Tinospora cordifolia. In this study, we have investigated the killer phenotype of BMDC matured in the presence of G1-4A, [mBMDC (G1-4A)] on tumor cells. We have observed several fold increase in killing of tumor cells by mBMDC (G1-4A). The tumoricidal activity was not specific to syngeneic tumors cells but could kill xenogenic tumors also. Nitric oxide released by mBMDC (G1-4A) generates peroxynitrite in tumor cells and is responsible for killing of target cells. This killing was completely abrogated by inducible nitric oxide synthase (iNOS) inhibitor 1400W and NADPH oxidase inhibitor apocyanin. The killed target cells are phagocytosed by BMDC which further activate syngeneic cytotoxic T cells. These results thus show that G1-4A treated mBMDC acquire killer phenotype along with maturation which plays an important role in activation of cytotoxic T cells.

  15. Nucleosides from Phlebotomus papatasi salivary gland ameliorate murine collagen-induced arthritis by impairing dendritic cell functions.

    Science.gov (United States)

    Carregaro, Vanessa; Sá-Nunes, Anderson; Cunha, Thiago M; Grespan, Renata; Oliveira, Carlo J F; Lima-Junior, Djalma S; Costa, Diego L; Verri, Waldiceu A; Milanezi, Cristiane M; Pham, Van My; Brand, David D; Valenzuela, Jesus G; Silva, João S; Ribeiro, José M C; Cunha, Fernando Q

    2011-10-15

    Among several pharmacological compounds, Phlebotomine saliva contains substances with anti-inflammatory properties. In this article, we demonstrated the therapeutic activity of salivary gland extract (SGE) of Phlebotomus papatasi in an experimental model of arthritis (collagen-induced arthritis [CIA]) and identified the constituents responsible for such activity. Daily administration of SGE, initiated at disease onset, attenuated the severity of CIA, reducing the joint lesion and proinflammatory cytokine release. In vitro incubation of dendritic cells (DCs) with SGE limited specific CD4(+) Th17 cell response. We identified adenosine (ADO) and 5'AMP as the major salivary molecules responsible for anti-inflammatory activities. Pharmacologic inhibition of ADO A2(A) receptor or enzymatic catabolism of salivary nucleosides reversed the SGE-induced immunosuppressive effect. Importantly, CD73 (ecto-5'-nucleotidase enzyme) is expressed on DC surface during stage of activation, suggesting that ADO is also generated by 5'AMP metabolism. Moreover, both nucleosides mimicked SGE-induced anti-inflammatory activity upon DC function in vitro and attenuated establishment of CIA in vivo. We reveal that ADO and 5'AMP are present in pharmacological amounts in P. papatasi saliva and act preferentially on DC function, consequently reducing Th17 subset activation and suppressing the autoimmune response. Thus, it is plausible that these constituents might be promising therapeutic molecules to target immune inflammatory diseases.

  16. Dust mite allergen, glutathione S-transferase, induces T cell immunoglobulin mucin domain-4 in dendritic cells to facilitate initiation of airway allergy.

    Science.gov (United States)

    Mo, L-H; Yang, L-T; Zeng, L; Xu, L-Z; Zhang, H-P; Li, L-J; Liu, J-Q; Xiao, X-J; Zheng, P-Y; Liu, Z-G; Yang, P-C

    2017-02-01

    Allergens from dust mites play a critical role in the pathogenesis of airway allergy. The mechanism by which dust mite allergens induce allergic diseases is not fully understood yet. This study tests a hypothesis that the eighth subtypes of Dermatophagoides farina allergen (Derf8) play an important role in the induction of airway allergy. The protein of Derf8 was synthesized via molecular cloning approach. Dendritic cells (DC) were stimulated with Derf8 in the culture, and then, the expression of T cell immunoglobulin mucin domain 4 (TIM4) in dendritic cells (DC) was analysed. The role of Derf8 in the induction of airway allergy was evaluated with a mouse model. Exposure to Derf8 markedly induced the TIM4 expression in DCs by modulating the chromatin at the TIM4 promoter locus. Derf8 played a critical role in the expansion of the T helper 2 response in the mouse airway via inducing DCs to produce TIM4. Administration with Derf8-depleted dust mite extracts (DME) inhibited the allergic inflammation and induced regulatory T cells in mice with airway allergy. Derf8 plays an important role in the initiation of dust mite allergy. Vaccination with Derf8-deficient DME is more efficient to inhibit the dust mite allergic inflammation than using wild DME. © 2016 John Wiley & Sons Ltd.

  17. Ascaris lumbricoides pseudocoelomic body fluid induces a partially activated dendritic cell phenotype with Th2 promoting ability in vivo.

    Science.gov (United States)

    Dowling, David J; Noone, Cariosa M; Adams, Paul N; Vukman, Krisztina V; Molloy, Sile F; Forde, Jessica; Asaolu, Samuel; O'Neill, Sandra M

    2011-02-01

    Dendritic cells (DCs) matured with helminth-derived molecules that promote Th2 immune responses do not follow conventional definitions of DC maturation processes. While a number of models of DC maturation by Th2 stimuli are postulated, further studies are required if we are to clearly define DC maturation processes that lead to Th2 immune responses. In this study, we examine the interaction of Th2-inducing molecules from the parasitic helminth Ascaris lumbricoides with the maturation processes and function of DCs. Here we show that murine bone marrow-derived DCs are partially matured by A. lumbricoides pseudocoelomic body fluid (ABF) as characterised by the production of IL-6, IL-12p40 and macrophage inflammatory protein 2 (MIP-2) but no enhanced expression of cluster of differentiation (CD)-14, T-cell co-stimulatory markers CD80, CD86, CD40, OX40L and major histocompatibility complex class II was observed. Despite these phenotypic characteristics, ABF-stimulated DCs displayed the functional hallmarks of fully matured cells, enhancing DC phagocytosis and promoting Th2-type responses in skin-draining lymph node cells in vivo. ABF activated Th2-associated extracellular signal-regulated kinase-1 and nuclear factor-kB intracellular signalling pathways independently of toll-like receptor 4. Taken together, we believe this is the first paper to demonstrate A. lumbricoides murine DC-Th cell-driven responses shedding further light on DC maturation processes by helminth antigens.

  18. Dendritic cells and contact dermatitis.

    Science.gov (United States)

    Sasaki, Yoshinori; Aiba, Setsuya

    2007-10-01

    Contact dermatitis is a biological response to simple chemicals in the skin. Although it is well known that allergic contact dermatitis is mediated by the immune system, it is still uncertain whether it is a kind of protective response or it is simply an unnecessary response. We have demonstrated the following: (1) haptens activate Langerhans cells in the initiation phase of murine allergic contact dermatitis in vivo, (2) haptens activate human monocyte-derived dendritic cells in vitro, (3) the activation of dendritic cells by haptens is primarily mediated by the activation of p38 mitogen-activated protein kinase (MAPK), and (4) the activation of p38 MAPK is mediated by stimulation related to an imbalance of intracellular redox. Based on these observations, we will discuss the biological significance of contact dermatitis. In addition, we will review some up-to-date findings on Langerhans cell biology.

  19. Melanoma immunotherapy: dendritic cell vaccines

    OpenAIRE

    Lozada-Requena, Ivan; Laboratorios de Inmunología #108, Laboratorio de investigación y Desarrollo, Facultad de Ciencieas y Filosofía, Universidad Cayetano Heredia. Lima, Perú Empresa de Investigación y Desarrollo en Cáncer (EMINDES) SAC. Lima, Perú.; Núñez, César; Empresa de Investigación y Desarrollo en Cáncer (EMINDES) SAC. Lima, Perú.; Aguilar, José Luis; Laboratorios de Inmunología #108, Laboratorio de investigación y Desarrollo, Facultad de Ciencieas y Filosofía, Universidad Cayetano Heredia. Lima, Perú.

    2015-01-01

    This is a narrative review that shows accessible information to the scientific community about melanoma and immunotherapy.Dendritic cells have the ability to participate in innate and adaptive immunity, but are not unfamiliar to the immune evasion oftumors. Knowing the biology and role has led to generate in vitro several prospects of autologous cell vaccines against diversetypes of cancer in humans and animal models. However, given the low efficiency they have shown, we must implementstrateg...

  20. Sensitivity of Dendritic Cells to Microenvironment Signals

    Science.gov (United States)

    Motta, Juliana Maria; Rumjanek, Vivian Mary

    2016-01-01

    Dendritic cells are antigen-presenting cells capable of either activating the immune response or inducing and maintaining immune tolerance. They do this by integrating stimuli from the environment and changing their functional status as a result of plasticity. The modifications suffered by these cells have consequences in the way the organism may respond. In the present work two opposing situations known to affect dendritic cells are analyzed: tumor growth, leading to a microenvironment that favors the induction of a tolerogenic profile, and organ transplantation, which leads to a proinflammatory profile. Lessons learned from these situations may help to understand the mechanisms of modulation resulting not only from the above circumstances, but also from other pathologies. PMID:27088097

  1. Sensitivity of Dendritic Cells to Microenvironment Signals

    Directory of Open Access Journals (Sweden)

    Juliana Maria Motta

    2016-01-01

    Full Text Available Dendritic cells are antigen-presenting cells capable of either activating the immune response or inducing and maintaining immune tolerance. They do this by integrating stimuli from the environment and changing their functional status as a result of plasticity. The modifications suffered by these cells have consequences in the way the organism may respond. In the present work two opposing situations known to affect dendritic cells are analyzed: tumor growth, leading to a microenvironment that favors the induction of a tolerogenic profile, and organ transplantation, which leads to a proinflammatory profile. Lessons learned from these situations may help to understand the mechanisms of modulation resulting not only from the above circumstances, but also from other pathologies.

  2. Fasciola hepatica Kunitz type molecule decreases dendritic cell activation and their ability to induce inflammatory responses.

    Directory of Open Access Journals (Sweden)

    Cristian R Falcón

    Full Text Available The complete repertoire of proteins with immunomodulatory activity in Fasciola hepatica (Fh has not yet been fully described. Here, we demonstrated that Fh total extract (TE reduced LPS-induced DC maturation, and the DC ability to induce allogeneic responses. After TE fractionating, a fraction lower than 10 kDa (F<10 kDa was able to maintain the TE properties to modulate the DC pro- and anti-inflammatory cytokine production induced by LPS. In addition, TE or F<10 kDa treatment decreased the ability of immature DC to stimulate the allogeneic responses and induced a novo allogeneic CD4+CD25+Foxp3+ T cells. In contrast, treatment of DC with T/L or F<10 kDa plus LPS (F<10/L induced a regulatory IL-27 dependent mechanism that diminished the proliferative and Th1 and Th17 allogeneic responses. Finally, we showed that a Kunitz type molecule (Fh-KTM, present in F<10 kDa, was responsible for suppressing pro-inflammatory cytokine production in LPS-activated DC, by printing tolerogenic features on DC that impaired their ability to induce inflammatory responses. These results suggest a modulatory role for this protein, which may be involved in the immune evasion mechanisms of the parasite.

  3. Murine dendritic cells generated under serum-free conditions have a mature phenotype and efficiently induce primary immune responses.

    Science.gov (United States)

    Warncke, Max; Dodero, Anna; Dierbach, Heide; Follo, Marie; Veelken, Hendrik

    2006-03-20

    Vaccination with in vitro-generated dendritic cells (DC) that present tumor-associated antigens is a promising approach for immunotherapy of malignant tumors. For optimization of DC-based vaccination protocols, preclinical tumor models that mimic the clinical situation closely are highly desirable. Strong non-specific T cell activation was observed in experimental immunization of mice with syngeneic DC generated in standard FCS-supplemented culture medium. To avoid deviation of the immune response to FCS-derived antigens, a serum-free culture protocol for in vitro generation of murine DC from bone marrow progenitor cells was developed. In comparison to DC differentiated with FCS supplementation, DC generated under serum-free conditions (sfDC) have a more homogeneous phenotype with higher expression of IL-12 and the differentiation and activation markers CD11c, CD40, CD80, CD83, CD86, DEC-205, and MHC class II. Demonstration of strong uptake of protein and carbohydrate antigens and analysis of the in vivo migration behaviour of sfDC also indicated excellent APC function. Vaccination of mice with peptide-pulsed sfDC efficiently induced an antigen-specific T cell response as assessed by MHC tetramer staining, IFN-gamma ELISPOT and in vivo cytotoxicity assay. sfDC may therefore represent a valuable tool to improve active tumor immunotherapy in animal models.

  4. Borrelia burgdorferi Induces TLR2-Mediated Migration of Activated Dendritic Cells in an Ex Vivo Human Skin Model

    Science.gov (United States)

    Wagemakers, Alex; van ‘t Veer, Cornelis; Oei, Anneke; van der Pot, Wouter J.; Ahmed, Kalam; van der Poll, Tom; Geijtenbeek, Teunis B. H.; Hovius, Joppe W. R.

    2016-01-01

    Borrelia burgdorferi is transmitted into the skin of the host where it encounters and interacts with two dendritic cell (DC) subsets; Langerhans cells (LCs) and dermal DCs (DDCs). These cells recognize pathogens via pattern recognition receptors, mature and migrate out of the skin into draining lymph nodes, where they orchestrate adaptive immune responses. In order to investigate the response of skin DCs during the early immunopathogenesis of Lyme borreliosis, we injected B. burgdorferi intradermally into full-thickness human skin and studied the migration of DCs out of the skin, the activation profile and phenotype of migrated cells. We found a significant increase in the migration of LCs and DDCs in response to B. burgdorferi. Notably, migration was prevented by blocking TLR2. DCs migrated from skin inoculated with higher numbers of spirochetes expressed significantly higher levels of CD83 and produced pro-inflammatory cytokines. No difference was observed in the expression of HLA-DR, CD86, CD38, or CCR7. To conclude, we have established an ex vivo human skin model to study DC-B. burgdorferi interactions. Using this model, we have demonstrated that B. burgdorferi-induced DC migration is mediated by TLR2. Our findings underscore the utility of this model as a valuable tool to study immunity to spirochetal infections. PMID:27695100

  5. Soluble Jagged 1/Fc chimera protein induces the differentiation and maturation of bone marrow-derived dendritic cells

    Institute of Scientific and Technical Information of China (English)

    XING FeiYue; LIU Jing; YU Zhe; JI YuHua

    2008-01-01

    A soluble Jagged 1/Fc chimera protein (Jagged 1/Fc) was directly used to induce differentiation and maturation of bone marrow-derived dendritic cells (DCs) in mice in vitro. A model of inducing and am-plifying DCs in vitro was established. The effect of Jagged 1/Fc on morphology of DCs induced by both rmGM-CSF and rmlL-4 was observed under a confocal microscope. A fluorescein-labeled monoclonal antibody staining combined with flow cytometry was applied to detect the effect of Jagged 1/Fc on the expression of CD11c, MHC-Ⅱ, CD86, CD80 and CD40 molecules on the surface of DCs. The results showed that Jagged 1/Fc did not affect the morphological properties of DC differentiation induced by both rmGM-CSF and rmlL-4. But it could promote the differentiation and maturation of DCs induced by both. The effect of it was strikingly different in the expression profile of co-stimulating molecules and the morphologic properties of DCs from lipopolysaccharide (LPS). The levels of MHC-Ⅱ and CD40 molecule expression on the surface of DCs stimulated by Jagged 1/Fc were significantly lower than those stimulated by LPS, and the level of CD80 expression on the surface of DCs induced by Jagged 1/Fc was near to that induced by LPS. Jagged 1/Fc had no influence on the expression of CD86 mole-cule on the surface of DCs. Jagged 1/Fc when used alone could not maintain the growth, differentiation and maturation of DCs. All the findings indicate that Jagged 1/Fc influences the differentiation and maturation of DCs, which is not markedly similar to LPS, providing important evidence for its devel-opment and application as a novel immunosuppressant.

  6. Subgroup J avian leukosis virus infection of chicken dendritic cells induces apoptosis via the aberrant expression of microRNAs.

    Science.gov (United States)

    Liu, Di; Dai, Manman; Zhang, Xu; Cao, Weisheng; Liao, Ming

    2016-02-01

    Subgroup J avian leukosis virus (ALV-J) is an oncogenic retrovirus that causes immunosuppression and enhances susceptibility to secondary infection. The innate immune system is the first line of defense in preventing bacterial and viral infections, and dendritic cells (DCs) play important roles in innate immunity. Because bone marrow is an organ that is susceptible to ALV-J, the virus may influence the generation of bone marrow-derived DCs. In this study, DCs cultured in vitro were used to investigate the effects of ALV infection. The results revealed that ALV-J could infect these cells during the early stages of differentiation, and infection of DCs with ALV-J resulted in apoptosis. miRNA sequencing data of uninfected and infected DCs revealed 122 differentially expressed miRNAs, with 115 demonstrating upregulation after ALV-J infection and the other 7 showing significant downregulation. The miRNAs that exhibited the highest levels of upregulation may suppress nutrient processing and metabolic function. These results indicated that ALV-J infection of chicken DCs could induce apoptosis via aberrant microRNA expression. These results provide a solid foundation for the further study of epigenetic influences on ALV-J-induced immunosuppression.

  7. Avian influenza A virus PB2 promotes interferon type I inducing properties of a swine strain in porcine dendritic cells

    Energy Technology Data Exchange (ETDEWEB)

    Ocana-Macchi, Manuela; Ricklin, Meret E.; Python, Sylvie; Monika, Gsell-Albert [Institute of Virology and Immunoprophylaxis, Mittelhaeusern (Switzerland); Stech, Juergen; Stech, Olga [Friedrich-Loeffler Institut, Greifswald-Insel Riems (Germany); Summerfield, Artur, E-mail: artur.summerfield@ivi.admin.ch [Institute of Virology and Immunoprophylaxis, Mittelhaeusern (Switzerland)

    2012-05-25

    The 2009 influenza A virus (IAV) pandemic resulted from reassortment of avian, human and swine strains probably in pigs. To elucidate the role of viral genes in host adaptation regarding innate immune responses, we focussed on the effect of genes from an avian H5N1 and a porcine H1N1 IAV on infectivity and activation of porcine GM-CSF-induced dendritic cells (DC). The highest interferon type I responses were achieved by the porcine virus reassortant containing the avian polymerase gene PB2. This finding was not due to differential tropism since all viruses infected DC equally. All viruses equally induced MHC class II, but porcine H1N1 expressing the avian viral PB2 induced more prominent nuclear NF-{kappa}B translocation compared to its parent IAV. The enhanced activation of DC may be detrimental or beneficial. An over-stimulation of innate responses could result in either pronounced tissue damage or increased resistance against IAV reassortants carrying avian PB2.

  8. Development of Dendritic Cell System

    Institute of Scientific and Technical Information of China (English)

    Li Wu; Aleksandar Dakic

    2004-01-01

    The dendritic cell system contains conventional dendritic cells (DCs) and plasmacytoid pre-dendritic cells (pDCs). Both DCs and pDCs are bone marrow derived cells. Although the common functions of DCs are antigen-processing and T-lymphocyte activation, they differ in surface markers, migratory patterns, and cytokine output. These differences can determine the fate of the T cells they activate. Several subsets of mature DCs have been described in both mouse and human and the developmental processes of these specialized DC subsets have been studied extensively. The original concept that all DCs were of myeloid origin was questioned by several recent studies, which demonstrated that in addition to the DCs derived from myeloid precursors,some DCs could also be efficiently generated from lymphoid-restricted precursors. Moreover, it has been shown recently that both conventional DCs and pDCs can be generated by the Flt3 expressing hemopoietic progenitors regardless of their myeloid- or lymphoid-origin. These findings suggest an early developmental flexibility of precursors for DCs and pDCs. This review summarizes some recent observations on the development of DC system in both human and mouse.

  9. Nocardia farcinica Activates Human Dendritic Cells and Induces Secretion of Interleukin-23 (IL-23) Rather than IL-12p70

    Science.gov (United States)

    Eisenblätter, Martin; Buchal, Ariane; Gayum, Hermine; Jasny, Edith; Renner Viveros, Pablo; Ulrichs, Timo; Schneider, Thomas; Schumann, Ralf R.; Zweigner, Janine

    2012-01-01

    Studying the interaction of dendritic cells (DCs) with bacteria controlled by T-cell-mediated immune responses may reveal novel adjuvants for the induction of cellular immunity. Murine studies and the observation that nocardias infect predominantly immunosuppressed patients have suggested that these bacteria may possess an adjuvant potential. Moreover, adjuvants on the basis of the nocardial cell wall have been applied in clinical studies. Since the handling of adjuvants by DCs may determine the type of immune responses induced by a vaccine, the present study aimed at investigating the interaction of immature human monocyte-derived DCs with live or inactivated Nocardia farcinica in vitro and determining the cellular phenotypic changes as well as alterations in characteristic functions, such as phagocytosis, induction of T-cell proliferation, and cytokine secretion. Human DCs ingested N. farcinica and eradicated the bacterium intracellularly. DCs exposed to inactivated N. farcinica were activated, i.e., they developed a mature phenotype, downregulated their phagocytic capacity, and stimulated allogeneic T cells in mixed leukocyte reactions. Soluble factors were not involved in this process. To elucidate the potential adjuvant effect of N. farcinica on the induction of T-cell-mediated immune responses, we characterized the cytokines produced by nocardia-exposed DCs and detected substantial amounts of tumor necrosis factor alpha (TNF-α) and interleukin-12 p40 (IL-12p40). However, nocardia-treated DCs secreted only small amounts of IL-12p70, which were significantly smaller than the amounts of IL-23. Thus, N. farcinica activates DCs, but adjuvants based on this bacterium may have only a limited capacity to induce Th1 immune responses. PMID:22988018

  10. Monitoring the initiation and kinetics of human dendritic cell-induced polarization of autologous naive CD4+ T cells.

    Directory of Open Access Journals (Sweden)

    Tammy Oth

    Full Text Available A crucial step in generating de novo immune responses is the polarization of naive cognate CD4+ T cells by pathogen-triggered dendritic cells (DC. In the human setting, standardized DC-dependent systems are lacking to study molecular events during the initiation of a naive CD4+ T cell response. We developed a TCR-restricted assay to compare different pathogen-triggered human DC for their capacities to instruct functional differentiation of autologous, naive CD4+ T cells. We demonstrated that this methodology can be applied to compare differently matured DC in terms of kinetics, direction, and magnitude of the naive CD4+ T cell response. Furthermore, we showed the applicability of this assay to study the T cell polarizing capacity of low-frequency blood-derived DC populations directly isolated ex vivo. This methodology for addressing APC-dependent instruction of naive CD4+ T cells in a human autologous setting will provide researchers with a valuable tool to gain more insight into molecular mechanisms occurring in the early phase of T cell polarization. In addition, it may also allow the study of pharmacological agents on DC-dependent T cell polarization in the human system.

  11. Novel plant virus-based vaccine induces protective cytotoxic T-lymphocyte-mediated antiviral immunity through dendritic cell maturation.

    Science.gov (United States)

    Lacasse, Patrick; Denis, Jérôme; Lapointe, Réjean; Leclerc, Denis; Lamarre, Alain

    2008-01-01

    Currently used vaccines protect mainly through the production of neutralizing antibodies. However, antibodies confer little or no protection for a majority of chronic viral infections that require active involvement of cytotoxic T lymphocytes (CTLs). Virus-like particles (VLPs) have been shown to be efficient inducers of cell-mediated immune responses, but administration of an adjuvant is generally required. We recently reported the generation of a novel VLP system exploiting the self-assembly property of the papaya mosaic virus (PapMV) coat protein. We show here that uptake of PapMV-like particles by murine splenic dendritic cells (DCs) in vivo leads to their maturation, suggesting that they possess intrinsic adjuvant-like properties. DCs pulsed with PapMV-like particles displaying the lymphocytic choriomeningitis virus (LCMV) p33 immunodominant CTL epitope (PapMV-p33) efficiently process and cross-present the viral epitope to p33-specific transgenic T cells. Importantly, the CTL epitope is also properly processed and presented in vivo, since immunization of p33-specific T-cell receptor transgenic mice with PapMV-p33 induces the activation of large numbers of specific CTLs. C57BL/6 mice immunized with PapMV-p33 VLPs in the absence of adjuvant develop p33-specific effector CTLs that rapidly expand following LCMV challenge and protect vaccinated mice against LCMV infection in a dose-dependent manner. These results demonstrate the efficiency of this novel plant virus-based vaccination platform in inducing DC maturation leading to protective CTL responses.

  12. Organ-derived dendritic cells have differential effects on alloreactive T cells

    OpenAIRE

    Kim, Theo D.; Terwey, Theis H.; Zakrzewski, Johannes L; Suh, David; Kochman, Adam A.; Chen, Megan E.; King, Chris G.; Borsotti, Chiara; Grubin, Jeremy; Smith, Odette M.; Heller, Glenn; Liu, Chen; Murphy, George F.; Alpdogan, Onder; Marcel R. M. van den Brink

    2008-01-01

    Dendritic cells (DCs) are considered critical for the induction of graft-versus-host disease (GVHD) after bone marrow transplantation (BMT). In addition to their priming function, dendritic cells have been shown to induce organ-tropism through induction of specific homing molecules on T cells. Using adoptive transfer of CFSE-labeled cells, we first demonstrated that alloreactive T cells differentially up-regulate specific homing molecules in vivo. Host-type dendritic cells from the GVHD targe...

  13. Development of Dendritic Cell System

    Institute of Scientific and Technical Information of China (English)

    LiWu; AleksandarDakic

    2004-01-01

    The dendritic cell system contains conventional dendritic cells (DCs) and plasmacytoid pre-dendritic cells (pDCs). Both DCs and pDCs are bone marrow derived calls. Although the common functions of DCs are antigen-processing and T-lymphocyte activation, they differ in surface markers, migratory patterns, and cytokine output. These differences can determine the fate of the T cells they activate. Several subsets of mature DCs have been described in both mouse and human and the developmental processes of these specialized DC subsets have been studied extensively. The original concept that all DCs were of myeloid origin was questioned by several recent studies, which demonstrated that in addition to the DCs derived from myeloid precursors, some DCs could also be efficiently generated from lymphoid-restricted precursors. Moreover, it has been shown recently that both conventional DCs and pDCs can be generated by the Fit3 expressing hemopoietic progenitors regardless of their myeloid- or lymphoid-origin. These findings suggest an early developmental flexibility of precursors for DCs and pDCs. This review summarizes some recent observations on the development of DC system in both human and mouse. Cellular & Molecular Immunology. 2004;1(2):112-118.

  14. Unsaturated compounds induce up-regulation of CD86 on dendritic cells in the in vitro sensitization assay LCSA.

    Science.gov (United States)

    Frohwein, Thomas Armin; Sonnenburg, Anna; Zuberbier, Torsten; Stahlmann, Ralf; Schreiner, Maximilian

    2016-04-01

    Unsaturated compounds are known to cause false-positive reactions in the local lymph node assay (LLNA) but not in the guinea pig maximization test. We have tested a panel of substances (succinic acid, undecylenic acid, 1-octyn-3-ol, fumaric acid, maleic acid, linoleic acid, oleic acid, alpha-linolenic acid, squalene, and arachidonic acid) in the loose-fit coculture-based sensitization assay (LCSA) to evaluate whether unspecific activation of dendritic cells is a confounder for sensitization testing in vitro. Eight out of 10 tested substances caused significant up-regulation of CD86 on dendritic cells cocultured with keratinocytes and would have been classified as sensitizers; only succinic acid was tested negative, and squalene had to be excluded from data analysis due to poor solubility in cell culture medium. Based on human data, only undecylenic acid can be considered a true sensitizer. The true sensitizing potential of 1-octyn-3-ol is uncertain. Fumaric acid and its isomer maleic acid are not known as sensitizers, but their esters are contact allergens. A group of 18- to 20-carbon chain unsaturated fatty acids (linoleic acid, oleic acid, alpha-linolenic acid, and arachidonic acid) elicited the strongest reaction in vitro. This is possibly due to the formation of pro-inflammatory lipid mediators in the cell culture causing nonspecific activation of dendritic cells. In conclusion, both the LLNA and the LCSA seem to provide false-positive results for unsaturated fatty acids. The inclusion of T cells in dendritic cell-based in vitro sensitization assays may help to eliminate false-positive results due to nonspecific dendritic cell activation. This would lead to more accurate prediction of sensitizers, which is paramount for consumer health protection and occupational safety.

  15. The HPV16 E7 Oncoprotein Disrupts Dendritic Cell Function and Induces the Systemic Expansion of CD11b+Gr1+ Cells in a Transgenic Mouse Model

    Science.gov (United States)

    Damian-Morales, Gabriela; Serafín-Higuera, Nicolás; Moreno-Eutimio, Mario Adán; Cortés-Malagón, Enoc M.; Bonilla-Delgado, José; Rodríguez-Uribe, Genaro; Ocadiz-Delgado, Rodolfo; Lambert, Paul F.

    2016-01-01

    Objective. The aim of this study was to analyze the effects of the HPV16 E7 oncoprotein on dendritic cells (DCs) and CD11b+Gr1+ cells using the K14E7 transgenic mouse model. Materials and Methods. The morphology of DCs was analyzed in male mouse skin on epidermal sheets using immunofluorescence and confocal microscopy. Flow cytometry was used to determine the percentages of DCs and CD11b+Gr1+ cells in different tissues and to evaluate the migration of DCs. Results. In the K14E7 mouse model, the morphology of Langerhans cells and the migratory activity of dendritic cells were abnormal. An increase in CD11b+Gr1+ cells was observed in the blood and skin of K14E7 mice, and molecules related to CD11b+Gr1+ chemoattraction (MCP1 and S100A9) were upregulated. Conclusions. These data suggest that the HPV16 E7 oncoprotein impairs the function and morphology of DCs and induces the systemic accumulation of CD11b+Gr1+ cells. PMID:27478837

  16. Osteopathic manipulative therapy induces early plasma cytokine release and mobilization of a population of blood dendritic cells.

    Science.gov (United States)

    Walkowski, Stevan; Singh, Manindra; Puertas, Juan; Pate, Michelle; Goodrum, Kenneth; Benencia, Fabian

    2014-01-01

    It has been claimed that osteopathic manipulative treatment (OMT) is able to enhance the immune response of individuals. In particular, it has been reported that OMT has the capability to increase antibody titers, enhance the efficacy of vaccination, and upregulate the numbers of circulating leukocytes. Recently, it has been shown in human patients suffering chronic low back pain, that OMT is able to modify the levels of cytokines such as IL-6 and TNF-α in blood upon repeated treatment. Further, experimental animal models show that lymphatic pump techniques can induce a transient increase of cytokines in the lymphatic circulation. Taking into account all these data, we decided to investigate in healthy individuals the capacity of OMT to induce a rapid modification of the levels of cytokines and leukocytes in circulation. Human volunteers were subjected to a mixture of lymphatic and thoracic OMT, and shortly after the levels of several cytokines were evaluated by protein array technology and ELISA multiplex analysis, while the profile and activation status of circulating leukocytes was extensively evaluated by multicolor flow cytometry. In addition, the levels of nitric oxide and C-reactive protein (CRP) in plasma were determined. In this study, our results show that OMT was not able to induce a rapid modification in the levels of plasma nitrites or CRP or in the proportion or activation status of central memory, effector memory or naïve CD4 and CD8 T cells. A significant decrease in the proportion of a subpopulation of blood dendritic cells was detected in OMT patients. Significant differences were also detected in the levels of immune molecules such as IL-8, MCP-1, MIP-1α and most notably, G-CSF. Thus, OMT is able to induce a rapid change in the immunological profile of particular circulating cytokines and leukocytes.

  17. Osteopathic manipulative therapy induces early plasma cytokine release and mobilization of a population of blood dendritic cells.

    Directory of Open Access Journals (Sweden)

    Stevan Walkowski

    Full Text Available It has been claimed that osteopathic manipulative treatment (OMT is able to enhance the immune response of individuals. In particular, it has been reported that OMT has the capability to increase antibody titers, enhance the efficacy of vaccination, and upregulate the numbers of circulating leukocytes. Recently, it has been shown in human patients suffering chronic low back pain, that OMT is able to modify the levels of cytokines such as IL-6 and TNF-α in blood upon repeated treatment. Further, experimental animal models show that lymphatic pump techniques can induce a transient increase of cytokines in the lymphatic circulation. Taking into account all these data, we decided to investigate in healthy individuals the capacity of OMT to induce a rapid modification of the levels of cytokines and leukocytes in circulation. Human volunteers were subjected to a mixture of lymphatic and thoracic OMT, and shortly after the levels of several cytokines were evaluated by protein array technology and ELISA multiplex analysis, while the profile and activation status of circulating leukocytes was extensively evaluated by multicolor flow cytometry. In addition, the levels of nitric oxide and C-reactive protein (CRP in plasma were determined. In this study, our results show that OMT was not able to induce a rapid modification in the levels of plasma nitrites or CRP or in the proportion or activation status of central memory, effector memory or naïve CD4 and CD8 T cells. A significant decrease in the proportion of a subpopulation of blood dendritic cells was detected in OMT patients. Significant differences were also detected in the levels of immune molecules such as IL-8, MCP-1, MIP-1α and most notably, G-CSF. Thus, OMT is able to induce a rapid change in the immunological profile of particular circulating cytokines and leukocytes.

  18. Regulatory effect of Ganoderma lucidum polysaccharides on cytotoxic T-lymphocytes induced by dendritic cells in vitro

    Institute of Scientific and Technical Information of China (English)

    CAOLi-Zhen; LINZhi-Bin

    2003-01-01

    AIM:To study the regulatory effects of Ganoderma lucidum polysaccharides(Gl-PS)on cytotoxicity and mechanism of specific cytotoxic T-lymphocytes(CTL)induced by dendritic cells(DC)in vitro during the stage of antigen presentation.METHODS:Cultured murine bone marrow-derived DC were pulsed with P815 tumor cell lysates and co-incubated with or without various concentrations of Gl-PS(0.8,3.2,or 12.8mg/L)at the same time.P815 specific CTL were induced by spleen lymphocytes stimulated with mature DC.Non-adherent cells and culture supernatants were harvested on d 5 for analysis of specific cytotoxicity with lactate dehydrogenase(LDH)activity assay,mRNA expression of IFNγ,granzyme B with RT-PCR assay,and protein expression of IFNγ,granzyme B with ELISA or Western blot assay,respectively,RESULTS:Three concentrations of Gl-PS promoted LDH activities released into culture supernatants(P<0.01).It also increased mRNA expression of IFNγin CTL(Gl-PS 12.8mg/L vs RPMI medium 1640,P<0.05)and granzyme B in CTL(P<0.01).Protein production of IFNγin culture supernatants(P<0.05)and protein expression of granzyme B in CTL(Gl-PS 12.8mg/L vs RPMI medium 1640,P<0.05)were also augmented by Gl-PS,CONCLUSION:Gl-PS is shown to promote the cytotoxicity of specific CTL induced by DC which were pulsed with P815 tumor antigen during the stage of antigen presentation,and the mechanism of cytotoxicity is believed to be going through IFNγ and granzyme B pathways.

  19. Plasmacytoid dendritic cell role in cutaneous malignancies.

    Science.gov (United States)

    Saadeh, Dana; Kurban, Mazen; Abbas, Ossama

    2016-07-01

    Plasmacytoid dendritic cells (pDCs) correspond to a specialized dendritic cell population that exhibit plasma cell morphology, express CD4, CD123, HLA-DR, blood-derived dendritic cell antigen-2 (BDCA-2), and Toll-like receptor (TLR)7 and TLR9 within endosomal compartments. Through their production of type I interferons (IFNs) and other pro-inflammatory cytokines, pDCs provide anti-viral resistance and link the innate and adaptive immunity by controlling the function of myeloid DCs, lymphocytes, and natural killer (NK) cells. While lacking from normal skin, pDCs are usually recruited to the skin in several cutaneous pathologies where they appear to be involved in the pathogenesis of several infectious, inflammatory/autoimmune, and neoplastic entities. Among the latter group, pDCs have the potential to induce anti-tumour immunity; however, the complex interaction of pDCs with tumor cells and their micro-environment appears to contribute to immunologic tolerance. In this review, we aim at highlighting the role played by pDCs in cutaneous malignancies with special emphasis on the underlying mechanisms.

  20. Mitochondrial ATP synthase is a target for TNBS-induced protein carbonylation in XS-106 dendritic cells.

    Science.gov (United States)

    Je, Jeong Hwan; Lee, Tae Hyung; Kim, Dong Hyun; Cho, Young Hun; Lee, Ju Hee; Kim, Soo Chan; Lee, Sang-Kyou; Lee, Jaewon; Lee, Min-Geol

    2008-06-01

    ROS are produced in dendritic cells (DCs) during antigen presentation in contact hypersensitivity (CHS). As a result, ROS cause a number of nonenzymatic protein modifications, including carbonylation, which is the most widely used marker of oxidative stress. 2,4,6-Trinitrobenzene sulfonic acid (TNBS) is a well-characterized contact allergen that results in the formation of ROS. However, proteins that are carbonylated in DCs in response to TNBS have not been identified. To study ROS-dependent protein carbonylation in response to TNBS, we used the well-established mouse DC line, XS-106. We focused on the effects of TNBS on oxidation by examining selected oxidative markers. We identified TNBS-induced ROS and myeloperoxidase (MPO) proteins and demonstrated that the increase in ROS resulted in IL-12 production. The increase in oxidation was further confirmed by an oxidation-dependent increase in protein modifications, such as carbonylation. In fact, TNBS strongly induced carbonylation of mitochondrial adenosine triphosphate (ATP) synthase in XS-106 DCs, as determined by MALDI-TOF analysis and 2-D Western blotting. ROS production and protein carbonylation were confirmed in human monocyte-derived DCs (Mo-DCs). Furthermore, glutathione (GSH) decreased ROS and protein carbonylation in Mo-DCs. Carbonylation of ATP synthase in DCs may contribute to the pathophysiology of CHS.

  1. T Cell Cancer Therapy Requires CD40-CD40L Activation of Tumor Necrosis Factor and Inducible Nitric-Oxide-Synthase-Producing Dendritic Cells.

    Science.gov (United States)

    Marigo, Ilaria; Zilio, Serena; Desantis, Giacomo; Mlecnik, Bernhard; Agnellini, Andrielly H R; Ugel, Stefano; Sasso, Maria Stella; Qualls, Joseph E; Kratochvill, Franz; Zanovello, Paola; Molon, Barbara; Ries, Carola H; Runza, Valeria; Hoves, Sabine; Bilocq, Amélie M; Bindea, Gabriela; Mazza, Emilia M C; Bicciato, Silvio; Galon, Jérôme; Murray, Peter J; Bronte, Vincenzo

    2016-09-12

    Effective cancer immunotherapy requires overcoming immunosuppressive tumor microenvironments. We found that local nitric oxide (NO) production by tumor-infiltrating myeloid cells is important for adoptively transferred CD8(+) cytotoxic T cells to destroy tumors. These myeloid cells are phenotypically similar to inducible nitric oxide synthase (NOS2)- and tumor necrosis factor (TNF)-producing dendritic cells (DC), or Tip-DCs. Depletion of immunosuppressive, colony stimulating factor 1 receptor (CSF-1R)-dependent arginase 1(+) myeloid cells enhanced NO-dependent tumor killing. Tumor elimination via NOS2 required the CD40-CD40L pathway. We also uncovered a strong correlation between survival of colorectal cancer patients and NOS2, CD40, and TNF expression in their tumors. Our results identify a network of pro-tumor factors that can be targeted to boost cancer immunotherapies.

  2. Human IDO-competent, long-lived immunoregulatory dendritic cells induced by intracellular pathogen, and their fate in humanized mice

    Science.gov (United States)

    Tyagi, Rajeev K.; Miles, Brodie; Parmar, Rajesh; Garg, Neeraj K.; Dalai, Sarat K.; Baban, Babak; Cutler, Christopher W.

    2017-01-01

    Targeting of myeloid-dendritic cell receptor DC-SIGN by numerous chronic infectious agents, including Porphyromonas gingivalis, is shown to drive-differentiation of monocytes into dysfunctional mDCs. These mDCs exhibit alterations of their fine-tuned homeostatic function and contribute to dysregulated immune-responses. Here, we utilize P. gingivalis mutant strains to show that pathogen-differentiated mDCs from primary human-monocytes display anti-apoptotic profile, exhibited by elevated phosphorylated-Foxo1, phosphorylated-Akt1, and decreased Bim-expression. This results in an overall inhibition of DC-apoptosis. Direct stimulation of complex component CD40 on DCs leads to activation of Akt1, suggesting CD40 involvement in anti-apoptotic effects observed. Further, these DCs drove dampened CD8+ T-cell and Th1/Th17 effector-responses while inducing CD25+Foxp3+CD127− Tregs. In vitro Treg induction was mediated by DC expression of indoleamine 2,3-dioxygenase, and was confirmed in IDO-KO mouse model. Pathogen-infected & CMFDA-labeled MoDCs long-lasting survival was confirmed in a huMoDC reconstituted humanized mice. In conclusion, our data implicate PDDCs as an important target for resolution of chronic infection. PMID:28198424

  3. Proapoptotic chemotherapeutic drugs induce noncanonical processing and release of IL-1β via caspase-8 in dendritic cells.

    Science.gov (United States)

    Antonopoulos, Christina; El Sanadi, Caroline; Kaiser, William J; Mocarski, Edward S; Dubyak, George R

    2013-11-01

    The identification of noncanonical (caspase-1-independent) pathways for IL-1β production has unveiled an intricate interplay between inflammatory and death-inducing signaling platforms. We found a heretofore unappreciated role for caspase-8 as a major pathway for IL-1β processing and release in murine bone marrow-derived dendritic cells (BMDC) costimulated with TLR4 agonists and proapoptotic chemotherapeutic agents such as doxorubicin (Dox) or staurosporine (STS). The ability of Dox to stimulate release of mature (17-kDa) IL-1β was nearly equivalent in wild-type (WT) BMDC, Casp1(-/-)Casp11(-/-) BMDC, WT BMDC treated with the caspase-1 inhibitor YVAD, and BMDC lacking the inflammasome regulators ASC, NLRP3, or NLRC4. Notably, Dox-induced production of mature IL-1β was temporally correlated with caspase-8 activation in WT cells and greatly suppressed in Casp8(-/-)Rip3(-/-) or Trif(-/-) BMDC, as well as in WT BMDC treated with the caspase-8 inhibitor, IETD. Similarly, STS stimulated robust IL-1β processing and release in Casp1(-/-)Casp11(-/-) BMDC that was IETD sensitive. These data suggest that TLR4 induces assembly of caspase-8-based signaling complexes that become licensed as IL-1β-converting enzymes in response to Dox and STS. The responses were temporally correlated with downregulation of cellular inhibitor of apoptosis protein 1, suggesting suppressive roles for this and likely other inhibitor of apoptosis proteins on the stability and/or proteolytic activity of the caspase-8 platforms. Thus, proapoptotic chemotherapeutic agents stimulate the caspase-8-mediated processing and release of IL-1β, implicating direct effects of such drugs on a noncanonical inflammatory cascade that may modulate immune responses in tumor microenvironments.

  4. Antibodies to P-selectin glycoprotein ligand-1 block dendritic cell-mediated enterovirus 71 transmission and prevent virus-induced cells death.

    Science.gov (United States)

    Ren, Xiao-Xin; Li, Chuan; Xiong, Si-Dong; Huang, Zhong; Wang, Jian-Hua; Wang, Hai-Bo

    2015-01-01

    P-selectin glycoprotein ligand-1 (PSGL-1) has been proved to serve as the functional receptor for enterovirus 71 (EV71). We found the abundant expression of PSGL-1 on monocyte-derived dendritic cells (MDDCs). However, we have previously demonstrated that MDDCs did not support efficient replication of EV71. Dendritic cells (DCs) have been described to be subverted by various viruses including EV71 for viral dissemination, we thus explore the potential contribution of PSGL-1 on DC-mediated EV71 transmission. We found that the cell-surface-expressing PSGL-1 on MDDCs mediated EV71 binding, and intriguingly, these loaded-viruses on MDDCs could be transferred to encountered target cells; Prior-treatment with PSGL-1 antibodies or interference with PSGL-1 expression diminished MDDC-mediated EV71 transfer and rescued virus-induced cell death. Our data uncover a novel role of PSGL-1 in DC-mediated EV71 spread, and provide an insight into blocking primary EV71 infection.

  5. Excretory/secretory-products of Echinococcus multilocularis larvae induce apoptosis and tolerogenic properties in dendritic cells in vitro.

    Directory of Open Access Journals (Sweden)

    Justin Komguep Nono

    Full Text Available BACKGROUND: Alveolar echinococcosis, caused by Echinococcus multilocularis larvae, is a chronic disease associated with considerable modulation of the host immune response. Dendritic cells (DC are key effectors in shaping the immune response and among the first cells encountered by the parasite during an infection. Although it is assumed that E.multilocularis, by excretory/secretory (E/S-products, specifically affects DC to deviate immune responses, little information is available on the molecular nature of respective E/S-products and their mode of action. METHODOLOGY/PRINCIPAL FINDINGS: We established cultivation systems for exposing DC to live material from early (oncosphere, chronic (metacestode and late (protoscolex infectious stages. When co-incubated with Echinococcus primary cells, representing the invading oncosphere, or metacestode vesicles, a significant proportion of DC underwent apoptosis and the surviving DC failed to mature. In contrast, DC exposed to protoscoleces upregulated maturation markers and did not undergo apoptosis. After pre-incubation with primary cells and metacestode vesicles, DC showed a strongly impaired ability to be activated by the TLR ligand LPS, which was not observed in DC pre-treated with protoscolex E/S-products. While none of the larvae induced the secretion of pro-inflammatory IL-12p70, the production of immunosuppressive IL-10 was elevated in response to primary cell E/S-products. Finally, upon incubation with DC and naïve T-cells, E/S-products from metacestode vesicles led to a significant expansion of Foxp3+ T cells in vitro. CONCLUSIONS: This is the first report on the induction of apoptosis in DC by cestode E/S-products. Our data indicate that the early infective stage of E. multilocularis is a strong inducer of tolerance in DC, which is most probably important for generating an immunosuppressive environment at an infection phase in which the parasite is highly vulnerable to host attacks. The

  6. Dendritic Cells, New Tools for Vaccination

    Science.gov (United States)

    2003-01-01

    Review Dendritic cells , new tools for vaccination Jesus Colino, Clifford M. Snapper * Department of Pathology, Uniformed Services University of the...2003 Éditions scientifiques et médicales Elsevier SAS. All rights reserved. Keywords: Vaccines; Immunotherapy; Dendritic cells 1. Introduction During...DATE 2003 2. REPORT TYPE 3. DATES COVERED 00-00-2003 to 00-00-2003 4. TITLE AND SUBTITLE Dendritic cells , new tools for vaccination 5a

  7. Neoplasms derived from plasmacytoid dendritic cells.

    Science.gov (United States)

    Facchetti, Fabio; Cigognetti, Marta; Fisogni, Simona; Rossi, Giuseppe; Lonardi, Silvia; Vermi, William

    2016-02-01

    Plasmacytoid dendritic cell neoplasms manifest in two clinically and pathologically distinct forms. The first variant is represented by nodular aggregates of clonally expanded plasmacytoid dendritic cells found in lymph nodes, skin, and bone marrow ('Mature plasmacytoid dendritic cells proliferation associated with myeloid neoplasms'). This entity is rare, although likely underestimated in incidence, and affects predominantly males. Almost invariably, it is associated with a myeloid neoplasm such as chronic myelomonocytic leukemia or other myeloid proliferations with monocytic differentiation. The concurrent myeloid neoplasm dominates the clinical pictures and guides treatment. The prognosis is usually dismal, but reflects the evolution of the associated myeloid leukemia rather than progressive expansion of plasmacytoid dendritic cells. A second form of plasmacytoid dendritic cells tumor has been recently reported and described as 'blastic plasmacytoid dendritic cell neoplasm'. In this tumor, which is characterized by a distinctive cutaneous and bone marrow tropism, proliferating cells derive from immediate CD4(+)CD56(+) precursors of plasmacytoid dendritic cells. The diagnosis of this form can be easily accomplished by immunohistochemistry, using a panel of plasmacytoid dendritic cells markers. The clinical course of blastic plasmacytoid dendritic cell neoplasm is characterized by a rapid progression to systemic disease via hematogenous dissemination. The genomic landscape of this entity is currently under intense investigation. Recurrent somatic mutations have been uncovered in different genes, a finding that may open important perspectives for precision medicine also for this rare, but highly aggressive leukemia.

  8. The therapeutic T-cell response induced by tumor delivery of TNF and melphalan is dependent on early triggering of natural killer and dendritic cells.

    Science.gov (United States)

    Balza, Enrica; Zanellato, Silvia; Poggi, Alessandro; Reverberi, Daniele; Rubartelli, Anna; Mortara, Lorenzo

    2017-04-01

    The fusion protein L19mTNF (mouse TNF and human antibody fragment L19 directed to fibronectin extra domain B) selectively targets the tumor vasculature, and in combination with melphalan induces a long-lasting T-cell therapeutic response and immune memory in murine models. Increasing evidence suggests that natural killer (NK) cells act to promote effective T-cell-based antitumor responses. We have analyzed the role of NK cells and dendritic cells (DCs) on two different murine tumor models: WEHI-164 fibrosarcoma and C51 colon carcinoma, in which the combined treatment induces high and low rejection rates, respectively. In vivo NK-cell depletion strongly reduced the rejection of WEHI-164 fibrosarcoma and correlated with a decrease in mature DCs, CD4(+) , and CD8(+) T cells in the tumor-draining LNs and mature DCs and CD4(+) T cells in the tumor 40 h after initiation of the therapy. NK-cell depletion also resulted in the impairment of the stimulatory capability of DCs derived from tumor-draining LNs of WEHI-164-treated mice. Moreover, a significant reduction of M2-type infiltrating macrophages was detected in both tumors undergoing therapy. These results suggest that the efficacy of L19mTNF/melphalan therapy is strongly related to the early activation of NK cells and DCs, which are necessary for an effective T-cell response. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Rebamipide induces dendritic cell recruitment to N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-exposed rat gastric mucosa based on IL-1β upregulation.

    Science.gov (United States)

    Yamamichi, Nobutake; Oka, Masashi; Inada, Ken-ichi; Konno-Shimizu, Maki; Kageyama-Yahara, Natsuko; Tamai, Hideyuki; Kato, Jun; Fujishiro, Mitsuhiro; Kodashima, Shinya; Niimi, Keiko; Ono, Satoshi; Tsutsumi, Yutaka; Ichinose, Masao; Koike, Kazuhiko

    2012-07-20

    Rebamipide is usually used for mucosal protection, healing of gastric ulcers, treatment of gastritis, etc., but its effects on gastric malignancy have not been elucidated. Using Lewis and Buffalo rat strains treated with peroral administration of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), we evaluated the effect of rebamipide on the induction of tumor-suppressive dendritic cells, which are known to be heterogeneous antigen-presenting cells of bone marrow origin and are critical for the initiation of primary T-cell responses. Using CD68 as a marker for dendritic cells, the stomach pyloric mucosae of Lewis and Buffalo rats were immunohistochemically analyzed in the presence or absence of rebamipide and MNNG. After a 14-day treatment of rebamipide alone, no significant change in number of CD68-expressing cells was detected in either rat strain. However, after concurrent exposure to MNNG for 14 days, treatment with rebamipide slightly increased CD68-positive cells in the Lewis strain, and significantly increased them in the Buffalo strain. Analysis of two chemotactic factors of dendritic cells, IL-1β and TNF-α, in the gastric cancer cells showed that expression of IL-1β, but not TNF-α, was induced by rebamipide in a dose-dependent manner. A luciferase promoter assay using gastric SH-10-TC cells demonstrated that an element mediating rebamipide action exists in the IL-1β gene promoter region. In conclusion, rebamipide has potential tumor-suppressive effects on gastric tumorigenesis via the recruitment of dendritic cells, based on the upregulation of the IL-1β gene in gastric epithelial cells. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Efficient loading of dendritic cells following cryo and radiofrequency ablation in combination with immune modulation induces anti-tumour immunity

    Science.gov (United States)

    den Brok, M H M G M; Sutmuller, R P M; Nierkens, S; Bennink, E J; Frielink, C; Toonen, L W J; Boerman, O C; Figdor, C G; Ruers, T J M; Adema, G J

    2006-01-01

    Dendritic cells (DC) are professional antigen-presenting cells that play a pivotal role in the induction of immunity. Ex vivo-generated, tumour antigen-loaded mature DC are currently exploited as cancer vaccines in clinical studies. However, antigen loading and maturation of DC directly in vivo would greatly facilitate the application of DC-based vaccines. We formerly showed in murine models that radiofrequency-mediated tumour destruction can provide an antigen source for the in vivo induction of anti-tumour immunity, and we explored the role of DC herein. In this paper we evaluate radiofrequency and cryo ablation for their ability to provide an antigen source for DC and compare this with an ex vivo-loaded DC vaccine. The data obtained with model antigens demonstrate that upon tumour destruction by radiofrequency ablation, up to 7% of the total draining lymph node (LN) DC contained antigen, whereas only few DC from the conventional vaccine reached the LN. Interestingly, following cryo ablation the amount of antigen-loaded DC is almost doubled. Analysis of surface markers revealed that both destruction methods were able to induce DC maturation. Finally, we show that in situ tumour ablation can be efficiently combined with immune modulation by anti-CTLA-4 antibodies or regulatory T-cell depletion. These combination treatments protected mice from the outgrowth of tumour challenges, and led to in vivo enhancement of tumour-specific T-cell numbers, which produced more IFN-γ upon activation. Therefore, in situ tumour destruction in combination with immune modulation creates a unique, ‘in situ DC-vaccine' that is readily applicable in the clinic without prior knowledge of tumour antigens. PMID:16953240

  11. Maturation of human dendritic cells by monocyte-conditioned medium is dependent upon trace amounts of lipopolysaccharide inducing tumour necrosis factor alpha

    DEFF Research Database (Denmark)

    Nersting, Jacob; Svenson, Morten; Andersen, Vagn

    2003-01-01

    We investigated the ability of monocyte-conditioned medium (MCM), generated by monocytes cultured on plastic-immobilised immunoglobulin, to stimulate maturation of human monocyte-derived dendritic cells (DC). Earlier reports suggest that MCM is a strong inducer of irreversible DC maturation......-stimulatory potency of LPS. Maturation by this procedure is mediated mainly by tumour necrosis factor alpha secreted from monocytes during the medium-conditioning period....

  12. Pro-apoptotic Chemotherapeutic Drugs Induce Non-canonical Processing and Release of IL-1β via Caspase-8 in Dendritic Cells#

    OpenAIRE

    Antonopoulos, Christina; El Sanadi, Caroline; Kaiser, William J.; Mocarski, Edward S.; Dubyak, George R.

    2013-01-01

    The identification of non-canonical (caspase-1 independent) pathways for IL-1β production has unveiled an intricate interplay between inflammatory and death-inducing signaling platforms. We found a heretofore unappreciated role for caspase-8 as a major pathway for IL-1β processing and release in murine bone marrow-derived dendritic cells (BMDC) co-stimulated with TLR4 agonists and pro-apoptotic chemotherapeutic agents such as doxorubicin (Dox) or staurosporine (STS). The ability of Dox to sti...

  13. Leishmania mexicana promastigotes down regulate JNK and p-38 MAPK activation: Role in the inhibition of camptothecin-induced apoptosis of monocyte-derived dendritic cells.

    Science.gov (United States)

    Rodríguez-González, Jorge; Wilkins-Rodríguez, Arturo; Argueta-Donohué, Jesús; Aguirre-García, Magdalena; Gutiérrez-Kobeh, Laila

    2016-04-01

    Dendritic cells (DC) are one of the principal host cells of the obligate intracellular parasite Leishmania. Inhibition of host cell apoptosis is a strategy employed by multiple pathogens to ensure their survival in the infected cell. We have previously shown that the infection of monocyte-derived dendritic cells (moDC) with Leishmania mexicana inhibits campthotecin-induced apoptosis. Nevertheless, the mechanisms involved in the inhibition of apoptosis of dendritic cells by Leishmania have not been established. Mitogen-activated protein kinases (MAPK) are key participants in the process of apoptosis and different species of Leishmania have been shown to regulate these kinases. In the present study, we analyzed the effect of L. mexicana promastigotes in the activation of JNK and p38 MAP kinase and their participation in the inhibition of apoptosis. The infection of moDC with L. mexicana promastigotes diminished significantly the phosphorylation of the MAP kinases JNK and p38. The inhibition of both kinases diminished DNA fragmentation, but in a major extent was the reduction of DNA fragmentation when JNK was inhibited. The capacity of L. mexicana promastigotes to diminish MAP kinases activation is probably one of the strategies employed to delay apoptosis induction in the infected moDC and may have implications for Leishmania pathogenesis by favoring the invasion of its host and the persistence of the parasite in the infected cells.

  14. Pulmonary infections in swine induce altered porcine surfactant protein D expression and localization to dendritic cells in bronchial-associated lymphoid tissue

    DEFF Research Database (Denmark)

    Sørensen, C.M.; Holmskov, U.; Aalbæk, B.;

    2005-01-01

    Surfactant protein D (SP-D) is a pattern-recognition molecule of the innate immune system that recognizes various microbial surface-specific carbohydrate and lipid patterns. In vitro data has suggested that this binding may lead to increased microbial association with macrophages and dendritic...... among pSP-D, pathogens, phagocytic cells and dendritic cells. Lung tissue was collected from experimental and natural bronchopneumonias caused by Actinobacillus pleuropneumoniae or Staphylococcus aureus, and from embolic and diffuse interstitial pneumonia, caused by Staph. aureus or Arcanobacterium......SP-D through the specialized M cells overlying (BALT). In conclusion, we have shown that pSP-D expression in the lung surfactant is induced by bacterial infection by an aerogenous route rather than by a haematogenous route, and that the protein interacts specifically with alveolar macrophages...

  15. Reduction of conventional dendritic cells during Plasmodium infection is dependent on activation induced cell death by type I and II interferons.

    Science.gov (United States)

    Tamura, Takahiko; Kimura, Kazumi; Yui, Katsuyuki; Yoshida, Shigeto

    2015-12-01

    Dendritic cells (DCs) play critical roles in innate and adaptive immunity and in pathogenesis during the blood stage of malaria infection. The mechanisms underlying DC homeostasis during malaria infection are not well understood. In this study, the numbers of conventional DCs (cDCs) and plasmacytoid DCs (pDCs) in the spleens after lethal rodent malaria infection were examined, and were found to be significantly reduced. Concomitant with up-regulation of maturation-associated molecules, activation of caspase-3 was significantly increased, suggesting induction of cell death. Studies using neutralizing antibody and gene-deficient mice showed that type I and II interferons were critically involved in activation induced cell death of cDCs during malaria infection. These results demonstrate that DCs rapidly disappeared following IFN-mediated DC activation, and that homeostasis of DCs was significantly impaired during malaria infection.

  16. Toll-like receptor activation enhances cell-mediated immunity induced by an antibody vaccine targeting human dendritic cells

    Directory of Open Access Journals (Sweden)

    Berger Marc A

    2007-01-01

    Full Text Available Abstract Previously, we have successfully targeted the mannose receptor (MR expressed on monocyte-derived dendritic cells (DCs using a fully human MR-specific antibody, B11, as a vehicle to deliver whole protein tumor antigens such as the human chorionic gonadotropin hormone (hCGβ. Since MRs play a role in bridging innate immunity with adaptive immunity we have explored several toll-like receptor (TLR-specific ligands that may synergize with MR targeting and be applicable as adjuvants in the clinic. We demonstrate that antigen-specific helper and cytolytic T cells from both healthy donors and cancer patients were effectively primed with B11-hCGβ-treated autologous DCs when a combination of one or several TLR ligands is used. Specifically, concomitant signaling of DCs via TLR3 with dsRNA (poly I:C and DC TLR 7/8 with Resiquimod (R-848, respectively, elicited efficient antigen presentation-mediated by MR-targeting. We demonstrate that MR and TLRs contribute towards maturation and activation of DCs by a mechanism that may be driven by a combination of adjuvant and antibody vaccines that specifically deliver antigenic targets to DCs.

  17. Transcriptional profiling of dendritic cells matured in different osmolarities

    Directory of Open Access Journals (Sweden)

    Federica Chessa

    2016-03-01

    Full Text Available Tissue-specific microenvironments shape the fate of mononuclear phagocytes [1–3]. Interstitial osmolarity is a tissue biophysical parameter which considerably modulates the phenotype and function of dendritic cells [4]. In the present report we provide a detailed description of our experimental workflow and bioinformatic analysis applied to our gene expression dataset (GSE72174, aiming to investigate the influence of different osmolarity conditions on the gene expression signature of bone marrow-derived dendritic cells. We established a cell culture system involving murine bone marrow cells, cultured under different NaCl-induced osmolarity conditions in the presence of the dendritic cell growth factor GM-CSF. Gene expression analysis was applied to mature dendritic cells (day 7 developed in different osmolarities, with and without prior stimulation with the TLR2/4 ligand LPS.

  18. Dendritic cells modified by vitamin D

    DEFF Research Database (Denmark)

    Pedersen, Ayako Wakatsuki; Claesson, Mogens Helweg; Zocca, Mai-Britt

    2011-01-01

    Dendritic cells (DCs), the most potent antigen-presenting cells of the immune system, express nuclear receptors for 1,25-dihydroxyvitamin D(3) (VD3) and they are one of its main targets. In the presence of VD3, DCs differentiate into a phenotype that resembles semimature DCs, with reduced T cell ...... and the optimal frequency, dose, and route of DC administration to achieve therapeutic effects in humans, adoptive VD3-DC transfer represents one of the most promising approaches to future treatment of autoimmune diseases.......Dendritic cells (DCs), the most potent antigen-presenting cells of the immune system, express nuclear receptors for 1,25-dihydroxyvitamin D(3) (VD3) and they are one of its main targets. In the presence of VD3, DCs differentiate into a phenotype that resembles semimature DCs, with reduced T cell...... costimulatory molecules and hampered IL-12 production. These VD3-modulated DCs induce T cell tolerance in vitro using multiple mechanisms such as rendering T cells anergic, dampening of Th1 responses, and recruiting and differentiating regulatory T cells. Due to their ability to specifically target pathological...

  19. Lipoxin A4 negatively regulates lipopolysaccharide-induced differentiation of RAW264.7 murine macrophages into dendritic-like cells

    Institute of Scientific and Technical Information of China (English)

    ZHANG Li; WU Ping; JIN Sheng-wei; YUAN Ping; WAN Jing-yuan; ZHOU Xiao-yan; XIONG Wei; FANG Feng; YE Du-yun

    2007-01-01

    Background Lipoxins (LXs), endogenous anti-inflammatory and pro-resolving eicosanoids generated during various inflammatory conditions, have novel immunomodulatory properties. Because dendritic cells (DCs) play crucial roles in the initiation and maintenance of immune response, we determined whether LXs could modulate the maturation process of DCs and investigated the effects of lipoxin A4 (LXA4) on lipopolysaccharide (LPS)-induced differentiation of RAW264.7cells into dendritic-like cells.Methods RAW264.7 cells were cultured in vitro with 1 μg/ml LPS in the absence or presence of LXA4 for 24 hours, and cellular surface markers (MHC-Ⅱ, CD80 (B7-1), CD86(B7-2)) were measured by flow cytometry (FCM). Mixed lymphocyte reaction was performed to evaluate the allostimulatory activity. Cytoplastic IκB degradation and nuclear factor kappa B (NF-κB) translocation were detected by Western blotting. Luciferase reporter plasmid was transiently transfected into RAW264.7 cells, and luciferase activity was determined to measure the transcriptional activity of NF-κB.Results LXA4 reduced the ratio of LPS-treated RAW264.7 cells to DCs with morphological characteristics and inhibited the expression of MHC Ⅱ. LPS-induced up-regulation of CD86 was moderately suppressed by LXA4 but no obvious change of CD80 was observed. Moreover, LXA4 weakened the allostimulatory activity of LPS-treated RAW264.7 cells.These alterations of LPS+LXA4-treated cells were associated with a marked inhibition of IκB degradation, NF-κB translocation and then the transcriptional activity of NF-κB.Conclusions LXA4 negatively regulates LPS-induced differentiation of RAW264.7 cells into dendritic-like cells.This activity reveals an undescribed mechanism of LXA4 to prevent excessive and sustained immune reaction by regulating maturation of DCs.

  20. Fate mapping of dendritic cells

    Directory of Open Access Journals (Sweden)

    Barbara Ursula Schraml

    2015-05-01

    Full Text Available Dendritic cells (DCs are a heterogeneous group of mononuclear phagocytes with versatile roles in immunity. They are classified predominantly based on phenotypic and functional properties, namely their stellate morphology, expression of the integrin CD11c and major histocompatibility class II molecules, as well as their superior capacity to migrate to secondary lymphoid organs and stimulate naïve T cells. However, these attributes are not exclusive to DCs and often change within inflammatory or infectious environments. This led to debates over cell identification and questioned even the mere existence of DCs as distinct leukocyte lineage. Here, we review experimental approaches taken to fate map DCs and discuss how these have shaped our understanding of DC ontogeny and lineage affiliation. Considering the ontogenetic properties of DCs will help to overcome the inherent shortcomings of purely phenotypic- and function-based approaches to cell definition and will yield a more robust way of DC classification.

  1. Lactobacillus curvatus WiKim38 isolated from kimchi induces IL-10 production in dendritic cells and alleviates DSS-induced colitis in mice.

    Science.gov (United States)

    Jo, Sung-Gang; Noh, Eui-Jeong; Lee, Jun-Young; Kim, Green; Choi, Joo-Hee; Lee, Mo-Eun; Song, Jung-Hee; Chang, Ji-Yoon; Park, Jong-Hwan

    2016-07-01

    Probiotics such as lactobacilli and bifidobacteria have healthpromoting effects by immune modulation. In the present study, we examined the immunomodulatory properties of Lactobacillus curvatus WiKim38, which was newly isolated from baechu (Chinese cabbage) kimchi. The ability of L. curvatus WiKim38 to induce cytokine production in bone marrow-derived dendritic cells (BMDCs) was determined by enzyme-linked immunosorbent assay. To evaluate the molecular mechanisms underlying L. curvatus Wikim38-mediated IL-10 production, Western blot analyses and inhibitor assays were performed. Moreover, the in vivo anti-inflammatory effects of L. curvatus WiKim38 were examined in a dextran sodium sulfate (DSS)-induced colitis mouse model. L. curvatus WiKim38 induced significantly higher levels of IL-10 in BMDCs compared with that induced by LPS. NF-κB and ERK were activated by L. curvatus WiKim38, and an inhibitor assay revealed that these pathways were required for L. curvatus WiKim38-induced production of IL-10 in BMDCs. An in vivo experiment showed that oral administration of L. curvatus WiKim38 increased the survival rate of mice with DSS-induced colitis and improved clinical signs and histopathological severity in colon tissues. Taken together, these results indicate that L. curvatus Wikim38 may have health-promoting effects via immune modulation, and may thus be applicable for therapy of various inflammatory diseases.

  2. Glycans from Fasciola hepatica Modulate the Host Immune Response and TLR-Induced Maturation of Dendritic Cells.

    Science.gov (United States)

    Rodríguez, Ernesto; Noya, Verónica; Cervi, Laura; Chiribao, María Laura; Brossard, Natalie; Chiale, Carolina; Carmona, Carlos; Giacomini, Cecilia; Freire, Teresa

    2015-12-01

    Helminths express various carbohydrate-containing glycoconjugates on their surface, and they release glycan-rich excretion/secretion products that can be very important in their life cycles, infection and pathology. Recent evidence suggests that parasite glycoconjugates could play a role in the evasion of the immune response, leading to a modified Th2-polarized immune response that favors parasite survival in the host. Nevertheless, there is limited information about the nature or function of glycans produced by the trematode Fasciola hepatica, the causative agent of fasciolosis. In this paper, we investigate whether glycosylated molecules from F. hepatica participate in the modulation of host immunity. We also focus on dendritic cells, since they are an important target of immune-modulation by helminths, affecting their activity or function. Our results indicate that glycans from F. hepatica promote the production of IL-4 and IL-10, suppressing IFNγ production. During infection, this parasite is able to induce a semi-mature phenotype of DCs expressing low levels of MHCII and secrete IL-10. Furthermore, we show that parasite glycoconjugates mediate the modulation of LPS-induced maturation of DCs since their oxidation restores the capacity of LPS-treated DCs to secrete high levels of the pro-inflammatory cytokines IL-6 and IL-12/23p40 and low levels of the anti-inflammatory cytokine IL-10. Inhibition assays using carbohydrates suggest that the immune-modulation is mediated, at least in part, by the recognition of a mannose specific-CLR that signals by recruiting the phosphatase Php2. The results presented here contribute to the understanding of the role of parasite glycosylated molecules in the modulation of the host immunity and might be useful in the design of vaccines against fasciolosis.

  3. Glycans from Fasciola hepatica Modulate the Host Immune Response and TLR-Induced Maturation of Dendritic Cells

    Science.gov (United States)

    Rodríguez, Ernesto; Noya, Verónica; Cervi, Laura; Chiribao, María Laura; Brossard, Natalie; Chiale, Carolina; Carmona, Carlos; Giacomini, Cecilia; Freire, Teresa

    2015-01-01

    Helminths express various carbohydrate-containing glycoconjugates on their surface, and they release glycan-rich excretion/secretion products that can be very important in their life cycles, infection and pathology. Recent evidence suggests that parasite glycoconjugates could play a role in the evasion of the immune response, leading to a modified Th2-polarized immune response that favors parasite survival in the host. Nevertheless, there is limited information about the nature or function of glycans produced by the trematode Fasciola hepatica, the causative agent of fasciolosis. In this paper, we investigate whether glycosylated molecules from F. hepatica participate in the modulation of host immunity. We also focus on dendritic cells, since they are an important target of immune-modulation by helminths, affecting their activity or function. Our results indicate that glycans from F. hepatica promote the production of IL-4 and IL-10, suppressing IFNγ production. During infection, this parasite is able to induce a semi-mature phenotype of DCs expressing low levels of MHCII and secrete IL-10. Furthermore, we show that parasite glycoconjugates mediate the modulation of LPS-induced maturation of DCs since their oxidation restores the capacity of LPS-treated DCs to secrete high levels of the pro-inflammatory cytokines IL-6 and IL-12/23p40 and low levels of the anti-inflammatory cytokine IL-10. Inhibition assays using carbohydrates suggest that the immune-modulation is mediated, at least in part, by the recognition of a mannose specific-CLR that signals by recruiting the phosphatase Php2. The results presented here contribute to the understanding of the role of parasite glycosylated molecules in the modulation of the host immunity and might be useful in the design of vaccines against fasciolosis. PMID:26720149

  4. Bifidobacterium bifidum Actively Changes the Gene Expression Profile Induced by Lactobacillus acidophilus in Murine Dendritic Cells

    DEFF Research Database (Denmark)

    Weiss, Gudrun Margarethe; Rasmussen, Simon; Fink, Lisbeth Nielsen

    2010-01-01

    cytokine IL-12 in DC, whereas bifidobacteria do not induce IL-12 but inhibit the IL-12 production induced by lactobacilli. In the present study, genome-wide microarrays were used to investigate the gene expression pattern of murine DC stimulated with Lactobacillus acidophilus NCFM and Bifidobacterium...

  5. Targeting the gut vascular endothelium induces gut effector CD8 T cell responses via cross-presentation by dendritic cells.

    Science.gov (United States)

    Bourges, Dorothee; Zhan, Yifan; Brady, Jamie L; Braley, Hal; Caminschi, Irina; Prato, Sandro; Villadangos, José A; Lew, Andrew M

    2007-11-01

    Systemic delivery of Ag usually induces poor mucosal immunity. To improve the CD8 T cell response at mucosal sites, we targeted the Ag to MAdCAM-1, a mucosal addressin cell adhesion molecule expressed mainly by high endothelial venules (HEV) in mesenteric lymph nodes (MLN) and Peyer's patches of gut-associated lymphoid tissue. When chemical conjugates of anti-MAdCAM-1 Ab and model Ag OVA were injected i.v., a greatly enhanced proliferative response of Ag-specific OT-I CD8 T cells was detected in MLN. This was preceded by prolonged accumulation, up to 2 wk, of the anti-MAdCAM OVA conjugate on HEV of Peyer's patches and MLN. In contrast, nontargeted OVA conjugate was very inefficient in inducing OT-I CD8 T cell proliferation in MLN and required at least 20-fold more Ag to induce a comparable response. In addition, MAdCAM targeting elicits an endogenous OVA-specific CD8 T cell response, evident by IFN-gamma production and target killing. Induced response offers protection against an OVA-expressing B cell lymphoma. We propose that the augmentation of gut CD8 T cell responses by MAdCAM targeting is due to both accumulation of Ag in the HEV and conversion of a soluble Ag to a cell-associated one, allowing cross-presentation by DCs.

  6. Dendritic cells engineered to express defined allo-HLA peptide complexes induce antigen-specific cytotoxic T cells efficiently killing tumour cells

    DEFF Research Database (Denmark)

    Stronen, E; Abrahamsen, I W; Gaudernack, G;

    2009-01-01

    presented by a non-self human leucocyte antigen (HLA) molecule and transferred to cancer patients expressing that HLA molecule. Obtaining allo-restricted CTL of high-avidity and low cross-reactivity has, however, proven difficult. Here, we show that dendritic cells transfected with mRNA encoding HLA-A*0201...... and efficiently killed HLA-A*0201(+) melanoma cells, whilst sparing HLA-A*0201(+) B-cells. Allo-restricted CTL specific for peptides from the leukaemia-associated antigens CD33 and CD19 were obtained with comparable efficiency. Collectively, the results show that dendritic cells engineered to express defined allo......Most tumour-associated antigens (TAA) are non-mutated self-antigens. The peripheral T cell repertoire is devoid of high-avidity TAA-specific cytotoxic T lymphocytes (CTL) due to self-tolerance. As tolerance is major histocompatibility complex-restricted, T cells may be immunized against TAA...

  7. Probiotic Bio-Three induces Th1 and anti-inflammatory effects in PBMC and dendritic cells

    Institute of Scientific and Technical Information of China (English)

    Man-Chin; Hua; Tzou-Yien; Lin; Chien-Chang; Chen

    2010-01-01

    AIM:To investigate the immune response of peripheral blood mononuclear cells(PBMCs)and dendritic cells (DCs)that were stimulated by probiotic preparations. METHODS:PBMCs were isolated,cultured,and stimulated with Bio-Three(a mixture of Bacillus mesentericus, Clostridium butyricum and Enterococcus faecalis;105, 10 6 and 10 7 CFU/mL for 24 h).Cytokine production of (1)circulating PBMCs;(2)PBMCs stimulated by probiotic preparation;(3)monocyte-derived DCs;and(4)DC andT cell co-culture was determined by enzyme-l...

  8. Influenza Virus–induced Dendritic Cell Maturation Is Associated with the Induction of Strong T Cell Immunity to a Coadministered, Normally Nonimmunogenic Protein

    Science.gov (United States)

    Brimnes, Marie K.; Bonifaz, Laura; Steinman, Ralph M.; Moran, Thomas M.

    2003-01-01

    We evaluated the proposal that during microbial infection, dendritic cells (DCs) undergo maturation and present a mixture of peptides derived from the microbe as well as harmless environmental antigens. Mice were exposed to an aerosol of endotoxin free ovalbumin (OVA) in the absence or presence of influenza virus. In its absence, OVA failed to induce B and T cell responses and even tolerized, but with influenza, OVA-specific antibodies and CD8+ cytolytic T lymphocytes developed. With or without infection, OVA was presented selectively in the draining mediastinal lymph nodes, as assessed by the comparable proliferation of infused, CD8+ and CD4+, TCR transgenic T cells. In the absence of influenza, these OVA-specific T cells produced little IL-2, IL-4, IL-10, and IFN-γ, but with infection, both CD4+ and CD8+ T cells made high levels of IL-2 and IFN-γ. The OVA plus influenza-treated mice also showed accelerated recovery to a challenge with recombinant vaccinia OVA virus. CD11c+ DCs from the mediastinal lymph nodes of infected mice selectively stimulated both OVA- and influenza-specific T cells and underwent maturation, with higher levels of MHC class II, CD80, and CD86 molecules. The relatively slow (2–3 d) kinetics of maturation correlated closely to the time at which OVA inhalation elicited specific antibodies. Therefore respiratory infection can induce DC maturation and simultaneously B and T cell immunity to an innocuous antigen inhaled concurrently. PMID:12847140

  9. Helminth antigens enable CpG-activated dendritic cells to inhibit the symptoms of collagen-induced arthritis through Foxp3+ regulatory T cells.

    Directory of Open Access Journals (Sweden)

    Franco Carranza

    Full Text Available Dendritic cells (DC have the potential to control the outcome of autoimmunity by modulating the immune response. In this study, we tested the ability of Fasciola hepatica total extract (TE to induce tolerogenic properties in CpG-ODN (CpG maturated DC, to then evaluate the therapeutic potential of these cells to diminish the inflammatory response in collagen induced arthritis (CIA. DBA/1J mice were injected with TE plus CpG treated DC (T/C-DC pulsed with bovine collagen II (CII between two immunizations with CII and clinical scores CIA were determined. The levels of CII-specific IgG2 and IgG1 in sera, the histological analyses in the joints, the cytokine profile in the draining lymph node (DLN cells and in the joints, and the number, and functionality of CD4+CD25+Foxp3+ T cells (Treg were evaluated. Vaccination of mice with CII pulsed T/C-DC diminished the severity and incidence of CIA symptoms and the production of the inflammatory cytokine, while induced the production of anti-inflammatory cytokines. The therapeutic effect was mediated by Treg cells, since the adoptive transfer of CD4+CD25+ T cells, inhibited the inflammatory symptoms in CIA. The in vitro blockage of TGF-β in cultures of DLN cells plus CII pulsed T/C-DC inhibited the expansion of Treg cells. Vaccination with CII pulsed T/C-DC seems to be a very efficient approach to diminish exacerbated immune response in CIA, by inducing the development of Treg cells, and it is therefore an interesting candidate for a cell-based therapy for rheumatoid arthritis (RA.

  10. Helminth antigens enable CpG-activated dendritic cells to inhibit the symptoms of collagen-induced arthritis through Foxp3+ regulatory T cells.

    Science.gov (United States)

    Carranza, Franco; Falcón, Cristian Roberto; Nuñez, Nicolás; Knubel, Carolina; Correa, Silvia Graciela; Bianco, Ismael; Maccioni, Mariana; Fretes, Ricardo; Triquell, María Fernanda; Motrán, Claudia Cristina; Cervi, Laura

    2012-01-01

    Dendritic cells (DC) have the potential to control the outcome of autoimmunity by modulating the immune response. In this study, we tested the ability of Fasciola hepatica total extract (TE) to induce tolerogenic properties in CpG-ODN (CpG) maturated DC, to then evaluate the therapeutic potential of these cells to diminish the inflammatory response in collagen induced arthritis (CIA). DBA/1J mice were injected with TE plus CpG treated DC (T/C-DC) pulsed with bovine collagen II (CII) between two immunizations with CII and clinical scores CIA were determined. The levels of CII-specific IgG2 and IgG1 in sera, the histological analyses in the joints, the cytokine profile in the draining lymph node (DLN) cells and in the joints, and the number, and functionality of CD4+CD25+Foxp3+ T cells (Treg) were evaluated. Vaccination of mice with CII pulsed T/C-DC diminished the severity and incidence of CIA symptoms and the production of the inflammatory cytokine, while induced the production of anti-inflammatory cytokines. The therapeutic effect was mediated by Treg cells, since the adoptive transfer of CD4+CD25+ T cells, inhibited the inflammatory symptoms in CIA. The in vitro blockage of TGF-β in cultures of DLN cells plus CII pulsed T/C-DC inhibited the expansion of Treg cells. Vaccination with CII pulsed T/C-DC seems to be a very efficient approach to diminish exacerbated immune response in CIA, by inducing the development of Treg cells, and it is therefore an interesting candidate for a cell-based therapy for rheumatoid arthritis (RA).

  11. A Case of Plasmacytoid Dendritic Cell Leukemia

    Directory of Open Access Journals (Sweden)

    Köpeczi Judit Beáta

    2013-04-01

    Full Text Available Introduction: Plasmacytoid dendritic cell leukemia is a rare subtype of acute leukemia, which has recently been established as a distinct pathologic entity that typically follows a highly aggressive clinical course in adults. The aim of this report is to present a case of plasmacytoid dendritic cell leukemia due to its rarity and difficulty to recognize and diagnose it.

  12. Interaction of Mycoplasma hominis PG21 with Human Dendritic Cells: Interleukin-23-Inducing Mycoplasmal Lipoproteins and Inflammasome Activation of the Cell.

    Science.gov (United States)

    Goret, J; Béven, L; Faustin, B; Contin-Bordes, C; Le Roy, C; Claverol, S; Renaudin, H; Bébéar, C; Pereyre, S

    2017-08-01

    Mycoplasma hominis lacks a cell wall, and lipoproteins anchored to the extracellular side of the plasma membrane are in direct contact with the host components. A Triton X-114 extract of M. hominis enriched with lipoproteins was shown to stimulate the production of interleukin-23 (IL-23) by human dendritic cells (hDCs). The inflammasome activation of the host cell has never been reported upon M. hominis infection. We studied here the interaction between M. hominis PG21 and hDCs by analyzing both the inflammation-inducing mycoplasmal lipoproteins and the inflammasome activation of the host cell. IL-23-inducing lipoproteins were determined using a sequential extraction strategy with two nondenaturing detergents, Sarkosyl and Triton X-114, followed by SDS-PAGE separation and mass spectrometry identification. The activation of the hDC inflammasome was assessed using PCR array and enzyme-linked immunosorbent assay (ELISA). We defined a list of 24 lipoproteins that could induce the secretion of IL-23 by hDCs, 5 with a molecular mass between 20 and 35 kDa and 19 with a molecular mass between 40 and 100 kDa. Among them, lipoprotein MHO_4720 was identified as potentially bioactive, and a synthetic lipopeptide corresponding to the N-terminal part of the lipoprotein was subsequently shown to induce IL-23 release by hDCs. Regarding the hDC innate immune response, inflammasome activation with caspase-dependent production of IL-1β was observed. After 24 h of coincubation of hDCs with M. hominis, downregulation of the NLRP3-encoding gene and of the adaptor PYCARD-encoding gene was noticed. Overall, this study provides insight into both protagonists of the interaction of M. hominis and hDCs.IMPORTANCEMycoplasma hominis is a human urogenital pathogen involved in gynecologic and opportunistic infections. M. hominis lacks a cell wall, and its membrane contains many lipoproteins that are anchored to the extracellular side of the plasma membrane. In the present study, we focused on

  13. Dendritic web silicon for solar cell application

    Science.gov (United States)

    Seidensticker, R. G.

    1977-01-01

    The dendritic web process for growing long thin ribbon crystals of silicon and other semiconductors is described. Growth is initiated from a thin wirelike dendrite seed which is brought into contact with the melt surface. Initially, the seed grows laterally to form a button at the melt surface; when the seed is withdrawn, needlelike dendrites propagate from each end of the button into the melt, and the web portion of the crystal is formed by the solidification of the liquid film supported by the button and the bounding dendrites. Apparatus used for dendritic web growth, material characteristics, and the two distinctly different mechanisms involved in the growth of a single crystal are examined. The performance of solar cells fabricated from dendritic web material is indistinguishable from the performance of cells fabricated from Czochralski grown material.

  14. Dendritic cells and their role in periodontal disease.

    Science.gov (United States)

    Wilensky, A; Segev, H; Mizraji, G; Shaul, Y; Capucha, T; Shacham, M; Hovav, A-H

    2014-03-01

    T cells, particularly CD4+ T cells, play a central role in both progression and control of periodontal disease, whereas the contribution of the various CD4+ T helper subsets to periodontal destruction remains controversial, the activation, and regulation of these cells is orchestrated by dendritic cells. As sentinels of the oral mucosa, dendritic cells encounter and capture oral microbes, then migrate to the lymph node where they regulate the differentiation of CD4+ T cells. It is thus clear that dendritic cells are of major importance in the course of periodontitis, as they hold the immunological cues delivered by the pathogen and the surrounding environment, allowing them to induce destructive immunity. In recent years, advanced immunological techniques and new mouse models have facilitated in vivo studies that have provided new insights into the developmental and functional aspects of dendritic cells. This progress has also benefited the characterization of oral dendritic cells, as well as to their function in periodontitis. Here, we provide an overview of the various gingival dendritic cell subsets and their distribution, while focusing on their role in periodontal bone loss.

  15. Stimulation by means of dendritic cells followed by Epstein-Barr virus-transformed B cells as antigen-presenting cells is more efficient than dendritic cells alone in inducing Aspergillus f16-specific cytotoxic T cell responses.

    Science.gov (United States)

    Zhu, F; Ramadan, G; Davies, B; Margolis, D A; Keever-Taylor, C A

    2008-02-01

    Adoptive immunotherapy with in vitro expanded antigen-specific cytotoxic T lymphocytes (CTLs) may be an effective approach to prevent, or even treat, Aspergillus (Asp) infections. Such lines can be generated using monocyte-derived dendritic cells (DC) as antigen-presenting cells (APC) but requires a relatively high volume of starting blood. Here we describe a method that generates Asp-specific CTL responses more efficiently using a protocol of antigen presented on DC followed by Epstein-Barr virus (EBV)-transformed B lymphoblastoid cell lines (BLCL) as APC. Peripheral blood mononuclear cells were stimulated weekly (2-5x) with a complete pool of pentadecapeptides (PPC) spanning the coding region of Asp f16 pulsed onto autologous mature DC. Cultures were split and stimulated subsequently with either PPC-DC or autologous PPC-pulsed BLCL (PPC-BLCL). Lines from the DC/BLCL arm demonstrated Asp f16-specific cytotoxicity earlier and to a higher degree than lines generated with PPC-DC alone. The DC/BLCL-primed lines showed a higher frequency of Asp f16-specific interferon (IFN)-gamma producing cells but an identical effector cell phenotype and peptide specificity compared to PPC-DC-only-primed lines. Tumour necrosis factor (TNF)-alpha, but not IL-10, appeared to play a role in the effectiveness of BLCL as APC. These results demonstrate that BLCL serve as highly effective APC for the stimulation of Asp f16-specific T cell responses and that a culture approach using initial priming with PPC-DC followed by PPC-BLCL may be a more effective method to generate Asp f16-specific T cell lines and requires less starting blood than priming with PPC-DC alone.

  16. Dendritic Cells for Anomaly Detection

    CERN Document Server

    Greensmith, Julie; Aickelin, Uwe

    2010-01-01

    Artificial immune systems, more specifically the negative selection algorithm, have previously been applied to intrusion detection. The aim of this research is to develop an intrusion detection system based on a novel concept in immunology, the Danger Theory. Dendritic Cells (DCs) are antigen presenting cells and key to the activation of the human signals from the host tissue and correlate these signals with proteins know as antigens. In algorithmic terms, individual DCs perform multi-sensor data fusion based on time-windows. The whole population of DCs asynchronously correlates the fused signals with a secondary data stream. The behaviour of human DCs is abstracted to form the DC Algorithm (DCA), which is implemented using an immune inspired framework, libtissue. This system is used to detect context switching for a basic machine learning dataset and to detect outgoing portscans in real-time. Experimental results show a significant difference between an outgoing portscan and normal traffic.

  17. Characterization of T-regulatory cells, induced by immature dendritic cells, which inhibit enteroantigen-reactive colitis-inducing T-cell responses in vitro and in vivo

    DEFF Research Database (Denmark)

    Gad, Monika; Kristensen, Nanna N; Kury, Evelyn

    2004-01-01

    -injected into severe combined immunodeficiency (SCID) mice with colitis-inducing CD4(+) CD25(-) T cells. Both unfractionated CD4(+) and purified CD25(+) Treg cells fully protected the recipients against the development of colitis. In contrast, co-transfer of fractionated CD25(-) T cells offered no protection against...

  18. Combined role of seizure-induced dendritic morphology alterations and spine loss in newborn granule cells with mossy fiber sprouting on the hyperexcitability of a computer model of the dentate gyrus.

    Science.gov (United States)

    Tejada, Julian; Garcia-Cairasco, Norberto; Roque, Antonio C

    2014-05-01

    Temporal lobe epilepsy strongly affects hippocampal dentate gyrus granule cells morphology. These cells exhibit seizure-induced anatomical alterations including mossy fiber sprouting, changes in the apical and basal dendritic tree and suffer substantial dendritic spine loss. The effect of some of these changes on the hyperexcitability of the dentate gyrus has been widely studied. For example, mossy fiber sprouting increases the excitability of the circuit while dendritic spine loss may have the opposite effect. However, the effect of the interplay of these different morphological alterations on the hyperexcitability of the dentate gyrus is still unknown. Here we adapted an existing computational model of the dentate gyrus by replacing the reduced granule cell models with morphologically detailed models coming from three-dimensional reconstructions of mature cells. The model simulates a network with 10% of the mossy fiber sprouting observed in the pilocarpine (PILO) model of epilepsy. Different fractions of the mature granule cell models were replaced by morphologically reconstructed models of newborn dentate granule cells from animals with PILO-induced Status Epilepticus, which have apical dendritic alterations and spine loss, and control animals, which do not have these alterations. This complex arrangement of cells and processes allowed us to study the combined effect of mossy fiber sprouting, altered apical dendritic tree and dendritic spine loss in newborn granule cells on the excitability of the dentate gyrus model. Our simulations suggest that alterations in the apical dendritic tree and dendritic spine loss in newborn granule cells have opposing effects on the excitability of the dentate gyrus after Status Epilepticus. Apical dendritic alterations potentiate the increase of excitability provoked by mossy fiber sprouting while spine loss curtails this increase.

  19. Combined role of seizure-induced dendritic morphology alterations and spine loss in newborn granule cells with mossy fiber sprouting on the hyperexcitability of a computer model of the dentate gyrus.

    Directory of Open Access Journals (Sweden)

    Julian Tejada

    2014-05-01

    Full Text Available Temporal lobe epilepsy strongly affects hippocampal dentate gyrus granule cells morphology. These cells exhibit seizure-induced anatomical alterations including mossy fiber sprouting, changes in the apical and basal dendritic tree and suffer substantial dendritic spine loss. The effect of some of these changes on the hyperexcitability of the dentate gyrus has been widely studied. For example, mossy fiber sprouting increases the excitability of the circuit while dendritic spine loss may have the opposite effect. However, the effect of the interplay of these different morphological alterations on the hyperexcitability of the dentate gyrus is still unknown. Here we adapted an existing computational model of the dentate gyrus by replacing the reduced granule cell models with morphologically detailed models coming from three-dimensional reconstructions of mature cells. The model simulates a network with 10% of the mossy fiber sprouting observed in the pilocarpine (PILO model of epilepsy. Different fractions of the mature granule cell models were replaced by morphologically reconstructed models of newborn dentate granule cells from animals with PILO-induced Status Epilepticus, which have apical dendritic alterations and spine loss, and control animals, which do not have these alterations. This complex arrangement of cells and processes allowed us to study the combined effect of mossy fiber sprouting, altered apical dendritic tree and dendritic spine loss in newborn granule cells on the excitability of the dentate gyrus model. Our simulations suggest that alterations in the apical dendritic tree and dendritic spine loss in newborn granule cells have opposing effects on the excitability of the dentate gyrus after Status Epilepticus. Apical dendritic alterations potentiate the increase of excitability provoked by mossy fiber sprouting while spine loss curtails this increase.

  20. Ceramide formation is involved in Lactobacillus acidophilus-induced IFN-beta response in dendritic cells

    DEFF Research Database (Denmark)

    Fuglsang, Eva; Henningsen, Louise; Frøkiær, Hanne

    of sphingomyelin to ceramide by acid sphingomyelinase (ASMase) at the outer leaflet of the PM is a key event in endocytosis of gram-positive Lactobacillus acidophilus (L. acidophilus) and the subsequent induction of IFN-beta in DCs and, as the gram-negative Escherichia coli (E. coli) does not induce appreciable...... amounts of IFN-beta, the ASMase activity would affect endocytosis and the ensuing cytokine response of L. acidophilus and E. coli differently. SMase or an inhibitor of ASMase and acid ceramidase, chlorpromazine (CPZ), was added to DCs prior to stimulation with either of the bacteria. Endocytosis...... of fluorescent bacteria +/- FITC-dextran was measured by flow cytometry and gene expression and cytokine response of IFN-beta and IL-12 was measured by qPCR and ELISA, respectively. Addition of SMase increased the uptake of L. acidophilus and L. acidophilus-induced IL-12/IFN-beta but showed no effect...

  1. Dexamethasone prevents granulocyte-macrophage colony-stimulating factor-induced nuclear factor-κB activation, inducible nitric oxide synthase expression and nitric oxide production in a skin dendritic cell line

    Directory of Open Access Journals (Sweden)

    Ana Luísa Vital

    2003-01-01

    Full Text Available Aims: Nitric oxide (NO has been increasingly implicated in inflammatory skin diseases, namely in allergic contact dermatitis. In this work, we investigated the effect of dexamethasone on NO production induced by the epidermal cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF in a mouse fetal skin dendritic cell line.

  2. CD40 engagement on dendritic cells induces cyclooxygenase-2 and EP2 receptor via p38 and ERK MAPKs.

    Science.gov (United States)

    Harizi, Hedi; Limem, Ilef; Gualde, Norbert

    2011-02-01

    We have previously reported that cyclooxygenase (COX)-2-derived prostaglandin (PG)E2 critically regulates dendritic cell (DC) inflammatory phenotype and function through EP2/EP4 receptor subtypes. As genes activated by CD40 engagement are directly relevant to inflammation, we examined the effects of CD40 activation on inflammatory PGs in murine bone marrow-derived DC (mBM-DC). We showed for the first time that activation of mBM-DC with agonist anti-CD40 monoclonal antibody (anti-CD40 mAb) dose dependently induces the synthesis of significant amounts of PGE2 via inducible expression of COX-2 enzyme, as NS-398, a COX-2-selective inhibitor reduces this upregulation. In contrast to lipopolysaccharide, which upregulates mBM-DC surface levels of EP2 and EP4 receptors, CD40 crosslinking on mBM-DC increases EP2, but not EP4, receptor expression. Flow cytometry analysis and radioligand-binding assay showed that EP2 was the major EP receptor subtype, which binds to PGE2 at the surface of anti-CD40-activated mBM-DC. Upregulation of COX-2 and EP2 levels by CD40 engagement was accompanied by dose-dependent phosphorylation of p38 and ERK1/2 mitogen-activated protein kinase (MAPK) and was abrogated by inhibitors of both pathways. Collectively, we demonstrated that CD40 engagement on mBM-DC upregulates COX-2 and EP2 receptor expression through activation of p38 and ERK1/2 MAPK signaling. Triggering the PGE2/EP2 pathway by anti-CD40 mAb resulted on the induction of Th2 immune response. Thus, CD40-induced production of PGE2 by mBM-DC could represent a negative feedback mechanism involving EP2 receptor and limiting the propagation of Th1 responses. Blocking CD40 pathway may represent a novel therapeutic pathway of inhibiting COX-2-derived prostanoids in chronically inflamed tissues (that is, arthritis).

  3. A Fusion Protein between Streptavidin and the Endogenous TLR4 Ligand EDA Targets Biotinylated Antigens to Dendritic Cells and Induces T Cell Responses In Vivo

    Directory of Open Access Journals (Sweden)

    Laura Arribillaga

    2013-01-01

    Full Text Available The development of tools for efficient targeting of antigens to antigen presenting cells is of great importance for vaccine development. We have previously shown that fusion proteins containing antigens fused to the extra domain A from fibronectin (EDA, an endogenous TLR4 ligand, which targets antigens to TLR4-expressing dendritic cells (DC, are highly immunogenic. To facilitate the procedure of joining EDA to any antigen of choice, we have prepared the fusion protein EDAvidin by linking EDA to the N terminus of streptavidin, allowing its conjugation with biotinylated antigens. We found that EDAvidin, as streptavidin, forms tetramers and binds biotin or biotinylated proteins with a Kd ~ 2.6 × 10−14 mol/L. EDAvidin favours the uptake of biotinylated green fluorescent protein by DC. Moreover, EDAvidin retains the proinflammatory properties of EDA, inducing NF-κβ by TLR4-expressing cells, as well as the production of TNF-α by the human monocyte cell line THP1 and IL-12 by DC. More importantly, immunization of mice with EDAvidin conjugated with the biotinylated nonstructural NS3 protein from hepatitis C virus induces a strong anti-NS3 T cell immune response. These results open a new way to use the EDA-based delivery tool to target any antigen of choice to DC for vaccination against infectious diseases and cancer.

  4. Pseudomonas aeruginosa quorum-sensing signal molecules interfere with dendritic cell-induced T-cell proliferation

    DEFF Research Database (Denmark)

    Skindersø, Mette Elena; Zeuthen, Louise; Pedersen, Susanne Brix

    2009-01-01

    a decreased ability to induce T-cell proliferation in vitro. Collectively, this suggests that OdDHL and PQS change the maturation pattern of stimulated DCs away from a proinflammatory T-helper type I directing response, thereby decreasing the antibacterial activity of the adaptive immune defence. Od...

  5. Flt3/Flt3L Participates in the Process of Regulating Dendritic Cells and Regulatory T Cells in DSS-Induced Colitis

    Directory of Open Access Journals (Sweden)

    Jing-Wei Mao

    2014-01-01

    Full Text Available The immunoregulation between dendritic cells (DCs and regulatory T cells (T-regs plays an important role in the pathogenesis of ulcerative colitis (UC. Recent research showed that Fms-like tyrosine kinase 3 (Flt3 and Flt3 ligand (Flt3L were involved in the process of DCs regulating T-regs. The DSS-induced colitis model is widely used because of its simplicity and many similarities with human UC. In this study, we observe the disease activity index (DAI and histological scoring, detect the amounts of DCs and T-regs and expression of Flt3/Flt3L, and investigate Flt3/Flt3L participating in the process of DCs regulating T-regs in DSS-induced colitis. Our findings suggest that the reduction of Flt3 and Flt3L expression may possibly induce colonic immunoregulatory imbalance between CD103+MHCII+DCs and CD4+CD25+FoxP3+T-regs in DSS-induced colitis. Flt3/Flt3L participates in the process of regulating DCS and T-regs in the pathogenesis of UC, at least, in the acute stage of this disease.

  6. Dendritic cells are stressed out in tumor.

    Science.gov (United States)

    Maj, Tomasz; Zou, Weiping

    2015-09-01

    A recently paper published in Cell reports that dendritic cells (DCs) are dysfunctional in the tumor environment. Tumor impairs DC function through induction of endoplasmic reticulum stress response and subsequent disruption of lipid metabolic homeostasis.

  7. IL-10 and IL-27 producing dendritic cells capable of enhancing IL-10 production of T cells are induced in oral tolerance.

    Science.gov (United States)

    Shiokawa, Aya; Tanabe, Kosuke; Tsuji, Noriko M; Sato, Ryuichiro; Hachimura, Satoshi

    2009-06-30

    Oral tolerance is a key feature of intestinal immunity, generating systemic tolerance to ingested antigens (Ag). Dendritic cells (DC) have been revealed as important immune regulators, however, the precise role of DC in oral tolerance induction remains unclear. We investigated the characteristics of DC in spleen, mesenteric lymph node (MLN), and Peyer's patch (PP) after oral Ag administration in a TCR-transgenic mouse model. DC from PP and MLN of tolerized mice induced IL-10 production but not Foxp3 expression in cocultured T cells. IL-10 production was markedly increased after 5-7-day Ag administration especially in PP DC. On the other hand, IL-27 production was increased after 2-5-day Ag administration. CD11b(+) DC, which increased after ingestion of Ag, prominently expressed IL-10 and IL-27 compared with CD11b(-) DC. These results suggest that IL-10 and IL-27 producing DC are increased by interaction with antigen specific T cells in PP, and these DC act as an inducer of IL-10 producing T cells in oral tolerance.

  8. Lactic Acid Bacteria Strains Exert Immunostimulatory Effect on H. pylori-Induced Dendritic Cells

    Directory of Open Access Journals (Sweden)

    Małgorzata Wiese

    2015-01-01

    Full Text Available The aim of this study was to find out if selected lactic acid bacteria (LAB strains (antagonistic or nonantagonistic against H. pylori in vitro would differ in their abilities to modulate the DCs maturation profiles reflected by their phenotype and cytokine expression patterns. Methods. Monocyte-derived DCs maturation was elicited by their direct exposure to the LAB strains of L. rhamnosus 900 or L. paracasei 915 (antagonistic and nonantagonistic to H. pylori, resp., in the presence or absence of H. pylori strain cagA+. The DCs maturation profile was assessed on the basis of surface markers expression and cytokines production. Results. We observed that the LAB strains and the mixtures of LAB with H. pylori are able to induce mature DCs. At the same time, the L. paracasei 915 leads to high IL-10/IL-12p70 cytokine ratio, in contrast to L. rhamnosus 900. Conclusions. This study showed that the analyzed lactobacilli strains are more potent stimulators of DC maturation than H. pylori. Interestingly from the two chosen LAB strains the antagonistic to H. pylori-L. rhamnosus strain 900 has more proinflammatory and probably antibactericidal properties.

  9. H2-M3-restricted CD8+ T cells induced by peptide-pulsed dendritic cells confer protection against Mycobacterium tuberculosis.

    Science.gov (United States)

    Doi, Takehiko; Yamada, Hisakata; Yajima, Toshiki; Wajjwalku, Worawidh; Hara, Toshiro; Yoshikai, Yasunobu

    2007-03-15

    One of the oligopolymorphic MHC class Ib molecules, H2-M3, presents N-formylated peptides derived from bacteria. In this study, we tested the ability of an H2-M3-binding peptide, TB2, to induce protection in C57BL/6 mice against Mycobacterium tuberculosis. Immunization with bone marrow-derived dendritic cell (BMDC) pulsed with TB2 or a MHC class Ia-binding peptide, MPT64(190-198) elicited an expansion of Ag-specific CD8+ T cells in the spleen and the lung. The number of TB2-specific CD8+ T cells reached a peak on day 6, contracted with kinetics similar to MPT64(190-198)-specific CD8+ T cells and was maintained at an appreciable level for at least 60 days. The TB2-specific CD8+ T cells produced less effector cytokines but have stronger cytotoxic activity than MPT64(190-198)-specific CD8+ T cells. Mice immunized with TB2-pulsed BMDC as well as those with MPT64(190-198)-pulsed BMDC showed significant protection against an intratracheal challenge with M. tuberculosis H37Rv. However, histopathology of the lung in mice immunized with TB2-pulsed BMDC was different from mice immunized with MPT64(190-198)-pulsed BMDC. Our results suggest that immunization with BMDC pulsed with MHC class Ib-restricted peptides would be a useful vaccination strategy against M. tuberculosis.

  10. Immune tolerance induced by intravenous transfer of immature dendritic cells via up-regulating numbers of suppressive IL-10(+) IFN-γ(+)-producing CD4(+) T cells.

    Science.gov (United States)

    Zhou, Fang; Ciric, Bogoljub; Zhang, Guang-Xian; Rostami, Abdolmohamad

    2013-05-01

    Dendritic cells (DCs) regulate immunity and immune tolerance in vivo. However, the mechanisms of DC-mediated tolerance have not been fully elucidated. Here, we demonstrate that intravenous (i.v.) transfer of bone marrow-derived DCs pulsed with myelin oligodendrocyte glycoprotein (MOG) peptide blocks the development of experimental autoimmune encephalomyelitis in C57BL/6J mice. i.v. transfer of MOG-pulsed DCs leads to the down-regulation of the production of IL-17A and IFN-γ and up-regulation of IL-10 secretion. The development of regulatory T cells (Tregs) is facilitated via up-regulation of FoxP3 expression and production of IL-10. The number of suppressive CD4(+)IL-10(+)IFN-γ(+) T cells is also improved. The expression of OX40, CD154, and CD28 is down-regulated, but the expression of CD152, CD80, PD-1, ICOS, and BTLA is up-regulated on CD4(+) T cells after i.v. transfer of immature DCs. The expression of CCR4, CCR5, and CCR7 on CD4(+) T cells is also improved. Our results suggest that immature DCs may induce tolerance via facilitating the development of CD4(+)FoxP3(+) Tregs and suppressive CD4(+)IL-10(+)IFN-γ(+) T cells in vivo.

  11. Vitamin C Attenuates Hemorrhagic Shock-induced Dendritic Cell-specific Intercellular Adhesion Molecule 3-grabbing Nonintegrin Expression in Tubular Epithelial Cells and Renal Injury in Rats

    Institute of Scientific and Technical Information of China (English)

    Li Ma; Jian Fei; Ying Chen; Bing Zhao; Zhi-Tao Yang; Lu Wang; Hui-Qiu Sheng

    2016-01-01

    Background:The expression of dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN) in renal tubular epithelial cells has been thought to be highly correlated with the occurrence of several kidney diseases,but whether it takes place in renal tissues during hemorrhagic shock (HS) is unknown.The present study aimed to investigate this phenomenon and the inhibitory effect of Vitamin C (VitC).Methods:A Sprague-Dawley rat HS model was established in vivo in this study.The expression level and location of DC-SIGN were observed in kidneys.Also,the degree of histological damage,the concentrations of tumor necrosis factor-α and interleukin-6 in the renal tissues,and the serum concentration of blood urea nitrogen and creatinine at different times (2-24 h) after HS (six rats in each group),with or without VitC treatment before resuscitation,were evaluated.Results:HS induced DC-SIGN expression in rat tubular epithelial cells.The proinflammatory cytokine concentration,histological damage scores,and functional injury of kidneys had increased.All these phenomena induced by HS were relieved when the rats were treated with VitC before resuscitation.Conclusions:The results of the present study illustrated that HS could induce tubular epithelial cells expressing DC-SIGN,and the levels of proinflammatory cytokines in the kidney tissues improved correspondingly.The results also indicated that VitC could suppress the DC-SIGN expression in the tubular epithelial cells induced by HS and alleviate the inflammation and functional injury in the kidney.

  12. Chlamydia pneumoniae infection induced allergic airway sensitization is controlled by regulatory T-cells and plasmacytoid dendritic cells.

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    Timothy R Crother

    Full Text Available Chlamydia pneumoniae (CP is associated with induction and exacerbation of asthma. CP infection can induce allergic airway sensitization in mice in a dose- and time-dependent manner. Allergen exposure 5 days after a low dose (mild-moderate, but not a high dose (severe CP infection induces antigen sensitization in mice. Innate immune signals play a critical role in controlling CP infection induced allergic airway sensitization, however these mechanisms have not been fully elucidated. Wild-type, TLR2-/-, and TLR4-/- mice were infected intranasally (i.n. with a low dose of CP, followed by i.n. exposure to human serum albumin (HSA and challenged with HSA 2 weeks later. Airway inflammation, immunoglobulins, eosinophils, and goblet cells were measured. Low dose CP infection induced allergic sensitization in TLR2-/- mice, but not in TLR4-/- mice, due to differential Treg responses in these genotypes. TLR2-/- mice had reduced numbers of Tregs in the lung during CP infection while TLR4-/- mice had increased numbers. High dose CP infection resulted in an increase in Tregs and pDCs in lungs, which prevented antigen sensitization in WT mice. Depletion of Tregs or pDCs resulted in allergic airway sensitization. We conclude that Tregs and pDCs are critical determinants regulating CP infection-induced allergic sensitization. Furthermore, TLR2 and TLR4 signaling during CP infection may play a regulatory role through the modulation of Tregs.

  13. Chlamydia pneumoniae infection induced allergic airway sensitization is controlled by regulatory T-cells and plasmacytoid dendritic cells.

    Science.gov (United States)

    Crother, Timothy R; Schröder, Nicolas W J; Karlin, Justin; Chen, Shuang; Shimada, Kenichi; Slepenkin, Anatoly; Alsabeh, Randa; Peterson, Ellena; Arditi, Moshe

    2011-01-01

    Chlamydia pneumoniae (CP) is associated with induction and exacerbation of asthma. CP infection can induce allergic airway sensitization in mice in a dose- and time-dependent manner. Allergen exposure 5 days after a low dose (mild-moderate), but not a high dose (severe) CP infection induces antigen sensitization in mice. Innate immune signals play a critical role in controlling CP infection induced allergic airway sensitization, however these mechanisms have not been fully elucidated. Wild-type, TLR2-/-, and TLR4-/- mice were infected intranasally (i.n.) with a low dose of CP, followed by i.n. exposure to human serum albumin (HSA) and challenged with HSA 2 weeks later. Airway inflammation, immunoglobulins, eosinophils, and goblet cells were measured. Low dose CP infection induced allergic sensitization in TLR2-/- mice, but not in TLR4-/- mice, due to differential Treg responses in these genotypes. TLR2-/- mice had reduced numbers of Tregs in the lung during CP infection while TLR4-/- mice had increased numbers. High dose CP infection resulted in an increase in Tregs and pDCs in lungs, which prevented antigen sensitization in WT mice. Depletion of Tregs or pDCs resulted in allergic airway sensitization. We conclude that Tregs and pDCs are critical determinants regulating CP infection-induced allergic sensitization. Furthermore, TLR2 and TLR4 signaling during CP infection may play a regulatory role through the modulation of Tregs.

  14. Mesenchymal stem cells derived from human exfoliated deciduous teeth (SHEDs induce immune modulatory profile in monocyte-derived dendritic cells.

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    Fernando de Sá Silva

    Full Text Available BACKGROUND: Mesenchymal stem cells have prominent immune modulatory properties, which may have clinical applications; however their major source, bone marrow, is of limited availability. On the other hand, mesenchymal stem cells derived from human exfoliated deciduous teeth (SHEDs are readily accessible, but their immune regulatory properties have not been completely investigated. This study was designed, therefore, to evaluate the SHEDs influence on DCs differentiation, maturation, ability to activate T cells and to expand CD4(+Foxp3(+ T cells. METHODOLOGY/PRINCIPAL FINDINGS: The experiments were based in cellular co-culture during differentiation and maturation of monocyte derived-DCs (moDCs, with, or not, presence of SHEDs. After co-culture with SHEDs, (moDCs presented lower expression of BDCA-1 and CD11c, in comparison to DC cultivated without SHEDs. CD40, CD80, CD83 and CD86 levels were also decreased in mature DCs (mDCs after co-cultivation with SHEDs. To assess the ability of SHEDs-exposed moDCs to modulate T cell responses, the former were separated from SHEDs, and co-cultured with peripheral blood lymphocytes. After 5 days, the proliferation of CD4(+ and CD8(+ T cells was evaluated and found to be lower than that induced by moDCs cultivated without SHEDs. In addition, an increase in the proportion of CD4(+Foxp3(+IL-10(+ T cells was observed among cells stimulated by mature moDCs that were previously cultivated with SHEDs. Soluble factors released during co-cultures also showed a reduction in the pro-inflammatory cytokines (IL-2, TNF-α and IFN-γ, and an increase in the anti-inflammatory molecule IL-10. CONCLUSION/SIGNIFICANCE: This study shows that SHEDs induce an immune regulatory phenotype in moDCs cells, evidenced by changes in maturation and differentiation rates, inhibition of lymphocyte stimulation and ability to expand CD4(+Foxp3(+ T cells. Further characterization and validation of this phenomenon could support the use of SHEDs

  15. The hookworm tissue inhibitor of metalloproteases (Ac-TMP-1 modifies dendritic cell function and induces generation of CD4 and CD8 suppressor T cells.

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    Carmen Cuéllar

    Full Text Available Hookworm infection is a major cause of disease burden for humans. Recent studies have described hookworm-related immunosuppression in endemic populations and animal models. A Tissue Inhibitor of Metalloproteases (Ac-TMP-1 has been identified as one of the most abundant proteins released by the adult parasite. We investigated the effect of recombinant Ac-TMP-1 on dendritic cell (DC and T cell function. Splenic T cells from C57BL/6 mice injected with Ac-TMP-1 showed reduced proliferation to restimulation with anti CD3 or bystander antigens such as OVA. Incubation of bone marrow-derived DCs with Ac-TMP-1 decreased MHC Class I and, especially, Class II expression but increased CD86 and IL-10 expression. Co-incubation of splenic T cells with DCs pulsed with Ac-TMP-1 induced their differentiation into CD4+ and, particularly, CD8+ CD25+Foxp3+ T cells that expressed IL-10. These cells were able to suppress proliferation of naïve and activated CD4+ T cells by TGF-Beta-dependent (CD4+ suppressors or independent (CD8+ suppressors mechanisms. Priming of DCs with non-hookworm antigens, such as OVA, did not result in the generation of suppressor T cells. These data indicate that Ac-TMP-1 initiates the development of a regulatory response through modifications in DC function and generation of suppressor T cells. This is the first report to propose a role of suppressor CD8+ T cells in gastrointestinal helminthic infections.

  16. Dendritic Cells Induce a Subpopulation of IL-12Rβ2-Expressing Treg that Specifically Consumes IL-12 to Control Th1 Responses.

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    Sela, Uri; Park, Chae Gyu; Park, Andrew; Olds, Peter; Wang, Shu; Steinman, Ralph M; Fischetti, Vincent A

    2016-01-01

    Cytokines secreted from dendritic cells (DCs) play an important role in the regulation of T helper (Th) cell differentiation and activation into effector cells. Therefore, controlling cytokine secretion from DCs may potentially regulate Th differentiation/activation. DCs also induce de-novo generation of regulatory T cells (Treg) that modulate the immune response. In the current study we used the mixed leukocyte reaction (MLR) to investigate the effect of allospecific Treg on IL-12, TNFα and IL-6 secretion by DCs. Treg cells were found to markedly down-regulate IL-12 secretion from DCs following stimulation with TLR7/8 agonist. This down-regulation of IL-12 was neither due to a direct suppression of its production by the DCs nor a result of marked DC death. We found that IL-12 was rather actively consumed by Treg cells. IL-12 consumption was mediated by a subpopulation of IL-12Rβ2-expressing Treg cells and was dependent on MHC class-II expressed on dendritic cells. Furthermore, IL-12 consumption by Tregs increased their suppressive effect on T cell proliferation and Th1 activation. These results provide a new pathway of Th1 response regulation where IL-12 secreted by DCs is consumed by a sub-population of IL-12Rβ2-expressing Treg cells. Consumption of IL-12 by Tregs not only reduces the availability of IL-12 to Th effector cells but also enhances the Treg immunosuppressive effect. This DC-induced IL-12Rβ2-expressing Treg subpopulation may have a therapeutic advantage in suppressing Th1 mediated autoimmunity.

  17. Phenotypical and functional characterization of clinical-grade dendritic cells.

    NARCIS (Netherlands)

    Vries, I.J.M. de; Adema, G.J.; Punt, C.J.A.; Figdor, C.G.

    2005-01-01

    Dendritic cells (DC) are the most potent antigen-presenting cells and form a promising new treatment modality. Fully activated DC loaded with antigen are very useful in stimulating immune responses, in particular those to combat cancer. Immature DC can either cause immunological tolerance or induce

  18. Immature and maturation-resistant human dendritic cells generated from bone marrow require two stimulations to induce T cell anergy in vitro.

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    Thomas G Berger

    Full Text Available Immature dendritic cells (DC represent potential clinical tools for tolerogenic cellular immunotherapy in both transplantation and autoimmunity. A major drawback in vivo is their potential to mature during infections or inflammation, which would convert their tolerogenicity into immunogenicity. The generation of immature DC from human bone marrow (BM by low doses of GM-CSF (lowGM in the absence of IL-4 under GMP conditions create DC resistant to maturation, detected by surface marker expression and primary stimulation by allogeneic T cells. This resistence could not be observed for BM-derived DC generated with high doses of GM-CSF plus IL-4 (highGM/4, although both DC types induced primary allogeneic T cell anergy in vitro. The estabishment of the anergic state requires two subsequent stimulations by immature DC. Anergy induction was more profound with lowGM-DC due to their maturation resistance. Together, we show the generation of immature, maturation-resistant lowGM-DC for potential clinical use in transplant rejection and propose a two-step-model of T cell anergy induction by immature DC.

  19. Artificial Dendritic Cells: Multi-faceted Perspectives

    CERN Document Server

    Greensmith, Julie

    2009-01-01

    Dendritic cells are the crime scene investigators of the human immune system. Their function is to correlate potentially anomalous invading entities with observed damage to the body. The detection of such invaders by dendritic cells results in the activation of the adaptive immune system, eventually leading to the removal of the invader from the host body. This mechanism has provided inspiration for the development of a novel bio-inspired algorithm, the Dendritic Cell Algorithm. This algorithm processes information at multiple levels of resolution, resulting in the creation of information granules of variable structure. In this chapter we examine the multi-faceted nature of immunology and how research in this field has shaped the function of the resulting Dendritic Cell Algorithm. A brief overview of the algorithm is given in combination with the details of the processes used for its development. The chapter is concluded with a discussion of the parallels between our understanding of the human immune system a...

  20. HIV-1 Reservoir Dynamics after Vaccination and Antiretroviral Therapy Interruption Are Associated with Dendritic Cell Vaccine-Induced T Cell Responses.

    Science.gov (United States)

    Andrés, Cristina; Plana, Montserrat; Guardo, Alberto C; Alvarez-Fernández, Carmen; Climent, Nuria; Gallart, Teresa; León, Agathe; Clotet, Bonaventura; Autran, Brigitte; Chomont, Nicolas; Gatell, Josep M; Sánchez-Palomino, Sonsoles; García, Felipe

    2015-09-01

    HIV-1-specific immune responses induced by a dendritic cell (DC)-based therapeutic vaccine might have some effect on the viral reservoir. Patients on combination antiretroviral therapy (cART) were randomized to receive DCs pulsed with autologous HIV-1 (n = 24) (DC-HIV-1) or nonpulsed DCs (n = 12) (DC-control). We measured the levels of total and integrated HIV-1 DNA in CD4 T cells isolated from these patients at 6 time points: before any cART; before the first cART interruption, which was at 56 weeks before the first immunization to isolate virus for pulsing DCs; before and after vaccinations (VAC1 and VAC2); and at weeks 12 and 48 after the second cART interruption. The vaccinations did not influence HIV-1 DNA levels in vaccinated subjects. After the cART interruption at week 12 postvaccination, while total HIV-1 DNA increased significantly in both arms, integrated HIV-1 DNA did not change in vaccinees (mean of 1.8 log10 to 1.9 copies/10(6) CD4 T cells, P = 0.22) and did increase in controls (mean of 1.8 log10 to 2.1 copies/10(6) CD4 T cells, P = 0.02) (P = 0.03 for the difference between groups). However, this lack of increase of integrated HIV-1 DNA observed in the DC-HIV-1 group was transient, and at week 48 after cART interruption, no differences were observed between the groups. The HIV-1-specific T cell responses at the VAC2 time point were inversely correlated with the total and integrated HIV-1 DNA levels after cART interruption in vaccinees (r [Pearson's correlation coefficient] = -0.69, P = 0.002, and r = -0.82, P HIV-1-specific T cell immune responses elicited by DC therapeutic vaccines drive changes in HIV-1 DNA after vaccination and cART interruption. (This study has been registered at ClinicalTrials.gov under registration no. NCT00402142.) There is an intense interest in developing strategies to target HIV-1 reservoirs as they create barriers to curing the disease. The development of therapeutic vaccines aimed at enhancing immune-mediated clearance

  1. Retrospective Comparative Study of the Effects of Dendritic Cell Vaccine and Cytokine-Induced Killer Cell Immunotherapy with that of Chemotherapy Alone and in Combination for Colorectal Cancer

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    Jingxiu Niu

    2014-01-01

    Full Text Available Purpose. This retrospective study determined the delayed-type hypersensitivity (DTH skin test and safety of dendritic cell (DC vaccine and cytokine-induced killer (CIK cell immunotherapy and the survival compared to chemotherapy in 239 colorectal cancer (CRC patients. Methods. DTH and safety of the immunotherapy were recorded. The overall survival (OS and disease free survival curves were compared according to the immunotherapy and/or chemotherapy received with Kaplan-Meier estimates. Results. Of the 70 patients who received immunotherapy, 62.86% had a positive DTH skin test, 38.57% developed fever, 47.14% developed insomnia, 38.57% developed anorexia, 4.29% developed joint soreness, and 11.43% developed skin rash. For 204 resectable CRC patients, median survival time (MST (198.00 days was significantly longer in patients with immunotherapy plus chemotherapy than with chemotherapy alone (106.00 days (P=0.02. For 35 patients with unresectable or postsurgery relapsed CRC and who were confirmed to be dead, no statistical difference was observed in the MST between the patients treated with immunotherapy and with chemotherapy (P=0.41. MST in the patients treated with chemotherapy plus immunotherapy was 154 days longer than that of patients treated with chemotherapy alone (P=0.41. Conclusions. DC vaccination and CIK immunotherapy did not cause severe adverse effects, induce immune response against CRC, and prolong OS.

  2. Activated protein C modulates the proinflammatory activity of dendritic cells

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    Matsumoto T

    2015-05-01

    Full Text Available Takahiro Matsumoto,1,2* Yuki Matsushima,1* Masaaki Toda,1 Ziaurahman Roeen,1 Corina N D'Alessandro-Gabazza,1,5 Josephine A Hinneh,1 Etsuko Harada,1,3 Taro Yasuma,4 Yutaka Yano,4 Masahito Urawa,1,5 Tetsu Kobayashi,5 Osamu Taguchi,5 Esteban C Gabazza1 1Department of Immunology, Mie University Graduate School of Medicine, Tsu, Mie Prefecture, 2BONAC Corporation, BIO Factory 4F, Fukuoka, 3Iwade Research Institute of Mycology, 4Department of Endocrinology, Diabetes and Metabolism, 5Department of Pulmonary and Critical Care Medicine, Mie University Graduate School of Medicine, Tsu, Mie Prefecture, Japan *These authors contributed equally to this work Background: Previous studies have demonstrated the beneficial activity of activated protein C in allergic diseases including bronchial asthma and rhinitis. However, the exact mechanism of action of activated protein C in allergies is unclear. In this study, we hypothesized that pharmacological doses of activated protein C can modulate allergic inflammation by inhibiting dendritic cells. Materials and methods: Dendritic cells were prepared using murine bone marrow progenitor cells and human peripheral monocytes. Bronchial asthma was induced in mice that received intratracheal instillation of ovalbumin-pulsed dendritic cells. Results: Activated protein C significantly increased the differentiation of tolerogenic plasmacytoid dendritic cells and the secretion of type I interferons, but it significantly reduced lipopolysaccharide-mediated maturation and the secretion of inflammatory cytokines in myeloid dendritic cells. Activated protein C also inhibited maturation and the secretion of inflammatory cytokines in monocyte-derived dendritic cells. Activated protein C-treated dendritic cells were less effective when differentiating naïve CD4 T-cells from Th1 or Th2 cells, and the cellular effect of activated protein C was mediated by its receptors. Mice that received adoptive transfer of activated protein C

  3. PD-L1 blockade improves immune dysfunction of spleen dendritic cells and T-cells in zymosan-induced multiple organs dysfunction syndromes.

    Science.gov (United States)

    Liu, Qian; Lv, Yi; Zhao, Min; Jin, Yiduo; Lu, Jiangyang

    2015-01-01

    This research is to investigate the role of tolerant spleen dendritic cells (DC) in multiple organs dysfunction syndromes (MODS) at late stage. Tolerant DC and MODS were induced by intraperotineal injection of zymosan. The immunity of DC was determined by examining interleukin (IL)-10, IL-12, IL-2, major histocompatibility complex (MHC), CD86, programmed death (PD-1), programmed death ligand 1 (PD-L1), paired immunoglobulin-like receptor B (PIR-B) or T-cell proliferation in serum, spleen homogenate, DC culture or DC/T-cell co-culture. The PD-L1/PD-1 pathway was blocked using PD-L1 antibody. The IL-12p70 in serum, spleen homogenate and DC culture supernatant were decreased at 5 d and 12 d after zymosan injection while the IL-12p40 and IL-10 were increased. The expression of MHC, cluster of differentiation 86 (CD86), PD-1 and PD-L1 in spleen DCs were increased at early stage after zymosan injection. At 5 d and 12 d, the expression of MHC and CD86 was reduced while the expression of PD-1, PD-L1 and PIR-B was increased, accompanied with decreased proliferation of T-cell and decrease of IL-2 in spleen and serum. Application of PD-L1 antibody improved the above changes. At late stage of MODS mice induced by zymosan, the expression of co-stimulators and inhibitors in spleen DCs was imbalanced to form tolerant DCs which reduced the activation of T-cells. PD-L1 antibody improved the immune tolerance of DCs through intervening PD-1/PD-L1 pathway, and attenuated the inhibition of T-cell activities by tolerant DCs and the immune inhibition.

  4. Exposure to ionizing radiation induces the migration of cutaneous dendritic cells by a CCR7-dependent mechanism.

    Science.gov (United States)

    Cummings, Ryan J; Gerber, Scott A; Judge, Jennifer L; Ryan, Julie L; Pentland, Alice P; Lord, Edith M

    2012-11-01

    In the event of a deliberate or accidental radiological emergency, the skin would likely receive substantial ionizing radiation (IR) poisoning, which could negatively impact cellular proliferation, communication, and immune regulation within the cutaneous microenvironment. Indeed, as we have previously shown, local IR exposure to the murine ear causes a reduction of two types of cutaneous dendritic cells (cDC), including interstitial dendritic cells of the dermis and Langerhans cells of the epidermis, in a dose- and time-dependent manner. These APCs are critical regulators of skin homeostasis, immunosurveillance, and the induction of T and B cell-mediated immunity, as previously demonstrated using conditional cDC knockout mice. To mimic a radiological emergency, we developed a murine model of sublethal total body irradiation (TBI). Our data would suggest that TBI results in the reduction of cDC from the murine ear that was not due to a systemic response to IR, as a loss was not observed in shielded ears. We further determined that this reduction was due, in part, to the upregulation of the chemoattractant CCL21 on lymphatic vessels as well as CCR7 expressed on cDC. Migration as a potential mechanism was confirmed using CCR7(-/-) mice in which cDC were not depleted following TBI. Finally, we demonstrated that the loss of cDC following TBI results in an impaired contact hypersensitivity response to hapten by using a modified contact hypersensitivity protocol. Taken together, these data suggest that IR exposure may result in diminished immunosurveillance in the skin, which could render the host more susceptible to pathogens.

  5. Cigarette smoke promotes dendritic cell accumulation in COPD; a Lung Tissue Research Consortium study

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    Yi Eunhee S

    2010-04-01

    Full Text Available Abstract Background Abnormal immune responses are believed to be highly relevant in the pathogenesis of chronic obstructive pulmonary disease (COPD. Dendritic cells provide a critical checkpoint for immunity by their capacity to both induce and suppress immunity. Although evident that cigarette smoke, the primary cause of COPD, significantly influences dendritic cell functions, little is known about the roles of dendritic cells in the pathogenesis of COPD. Methods The extent of dendritic cell infiltration in COPD tissue specimens was determined using immunohistochemical localization of CD83+ cells (marker of matured myeloid dendritic cells, and CD1a+ cells (Langerhans cells. The extent of tissue infiltration with Langerhans cells was also determined by the relative expression of the CD207 gene in COPD versus control tissues. To determine mechanisms by which dendritic cells accumulate in COPD, complimentary studies were conducted using monocyte-derived human dendritic cells exposed to cigarette smoke extract (CSE, and dendritic cells extracted from mice chronically exposed to cigarette smoke. Results In human COPD lung tissue, we detected a significant increase in the total number of CD83+ cells, and significantly higher amounts of CD207 mRNA when compared with control tissue. Human monocyte-derived dendritic cells exposed to CSE (0.1-2% exhibited enhanced survival in vitro when compared with control dendritic cells. Murine dendritic cells extracted from mice exposed to cigarette smoke for 4 weeks, also demonstrated enhanced survival compared to dendritic cells extracted from control mice. Acute exposure of human dendritic cells to CSE induced the cellular pro-survival proteins heme-oxygenase-1 (HO-1, and B cell lymphoma leukemia-x(L (Bcl-xL, predominantly through oxidative stress. Although activated human dendritic cells conditioned with CSE expressed diminished migratory CCR7 expression, their migration towards the CCR7 ligand CCL21 was not

  6. Modulation of tolerogenic dendritic cells and autoimmunity.

    Science.gov (United States)

    Kim, Sun Jung; Diamond, Betty

    2015-05-01

    A key function of dendritic cells (DCs) is to induce either immune tolerance or immune activation. Many new DC subsets are being recognized, and it is now clear that each DC subset has a specialized function. For example, different DC subsets may express different cell surface molecules and respond differently to activation by secretion of a unique cytokine profile. Apart from intrinsic differences among DC subsets, various immune modulators in the microenvironment may influence DC function; inappropriate DC function is closely related to the development of immune disorders. The most exciting recent advance in DC biology is appreciation of human DC subsets. In this review, we discuss functionally different mouse and human DC subsets both in lymphoid organs and non-lymphoid organs, the molecules that regulate DC function, and the emerging understanding of the contribution of DCs to autoimmune diseases.

  7. Helicobacter pylori induces in-vivo expansion of human regulatory T cells through stimulating interleukin-1β production by dendritic cells.

    Science.gov (United States)

    Mitchell, P J; Afzali, B; Fazekasova, H; Chen, D; Ali, N; Powell, N; Lord, G M; Lechler, R I; Lombardi, G

    2012-12-01

    Helicobacter pylori is one of the most common infections in the world. Despite inciting inflammation, immunological clearance of the pathogen is often incomplete. CD4(+) CD25(hi) forkhead box protein 3 (FoxP3(+)) regulatory T cells (T(regs)) are potent suppressors of different types of immune responses and have been implicated in limiting inflammatory responses to H. pylori. Investigating the influence of H. pylori on T(reg) function and proliferation, we found that H. pylori-stimulated dendritic cells (DCs) induced proliferation in T(regs) and impaired their suppressive capability. This effect was mediated by interleukin (IL)-1β produced by H. pylori-stimulated DCs. These data correlated with in-vivo observations in which H. pylori(+) gastric mucosa contained more T(regs) in active cell division than uninfected stomachs. Inciting local proliferation of T(regs) and inhibiting their suppressive function may represent a mechanism for the chronic gastritis and carcinogenesis attributable to H. pylori.

  8. Monocyte-derived dendritic cells induce a house dust mite-specific Th2 allergic inflammation in the lung of humanized SCID mice: involvement of CCR7.

    Science.gov (United States)

    Hammad, Hamida; Lambrecht, Bart N; Pochard, Pierre; Gosset, Philippe; Marquillies, Philippe; Tonnel, André-Bernard; Pestel, Joël

    2002-08-01

    In rodents, airway dendritic cells (DCs) capture inhaled Ag, undergo maturation, and migrate to the draining mediastinal lymph nodes (MLN) to initiate the Ag-specific T cell response. However, the role of human DCs in the pathogenesis of the Th2 cell-mediated disease asthma remains to be clarified. Here, by using SCID mice engrafted with T cells from either house dust mite (HDM)-allergic patients or healthy donors, we show that DCs pulsed with Der p 1, one of the major allergens of HDM, and injected intratracheally into naive animals migrated into the MLN. In the MLN, Der p 1-pulsed DCs from allergic patients induced the proliferation of IL-4-producing CD4(+) T cells, whereas those from healthy donors induced IFN-gamma-secreting cells. In reconstituted human PBMC-reconstituted SCID mice primed with pulsed DCs from allergic patients, repeated exposure to aerosols of HDM induced 1) a strong pulmonary inflammatory reaction rich in T cells and eosinophils, 2) an increase in IL-4 and IL-5 production in the lung lavage fluid, and 3) increased IgE production compared with that in mice primed with unpulsed DCs. All these effects were reduced following in vivo neutralization of the CCR7 ligand secondary lymphoid tissue chemokine. These data in human PBMC-reconstituted SCID mice show that monocyte-derived DCs might play a key role in the pathogenesis of the pulmonary allergic response by inducing Th2 effector function following migration to the MLN.

  9. Peroxisome proliferator-activated receptor α agonist attenuates oxidized-low density lipoprotein induced immune maturation of human monocyte-derived dendritic cells

    Institute of Scientific and Technical Information of China (English)

    SHI Hong-yu; CAO Xue-tao; GE Jun-bo; FANG Wei-yi; YAO Kang; SUN Ai-jun; HUANG Rong-chong; JIA Qing-zhe; WANG Ke-qiang; ZOU Yun-zeng

    2008-01-01

    @@ Accumulating evidence suggests that the Th1 immune response induced by various antigens such as oxidized low density lipoprotein (ox-LDL) and heat shock proteins (HSPs) play a key role in the process of atherosclerosis.1 Dendritic cells (DCs) are the most potent antigen-presenting cells (APCs) in the body with the unique ability to initiate a primary immune response to certain antigens by the activation of "naive" T cells.2 The maturation of DC with the upregulation of costimulatory molecules such as CD83,CD40,CD86,and major histocompatibility complex (MHC) class molecules such as human leukocyte antigen (HLA)-DR,is required for DC to activate T cells.

  10. Epidermal cells are the primary phagocytes in the fragmentation and clearance of degenerating dendrites in Drosophila.

    Science.gov (United States)

    Han, Chun; Song, Yuanquan; Xiao, Hui; Wang, Denan; Franc, Nathalie C; Jan, Lily Yeh; Jan, Yuh-Nung

    2014-02-05

    During developmental remodeling, neurites destined for pruning often degenerate on-site. Physical injury also induces degeneration of neurites distal to the injury site. Prompt clearance of degenerating neurites is important for maintaining tissue homeostasis and preventing inflammatory responses. Here we show that in both dendrite pruning and dendrite injury of Drosophila sensory neurons, epidermal cells rather than hemocytes are the primary phagocytes in clearing degenerating dendrites. Epidermal cells act via Draper-mediated recognition to facilitate dendrite degeneration and to engulf and degrade degenerating dendrites. Using multiple dendritic membrane markers to trace phagocytosis, we show that two members of the CD36 family, croquemort (crq) and debris buster (dsb), act at distinct stages of phagosome maturation for dendrite clearance. Our finding reveals the physiological importance of coordination between neurons and their surrounding epidermis, for both dendrite fragmentation and clearance.

  11. Lactobacillus crispatus strain SJ-3C-US induces human dendritic cells (DCs) maturation and confers an anti-inflammatory phenotype to DCs.

    Science.gov (United States)

    Eslami, Solat; Hadjati, Jamshid; Motevaseli, Elahe; Mirzaei, Reza; Farashi Bonab, Samad; Ansaripour, Bita; Khoramizadeh, Mohammad Reza

    2016-08-01

    Lactobacillus crispatus is one of the most predominant species in the healthy vagina microbiota. Nevertheless, the interactions between this commensal bacterium and the immune system are largely unknown. Given the importance of the dendritic cells (DCs) in the regulation of the immunity, this study was performed to elucidate the influence of vaginal isolated L. crispatus SJ-3C-US from healthy Iranian women on DCs, either directly by exposure of DCs to ultraviolet-inactivated (UVI) and heat-killed (HK) L. crispatus SJ-3C-US or indirectly to its cell-free supernatant (CFS), and the outcomes of immune response. In this work we showed that L. crispatus SJ-3C-US induced strong dose-dependent activation of dendritic cells and production of high levels of IL-10, whereas IL-12p70 production was induced at low level in an inverse dose-dependent manner. This stimulation skewed T cells polarization toward CD4(+) CD25(+) FOXP3(+) Treg cells and production of IL-10 in a dose-dependent manner in mixed leukocyte reaction (MLR) test. The mode of bacterial inactivation did not affect the DCs activation pattern, upon encounter with L. crispatus SJ-3C-US. Moreover, while DCs stimulated with CFS showed moderate phenotypic maturation and IL-10 production, it failed to skew T cells polarization toward CD4(+) CD25(+) FOXP3(+) regulatory T cells (Treg) and production of IL-10. This study showed that L. crispatus SJ-3C-US confers an anti-inflammatory phenotype to DCs through up-regulation of anti-inflammatory/regulatory IL-10 cytokine production and induction of CD4(+) CD25(+) FOXP3(+) T cells at optimal dosage. Our findings suggest that L. crispatus SJ-3C-US could be a potent candidate as protective probiotic against human immune-mediated pathologies, such as chronic inflammation, vaginitis or pelvic inflammatory disease (PID).

  12. Human intestinal dendritic cells as controllers of mucosal immunity

    Directory of Open Access Journals (Sweden)

    David Bernardo

    2013-06-01

    Full Text Available Dendritic cells are the most potent, professional antigen-presenting cells in the body; following antigen presentation they control the type (proinflammatory/regulatory of immune response that will take place, as well as its location. Given their high plasticity and maturation ability in response to local danger signals derived from innate immunity, dendritic cells are key actors in the connection between innate immunity and adaptive immunity responses. In the gut dendritic cells control immune tolerance mechanisms against food and/or commensal flora antigens, and are also capable of initiating an active immune response in the presence of invading pathogens. Dendritic cells are thus highly efficient in controlling the delicate balance between tolerance and immunity in an environment so rich in antigens as the gut, and any factor involving these cells may impact their function, ultimately leading to the development of bowel conditions such as celiac disease or inflammatory bowel disease. In this review we shall summarize our understanding of human intestinal dendritic cells, their ability to express and induce migration markers, the various environmental factors modulating their properties, their subsets in the gut, and the problems entailed by their study, including identification strategies, differences between humans and murine models, and phenotypical variations along the gastrointestinal tract.

  13. Molecular programming of steady-state dendritic cells: impact on autoimmunity and tumor immune surveillance.

    Science.gov (United States)

    Johnson, Dylan J; Ohashi, Pamela S

    2013-05-01

    Dendritic cells are master regulators of immunity. Immature dendritic cells are essential for maintaining self-tolerance, while mature dendritic cells initiate a variety of specialized immune responses. Dendritic cell quiescence is often viewed as a default state that requires exogenous stimuli to induce maturation. However, recent studies have identified dendritic cell quiescence factors that actively program dendritic cells to an immature state. In the absence of these factors, dendritic cells spontaneously become immunogenic and can induce autoimmune responses. Herein we discuss two such factors, NF-κB1 and A20, that preserve dendritic cell immaturity through their regulation of NF-κB signaling. Loss of either of these factors increases dendritic cell immunogenicity, suggesting that they may be important targets for enhancing dendritic cell-based cancer immunotherapies. Alternatively, defects in molecules critical for maintaining steady-state DCs may provide novel biomarkers that identify patients who have enhanced natural antitumor immunity or that correlate with better responses to various immunotherapies.

  14. Gene-inducing program of human dendritic cells in response to BCG cell-wall skeleton (CWS), which reflects adjuvancy required for tumor immunotherapy.

    Science.gov (United States)

    Ishii, Kazuo; Kurita-Taniguchi, Mitsue; Aoki, Mikio; Kimura, Toru; Kashiwazaki, Yasuo; Matsumoto, Misako; Seya, Tsukasa

    2005-05-15

    Adjuvants induce the expression of a number of genes in dendritic cells (DCs), which facilitate effective antigen-presentation and cytokine/chemokine liberation. It has been accepted that the toll-like receptor (TLR) family governs the adjuvant activity in DCs. An adjuvant with a long history is mycobacteria in an oil-in-water emulsion, namely Freund's complete adjuvant. Since the active center for the adjuvancy in mycobacteria is the cell-wall skeleton (CWS), we used the bacillus Calmette-Guerin cell-wall skeleton (BCG-CWS) to test DC maturation by GeneChip analysis. We identified the genes supporting an efficient DC response and output. Approximately 2000 genes were up-regulated by BCG-CWS stimulation. BCG-CWS-, peptidoglycan (PGN)- and lipopolysaccharide (LPS)-stimulation generally up-regulated some gene clusters including genes for inflammatory cytokines (TNF, IL1alpha, IL1beta, IL6, IL12 p40, IL23 p19, etc.), chemokines (CCL20, IL8, etc.), cell adhesion molecules (ICAM-1, etc.), apoptosis-related proteins (GADD45B, BCL2A1, etc.), metabolic enzymes (PTGS2, SOD2, etc.) and miscellaneous proteins (EHD1, TNFAIP6, etc.). LPS-stimulation, but not BCG-CWS- or PGN-stimulation, up-regulated the interferon-inducible antiviral proteins, including IFIT1, IFIT2, IFIT4, CXCL10, ISG15, OASL, IFITM1 and MX1. We also found that the BCG-CWS- or PGN-stimulation up-regulated CXCL5, MMP1, etc. We discussed their properties in association with TLRs and recently discovered TLR adapters.

  15. Dendritic Cells in the Cancer Microenvironment

    Directory of Open Access Journals (Sweden)

    Yang Ma, Galina V. Shurin, Zhu Peiyuan, Michael R. Shurin

    2013-01-01

    Full Text Available The complexity of the tumor immunoenvironment is underscored by the emergence and discovery of different subsets of immune effectors and regulatory cells. Tumor-induced polarization of immune cell differentiation and function makes this unique environment even more intricate and variable. Dendritic cells (DCs represent a special group of cells that display different phenotype and activity at the tumor site and exhibit differential pro-tumorigenic and anti-tumorigenic functions. DCs play a key role in inducing and maintaining the antitumor immunity, but in the tumor environment their antigen-presenting function may be lost or inefficient. DCs might be also polarized into immunosuppressive/tolerogenic regulatory DCs, which limit activity of effector T cells and support tumor growth and progression. Although various factors and signaling pathways have been described to be responsible for abnormal functioning of DCs in cancer, there are still no feasible therapeutic modalities available for preventing or reversing DC malfunction in tumor-bearing hosts. Thus, better understanding of DC immunobiology in cancer is pivotal for designing novel or improved therapeutic approaches that will allow proper functioning of DCs in patients with cancer.

  16. Evaluation on the Clinical Efifcacy of Dendritic Cell-Activated Cytokine-Induced Killer Cells Combined with Conventional Therapy in the Treatment of Malignant Tumors

    Institute of Scientific and Technical Information of China (English)

    WEI Hong; HAN Na-na; CAI Xin-hua

    2016-01-01

    Objective: To evaluate the clinical efficacy of dendritic cell-activated cytokine-induced killer (DC-CIK) cells combined with conventional therapy in the treatment of malignant tumors. Methods: A total of 100 patients with malignant tumors were randomly divided into two groups. Treatment group received conventional therapy combined with DC-CIK while control group received conventional therapy alone. The short-term efficacy, adverse reactions and changes of lymphocyte subpopulation were all compared between two groups after treatment. Results: The overall response rate (ORR) was higher in treatment group (86.00%) than in control group (54.00%), the difference was statistically significant (P0.05). WBC reduced markedly, but the level of alanine aminotransferase (ALT) increased obviously after treatment in control group (P0.05). In treatment group, the levels of CD3+, CD3+CD4+, CD3+CD8+, and CD3+CD56+ increased (P0.05). In control group, the levels of CD3+ and CD3+CD4+ reduced (P0.05). The levels of CD3+, CD3+CD4+, CD3+CD8+and CD3+CD56+ in treatment group were higher than those in control group (P Conclusion:DC-CIK combined with conventional therapy, safe and effective, is capable of promoting the recovery of leukocytes and liver and kidney function, and improving the cellular immune function, which may provide a new therapeutic regimen for patients with malignant tumors.

  17. The role of dendritic cells in the generation of CD4(+) CD25(HI) Foxp3(+) T cells induced by amino acid copolymers.

    Science.gov (United States)

    Kawamoto, Norio; Ohnishi, Hidenori; Kondo, Naomi; Strominger, Jack L

    2013-01-01

    The effects of the amino acid copolymers used in the therapy of experimental autoimmune encephalomyelitis, poly(Y,E,A,K)(n) (Copaxone(®)) and poly(Y,F,A,K)(n), on murine myeloid cells have been investigated. After administration of these copolymers to mice, increases in several splenic myeloid cell populations were observed, including CD11b(+) CD11c(+) dendritic cells. The latter were the major splenic cell type that secreted CCL22 (macrophage-derived chemokine) on stimulation with amino acid copolymers. CCL22 secretion was also stimulated from bone marrow-derived dendritic cells (BMDC) generated with GM-CSF in much larger amounts than from bone marrow-derived macrophages generated with M-CSF. Moreover, CCL22 secretion could also be obtained using BMDC generated from two different types of MHC II(-/-) mice, indicating that an innate immune receptor is involved. Finally, incubation of these BMDC or splenic dendritic cells with naive CD4(+) CD25(-) T cells resulted in formation of CD4(+) CD25(HI) Foxp3 T cells (~25% of which were Foxp3(+)). The number of these regulatory cells was doubled by pretreatment of BMDC with amino acid copolymers.

  18. The Polyunsaturated Fatty Acids Arachidonic Acid and Docosahexaenoic Acid Induce Mouse Dendritic Cells Maturation but Reduce T-Cell Responses In Vitro.

    Science.gov (United States)

    Carlsson, Johan A; Wold, Agnes E; Sandberg, Ann-Sofie; Östman, Sofia M

    2015-01-01

    Long-chain polyunsaturated fatty acids (PUFAs) might regulate T-cell activation and lineage commitment. Here, we measured the effects of omega-3 (n-3), n-6 and n-9 fatty acids on the interaction between dendritic cells (DCs) and naïve T cells. Spleen DCs from BALB/c mice were cultured in vitro with ovalbumin (OVA) with 50 μM fatty acids; α-linolenic acid, arachidonic acid (AA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), linoleic acid or oleic acid and thereafter OVA-specific DO11.10 T cells were added to the cultures. Fatty acids were taken up by the DCs, as shown by gas chromatography analysis. After culture with arachidonic acid or DHA CD11c+ CD11b+ and CD11c+ CD11bneg DCs expressed more CD40, CD80, CD83, CD86 and PDL-1, while IAd remained unchanged. However, fewer T cells co-cultured with these DCs proliferated (CellTrace Violet low) and expressed CD69 or CD25, while more were necrotic (7AAD+). We noted an increased proportion of T cells with a regulatory T cell (Treg) phenotype, i.e., when gating on CD4+ FoxP3+ CTLA-4+, CD4+ FoxP3+ Helios+ or CD4+ FoxP3+ PD-1+, in co-cultures with arachidonic acid- or DHA-primed DCs relative to control cultures. The proportion of putative Tregs was inversely correlated to T-cell proliferation, indicating a suppressive function of these cells. With arachidonic acid DCs produced higher levels of prostaglandin E2 while T cells produced lower amounts of IL-10 and IFNγ. In conclusion arachidonic acid and DHA induced up-regulation of activation markers on DCs. However arachidonic acid- and DHA-primed DCs reduced T-cell proliferation and increased the proportion of T cells expressing FoxP3, indicating that these fatty acids can promote induction of regulatory T cells.

  19. The Polyunsaturated Fatty Acids Arachidonic Acid and Docosahexaenoic Acid Induce Mouse Dendritic Cells Maturation but Reduce T-Cell Responses In Vitro

    Science.gov (United States)

    Carlsson, Johan A.; Wold, Agnes E.; Sandberg, Ann-Sofie; Östman, Sofia M.

    2015-01-01

    Long-chain polyunsaturated fatty acids (PUFAs) might regulate T-cell activation and lineage commitment. Here, we measured the effects of omega-3 (n-3), n-6 and n-9 fatty acids on the interaction between dendritic cells (DCs) and naïve T cells. Spleen DCs from BALB/c mice were cultured in vitro with ovalbumin (OVA) with 50 μM fatty acids; α-linolenic acid, arachidonic acid (AA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), linoleic acid or oleic acid and thereafter OVA-specific DO11.10 T cells were added to the cultures. Fatty acids were taken up by the DCs, as shown by gas chromatography analysis. After culture with arachidonic acid or DHA CD11c+ CD11b+ and CD11c+ CD11bneg DCs expressed more CD40, CD80, CD83, CD86 and PDL-1, while IAd remained unchanged. However, fewer T cells co-cultured with these DCs proliferated (CellTrace Violetlow) and expressed CD69 or CD25, while more were necrotic (7AAD+). We noted an increased proportion of T cells with a regulatory T cell (Treg) phenotype, i.e., when gating on CD4+ FoxP3+ CTLA-4+, CD4+ FoxP3+ Helios+ or CD4+ FoxP3+ PD-1+, in co-cultures with arachidonic acid- or DHA-primed DCs relative to control cultures. The proportion of putative Tregs was inversely correlated to T-cell proliferation, indicating a suppressive function of these cells. With arachidonic acid DCs produced higher levels of prostaglandin E2 while T cells produced lower amounts of IL-10 and IFNγ. In conclusion arachidonic acid and DHA induced up-regulation of activation markers on DCs. However arachidonic acid- and DHA-primed DCs reduced T-cell proliferation and increased the proportion of T cells expressing FoxP3, indicating that these fatty acids can promote induction of regulatory T cells. PMID:26619195

  20. Immature dendritic cells generated from cryopreserved human monocytes show impaired ability to respond to LPS and to induce allogeneic lymphocyte proliferation.

    Directory of Open Access Journals (Sweden)

    Guilherme Ferreira Silveira

    Full Text Available Dendritic cells play a key role in the immune system, in the sensing of foreign antigens and triggering of an adaptive immune response. Cryopreservation of human monocytes was investigated to understand its effect on differentiation into immature monocyte-derived dendritic cells (imdDCs, the response to inflammatory stimuli and the ability to induce allogeneic lymphocyte proliferation. Cryopreserved (crp-monocytes were able to differentiate into imdDCs, albeit to a lesser extent than freshly (frh-obtained monocytes. Furthermore, crp-imdDCs had lower rates of maturation and cytokine/chemokine secretion in response to LPS than frh-imdDCs. Lower expression of Toll-like receptor 4 (at 24 and 48 h and higher susceptibility to apoptosis in crp-imdDCs than in fresh cells would account for the impaired maturation and cytokine/chemokine secretion observed. A mixed leukocyte reaction showed that lymphocyte proliferation was lower with crp-imdDCs than with frh-imdDCs. These findings suggested that the source of monocytes used to generate human imdDCs could influence the accuracy of results observed in studies of the immune response to pathogens, lymphocyte activation, vaccination and antigen sensing. It is not always possible to work with freshly isolated monocytes but the possible effects of freezing/thawing on the biology and responsiveness of imdDCs should be taken into account.

  1. Targeting antigens to Dec-205 on dendritic cells induces a higher immune response in chickens: Hemagglutinin of avian influenza virus example.

    Science.gov (United States)

    Jáuregui-Zúñiga, David; Pedraza-Escalona, Martha; Espino-Solís, Gerardo Pavel; Quintero-Hernández, Verónica; Olvera-Rodríguez, Alejandro; Díaz-Salinas, Marco Aurelio; López, Susana; Possani, Lourival Domingos

    2016-12-09

    It is widely known that targeting a variety of antigens to the DEC-205 receptor on dendritic cells (DCs) significantly potentiate immunity. This communication reports the development of a new murine monoclonal antibody (mAb) against the chicken DEC-205, using as immunogen the carbohydrate recognition domain-2 (CRD-2) heterologously expressed. This mAb recognizes a protein band of 250kDa by immunoprecipitation analysis and shows strong cross-reactivity with human and pig DEC-205. Furthermore, the hemagglutinin (HA) of avian influenza H5N2 virus was cloned and expressed using insect cell-baculovirus expression system. We chemically conjugated the anti-chicken DEC-205 antibody with the highly purified HA to direct the antigen to the dendritic cells and evaluate the immune response elicited in vivo by this conjugate. A single dose of chemical conjugate was sufficient to elicit a strong immune response in chickens as early as fourteen days after priming. In addition, the conjugate induced an earlier and higher response compared to unconjugated HA. These results suggest that the strategy described here has potential to be used in the future design and development of successful vaccines against different chicken infectious diseases with direct impact in biotechnology and veterinary fields.

  2. Tumor's other immune targets: dendritic cells.

    Science.gov (United States)

    Esche, C; Lokshin, A; Shurin, G V; Gastman, B R; Rabinowich, H; Watkins, S C; Lotze, M T; Shurin, M R

    1999-08-01

    The induction of apoptosis in T cells is one of several mechanisms by which tumors escape immune recognition. We have investigated whether tumors induce apoptosis in dendritic cells (DC) by co-culture of murine or human DC with different tumor cell lines for 4-48 h. Analysis of DC morphological features, JAM assay, TUNEL, caspase-3-like and transglutaminase activity, Annexin V binding, and DNA fragmentation assays revealed a time- and dose-dependent induction of apoptosis in DC by tumor-derived factors. This finding is both effector and target specific. The mechanism of tumor-induced DC apoptosis involved regulation of Bcl-2 and Bax expression. Double staining of both murine and human tumor tissues confirmed that tumor-associated DC undergo apoptotic death in vivo. DC isolated from tumor tissue showed significantly higher levels of apoptosis as determined by TUNEL assay when compared with DC isolated from spleen. These findings demonstrate that tumors induce apoptosis in DC and suggest a new mechanism of tumor escape from immune recognition. DC protection from apoptosis will lead to improvement of DC-based immunotherapies for cancer and other immune diseases.

  3. Dendritic cells in melanoma - immunohistochemical study and research trends.

    Science.gov (United States)

    Nedelcu, Roxana Ioana; Ion, Daniela Adriana; Holeab, Cosmin Adrian; Cioplea, Mirela Daniela; Brînzea, Alice; Zurac, Sabina Andrada

    2015-01-01

    Cutaneous dendritic cells play multiple physiological roles and are involved in various pathophysiological processes. Research studies of dendritic cells abound in the medical literature. Nevertheless, the role of dendritic cells in melanoma regression phenomenon is not completely understood. We conducted a scientometric analysis in order to highlight the current state on research regarding dendritic cells and melanoma. We also performed an immunohistochemical study, using specific markers for dendritic cells (CD1a, langerin). We evaluated the frequency and distribution of dendritic cells in areas of tumor regression compared to the areas of inflammatory infiltrate of melanoma without regression. The immunohistochemical study we performed revealed that dendritic cells are more frequent in the regressed areas, comparing with non-regressed ones. In regressed areas, dendritic cells have a predominant nodular pattern (19 cases), followed by diffuse isolate pattern (eight cases) and mixed pattern (diffuse and nodular) (three cases). In melanoma without regression, most cases presented a diffuse pattern (27 cases) of dendritic cells distribution. In conclusion, our immunohistochemical study stressed differences between frequency and distribution of dendritic cells located in the melanoma with regression and melanoma without regression. These data suggest that dendritic cells are involved in the regression phenomenon. Following the literature analysis we obtained, we observed that dendritic cells profile in melanoma with regression was poorly studied. Insights into antitumor immune response and dendritic cells may be essential for the understanding of the potential prognostic role of dendritic cells in melanoma and for the development of new promising therapeutic strategies for melanoma.

  4. Recombinant mammaglobin A adenovirus-infected dendritic cells induce mammaglobin A-specific CD8+ cytotoxic T lymphocytes against breast cancer cells in vitro.

    Directory of Open Access Journals (Sweden)

    Huixia Cui

    Full Text Available Mammaglobin A (MGBA is a novel breast cancer-associated antigen almost exclusively over-expressed in primary and metastatic human breast cancers, making it a potential therapeutic target for breast cancer. The development of dendritic cell (DC-induced tumor antigen specific CD8(+ cytotoxic T lymphocytes (CTLs may hold promise in cancer immunotherapy. In this study we constructed recombinant replication-defective adenoviral (Ad vectors encoding MGBA and evaluated their ability to trigger anti-tumor immunity in vitro. DCs were isolated from the human peripheral blood monocyte cells (PBMCs of two HLA-A33(+ healthy female volunteers, and infected with adenovirus carrying MGBA cDNA (Ad-MGBA. After that, the Ad-MGBA-infected DCs were used to stimulate CD8(+ CTLs in vitro and the latter was used for co-culture with breast cancer cell lines. The data revealed that infection with Ad-MGBA improved DC maturation and up-regulated the expression of co-stimulatory molecules and the secretion of interleukin-12 (IL-12, but down-regulated interleukin-10 (IL-10 secretion from DCs. Ad-MGBA-infected DC-stimulated CD8(+CTLs displayed the highest cytotoxicity towards HLA-A33(+/MGBA(+ breast cancer MDA-MB-415 cells compared with other CD8(+CTL populations, and compared with the cytotoxicity towards HLA-A33(-/MGBA(+ breast cancer HBL-100 cells and HLA-A33(-/MGBA(- breast cancer MDA-MB 231 cells. In addition, Ad-MGBA-infected DC-stimulated CD8(+ CTLs showed a high level of IFNγ secretion when stimulated with HLA-A33(+/MGBA(+ breast cancer MDA-MB-415 cells, but not when stimulated with HLA-A33(-/MGBA(+ HBL-100 and HLA-A33(-/MGBA(-MDA-MB-231 cells. In addition, killing of CD8(+CTLs against breast cancer was in a major histocompability complex (MHC-limited pattern. Finally, the data also determined the importance of TNF-α in activating DCs and T cells. These data together suggest that MGBA recombinant adenovirus-infected DCs could induce specific anti-tumor immunity

  5. Clonorchis sinensis-derived total protein attenuates airway inflammation in murine asthma model by inducing regulatory T cells and modulating dendritic cell functions

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Young-Il [Div. of Malaria and Parasitic Diseases, Korea Centers for Disease Control and Prevention, Osong (Korea, Republic of); Kim, Seung Hyun [Div. of AIDS, National Institute of Health, Korea Centers for Disease Control and Prevention, Osong (Korea, Republic of); Ju, Jung Won; Cho, Shin Hyeong; Lee, Won Ja [Div. of Malaria and Parasitic Diseases, Korea Centers for Disease Control and Prevention, Osong (Korea, Republic of); Park, Jin Wook; Park, Yeong-Min [Dept. of Microbiology and Immunology, College of Medicine, Pusan National University, Yang-San (Korea, Republic of); Lee, Sang Eun, E-mail: ondalgl@cdc.go.kr [Div. of Malaria and Parasitic Diseases, Korea Centers for Disease Control and Prevention, Osong (Korea, Republic of)

    2011-04-22

    Highlights: {yields} Treatment with Clonorchis sinensis-derived total protein attenuates OVA-induced airway inflammation and AHR to methacholine. {yields} Induction of CD4{sup +}CD25{sup +}Foxp3{sup +} T cells and IL-10 along with suppression of splenocyte proliferation by C. sinensis-derived total protein. {yields} C. sinensis-derived total protein interferes with the expression of co-stimulatory molecules in DCs. -- Abstract: Asthma is characterized by Th2-mediated inflammation, resulting in airway hyperresponsiveness (AHR) through airway remodeling. Recent epidemiological and experimental reports have suggested an inverse relationship between the development of allergy and helminth infections. Infection by Clonorchis sinensis, a liver fluke that resides in the bile duct of humans, is endemic predominantly in Asia including Korea and China. Using a murine model for asthma, we investigated the effects of C. sinensis-derived total protein (Cs-TP) on allergen-induced airway inflammation and the mechanism underlying the protective effects of Cs-TP administration on asthma. Treatment with Cs-TP attenuated OVA-induced airway inflammation and methacholine-induced AHR, as well as eosinophilia development, lymphocyte infiltration into the lung, and goblet cell metaplasia. This protective effect of Cs-TP is associated with markedly reduced OVA-specific IgE and Th1/Th2 cytokine production. Moreover, Cs-TP increased the number of CD4{sup +}CD25{sup +}Foxp3{sup +} regulatory T (Treg) cells as well as their suppressive activity. In fact, proliferation of OVA-restimulated splenocytes was suppressed significantly. Cs-TP also inhibited the expression of such co-stimulatory molecules as CD80, CD86, and CD40 in LPS- or OVA-stimulated dendritic cells (DCs), suggesting that Cs-TP could interfere with the capacity of airway DCs to prime naive T cells. These data demonstrate the capacity of C. sinensis to ameliorate allergic asthma and broaden our understanding of the paradoxical

  6. Semaphorin 7A Promotes Chemokine-Driven Dendritic Cell Migration

    NARCIS (Netherlands)

    van Rijn, Anoek; Paulis, Leonie; te Riet, Joost; Vasaturo, Angela; Reinieren-Beeren, Inge; van der Schaaf, Alie; Kuipers, Arthur J.; Schulte, Luuk P.; Jongbloets, Bart C.; Pasterkamp, R. Jeroen; Figdor, Carl G.; van Spriel, Annemiek B.; Buschow, Sonja I.

    2016-01-01

    Dendritic cell (DC) migration is essential for efficient host defense against pathogens and cancer, as well as for the efficacy of DC-based immunotherapies. However, the molecules that induce the migratory phenotype of DCs are poorly defined. Based on a largescale proteome analysis of maturing DCs,

  7. Interaction of classical swine fever virus with dendritic cells

    NARCIS (Netherlands)

    Carrasco, C.P.; Rigden, R.C.; Vincent, I.E.; Balmelli, C.; Ceppi, M.; Bauhofer, O.; Tache, V.; Hjertner, B.; McNeilly, F.; Gennip, van H.G.P.; McCullough, K.C.; Summerfield, A.

    2004-01-01

    Functional disruption of dendritic cells (DCs) is an important strategy for viral pathogens to evade host defences. Monocytotropic viruses such as classical swine fever virus (CSFV) could employ such a mechanism, since the virus can suppress immune responses and induce apoptosis without infecting ly

  8. Molecular Characterization of Dendritic Cell-Derived Exosomes

    OpenAIRE

    Théry, Clotilde; Regnault, Armelle; Garin, Jérôme; Wolfers, Joseph; Zitvogel, Laurence; Ricciardi-Castagnoli, Paola; Raposo, Graça; Amigorena, Sebastian

    1999-01-01

    Exosomes are membrane vesicles secreted by hematopoietic cells upon fusion of late multivesicular endosomes with the plasma membrane. Dendritic cell (DC)-derived exosomes induce potent antitumor immune responses in mice, resulting in the regression of established tumors (Zitvogel, L., A. Regnault, A. Lozier, J. Wolfers, C. Flament, D. Tenza, P. Ricciardi-Castagnoli, G. Raposo, and S. Amigorena. 1998. Nat. Med. 4:594–600). To unravel the molecular basis of exosome-induced immune stimulation, w...

  9. The role of dendritic cells in cancer

    DEFF Research Database (Denmark)

    Hansen, Morten; Andersen, Mads Hald

    2017-01-01

    Though present in low numbers, dendritic cells (DCs) are recognized as major players in the control of cancer by adaptive immunity. The roles of cytotoxic CD8+ T-cells and Th1 helper CD4+ T-cells are well-documented in murine models of cancer and associated with a profound prognostic impact when...... treatment regimens against cancer....

  10. Dendritic cells in peripheral tolerance and immunity

    DEFF Research Database (Denmark)

    Gad, Monika; Claesson, Mogens Helweg; Pedersen, Anders Elm

    2003-01-01

    Dendritic cells capable of influencing immunity exist as functionally distinct subsets, T cell-tolerizing and T cell-immunizing subsets. The present paper reviews how these subsets of DCs develop, differentiate and function in vivo and in vitro at the cellular and molecular level. In particular...

  11. Haemophilus ducreyi lipooligosaccharides induce expression of the immunosuppressive enzyme indoleamine 2,3-dioxygenase via type I interferons and tumor necrosis factor alpha in human dendritic cells.

    Science.gov (United States)

    Li, Wei; Katz, Barry P; Spinola, Stanley M

    2011-08-01

    Haemophilus ducreyi causes chancroid, a genital ulcer disease. In human inoculation experiments, most volunteers fail to clear the bacteria despite the infiltration of innate and adaptive immune cells to the infected sites. The immunosuppressive protein indoleamine 2,3-dioxygenase (IDO) is a rate-limiting enzyme in the L-tryptophan-kynurenine metabolic pathway. Tryptophan depletion and tryptophan metabolites contribute to pathogen persistence by inhibiting T cell proliferation, inducing T cell apoptosis, and promoting the expansion of FOXP3(+) regulatory T (Treg) cells. We previously found that FOXP3(+) Treg cells are enriched in experimental lesions and that H. ducreyi induced IDO transcription in dendritic cells (DC) derived from blood of infected volunteers who developed pustules. Here, we showed that enzymatically active IDO was induced in DC by H. ducreyi. Neutralizing antibodies against interferon alpha/beta receptor 2 chain (IFNAR2) and tumor necrosis factor alpha (TNF-α) inhibited IDO induction. Inhibitors of the mitogen-activated protein kinase (MAPK) p38 and nuclear factor-κB (NF-κB) also inhibited IDO expression. Neither bacterial contact with nor uptake by DC was required for IDO activation. H. ducreyi culture supernatant and H. ducreyi lipooligosaccharides (LOS) induced IDO expression, which required type I interferons, TNF-α, and the three MAPK (p38, c-Jun N-terminal kinase, and extracellular signal regulated kinase) and NF-κB pathways. In addition, LOS-induced IFN-β activated the JAK-STAT pathway. Blocking the LOS/Toll-like receptor 4 (TLR4) signaling pathway greatly reduced H. ducreyi-induced IDO production. These findings indicate that H. ducreyi-induced IDO expression in DC is largely mediated by LOS via type I interferon- and TNF-α-dependent mechanisms and the MAPK, NF-κB, and JAK-STAT pathways.

  12. Effects of dendritic cell-activated and cytokine-induced killer cell therapy on 22 children with acute myeloid leukemia after chemotherapy.

    Science.gov (United States)

    Bai, Yan; Zheng, Jin-e; Wang, Nan; Cai, He-hua; Zhai, Li-na; Wu, Yao-hui; Wang, Fang; Jin, Run-ming; Zhou, Dong-feng

    2015-10-01

    The efficiency of dendritic cell-activated and cytokine-induced killer cell (DC-CIK) therapy on children with acute myeloid leukemia (AML) after chemotherapy was investigated. Mononuclear cells were collected from children achieving complete remission after chemotherapy, cultured in vitro and transfused back into the same patient. Interleukin-2 (IL-2) was injected subcutaneously every other day 10 times at the dose of 1 × 10(6) units. Peripheral blood lymphocyte subsets and minimal residual disease (MRD) were detected by flow cytometry. Function of bone marrow was monitored by methods of morphology, immunology, cytogenetics and molecular biology. The side effects were also observed during the treatment. The average follow-up period for all the 22 patients was 71 months and relapse occurred in two AML patients (9.1%). The percentage of CD3(+)/CD8(+) cells in peripheral blood of 15 patients at the 3rd month after DC-CIK treatment (36.73% ± 12.51%) was dramatically higher than that before treatment (29.20% ± 8.34%, P 0.1% in 5 patients before the treatment, and became lower than 0.1% 3 months after the treatment. During the transfusion of DC-CIK, side effects including fever, chills and hives appeared in 7 out of 22 (31.82%) cases but disappeared quickly after symptomatic treatments. There were no changes in electrocardiography and liver-renal functions after the treatment. MRD in children with AML can be eliminated by DC-CIK therapy which is safe and has fewer side effects.

  13. O-phospho-l-serine mediates hyporesponsiveness toward FVIII in hemophilia A-murine model by inducing tolerogenic properties in dendritic cells.

    Science.gov (United States)

    Fathallah, Anas M; Ramakrishnan, Radha; Balu-Iyer, Sathy V

    2014-11-01

    The clinical use of therapeutic proteins can be complicated by the development of anti-product antibodies. We have previously observed that O-phospho-l-serine (OPLS) reduced antibody response to FVIII in Hemophilia-A (HA) mice. However, the mechanism underlying this observation is not clear. We hypothesize that OPLS reduces immunogenicity by inducing tolerogenic properties in dendritic cells (DCs). We tested this hypothesis using in vivo, in vitro, and ex vivo methods. Naive HA mice that were pre-exposed to FVIII in the presence of OPLS showed substantially lower antibody response following rechallenge with OPLS free FVIII as compared with dexamethasone-pretreated mice. Exposure of OPLS to bone-marrow-derived dendritic cells (BMDCs) in culturing conditions resulted in an increase in the regulatory cytokine TGF-β and a decrease in proinflammatory cytokines TNF-α and IL12p70. This was accompanied by a significant reduction in upregulation of costimulatory marker CD40, as measured by flow cytometry. Furthermore, ex vivo matured BMDCs in the presence of FVIII and OPLS failed to elicit a robust immune response in HA mice compared with FVIII-treated BMDCs. Our data suggest that OPLS modulates the immune response by altering the function and maturation of DCs, resulting in the induction of tolerogenic properties. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:3457-3463, 2014.

  14. The major birch pollen allergen Bet v 1 induces different responses in dendritic cells of birch pollen allergic and healthy individuals.

    Directory of Open Access Journals (Sweden)

    Ursula Smole

    Full Text Available Dendritic cells play a fundamental role in shaping the immune response to allergens. The events that lead to allergic sensitization or tolerance induction during the interaction of the major birch pollen allergen Bet v 1 and dendritic cells are not very well studied. Here, we analyzed the uptake of Bet v 1 and the cross-reactive celery allergen Api g 1 by immature monocyte-derived dendritic cells (iMoDCs of allergic and normal donors. In addition, we characterized the allergen-triggered intracellular signaling and transcriptional events. Uptake kinetics, competitive binding, and internalization pathways of labeled allergens by iMoDCs were visualized by live-cell imaging. Surface-bound IgE was detected by immunofluorescence microscopy and flow cytometry. Allergen- and IgE-induced gene expression of early growth response genes and Th1 and Th2 related cytokines and chemokines were analyzed by real-time PCR. Phosporylation of signaling kinases was analyzed by Western blot. Internalization of Bet v 1 by iMoDCs of both donor groups, likely by receptor-mediated caveolar endocytosis, followed similar kinetics. Bet v 1 outcompeted Api g 1 in cell surface binding and uptake. MoDCs of allergic and healthy donors displayed surface-bound IgE and showed a pronounced upregulation of Th2 cytokine- and NFκB-dependent genes upon non-specific Fcε receptor cross-linking. In contrast to these IgE-mediated responses, Bet v 1-stimulation increased transcript levels of the Th2 cytokines IL-4 and IL-13 but not of NFκB-related genes in MoDCs of BP allergic donors. Cells of healthy donors were either unresponsive or showed elevated mRNA levels of Th1-promoting chemokines. Moreover, Bet v 1 was able to induce Erk1/2 and p38 MAPK activation in BP allergics but only a slight p38 activation in normal donors. In conclusion, our data indicate that Bet v 1 favors the activation of a Th2 program only in DCs of BP allergic individuals.

  15. Peptide-pulsed dendritic cells have superior ability to induce immune-mediated tissue destruction compared to peptide with adjuvant.

    Directory of Open Access Journals (Sweden)

    Dilan Dissanayake

    Full Text Available Vaccines for cancer immunotherapy are of interest but in general have not yet achieved the desired therapeutic efficacy in clinical trials. We present here a novel model to evaluate vaccine strategies by following tissue destruction in a transgenic model, where a defined antigen is expressed on pancreatic islets. We found that the transfer of syngeneic antigen-pulsed dendritic cells (DCs resulted in autoimmune cytotoxic T-lymphocyte activation that was not observed following vaccinations that were based on peptides and adjuvants. Importantly, the induction of diabetes by DC transfer is dependent upon the maturation of DCs prior to transfer. Furthermore, diabetes induction only occurred if DCs were pulsed with the immunodominant epitope in addition to at least one other peptide, suggesting greater cytolytic activity upon engagement of multiple T-cell specificities. While the tumor environment undoubtedly will be more complex than healthy tissue, the insights gained through this model provide useful information on variables that can affect CD8-mediated tissue cytolysis in vivo.

  16. Dendritic cell podosome dynamics does not depend on the F-actin regulator SWAP-70.

    Directory of Open Access Journals (Sweden)

    Anne Götz

    Full Text Available In addition to classical adhesion structures like filopodia or focal adhesions, dendritic cells similar to macrophages and osteoclasts assemble highly dynamic F-actin structures called podosomes. They are involved in cellular processes such as extracellular matrix degradation, bone resorption by osteoclasts, and trans-cellular diapedesis of lymphocytes. Besides adhesion and migration, podosomes enable dendritic cells to degrade connective tissue by matrix metalloproteinases. SWAP-70 interacts with RhoGTPases and F-actin and regulates migration of dendritic cells. SWAP-70 deficient osteoclasts are impaired in F-actin-ring formation and bone resorption. In the present study, we demonstrate that SWAP-70 is not required for podosome formation and F-actin turnover in dendritic cells. Furthermore, we found that toll-like receptor 4 ligand induced podosome disassembly and podosome-mediated matrix degradation is not affected by SWAP-70 in dendritic cells. Thus, podosome formation and function in dendritic cells is independent of SWAP-70.

  17. Rabies virus infection induces type I interferon production in an IPS-1 dependent manner while dendritic cell activation relies on IFNAR signaling.

    Science.gov (United States)

    Faul, Elizabeth J; Wanjalla, Celestine N; Suthar, Mehul S; Gale, Michael; Wirblich, Christoph; Schnell, Matthias J

    2010-07-22

    As with many viruses, rabies virus (RABV) infection induces type I interferon (IFN) production within the infected host cells. However, RABV has evolved mechanisms by which to inhibit IFN production in order to sustain infection. Here we show that RABV infection of dendritic cells (DC) induces potent type I IFN production and DC activation. Although DCs are infected by RABV, the viral replication is highly suppressed in DCs, rendering the infection non-productive. We exploited this finding in bone marrow derived DCs (BMDC) in order to differentiate which pattern recognition receptor(s) (PRR) is responsible for inducing type I IFN following infection with RABV. Our results indicate that BMDC activation and type I IFN production following a RABV infection is independent of TLR signaling. However, IPS-1 is essential for both BMDC activation and IFN production. Interestingly, we see that the BMDC activation is primarily due to signaling through the IFNAR and only marginally induced by the initial infection. To further identify the receptor recognizing RABV infection, we next analyzed BMDC from Mda-5-/- and RIG-I-/- mice. In the absence of either receptor, there is a significant decrease in BMDC activation at 12h post infection. However, only RIG-I-/- cells exhibit a delay in type I IFN production. In order to determine the role that IPS-1 plays in vivo, we infected mice with pathogenic RABV. We see that IPS-1-/- mice are more susceptible to infection than IPS-1+/+ mice and have a significantly increased incident of limb paralysis.

  18. Detecting Danger: The Dendritic Cell Algorithm

    CERN Document Server

    Greensmith, Julie; Cayzer, Steve

    2010-01-01

    The Dendritic Cell Algorithm (DCA) is inspired by the function of the dendritic cells of the human immune system. In nature, dendritic cells are the intrusion detection agents of the human body, policing the tissue and organs for potential invaders in the form of pathogens. In this research, and abstract model of DC behaviour is developed and subsequently used to form an algorithm, the DCA. The abstraction process was facilitated through close collaboration with laboratory- based immunologists, who performed bespoke experiments, the results of which are used as an integral part of this algorithm. The DCA is a population based algorithm, with each agent in the system represented as an 'artificial DC'. Each DC has the ability to combine multiple data streams and can add context to data suspected as anomalous. In this chapter the abstraction process and details of the resultant algorithm are given. The algorithm is applied to numerous intrusion detection problems in computer security including the detection of p...

  19. GK-1 Improves the Immune Response Induced by Bone Marrow Dendritic Cells Loaded with MAGE-AX in Mice with Melanoma

    Directory of Open Access Journals (Sweden)

    Gabriela Piñón-Zárate

    2014-01-01

    Full Text Available The aim of dendritic cell (DC vaccination in cancer is to induce tumor-specific effector T cells that may reduce and control tumor mass. Immunostimulants that could drive a desired immune response are necessary to be found in order to generate a long lasting tumor immune response. GK-1 peptide, derived from Taenia crassiceps, induces not only increase in TNFα, IFNγ, and MCP-1 production in cocultures of DCs and T lymphocytes but also immunological protection against influenza virus. Moreover, the aim of this investigation is the use of GK-1 as a bone marrow DCs (BMDCs immunostimulant targeted with MAGE antigen; thus, BMDC may be used as immunotherapy against murine melanoma. GK-1 induced in BMDCs a meaningful increment of CD86 and IL-12. In addition, the use of BMDCs TNFα/GK-1/MAGE-AX induced the highest survival and the smallest tumors in mice. Besides, the treatment helped to increase CD8 lymphocytes levels and to produce IFNγ in lymph nodes. Moreover, the histopathological analysis showed that BMDCs treated with GK-1/TNFα and loaded with MAGE-AX induced the apparition of more apoptotic and necrotic areas in tumors than in mice without treatment. These results highlight the properties of GK-1 as an immunostimulant of DCs and suggest as a potential candidate the use of this immunotherapy against cancer disease.

  20. GK-1 improves the immune response induced by bone marrow dendritic cells loaded with MAGE-AX in mice with melanoma.

    Science.gov (United States)

    Piñón-Zárate, Gabriela; Herrera-Enríquez, Miguel Ángel; Hernández-Téllez, Beatriz; Jarquín-Yáñez, Katia; Castell-Rodríguez, Andrés Eliú

    2014-01-01

    The aim of dendritic cell (DC) vaccination in cancer is to induce tumor-specific effector T cells that may reduce and control tumor mass. Immunostimulants that could drive a desired immune response are necessary to be found in order to generate a long lasting tumor immune response. GK-1 peptide, derived from Taenia crassiceps, induces not only increase in TNFα, IFNγ, and MCP-1 production in cocultures of DCs and T lymphocytes but also immunological protection against influenza virus. Moreover, the aim of this investigation is the use of GK-1 as a bone marrow DCs (BMDCs) immunostimulant targeted with MAGE antigen; thus, BMDC may be used as immunotherapy against murine melanoma. GK-1 induced in BMDCs a meaningful increment of CD86 and IL-12. In addition, the use of BMDCs TNFα/GK-1/MAGE-AX induced the highest survival and the smallest tumors in mice. Besides, the treatment helped to increase CD8 lymphocytes levels and to produce IFNγ in lymph nodes. Moreover, the histopathological analysis showed that BMDCs treated with GK-1/TNFα and loaded with MAGE-AX induced the apparition of more apoptotic and necrotic areas in tumors than in mice without treatment. These results highlight the properties of GK-1 as an immunostimulant of DCs and suggest as a potential candidate the use of this immunotherapy against cancer disease.

  1. Enhanced antigen uptake by dendritic cells induced by the B pentamer of the type II heat-labile enterotoxin LT-IIa requires engagement of TLR2.

    Science.gov (United States)

    Lee, Chang Hoon; Nawar, Hesham F; Mandell, Lorrie; Liang, Shuang; Hajishengallis, George; Connell, Terry D

    2010-05-07

    The potent mucosal adjuvant properties of the type II heat-labile enterotoxin LT-IIa of Escherichia coli are dependent upon binding of the B pentamer of the enterotoxin (LT-IIa-B(5)) to ganglioside receptors on immunocompetent cells. To evaluate the immunomodulatory activities of LT-IIa-B(5), in vitro experiments employing bone marrow-derived dendritic cells (BMDC) were performed. Uptake of OVA-FITC, a model antigen (Ag), was enhanced by treatment of BMDC with LT-IIa-B5, but not by treatment of cells with the B pentamer of cholera toxin (CTB). Expression of co-stimulatory molecules (CD40, CD80, CD86, and MHC-II) and cytokines (IL-12p40, TNF-alpha, and IFN-gamma) was increased in BMDC treated with LT-IIa-B(5). The capacity of LT-IIa-B(5) to enhance Ag uptake and to induce expression of co-stimulatory receptors and cytokines by BMDC was dependent upon expression of TLR2 by the cell. Increased Ag uptake induced by LT-IIa-B(5) was correlated with increased Ag-specific proliferation of CD4(+) T cells in an in vitro syngeneic DO11.10 CD4(+) T cell proliferation assay. These experiments confirm that LT-IIa-B(5) exhibits potent immunomodulatory properties which may be exploitable as a non-toxic mucosal adjuvant.

  2. ISOLATION OF CHICKEN FOLLICULAR DENDRITIC CELLS

    Science.gov (United States)

    The aim of the present study was to isolate chicken follicular dendritic cells (FDC). A combination of methods involving panning, iodixanol density gradient centrifugation, and magnetic cell separation technology made it possible to obtain functional FDC from the cecal tonsils from chickens, which h...

  3. Infection of Dendritic Cells by the Maedi-Visna Lentivirus

    OpenAIRE

    Ryan, Susanna; Tiley, Laurence; McConnell, Ian; Blacklaws, Barbara

    2000-01-01

    The early stages of lentivirus infection of dendritic cells have been studied in an in vivo model. Maedi-visna virus (MVV) is a natural pathogen of sheep with a tropism for macrophages, but the infection of dendritic cells has not been proven, largely because of the difficulties of definitively distinguishing the two cell types. Afferent lymphatic dendritic cells from sheep have been phenotypically characterized and separated from macrophages. Dendritic cells purified from experimentally infe...

  4. In Situ Observation of Cell-to-Dendrite Transition

    Institute of Scientific and Technical Information of China (English)

    PAN Xiu-Hong; HONG Yong; JIN Wei-Qing

    2005-01-01

    @@ The cell-to-dendrite transition of succinonitrile melt suspended on a loop-shaped Pt heater is observed in real time by a differential interference microscope coupled with Schlieren technique. The transition is divided into two parts: a dendrite coalition process and a subsequent dendrite elimination process. Firstly the dendrites from the same cell are united into a single dendrite. Secondly the competitive growth of dendrites from different cells leads to the elimination of dendrites. The two processes can be understood when involving crystallographic orientation. In addition, the tip velocity and primary spacing of a cell/dendrite are also measured. It turns out that the primary spacing has a significant jump, whereas the growth velocity has no abrupt change during the cell-to-dendrite transition.

  5. Inducible expression of endomorphins in murine dendritic cells★

    OpenAIRE

    Yang, Xiaohuai; Xia, Hui; Chen, Yong; Liu, Xiaofen; Zhou, Cheng; Gao, Qin; Li, Zhenghong

    2012-01-01

    Bone marrow precursor cells were extracted from C57BL/6J mice aged 7–8 weeks, and dendritic cells were purified using anti-CD11c (a specific marker for dendritic cells) antibody-coated magnetic beads. Immunofluorescence staining revealed that the expression levels of endomorphin-1 and endomorphin-2 were upregulated in dendritic cells activated by lipopolysaccharide. An enzyme immunoassay showed that lipopolysaccharide and other Toll-like receptor ligands promoted the secretion of endomorphin-...

  6. TLR-4 Cooperates with Dectin-1 and Mannose Receptor to Expand Th17 and Tc17 Cells Induced by Paracoccidioides brasiliensis Stimulated Dendritic Cells

    Directory of Open Access Journals (Sweden)

    Vera Lucia Garcia Calich

    2015-03-01

    Full Text Available The concomitant use of diverse Pattern Recognition Receptors (PRRs by innate immune cells can result in synergistic or inhibitory activities that profoundly influence anti-microbial immunity. Dectin-1 and the Mannose Receptor (MR are C-type Lectin Receptors (CLRs previously reported to cooperate with Toll Like Receptors (TLRs signaling in the initial inflammatory response and in the induction of adaptive Th17 and Tc17 immunity mediated by CD4+ and CD8+ T cells, respectively. The protective immunity against paracoccidioidomycosis, the most prevalent fungal infection of Latin America, was previously shown to be influenced by these T cell subsets motivating us to study the contribution of TLRs, Dectin-1 and MR to the development of Th17/Tc17 immunity. First, curdlan a specific Dectin-1 agonist was used to characterize the influence of this receptor in the proliferative response and Th17/Tc17 differentiation of naïve lymphocytes induced by Paracoccidioides brasiliensis activated dendritic cells (DCs from C57BL/6 mice. Then, WT, Dectin-1-/-, TLR-2-/- and TLR-4-/- DCs treated or untreated with anti-Dectin-1 and anti-MR antibodies were used to investigate the contribution of these receptors in lymphocyte activation and differentiation. We verified that curdlan induces an enhanced lymphocyte proliferation and development of IL-17 producing CD4+ and CD8+ T cells. In addition, treatment of WT, TLR-2-/- and TLR-4-/- DCs by anti-Dectin-1 antibodies or antigen presentation by Dectin-1-/- DCs led to decreased lymphoproliferation and impaired Th17 and Tc17 expansion. These responses were also inhibited by anti-MR treatment of DCs, but a synergistic action on Th17/Tc17 differentiation was mediated by TLR-4 and MR. Taken together, our results indicate that diverse TLRs and CLRs are involved in the induction of lymphocyte proliferation and Th17/Tc17 differentiation mediated by P. brasiliensis activated DCs, but a synergist action was restricted to Dectin-1, TLR

  7. Bryostatin-1, a naturally occurring antineoplastic agent, acts as a Toll-like receptor 4 (TLR-4) ligand and induces unique cytokines and chemokines in dendritic cells.

    Science.gov (United States)

    Ariza, Maria Eugenia; Ramakrishnan, Rupal; Singh, Narendra P; Chauhan, Ashok; Nagarkatti, Prakash S; Nagarkatti, Mitzi

    2011-01-07

    Bryostatin-1 (Bryo-1), a natural macrocyclic lactone, is clinically used as an anti-cancer agent. In this study, we demonstrate for the first time that Bryo-1 acts as a Toll-like receptor 4 (TLR4) ligand. Interestingly, activation of bone marrow-derived dendritic cells (in vitro with Bryo-1) led to a TLR4-dependent biphasic activation of nuclear factor-κB (NF-κB) and the unique induction of cytokines (IL-5, IL-6, and IL-10) and chemokines, including RANTES (regulated on activation normal T cell expressed and secreted) and macrophage inflammatory protein 1α (MIP1-α). In addition, EMSA demonstrated that Bryo-1-mediated induction of RANTES was regulated by NF-κB and the interferon regulatory factors (IRF)-1, IRF-3, and IRF-7 to the RANTES independently of myeloid differentiation primary response gene-88 (MyD88). Bryo-1 was able to induce the transcriptional activation of IRF-3 through the TLR4/MD2-dependent pathway. In vivo administration of Bryo-1 triggered a TLR-4-dependent T helper cell 2 (Th2) cytokine response and expanded a subset of myeloid dendritic cells that expressed a CD11c(high)CD8α(-) CD11b(+)CD4(+) phenotype. This study demonstrates that Bryo-1 can act as a TLR4 ligand and activate innate immunity. Moreover, the ability of Bryo-1 to trigger RANTES and MIP1-α suggests that Bryo-1 could potentially be used to prevent HIV-1 infection. Finally, induction of a Th2 response by Bryo-1 may help treat inflammatory diseases mediated by Th1 cells. Together, our studies have a major impact on the clinical use of Bryo-1 as an anti-cancer and immunopotentiating agent.

  8. Clinical applications of dendritic cells-cytokine-induced killer cells mediated immunotherapy for pancreatic cancer: an up-to-date meta-analysis.

    Science.gov (United States)

    Zhang, Yucai; Zhang, Xiaorui; Zhang, Anqi; Li, Ke; Qu, Kai

    2017-01-01

    This study aimed to systematically evaluate the efficacy and safety of dendritic cells-cytokine-induced killer (DC-CIK) cells immunotherapy in treating pancreatic cancer (PC) patients. Data were collected from published articles of clinical trials. Databases including Web of Science, EMBASE, PubMed, Cochrane Library, Wanfang, and CNKI were searched. The main outcome measures in this research included the overall response rate (ORR), disease control rate (DCR), overall survival (OS), patients' quality of life (QoL), immune function, and adverse events. Comparative analysis was conducted between DC-CIK immunotherapy and chemotherapy (combined therapy) and chemotherapy alone. This analysis covered 14 trials with 1,088 PC patients involved. The combined therapy showed advantages over chemotherapy alone in ORR (odds ratio [OR] =1.69, 95% confidence interval [CI] =1.20-2.38, P=0.003), DCR (OR =2.33, 95% CI =1.63-3.33, P<0.00001), OS (1-year OS, OR =3.61, 95% CI =2.41-5.40, P<0.00001; 3-year OS, OR =2.65, 95% CI =1.56-4.50, P=0.0003) and patients' QoL (P<0.01) with statistical significance. After immunotherapy, lymphocyte subsets' percentages of CD3(+) (P<0.00001), CD4(+) (P=0.01), CD3(+)CD56(+) (P<0.00001), and cytokine levels of IFN-γ (P<0.00001) were significantly increased, and the percentages of CD4(+)CD25(+)CD127(low) (P<0.00001) and levels of IL-4 (P<0.0001) were significantly decreased, whereas analysis on CD8(+) (P=0.59) and CD4(+)/CD8(+) ratio (P=0.64) did not show a significant difference. The combination of DC-CIK immunotherapy and chemotherapy is effective for PC treatment, indicated by prolonging the PC patients' survival time, which benefit from reconstructed immune function of patients.

  9. Macrophages, Dendritic Cells, and Regression of Atherosclerosis

    Directory of Open Access Journals (Sweden)

    Jonathan E. Feig

    2012-07-01

    Full Text Available Atherosclerosis is the number one cause of death in the Western world. It results from the interaction between modified lipoproteins and monocyte-derived cells such as macrophages, dendritic cells, T cells, and other cellular elements of the arterial wall. This inflammatory process can ultimately lead to the development of complex lesions, or plaques, that protrude into the arterial lumen. Ultimately, plaque rupture and thrombosis can occur leading to the clinical complications of myocardial infarction or stroke. Although each of the cell types plays roles in the pathogenesis of atherosclerosis, in this review, the focus will be primarily on the monocyte derived cells- macrophages and dendritic cells. The roles of these cell types in atherogenesis will be highlighted. Finally, the mechanisms of atherosclerosis regression as it relates to these cells will be discussed.

  10. Cutting Edge: Plasmacytoid Dendritic Cells Induce IL-10 Production in T Cells via the Delta-Like-4/Notch Axis

    National Research Council Canada - National Science Library

    Kassner, Nadine; Krueger, Manuela; Yagita, Hideo; Dzionek, Andrzej; Hutloff, Andreas; Kroczek, Richard; Scheffold, Alexander; Rutz, Sascha

    2010-01-01

    ...; Miltenyi Biotec, Bergisch Gladbach; and Department of Molecular Immunology, Robert Koch Institute, Berlin, Germany Proinflammatory Th1 cells can produce large amounts of the immunosuppressive cytokine IL-10, thereby facilitating...

  11. Lactobacillus gasseri SBT2055 Induces TGF-β Expression in Dendritic Cells and Activates TLR2 Signal to Produce IgA in the Small Intestine

    Science.gov (United States)

    Ono-Ohmachi, Aiko; Ukibe, Ken; Ogawa, Akihiro; Moriya, Tomohiro; Kadooka, Yukio; Shiozaki, Takuya; Nakagawa, Hisako; Nakayama, Yosuke; Miyazaki, Tadaaki

    2014-01-01

    Probiotic bacteria provide benefits in enhancing host immune responses and protecting against infection. Induction of IgA production by oral administration of probiotic bacteria in the intestine has been considered to be one reason for this beneficial effect, but the mechanisms of the effect are poorly understood. Lactobacillus gasseri SBT2055 (LG2055) is a probiotic bacterium with properties such as bile tolerance, ability to improve the intestinal environment, and it has preventive effects related to abdominal adiposity. In this study, we have found that oral administration of LG2055 induced IgA production and increased the rate of IgA+ cell population in Peyer's patch and in the lamina propria of the mouse small intestine. The LG2055 markedly increased the amount of IgA in a co-culture of B cells and bone marrow derived dendritic cells (BMDC), and TLR2 signal is critical for it. In addition, it is demonstrated that LG2055 stimulates BMDC to promote the production of TGF-β, BAFF, IL-6, and IL-10, all critical for IgA production from B cells. Combined stimulation of B cells with BAFF and LG2055 enhanced the induction of IgA production. Further, TGF-β signal was shown to be critical for LG2055-induced IgA production in the B cell and BMDC co-culture system, but TGF-β did not induce IgA production in a culture of only B cells stimulated with LG2055. Furthermore, TGF-β was critical for the production of BAFF, IL-6, IL-10, and TGF-β itself from LG2055-stimulated BMDC. These results demonstrate that TGF-β was produced by BMDC stimulated with LG2055 and it has an autocrine/paracrine function essential for BMDC to induce the production of BAFF, IL-6, and IL-10. PMID:25144744

  12. Lactobacillus gasseri SBT2055 induces TGF-β expression in dendritic cells and activates TLR2 signal to produce IgA in the small intestine.

    Science.gov (United States)

    Sakai, Fumihiko; Hosoya, Tomohiro; Ono-Ohmachi, Aiko; Ukibe, Ken; Ogawa, Akihiro; Moriya, Tomohiro; Kadooka, Yukio; Shiozaki, Takuya; Nakagawa, Hisako; Nakayama, Yosuke; Miyazaki, Tadaaki

    2014-01-01

    Probiotic bacteria provide benefits in enhancing host immune responses and protecting against infection. Induction of IgA production by oral administration of probiotic bacteria in the intestine has been considered to be one reason for this beneficial effect, but the mechanisms of the effect are poorly understood. Lactobacillus gasseri SBT2055 (LG2055) is a probiotic bacterium with properties such as bile tolerance, ability to improve the intestinal environment, and it has preventive effects related to abdominal adiposity. In this study, we have found that oral administration of LG2055 induced IgA production and increased the rate of IgA(+) cell population in Peyer's patch and in the lamina propria of the mouse small intestine. The LG2055 markedly increased the amount of IgA in a co-culture of B cells and bone marrow derived dendritic cells (BMDC), and TLR2 signal is critical for it. In addition, it is demonstrated that LG2055 stimulates BMDC to promote the production of TGF-β, BAFF, IL-6, and IL-10, all critical for IgA production from B cells. Combined stimulation of B cells with BAFF and LG2055 enhanced the induction of IgA production. Further, TGF-β signal was shown to be critical for LG2055-induced IgA production in the B cell and BMDC co-culture system, but TGF-β did not induce IgA production in a culture of only B cells stimulated with LG2055. Furthermore, TGF-β was critical for the production of BAFF, IL-6, IL-10, and TGF-β itself from LG2055-stimulated BMDC. These results demonstrate that TGF-β was produced by BMDC stimulated with LG2055 and it has an autocrine/paracrine function essential for BMDC to induce the production of BAFF, IL-6, and IL-10.

  13. Lactobacillus gasseri SBT2055 induces TGF-β expression in dendritic cells and activates TLR2 signal to produce IgA in the small intestine.

    Directory of Open Access Journals (Sweden)

    Fumihiko Sakai

    Full Text Available Probiotic bacteria provide benefits in enhancing host immune responses and protecting against infection. Induction of IgA production by oral administration of probiotic bacteria in the intestine has been considered to be one reason for this beneficial effect, but the mechanisms of the effect are poorly understood. Lactobacillus gasseri SBT2055 (LG2055 is a probiotic bacterium with properties such as bile tolerance, ability to improve the intestinal environment, and it has preventive effects related to abdominal adiposity. In this study, we have found that oral administration of LG2055 induced IgA production and increased the rate of IgA(+ cell population in Peyer's patch and in the lamina propria of the mouse small intestine. The LG2055 markedly increased the amount of IgA in a co-culture of B cells and bone marrow derived dendritic cells (BMDC, and TLR2 signal is critical for it. In addition, it is demonstrated that LG2055 stimulates BMDC to promote the production of TGF-β, BAFF, IL-6, and IL-10, all critical for IgA production from B cells. Combined stimulation of B cells with BAFF and LG2055 enhanced the induction of IgA production. Further, TGF-β signal was shown to be critical for LG2055-induced IgA production in the B cell and BMDC co-culture system, but TGF-β did not induce IgA production in a culture of only B cells stimulated with LG2055. Furthermore, TGF-β was critical for the production of BAFF, IL-6, IL-10, and TGF-β itself from LG2055-stimulated BMDC. These results demonstrate that TGF-β was produced by BMDC stimulated with LG2055 and it has an autocrine/paracrine function essential for BMDC to induce the production of BAFF, IL-6, and IL-10.

  14. The probiotic mixture VSL#3 dampens LPS-induced chemokine expression in human dendritic cells by inhibition of STAT-1 phosphorylation.

    Directory of Open Access Journals (Sweden)

    Rob Mariman

    Full Text Available VSL#3, a mixture of 8 different probiotic bacteria, has successfully been used in the clinic to treat Ulcerative Colitis. We previously identified the modulation of chemokines as a major mechanism in the protective effect of the VSL#3 in a mouse model of colitis. This was supported by in vitro studies that implicated a role for VSL#3 in the suppression of LPS-induced chemokine production by mouse bone marrow-derived dendritic cells (DC. Herein, we validated these findings employing human monocyte-derived DC. Stimulation of human DC with LPS, VSL#3, or a combination of both resulted in their maturation, evident from enhanced expression of activation markers on the cell-surface, as well as the induction of various chemokines and cytokines. Interestingly, a set of LPS-induced chemokines was identified that were suppressed by VSL#3. These included CXCL9, CXCL10, CCL2, CCL7, and CCL8. In silico approaches identified STAT-1 as a dominant regulator of these chemokines, and this was confirmed by demonstrating that LPS-induced phosphorylation of this transcription factor was inhibited by VSL#3. This indicates that VSL#3 may contribute to the control of inflammation by selective suppression of STAT-1 induced chemokines.

  15. Collagen I-induced dendritic cells activation is regulated by TNF-alpha production through down-regulation of IRF4.

    Science.gov (United States)

    Poudel, Barun; Ki, Hyeon-Hui; Lee, Young-Mi; Kim, Dae-Ki

    2015-03-01

    Previously we have shown that collagen I enhances the maturation and function of dendritic cells (DCs). Inflammatory mediators such as tumour necrosis factor (TNF)- alpha, interleukin (IL)-1 beta and lipopolysaccharide (LPS) are also known to activate DCs. Here we investigated the involvement of TNF-alpha on the collagen I-induced DCs activation. TNF-a neutralization inhibited collagen I-induced IL-12 secretions by DCs. Additionally, we observed suppression of collagen I-induced costimulatory molecules expression along with down-regulation of genes involved in DCs activation pathway. Furthermore, TNF- alpha inhibition upon collagen Istimulation up-regulated the expression of interferon regulatory transcription factor IRF4, when compared to collagen I only treated cells. Collectively, our data demonstrate that collagen I induce TNF- alpha production, which is crucial for the activation and function of DCs, through down-regulation of IRF4, and implicates the importance in development of anti- TNF-alpha therapeutics for several inflammatory diseases.

  16. Mycobacterium tuberculosis PE25/PPE41 protein complex induces activation and maturation of dendritic cells and drives Th2-biased immune responses.

    Science.gov (United States)

    Chen, Wei; Bao, Yige; Chen, Xuerong; Burton, Jeremy; Gong, Xueli; Gu, Dongqing; Mi, Youjun; Bao, Lang

    2016-04-01

    Mycobacterium tuberculosis evades innate host immune responses by parasitizing macrophages and causes significant morbidity and mortality around the world. A mycobacterial antigen that can activate dendritic cells (DCs) and elicit effective host innate immune responses will be vital to the development of an effective TB vaccine. The M. tuberculosis genes PE25/PPE41 encode proteins which have been associated with evasion of the host immune response. We constructed a PE25/PPE41 complex gene via splicing by overlapping extension and expressed it successfully in E. coli. We investigated whether this protein complex could interact with DCs to induce effective host immune responses. The PE25/PPE41 protein complex induced maturation of isolated mouse DCs in vitro, increasing expression of cell surface markers (CD80, CD86 and MHC-II), thereby promoting Th2 polarization via secretion of pro-inflammatory cytokines IL-4 and IL-10. In addition, PE25/PPE41 protein complex-activated DCs induced proliferation of mouse CD4(+) and CD8(+) T cells, and a strong humoral response in immunized mice. The sera of five TB patients were also highly reactive to this antigen. These findings suggest that interaction of the PE25/PPE41 protein complex with DCs may be of great immunological significance.

  17. Differentiation of apical and basal dendrites in pyramidal cells and granule cells in dissociated hippocampal cultures.

    Science.gov (United States)

    Wu, You Kure; Fujishima, Kazuto; Kengaku, Mineko

    2015-01-01

    Hippocampal pyramidal cells and dentate granule cells develop morphologically distinct dendritic arbors, yet also share some common features. Both cell types form a long apical dendrite which extends from the apex of the cell soma, while short basal dendrites are developed only in pyramidal cells. Using quantitative morphometric analyses of mouse hippocampal cultures, we evaluated the differences in dendritic arborization patterns between pyramidal and granule cells. Furthermore, we observed and described the final apical dendrite determination during dendritic polarization by time-lapse imaging. Pyramidal and granule cells in culture exhibited similar dendritic patterns with a single principal dendrite and several minor dendrites so that the cell types were not readily distinguished by appearance. While basal dendrites in granule cells are normally degraded by adulthood in vivo, cultured granule cells retained their minor dendrites. Asymmetric growth of a single principal dendrite harboring the Golgi was observed in both cell types soon after the onset of dendritic growth. Time-lapse imaging revealed that up until the second week in culture, final principal dendrite designation was not stabilized, but was frequently replaced by other minor dendrites. Before dendritic polarity was stabilized, the Golgi moved dynamically within the soma and was repeatedly repositioned at newly emerging principal dendrites. Our results suggest that polarized growth of the apical dendrite is regulated by cell intrinsic programs, while regression of basal dendrites requires cue(s) from the extracellular environment in the dentate gyrus. The apical dendrite designation is determined from among multiple growing dendrites of young developing neurons.

  18. Generation of Th17 cells in response to intranasal infection requires TGF-β1 from dendritic cells and IL-6 from CD301b+ dendritic cells.

    Science.gov (United States)

    Linehan, Jonathan L; Dileepan, Thamotharampillai; Kashem, Sakeen W; Kaplan, Daniel H; Cleary, Patrick; Jenkins, Marc K

    2015-10-13

    Intranasal (i.n.) infections preferentially generate Th17 cells. We explored the basis for this anatomic preference by tracking polyclonal CD4(+) T cells specific for an MHC class II-bound peptide from the mucosal pathogen Streptococcus pyogenes. S. pyogenes MHC class II-bound peptide-specific CD4(+) T cells were first activated in the cervical lymph nodes following i.n. inoculation and then differentiated into Th17 cells. S. pyogenes-induced Th17 formation depended on TGF-β1 from dendritic cells and IL-6 from a CD301b(+) dendritic cell subset located in the cervical lymph nodes but not the spleen. Thus, the tendency of i.n. infection to induce Th17 cells is related to cytokine production by specialized dendritic cells that drain this site.

  19. Immunization with Dendritic Cells Pulsed ex vivo with Recombinant Chlamydial Protease-Like Activity Factor Induces Protective Immunity Against Genital Chlamydia muridarum Challenge

    Directory of Open Access Journals (Sweden)

    Bernard eArulanandam

    2011-12-01

    Full Text Available We have shown that immunization with soluble recombinant (r chlamydial protease-like activity factor (rCPAF and a T helper (Th 1 type adjuvant can induce significantly enhanced bacterial clearance and protection against Chlamydia–induced pathological sequelae in the genital tract. In this study, we investigated the use of bone marrow derived dendritic cells (BMDCs pulsed ex vivo with rCPAF+CpG in an adoptive subcutaneous immunization for the ability to induce protective immunity against genital chlamydial infection. We found that BMDCs pulsed with rCPAF+CpG efficiently up-regulated the expression of activation markers CD86, CD80, CD40 and major histocompatibility complex class II (MHC II, and secreted interleukin-12, but not IL-10 and IL-4. Mice adoptively immunized with rCPAF+CpG-pulsed BMDCs or UV-EB+CpG-pulsed BMDCs produced elevated levels of antigen-specific IFN- and enhanced IgG1 and IgG2a antibodies. Moreover, mice immunized with rCPAF+CpG-pulsed BMDCs or UV-EB+CpG-pulsed BMDCs exhibited significantly reduced genital Chlamydia shedding, accelerated resolution of infection, and reduced oviduct pathology when compared to infected mock-immunized animals. These results suggest that adoptive subcutaneous immunization with ex vivo rCPAF-pulsed BMDCs is an effective approach, comparable to that induced by UV-EB-BMDCs, for inducing robust anti-Chlamydia immunity.

  20. Dendritic Cells Endocytose Bacillus Anthracis Spores: Implications for Anthrax Pathogenesis

    Science.gov (United States)

    2007-11-02

    Dendritic Cells Endocytose Bacillus anthracis Spores: Implications for Anthrax Pathogenesis1 Katherine C. Brittingham,* Gordon Ruthel,* Rekha G...germination and dissemination of spores. Found in high frequency throughout the respiratory track, dendritic cells (DCs) routinely take up foreign...COVERED - 4. TITLE AND SUBTITLE Dendritic cells endocytose Bacillus anthracis spores: implications for anthrax pathogenesis, The Journal of

  1. Dendritic cells pulsed with alpha-fetoprotein and mutant P53 fused gene induce bi-targeted cytotoxic T lymphocyte response against hepatic carcinoma.

    Science.gov (United States)

    Ren, Jun; Jia, Jun; Zhang, Hongmei; Zhang, Liwang; Ma, Bo; Jiang, Hanfang; Di, Lijun; Song, Guohong; Yu, Jing

    2008-07-01

    Dendritic cell (DC)-based immunotherapy is rapidly emerging as a promising treatment in cancer therapy. We had previously shown that DC pulsed with either defined mRNA of tumor antigen (Ag) such as alpha-fetoprotein (AFP), or total RNA of hepatocellular carcinoma (HCC) could elicit Ag-specific cytotoxic T lymphocyte (CTL) response. Therefore, we suggested a novel DC-based therapeutic method, in which DCs derived from CD34(+) cells enriched peripheral blood mononuclear cells were pulsed with liposome-coated AFP and mutant P53 (mtP53) fused gene pEGFP-C3/AFP-mtP53 to induce bi-targeted specific CTL responses against HCC. Three different genotype HCC cell lines, HepG2 (human histocompatibility leukocyte antigens (HLA) A2 positive, AFP expressing positive, P53 expressing negative), SMMC7721 (HLA A2 positive, neither AFP nor P53 expressing positive), and HMCC97 (HLA A2 positive, both AFP and P53 expressing positive) were selected as targets for CTL responses. An important finding was that DCs pulsed with the liposome-coated fused gene could evoke more intensive bi-targeted Ag-specific CTL responses against HMCC97 than DCs pulsed with either AFP or P53 single gene (P gene of different Ags might induce more extensive multitargeted antitumor immunity.

  2. Ferulic Acid Induces Th1 Responses by Modulating the Function of Dendritic Cells and Ameliorates Th2-Mediated Allergic Airway Inflammation in Mice

    Directory of Open Access Journals (Sweden)

    Chen-Chen Lee

    2015-01-01

    Full Text Available This study investigated the immunomodulatory effects of ferulic acid (FA on antigen-presenting dendritic cells (DCs in vitro and its antiallergic effects against ovalbumin- (OVA- induced Th2-mediated allergic asthma in mice. The activation of FA-treated bone marrow-derived DCs by lipopolysaccharide (LPS stimulation induced a high level of interleukin- (IL- 12 but reduced the expression levels of the proinflammatory cytokines IL-1β, IL-6, and tumor necrosis factor- (TNF- α. Compared to control-treated DCs, FA significantly enhanced the expressions of Notch ligand Delta-like 4 (Dll4, MHC class II, and CD40 molecules by these DCs. Furthermore, these FA-treated DCs enhanced T-cell proliferation and Th1 cell polarization. In animal experiments, oral administration of FA reduced the levels of OVA-specific immunoglobulin E (IgE and IgG1 and enhanced IgG2a antibody production in serum. It also ameliorated airway hyperresponsiveness and attenuated eosinophilic pulmonary infiltration in dose-dependent manners. In addition, FA treatment inhibited the production of eotaxin, Th2 cytokines (IL-4, IL-5, and IL-13, and proinflammatory cytokines but promoted the Th1 cytokine interferon- (IFN- γ production in bronchoalveolar lavage fluid (BALF and the culture supernatant of spleen cells. These findings suggest that FA exhibits an antiallergic effect via restoring Th1/Th2 imbalance by modulating DCs function in an asthmatic mouse model.

  3. Activation-Induced TIM-4 Expression Identifies Differential Responsiveness of Intestinal CD103+ CD11b+ Dendritic Cells to a Mucosal Adjuvant.

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    Kerry L Hilligan

    Full Text Available Macrophage and dendritic cell (DC populations residing in the intestinal lamina propria (LP are highly heterogeneous and have disparate yet collaborative roles in the promotion of adaptive immune responses towards intestinal antigen. Under steady-state conditions, macrophages are efficient at acquiring antigen but are non-migratory. In comparison, intestinal DC are inefficient at antigen uptake but migrate to the mesenteric lymph nodes (mLN where they present antigen to T cells. Whether such distinction in the roles of DC and macrophages in the uptake and transport of antigen is maintained under immunostimulatory conditions is less clear. Here we show that the scavenger and phosphatidylserine receptor T cell Immunoglobulin and Mucin (TIM-4 is expressed by the majority of LP macrophages at steady-state, whereas DC are TIM-4 negative. Oral treatment with the mucosal adjuvant cholera toxin (CT induces expression of TIM-4 on a proportion of CD103+ CD11b+ DC in the LP. TIM-4+ DC selectively express high levels of co-stimulatory molecules after CT treatment and are detected in the mLN a short time after appearing in the LP. Importantly, intestinal macrophages and DC expressing TIM-4 are more efficient than their TIM-4 negative counterparts at taking up apoptotic cells and soluble antigen ex vivo. Taken together, our results show that CT induces phenotypic changes to migratory intestinal DC that may impact their ability to take up local antigens and in turn promote the priming of mucosal immunity.

  4. Dendritic cells transfected with scFv from Mab 7.B12 mimicking original antigen gp43 induces protection against experimental Paracoccidioidomycosis.

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    Karen S Ferreira

    Full Text Available Paracoccidioidomycosis (PCM, endemic in Latin America, is a progressive systemic mycosis caused by Paracoccidioides brasiliensis (P. brasiliensis, which primarily attacks lung tissue. Dendritic cells (DCs are able to initiate a response in naïve T cells, and they also participate in Th-cell education. Furthermore, these cells have been used for therapy in several disease models. Here we transfected DCs with a plasmid (pMAC/PS-scFv encoding a single chain variable fragment (scFv of an anti-Id antibody that is capable of mimicking gp43, the main antigenic component of P. brasiliensis. First, Balb/c mice were immunized subcutaneously with pMAC/PS-scFv and, after seven days, scFv protein was presented to the regional lymph nodes cells. Moreover, we showed that the DCs transfected with scFv were capable of efficiently activating proliferation of total lymph node cells and inducing a decrease in lung infection. Therefore, our results suggested that the use of scFv-transfected DCs may be a promising therapy in the paracoccidioidomycosis (PCM model.

  5. Dendritic cells transfected with scFv from Mab 7.B12 mimicking original antigen gp43 induces protection against experimental Paracoccidioidomycosis.

    Science.gov (United States)

    Ferreira, Karen S; Maranhão, Andrea Q; Garcia, Maria C C; Brígido, Marcelo M; Santos, Suelen S; Lopes, José D; Almeida, Sandro R

    2011-01-07

    Paracoccidioidomycosis (PCM), endemic in Latin America, is a progressive systemic mycosis caused by Paracoccidioides brasiliensis (P. brasiliensis), which primarily attacks lung tissue. Dendritic cells (DCs) are able to initiate a response in naïve T cells, and they also participate in Th-cell education. Furthermore, these cells have been used for therapy in several disease models. Here we transfected DCs with a plasmid (pMAC/PS-scFv) encoding a single chain variable fragment (scFv) of an anti-Id antibody that is capable of mimicking gp43, the main antigenic component of P. brasiliensis. First, Balb/c mice were immunized subcutaneously with pMAC/PS-scFv and, after seven days, scFv protein was presented to the regional lymph nodes cells. Moreover, we showed that the DCs transfected with scFv were capable of efficiently activating proliferation of total lymph node cells and inducing a decrease in lung infection. Therefore, our results suggested that the use of scFv-transfected DCs may be a promising therapy in the paracoccidioidomycosis (PCM) model.

  6. Disrupted lymph node and splenic stroma in mice with induced inflammatory melanomas is associated with impaired recruitment of T and dendritic cells.

    Directory of Open Access Journals (Sweden)

    Saïdi M Soudja

    Full Text Available Migration of dendritic cells (DC from the tumor environment to the T cell cortex in tumor-draining lymph nodes (TDLN is essential for priming naïve T lymphocytes (TL to tumor antigen (Ag. We used a mouse model of induced melanoma in which similar oncogenic events generate two phenotypically distinct melanomas to study the influence of tumor-associated inflammation on secondary lymphoid organ (SLO organization. One tumor promotes inflammatory cytokines, leading to mobilization of immature myeloid cells (iMC to the tumor and SLO; the other does not. We report that inflammatory tumors induced alterations of the stromal cell network of SLO, profoundly altering the distribution of TL and the capacity of skin-derived DC and TL to migrate or home to TDLN. These defects, which did not require tumor invasion, correlated with loss of fibroblastic reticular cells in T cell zones and in impaired production of CCL21. Infiltrating iMC accumulated in the TDLN medulla and the splenic red pulp. We propose that impaired function of the stromal cell network during chronic inflammation induced by some tumors renders spleens non-receptive to TL and TDLN non-receptive to TL and migratory DC, while the entry of iMC into these perturbed SLO is enhanced. This could constitute a mechanism by which inflammatory tumors escape immune control. If our results apply to inflammatory tumors in general, the demonstration that SLO are poorly receptive to CCR7-dependent migration of skin-derived DC and naïve TL may constitute an obstacle for proposed vaccination or adoptive TL therapies of their hosts.

  7. “Dermal dendritic cells” comprise two distinct populations: CD1+ dendritic cells and CD209+ macrophages

    OpenAIRE

    Ochoa,Maria Teresa; Loncaric, Anya; Krutzik, Stephan R.; Becker, Todd C.; Modlin, Robert L.

    2008-01-01

    A key cell type of the resident skin immune system is the dendritic cell, which in normal skin is located in two distinct microanatomical compartments: Langerhans cells (LC) mainly in the epidermis and dermal dendritic cells (DDC) in the dermis. Here, the lineage of dermal dendritic cells was investigated using monoclonal antibodies and immunohistology. We provide evidence that “dermal dendritic cells” comprise at least two major phenotypic populations of dendritic appearing cells: immature D...

  8. Characterization of chicken dendritic cell markers

    Science.gov (United States)

    Animal and Natural Resources Institute, ARS-USDA, Beltsville, MD, USA. New mouse monoclonal antibodies which detect CD80 and CD83 were developed to characterize chicken dendritic cells (DCs). The characteristics of these molecules have been studied in human, swine, ovine, feline, and canine but not ...

  9. Dendritic cell-secreted lipocalin2 induces CD8+ T-cell apoptosis, contributes to T-cell priming and leads to a TH1 phenotype.

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    Melanie Floderer

    Full Text Available Lipocalin 2 (LCN2, which is highly expressed by dendritic cells (DCs when treated with dexamethasone (Dex and lipopolysaccharide (LPS, plays a key role in the defence against bacteria and is also involved in the autocrine apoptosis of T-cells. However, the function of LCN2 when secreted by DCs is unknown: this is a critical gap in our understanding of the regulation of innate and adaptive immune systems. Tolerance, stimulation and suppression are functions of DCs that facilitate the fine-tuning of the immune responses and which are possibly influenced by LCN2 secretion. We therefore examined the role of LCN2 in DC/T-cell interaction. WT or Lcn2-/- bone marrow-derived DCs were stimulated with LPS or LPS+IFN-γ with and without Dex and subsequently co-cultured with T-cells from ovalbumin-specific TCR transgenic (OT-I and OT-II mice. We found that CD8+ T-cell apoptosis was highly reduced when Lcn2-/- DCs were compared with WT. An in vivo CTL assay, using LPS-treated DCs, showed diminished killing ability in mice that had received Lcn2-/- DCs compared with WT DCs. As a consequence, we analysed T-cell proliferation and found that LCN2 participates in T-cell-priming in a dose-dependent manner and promotes a TH1 microenvironment. DC-secreted LCN2, whose function has previously been unknown, may in fact have an important role in regulating the balance between TH1 and TH2. Our results yield insights into DC-secreted LCN2 activity, which could play a pivotal role in cellular immune therapy and in regulating immune responses.

  10. E6 and E7 fusion immunoglobulin from human papilloma virus 16 induces dendritic cell maturation and antigen specific activation of T helper 1 response.

    Science.gov (United States)

    Kim, Sang-Hoon; Hur, Yu Jin; Lee, Suk Jun; Kim, Sang Joon; Park, Chung-Gyu; Oh, Yu-Koung; Jung, Woon-Won; Seo, Jong Bok; Nam, Myung Hee; Choi, Inho; Chun, Taehoon

    2011-04-01

    Human papilloma virus (HPV) 16 causes cervical cancer. Induction of oncogenesis by HPV 16 is primarily dependent on the function of E6 and E7 proteins, which inactivate the function of p53 and pRB, respectively. Thus, blocking the activity of the E6 and E7 proteins from HPV 16 is critical to inhibiting oncogenesis during infection. We have expressed and purified soluble HPV 16 E6 and E7 fusion immunoglobulin (Ig), which were combined with the constant region of an Ig heavy chain, in a mammalian system. To assess whether soluble E6 and E7 fusion Igs induce effective cellular immune responses, immature dendritic cells (DCs) were treated with these fusion proteins. Soluble E6 and E7 fusion Igs effectively induced maturation of DCs. Furthermore, immunization with soluble E6 and E7 fusion Igs in mice resulted in antigen-specific activation of T helper 1 (Th1) cells. This is the first comprehensive study to show the molecular basis of how soluble HPV 16 E6 or E7 fusion Igs induces Th1 responses through the maturation of DCs. In addition, we show that DC therapy using soluble HPV E6 and E7 fusion Igs may be a valuable tool for controlling the progress of cervical cancer.

  11. CTLA-4 blockade during dendritic cell based booster vaccination influences dendritic cell survival and CTL expansion

    DEFF Research Database (Denmark)

    Pedersen, Anders E; Ronchese, Franca

    2007-01-01

    Dendritic cells (DCs) are potent antigen-presenting cells and critical for the priming of CD8+ T cells. Therefore the use of these cells as adjuvant cells has been tested in a large number of experimental and clinical vaccination studies, in particular cancer vaccine studies. A number of protocols...

  12. Mycobacterium avium subspecies impair dendritic cell maturation.

    Science.gov (United States)

    Basler, Tina; Brumshagen, Christina; Beineke, Andreas; Goethe, Ralph; Bäumer, Wolfgang

    2013-10-01

    Mycobacterium avium ssp. paratuberculosis (MAP) causes Johne's disease, a chronic, granulomatous enteritis of ruminants. Dendritic cells (DC) of the gut are ideally placed to combat invading mycobacteria; however, little is known about their interaction with MAP. Here, we investigated the interaction of MAP and the closely related M. avium ssp. avium (MAA) with murine DC and the effect of infected macrophages on DC maturation. The infection of DC with MAP or MAA induced DC maturation, which differed to that of LPS as maturation was accompanied by higher production of IL-10 and lower production of IL-12. Treatment of maturing DC with supernatants from mycobacteria-infected macrophages resulted in impaired DC maturation, leading to a semi-mature, tolerogenic DC phenotype expressing low levels of MHCII, CD86 and TNF-α after LPS stimulation. Though the cells were not completely differentiated they responded with an increased IL-10 and a decreased IL-12 production. Using recombinant cytokines we provide evidence that the semi-mature DC phenotype results from a combination of secreted cytokines and released antigenic mycobacterial components of the infected macrophage. Our results indicate that MAP and MAA are able to subvert DC function directly by infecting and indirectly via the milieu created by infected macrophages.

  13. Deciphering dendritic cell heterogenity in immunity

    Directory of Open Access Journals (Sweden)

    Michaël eChopin

    2012-02-01

    Full Text Available Dendritic cells (DCs are specialized antigen presenting cells that are exquisitely adapted to sense pathogens and induce the development of adaptive immune responses. They form a complex network of phenotypically and functionally distinct subsets. Within this network, individual DC subsets display highly specific roles in local immunosurveillance, migration and antigen presentation. This division of labor amongst DCs offers great potential to tune the immune response by harnessing subset-specific attributes of DCs in the clinical setting. Until recently, our understanding of DC subsets has been limited and paralleled by poor clinical translation and efficacy. We have now begun to unravel how different DC subsets develop within a complex multilayered system. These finding open up exciting possibilities for targeted manipulation of DC subsets. Furthermore, ground-breaking developments overcoming a major translational obstacle – identification of similar DC populations in mouse and man – now set the stage for significant advances in the field. Here we explore the determinants that underpin cellular and transcriptional heterogeneity within the DC network, how these influence DC distribution and localization at steady-state, and the capacity of DCs to present antigens via direct or cross-presentation during pathogen infection.

  14. Transcriptional regulation of dendritic cell diversity.

    Science.gov (United States)

    Chopin, Michaël; Allan, Rhys S; Belz, Gabrielle T

    2012-01-01

    Dendritic cells (DCs) are specialized antigen presenting cells that are exquisitely adapted to sense pathogens and induce the development of adaptive immune responses. They form a complex network of phenotypically and functionally distinct subsets. Within this network, individual DC subsets display highly specific roles in local immunosurveillance, migration, and antigen presentation. This division of labor amongst DCs offers great potential to tune the immune response by harnessing subset-specific attributes of DCs in the clinical setting. Until recently, our understanding of DC subsets has been limited and paralleled by poor clinical translation and efficacy. We have now begun to unravel how different DC subsets develop within a complex multilayered system. These findings open up exciting possibilities for targeted manipulation of DC subsets. Furthermore, ground-breaking developments overcoming a major translational obstacle - identification of similar DC populations in mouse and man - now sets the stage for significant advances in the field. Here we explore the determinants that underpin cellular and transcriptional heterogeneity within the DC network, how these influence DC distribution and localization at steady-state, and the capacity of DCs to present antigens via direct or cross-presentation during pathogen infection.

  15. Clinical reagents of GM-CSF and IFN-α induce the generation of functional chronic myeloid leukemia dendritic cells in vitro.

    Science.gov (United States)

    Weng, Kaizhi; Xie, Xiaobao; Qiu, Guoqiang; Gu, Weiying

    2012-01-01

    Dendritic cells (DCs) have been successfully induced in vitro from chronic myeloid leukemia (CML) cells, which may provide a promising immunotherapeutic protocol for CML. To facilitate the optimization of DCs-based vaccination protocols, we investigated the efficiency of in vitro generation of DCs from bone marrow mononuclear cells of CML patients by clinical reagents of GM-CSF and IFN-α. Bone marrow mononuclear cells were isolated from eight CML patients and CML-DCs were generated in the presence of different cytokines (Group A: GM-CSF for research and IL-4 for research; Group B: GM-CSF for injection and IFN-α for injection) in RMPI-1640 medium containing 10% human AB serum. After 8 days, the morphologic features of CML-DCs were observed and their immunophenotypes were analyzed by flow cytometry. The activity of CML-DCs was determined by evaluating their ability to stimulate allogeneic mixed lymphocyte reaction (allo-MLR) and anti-leukemic cytotoxic T lymphocytes (CTLs). The culture protocols were successful in generating functional CML-DCs from all the CML patients as evidenced by the significant upregulation of CD80, CD86, CD83 HLA-DR and CD1a compared to pre-cultured (p cell stimulating proliferation capacity (p protocols for CML patients.

  16. Targeting vaccines to dendritic cells

    DEFF Research Database (Denmark)

    Foged, Camilla; Sundblad, Anne; Hovgaard, Lars

    2002-01-01

    to be far superior to that of B-cells and macrophages. DC are localized at strategic places in the body at sites used by pathogens to enter the organism, and are thereby in an optimal position to capture antigens. In general, vaccination strategies try to mimic the invasiveness of the pathogens. DC...... are considered to play a central role for the provocation of primary immune responses by vaccination. A rational way of improving the potency and safety of new and already existing vaccines could therefore be to direct vaccines specifically to DC. There is a need for developing multifunctional vaccine drug...... delivery systems (DDS) with adjuvant effect that target DC directly and induce optimal immune responses. This paper will review the current knowledge of DC physiology as well as the progress in the field of novel vaccination strategies that directly or indirectly aim at targeting DC....

  17. Fast generation of dendritic cells

    DEFF Research Database (Denmark)

    Kvistborg, P; Bøgh, Marie; Claesson, M H

    2009-01-01

    we have developed fast DC protocol by comparing two different fast DC protocols with SDDC. DC were evaluated by FACS analysis, and the optimal profile was considered: CD14(low), CD80(high), CD83(high), CD86(high), CCR7(high), HLA class I and II(high). FACS profiles were used as the selection criteria...... together with yield and morphology. Two fast DC protocols fulfilled these criteria and were selected for functional analysis. Our results demonstrate that DC generated within 5days or 48h are comparable with SDDC both phenotypically and functionally. However, we found that 48h DC were more susceptible than...... SDDC to the IL-10 inducing stimulus of TLR ligands (R848 and LPS). Thus to determine the clinical relevance of fast DC protocols in cancer settings, small phase I trials should be conducted monitoring regulatory T cells carefully....

  18. Dendritic Cell Apoptosis and the Pathogenesis of Dengue

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    Lysangela R. Alves

    2012-11-01

    Full Text Available Dengue viruses and other members of the Flaviviridae family are emerging human pathogens. Dengue is transmitted to humans by Aedes aegypti female mosquitoes. Following infection through the bite, cells of the hematopoietic lineage, like dendritic cells, are the first targets of dengue virus infection. Dendritic cells (DCs are key antigen presenting cells, sensing pathogens, processing and presenting the antigens to T lymphocytes, and triggering an adaptive immune response. Infection of DCs by dengue virus may induce apoptosis, impairing their ability to present antigens to T cells, and thereby contributing to dengue pathogenesis. This review focuses on general mechanisms by which dengue virus triggers apoptosis, and possible influence of DC-apoptosis on dengue disease severity.

  19. Dextromethorphan Inhibits Activations and Functions in Dendritic Cells

    Directory of Open Access Journals (Sweden)

    Der-Yuan Chen

    2013-01-01

    Full Text Available Dendritic cells (DCs play an important role in connecting innate and adaptive immunity. Thus, DCs have been regarded as a major target for the development of immunomodulators. In this study, we examined the effect of dextromethorphan (DXM, a common cough suppressant with a high safety profile, on the activation and function of DCs. In the presence of DXM, the LPS-induced expression of the costimulatory molecules in murine bone marrow-derived dendritic cells (BMDCs was significantly suppressed. In addition, DXM treatment reduced the production of reactive oxygen species (ROS, proinflammatory cytokines, and chemokines in maturing BMDCs that were activated by LPS. Therefore, DXM abrogated the ability of LPS-stimulated DCs to induce Ag-specific T-cell activation, as determined by their decreased proliferation and IFN-γ secretion in mixed leukocyte cultures. Moreover, the inhibition of LPS-induced MAPK activation and NF-κB translocation may contribute to the suppressive effect of DXM on BMDCs. Remarkably, DXM decreased the LPS-induced surface expression of CD80, CD83, and HLA-DR and the secretion of IL-6 and IL-12 in human monocyte-derived dendritic cells (MDDCs. These findings provide a new insight into the impact of DXM treatment on DCs and suggest that DXM has the potential to be used in treating DC-related acute and chronic diseases.

  20. Dextromethorphan Inhibits Activations and Functions in Dendritic Cells

    Science.gov (United States)

    Chen, Der-Yuan; Song, Pei-Shan; Hong, Jau-Shyong; Chu, Ching-Liang; Pan, I-Horng; Chen, Yi-Ming; Lin, Ching-Hsiung; Lin, Sheng-Hao; Lin, Chi-Chen

    2013-01-01

    Dendritic cells (DCs) play an important role in connecting innate and adaptive immunity. Thus, DCs have been regarded as a major target for the development of immunomodulators. In this study, we examined the effect of dextromethorphan (DXM), a common cough suppressant with a high safety profile, on the activation and function of DCs. In the presence of DXM, the LPS-induced expression of the costimulatory molecules in murine bone marrow-derived dendritic cells (BMDCs) was significantly suppressed. In addition, DXM treatment reduced the production of reactive oxygen species (ROS), proinflammatory cytokines, and chemokines in maturing BMDCs that were activated by LPS. Therefore, DXM abrogated the ability of LPS-stimulated DCs to induce Ag-specific T-cell activation, as determined by their decreased proliferation and IFN-γ secretion in mixed leukocyte cultures. Moreover, the inhibition of LPS-induced MAPK activation and NF-κB translocation may contribute to the suppressive effect of DXM on BMDCs. Remarkably, DXM decreased the LPS-induced surface expression of CD80, CD83, and HLA-DR and the secretion of IL-6 and IL-12 in human monocyte-derived dendritic cells (MDDCs). These findings provide a new insight into the impact of DXM treatment on DCs and suggest that DXM has the potential to be used in treating DC-related acute and chronic diseases. PMID:23781253

  1. The Attenuated Brucella abortus Strain 19 Invades, Persists in, and Activates Human Dendritic Cells, and Induces the Secretion of IL-12p70 but Not IL-23.

    Directory of Open Access Journals (Sweden)

    Mario Weinhold

    Full Text Available Bacterial vectors have been proposed as novel vaccine strategies to induce strong cellular immunity. Attenuated strains of Brucella abortus comprise promising vector candidates since they have the potential to induce strong CD4(+ and CD8(+ T-cell mediated immune responses in the absence of excessive inflammation as observed with other Gram-negative bacteria. However, some Brucella strains interfere with the maturation of dendritic cells (DCs, which is essential for antigen-specific T-cell priming. In the present study, we investigated the interaction of human monocyte-derived DCs with the smooth attenuated B. abortus strain (S 19, which has previously been employed successfully to vaccinate cattle.We first looked into the potential of S19 to hamper the cytokine-induced maturation of DCs; however, infected cells expressed CD25, CD40, CD80, and CD86 to a comparable extent as uninfected, cytokine-matured DCs. Furthermore, S19 activated DCs in the absence of exogeneous stimuli, enhanced the expression of HLA-ABC and HLA-DR, and was able to persist intracellularly without causing cytotoxicity. Thus, DCs provide a cellular niche for persisting brucellae in vivo as a permanent source of antigen. S19-infected DCs produced IL-12/23p40, IL-12p70, and IL-10, but not IL-23. While heat-killed bacteria also activated DCs, soluble mediators were not involved in S19-induced activation of human DCs. HEK 293 transfectants revealed cellular activation by S19 primarily through engagement of Toll-like receptor (TLR2.Thus, as an immunological prerequisite for vaccine efficacy, B. abortus S19 potently infects and potently activates (most likely via TLR2 human DCs to produce Th1-promoting cytokines.

  2. The Attenuated Brucella abortus Strain 19 Invades, Persists in, and Activates Human Dendritic Cells, and Induces the Secretion of IL-12p70 but Not IL-23

    Science.gov (United States)

    Weinhold, Mario; Eisenblätter, Martin; Jasny, Edith; Fehlings, Michael; Finke, Antje; Gayum, Hermine; Rüschendorf, Ursula; Renner Viveros, Pablo; Moos, Verena; Allers, Kristina; Schneider, Thomas; Schaible, Ulrich E.; Schumann, Ralf R.; Mielke, Martin E.; Ignatius, Ralf

    2013-01-01

    Background Bacterial vectors have been proposed as novel vaccine strategies to induce strong cellular immunity. Attenuated strains of Brucella abortus comprise promising vector candidates since they have the potential to induce strong CD4+ and CD8+ T-cell mediated immune responses in the absence of excessive inflammation as observed with other Gram-negative bacteria. However, some Brucella strains interfere with the maturation of dendritic cells (DCs), which is essential for antigen-specific T-cell priming. In the present study, we investigated the interaction of human monocyte-derived DCs with the smooth attenuated B. abortus strain (S) 19, which has previously been employed successfully to vaccinate cattle. Methodology/Principal findings We first looked into the potential of S19 to hamper the cytokine-induced maturation of DCs; however, infected cells expressed CD25, CD40, CD80, and CD86 to a comparable extent as uninfected, cytokine-matured DCs. Furthermore, S19 activated DCs in the absence of exogeneous stimuli, enhanced the expression of HLA-ABC and HLA-DR, and was able to persist intracellularly without causing cytotoxicity. Thus, DCs provide a cellular niche for persisting brucellae in vivo as a permanent source of antigen. S19-infected DCs produced IL-12/23p40, IL-12p70, and IL-10, but not IL-23. While heat-killed bacteria also activated DCs, soluble mediators were not involved in S19-induced activation of human DCs. HEK 293 transfectants revealed cellular activation by S19 primarily through engagement of Toll-like receptor (TLR)2. Conclusions/Significance Thus, as an immunological prerequisite for vaccine efficacy, B. abortus S19 potently infects and potently activates (most likely via TLR2) human DCs to produce Th1-promoting cytokines. PMID:23805193

  3. Paeonol ameliorates imiquimod-induced psoriasis-like skin lesions in BALB/c mice by inhibiting the maturation and activation of dendritic cells.

    Science.gov (United States)

    Meng, Yujiao; Wang, Mingxing; Xie, Xiangjiang; Di, Tingting; Zhao, Jingxia; Lin, Yan; Xu, Xiaolong; Li, Ningfei; Zhai, Yating; Wang, Yan; Li, Ping

    2017-05-01

    Paeonol, an active component derived from the traditional Chinese medicine Cortex Moutan, possesses anti-inflammatory, analgesic, antioxidant and anti-allergic properties. Psoriasis is a chronic, recurrent, inflammatory dermatosis accompanied by excessive activation of Toll‑like receptors (TLRs) in dendritic cells (DCs), which are primarily responsible for initiating an immune response. We investigated the effect of paeonol on inflammation in an imiquimod (IMQ)-induced psoriasis-like mouse model and murine bone marrow-derived dendritic cells (BMDCs) stimulated by R848. Mice were intragastrically administered 100 mg/kg (high), 50 mg/kg (medium) and 25 mg/kg (low) paeonol, respectively. We evaluated inflammation of psori-asis‑like lesions based on histological changes, protein levels of myeloid differentiation factor 88 (MyD88) and TLR8 in skin lesions by western blotting, and levels of CD11c+ DCs in skin by immunoassay and in spleens by flow cytometry. Inflammatory cytokines [interleukin (IL)-23, IL-12 and IL-1β] in skin lesions and BMDCs were also assessed by RT-PCR and ELISA. Application of paeonol decreased IMQ-induced keratinocyte proliferation, and infiltration of CD3+ cells, while the treatment ameliorated CD11c+ cells in the spleen and skin, and reduced MyD88 and TLR8 proteins in skin lesions. Paeonol inhibited IMQ-induced mRNA expression of IL-23, but not IL-12 and IL-1β in BMDCs, along with significantly lower levels of DCs expressing MHCⅡ, CD80 and CD86 in vitro. These results indicate that paeonol suppresses the maturation and activation of DCs by decreasing MyD88 and TLR8 proteins in the TLR7/8 signaling pathway which finally alleviates psoriasis‑like skin lesions. The TLR7/8 signaling pathway in DCs provides an important insight into the mechanism of psoriasis, and paeonol may be a potent therapeutic drug for psoriasis.

  4. Evaluation on the Clinical Efficacy of Dendritic Cell-Activated Cytokine-Induced Killer Cells Combined with Conventional Therapy in the Treatment of Malignant Tumors

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    Hong WEI

    2016-06-01

    Full Text Available Objective: To evaluate the clinical efficacy of dendritic cell-activated cytokine-induced killer (DC-CIK cells combined with conventional therapy in the treatment of malignant tumors.Methods: A total of 100 patients with malignant tumors were randomly divided into two groups. Treatment group received conventional therapy combined with DC-CIK while control group received conventional therapy alone. The short-term efficacy, adverse reactions and changes of lymphocyte subpopulation were all compared between two groups after treatment.Results: The overall response rate (ORR was higher in treatment group (86.00% than in control group (54.00%, the difference was statistically significant (P<0.05. White blood cell count (WBC reduced after treatment when compared with treatment before (P=0.001, but liver and kidney function had no obvious change in treatment group (P>0.05. WBC reduced markedly, but the level of alanine aminotransferase (ALT increased obviously after treatment in control group (P<0.001. WBC was higher, but the level of ALT was lower in treatment group than in control group (P<0.001. However, there was no difference between two groups regarding serum creatinine (Scr and blood urea nitrogen (BUN (P>0.05. In treatment group, the levels of CD3+, CD3+CD4+, CD3+CD8+, and CD3+CD56+ increased (P<0.05, but the level of CD4+/CD8+ had no significant change (P>0.05. In control group, the levels of CD3+ and CD3+CD4+ reduced (P<0.05, while the levels of CD3+CD8+, CD3+CD56+ and CD4+/CD8+ had no significant change (P>0.05. The levels of CD3+, CD3+CD4+, CD3+CD8+ and CD3+CD56+ in treatment group were higher than those in control group (P<0.01, whereas CD4+/CD8+ was lower than that in control group (P<0.01.Conclusion: DC-CIK combined with conventional therapy, safe and effective, is capable of promoting the recovery of leukocytes and liver and kidney function, and improving the cellular immune function, which may provide a new therapeutic regimen for

  5. Reactive oxygen species are involved in BMP-induced dendritic growth in cultured rat sympathetic neurons.

    Science.gov (United States)

    Chandrasekaran, Vidya; Lea, Charlotte; Sosa, Jose Carlo; Higgins, Dennis; Lein, Pamela J

    2015-07-01

    Previous studies have shown that bone morphogenetic proteins (BMPs) promote dendritic growth in sympathetic neurons; however, the downstream signaling molecules that mediate the dendrite promoting activity of BMPs are not well characterized. Here we test the hypothesis that reactive oxygen species (ROS)-mediated signaling links BMP receptor activation to dendritic growth. In cultured rat sympathetic neurons, exposure to any of the three mechanistically distinct antioxidants, diphenylene iodinium (DPI), nordihydroguaiaretic acid (NGA) or desferroxamine (DFO), blocked de novo BMP-induced dendritic growth. Addition of DPI to cultures previously induced with BMP to extend dendrites caused dendritic retraction while DFO and NGA prevented further growth of dendrites. The inhibition of the dendrite promoting activity of BMPs by antioxidants was concentration-dependent and occurred without altering axonal growth or neuronal cell survival. Antioxidant treatment did not block BMP activation of SMAD 1,5 as determined by nuclear localization of these SMADs. While BMP treatment did not cause a detectable increase in intracellular ROS in cultured sympathetic neurons as assessed using fluorescent indicator dyes, BMP treatment increased the oxygen consumption rate in cultured sympathetic neurons as determined using the Seahorse XF24 Analyzer, suggesting increased mitochondrial activity. In addition, BMPs upregulated expression of NADPH oxidase 2 (NOX2) and either pharmacological inhibition or siRNA knockdown of NOX2 significantly decreased BMP-7 induced dendritic growth. Collectively, these data support the hypothesis that ROS are involved in the downstream signaling events that mediate BMP7-induced dendritic growth in sympathetic neurons, and suggest that ROS-mediated signaling positively modulates dendritic complexity in peripheral neurons.

  6. BCG stimulated dendritic cells induce an interleukin-10 producing T-cell population with no T helper 1 or T helper 2 bias in vitro

    DEFF Research Database (Denmark)

    Madura Larsen, Jeppe; Benn, Christine Stabell; Fillie, Yvonne;

    2007-01-01

    enhanced IL-10 and diminished IL-12 production. These DCs primed naive T cells to develop into IL-10-producing T cells, with no T helper 1 or T helper 2 bias. These results suggest that BCG vaccination might result in the development of IL-10-producing DCs as well as IL-10-producing T cells that could......Mycobacterium bovis bacillus Calmette-Guérin (BCG) vaccine has been associated with beneficial effects on overall childhood mortality in low-income countries; this cannot be explained merely by the prevention of tuberculosis (TB) deaths. The beneficial effects of BCG vaccine could be the result...... of either strengthening of pro-inflammatory mechanisms, helping neonates to fight infections, or the induction of an immune-regulatory network restricting overt inflammation and intense pathology. We aimed to study the effect of live BCG on the ability of dendritic cells (DCs) to polarize T-cell responses...

  7. Dendritic Cells for SYN Scan Detection

    CERN Document Server

    Greensmith, Julie

    2010-01-01

    Artificial immune systems have previously been applied to the problem of intrusion detection. The aim of this research is to develop an intrusion detection system based on the function of Dendritic Cells (DCs). DCs are antigen presenting cells and key to activation of the human immune system, behaviour which has been abstracted to form the Dendritic Cell Algorithm (DCA). In algorithmic terms, individual DCs perform multi-sensor data fusion, asynchronously correlating the the fused data signals with a secondary data stream. Aggregate output of a population of cells, is analysed and forms the basis of an anomaly detection system. In this paper the DCA is applied to the detection of outgoing port scans using TCP SYN packets. Results show that detection can be achieved with the DCA, yet some false positives can be encountered when simultaneously scanning and using other network services. Suggestions are made for using adaptive signals to alleviate this uncovered problem.

  8. First Genomic Analysis of Dendritic Cells from Lung and Draining Lymph Nodes in Murine Asthma

    Directory of Open Access Journals (Sweden)

    Thomas Tschernig

    2015-01-01

    Full Text Available Asthma is the consequence of allergic inflammation in the lung compartments and lung-draining lymph nodes. Dendritic cells initiate and promote T cell response and drive it to immunity or allergy. However, their modes of action during asthma are poorly understood. In this study, an allergic inflammation with ovalbumin was induced in 38 mice versus 42 control animals. After ovalbumin aerosol challenge, conventional dendritic cells (CD11c/MHCII/CD8 were isolated from the lungs and the draining lymph nodes by means of magnetic cell sorting followed by fluorescence-activated cell sorting. A comparative transcriptional analysis was performed using gene arrays. In general, many transcripts are up- and downregulated in the CD8− dendritic cells of the allergic inflamed lung tissue, whereas few genes are regulated in CD8+ dendritic cells. The dendritic cells of the lymph nodes also showed minor transcriptional changes. The data support the relevance of the CD8− conventional dendritic cells but do not exclude distinct functions of the small population of CD8+ dendritic cells, such as cross presentation of external antigen. So far, this is the first approach performing gene arrays in dendritic cells obtained from lung tissue and lung-draining lymph nodes of asthmatic-like mice.

  9. Rabies virus infection induces type I interferon production in an IPS-1 dependent manner while dendritic cell activation relies on IFNAR signaling.

    Directory of Open Access Journals (Sweden)

    Elizabeth J Faul

    Full Text Available As with many viruses, rabies virus (RABV infection induces type I interferon (IFN production within the infected host cells. However, RABV has evolved mechanisms by which to inhibit IFN production in order to sustain infection. Here we show that RABV infection of dendritic cells (DC induces potent type I IFN production and DC activation. Although DCs are infected by RABV, the viral replication is highly suppressed in DCs, rendering the infection non-productive. We exploited this finding in bone marrow derived DCs (BMDC in order to differentiate which pattern recognition receptor(s (PRR is responsible for inducing type I IFN following infection with RABV. Our results indicate that BMDC activation and type I IFN production following a RABV infection is independent of TLR signaling. However, IPS-1 is essential for both BMDC activation and IFN production. Interestingly, we see that the BMDC activation is primarily due to signaling through the IFNAR and only marginally induced by the initial infection. To further identify the receptor recognizing RABV infection, we next analyzed BMDC from Mda-5-/- and RIG-I-/- mice. In the absence of either receptor, there is a significant decrease in BMDC activation at 12h post infection. However, only RIG-I-/- cells exhibit a delay in type I IFN production. In order to determine the role that IPS-1 plays in vivo, we infected mice with pathogenic RABV. We see that IPS-1-/- mice are more susceptible to infection than IPS-1+/+ mice and have a significantly increased incident of limb paralysis.

  10. EBI2 augments Tfh cell fate by promoting interaction with IL-2-quenching dendritic cells.

    Science.gov (United States)

    Li, Jianhua; Lu, Erick; Yi, Tangsheng; Cyster, Jason G

    2016-05-05

    T follicular helper (Tfh) cells are a subset of T cells carrying the CD4 antigen; they are important in supporting plasma cell and germinal centre responses. The initial induction of Tfh cell properties occurs within the first few days after activation by antigen recognition on dendritic cells, although how dendritic cells promote this cell-fate decision is not fully understood. Moreover, although Tfh cells are uniquely defined by expression of the follicle-homing receptor CXCR5 (refs 1, 2), the guidance receptor promoting the earlier localization of activated T cells at the interface of the B-cell follicle and T zone has been unclear. Here we show that the G-protein-coupled receptor EBI2 (GPR183) and its ligand 7α,25-dihydroxycholesterol mediate positioning of activated CD4 T cells at the interface of the follicle and T zone. In this location they interact with activated dendritic cells and are exposed to Tfh-cell-promoting inducible co-stimulator (ICOS) ligand. Interleukin-2 (IL-2) is a cytokine that has multiple influences on T-cell fate, including negative regulation of Tfh cell differentiation. We demonstrate that activated dendritic cells in the outer T zone further augment Tfh cell differentiation by producing membrane and soluble forms of CD25, the IL-2 receptor α-chain, and quenching T-cell-derived IL-2. Mice lacking EBI2 in T cells or CD25 in dendritic cells have reduced Tfh cells and mount defective T-cell-dependent plasma cell and germinal centre responses. These findings demonstrate that distinct niches within the lymphoid organ T zone support distinct cell fate decisions, and they establish a function for dendritic-cell-derived CD25 in controlling IL-2 availability and T-cell differentiation.

  11. TLR4-mediated podosome loss discriminates gram-negative from gram-positive bacteria in their capacity to induce dendritic cell migration and maturation.

    Science.gov (United States)

    van Helden, Suzanne F G; van den Dries, Koen; Oud, Machteld M; Raymakers, Reinier A P; Netea, Mihai G; van Leeuwen, Frank N; Figdor, Carl G

    2010-02-01

    Chronic infections are caused by microorganisms that display effective immune evasion mechanisms. Dendritic cell (DC)-dependent T cell-mediated adaptive immunity is one of the mechanisms that have evolved to prevent the occurrence of chronic bacterial infections. In turn, bacterial pathogens have developed strategies to evade immune recognition. In this study, we show that gram-negative and gram-positive bacteria differ in their ability to activate DCs and that gram-negative bacteria are far more effective inducers of DC maturation. Moreover, we observed that only gram-negative bacteria can induce loss of adhesive podosome structures in DCs, a response necessary for the induction of effective DC migration. We demonstrate that the ability of gram-negative bacteria to trigger podosome turnover and induce DC migration reflects their capacity to selectively activate TLR4. Examining mice defective in TLR4 signaling, we show that this DC maturation and migration are mainly Toll/IL-1 receptor domain-containing adaptor-inducing IFNbeta-dependent. Furthermore, we show that these processes depend on the production of PGs by these DCs, suggesting a direct link between TLR4-mediated signaling and arachidonic metabolism. These findings demonstrate that gram-positive and gram-negative bacteria profoundly differ in their capacity to activate DCs. We propose that this inability of gram-positive bacteria to induce DC maturation and migration is part of the armamentarium necessary for avoiding the induction of an effective cellular immune response and may explain the frequent involvement of these pathogens in chronic infections.

  12. LAB/NTAL facilitates fungal/PAMP-induced IL-12 and IFN-γ production by repressing β-catenin activation in dendritic cells.

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    Selinda J Orr

    2013-05-01

    Full Text Available Fungal pathogens elicit cytokine responses downstream of immunoreceptor tyrosine-based activation motif (ITAM-coupled or hemiITAM-containing receptors and TLRs. The Linker for Activation of B cells/Non-T cell Activating Linker (LAB/NTAL encoded by Lat2, is a known regulator of ITAM-coupled receptors and TLR-associated cytokine responses. Here we demonstrate that LAB is involved in anti-fungal immunity. We show that Lat2-/- mice are more susceptible to C. albicans infection than wild type (WT mice. Dendritic cells (DCs express LAB and we show that it is basally phosphorylated by the growth factor M-CSF or following engagement of Dectin-2, but not Dectin-1. Our data revealed a unique mechanism whereby LAB controls basal and fungal/pathogen-associated molecular patterns (PAMP-induced nuclear β-catenin levels. This in turn is important for controlling fungal/PAMP-induced cytokine production in DCs. C. albicans- and LPS-induced IL-12 and IL-23 production was blunted in Lat2-/- DCs. Accordingly, Lat2-/- DCs directed reduced Th1 polarization in vitro and Lat2-/- mice displayed reduced Natural Killer (NK and T cell-mediated IFN-γ production in vivo/ex vivo. Thus our data define a novel link between LAB and β-catenin nuclear accumulation in DCs that facilitates IFN-γ responses during anti-fungal immunity. In addition, these findings are likely to be relevant to other infectious diseases that require IL-12 family cytokines and an IFN-γ response for pathogen clearance.

  13. Dendritic Cell Cancer Vaccines: From the Bench to the Bedside

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    Tamar Katz

    2014-10-01

    Full Text Available The recognition that the development of cancer is associated with acquired immunodeficiency, mostly against cancer cells themselves, and understanding pathways inducing this immunosuppression, has led to a tremendous development of new immunological approaches, both vaccines and drugs, which overcome this inhibition. Both “passive” (e.g. strategies relying on the administration of specific T cells and “active” vaccines (e.g. peptide-directed or whole-cell vaccines have become attractive immunological approaches, inducing cell death by targeting tumor-associated antigens. Whereas peptide-targeted vaccines are usually directed against a single antigen, whole-cell vaccines (e.g. dendritic cell vaccines are aimed to induce robust responsiveness by targeting several tumor-related antigens simultaneously. The combination of vaccines with new immuno-stimulating agents which target “immunosuppressive checkpoints” (anti-CTLA-4, PD-1, etc. is likely to improve and maintain immune response induced by vaccination.

  14. Receptor-Dependent Coronavirus Infection of Dendritic Cells

    Science.gov (United States)

    Turner, Brian C.; Hemmila, Erin M.; Beauchemin, Nicole; Holmes, Kathryn V.

    2004-01-01

    In several mammalian species, including humans, coronavirus infection can modulate the host immune response. We show a potential role of dendritic cells (DC) in murine coronavirus-induced immune modulation and pathogenesis by demonstrating that the JAW SII DC line and primary DC from BALB/c mice and p/p mice with reduced expression of the murine coronavirus receptor, murine CEACAM1a, are susceptible to murine coronavirus infection by a receptor-dependent pathway. PMID:15113927

  15. A trifunctional dextran-based nanovaccine targets and activates murine dendritic cells, and induces potent cellular and humoral immune responses in vivo.

    Directory of Open Access Journals (Sweden)

    Limei Shen

    Full Text Available Dendritic cells (DCs constitute an attractive target for specific delivery of nanovaccines for immunotherapeutic applications. Here we tested nano-sized dextran (DEX particles to serve as a DC-addressing nanocarrier platform. Non-functionalized DEX particles had no immunomodulatory effect on bone marrow (BM-derived murine DCs in vitro. However, when adsorbed with ovalbumine (OVA, DEX particles were efficiently engulfed by BM-DCs in a mannose receptor-dependent manner. A DEX-based nanovaccine containing OVA and lipopolysaccharide (LPS as a DC stimulus induced strong OVA peptide-specific CD4(+ and CD8(+ T cell proliferation both in vitro and upon systemic application in mice, as well as a robust OVA-specific humoral immune response (IgG1>IgG2a in vivo. Accordingly, this nanovaccine also raised both a more pronounced delayed-type hypersensitivity response and a stronger induction of cytotoxic CD8(+ T cells than obtained upon administration of OVA and LPS in soluble form. Therefore, DEX-based nanoparticles constitute a potent, versatile and easy to prepare nanovaccine platform for immunotherapeutic approaches.

  16. Immunological Characterization of Whole Tumour Lysate-Loaded Dendritic Cells for Cancer Immunotherapy.

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    Veronica Rainone

    Full Text Available Dendritic cells play a key role as initiators of T-cell responses, and even if tumour antigen-loaded dendritic cells can induce anti-tumour responses, their efficacy has been questioned, suggesting a need to enhance immunization strategies.We focused on the characterization of bone marrow-derived dendritic cells pulsed with whole tumour lysate (TAA-DC, as a source of known and unknown antigens, in a mouse model of breast cancer (MMTV-Ras. Dendritic cells were evaluated for antigen uptake and for the expression of MHC class I/II and costimulatory molecules and markers associated with maturation.Results showed that antigen-loaded dendritic cells are characterized by a phenotypically semi-mature/mature profile and by the upregulation of genes involved in antigen presentation and T-cell priming. Activated dendritic cells stimulated T-cell proliferation and induced the production of high concentrations of IL-12p70 and IFN-γ but only low levels of IL-10, indicating their ability to elicit a TH1-immune response. Furthermore, administration of Antigen loaded-Dendritic Cells in MMTV-Ras mice evoked a strong anti-tumour response in vivo as demonstrated by a general activation of immunocompetent cells and the release of TH1 cytokines.Data herein could be useful in the design of antitumoral DC-based therapies, showing a specific activation of immune system against breast cancer.

  17. Inhibition of breast cancer resistance protein (ABCG2 in human myeloid dendritic cells induces potent tolerogenic functions during LPS stimulation.

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    Jun-O Jin

    Full Text Available Breast cancer resistance protein (ABCG2, a member of the ATP-binding cassette transporters has been identified as a major determinant of multidrug resistance (MDR in cancer cells, but ABC transporter inhibition has limited therapeutic value in vivo. In this research, we demonstrated that inhibition of efflux transporters ABCG2 induced the generation of tolerogenic DCs from human peripheral blood myeloid DCs (mDCs. ABCG2 expression was present in mDCs and was further increased by LPS stimulation. Treatment of CD1c+ mDCs with an ABCG2 inhibitor, Ko143, during LPS stimulation caused increased production of IL-10 and decreased production of pro-inflammatory cytokines and decreased expression of CD83 and CD86. Moreover, inhibition of ABCG2 in monocyte-derived DCs (MDDCs abrogated the up-regulation of co-stimulatory molecules and production of pro-inflammatory cytokines in these cells in response to LPS. Furthermore, CD1c+ mDCs stimulated with LPS plus Ko143 inhibited the proliferation of allogeneic and superantigen-specific syngenic CD4+ T cells and promoted expansion of CD25+FOXP3+ regulatory T (Treg cells in an IL-10-dependent fashion. These tolerogenic effects of ABCG2 inhibition could be abolished by ERK inhibition. Thus, we demonstrated that inhibition of ABCG2 in LPS-stimulated mDCs can potently induce tolerogenic potentials in these cells, providing crucial new information that could lead to development of better strategies to combat MDR cancer.

  18. Clinical applications of dendritic cells–cytokine-induced killer cells mediated immunotherapy for pancreatic cancer: an up-to-date meta-analysis

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    Zhang YC

    2017-08-01

    Full Text Available Yucai Zhang,1 Xiaorui Zhang,1 Anqi Zhang,2 Ke Li,2 Kai Qu3 1Department of Health, 2Department of Central Laboratory, Liaocheng People’s Hospital of Taishan Medical University, Liaocheng, Shandong, 3Department of Hepatobiliary Surgery, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi, China Purpose: This study aimed to systematically evaluate the efficacy and safety of dendritic cells–cytokine-induced killer (DC–CIK cells immunotherapy in treating pancreatic cancer (PC patients. Methods: Data were collected from published articles of clinical trials. Databases including Web of Science, EMBASE, PubMed, Cochrane Library, Wanfang, and CNKI were searched. The main outcome measures in this research included the overall response rate (ORR, disease control rate (DCR, overall survival (OS, patients’ quality of life (QoL, immune function, and adverse events. Comparative analysis was conducted between DC–CIK immunotherapy and chemotherapy (combined therapy and chemotherapy alone. Results: This analysis covered 14 trials with 1,088 PC patients involved. The combined therapy showed advantages over chemotherapy alone in ORR (odds ratio [OR] =1.69, 95% confidence interval [CI] =1.20–2.38, P=0.003, DCR (OR =2.33, 95% CI =1.63–3.33, P<0.00001, OS (1-year OS, OR =3.61, 95% CI =2.41–5.40, P<0.00001; 3-year OS, OR =2.65, 95% CI =1.56–4.50, P=0.0003 and patients’ QoL (P<0.01 with statistical significance. After immunotherapy, lymphocyte subsets’ percentages of CD3+ (P<0.00001, CD4+ (P=0.01, CD3+CD56+ (P<0.00001, and cytokine levels of IFN-γ (P<0.00001 were significantly increased, and the percentages of CD4+CD25+CD127low (P<0.00001 and levels of IL-4 (P<0.0001 were significantly decreased, whereas analysis on CD8+ (P=0.59 and CD4+/CD8+ ratio (P=0.64 did not show a significant difference. Conclusion: The combination of DC–CIK immunotherapy and chemotherapy is effective for PC treatment, indicated by prolonging

  19. Crosstalk between dendritic cell subsets and implications for dendritic cell-based anticancer immunotherapy

    NARCIS (Netherlands)

    Bakdash, G.; Schreurs, I.; Schreibelt, G.; Tel, J.

    2014-01-01

    Dendritic cells (DCs) are a family of professional antigen-presenting cells that have an indispensable role in the initiation of innate and adaptive immune responses against pathogens and tumor cells. The DC family is very heterogeneous. Two main types of naturally occurring DCs circulate in periphe

  20. Trypanosoma cruzi down-regulates lipopolysaccharide-induced MHC class I on human dendritic cells and impairs antigen presentation to specific CD8(+) T lymphocytes.

    Science.gov (United States)

    Van Overtvelt, Laurence; Andrieu, Muriel; Verhasselt, Valérie; Connan, Francine; Choppin, Jeannine; Vercruysse, Vincent; Goldman, Michel; Hosmalin, Anne; Vray, Bernard

    2002-10-01

    Trypanosoma cruzi, the etiological agent of Chagas' disease, may persist for many years in its mammalian host. This suggests escape from the immune response and particularly a suboptimal CD8(+) T cell response, since these cells are involved in infection control. In this report, we show that T. cruzi inhibits the lipopolysaccharide (LPS)-induced up-regulation of MHC class I molecules at the surface of human dendritic cells (DC). To further investigate the functional consequences of this inhibition, a trypomastigote surface antigen-derived peptide (TSA-1(514-522) peptide) was selected for its stable binding to HLA-A*0201 molecules and used to generate a primary T. cruzi-specific human CD8(+) T cell line in vitro. We observed that DC infected with T. cruzi or treated with T. cruzi-conditioned medium (TCM) had a weaker capacity to present this peptide to the specific CD8(+) T cell line as shown in an IFN-gamma ELISPOT assay. Interestingly, T. cruzi or TCM also reduced the antigen presentation capacity of DC to CD8(+) T cell lines specific for the influenza virus M(58-66) or HIV RT(476-484) epitopes. This dysfunction appears to be linked essentially to reduced MHC class I molecule expression since the stimulation of the RT(476-484) peptide-specific CD8(+) T cell line was shown to depend mainly on the MHC class I-TCR interaction and not on the co-stimulatory signals which, however, were also inhibited by T. cruzi. This impairment of DC function may represent a novel mechanism reducing in vivo the host's ability to combat efficiently T. cruzi infection.

  1. Dendritic Cells as Danger-Recognizing Biosensors

    Directory of Open Access Journals (Sweden)

    Seokmann Hong

    2009-08-01

    Full Text Available Dendritic cells (DCs are antigen presenting cells that are characterized by a potent capacity to initiate immune responses. DCs comprise several subsets with distinct phenotypes. After sensing any danger(s to the host via their innate immune receptors such as Toll-like receptors, DCs become mature and subsequently present antigens to CD4+ T cells. Since DCs possess the intrinsic capacity to polarize CD4+ helper cells, it is critical to understand the immunological roles of DCs for clinical applications. Here, we review the different DC subsets, their danger-sensing receptors and immunological functions. Furthermore, the cytokine reporter mouse model for studying DC activation is introduced.

  2. Dendritic cell SIRPα regulates homeostasis of dendritic cells in lymphoid organs.

    Science.gov (United States)

    Washio, Ken; Kotani, Takenori; Saito, Yasuyuki; Respatika, Datu; Murata, Yoji; Kaneko, Yoriaki; Okazawa, Hideki; Ohnishi, Hiroshi; Fukunaga, Atsushi; Nishigori, Chikako; Matozaki, Takashi

    2015-06-01

    Signal regulatory protein α (SIRPα), an immunoglobulin superfamily protein that is expressed predominantly in myeloid lineage cells such as dendritic cells (DCs) or macrophages, mediates cell-cell signaling. In the immune system, SIRPα is thought to be important for homeostasis of DCs, but it remains unclear whether SIRPα intrinsic to DCs is indeed indispensable for such functional role. Thus, we here generated the mice, in which SIRPα was specifically ablated in CD11c(+) DCs (Sirpa(Δ) (DC) ). Sirpa(Δ) (DC) mice manifested a marked reduction of CD4(+) CD8α(-) conventional DCs (cDCs) in the secondary lymphoid organs, as well as of Langerhans cells in the epidermis. Such reduction of cDCs in Sirpa(Δ) (DC) mice was comparable to that apparent with the mice, in which SIRPα was systemically ablated. Expression of SIRPα in DCs was well correlated with that of either endothelial cell-selective adhesion molecule (ESAM) or Epstein-Barr virus-induced molecule 2 (EBI2), both of which were also implicated in the regulation of DC homeostasis. Indeed, ESAM(+) or EBI2(+) cDCs were markedly reduced in the spleen of Sirpa(Δ) (DC) mice. Thus, our results suggest that SIRPα intrinsic to CD11c(+) DCs is essential for homeostasis of cDCs in the secondary lymphoid organs and skin.

  3. Improvement of human dendritic cell culture for immunotoxicological investigations.

    Science.gov (United States)

    Hymery, N; Sibiril, Y; Parent-Massin, D

    2006-07-01

    A toxic injury such as a decrease in the number of immature dendritic cells caused by a cytotoxic effect or a disturbance in their maturation process can be responsible for immunodepression. There is a need to improve in vitro assays on human dendritic cells used to detect and evaluate adverse effects of xenobiotics. Two aspects were explored in this work: cytotoxic effects of xenobiotics on immature dendritic cells, and the interference of xenobiotics with dendritic cell maturation. Dendritic cells of two different origins were tested. Dendritic cells obtained either from umbilical cord blood CD34(+) cells or, for the first time, from umbilical cord blood monocytes. The cytotoxicity assay on immature dendritic cells has been improved. For the study of the potential adverse effects of xenobiotics on the maturation process of dendritic cells, several parameters were selected such as expression of markers (CD86, CD83, HLA-DR), secretion of interleukins 10 and 12, and proliferation of autologous lymphocytes. The relevance and the efficiency of the protocol applied were tested using two mycotoxins, T-2 toxin and deoxynivalence, DON, which are known to be immunosuppressive, and one phycotoxin, domoic acid, which is known not to have any immunotoxic effect. Assays using umbilical cord monocyte dendritic cell cultures with the protocol defined in this work, which involves a cytotoxicity study followed by evaluation of several markers of adverse effects on the dendritic cell maturation process, revealed their usefulness for investigating xenobiotic immunotoxicity toward immune primary reactions.

  4. Rapid Exercise-Induced Mobilization of Dendritic Cells Is Potentially Mediated by a Flt3L- and MMP-9-Dependent Process in Multiple Sclerosis

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    Nathalie Deckx

    2015-01-01

    Full Text Available In healthy individuals, one exercise bout induces a substantial increase in the number of circulating leukocytes, while their function is transiently suppressed. The effect of one exercise bout in multiple sclerosis (MS is less studied. Since recent evidence suggests a role of dendritic cells (DC in the pathogenesis of MS, we investigated the effect of one combined endurance/resistance exercise bout on the number and function of DC in MS patients and healthy controls. Our results show a rapid increase in the number of DC in response to physical exercise in both MS patients and controls. Further investigation revealed that in particular DC expressing the migratory molecules CCR5 and CD62L were increased upon acute physical activity. This may be mediated by Flt3L- and MMP-9-dependent mobilization of DC, as demonstrated by increased circulating levels of Flt3L and MMP-9 following one exercise bout. Circulating DC display reduced TLR responsiveness after acute exercise, as evidenced by a less pronounced upregulation of activation markers, HLA-DR and CD86, on plasmacytoid DC and conventional DC, respectively. Our results indicate mobilization of DC, which may be less prone to drive inflammatory processes, following exercise. This may present a negative feedback mechanism for exercise-induced tissue damage and inflammation.

  5. Role of Dendritic Cells in Immune Dysfunction

    Science.gov (United States)

    Savary, Cherylyn A.

    1997-01-01

    Specific aims include: (1) Application of the bioreactor to enhance cytokine-regulated proliferation and maturation of dendritic cells (DC); (2) Based on clues from spaceflight: compare the frequency and function of DC in normal donors and immunocompromised cancer patients; and (3) Initiate studies on the efficiency of cytokine therapy and DC-assisted immunotherapy (using bioreactor-expanded DC) in animal models of experimental fungal infections.

  6. Semiautomated analysis of dendrite morphology in cell culture.

    Science.gov (United States)

    Sweet, Eric S; Langhammer, Chris L; Kutzing, Melinda K; Firestein, Bonnie L

    2013-01-01

    Quantifying dendrite morphology is a method for determining the effect of biochemical pathways and extracellular agents on neuronal development and differentiation. Quantification can be performed using Sholl analysis, dendrite counting, and length quantification. These procedures can be performed on dendrite-forming cell lines or primary neurons grown in culture. In this protocol, we describe the use of a set of computer programs to assist in quantifying many aspects of dendrite morphology, including changes in total and localized arbor complexity.

  7. Immunomodulation with dendritic cells and donor lymphocyte infusion converge to induce graft vs neuroblastoma reactions without GVHD after allogeneic bone marrow transplantation

    OpenAIRE

    Ash, S.; Stein, J.; Askenasy, N; Yaniv, I.

    2010-01-01

    Background: Mounting evidence points to the efficacy of donor lymphocyte infusion (DLI) and immunisation with tumour-pulsed dendritic cells (DC) in generating graft vs leukaemia reactions after allogeneic bone marrow transplantation (BMT). We assessed the efficacy of DLI and DC in generating potent graft vs neuroblastoma tumour (GVT) reactions following allogeneic BMT. Methods: Mice bearing congenic (H2Ka) Neuro-2a tumours were grafted with allogeneic (H2Kb) T-cell-depleted bone marrow cells....

  8. A role for sodium and chloride in kainic acid-induced beading of inhibitory interneuron dendrites.

    Science.gov (United States)

    Al-Noori, S; Swann, J W

    2000-01-01

    Excitotoxic injury of the dendrites of inhibitory interneurons could lead to decreases in their synaptic activation and explain subsequent local circuit hyperexcitability and epilepsy. A hallmark of dendrotoxicity, at least in principal neurons of the hippocampus and cortex, is focal or varicose swellings of dendritic arbors. In experiments reported here, transient (1h) exposure of hippocampal explant cultures to kainic acid produced marked focal swellings of the dendrites of parvalbumin-immunoreactive pyramidal basket cells in a highly reproducible and dose-dependent manner. At 5mM kainic acid, more than half of the immunopositive apical dendrites in area CA(1) had a beaded appearance. However, the somal volumes of these cells were unaltered by the same treatment. The presence of focal swellings was reversible with kainate washout and was not accompanied by interneuronal cell death. In contrast, exposure to much higher concentrations (300mM) of kainic acid resulted in the total loss of parvalbumin-positive interneurons from explants. Surprisingly, kainic acid-induced dendritic beading does not appear to be mediated by extracellular calcium. Beading was unaltered in the presence of N-methyl-D-aspartate receptor antagonists, the L-type calcium channel antagonist, nimodipine, cadmium, or by removing extracellular calcium. However, blockade of voltage-gated sodium channels by either tetrodotoxin or lidocaine abolished dendritic beading, while the activation of existing voltage-gated sodium channels by veratridine mimicked the kainic acid-induced dendritic beading. Finally, the removal of extracellular chloride prevented the kainic acid-induced dendritic beading.Thus, we suggest that the movement of Na(+) and Cl(-), rather than Ca(2+), into cells underlies the focal swellings of interneuron dendrites in hippocampus.

  9. Remodeling of monoplanar Purkinje cell dendrites during cerebellar circuit formation.

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    Megumi Kaneko

    Full Text Available Dendrite arborization patterns are critical determinants of neuronal connectivity and integration. Planar and highly branched dendrites of the cerebellar Purkinje cell receive specific topographical projections from two major afferent pathways; a single climbing fiber axon from the inferior olive that extend along Purkinje dendrites, and parallel fiber axons of granule cells that contact vertically to the plane of dendrites. It has been believed that murine Purkinje cell dendrites extend in a single parasagittal plane in the molecular layer after the cell polarity is determined during the early postnatal development. By three-dimensional confocal analysis of growing Purkinje cells, we observed that mouse Purkinje cells underwent dynamic dendritic remodeling during circuit maturation in the third postnatal week. After dendrites were polarized and flattened in the early second postnatal week, dendritic arbors gradually expanded in multiple sagittal planes in the molecular layer by intensive growth and branching by the third postnatal week. Dendrites then became confined to a single plane in the fourth postnatal week. Multiplanar Purkinje cells in the third week were often associated by ectopic climbing fibers innervating nearby Purkinje cells in distinct sagittal planes. The mature monoplanar arborization was disrupted in mutant mice with abnormal Purkinje cell connectivity and motor discoordination. The dendrite remodeling was also impaired by pharmacological disruption of normal afferent activity during the second or third postnatal week. Our results suggest that the monoplanar arborization of Purkinje cells is coupled with functional development of the cerebellar circuitry.

  10. Loss of interneurons innervating pyramidal cell dendrites and axon initial segments in the CA1 region of the hippocampus following pilocarpine-induced seizures.

    Science.gov (United States)

    Dinocourt, Celine; Petanjek, Zdravko; Freund, Tamas F; Ben-Ari, Yezekiel; Esclapez, Monique

    2003-05-12

    In the pilocarpine model of chronic limbic seizures, vulnerability of GABAergic interneurons to excitotoxic damage has been reported in the hippocampal CA1 region. However, little is known about the specific types of interneurons that degenerate in this region. In order to characterize these interneurons, we performed quantitative analyses of the different populations of GABAergic neurons labeled for their peptide or calcium-binding protein content. Our data demonstrate that the decrease in the number of GAD mRNA-containing neurons in the stratum oriens of CA1 in pilocarpine-treated rats involved two subpopulations of GABAergic interneurons: interneurons labeled for somatostatin only (O-LM and bistratified cells) and interneurons labeled for parvalbumin only (basket and axo-axonic cells). Stratum oriens interneurons labeled for somatostatin/calbindin or somatostatin/parvalbumin were preserved. The decrease in number of somatostatin- and parvalbumin-containing neurons was observed as early as 72 hours after the sustained seizures induced by pilocarpine injection. Many degenerating cell bodies in the stratum oriens and degenerating axon terminals in the stratum lacunosum-moleculare were observed at 1 and 2 weeks after injection. In addition, the synaptic coverage of the axon initial segment of CA1 pyramidal cells was significantly decreased in pilocarpine-treated animals. These results indicate that the loss of somatostatin-containing neurons corresponds preferentially to the degeneration of interneurons with an axon projecting to stratum lacunosum-moleculare (O-LM cells) and suggest that the death of these neurons is mainly responsible for the deficit of dendritic inhibition reported in this region. We demonstrate that the loss of parvalbumin-containing neurons corresponds to the death of axo-axonic cells, suggesting that perisomatic inhibition and mechanisms controlling action potential generation are also impaired in this model.

  11. Antitumor immunopreventive and immunotherapeutic effect in mice induced by hybrid vaccine of dendritic cells and hepatocarcinoma in vivo

    Institute of Scientific and Technical Information of China (English)

    Jin-Kun Zhang; Jun Li; Juan Zhang; Hai-Bin Chen; Su-Biao Chen

    2003-01-01

    AIM: To develop atumor vaccine by fusion of H22 hepatocarcinoma cells and DC, and to study its protective and therapeutical effect against H22 cell.METHODS: H22-DC vaccine was produced by PEG fusion of H22 and DC induced by cytokine released from splenic mononuclear cells, sorted by CD11c magnetic microbead marker. It was injected through the tail vein of the mice and the H22-DC oncogenesis was detected in the liver, spleen and lung. In order to study the therapeutical and protective effect of H22-DC against tumor H22, two groups were divided:immune group and therapeutic group. Immune group was further divided into P, D, HD and H subgroups, immunized by PBS, DC, H22-DC and inactivated H22, respectively, and attacked by H22 cell. The tumor size, tumor weight, mice survival time and tumor latent period were recorded and statistically analyzed; Therapeutical group was divided into three subgroups of P, D and HD, and attacked by H22, then treated with PBS, DC, and H22-DC, respectively. Pathology and flow cytometry were also applied to study the mechanism how the H22-DC vaccine attacked on the H22 cell.RESULTS: 1. No oncogenesis was found in spleen, lung and liver after H22-DC injection. 2. Hybrid vaccine immunized mice had strongest CTL activity. 3. In the immune group,latent period was longer in HD subgroup than that in P, H and D subgroup; and tumor size and weight were smaller in HD subgroup than that in P, H and D subgroup. 4. In therapeutic group, tumor size was smaller in HD subgroup than that in P, D subgroup.CONCLUSION: 1. H22-DC tumor vaccine is safe without oncogenesis in vivo. 2. Hybrid vaccine can stimulate potent specific CTL activity against H22.3. H22-DC vaccine has distinctive prophylatic effect on tumor H22 and can inhibit the tumor growth.

  12. Slit2N/Robo1 inhibit HIV-gp120-induced migration and podosome formation in immature dendritic cells by sequestering LSP1 and WASp.

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    Anil Prasad

    Full Text Available Cell-mediated transmission and dissemination of sexually-acquired human immunodeficiency virus 1 (HIV-1 in the host involves the migration of immature dendritic cells (iDCs. iDCs migrate in response to the HIV-1 envelope protein, gp120, and inhibiting such migration may limit the mucosal transmission of HIV-1. In this study, we elucidated the mechanism of HIV-1-gp120-induced transendothelial migration of iDCs. We found that gp120 enhanced the binding of Wiskott-Aldrich Syndrome protein (WASp and the Actin-Related Protein 2/3 (Arp2/3 complex with β-actin, an interaction essential for the proper formation of podosomes, specialized adhesion structures required for the migration of iDCs through different tissues. We further identified Leukocyte-Specific Protein 1 (LSP1 as a novel component of the WASp-Arp2/3-β-actin complex. Pretreating iDCs with an active fragment of the secretory glycoprotein Slit2 (Slit2N inhibited HIV-1-gp120-mediated migration and podosome formation, by inducing the cognate receptor Roundabout 1 (Robo1 to bind to and sequester WASp and LSP1 from β-actin. Slit2N treatment also inhibited Src signaling and the activation of several downstream molecules, including Rac1, Pyk2, paxillin, and CDC42, a major regulator of podosome formation. Taken together, our results support a novel mechanism by which Slit2/Robo1 may inhibit the HIV-1-gp120-induced migration of iDCs, thereby restricting dissemination of HIV-1 from mucosal surfaces in the host.

  13. α-MSH inhibits TNF-α-induced maturation of human dendritic cells in vitro through the up-regulation of ANXA1

    Institute of Scientific and Technical Information of China (English)

    Yan Min; Deping Han; Zhanjiang Fu; Honghai Wang; Lirong Liu; Yeping Tian

    2011-01-01

    α-Melanocyte-stimulating hormone(α-MSH),an antiinflammatory and immunomodulatory neuropeptide.has been shown to be effective in the experimental treatment of autoimmune diseases and allograft rejection.However,its regulatory mechanism is still unclear.Mature dendritic cells(DCs)are pivotal initiators of immune response and inflammation.We hypothesized that the regulatory role ofα-MSH in DC maturation would contribute to the effects of α-MSH in immune-response-mediated disease models.It was found that α-MSH inhibited tumor necrosis factor-alpha(TNF-α)-induced maturation of human peripheral-monocyte-derived DCs(MoDCs),both phenotypicaily and functionally.This occurred through the down-regulation of the expression of co-stimulatory molecules CD83 and CD86,the production Of IL-12,the promotion Of IL-10secretion,and the MoDC phagocytic activity,suggesting that the inhibition Of DC maturation by α-MSH could contribute to the anti-inflammatory effect Of this neuro-peptide.Furthermore.increased expression of annexin A1(ANXA1)was found to be responsible for the α-MSH inhibiting effect on TNF-α-induced MoDC maturation.which could be abolished by the treatment of MoDCs with specific,small interfering RNAs targeting ANXA1(ANXA1-siRNA),suggesting that α-MSH-induced ANXA1mediates the inhibition.Therefore,α-MSH inhibits TNF-α-induced maturation of human DCs through α-MSH-upregulated ANXAI,suggesting that inhibition of the maturation of DCs by α-MSH could mediate the antiinflammatory effect of the neuropeptide.Furthermore,ANXA1 could be identified as a new therapeutic drug target based on the role Of DCs In immune-mediated Inflammatory diseases.

  14. Dexamethasone Preconditioning Improves the Response of Collagen-Induced Arthritis to Treatment with Short-Term Lipopolysaccharide-Stimulated Collagen-Loaded Dendritic Cells

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    Corina Peña

    2013-01-01

    Full Text Available Background. Pharmacologically modulated dendritic cells (DCs have been shown to restore tolerance in type II collagen-(CII- induced arthritis (CIA. We examined the effect of dexamethasone (DXM administration as a preconditioning agent, followed by an injection of lipopolysaccharide-(LPS- stimulated and CII-loaded DCs on the CIA course. Methods. After CIA induction, mice pretreated with DXM were injected with 4-hour LPS-stimulated DCs loaded with CII (DXM/4hLPS/CII/DCs. Results. Mice injected with DXM/4hLPS/CII/DCs displayed significantly less severe clinical disease compared to animals receiving 4hLPS/CII/DCs alone or those in which only DXM was administered. Cytokine profile evaluation showed that CD4+ T cells from DXM/4hLPS/CII/DCs and 4hLPS/CII/DCs groups release higher IL-10 levels than those from mice receiving DXM alone or CIA mice. CD4+ T cells from all DC-treated groups showed less IL-17 release when compared to the CIA group. On the contrary, CD4+ T cells from DXM/4hLPS/CII/DCs and 4hLPS/CII/DCs groups released higher IFN-γ levels than those from CIA group. Conclusion. A combined treatment, including DXM preconditioning followed by an inoculation of short-term LPS-stimulated CII-loaded DCs, provides an improved strategy for attenuating CIA severity. Our results suggest that this benefit is driven by a modulation in the cytokine profile secreted by CD4+ T cells.

  15. Boosting high-intensity focused ultrasound-induced anti-tumor immunity using a sparse-scan strategy that can more effectively promote dendritic cell maturation

    Directory of Open Access Journals (Sweden)

    Zhong Pei

    2010-01-01

    Full Text Available Abstract Background The conventional treatment protocol in high-intensity focused ultrasound (HIFU therapy utilizes a dense-scan strategy to produce closely packed thermal lesions aiming at eradicating as much tumor mass as possible. However, this strategy is not most effective in terms of inducing a systemic anti-tumor immunity so that it cannot provide efficient micro-metastatic control and long-term tumor resistance. We have previously provided evidence that HIFU may enhance systemic anti-tumor immunity by in situ activation of dendritic cells (DCs inside HIFU-treated tumor tissue. The present study was conducted to test the feasibility of a sparse-scan strategy to boost HIFU-induced anti-tumor immune response by more effectively promoting DC maturation. Methods An experimental HIFU system was set up to perform tumor ablation experiments in subcutaneous implanted MC-38 and B16 tumor with dense- or sparse-scan strategy to produce closely-packed or separated thermal lesions. DCs infiltration into HIFU-treated tumor tissues was detected by immunohistochemistry and flow cytometry. DCs maturation was evaluated by IL-12/IL-10 production and CD80/CD86 expression after co-culture with tumor cells treated with different HIFU. HIFU-induced anti-tumor immune response was evaluated by detecting growth-retarding effects on distant re-challenged tumor and tumor-specific IFN-γ-secreting cells in HIFU-treated mice. Results HIFU exposure raised temperature up to 80 degrees centigrade at beam focus within 4 s in experimental tumors and led to formation of a well-defined thermal lesion. The infiltrated DCs were recruited to the periphery of lesion, where the peak temperature was only 55 degrees centigrade during HIFU exposure. Tumor cells heated to 55 degrees centigrade in 4-s HIFU exposure were more effective to stimulate co-cultured DCs to mature. Sparse-scan HIFU, which can reserve 55 degrees-heated tumor cells surrounding the separated lesions, elicited an

  16. Transcriptional responses of cultured rat sympathetic neurons during BMP-7-induced dendritic growth.

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    Michelle M Garred

    Full Text Available BACKGROUND: Dendrites are the primary site of synapse formation in the vertebrate nervous system; however, relatively little is known about the molecular mechanisms that regulate the initial formation of primary dendrites. Embryonic rat sympathetic neurons cultured under defined conditions extend a single functional axon, but fail to form dendrites. Addition of bone morphogenetic proteins (BMPs triggers these neurons to extend multiple dendrites without altering axonal growth or cell survival. We used this culture system to examine differential gene expression patterns in naïve vs. BMP-treated sympathetic neurons in order to identify candidate genes involved in regulation of primary dendritogenesis. METHODOLOGY/PRINCIPAL FINDINGS: To determine the critical transcriptional window during BMP-induced dendritic growth, morphometric analysis of microtubule-associated protein (MAP-2-immunopositive processes was used to quantify dendritic growth in cultures exposed to the transcription inhibitor actinomycin-D added at varying times after addition of BMP-7. BMP-7-induced dendritic growth was blocked when transcription was inhibited within the first 24 hr after adding exogenous BMP-7. Thus, total RNA was isolated from sympathetic neurons exposed to three different experimental conditions: (1 no BMP-7 treatment; (2 treatment with BMP-7 for 6 hr; and (3 treatment with BMP-7 for 24 hr. Affymetrix oligonucleotide microarrays were used to identify differential gene expression under these three culture conditions. BMP-7 significantly regulated 56 unique genes at 6 hr and 185 unique genes at 24 hr. Bioinformatic analyses implicate both established and novel genes and signaling pathways in primary dendritogenesis. CONCLUSIONS/SIGNIFICANCE: This study provides a unique dataset that will be useful in generating testable hypotheses regarding transcriptional control of the initial stages of dendritic growth. Since BMPs selectively promote dendritic growth in

  17. Targeting vaccines to dendritic cells

    DEFF Research Database (Denmark)

    Foged, Camilla; Sundblad, Anne; Hovgaard, Lars

    2002-01-01

    delivery systems (DDS) with adjuvant effect that target DC directly and induce optimal immune responses. This paper will review the current knowledge of DC physiology as well as the progress in the field of novel vaccination strategies that directly or indirectly aim at targeting DC....

  18. Antigen pulsed CpG-ODN activated dendritic cells induce host-protective immune response by regulating the T regulatory cell functioning in Leishmania donovani-infected mice: critical role of CXCL10

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    Saikat eMajumder

    2014-06-01

    Full Text Available Visceral leishmaniasis (VL, caused by Leishmania donovani, is a systemic infection of reticulo-endothelial system. There is currently no protective vaccine against VL and chemotherapy is increasingly limited due to appearance of drug resistance to first line drugs such as antimonials and amphotericin B. In the present study, by using a murine model of leishmaniasis we evaluated the function played by soluble leishmanial antigen (SLA pulsed-CpG-ODN stimulated dendritic cells (SLA-CpG-DCs in restricting the intracellular parasitic growth. We establish that a single dose of SLA-CpG-DCs vaccination is sufficient in rendering complete protection against Leishmania donovani infection. In probing the possible mechanism, we observed that SLA-CpG-DCs vaccination results in the significant decrease in Foxp3+GITR+CTLA4+CD4+CD25+ Treg cell population in Leishmania-infected mice. Vaccination with these antigen stimulated dendritic cells results in the decrease in the secretion of TGF-β by these Treg cells by possible regulation of the SMAD signalling. Moreover, we demonstrated that a CXC chemokine, IFN-γ-inducible protein 10 (IP-10, has a direct role in the regulation of CD4+CD25+ Treg cells in SLA-CpG-DCs vaccinated parasitized mice as Treg cells isolated from IP-10 depleted vaccinated mice showed significantly increased TGF-β production and suppressive activity.

  19. Natural killer (NK): dendritic cell (DC) cross talk induced by therapeutic monoclonal antibody triggers tumor antigen-specific T cell immunity.

    Science.gov (United States)

    Lee, Steve C; Srivastava, Raghvendra M; López-Albaitero, Andrés; Ferrone, Soldano; Ferris, Robert L

    2011-08-01

    Tumor antigen (TA)-targeted monoclonal antibodies (mAb), trastuzumab, cetuximab, panitumumab, and rituximab, have been among the most successful new therapies in the present generation. Clinical activity is observed as a single agent, or in combination with radiotherapy or chemotherapy, against metastatic colorectal cancer, head and neck cancer, breast cancer, and follicular lymphoma. However, the activity is seen only in a minority of patients. Thus, an intense need exists to define the mechanism of action of these immunoactive mAb. Here, we discuss some of the likely immunological events that occur in treated patients: antibody-dependent cellular cytotoxicity (ADCC), cross talk among immune cells including NK cells and dendritic cells (DCs), and generation of TA-specific T lymphocyte responses. We present evidence supporting the induction of "NK:DC cross talk," leading to priming of TA-specific cellular immunity. These observations show that mAb-mediated NK cell activation can be greatly enhanced by the action of stimulatory cytokines and surface molecules on maturing DC and that NK:DC interaction facilitates the recruitment of both NK cells and DC to the tumor site(s). The cooperative, reciprocal stimulatory activity of both NK cells and DC can modulate both the innate immune response in the local tumor microenvironment and the adaptive immune response in secondary lymphoid organs. These events likely contribute to clinical activity, as well as provide a potential biomarker of response to mAb therapy.

  20. Chemoresistance of human monocyte-derived dendritic cells is regulated by IL-17A.

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    Selma Olsson Åkefeldt

    Full Text Available Dendritic cells initiate adaptive immune responses, leading either to control cancer by effector T cells or to exacerbate cancer by regulatory T cells that inhibit IFN-γ-mediated Th1-type response. Dendritic cells can also induce Th17-type immunity, mediated by IL-17A. However, the controversial role of this cytokine in cancer requires further investigations. We generated dendritic cells from peripheral blood monocytes to investigate lifespan, phenotype and chemoresistance of dendritic cells, treated with IL-17A with or without IFN-γ. Studying the expression of Bcl-2 family members, we demonstrated that dendritic cells constitutively express one pro-survival Bcl-2 member: MCL1. Immature dendritic cells were CD40(lowHLADR(low CD1a(+ MCL1(+, did not express CD14, CD68 or BCL2A1, and displayed a short 2-day lifespan. IL-17A-treated DC exhibited a semi-mature (CD40(high HLADR(low pre-M2 (CCL22(+ CD206(+ CD163(+ IL1RN(+ IL-10(- CXCL10(- IL-12(- mixed (CD1a(+ CD14+ CD68(+ macrophage-dendritic cell phenotype. They efficiently exerted mannose receptor-mediated endocytosis and did not produce superoxide anions, in the absence of TLR engagement. Interestingly, IL-17A promoted a long-term survival of dendritic cells, beyond 12 days, that correlated to BCL2A1 induction, a pro-survival Bcl-2 family member. BCL2A1 transcription was activated by NF-κB, downstream of IL-17A transduction. Thus, immature dendritic cells only express MCL1, whereas IL-17A-treated dendritic cells concomitantly expressed two pro-survival Bcl-2 family members: MCL1 and BCL2A1. These latter developed chemoresistance to 11 of the 17 chemotherapy agents tested. However, high doses of either vinblastine or cytarabine decreased MCL1 expression and induced dendritic cell death. When IL-17A is produced in vivo, administration of anti-IL-17A biotherapy may impair dendritic cell survival by targeting BCL2A1 expression. Consequently, depending on the effector or regulatory role of dendritic

  1. Human XCR1+ Dendritic Cells Derived In Vitro from CD34+ Progenitors Closely Resemble Blood Dendritic Cells, Including Their Adjuvant Responsiveness, Contrary to Monocyte-Derived Dendritic Cells

    OpenAIRE

    S. Balan; Ollion, V.; Colletti, N.; Chelbi, R.; Montanana-Sanchis, F.; LIU, H.; Vu Manh, T.-P.; Sanchez, C.; Savoret, J.; Perrot, I.; Doffin, A.-C.; Fossum, E.; Bechlian, D.; Chabannon, C.; Bogen, B

    2014-01-01

    Human monocyte-derived dendritic cell (MoDC) have been used in the clinic with moderately encouraging results. Mouse XCR1+ DC excel at cross-presentation, can be targeted in vivo to induce protective immunity, and share characteristics with XCR1+ human DC. Assessment of the immunoactivation potential of XCR1+ human DC is hindered by their paucity in vivo and by their lack of a well-defined in vitro counterpart. We report in this study a protocol generating both XCR1+ and XCR1− human DC in CD3...

  2. Human Monocyte-derived Dendritic Cells Pulsed with Wild-field name="type" p53 Protein Efficiently Induce Cytotoxic T-lymphocytes against p53 overexpressing Human Cancer Cells

    OpenAIRE

    德永, 尚之

    2005-01-01

    PURPOSE: Dendritic cells are the most potent antigen-presenting cells for initiating cellular immune responses. Dendritic cells are attractive immunoregulatory cells for cancer immunotherapy, and their efficacy has been investigated in clinical trials. The tumor suppressor gene p53 is pivotal in the regulation of apoptosis, and p53-based immunization is an attractive approach to cancer immunotherapy because of the accumulation of p53 protein in malignant but not in normal cells. It has been s...

  3. Fasciola hepatica tegumental antigens induce anergic-like T cells via dendritic cells in a mannose receptor-dependent manner.

    Science.gov (United States)

    Aldridge, Allison; O'Neill, Sandra M

    2016-05-01

    FoxP3(+) Treg cells and anergic T cells are the two regulatory phenotypes of T-cell responses associated with helminth infection. Here, we examine the T-cell responses in mice during Fasciola hepatica infection, and to its tegumental coat antigens (FhTeg) that are shed from the fluke every 2-3 h. FhTeg comprises a rich source of glycoproteins, mainly oligomannose N-glycans that bind to mannose receptor. This study demonstrated a novel mechanism for the T-cell unresponsiveness observed during F. hepatica infection and after injection with FhTeg. Markers of T-cell anergy, such as GRAIL, EGR2, ICOS, and ITCH, are enhanced amongst CD4(+) T-cell populations during infection and following FhTeg injection. This is characterized by a lack of cytokine responses and reduced proliferative activity, which can be reversed with the addition of IL-2. FhTeg-activated dendritic cells (DCs) suppress T cells in vitro as measured by enhanced GRAIL and CTLA4 by RNA and suppressed cytokine expression in anti-CD3 stimulated CD4(+) T cells. FhTeg-treated DCs have enhanced MR expression, which is critical for DC-CD4(+) T-cell communication. Taken together, this study presents markers of anergy in a mouse model of F. hepatica infection, and improves our understanding of host-pathogen interactions and how helminths modulate host immunity. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Tea Tree (Melaleuca alternifolia) Oil induced Phenotypic and Functional Maturation of Murine Bone Marrow-derived Dendritic Cells%茶树油调控树突状细胞的表型和功能

    Institute of Scientific and Technical Information of China (English)

    唐永富; 李积华; 陈家翠; 林丽静; 韩志萍; 曹玉坡

    2012-01-01

    The effect of tea tree oil on the phenotypic and functional maturation of dendritic cell was investigated in vitro. Dendritic cells treated with tea tree oil (0.005 μL/mL), were enlarged, suspended, and displayed typical stellate and aggregates like cells treated with LPS (positive controls). The levels of surface marker expression were monitored throughout the culture by flow cytometry using CD1 1c-PEcy7, I-Ab-FITC, CD86-FITC, and H-2Db-PE. Dendritic cells treated with tea bee oil expressed higher level of H-2Db (48.20%), costimulatory molecule I-Ab (6.60%) and CD86 (41.00%) with the cells gated by CD11c, being of 1.28,3.40 and 1.28-fold higher for H-2Db, I-Ab and CD86, respectiely compared with untreated cells. It was also found that tea tree oil could enhance the dendritic cell to induce proliferation of T lymphocyte. And it was reduced the endocytic activity of dendritic cell by tea tree oil. These results showed that tea tree oil had significant immunoenhancing activity by inducing the phenotypic and functional maturation of dendritic cells.%本文主要探讨了茶树油对树突状细胞表型和功能的影响.采用茶树油(0.005μL/mL)干预未成熟的树突状细胞48h后,流式细胞仪检测细胞表型,MTT法检测刺激淋巴细胞增殖能力.结果发现经茶树油干预后,以CD11c设门,树突状细胞高表达H-2Db(48.20%),I-Ab(6.60%)和CD86 (41.00%),和空白对照组比较分别达到1.28倍,3.40倍和1.28倍的增长.混合淋巴培养实验发现茶树油能够增强DC刺激淋巴细胞增殖的能力,降低树突状细胞的吞噬功能.初步表明茶树油可以促进树突状细胞的表型和功能成熟.

  5. Dendritic Cells in vivo and in vitro

    Institute of Scientific and Technical Information of China (English)

    Hui Wan; Marcel Dupasquier

    2005-01-01

    Dendritic cells (DC) are crucial cells of the immune system, and bridged the essential connection between innate and adaptive immunity. They reside in the periphery as sentinels where they take up antigens. Upon activation,they migrate to lymphoid organs and present there the processed antigens to T cells, thereby activating them and eliciting a potent immune response. Dendritic cells are bone marrow-derived cells, still big controversies exist about their in vivo development. In vitro, DC can be generated from multiple precursor cells, among them lymphoid and myeloid committed progenitors. Although it remains unknown how DC are generated in vivo,studying the functions of in vitro generated DC results in fundamental knowledge of the DC biology with promising applications for future medicine. Therefore, in this review, we present current protocols for the generation of DC from precursors in vitro. We will do this for the mouse system, where most research occurs and for the human system, where research concentrates on implementing DC biology in disease treatments.

  6. Dendritic Cells in vivo and in vitro

    Institute of Scientific and Technical Information of China (English)

    HuiWan; MarcelDupasquier

    2005-01-01

    Dendritic cells (DC) are crucial cells of the immune system, and bridged the essential connection between innate and adaptive immunity. They reside in the periphery as sentinels where they take up antigens. Upon activation, they migrate to lymphoid organs and present there the processed antigens to T cells, thereby activating them and eliciting a potent immune response. Dendritic cells are bone marrow-derived cells, still big controversies exist about their in vivo development. In vitro, DC can be generated from multiple precursor cells, among them lymphoid and myeloid committed progenitors. Although it remains unknown how DC are generated in vivo, studying the functions of in vitro generated DC results in fundamental knowledge of the DC biology with promising applications for future medicine. Therefore, in this review, we present current protocols for the generation of DC from precursors in vitro. We will do this for the mouse system, where most research occurs and for the human system, where research concentrates on implementing DC biology in disease treatments. Cellular & Molecular Immunology. 2005;2(1):28-35.

  7. Tumour tissue microenvironment can inhibit dendritic cell maturation in colorectal cancer.

    LENUS (Irish Health Repository)

    Michielsen, Adriana J

    2011-01-01

    Inflammatory mediators in the tumour microenvironment promote tumour growth, vascular development and enable evasion of anti-tumour immune responses, by disabling infiltrating dendritic cells. However, the constituents of the tumour microenvironment that directly influence dendritic cell maturation and function are not well characterised. Our aim was to identify tumour-associated inflammatory mediators which influence the function of dendritic cells. Tumour conditioned media obtained from cultured colorectal tumour explant tissue contained high levels of the chemokines CCL2, CXCL1, CXCL5 in addition to VEGF. Pre-treatment of monocyte derived dendritic cells with this tumour conditioned media inhibited the up-regulation of CD86, CD83, CD54 and HLA-DR in response to LPS, enhancing IL-10 while reducing IL-12p70 secretion. We examined if specific individual components of the tumour conditioned media (CCL2, CXCL1, CXCL5) could modulate dendritic cell maturation or cytokine secretion in response to LPS. VEGF was also assessed as it has a suppressive effect on dendritic cell maturation. Pre-treatment of immature dendritic cells with VEGF inhibited LPS induced upregulation of CD80 and CD54, while CXCL1 inhibited HLA-DR. Interestingly, treatment of dendritic cells with CCL2, CXCL1, CXCL5 or VEGF significantly suppressed their ability to secrete IL-12p70 in response to LPS. In addition, dendritic cells treated with a combination of CXCL1 and VEGF secreted less IL-12p70 in response to LPS compared to pre-treatment with either cytokine alone. In conclusion, tumour conditioned media strongly influences dendritic cell maturation and function.

  8. Pharmacological inhibition of eicosanoids and platelet-activating factor signaling impairs zymosan-induced release of IL-23 by dendritic cells.

    Science.gov (United States)

    Rodríguez, Mario; Márquez, Saioa; Montero, Olimpio; Alonso, Sara; Frade, Javier García; Crespo, Mariano Sánchez; Fernández, Nieves

    2016-02-15

    The engagement of the receptors for fungal patterns induces the expression of cytokines, the release of arachidonic acid, and the production of PGE2 in human dendritic cells (DC), but few data are available about other lipid mediators that may modulate DC function. The combined antagonism of leukotriene (LT) B4, cysteinyl-LT, and platelet-activating factor (PAF, 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine) inhibited IL23A mRNA expression in response to the fungal surrogate zymosan and to a lower extent TNFA (tumor necrosis factor-α) and CSF2 (granulocyte macrophage colony-stimulating factor) mRNA. The combination of lipid mediators and the lipid extract of zymosan-conditioned medium increased the induction of IL23A by LPS (bacterial lipopolysaccharide), thus suggesting that unlike LPS, zymosan elicits the production of mediators at a concentration enough for optimal response. Zymosan induced the release of LTB4, LTE4, 12-hydroxyeicosatetraenoic acid (12-HETE), and PAF C16:0. DC showed a high expression and detectable Ser663 phosphorylation of 5-lipoxygenase in response to zymosan, and a high expression and activity of LPCAT1/2 (lysophosphatidylcholine acyltransferase 1 and 2), the enzymes that incorporate acetate from acetyl-CoA into choline-containing lysophospholipids to produce PAF. Pharmacological modulation of the arachidonic acid cascade and the PAF receptor inhibited the binding of P-71Thr-ATF2 (activating transcription factor 2) to the IL23A promoter, thus mirroring their effects on the expression of IL23A mRNA and IL-23 protein. These results indicate that LTB4, cysteinyl-LT, and PAF, acting through their cognate G protein-coupled receptors, contribute to the phosphorylation of ATF2 and play a central role in IL23A promoter trans-activation and the cytokine signature induced by fungal patterns.

  9. Faecalibacterium prausnitzii A2-165 has a high capacity to induce IL-10 in human and murine dendritic cells and modulates T cell responses.

    Science.gov (United States)

    Rossi, Oriana; van Berkel, Lisette A; Chain, Florian; Tanweer Khan, M; Taverne, Nico; Sokol, Harry; Duncan, Sylvia H; Flint, Harry J; Harmsen, Hermie J M; Langella, Philippe; Samsom, Janneke N; Wells, Jerry M

    2016-01-04

    Faecalibacterium prausnitzii strain A2-165 was previously reported to have anti-inflammatory properties and prevent colitis in a TNBS model. We compared the immunomodulatory properties of strain A2-165 to four different F. prausnitzii isolates and eight abundant intestinal commensals using human dendritic cells (DCs) and mouse BMDCs in vitro. Principal component analysis revealed that the cytokine response to F. prausnitzii A2-165 is distinct from the other strains in eliciting high amounts of IL-10 secretion. The mouse DNBS model of relapsing IBD was used to compare the protective effects of F. prausnitzii A2-165 and Clostridium hathewayi, a low secretor of IL-10, on the Th1-driven inflammatory response to DNBS; attenuation of disease parameters was only observed with F. prausnitzii. In an in vivo mouse model of nasal tolerance to ovalbumin, F. prausnitzii A2-165 enhanced ovalbumin-specific T cell proliferation and reduced the proportion of IFN-γ(+) T cells in CLNs. Similarly, in vitro F. prausnitzii A2-165 stimulated BMDCs increased ovalbumin-specific T cell proliferation and reduced the number of IFN-γ(+) T cells. These mechanisms may contribute to the anti-inflammatory effects of F. prausnitzii in colitis and support the notion that this abundant bacterium might contribute to immune homeostasis in the intestine via its anti-inflammatory properties.

  10. Different protein of Echinococcus granulosus stimulates dendritic induced immune response.

    Science.gov (United States)

    Wang, Yana; Wang, Qiang; Lv, Shiyu; Zhang, Shengxiang

    2015-06-01

    Cystic echinococcosis is a chronic infectious disease that results from a host/parasite interaction. Vaccination with ferritin derived from Echinococcus granulosus is a potential preventative treatment. To understand whether ferritin is capable of inducing a host immune response, we investigated the response of dendritic cells (DCs) to both recombinant ferritin protein and the hydatid fluid (HF) of E. granulosus. We evaluated the immunomodulatory potential of these antigens by performing, immunocytochemistry, electron microscopy and in vivo imaging of monocyte-derived murine DCs. During antigen stimulation of DCs, ferritin cause DCs maturation and induced higher levels of surface marker expression and activated T-cell proliferation and migration. On contrary, HF failed to induce surface marker expression and to stimulate T-cell proliferation. In response to HF, DCs produced interleukin-6 (IL-6), but no IL-12 and IL-10. DCs stimulated with ferritin produced high levels of cytokines. Overall, HF appears to induce host immunosuppression in order to ensure parasite survival via inhibits DC maturation and promotes Th2-dependent secretion of cytokines. Although ferritin also promoted DC maturation and cytokine release, it also activates CD4+T-cell proliferation, but regard of the mechanism of the Eg.ferritin induce host to eradicate E. granulosus were not clear.

  11. Mammal-derived respiratory lipocalin allergens do not exhibit dendritic cell-activating capacity.

    Science.gov (United States)

    Parviainen, S; Kinnunen, T; Rytkönen-Nissinen, M; Nieminen, A; Liukko, A; Virtanen, T

    2013-03-01

    Most mammal-derived respiratory allergens belong to the lipocalin family of proteins. Determinants of their allergenic capacity are still unknown. Innate immune cells, in particular dendritic cells, have been shown to be involved in the allergenicity of some proteins. As recognition by dendritic cells is one of the few plausible mechanisms for the allergenicity of proteins, we wanted to investigate their role in the allergenicity of lipocalin allergens. Therefore, we first incubated human monocyte-derived dendritic cells with immunologically functional recombinant allergens mouse Mus m 1, dog Can f 1 and 2, cow Bos d 2, horse Equ c 1 and natural Bos d 2. Then, the surface marker expression and cytokine production of dendritic cells and their capacity to promote T cell proliferation and Th2 immune deviation in naïve CD4(+) T cells were examined in vitro. We found that near to endotoxin-free lipocalin allergens had no effect on the activation, allostimulatory capacity or cytokine production of dendritic cells. The dendritic cells could not induce immune deviation in naïve CD4(+) T cells. In contrast, lipopolysaccharide activated the dendritic cells efficiently. However, lipocalin allergens were not able to modify the lipopolysaccharide-induced responses. We conclude that an important group of mammal-derived respiratory allergens, lipocalins, appear not to be able to activate dendritic cells, a major component involved in the allergenicity of some proteins. It is conceivable that this incapacity of lipocalin allergens to arouse innate immunity may be associated with their poor capacity to induce a strong T cell response, verified in several studies.

  12. Viral piracy: HIV-1 targets dendritic cells for transmission.

    Science.gov (United States)

    Lekkerkerker, Annemarie N; van Kooyk, Yvette; Geijtenbeek, Teunis B H

    2006-04-01

    Dendritic cells (DCs), the professional antigen presenting cells, are critical for host immunity by inducing specific immune responses against a broad variety of pathogens. Remarkably the human immunodeficiency virus-1 (HIV-1) subverts DC function leading to spread of the virus. At an early phase of HIV-1 transmission, DCs capture HIV-1 at mucosal surfaces and transmit the virus to T cells in secondary lymphoid tissues. Capture of the virus on DCs takes place via C-type lectins of which the dendritic cell-specific intercellular adhesion molecule-3 (ICAM-3) grabbing nonintegrin (DC-SIGN) is the best studied. DC-SIGN-captured HIV-1 particles accumulate in CD81(+) multivesicular bodies (MVBs) in DCs and are subsequently transmitted to CD4+ T cells resulting in infection of T cells. The viral cell-to-cell transmission takes place at the DC-T cell interface termed the infectious synapse. Recent studies demonstrate that direct infection of DCs contributes to the transmission to T cells at a later phase. Moreover, the infected DCs may function as cellular reservoirs for HIV-1. This review discusses the different processes that govern viral piracy of DCs by HIV-1, emphasizing the intracellular routing of the virus from capture on the cell surface to egress in the infectious synapse.

  13. Dendritic differentiation of cerebellar Purkinje cells is promoted by ryanodine receptors expressed by Purkinje and granule cells.

    Science.gov (United States)

    Ohashi, Ryo; Sakata, Shin-ichi; Naito, Asami; Hirashima, Naohide; Tanaka, Masahiko

    2014-04-01

    Cerebellar Purkinje cells have the most elaborate dendritic trees among neurons in the brain. We examined the roles of ryanodine receptor (RyR), an intracellular Ca(2+) release channel, in the dendrite formation of Purkinje cells using cerebellar cell cultures. In the cerebellum, Purkinje cells express RyR1 and RyR2, whereas granule cells express RyR2. When ryanodine (10 µM), a blocker of RyR, was added to the culture medium, the elongation and branching of Purkinje cell dendrites were markedly inhibited. When we transferred small interfering RNA (siRNA) against RyR1 into Purkinje cells using single-cell electroporation, dendritic branching but not elongation of the electroporated Purkinje cells was inhibited. On the other hand, transfection of RyR2 siRNA into granule cells also inhibited dendritic branching of Purkinje cells. Furthermore, ryanodine reduced the levels of brain-derived neurotrophic factor (BDNF) in the culture medium. The ryanodine-induced inhibition of dendritic differentiation was partially rescued when BDNF was exogenously added to the culture medium in addition to ryanodine. Overall, these results suggest that RyRs expressed by both Purkinje and granule cells play important roles in promoting the dendritic differentiation of Purkinje cells and that RyR2 expressed by granule cells is involved in the secretion of BDNF from granule cells.

  14. Muscarinic regulation of Kenyon cell dendritic arborizations in adult worker honey bees.

    Science.gov (United States)

    Dobrin, Scott E; Herlihy, J Daniel; Robinson, Gene E; Fahrbach, Susan E

    2011-09-01

    The experience of foraging under natural conditions increases the volume of mushroom body neuropil in worker honey bees. A comparable increase in neuropil volume results from treatment of worker honey bees with pilocarpine, an agonist for muscarinic-type cholinergic receptors. A component of the neuropil growth induced by foraging experience is growth of dendrites in the collar region of the calyces. We show here, via analysis of Golgi-impregnated collar Kenyon cells with wedge arborizations, that significant increases in standard measures of dendritic complexity were also found in worker honey bees treated with pilocarpine. This result suggests that signaling via muscarinic-type receptors promotes the increase in Kenyon cell dendritic complexity associated with foraging. Treatment of worker honey bees with scopolamine, a muscarinic inhibitor, inhibited some aspects of dendritic growth. Spine density on the Kenyon cell dendrites varied with sampling location, with the distal portion of the dendritic field having greater total spine density than either the proximal or medial section. This observation may be functionally significant because of the stratified organization of projections from visual centers to the dendritic arborizations of the collar Kenyon cells. Pilocarpine treatment had no effect on the distribution of spines on dendrites of the collar Kenyon cells.

  15. Helminth Excreted/Secreted Antigens Repress Expression of LPS-Induced Let-7i but Not miR-146a and miR-155 in Human Dendritic Cells

    Directory of Open Access Journals (Sweden)

    Luis I. Terrazas

    2013-01-01

    Full Text Available MicroRNAs have emerged as key regulators of immune responses. They influence immune cells' function and probably the outcome of several infections. Currently, it is largely unknown if helminth parasites and their antigens modify host microRNAs expression. The aim of this study was to explore if excreted/secreted antigens of Taenia crassiceps regulate LPS-induced miRNAs expression in human Dendritic Cells. We found that these antigens repressed LPS-let-7i induction but not mir-146a or mir-155 and this correlates with a diminished inflammatory response. This let-7i downregulation in Dendritic Cells constitutes a novel feature of the modulatory activity that helminth-derived antigens exert on their host.

  16. Activation of Natural Killer T Cells by α-Galactosylceramide Rapidly Induces the Full Maturation of Dendritic Cells In Vivo and Thereby Acts as an Adjuvant for Combined CD4 and CD8 T Cell Immunity to a Coadministered Protein

    Science.gov (United States)

    Fujii, Shin-ichiro; Shimizu, Kanako; Smith, Caroline; Bonifaz, Laura; Steinman, Ralph M.

    2003-01-01

    The maturation of dendritic cells (DCs) allows these antigen-presenting cells to initiate immunity. We pursued this concept in situ by studying the adjuvant action of α-galactosylceramide (αGalCer) in mice. A single i.v. injection of glycolipid induced the full maturation of splenic DCs, beginning within 4 h. Maturation was manifest by marked increases in costimulator and major histocompatibility complex class II expression, interferon (IFN)-γ production, and stimulation of the mixed leukocyte reaction. These changes were not induced directly by αGalCer but required natural killer T (NKT) cells acting independently of the MyD88 adaptor protein. To establish that DC maturation was responsible for the adjuvant role of αGalCer, mice were given αGalCer together with soluble or cell-associated ovalbumin antigen. Th1 type CD4+ and CD8+ T cell responses developed, and the mice became resistant to challenge with ovalbumin-expressing tumor. DCs from mice given ovalbumin plus adjuvant, but not the non-DCs, stimulated ovalbumin-specific proliferative responses and importantly, induced antigen-specific, IFN-γ producing, CD4+ and CD8+ T cells upon transfer into naive animals. In the latter instance, immune priming did not require further exposure to ovalbumin, αGalCer, NKT, or NK cells. Therefore a single dose of αGalCer i.v. rapidly stimulates the full maturation of DCs in situ, and this accounts for the induction of combined Th1 CD4+ and CD8+ T cell immunity to a coadministered protein. PMID:12874260

  17. Activation of natural killer T cells by alpha-galactosylceramide rapidly induces the full maturation of dendritic cells in vivo and thereby acts as an adjuvant for combined CD4 and CD8 T cell immunity to a coadministered protein.

    Science.gov (United States)

    Fujii, Shin-Ichiro; Shimizu, Kanako; Smith, Caroline; Bonifaz, Laura; Steinman, Ralph M

    2003-07-21

    The maturation of dendritic cells (DCs) allows these antigen-presenting cells to initiate immunity. We pursued this concept in situ by studying the adjuvant action of alpha-galactosylceramide (alphaGalCer) in mice. A single i.v. injection of glycolipid induced the full maturation of splenic DCs, beginning within 4 h. Maturation was manifest by marked increases in costimulator and major histocompatibility complex class II expression, interferon (IFN)-gamma production, and stimulation of the mixed leukocyte reaction. These changes were not induced directly by alphaGalCer but required natural killer T (NKT) cells acting independently of the MyD88 adaptor protein. To establish that DC maturation was responsible for the adjuvant role of alphaGalCer, mice were given alphaGalCer together with soluble or cell-associated ovalbumin antigen. Th1 type CD4+ and CD8+ T cell responses developed, and the mice became resistant to challenge with ovalbumin-expressing tumor. DCs from mice given ovalbumin plus adjuvant, but not the non-DCs, stimulated ovalbumin-specific proliferative responses and importantly, induced antigen-specific, IFN-gamma producing, CD4+ and CD8+ T cells upon transfer into naive animals. In the latter instance, immune priming did not require further exposure to ovalbumin, alphaGalCer, NKT, or NK cells. Therefore a single dose of alphaGalCer i.v. rapidly stimulates the full maturation of DCs in situ, and this accounts for the induction of combined Th1 CD4+ and CD8+ T cell immunity to a coadministered protein.

  18. Dendritic Cells under Hypoxia: How Oxygen Shortage Affects the Linkage between Innate and Adaptive Immunity.

    Science.gov (United States)

    Winning, Sandra; Fandrey, Joachim

    2016-01-01

    Dendritic cells (DCs) are considered as one of the main regulators of immune responses. They collect antigens, process them, and present typical antigenic structures to lymphocytes, thereby inducing an adaptive immune response. All these processes take place under conditions of oxygen shortage (hypoxia) which is often not considered in experimental settings. This review highlights how deeply hypoxia modulates human as well as mouse immature and mature dendritic cell functions. It tries to link in vitro results to actual in vivo studies and outlines how hypoxia-mediated shaping of dendritic cells affects the activation of (innate) immunity.

  19. Dendritic Cells under Hypoxia: How Oxygen Shortage Affects the Linkage between Innate and Adaptive Immunity

    Directory of Open Access Journals (Sweden)

    Sandra Winning

    2016-01-01

    Full Text Available Dendritic cells (DCs are considered as one of the main regulators of immune responses. They collect antigens, process them, and present typical antigenic structures to lymphocytes, thereby inducing an adaptive immune response. All these processes take place under conditions of oxygen shortage (hypoxia which is often not considered in experimental settings. This review highlights how deeply hypoxia modulates human as well as mouse immature and mature dendritic cell functions. It tries to link in vitro results to actual in vivo studies and outlines how hypoxia-mediated shaping of dendritic cells affects the activation of (innate immunity.

  20. In vitro effects of trichothecenes on human dendritic cells.

    Science.gov (United States)

    Hymery, N; Sibiril, Y; Parent-Massin, D

    2006-09-01

    The aim of this work was to study the in vitro effects of trichothecenes on human dendritic cells. Trichothecenes are mycotoxins produced by fungi such as Fusarium, Myrothecium, and Stachybotrys. Two aspects have been explored in this work: the cytotoxicity of trichothecenes on immature dendritic cells to determine IC 50 (inhibition concentration), and the effects of trichothecenes on dendritic cell maturation process. Two mycotoxins (T-2 and DON) known to be immunotoxic have been tested on a model of monocyte-derived dendritic cells culture. Cytotoxic effects of T-2 toxin and DON on immature dendritic cells showed that DON is less potent than T-2 toxin. The exposure to trichothecenes during dendritic cell maturation upon addition of LPS or TNF-alpha markedly inhibited the up-regulation of maturation markers such as CD-86, HLA-DR and CCR7. Features of LPS or TNF-alpha -mediated maturation of dendritic cells, such as IL-10 and IL-12 secretions and endocytosis, were also impaired in response to trichothecenes treatment. These results suggest trichothecenes have adverse effects on dendritic cells and dendritic cell maturation process.

  1. Tolerogenic dendritic cells for regulatory T cell induction in man

    Directory of Open Access Journals (Sweden)

    Verena eRaker

    2015-11-01

    Full Text Available Dendritic cells are (DC highly specialized professional antigen-presenting cells (APC that regulate immune responses, maintaining the balance between tolerance and immunity. Mechanisms via which they can promote central and peripheral tolerance include clonal deletion, inhibition of memory T cell responses, T cell anergy and induction of regulatory T cells. These properties have led to the analysis of human tolerogenic DC as a therapeutic strategy for induction or re-establishment of tolerance. In the recent years, numerous protocols for the generation of human tolerogenic DC have been developed and their tolerogenic mechanisms, including induction of regulatory T cells, are relatively well understood. Phase I trials have been conducted in autoimmune disease, with results that emphasize the feasibility and safety of treatments with tolerogenic DC. Therefore, the scientific rationale for the use of tolerogenic DC therapy in the fields of transplantation medicine and allergic and autoimmune diseases is strong. This review will give an overview on efforts and protocols to generate human tolerogenic DC with focus on IL-10-modulated DC as inducers of regulatory T cells and discuss their clinical applications and challenges faced in further developing this form of immunotherapy.

  2. Modulation of dendritic cell function by Trichomonas vaginalis-derived secretory products.

    Science.gov (United States)

    Song, Min-Ji; Lee, Jong-Joo; Nam, Young Hee; Kim, Tae-Gyun; Chung, Youn Wook; Kim, Mikyoung; Choi, Ye-Eun; Shin, Myeong Heon; Kim, Hyoung-Pyo

    2015-02-01

    Trichomoniasis caused by the parasitic protozoan Trichomonas vaginalis is the most common sexually transmitted disease in the world. Dendritic cells are antigen presenting cells that initiate immune responses by directing the activation and differentiation of naïve T cells. In this study, we analyzed the effect of Trichomonas vaginalis-derived Secretory Products on the differentiation and function of dendritic cells. Differentiation of bone marrow-derived dendritic cells in the presence of T. vaginalis-derived Secretory Products resulted in inhibition of lipopolysaccharide-induced maturation of dendritic cells, down-regulation of IL-12, and up-regulation of IL-10. The protein components of T. vaginalis-derived Secretory Products were shown to be responsible for altered function of bone marrow- derived dendritic cells. Chromatin immunoprecipitation assay demonstrated that IL-12 expression was regulated at the chromatin level in T. vaginalis-derived Secretory Productstreated dendritic cells. Our results demonstrated that T. vaginalis- derived Secretory Products modulate the maturation and cytokine production of dendritic cells leading to immune tolerance.

  3. High Production of IL-18 by Dendritic Cells Induced by Sera from Patients with Primary Antibody Deficiency

    Directory of Open Access Journals (Sweden)

    Maryam Nourizadeh

    2007-06-01

    Full Text Available Predominantly antibody deficiencies are a category of primary immunodeficiency diseases, whichconsist of several rare disorders such as common variable immunodeficiency (CVID and X-linked agammaglobulinemia (XLA. We evaluated the effects of CVID and XLA patients’ sera as a source of microenviromental factors on maturation and function of monocyte-derived DCs.Blood was collected from 10 CVID and 5 XLA patients before immunoglobulin replacementtherapy and also from 8 healthy volunteers in order to obtain necessary sera for this study. Monocyte derived DCs were generated from blood cells obtained from healthy volunteers in the presence of GM-CSF, IL-4 and 10% serum concentrations from cases and controls. Immature DCs were incubated with monocyte conditioned medium (MCM and TNF-α in order to generate mature DCs. Interleukin 18 (IL-18 production by CD40L-activated mature DCs was measured after 24 hours of culture in vitro.IL-18 production by DCs generated in the presence of CVID and XLA patients’ sera were6.75±2.59 and 7.08±1.75 ng/ml, respectively, which were significantly higher than normal serumconditioned DCs (3.55±0.68 ng/ml.These results suggest that the sera of patients with predominantly antibody deficiencies maycontain soluble factor(s that can induce a significant increase in IL-18 production by DCs.

  4. Cold-induced exodus of postsynaptic proteins from dendritic spines.

    Science.gov (United States)

    Cheng, Hui-Hsuan; Huang, Zu-Han; Lin, Wei-Hsiang; Chow, Wei-Yuan; Chang, Yen-Chung

    2009-02-01

    Dendritic spines are small protrusions on neuronal dendrites and the major target of the excitatory inputs in mammalian brains. Cultured neurons and brain slices are important tools in studying the biochemical and cellular properties of dendritic spines. During the processes of immunocytochemical studies of neurons and the preparation of brain slices, neurons were often kept at temperatures lower than 37 degrees C for varied lengths of time. This study sought to investigate whether and how cold treatment would affect the protein composition of dendritic spines. The results indicated that upon cold treatment four postsynaptic proteins, namely, alpha,beta-tubulins, calcium, calmodulin-dependent protein kinase IIalpha, and cytoplasmic dynein heavy chain and microtubule-associated protein 2, but not PSD-95 or AMPA receptors, exited from the majority of dendritic spines of cultured rat hippocampal neurons in a Gd(3+)-sensitive manner. The cold-induced exit of tubulins from dendritic spines was further found to be an energy-dependent process involving the activation of Gd(3+)-sensitive calcium channels and ryanodine receptors. The results thus indicate that changes in temperature, calcium concentration, and energy supply of the medium surrounding neurons would affect the protein composition of the dendritic spines and conceivably the protein composition of the subcellular organizations, such as the postsynaptic density, in the cytoplasm of dendritic spines.

  5. Calcitriol analog ZK191784 ameliorates acute and chronic dextran sodium sulfate-induced colitis by modulation of intestinal dendritic cell numbers and phenotype

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To investigate the effects of ZK1916784, a low calcemic analog of calcitriol on intestinal inflammation.METHODS: Acute and chronic colitis was induced by dextran sodium sulfate (DSS) according to standard procedures. Mice were treated intraperitoneally with ZK1916784 or placebo and colonic inflammation was evaluated. Cytokine production by mesenterial lymph node (MLN) cells was measured by ELISA.Immunohistochemistry was performed to detect intestinal dendritic cells (DCs) within the colonic tissue,and the effect of the calcitriol analog on DCs was investigated.RESULTS: Treatment with ZK191784 resulted in significant amelioration of disease with a reduced histological score in acute and chronic intestinal inflammation. In animals with acute DSS colitis, down-regulation of colonic inflammation was associated with a dramatic reduction in the secretion of the proinflammatory cytokine interferon (IFN)-γ and a significant increase in intereleukin (IL)-10 by MLN cells.Similarly, in chronic colitis, IL-10 expression in colonic tissue increased 1.4-fold when mice were treated with ZK191784, whereas expression of the Th1-specific transcription factor T-beta decreased by 81.6%. Lower numbers of infiltrating activated CD11c+ DCs were found in the colon in ZK191784-treated mice with acute DSS colitis, and secretion of proinflammatory cytokines by primary mucosal DCs was inhibited in the presence of the calcitriol analog.CONCLUSION: The calcitriol analog ZK191784 demonstrated significant anti-inflammatory properties in experimental colitis that were at least partially mediated by the immunosuppressive effects of the derivate on mucosal DCs.

  6. Plasmacytoid Dendritic Cells Producing Interferon-α (IFN-α) and Inducing Mx1 Play an Important Role for CD4(+) Cells and CD8(+) Cells in Necrotizing Lymphadenitis.

    Science.gov (United States)

    Sato, Hiroko; Asano, Shigeyuki; Mori, Kikuo; Yamazaki, Kazuki; Wakasa, Haruki

    2015-01-01

    We confirmed the characteristic clinical features of necrotizing lymphadenitis (NEL) in 66 cases (23 male, 43 female) in Japan, which included high fever (38-40°), painful cervical lymphadenopathy (62/66, 93.9%), and leukopenia (under 4,000/mm(3)) (25/53, 47.2%), without seasonal occurrence, in a clinicopathological, immunohistochemical, electron microscopic serological study. Patient age varied from 3-55 years, and 72.7% (44/66) of patients were younger than 30 years. Histopathology of NEL was characterized by the presence of CD8(+) immunoblasts, CD123(+) cells (plasmacytoid dendritic cells; PDCs), histiocytes and macrophages phagocytizing CD4(+) apoptotic lymphocytes, but no granulocytes or bacteria. The number of PDCs and CD8(+) cells in lesions tended to increase with time, and PDCs tended to be larger and irregular in the lesions compared with the non-lesion tissue of the lymph nodes. In addition, PDCs showed no temporal morphological change in the lymph nodes. The number of CD4(+) cells in the lymph node lesions sharply decreased from the 2nd to the 4th week, and then tended to increase; however, CD4(+) cells gradually decreased with time in non-lesion tissue. PDCs may produce interferon-α (IFN-α), which induces Mx1 expression. Strong Mx1 immunoreactivity is indicative of IFN-α production. IFN-α induces transformation of CD8(+) cells into immunoblasts, as well as phagocytosis of apoptotic cells derived from CD4(+) cells by macrophages. Thus, PDCs may play an important role with immune cells, including CD8(+) and CD4(+) cells, in necrotizing lymphadenitis.

  7. Sphingosine-1-phosphate receptor inhibition prevents denervation-induced dendritic atrophy.

    Science.gov (United States)

    Willems, Laurent M; Zahn, Nadine; Ferreirós, Nerea; Scholich, Klaus; Maggio, Nicola; Deller, Thomas; Vlachos, Andreas

    2016-03-31

    A hallmark of several major neurological diseases is neuronal cell death. In addition to this primary pathology, secondary injury is seen in connected brain regions in which neurons not directly affected by the disease are denervated. These transneuronal effects on the network contribute considerably to the clinical symptoms. Since denervated neurons are viable, they are attractive targets for intervention. Therefore, we studied the role of Sphingosine-1-phosphate (S1P)-receptor signaling, the target of Fingolimod (FTY720), in denervation-induced dendritic atrophy. The entorhinal denervation in vitro model was used to assess dendritic changes of denervated mouse dentate granule cells. Live-cell microscopy of GFP-expressing granule cells in organotypic entorhino-hippocampal slice cultures was employed to follow individual dendritic segments for up to 6 weeks after deafferentation. A set of slice cultures was treated with FTY720 or the S1P-receptor (S1PR) antagonist VPC23019. Lesion-induced changes in S1P (mass spectrometry) and S1PR-mRNA levels (laser microdissection and qPCR) were determined. Denervation caused profound changes in dendritic stability. Dendritic elongation and retraction events were markedly increased, resulting in a net reduction of total dendritic length (TDL) during the first 2 weeks after denervation, followed by a gradual recovery in TDL. These changes were accompanied by an increase in S1P and S1PR1- and S1PR3-mRNA levels, and were not observed in slice cultures treated with FTY720 or VPC23019. We conclude that inhibition of S1PR signaling prevents dendritic destabilization and denervation-induced dendrite loss. These results suggest a novel neuroprotective effect for pharmaceuticals targeting neural S1PR pathways.

  8. Immune Monitoring Using mRNA-Transfected Dendritic Cells

    DEFF Research Database (Denmark)

    Borch, Troels Holz; Svane, Inge Marie; Met, Özcan

    2016-01-01

    Dendritic cells are known to be the most potent antigen presenting cell in the immune system and are used as cellular adjuvants in therapeutic anticancer vaccines using various tumor-associated antigens or their derivatives. One way of loading antigen into the dendritic cells is by m......RNA electroporation, ensuring presentation of antigen through major histocompatibility complex I and potentially activating T cells, enabling them to kill the tumor cells. Despite extensive research in the field, only one dendritic cell-based vaccine has been approved. There is therefore a great need to elucidate...... and understand the immunological impact of dendritic cell vaccination in order to improve clinical benefit. In this chapter, we describe a method for performing immune monitoring using peripheral blood mononuclear cells and autologous dendritic cells transfected with tumor-associated antigen-encoding mRNA....

  9. Dendritic planarity of Purkinje cells is independent of Reelin signaling.

    Science.gov (United States)

    Kim, Jinkyung; Park, Tae-Ju; Kwon, Namseop; Lee, Dongmyeong; Kim, Seunghwan; Kohmura, Yoshiki; Ishikawa, Tetsuya; Kim, Kyong-Tai; Curran, Tom; Je, Jung Ho

    2015-07-01

    The dendritic planarity of Purkinje cells is critical for cerebellar circuit formation. In the absence of Crk and CrkL, the Reelin pathway does not function resulting in partial Purkinje cell migration and defective dendritogenesis. However, the relationships among Purkinje cell migration, dendritic development and Reelin signaling have not been clearly delineated. Here, we use synchrotron X-ray microscopy to obtain 3-D images of Golgi-stained Purkinje cell dendrites. Purkinje cells that failed to migrate completely exhibited conical dendrites with abnormal 3-D arborization and reduced dendritic complexity. Furthermore, their spines were fewer in number with a distorted morphology. In contrast, Purkinje cells that migrated successfully displayed planar dendritic and spine morphologies similar to normal cells, despite reduced dendritic complexity. These results indicate that, during cerebellar formation, Purkinje cells migrate into an environment that supports development of dendritic planarity and spine formation. While Reelin signaling is important for the migration process, it does not make a direct major contribution to dendrite formation.

  10. The Comparison of Biologic Characteristics between Mice Embryonic Stem Cells and Bone Marrow Derived Dendritic Cells

    Institute of Scientific and Technical Information of China (English)

    Junfeng Liu; Zhixu He; Dong Shen; Jin Huang; Haowen Wang

    2009-01-01

    OBJECTIVE This research was to induce dendritic cells (DCs)from mice embryonic stem cells and bone marrow mononuclear cells in vitro, and then compare the biologic characteristics of them.METHODS Embryonic stem cells (ESCs) suspending cultured in petri dishes were induced to generate embryonic bodies (EBs).Fourteen-day well-developed EBs were transferred to histological culture with the same medium and supplemented 25 ng/ml GM-CSF and 25 ng/ml IL-3. In the next 2 weeks, there were numerous immature DCs outgrown. Meantime, mononuclear cells isolated from mice bone marrow were induced to derive dendritic cells by supplementing 25 ng/ml GM-CSF and 25 ng/ml IL-4, and then the morphology, phenotype and function of both dendritic cells from different origins were examined.RESULTS Growing mature through exposure to lipopolysaccharide (LPS), both ESC-DCs and BM-DCs exhibited dramatic veils of cytoplasm and extensive dendrites on their surfaces, highly expressed CD11c, MHC-Ⅱ and CD86 with strong capacity to stimulate primary T cell responses in mixed leukocyte reaction (MLR).CONCLUSION ESC-DC has the same biologic characteristics as BM-DC, and it provides a new, reliable source for the functional research of DC and next produce corresponding anti-tumor vaccine.

  11. Harnessing Dendritic Cells for Tumor Antigen Presentation

    Energy Technology Data Exchange (ETDEWEB)

    Nierkens, Stefan [Department of Tumor Immunology, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, Geert Grooteplein 28, Nijmegen 6525 GA (Netherlands); Janssen, Edith M., E-mail: edith.janssen@cchmc.org [Division of Molecular Immunology, Cincinnati Children' s Hospital Research Foundation, University of Cincinnati College of Medicine, 3333 Burnet Avenue, Cincinnati, OH 45229 (United States)

    2011-04-26

    Dendritic cells (DC) are professional antigen presenting cells that are crucial for the induction of anti-tumor T cell responses. As a consequence, research has focused on the harnessing of DCs for therapeutic interventions. Although current strategies employing ex vivo-generated and tumor-antigen loaded DCs have been proven feasible, there are still many obstacles to overcome in order to improve clinical trial successes and offset the cost and complexity of customized cell therapy. This review focuses on one of these obstacles and a pivotal step for the priming of tumor-specific CD8{sup +} and CD4{sup +} T cells; the in vitro loading of DCs with tumor antigens.

  12. Induction and identification of rabbit peripheral blood derived dendritic cells

    Science.gov (United States)

    Zhou, Jing; Yang, FuYuan; Chen, WenLi

    2012-03-01

    Purpose: To study a method of the induction of dendritic cells (DCs) from rabbit peripheral blood. Methods: Peripheral blood cells were removed from rabbit, filtered through nylon mesh. Peripheral blood mononuclear cells (PBMC) were isolated from the blood cells by Ficoll-Hypaque centrifugation (density of 1.077g/cm3).To obtain DCs, PBMC were cultured in RPMI1640 medium containing 10% fetal calf serum, 50U/mL penicillin and streptomycin, referred to subsequently as complete medium, at 37°C in 5% CO2 atmosphere for 4 hours. Nonadherent cells were aspirated, adherent cells were continued incubated in complete medium, supplemented with granulocyte/macrophage colony-stimulating factor (GM-CSF, 50ng/ml),and interleukin 4 (IL-4, 50ng/ml) for 9 days. Fluorescein labeled antibodies(anti-CD14, anti-HLA-DR, anti-CD86) were used to sign cells cultured for 3,6,9 days respectively, Then flow cytometry was performed. Results: Ratio of anti-HLA-DR and anti-CD86 labeled cells increased with induction time extension, in contrast with anti-CD14. Conclusion: Dendritic cells can be effectively induced by the method of this experiment, cell maturation status increased with induction time extension.

  13. Homophilic Protocadherin Cell-Cell Interactions Promote Dendrite Complexity

    Directory of Open Access Journals (Sweden)

    Michael J. Molumby

    2016-05-01

    Full Text Available Growth of a properly complex dendrite arbor is a key step in neuronal differentiation and a prerequisite for neural circuit formation. Diverse cell surface molecules, such as the clustered protocadherins (Pcdhs, have long been proposed to regulate circuit formation through specific cell-cell interactions. Here, using transgenic and conditional knockout mice to manipulate γ-Pcdh repertoire in the cerebral cortex, we show that the complexity of a neuron’s dendritic arbor is determined by homophilic interactions with other cells. Neurons expressing only one of the 22 γ-Pcdhs can exhibit either exuberant or minimal dendrite complexity, depending only on whether surrounding cells express the same isoform. Furthermore, loss of astrocytic γ-Pcdhs, or disruption of astrocyte-neuron homophilic matching, reduces dendrite complexity cell non-autonomously. Our data indicate that γ-Pcdhs act locally to promote dendrite arborization via homophilic matching, and they confirm that connectivity in vivo depends on molecular interactions between neurons and between neurons and astrocytes.

  14. Methamphetamine Enhances HIV-1 Infectivity in Monocyte Derived Dendritic Cells

    OpenAIRE

    2008-01-01

    The US is currently experiencing an epidemic of methamphetamine (Meth) use as a recreational drug. Recent studies also show a high prevalence of HIV-1 infection among Meth users. We report that Meth enhances HIV-1 infectivity of dendritic cells as measured by multinuclear activation of a galactosidase indicator (MAGI) cell assay, p24 assay, and LTR-RU5 amplification. Meth induces increased HIV-1 infection in association with an increase in the HIV-1 coreceptors, CXCR4 and CCR5, and infection ...

  15. Differentiation of apical and basal dendrites in pyramidal cells and granule cells in dissociated hippocampal cultures.

    Directory of Open Access Journals (Sweden)

    You Kure Wu

    Full Text Available Hippocampal pyramidal cells and dentate granule cells develop morphologically distinct dendritic arbors, yet also share some common features. Both cell types form a long apical dendrite which extends from the apex of the cell soma, while short basal dendrites are developed only in pyramidal cells. Using quantitative morphometric analyses of mouse hippocampal cultures, we evaluated the differences in dendritic arborization patterns between pyramidal and granule cells. Furthermore, we observed and described the final apical dendrite determination during dendritic polarization by time-lapse imaging. Pyramidal and granule cells in culture exhibited similar dendritic patterns with a single principal dendrite and several minor dendrites so that the cell types were not readily distinguished by appearance. While basal dendrites in granule cells are normally degraded by adulthood in vivo, cultured granule cells retained their minor dendrites. Asymmetric growth of a single principal dendrite harboring the Golgi was observed in both cell types soon after the onset of dendritic growth. Time-lapse imaging revealed that up until the second week in culture, final principal dendrite designation was not stabilized, but was frequently replaced by other minor dendrites. Before dendritic polarity was stabilized, the Golgi moved dynamically within the soma and was repeatedly repositioned at newly emerging principal dendrites. Our results suggest that polarized growth of the apical dendrite is regulated by cell intrinsic programs, while regression of basal dendrites requires cue(s from the extracellular environment in the dentate gyrus. The apical dendrite designation is determined from among multiple growing dendrites of young developing neurons.

  16. Viruses, dendritic cells and the lung

    Directory of Open Access Journals (Sweden)

    Graham Barney S

    2001-06-01

    Full Text Available Abstract The interaction between viruses and dendritic cells (DCs is varied and complex. DCs are key elements in the development of a host response to pathogens such as viruses, but viruses have developed survival tactics to either evade or diminish the immune system that functions to kill and eliminate these micro-organisms. In the present review we summarize current concepts regarding the function of DCs in the immune system, our understanding of how viruses alter DC function to attenuate both the virus-specific and global immune response, and how we may be able to exploit DC function to prevent or treat viral infections.

  17. Metamaterial absorber with random dendritic cells

    Science.gov (United States)

    Zhu, Weiren; Zhao, Xiaopeng

    2010-05-01

    The metamaterial absorber composed of random dendritic cells has been investigated at microwave frequencies. It is found that the absorptivities come to be weaker and the resonant frequency get red shift as the disordered states increasing, however, the random metamaterial absorber still presents high absorptivity more than 95%. The disordered structures can help understanding of the metamaterial absorber and may be employed for practical design of infrared metamaterial absorber, which may play important roles in collection of radiative heat energy and directional transfer enhancement.

  18. Altered MARCH1 ubiquination-regulated dendritic cell immune functions during the early stage of zymosan-induced multiple organ dysfunction syndrome (MODS) in mice.

    Science.gov (United States)

    Li, Fei; Lu, Jiang-yang; Liu, Qian; Wang, Hong-wei; Guo, Huiqin

    2013-02-01

    Using a zymosan-induced mouse model of multiple organ dysfunction syndrome (MODS), we previously found profound increases in spleen immune cells' expressions of ubiquitin and MHC-II molecules and increased CD11c+ dendritic cells (DCs) within 24h of zymosan injection. We postulated that the early stage of MODS altered DCs function via an ubiquitination-associated mechanism. We intraperitoneally injected zymosan into 100 male C57BL/6 mice (0.8mg/g) and randomly divided them into 5 groups based on the days after injection (20mice/group): 1d, 3d, 5d, 7d, and 10d. Mice were examined for spleen CD11c+ DC functions at the indicated days. Untreated mice were used for normal spleen tissue and T cell samples. By qPCR, IL-12 and TNF-α mRNA expressions in spleen CD11c+ DCs were significantly increased in MODS 1d mice; on subsequent days post-injection, these mRNA levels gradually returned to control levels. The same patterns were found for MODS mice DCs induction of untreated mouse T cells proliferation and IL-2 and IFN-γ mRNA expressions. When T cell functions were examined using MODS 1d DCs with and without MG132 treatment, an inhibitor of ubiquitinated protein degradation, T cell functional activities were enhanced by DCs treated with MG132. MODS 1d DCs also had significantly reduced MARCH1 mRNA expression, a key ubiquitin ligase that regulates DCs MHC-II expression. Silencing DCs MARCH1 expression with siRNA resulted in enhancing their induction of T cell functional activities. Using co-immunoprecipitation, Western blot, and flow cytometry assays, we deduced that MARCH1 ubiquitinated DC surface MHC-II molecules to regulate DC's immune functions in MODS mice. Our results suggest that aberrant degradation of spleen DCs MARCH1-mediated ubiquitinated proteins is involved during the earliest stage of MODS development. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Recognition of enteroinvasive Escherichia coli and Shigella flexneri by dendritic cells: distinct dendritic cell activation states

    Directory of Open Access Journals (Sweden)

    Ana Carolina Ramos Moreno

    2012-02-01

    Full Text Available The innate and adaptive immune responses of dendritic cells (DCs to enteroinvasive Escherichia coli (EIEC infection were compared with DC responses to Shigella flexneri infection. EIEC triggered DCs to produce interleukin (IL-10, IL-12 and tumour necrosis factor (TNF-α, whereas S. flexneri induced only the production of TNF-α. Unlike S. flexneri, EIEC strongly increased the expression of toll like receptor (TLR-4 and TLR-5 in DCs and diminished the expression of co-stimulatory molecules that may cooperate to inhibit CD4+ T-lymphocyte proliferation. The inflammation elicited by EIEC seems to be related to innate immunity both because of the aforementioned results and because only EIEC were able to stimulate DC transmigration across polarised Caco-2 cell monolayers, a mechanism likely to be associated with the secretion of CC chemokine ligands (CCL20 and TNF-α. Understanding intestinal DC biology is critical to unravelling the infection strategies of EIEC and may aid in the design of treatments for infectious diseases.

  20. Attenuation of niacin-induced prostaglandin D2 generation by omega-3 fatty acids in THP-1 macrophages and Langerhans dendritic cells

    Directory of Open Access Journals (Sweden)

    VanHorn J

    2012-03-01

    Full Text Available Justin VanHorn1, Jeffrey D Altenburg1, Kevin A Harvey1, Zhidong Xu1, Richard J Kovacs2, Rafat A Siddiqui1,31Cellular Biochemistry Laboratory, Methodist Research Institute, Indianapolis, 2Krannert Institute of Cardiology, Indianapolis, 3Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USAAbstract: Niacin, also known as nicotinic acid, is an organic compound that has several cardio-beneficial effects. However, its use is limited due to the induction of a variable flushing response in most individuals. Flushing occurs from a niacin receptor mediated generation of prostaglandins from arachidonic acid metabolism. This study examined the ability of docosahexaenoic acid, eicosapentaenoic acid, and omega-3 polyunsaturated fatty acids (PUFAs, to attenuate niacin-induced prostaglandins in THP-1 macrophages. Niacin induced both PGD2 and PGE2 generation in a dose-dependent manner. Niacin also caused an increase in cytosolic calcium and activation of cytosolic phospholipase A2. The increase in PGD2 and PGE2 was reduced by both docosahexaenoic acid and eicosapentaenoic acid, but not by oleic acid. Omega-3 PUFAs efficiently incorporated into cellular phospholipids at the expense of arachidonic acid, whereas oleic acid incorporated to a higher extent but had no effect on arachidonic acid levels. Omega-3 PUFAs also reduced surface expression of GPR109A, a human niacin receptor. Furthermore, omega-3 PUFAs also inhibited the niacin-induced increase in cytosolic calcium. Niacin and/or omega-3 PUFAs minimally affected cyclooxygenase-1 activity and had no effect on cyclooxygenase -2 activity. The effects of niacin on PGD2 generation were further confirmed using Langerhans dendritic cells. Results of the present study indicate that omega-3 PUFAs reduced niacin-induced prostaglandins formation by diminishing the availability of their substrate, as well as reducing the surface expression of niacin receptors. In conclusion, this study

  1. Kluyveromyces marxianus and Saccharomyces boulardii induce distinct levels of dendritic cell cytokine secretion and significantly different T cell responses In Vitro

    DEFF Research Database (Denmark)

    Smith, Ida Mosbech; Baker, Adam; Christensen, Jeffrey E;

    2016-01-01

    Interactions between members of the intestinal microbiota and the mucosal immune system can significantly impact human health, and in this context, fungi and food-related yeasts are known to influence intestinal inflammation through direct interactions with specialized immune cells in vivo. The aim...... of the present study was to characterize the immune modulating properties of the food-related yeast Kluyveromyces marxianus in terms of adaptive immune responses indicating inflammation versus tolerance and to explore the mechanisms behind the observed responses. Benchmarking against a Saccharomyces boulardii...... strain with probiotic effects documented in clinical trials, we evaluated the ability of K. marxianus to modulate human dendritic cell (DC) function in vitro. Further, we assessed yeast induced DC modulation of naive T cells toward effector responses dominated by secretion of IFNγ and IL-17 versus...

  2. SK2 channel modulation contributes to compartment-specific dendritic plasticity in cerebellar Purkinje cells.

    Science.gov (United States)

    Ohtsuki, Gen; Piochon, Claire; Adelman, John P; Hansel, Christian

    2012-07-12

    Small-conductance Ca(2+)-activated K(+) channels (SK channels) modulate excitability and curtail excitatory postsynaptic potentials (EPSPs) in neuronal dendrites. Here, we demonstrate long-lasting plasticity of intrinsic excitability (IE) in dendrites that results from changes in the gain of this regulatory mechanism. Using dendritic patch-clamp recordings from rat cerebellar Purkinje cells, we find that somatic depolarization or parallel fiber (PF) burst stimulation induce long-term amplification of synaptic responses to climbing fiber (CF) or PF stimulation and enhance the amplitude of passively propagated sodium spikes. Dendritic plasticity is mimicked and occluded by the SK channel blocker apamin and is absent in Purkinje cells from SK2 null mice. Triple-patch recordings from two dendritic sites and the soma and confocal calcium imaging studies show that local stimulation limits dendritic plasticity to the activated compartment of the dendrite. This plasticity mechanism allows Purkinje cells to adjust the SK2-mediated control of dendritic excitability in an activity-dependent manner.

  3. Inhibitory effects of human immunodeficiency virus gp120 and Tat on CpG-A-induced inflammatory cytokines in plasmacytoid dendritic cells

    Institute of Scientific and Technical Information of China (English)

    Meixin Fang; Ning Xu; Xueting Shao; Jin Yang; Nanping Wu; Hangping Yao

    2012-01-01

    Plasmacytoid dendritic cells (pDCs),not only inhibit viral replication,but also play an essential role in linking the innate and adaptive immune system.In this study,we explored the effects of human immunodeficiency virus (HIV) gp120 and tat on CpG-A-induced inflammatory cytokines in pDCs.The results provided fundamental insights into HIV pathogenesis that may hold promise for preventative and even curative strategies,pDCs were isolated using blood DC antigen 4 (BDCA-4) DC isolation kit,and the purity was analyzed using BDCA-2 antibody by flow cytometry,pDCs and peripheral blood mononuclear cells (PBMCs) were stimulated by either CpG-A (5 μg/ml),gp120 (0.5 μg/ml),tat (0.5 μg/ml),or CpG-A treatment combined with gpl20 or tat.The production of type Ⅰ interferons (IFNs) and other inflammatory cytokines,including tumor necrosis factor-alpha (TNF-α),interlukine-6 (IL-6),and interferon-gammainducible protein-10 (IP-10) in the culture supernatant,was determined by enzyme-linked immunosorbent assay.The results showed that CpG-A induced high levels of type I IFNs and other inflammatory cytokines,including TNF-α,IL-6,and IP-10,in pDCs.Concomitant treatment with gp120 reduced the levels of IFN-α,IFN-β,TNF-α,IL-6,and IP-10 induced by CpG-A in pDCs by 79%,53%,60%,50%,and 34%,respectively,while tat suppressed them by 88%,66%,71%,64%,and 53%,respectively.Similar results were demonstrated in CpGA-treated PBMCs.In conclusion,gp120 and tat are effective inhibitors of the CpG-A-mediated induction of type I IFNs and other inflammatory cytokines from pDCs and PBMCs.

  4. In vivo evidence for dendritic cell lysis by NK cells

    OpenAIRE

    Ferlazzo, Guido

    2012-01-01

    By using an experimental model of anticancer vaccination, we have recently lent support to the assumption, so far only sustained by in vitro data, that natural killer cells can restrain less immunogenic, allegedly tolerogenic, dendritic cells (DCs). This in vivo selection of immunogenic DCs appears to depend on perforin and to be associated with a more protective tumor-specific T lymphocyte response.

  5. Dendritic cell-tumor cell hybrids and immunotherapy

    DEFF Research Database (Denmark)

    Cathelin, Dominique; Nicolas, Alexandra; Bouchot, André

    2011-01-01

    Dendritic cells (DC) are professional antigen-presenting cells currently being used as a cellular adjuvant in cancer immunotherapy strategies. Unfortunately, DC-based vaccines have not demonstrated spectacular clinical results. DC loading with tumor antigens and DC differentiation and activation...

  6. Cigarette smoke differentially modulates dendritic cell maturation and function in time

    NARCIS (Netherlands)

    Givi, Masoumeh Ezzati; Folkerts, Gert; Wagenaar, Gerry T M; Redegeld, Frank A; Mortaz, Esmaeil

    2015-01-01

    BACKGROUND: Dendritic cells (DCs) as professional antigen presenting cells (APCs) play a critical role in the regulation of host immune responses. DCs evolve from immature, antigen-capturing cells, to mature antigen-presenting cells. The relative contribution of DCs to cigarette smoke-induced inflam

  7. Human plasmacytoid dendritic cells: from molecules to intercellular communication network

    NARCIS (Netherlands)

    Mathan, T.S.M.; Figdor, C.G.; Buschow, S.I.

    2013-01-01

    Plasmacytoid dendritic cells (pDCs) are a specific subset of naturally occurring dendritic cells, that secrete large amounts of Type I interferon and play an important role in the immune response against viral infection. Several studies have highlighted that they are also effective antigen presentin

  8. Unique immunomodulatory effects of azelastine on dendritic cells in vitro.

    Science.gov (United States)

    Schumacher, S; Kietzmann, M; Stark, H; Bäumer, W

    2014-11-01

    Allergic contact dermatitis and atopic dermatitis are among the most common inflammatory skin diseases in western countries, and antigen-presenting cells like dendritic cells (DC) are key players in their pathophysiology. Histamine, an important mediator of allergic reactions, influences DC maturation and cytokine secretion, which led us to investigate the immunomodulatory potential of the well-known histamine H1 receptor antagonists: azelastine, olopatadine, cetirizine, and pyrilamine. Unlike other H1 antihistamines, azelastine decreased lipopolysaccharide-induced tumor necrosis factor α and interleukin-12 secretion from murine bone marrow-derived DC. This effect was independent of histamine receptors H1, H2, or H4 and may be linked to inhibition of the nuclear factor kappa B pathway. Moreover, only azelastine reduced proliferation of allogenic T cells in a mixed leukocyte reaction. We then tested topical application of the H1 antihistamines on mice sensitized against toluene-2,4-diisocyanate, a model of Th2-mediated allergic contact dermatitis. In contrast to the in vitro results, all investigated substances were efficacious in reducing allergic ear swelling. Azelastine has unique effects on dendritic cells and T cell interaction in vitro. However, this did not translate into superior in vivo efficacy for Th2-mediated allergic dermatitis, possibly due to the effects of the antihistamines on other cell types involved in skin inflammation. Future research will have to clarify whether these properties are relevant to in vivo models of allergic inflammation with a different T cell polarization.

  9. Ultrastructure of Purkinje cell perikarya and their dendritic processes in the rat cerebellar cortex in experimental encephalopathy induced by chronic application of valproate.

    Science.gov (United States)

    Sobaniec-Lotowska, M E

    2001-12-01

    Long-term intragastric administration of the antiepileptic drug sodium valproate (Vuprol Polfa) to rats for 1, 3, 6, 9 and 12 months, once daily at the effective dose of 200 mg/kg body weight showed morphological evidence of encephalopathy, manifested by numerous nonspecific changes within Purkinje cell perikarya and their dendritic processes. The first ultrastructural abnormalities appeared after 3 months. They became more severe in animals with longer survival and were most pronounced after 12 months. The changes were maintained both 1 and 3 months after drug withdrawal. Mitochondria of Purkinje cell perikarya were most severely affected. Damage to mitochondria was accompanied by disintegration and fragmentation of granular endoplasmic reticulum, dilation of channels and cisterns of Golgi apparatus, enlargement of smooth endoplasmic reticulum elements including submembranous cisterns, and accumulation of profuse lipofuscin deposits. Frequently, Purkinje cells appeared as dark ischemic neurones, with focally damaged cellular membrane and features of disintegration. Swollen Bergmann's astrocytes were seen among damaged Purkinje cells or at the site of their loss. The general pattern of submicroscopic alterations of Purkinje cell perikarya suggested severe disorders in several intercellular biochemical extents, including inhibition of oxidative phosphorylation and abnormal protein synthesis, both of which could lead to lethal damage. Ultrastructural abnormalities within dendrites were characterized by damage to elements of smooth endoplasmic reticulum, which was considerably enlarged, with formation of large vacuolar structures situated deep in the dendroplasm. Mitochondrial lesions and alterations in cytoskeletal elements--disintegration of microtubules or even their complete loss--were also observed. The general pattern of abnormalities within the organelles and cytoskeletal elements of dendritic processes in Purkinje cells in the VPA chronic experimental model

  10. Type I TARPs promote dendritic growth of early postnatal neocortical pyramidal cells in organotypic cultures.

    Science.gov (United States)

    Hamad, Mohammad I K; Jack, Alexander; Klatt, Oliver; Lorkowski, Markus; Strasdeit, Tobias; Kott, Sabine; Sager, Charlotte; Hollmann, Michael; Wahle, Petra

    2014-04-01

    The ionotropic α-amino-3-hydroxy-5-methyl-4-isoxazole propionate glutamate receptors (AMPARs) have been implicated in the establishment of dendritic architecture. The transmembrane AMPA receptor regulatory proteins (TARPs) regulate AMPAR function and trafficking into synaptic membranes. In the current study, we employ type I and type II TARPs to modulate expression levels and function of endogenous AMPARs and investigate in organotypic cultures (OTCs) of rat occipital cortex whether this influences neuronal differentiation. Our results show that in early development [5-10 days in vitro (DIV)] only the type I TARP γ-8 promotes pyramidal cell dendritic growth by increasing spontaneous calcium amplitude and GluA2/3 expression in soma and dendrites. Later in development (10-15 DIV), the type I TARPs γ-2, γ-3 and γ-8 promote dendritic growth, whereas γ-4 reduced dendritic growth. The type II TARPs failed to alter dendritic morphology. The TARP-induced dendritic growth was restricted to the apical dendrites of pyramidal cells and it did not affect interneurons. Moreover, we studied the effects of short hairpin RNA-induced knockdown of endogenous γ-8 and showed a reduction of dendritic complexity and amplitudes of spontaneous calcium transients. In addition, the cytoplasmic tail (CT) of γ-8 was required for dendritic growth. Single-cell calcium imaging showed that the γ-8 CT domain increases amplitude but not frequency of calcium transients, suggesting a regulatory mechanism involving the γ-8 CT domain in the postsynaptic compartment. Indeed, the effect of γ-8 overexpression was reversed by APV, indicating a contribution of NMDA receptors. Our results suggest that selected type I TARPs influence activity-dependent dendritogenesis of immature pyramidal neurons.

  11. Influence of organophosphate poisoning on human dendritic cells.

    Science.gov (United States)

    Schäfer, Marina; Koppe, Franziska; Stenger, Bernhard; Brochhausen, Christoph; Schmidt, Annette; Steinritz, Dirk; Thiermann, Horst; Kirkpatrick, Charles James; Pohl, Christine

    2013-12-05

    Organophosphourus compounds (OPC, including nerve agents and pesticides) exhibit acute toxicity by inhibition of acetylcholinesterase. Lung affections are frequent complications and a risk factor for death. In addition, epidemiological studies reported immunological alterations after OPC exposure. In our experiments we investigated the effects of organophosphourus pesticides dimethoate and chlorpyrifos on dendritic cells (DC) that are essential for the initial immune response, especially in the pulmonary system. DC, differentiated from the monocyte cell line THP-1 by using various cytokines (IL-4, GM-CSF, TNF-α, Ionomycin), were exposed to organophosphourus compounds at different concentrations for a 24h time period. DC were characterized by flow cytometry and immunofluorescence using typical dendritic cell markers (e.g., CD11c, CD209 and CD83). After OPC exposure we investigated cell death, the secretion profile of inflammatory mediators, changes of DC morphology, and the effect on protein kinase signalling pathways. Our results revealed a successful differentiation of THP-1 into DC. OPC exposure caused a significant concentration-dependent influence on DC: Dendrites of the DC were shortened and damaged, DC-specific cell surface markers (i.e., CD83and CD209) decreased dramatically after chlorpyrifos exposure. Interestingly, the effects caused by dimethoate were in general less pronounced. The organophosphourus compounds affected the release of inflammatory cytokines, such as IL-1ß and IL-8. The anti-inflammatory cytokine IL-10 was significantly down regulated. Protein kinases like the Akt family or ERK, which are essential for cell survival and proliferation, were inhibited by both OPC. These findings indicate that the tested organophosphourus compounds induced significant changes in cell morphology, inhibited anti-inflammatory cytokines and influenced important protein signalling pathways which are involved in regulation of apoptosis. Thus our results highlight

  12. Study on immune function of dendritic cells in patients with esophageal carcinoma

    Institute of Scientific and Technical Information of China (English)

    Shen-Ren Chen; Yi-Ping Luo; Jin-Kun Zhang; Wei Yang; Zhi-Chao Zhen; Lin-Xin Chen; Wei Zhang

    2004-01-01

    AIM: To investigate the immune function of dendritic cells from both peripheral blood and operated tissues of esophageal carcinoma patients in order to find the relationship between the immune function of dendritic cells and the pathogenesis of esophageal carcinoma.METHODS: The expression of CD83, CD80, and CD86 on the surface of dendritic cells cultured from the peripheral blood of patients was detected compared with that from health donors using flow cytometry. The ability of dendritic cells to induce T lymphocyte proliferation was evaluated by a liquid scintillation counter. The expression of CD80, CD86,CD83, and S-100 proteins was assessed in esophageal carcinoma tissues using immunohistochemical method.RESULTS: Compared with those from healthy donors,dendirtic cells cultured from the peripheral blood of patients expressed lower CD80 and CD86. Furthermore, the ability of dendritic cells in patients to induce T lymphocyte proliferation was significantly lower than that of the control group. Compared with the control group, the positive expression ratio and frequencies of CDS0, CD86, and S100 in esophageal carcinoma tissues were significantly down regulated. The expression of CD83 was up-regulated in the pericancerous tissues, but no expression was found in the cancerous nodules,CONCLUSION: The impaired immune function and the decreased number of dendritic cells cause pathogenesis and progression of esophageal carcinoma.

  13. Dendritic cell function in vivo during the steady state: a role in peripheral tolerance.

    Science.gov (United States)

    Steinman, Ralph M; Hawiger, Daniel; Liu, Kang; Bonifaz, Laura; Bonnyay, David; Mahnke, Karsten; Iyoda, Tomonori; Ravetch, Jeffrey; Dhodapkar, Madhav; Inaba, Kayo; Nussenzweig, Michel

    2003-04-01

    The avoidance of autoimmunity requires mechanisms to actively silence or tolerize self reactive T cells in the periphery. During infection, dendritic cells are not only capturing microbial antigens, but also are processing self antigens from dying cells as well as innocuous environmental proteins. Since the dendritic cells are maturing in response to microbial and other stimuli, peptides will be presented from both noxious and innocuous antigens. Therefore it would be valuable to have mechanisms whereby dendritic cells, prior to infection, establish tolerance to those self and environmental antigens that can be processed upon pathogen encounter. In the steady state, prior to acute infection and inflammation, dendritic cells are in an immature state and not fully differentiated to carry out their known roles as inducers of immunity. These immature cells are not inactive, however. They continuously circulate through tissues and into lymphoid organs, capturing self antigens as well as innocuous environmental proteins. Recent experiments have provided direct evidence that antigen-loaded immature dendritic in vivo silence T cells either by deleting them or by expanding regulatory T cells. In this way, it is proposed that the immune system overcomes at least some of the risk of developing autoimmunity and chronic inflammation. It is proposed that dendritic cells play a major role in defining immunologic self, not only centrally in the thymus but also in the periphery.

  14. Information Fusion for Anomaly Detection with the Dendritic Cell Algorithm

    CERN Document Server

    Greensmith, Julie; Tedesco, Gianni

    2010-01-01

    Dendritic cells are antigen presenting cells that provide a vital link between the innate and adaptive immune system, providing the initial detection of pathogenic invaders. Research into this family of cells has revealed that they perform information fusion which directs immune responses. We have derived a Dendritic Cell Algorithm based on the functionality of these cells, by modelling the biological signals and differentiation pathways to build a control mechanism for an artificial immune system. We present algorithmic details in addition to experimental results, when the algorithm was applied to anomaly detection for the detection of port scans. The results show the Dendritic Cell Algorithm is sucessful at detecting port scans.

  15. Toll-like receptor 3-induced immune response by poly(D,L-lactide-co-glycolide nanoparticles for dendritic cell-based cancer immunotherapy

    Directory of Open Access Journals (Sweden)

    Han HD

    2016-11-01

    Full Text Available Hee Dong Han,1,* Yeongseon Byeon,1,* Tae Heung Kang,1 In Duk Jung,1 Jeong-Won Lee,2 Byung Cheol Shin,3 Young Joo Lee,4 Anil K Sood,5–7 Yeong-Min Park1 1Department of Immunology, School of Medicine, Konkuk University, Chungwondaero, Chungju-Si, Chungcheongbuk-Do, 2Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 3Bio/Drug Discovery Division, Korea Research Institute of Chemical Technology, Yuseong-gu, Daejeon, 4Department of Bioscience and Biotechnology, Sejong University, Kwang-Jin-Gu, Seoul, South Korea; 5Department of Gynecologic Oncology and Reproductive Medicine, 6Department of Cancer Biology, 7Center for RNA Interference and Non-coding RNA, The University of Texas MD Anderson Cancer Center, TX, USA *These authors contributed equally to this work Abstract: Dendritic cells (DCs are potent professional antigen-presenting cells that are capable of initiating a primary immune response and activating T cells, and they play a pivotal role in the immune responses of the host to cancer. Prior to antigen presentation, efficient antigen and adjuvant uptake by DCs is necessary to induce their maturation and cytokine generation. Nanoparticles (NPs are capable of intracellular delivery of both antigen and adjuvant to DCs. Here, we developed an advanced poly(D,L-lactide-co-glycolide (PLGA-NP encapsulating both ovalbumin (OVA as a model antigen and polyinosinic-polycytidylic acid sodium salt (Toll-like receptor 3 ligand as an adjuvant to increase intracellular delivery and promote DC maturation. The PLGA-NPs were taken up by DCs, and their uptake greatly facilitated major histocompatibility class I antigen presentation in vitro. Moreover, vaccination with PLGA-NP-treated DCs led to the generation of ovalbumin-specific CD8+ T cells, and the resulting antitumor efficacy was significantly increased in EG.7 and TC-1 tumor-bearing mice compared to control mice (P<0.01. Taken together, these

  16. Genomics and proteomics of immune modulatory effects of a butanol fraction of echinacea purpurea in human dendritic cells

    National Research Council Canada - National Science Library

    Wang, Chien-Yu; Staniforth, Vanisree; Chiao, Ming-Tsang; Hou, Chia-Chung; Wu, Han-Ming; Yeh, Kuo-Chen; Chen, Chun-Houh; Hwang, Pei-Ing; Wen, Tuan-Nan; Shyur, Lie-Fen; Yang, Ning-Sun

    2008-01-01

    Echinacea spp. extracts and the derived phytocompounds have been shown to induce specific immune cell activities and are popularly used as food supplements or nutraceuticals for immuno-modulatory functions. Dendritic cells (DCs...

  17. Dendritic cells in hepatitis C virus infection: key players in the IFNL3-genotype response.

    Science.gov (United States)

    O'Connor, Kate S; George, Jacob; Booth, David; Ahlenstiel, Golo

    2014-12-21

    Recently, single nucleotide polymorphisms, in the vicinity of the interferon lambda 3 (IFNL3) gene have been identified as the strongest predictor of spontaneous and treatment induced clearance of hepatitis C virus (HCV) infection. Since then, increasing evidence has implicated the innate immune response in mediating the IFNL3 genotype effect. Dendritic cells (DCs) are key to the host immune response in HCV infection and their vital role in the IFNL3 genotype effect is emerging. Reports have identified subclasses of DCs, particularly myeloid DC2s and potentially plasmacytoid DCs as the major producers of IFNL3 in the setting of HCV infection. Given the complexities of dendritic cell biology and the conflicting current available data, this review aims to summarize what is currently known regarding the role of dendritic cells in HCV infection and to place it into context of what is know about lambda interferons and dendritic cells in general.

  18. Infection of nonhost species dendritic cells in vitro with an attenuated myxoma virus induces gene expression that predicts its efficacy as a vaccine vector.

    Science.gov (United States)

    Top, S; Foulon, E; Pignolet, B; Deplanche, M; Caubet, C; Tasca, C; Bertagnoli, S; Meyer, G; Foucras, G

    2011-12-01

    Recombinant myxoma virus (MYXV) can be produced without a loss of infectivity, and its highly specific host range makes it an ideal vaccine vector candidate, although careful examination of its interaction with the immune system is necessary. Similar to rabbit bone marrow-derived dendritic cells (BM-DCs), ovine dendritic cells can be infected by SG33, a MYXV vaccine strain, and support recombinant antigen expression. The frequency of infected cells in the nonhost was lower and the virus cycle was abortive in these cell types. Among BM-DC subpopulations, Langerhans cell-like DCs were preferentially infected at low multiplicities of infection. Interestingly, ovine BM-DCs remained susceptible to MYXV after maturation, although apoptosis occurred shortly after infection as a function of the virus titer. When gene expression was assessed in infected BM-DC cultures, type I interferon (IFN)-related and inflammatory genes were strongly upregulated. DC gene expression profiles were compared with the profiles produced by other poxviruses in interaction with DCs, but very few commonalities were found, although genes that were previously shown to predict vaccine efficacy were present. Collectively, these data support the idea that MYXV permits efficient priming of adaptive immune responses and should be considered a promising vaccine vector along with other poxviruses.

  19. Radiation tolerance of boron doped dendritic web silicon solar cells

    Science.gov (United States)

    Rohatgi, A.

    1980-01-01

    The potential of dendritic web silicon for giving radiation hard solar cells is compared with the float zone silicon material. Solar cells with n(+)-p-P(+) structure and approximately 15% (AMl) efficiency were subjected to 1 MeV electron irradiation. Radiation tolerance of web cell efficiency was found to be at least as good as that of the float zone silicon cell. A study of the annealing behavior of radiation-induced defects via deep level transient spectroscopy revealed that E sub v + 0.31 eV defect, attributed to boron-oxygen-vacancy complex, is responsible for the reverse annealing of the irradiated cells in the temperature range of 150 to 350 C.

  20. Triggering of dendritic cell apoptosis by xanthohumol.

    Science.gov (United States)

    Xuan, Nguyen Thi; Shumilina, Ekaterina; Gulbins, Erich; Gu, Shuchen; Götz, Friedrich; Lang, Florian

    2010-07-01

    Xanthohumol, a flavonoid from beer with anticancer activity is known to trigger apoptosis in a variety of tumor cells. Xanthohumol further has anti-inflammatory activity. However, little is known about the effect of xanthohumol on survival and function of immune cells. The present study thus addressed the effect of xanthohumol on dendritic cells (DCs), key players in the regulation of innate and adaptive immunity. To this end, mouse bone marrow-derived DCs were treated with xanthohumol with subsequent assessment of enzymatic activity of acid sphingomyelinase (Asm), ceramide formation determined with anti-ceramide antibodies in FACS and immunohistochemical analysis, caspase activity utilizing FITC conjugated anti-active caspase 8 or caspase 3 antibodies in FACS and by Western blotting, DNA fragmentation by determining the percentage of cells in the sub-G1 phase and cell membrane scrambling by annexin V binding in FACS analysis. As a result, xanthohumol stimulated Asm, enhanced ceramide formation, activated caspases 8 and 3, triggered DNA fragmentation and led to cell membrane scrambling, all effects virtually absent in DCs from gene targeted mice lacking functional Asm or in wild-type cells treated with sphingomyelinase inhibitor amitriptyline. In conclusion, xanthohumol stimulated Asm leading to caspase activation and apoptosis of bone marrow-derived DCs.

  1. Redefining the role of dendritic cells in periodontics.

    Science.gov (United States)

    Venkatesan, Gomathinayagam; Uppoor, Ashita; Naik, Dilip G

    2013-11-01

    A properly functioning adaptive immune system signifies the best features of life. It is diverse beyond compare, tolerant without fail, and capable of behaving appropriately with a myriad of infections and other challenges. Dendritic cells (DCs) are required to explain how this remarkable system is energized and directed. DCs consist of a family of antigen presenting cells, which are bone-marrow-derived cells that patrol all tissues of the body with the possible exceptions of the brain and testes. DCs function to capture bacteria and other pathogens for processing and presentation to T cells in the secondary lymphoid organs. They serve as an essential link between innate and adaptive immune systems and induce both primary and secondary immune responses. As a result of progress worldwide, there is now evidence of a central role for dendritic cells in initiating antigen-specific immunity and tolerance. This review addresses the origins and migration of DCs to target sites, their basic biology and plasticity in playing a key role in periodontal diseases, and finally, selected strategies being pursued to harness its ability to prevent periodontal diseases.

  2. A novel cell subset:Interferon-producing killer dendritic cells

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Recent reports introduce a novel cell subset of DCs with antigenic phenotypes shared by both NK cells and B cells, but without surface markers of pDCs and T cells, appearing to be a chimera of NK cells and DCs, namely interferon-producing killer dendritic cells(IKDCs).IKDCs not only secret type I and type II interferons to recognize and kill tumor cells effectively, but also express MHC-II molecules to present antigens.Thus, IKDCs are considered as important immunosurveilance cells for tumors, providing a link between innate and adaptive immunity.

  3. CD56 marks human dendritic cell subsets with cytotoxic potential

    NARCIS (Netherlands)

    Roothans, D.; Smits, E.; Lion, E.; Tel, J.; Anguille, S.

    2013-01-01

    Human plasmacytoid and myeloid dendritic cells (DCs), when appropriately stimulated, can express the archetypal natural killer (NK)-cell surface marker CD56. In addition to classical DC functions, CD56+ DCs are endowed with an unconventional cytotoxic capacity.

  4. IL-10 and TGF-β Control of Dendritic Cells at Environmental Interfaces

    NARCIS (Netherlands)

    M.J.H. Girard-Madoux (Mathilde)

    2014-01-01

    markdownabstract__Abstract__ Dendritic cells (DC) are necessary to maintain homeostasis and are essential in regulating immune responses. DC induce effector T cell responses to invading pathogens and promote regulatory T cell (Treg) differentiation to harmless antigens. Interleukin-10 (IL-10) and t

  5. Cisplatin induces tolerogenic dendritic cells in response to TLR agonists via the abundant production of IL-10, thereby promoting Th2- and Tr1-biased T-cell immunity

    Science.gov (United States)

    Kim, Hongmin; Kwon, Kee Woong; Im, Sin-Hyeog; Lee, Bo Ryeong; Ha, Sang-Jun; Shin, Sung Jae

    2016-01-01

    Although many advantageous roles of cisplatin (cis-diamminedichloroplatinum (II), CDDP) have been reported in cancer therapy, the immunomodulatory roles of cisplatin in the phenotypic and functional alterations of dendritic cells (DCs) are poorly understood. Here, we investigated the effect of cisplatin on the functionality of DCs and the changes in signaling pathways activated upon toll-like receptor (TLR) stimulation. Cisplatin-treated DCs down-regulated the expression of cell surface molecules (CD80, CD86, MHC class I and II) and up-regulated endocytic capacity in a dose-dependent manner. Upon stimulation with various TLR agonists, cisplatin-treated DCs showed markedly increased IL-10 production through activation of the p38 MAPK and NF-κB signaling pathways without altering the levels of TNF-α and IL-12p70, indicating the cisplatin-mediated induction of tolerogenic DCs. This effect was dependent on the production of IL-10 from DCs, as neither DCs isolated from IL-10−/− mice nor IL-10-neutralized DCs generated tolerogenic DCs. Interestingly, DCs that were co-treated with cisplatin and lipopolysaccharide (LPS) exhibited a decreased immunostimulatory capacity for inducing the proliferation of Th1- and Th17-type T cells; instead, these DCs contributed to Th2-type T cell immunity. Furthermore, in vitro and in vivo investigations revealed a unique T cell population, IL-10-producing CD3+CD4+LAG-3+CD49b+CD25−Foxp3− Tr1 cells, that was significantly increased without altering the Foxp3+ regulatory T cell population. Taken together, our results suggest that cisplatin induces immune-suppressive tolerogenic DCs in TLR agonist-induced inflammatory conditions via abundant IL-10 production, thereby skewing Th cell differentiation towards Th2 and Tr1 cells. This relationship may provide cancer cells with an opportunity to evade the immune system. PMID:27172902

  6. Viral infection increases glucocorticoid-induced interleukin-10 production through ERK-mediated phosphorylation of the glucocorticoid receptor in dendritic cells: potential clinical implications.

    Directory of Open Access Journals (Sweden)

    Sinnie Sin Man Ng

    Full Text Available The hypothalamic-pituitary-adrenal axis plays a central role in the adaptive response to stress including infection of pathogens through glucocorticoids. Physical and/or mental stress alter susceptibility to viral infection possibly by affecting this regulatory system, thus we explored potential cellular targets and mechanisms that underlie this phenomenon in key immune components dendritic cells (DCs. Dexamethasone (DEX treatment and subsequent Newcastle disease virus (NDV infection most significantly and cooperatively stimulated mRNA expression of the interleukin (IL-10 in murine bone marrow-derived DCs among 89 genes involved in the Toll-like receptor signaling pathways. NDV increased DEX-induced IL-10 mRNA and protein expression by 7- and 3-fold, respectively, which was observed from 3 hours after infection. Conventional DCs (cDCs, but not plasmacytoid DCs (pDCs were major sources of IL-10 in bone marrow-derived DCs treated with DEX and/or infected with NDV. Murine cytomegalovirus and DEX increased serum IL-10 cooperatively in female mice. Pre-treatment of DCs with the extracellular signal-regulated kinase (ERK inhibitor U0126 abolished cooperative induction of IL-10 by DEX and NDV. Further, ERK overexpression increased IL-10 promoter activity stimulated by wild-type human GR but not by its mutant defective in serine 203, whereas ERK knockdown abolished NDV/DEX cooperation on IL-10 mRNA and phosphorylation of the mouse GR at serine 213. NDV also increased DEX-induced mRNA expression of three known glucocorticoid-responsive genes unrelated to the Toll-like receptor signaling pathways in DCs. These results indicate that virus and glucocorticoids cooperatively increase production of anti-inflammatory cytokine IL-10 by potentiating the transcriptional activity of GR in DCs, through which virus appears to facilitate its own propagation in infected hosts. The results may further underlie in part known exacerbation of IL-10/T helper-2-related

  7. Melanoma cell-derived exosomes alter macrophage and dendritic cell functions in vitro.

    Science.gov (United States)

    Marton, Annamaria; Vizler, Csaba; Kusz, Erzsebet; Temesfoi, Viktoria; Szathmary, Zsuzsa; Nagy, Krisztina; Szegletes, Zsolt; Varo, Gyorgy; Siklos, Laszlo; Katona, Robert L; Tubak, Vilmos; Howard, O M Zack; Duda, Erno; Minarovits, Janos; Nagy, Katalin; Buzas, Krisztina

    2012-01-01

    To clarify controversies in the literature of the field, we have purified and characterized B16F1 melanoma cell derived exosomes (mcd-exosomes) then we attempted to dissect their immunological activities. We tested how mcd-exosomes influence CD4+ T cell proliferation induced by bone marrow derived dendritic cells; we quantified NF-κB activation in mature macrophages stimulated with mcd-exosomes, and we compared the cytokine profile of LPS-stimulated, IL-4 induced, and mcd-exosome treated macrophages. We observed that mcd-exosomes helped the maturation of dendritic cells, enhancing T cell proliferation induced by the treated dendritic cells. The exosomes also activated macrophages, as measured by NF-κB activation. The cytokine and chemokine profile of macrophages treated with tumor cell derived exosomes showed marked differences from those induced by either LPS or IL-4, and it suggested that exosomes may play a role in the tumor progression and metastasis formation through supporting tumor immune escape mechanisms.

  8. Harnessing dendritic cells in inflammatory skin diseases.

    Science.gov (United States)

    Chu, Chung-Ching; Di Meglio, Paola; Nestle, Frank O

    2011-02-01

    The skin immune system harbors a complex network of dendritic cells (DCs). Recent studies highlight a diverse functional specialization of skin DC subsets. In addition to generating cellular and humoral immunity against pathogens, skin DCs are involved in tolerogenic mechanisms to ensure the maintenance of immune homeostasis, as well as in pathogenesis of chronic inflammation in the skin when excessive immune responses are initiated and unrestrained. Harnessing DCs by directly targeting DC-derived molecules or selectively modulate DC subsets is a convincing strategy to tackle inflammatory skin diseases. In this review we discuss recent advances underlining the functional specialization of skin DCs and discuss the potential implication for future DC-based therapeutic strategies.

  9. Role of Dendritic Cells in Immune Dysfunction

    Science.gov (United States)

    Savary, Cherylyn A.

    1998-01-01

    The specific aims of the project were: (1) Application of the NASA bioreactor to enhance cytokine-regulated proliferation and maturation of dendritic cells (DC). (2) Compare the frequency and function of DC in normal donors and immunocompromised cancer patients. (3) Analyze the effectiveness of cytokine therapy and DC-assisted immunotherapy (using bioreactor-expanded DC) in a murine model of experimental fungal disease. Our investigations have provided new insight into DC immunobiology and have led to the development of methodology to evaluate DC in blood of normal donors and patients. Information gained from these studies has broadened our understanding of possible mechanisms involved in the immune dysfunction of space travelers and earth-bound cancer patients, and could contribute to the design of novel therapies to restore/preserve immunity in these individuals. Several new avenues of investigation were also revealed. The results of studies completed during Round 2 are summarized.

  10. Equine dendritic cells generated with horse serum have enhanced functionality in comparison to dendritic cells generated with fetal bovine serum

    OpenAIRE

    Ziegler, A; Everett, H.; Hamza, E; Garbani, M; Gerber, V.; Marti, E; Steinbach, F

    2016-01-01

    Background: Dendritic cells are professional antigen-presenting cells that play an essential role in the initiation and modulation of T cell responses. They have been studied widely for their potential clinical applications, but for clinical use to be successful, alternatives to xenogeneic substances like fetal bovine serum (FBS) in cell culture need to be found. Protocols for the generation of dendritic cells ex vivo from monocytes are well established for several species, including horses. ...

  11. The impact of extracellular acidosis on dendritic cell function.

    Science.gov (United States)

    Vermeulen, Mónica Elba; Gamberale, Romina; Trevani, Analía Silvina; Martínez, Diego; Ceballos, Ana; Sabatte, Juan; Giordano, Mirta; Geffner, Jorge Raúl

    2004-01-01

    Dendritic cells (DCs) are the most efficient antigen-presenting cells. They are activated in the periphery by conserved pathogen molecules and by inflammatory mediators produced by a variety of cell types in response to danger signals. It is widely appreciated that inflammatory responses in peripheral tissues are usually associated with the development of acidic microenvironments. Surprisingly, there are relatively few studies directed to analyze the effect of extracellular acidosis on the immune response. We focus on the influence of extracellular acidosis on the function of immature DCs. The results presented here show that acidosis activates DCs. It increases the acquisition of extracellular antigens for MHC class I-restricted presentation and the ability of antigen-pulsed DCs to induce both specific CD8+ CTL and B-cell responses. These findings may have important implications to our understanding of the mechanisms through which DCs sense the presence of infection or inflammation in nonlymphoid tissues.

  12. Dendritic Cell-Based Immunotherapy for Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Hanka Jähnisch

    2010-01-01

    Full Text Available Dendritic cells (DCs are professional antigen-presenting cells (APCs, which display an extraordinary capacity to induce, sustain, and regulate T-cell responses providing the opportunity of DC-based cancer vaccination strategies. Thus, clinical trials enrolling prostate cancer patients were conducted, which were based on the administration of DCs loaded with tumor-associated antigens. These clinical trials revealed that DC-based immunotherapeutic strategies represent safe and feasible concepts for the induction of immunological and clinical responses in prostate cancer patients. In this context, the administration of the vaccine sipuleucel-T consisting of autologous peripheral blood mononuclear cells including APCs, which were pre-exposed in vitro to the fusion protein PA2024, resulted in a prolonged overall survival among patients with metastatic castration-resistent prostate cancer. In April 2010, sipuleucel-T was approved by the United States Food and Drug Administration for prostate cancer therapy.

  13. Study on biological characters of SGC7901 gastric cancer cell-dendritic cell fusion vaccines

    Institute of Scientific and Technical Information of China (English)

    Kun Zhang; Peng-Fen Gao; Pei-Wu Yu; Yun Rao; Li-Xin Zhou

    2006-01-01

    AIM: To detect the biological characters of the SGC7901 gastric cancer cell-dendritic cell fusion vaccines.METHODS: The suspending living SGC7901 gastric cancer cells and dendritic cells were induced to be fusioned by polyethylene glycol. Pure fusion cells were obtained by selective culture with the HAT/HT culture systems.The fusion cells were counted at different time points of culture and their growth curves were drawn to reflect their proliferative activities. The fusion cells were also cultured in culture medium to investigate whether they could grow into cell clones. MTT method was used to test the stimulating abilities of the fusion cells on T lymphocytes' proliferations. Moreover, the fusion cells were planted into nude mice to observe whether they could grow into new planted tumors in this kind of immunodeficiency animals.RESULTS: The fusion cells had weaker proliferative activity and clone abilities than their parental cells. When they were cultured, the counts of cells did not increase remarkably, nor could they grow into cell clones in culture medium. The fusion cells could not grow into new planted tumors after planted into nude mice. The stimulating abilities of the fusion cells on T lymphocytes' proliferations were remarkably increased than their parental dendritic cells.CONCLUSION: The SGC7901 gastric cancer cell-dendritic cell fusion vaccines have much weaker proliferative abilities than their parental cells, but they keep strong abilities to irritate the T lymphocytes and have no abilities to grow into new planted tumors in immunodeficiency animals. These are the biological basis for their antitumor biotherapies.

  14. Macrophages and Dendritic Cells: Partners in Atherogenesis.

    Science.gov (United States)

    Cybulsky, Myron I; Cheong, Cheolho; Robbins, Clinton S

    2016-02-19

    Atherosclerosis is a complex chronic disease. The accumulation of myeloid cells in the arterial intima, including macrophages and dendritic cells (DCs), is a feature of early stages of disease. For decades, it has been known that monocyte recruitment to the intima contributes to the burden of lesion macrophages. Yet, this paradigm may require reevaluation in light of recent advances in understanding of tissue macrophage ontogeny, their capacity for self-renewal, as well as observations that macrophages proliferate throughout atherogenesis and that self-renewal is critical for maintenance of macrophages in advanced lesions. The rate of atherosclerotic lesion formation is profoundly influenced by innate and adaptive immunity, which can be regulated locally within atherosclerotic lesions, as well as in secondary lymphoid organs, the bone marrow and the blood. DCs are important modulators of immunity. Advances in the past decade have cemented our understanding of DC subsets, functions, hematopoietic origin, gene expression patterns, transcription factors critical for differentiation, and provided new tools for study of DC biology. The functions of macrophages and DCs overlap to some extent, thus it is important to reassess the contributions of each of these myeloid cells taking into account strict criteria of cell identification, ontogeny, and determine whether their key roles are within atherosclerotic lesions or secondary lymphoid organs. This review will highlight key aspect of macrophage and DC biology, summarize how these cells participate in different stages of atherogenesis and comment on complexities, controversies, and gaps in knowledge in the field.

  15. Derivation and Utilization of Functional CD8(+) Dendritic Cell Lines.

    Science.gov (United States)

    Pigni, Matteo; Ashok, Devika; Acha-Orbea, Hans

    2016-01-01

    It is notoriously difficult to obtain large quantities of non-activated dendritic cells ex vivo. For this reason, we produced and characterized a mouse model expressing the large T oncogene under the CD11c promoter (Mushi mice), in which CD8α(+) dendritic cells transform after 4 months. We derived a variety of stable cell lines from these primary lines. These cell lines reproducibly share with freshly isolated dendritic cells most surface markers, mRNA and protein expression, and all tested biological functions. Cell lines can be derived from various strains and knockout mice and can be easily transduced with lentiviruses. In this article, we describe the derivation, culture, and lentiviral transduction of these dendritic cell lines.

  16. Unstable Foxp3(+) Regulatory T Cells and Altered Dendritic Cells Are Associated with Lipopolysaccharide-Induced Fetal Loss in Pregnant Interleukin 10-Deficient Mice

    NARCIS (Netherlands)

    Prins, Jelmer R.; Zhang, Bihong; Schjenken, John E.; Guerin, Leigh R.; Barry, Simon C.; Robertson, Sarah A.

    2015-01-01

    Maternal interleukin (IL) 10 deficiency elevates susceptibility to fetal loss induced by the model Toll-like receptor agonist lipopolysaccharide, but the mechanisms are not well elucidated. Here, we show that Il10 null mutant (Il10(-/-)) mice exhibit altered local T cell responses in pregnancy, exhi

  17. Unstable Foxp3(+) Regulatory T Cells and Altered Dendritic Cells Are Associated with Lipopolysaccharide-Induced Fetal Loss in Pregnant Interleukin 10-Deficient Mice

    NARCIS (Netherlands)

    Prins, Jelmer R.; Zhang, Bihong; Schjenken, John E.; Guerin, Leigh R.; Barry, Simon C.; Robertson, Sarah A.

    2015-01-01

    Maternal interleukin (IL) 10 deficiency elevates susceptibility to fetal loss induced by the model Toll-like receptor agonist lipopolysaccharide, but the mechanisms are not well elucidated. Here, we show that Il10 null mutant (Il10(-/-)) mice exhibit altered local T cell responses in pregnancy,

  18. Regulation of AMPA and NMDA receptor-mediated EPSPs in dendritic trees of thalamocortical cells.

    Science.gov (United States)

    Lajeunesse, Francis; Kröger, Helmut; Timofeev, Igor

    2013-01-01

    Two main excitatory synapses are formed at the dendritic arbor of first-order nuclei thalamocortical (TC) neurons. Ascending sensory axons primarily establish contacts at large proximal dendrites, whereas descending corticothalamic fibers form synapses on thin distal dendrites. With the use of a multicomparment computational model based on fully reconstructed TC neurons from the ventroposterolateral nucleus of the cat, we compared local responses at the site of stimulation as well as somatic responses induced by both α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR)- and N-methyl-D-aspartate receptor (NMDAR)-mediated currents. We found that AMPAR-mediated responses, when synapses were located at proximal dendrites, induced a larger depolarization at the level of soma, whereas NMDAR-mediated responses were more efficient for synapses located at distal dendrites. The voltage transfer and transfer impedance were higher for NMDAR than for AMPAR activation at any location. For both types of synaptic current and for both input locations at the dendritic arbor, somatic responses were characterized by a low variability despite the large variability found in local responses in dendrites. The large neurons had overall smaller somatic responses than small neurons, but this relation was not found in local dendritic responses. We conclude that in TC cells, the dendritic location of small synaptic inputs does not play a major role in the amplitude of a somatic response, but the size of the neuron does. The variability of response amplitude between cells was much larger than the variability within cells. This suggests possible functional segregation of TC neurons of different size.

  19. Full restoration of Brucella-infected dendritic cell functionality through Vγ9Vδ2 T helper type 1 crosstalk.

    Directory of Open Access Journals (Sweden)

    Ming Ni

    Full Text Available Vγ9Vδ2 T cells play an important role in the immune response to infectious agents but the mechanisms contributing to this immune process remain to be better characterized. Following their activation, Vγ9Vδ2 T cells develop cytotoxic activity against infected cells, secrete large amounts of cytokines and influence the function of other effectors of immunity, notably cells playing a key role in the initiation of the adaptive immune response such as dendritic cells. Brucella infection dramatically impairs dendritic cell maturation and their capacity to present antigens to T cells. Herein, we investigated whether V T cells have the ability to restore the full functional capacities of Brucella-infected dendritic cells. Using an in vitro multicellular infection model, we showed that: 1/Brucella-infected dendritic cells activate Vγ9Vδ2 T cells through contact-dependent mechanisms, 2/activated Vγ9Vδ2 T cells induce full differentiation into IL-12 producing cells of Brucella-infected dendritic cells with functional antigen presentation activity. Furthermore, phosphoantigen-activated Vγ9Vδ2 T cells also play a role in triggering the maturation process of dendritic cells already infected for 24 h. This suggests that activated Vγ9Vδ2 T cells could be used to modulate the outcome of infectious diseases by promoting an adjuvant effect in dendritic cell-based cellular therapies.

  20. Iron acquisition by Mycobacterium tuberculosis residing within myeloid dendritic cells.

    Science.gov (United States)

    Olakanmi, Oyebode; Kesavalu, Banurekha; Abdalla, Maher Y; Britigan, Bradley E

    2013-12-01

    The pathophysiology of Mycobacterium tuberculosis (M.tb) infection is linked to the ability of the organism to grow within macrophages. Lung myeloid dendritic cells are a newly recognized reservoir of M.tb during infection. Iron (Fe) acquisition is critical for M.tb growth. In vivo, extracellular Fe is chelated to transferrin (TF) and lactoferrin (LF). We previously reported that M.tb replicating in human monocyte-dervied macrophages (MDM) can acquire Fe bound to TF, LF, and citrate, as well as from the MDM cytoplasm. Access of M.tb to Fe may influence its growth in macrophages and dendritic cells. In the present work we confirmed the ability of different strains of M.tb to grow in human myeloid dendritic cells in vitro. Fe acquired by M.tb replicating within dendritic cells from externally added Fe chelates varied with the Fe chelate present in the external media: Fe-citrate > Fe-LF > Fe-TF. Fe acquisition rates from each chelate did not vary over 7 days. M.tb within dendritic cells also acquired Fe from the dendritic cell cytoplasm, with the efficiency of Fe acquisition greater from cytoplasmic Fe sources, regardless of the initial Fe chelate from which that cytoplasmic Fe was derived. Growth and Fe acquisition results with human MDM were similar to those with dendritic cells. M.tb grow and replicate within myeloid dendritic cells in vitro. Fe metabolism of M.tb growing in either MDM or dendritic cells in vitro is influenced by the nature of Fe available and the organism appears to preferentially access cytoplasmic rather than extracellular Fe sources. Whether these in vitro data extend to in vivo conditions should be examined in future studies.

  1. Uptake of donor lymphocytes treated with 8-methoxypsoralen and ultraviolet A light by recipient dendritic cells induces CD4{sup +}CD25{sup +}Foxp3{sup +} regulatory T cells and down-regulates cardiac allograft rejection

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    Zheng, De-Hua [Organ Transplant Center, Chinese PLA 309th Hospital, No. 17A Hei-Shan-Hu Road, Beijing 100091 (China); Dou, Li-Ping [Department of Hematology, Chinese PLA General Hospital, No. 28 Fu-Xing Road, Beijing 100853 (China); Wei, Yu-Xiang; Du, Guo-Sheng; Zou, Yi-Ping; Song, Ji-Yong; Zhu, Zhi-Dong; Cai, Ming; Qian, Ye-Yong [Organ Transplant Center, Chinese PLA 309th Hospital, No. 17A Hei-Shan-Hu Road, Beijing 100091 (China); Shi, Bing-Yi, E-mail: shibingyi@medmail.com.cn [Organ Transplant Center, Chinese PLA 309th Hospital, No. 17A Hei-Shan-Hu Road, Beijing 100091 (China)

    2010-05-14

    Extracorporeal photopheresis (ECP) is an effective immunomodulatory therapy and has been demonstrated to be beneficial for graft-vs-host disease and solid-organ allograft rejection. ECP involves reinfusion of a patient's autologous peripheral blood leukocytes treated ex vivo with 8-methoxypsoralen and UVA light radiation (PUVA). Previous studies focused only on ECP treatment of recipient immune cells. Our study is the first to extend the target of ECP treatment to donor immune cells. The results of in vitro co-culture experiments demonstrate uptake of donor PUVA-treated splenic lymphocytes (PUVA-SPs) by recipient immature dendritic cells (DCs). Phagocytosis of donor PUVA-SPs does not stimulate phenotype maturation of recipient DCs. In the same co-culture system, donor PUVA-SPs enhanced production of interleukin-10 and interferon-{gamma} by recipient DCs and impaired the subsequent capability of recipient DCs to stimulate recipient naive T cells. Phagocytosis of donor PUVA-SP (PUVA-SP DCs) by recipient DCs shifted T-cell responses in favor of T helper 2 cells. Infusion of PUVA-SP DCs inhibited cardiac allograft rejection in an antigen-specific manner and induced CD4{sup +}CD25{sup high}Foxp3{sup +} regulatory T cells. In conclusion, PUVA-SP DCs simultaneously deliver the donor antigen and the regulatory signal to the transplant recipient, and thus can be used to develop a novel DC vaccine for negative immune regulation and immune tolerance induction.

  2. PDIA3 gene induces visceral hypersensitivity in rats with irritable bowel syndrome through the dendritic cell-mediated activation of T cells

    Science.gov (United States)

    Zhuang, Zhaomeng; Zhang, Lu; Wang, Xiaoteng; Tao, Liyuan

    2016-01-01

    This study investigated the mechanism of protein disulfide-isomerase A3 (PDIA3)-induced visceral hypersensitivity in irritable bowel syndrome (IBS). Rats were treated with saline (control), acetic acid and restraint stress (IBS model), empty vector (RNAi control) and PDIA3-RNAi vector (PDIA3-RNAi). Mesenteric lymph node DCs (MLNDCs) and splenic CD4+/CD8+ T cells were isolated for co-cultivation. Compared with control, MLNDCs co-cultured with CD4+ or CD8+ T cells showed an increased ability to promote T cell proliferation and produced more IL-4 or IL-9 secretion. Compare