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Sample records for regulatory dendritic cells

  1. Regulatory dendritic cell therapy: from rodents to clinical application

    OpenAIRE

    Raïch-Regué, Dalia; Glancy, Megan; Thomson, Angus W.

    2013-01-01

    Dendritic cells (DC) are highly-specialized, bone marrow-derived antigen-presenting cells that induce or regulate innate and adaptive immunity. Regulatory or “tolerogenic” DC play a crucial role in maintaining self tolerance in the healthy steady-state. These regulatory innate immune cells subvert naïve or memory T cell responses by various mechanisms. Regulatory DC (DCreg) also exhibit the ability to induce or restore T cell tolerance in many animal models of autoimmune disease or transplant...

  2. 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.

  3. Prospective Clinical Testing of Regulatory Dendritic Cells in Organ Transplantation

    OpenAIRE

    Thomson, Angus W.; Zahorchak, Alan F.; Ezzelarab, Mohamed B.; Butterfield, Lisa H.; Lakkis, Fadi G.; Metes, Diana M.

    2016-01-01

    Dendritic cells (DC) are rare, professional antigen-presenting cells with ability to induce or regulate alloimmune responses. Regulatory DC (DCreg) with potential to down-modulate acute and chronic inflammatory conditions that occur in organ transplantation can be generated in vitro under a variety of conditions. Here, we provide a rationale for evaluation of DCreg therapy in clinical organ transplantation with the goal of promoting sustained, donor-specific hyporesponsiveness, while lowering...

  4. Regulatory dendritic cells in autoimmunity: A comprehensive review.

    Science.gov (United States)

    Liu, Juan; Cao, Xuetao

    2015-09-01

    Dendritic cells (DCs) are professional antigen-presenting cells (APC) with significant phenotypic heterogeneity and functional plasticity. DCs play crucial roles in initiating effective adaptive immune responses for elimination of invading pathogens and also in inducing immune tolerance toward harmless components to maintain immune homeostasis. The regulatory capacity of DCs depends on their immature state and distinct subsets, yet not restricted to the immature state and one specialized subset. The tolerogenicity of DC is controlled by a complex network of environmental signals and cellular intrinsic mechanisms. Regulatory DCs play an important role in the maintenance of immunological tolerance via the induction of T cell unresponsiveness or apoptosis, and generation of regulatory T cells. DCs play essential roles in driving autoimmunity via promoting the activation of effector T cells such as T helper 1 and T helper 17 cells, and/or suppressing the generation of regulatory T cells. Besides, a breakdown of DCs-mediated tolerance due to abnormal environmental signals or breakdown of intrinsic regulatory mechanisms is closely linked with the pathogenesis of autoimmune diseases. Novel immunotherapy taking advantage of the tolerogenic potential of regulatory DCs is being developed for treatment of autoimmune diseases. In this review, we will describe the current understanding on the generation of regulatory DC and the role of regulatory DCs in promoting tolerogenic immune responses and suppressing autoimmune responses. The emerging roles of DCs dysfunction in the pathogenesis of autoimmune diseases and the potential application of regulatory DCs in the treatment of autoimmune diseases will also be discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Regulatory dendritic cell therapy: from rodents to clinical application.

    Science.gov (United States)

    Raïch-Regué, Dalia; Glancy, Megan; Thomson, Angus W

    2014-10-01

    Dendritic cells (DC) are highly-specialized, bone marrow-derived antigen-presenting cells that induce or regulate innate and adaptive immunity. Regulatory or "tolerogenic" DC play a crucial role in maintaining self tolerance in the healthy steady-state. These regulatory innate immune cells subvert naïve or memory T cell responses by various mechanisms. Regulatory DC (DCreg) also exhibit the ability to induce or restore T cell tolerance in many animal models of autoimmune disease or transplant rejection. There is also evidence that adoptive transfer of DCreg can regulate T cell responses in non-human primates and humans. Important insights gained from in vitro studies and animal models have led recently to the development of clinical grade human DCreg, with potential to treat autoimmune disease or enhance transplant survival while reducing patient dependency on immunosuppressive drugs. Phase I trials have been conducted in type-1 diabetes and rheumatoid arthritis, with results that emphasize the feasibility and safety of DCreg therapy. This mini-review will outline how observations made using animal models have been translated into human use, and discuss the challenges faced in further developing this form of regulatory immune cell therapy in the fields of autoimmunity and transplantation. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Minocycline promotes the generation of dendritic cells with regulatory properties.

    Science.gov (United States)

    Kim, Narae; Park, Chan-Su; Im, Sun-A; Kim, Ji-Wan; Lee, Jae-Hee; Park, Young-Jun; Song, Sukgil; Lee, Chong-Kil

    2016-08-16

    Minocycline, which has long been used as a broad-spectrum antibiotic, also exhibits non-antibiotic properties such as inhibition of inflammation and angiogenesis. In this study, we show that minocycline significantly enhances the generation of dendritic cells (DCs) from mouse bone marrow (BM) cells when used together with GM-CSF and IL-4. DCs generated from BM cells in the presence of minocycline (Mino-DCs) demonstrate the characteristics of regulatory DCs. Compared with control DCs, Mino-DCs are resistant to subsequent maturation stimuli, impaired in MHC class II-restricted exogenous Ag presentation, and show decreased cytokine secretion. Mino-DCs also show decreased ability to prime allogeneic-specific T cells, while increasing the expansion of CD4+CD25+Foxp3+ T regulatory cells both in vitro and in vivo. In addition, pretreatment with MOG35-55 peptide-pulsed Mino-DCs ameliorates clinical signs of experimental autoimmune encephalitis induced by MOG peptide injection. Our study identifies minocycline as a new pharmacological agent that could be potentially used to increase the production of regulatory DCs for cell therapy to treat autoimmune disorders, allergy, and transplant rejection.

  7. Prospective Clinical Testing of Regulatory Dendritic Cells in Organ Transplantation.

    Science.gov (United States)

    Thomson, Angus W; Zahorchak, Alan F; Ezzelarab, Mohamed B; Butterfield, Lisa H; Lakkis, Fadi G; Metes, Diana M

    2016-01-01

    Dendritic cells (DC) are rare, professional antigen-presenting cells with ability to induce or regulate alloimmune responses. Regulatory DC (DCreg) with potential to down-modulate acute and chronic inflammatory conditions that occur in organ transplantation can be generated in vitro under a variety of conditions. Here, we provide a rationale for evaluation of DCreg therapy in clinical organ transplantation with the goal of promoting sustained, donor-specific hyporesponsiveness, while lowering the incidence and severity of rejection and reducing patients' dependence on anti-rejection drugs. Generation of donor- or recipient-derived DCreg that suppress T cell responses and prolong transplant survival in rodents or non-human primates has been well-described. Recently, good manufacturing practice (GMP)-grade DCreg have been produced at our Institution for prospective use in human organ transplantation. We briefly review experience of regulatory immune therapy in organ transplantation and describe our experience generating and characterizing human monocyte-derived DCreg. We propose a phase I/II safety study in which the influence of donor-derived DCreg combined with conventional immunosuppression on subclinical and clinical rejection and host alloimmune responses will be examined in detail.

  8. Orchestration of transplantation tolerance by regulatory dendritic cell therapy or in situ targeting of dendritic cells

    Science.gov (United States)

    Morelli, Adrian E.; Thomson, Angus W.

    2014-01-01

    Purpose of review Extensive research in murine transplant models over the past two decades has convincingly demonstrated the ability of regulatory dendritic cells (DCreg) to promote long-term allograft survival. We review important considerations regarding the source of therapeutic DCreg (donor or recipient) and their mode of action, in situ targeting of DCreg, and optimal therapeutic regimens to promote DCreg function. Recent findings Recent studies have defined protocols and mechanisms whereby ex vivo-generated DCreg of donor or recipient origin subvert allogeneic T cell responses and promote long-term organ transplant survival. Particular interest has focused on how donor antigen (Ag) is acquired, processed and presented by autologous DCs, on the stability of DCreg, and on in situ targeting of DC to promote their tolerogenic function. New evidence of the therapeutic efficacy of DCreg in a clinically-relevant non-human primate organ transplant model and production of clinical grade DCreg support early evaluation of DCreg therapy in human graft recipients. Summary We discuss strategies currently used to promote DC tolerogenicity, including DCreg therapy and in situ targeting of DC, with a view to improved understanding of underlying mechanisms and identification of the most promising strategies for therapeutic application. PMID:24926700

  9. Orchestration of transplantation tolerance by regulatory dendritic cell therapy or in-situ targeting of dendritic cells.

    Science.gov (United States)

    Morelli, Adrian E; Thomson, Angus W

    2014-08-01

    Extensive research in murine transplant models over the past two decades has convincingly demonstrated the ability of regulatory dendritic cells (DCregs) to promote long-term allograft survival. We review important considerations regarding the source of therapeutic DCregs (donor or recipient) and their mode of action, in-situ targeting of DCregs, and optimal therapeutic regimens to promote DCreg function. Recent studies have defined protocols and mechanisms whereby ex-vivo-generated DCregs of donor or recipient origin subvert allogeneic T-cell responses and promote long-term organ transplant survival. Particular interest has focused on how donor antigen is acquired, processed and presented by autologous dendritic cells, on the stability of DCregs, and on in-situ targeting of dendritic cells to promote their tolerogenic function. New evidence of the therapeutic efficacy of DCregs in a clinically relevant nonhuman primate organ transplant model and production of clinical grade DCregs support early evaluation of DCreg therapy in human graft recipients. We discuss strategies currently used to promote dendritic cell tolerogenicity, including DCreg therapy and in-situ targeting of dendritic cells, with a view to improved understanding of underlying mechanisms and identification of the most promising strategies for therapeutic application.

  10. Vitamin D3 targets epidermal and dermal dendritic cells for induction of distinct regulatory T cells

    NARCIS (Netherlands)

    van der Aar, Angelic M. G.; Sibiryak, Darya S.; Bakdash, Ghaith; van Capel, Toni M. M.; van der Kleij, Hanneke P. M.; Opstelten, Dirk-Jan E.; Teunissen, Marcel B. M.; Kapsenberg, Martien L.; de Jong, Esther C.

    2011-01-01

    Background: The vitamin D metabolite 1,25(OH) 2D3 (VitD3) is a potent immunosuppressive drug and, among others, is used for topical treatment of psoriasis. A proposed mechanism of VitD3-mediated suppression is priming of dendritic cells (DCs) to induce regulatory T (Treg) cells. Objective:

  11. Mesenchymal stem cells induce mature dendritic cells into a novel Jagged-2-dependent regulatory dendritic cell population.

    Science.gov (United States)

    Zhang, Bin; Liu, Rui; Shi, Dan; Liu, Xingxia; Chen, Yuan; Dou, Xiaowei; Zhu, Xishan; Lu, Chunhua; Liang, Wei; Liao, Lianming; Zenke, Martin; Zhao, Robert C H

    2009-01-01

    Mesenchymal stem cells (MSCs), in addition to their multilineage differentiation, exert immunomodulatory effects on immune cells, even dendritic cells (DCs). However, whether they influence the destiny of full mature DCs (maDCs) remains controversial. Here we report that MSCs vigorously promote proliferation of maDCs, significantly reduce their expression of Ia, CD11c, CD80, CD86, and CD40 while increasing CD11b expression. Interestingly, though these phenotypes clearly suggest their skew to immature status, bacterial lipopolysaccharide (LPS) stimulation could not reverse this trend. Moreover, high endocytosic capacity, low immunogenicity, and strong immunoregulatory function of MSC-treated maDCs (MSC-DCs) were also observed. Furthermore we found that MSCs, partly via cell-cell contact, drive maDCs to differentiate into a novel Jagged-2-dependent regulatory DC population and escape their apoptotic fate. These results further support the role of MSCs in preventing rejection in organ transplantation and treatment of autoimmune disease.

  12. Midkine inhibits inducible regulatory T cell differentiation by suppressing the development of tolerogenic dendritic cells.

    Science.gov (United States)

    Sonobe, Yoshifumi; Li, Hua; Jin, Shijie; Kishida, Satoshi; Kadomatsu, Kenji; Takeuchi, Hideyuki; Mizuno, Tetsuya; Suzumura, Akio

    2012-03-15

    Midkine (MK), a heparin-binding growth factor, reportedly contributes to inflammatory diseases, including Crohn's disease and rheumatoid arthritis. We previously showed that MK aggravates experimental autoimmune encephalomyelitis (EAE) by decreasing regulatory CD4(+)CD25(+)Foxp3(+) T cells (Tregs), a population that regulates the development of autoimmune responses, although the precise mechanism remains uncertain. In this article, we show that MK produced in inflammatory conditions suppresses the development of tolerogenic dendritic cells (DCregs), which drive the development of inducible Treg. MK suppressed DCreg-mediated expansion of the CD4(+)CD25(+)Foxp3(+) Treg population. DCregs expressed significantly higher levels of CD45RB and produced significantly less IL-12 compared with conventional dendritic cells. However, MK downregulated CD45RB expression and induced IL-12 production by reducing phosphorylated STAT3 levels via src homology region 2 domain-containing phosphatase-2 in DCreg. Inhibiting MK activity with anti-MK RNA aptamers, which bind to the targeted protein to suppress the function of the protein, increased the numbers of CD11c(low)CD45RB(+) dendritic cells and Tregs in the draining lymph nodes and suppressed the severity of EAE, an animal model of multiple sclerosis. Our results also demonstrated that MK was produced by inflammatory cells, in particular, CD4(+) T cells under inflammatory conditions. Taken together, these results suggest that MK aggravates EAE by suppressing DCreg development, thereby impairing the Treg population. Thus, MK is a promising therapeutic target for various autoimmune diseases.

  13. Phenotypic and functional markers for 1alpha,25-dihydroxyvitamin D(3)-modified regulatory dendritic cells

    DEFF Research Database (Denmark)

    Pedersen, A W; Holmstrøm, K; Jensen, S S

    2009-01-01

    The clinical use of dendritic cells (DCs) to induce antigen-specific immune tolerance has been hampered by the lack of a widely acknowledged method for generating human regulatory DCs but even more so by the non-existence of reliable markers. Thus, we set out to find reliable markers that can...... CD14 and reduced CD1a on the cell surface. These VD3-treated DCs exert a long-lasting inefficient T cell stimulation and induce T cell hyporesponsiveness with regulatory potential. Importantly, such VD3-treated DCs were readily distinguishable from untreated DCs by low levels of interleukin-23...

  14. The Effect of Traditional Chinese Formula Danchaiheji on the Differentiation of Regulatory Dendritic Cells

    Directory of Open Access Journals (Sweden)

    Yingxi Li

    2016-01-01

    Full Text Available Recently, regulatory dendritic cells (DCregs, a newly described dendritic cell subset with potent immunomodulatory function, have attracted increased attention for their utility in treating immune response-related diseases, such as graft-versus-host disease, hypersensitivity, and autoimmune diseases. Danchaiheji (DCHJ is a traditional Chinese formula that has been used for many years in the clinic. However, whether DCHJ can program dendritic cells towards a regulatory phenotype and the underlying mechanism behind this process remain unknown. Herein, we investigate the effects of traditional Chinese DCHJ on DCregs differentiation and a mouse model of skin transplantation. The current study demonstrates that DCHJ can induce dendritic cells to differentiate into DCregs, which are represented by high CD11b and low CD86 and HLA-DR expression as well as the secretion of IL-10 and TGF-β. In addition, DCHJ inhibited DC migration and T cell proliferation, which correlated with increased IDO expression. Furthermore, DCHJ significantly prolonged skin graft survival time in a mouse model of skin transplantation without any liver or kidney toxicity. The traditional Chinese formula DCHJ has the potential to be a potent immunosuppressive agent with high efficiency and nontoxicity.

  15. The Effect of Traditional Chinese Formula Danchaiheji on the Differentiation of Regulatory Dendritic Cells

    Science.gov (United States)

    Wang, Xiaodong; Tong, Jingzhi; Li, Keqiu; Jing, Yaqing

    2016-01-01

    Recently, regulatory dendritic cells (DCregs), a newly described dendritic cell subset with potent immunomodulatory function, have attracted increased attention for their utility in treating immune response-related diseases, such as graft-versus-host disease, hypersensitivity, and autoimmune diseases. Danchaiheji (DCHJ) is a traditional Chinese formula that has been used for many years in the clinic. However, whether DCHJ can program dendritic cells towards a regulatory phenotype and the underlying mechanism behind this process remain unknown. Herein, we investigate the effects of traditional Chinese DCHJ on DCregs differentiation and a mouse model of skin transplantation. The current study demonstrates that DCHJ can induce dendritic cells to differentiate into DCregs, which are represented by high CD11b and low CD86 and HLA-DR expression as well as the secretion of IL-10 and TGF-β. In addition, DCHJ inhibited DC migration and T cell proliferation, which correlated with increased IDO expression. Furthermore, DCHJ significantly prolonged skin graft survival time in a mouse model of skin transplantation without any liver or kidney toxicity. The traditional Chinese formula DCHJ has the potential to be a potent immunosuppressive agent with high efficiency and nontoxicity. PMID:27525028

  16. Prospective clinical testing of regulatory dendritic cells (DCreg) in organ transplantation

    OpenAIRE

    ANGUS W THOMSON; ALAN F ZAHORCHAK; Mohamed B. Ezzelarab; Lisa H. Butterfield; Fadi G. Lakkis; Diana M Metes

    2016-01-01

    Dendritic cells (DC) are rare, professional antigen-presenting cells with ability to induce or regulate alloimmune responses. Regulatory DC (DCreg) with potential to down-modulate acute and chronic inflammatory conditions that occur in organ transplantation can be generated in vitro under a variety of conditions. Here, we provide a rationale for evaluation of DCreg therapy in clinical organ transplantation with the goal of promoting sustained, donor-specific hyporesponsiveness, while lowering...

  17. Strong adhesion by regulatory T cells induces dendritic cell cytoskeletal polarization and contact-dependent lethargy.

    Science.gov (United States)

    Chen, Jiahuan; Ganguly, Anutosh; Mucsi, Ashley D; Meng, Junchen; Yan, Jiacong; Detampel, Pascal; Munro, Fay; Zhang, Zongde; Wu, Mei; Hari, Aswin; Stenner, Melanie D; Zheng, Wencheng; Kubes, Paul; Xia, Tie; Amrein, Matthias W; Qi, Hai; Shi, Yan

    2017-02-01

    Dendritic cells are targeted by regulatory T (T reg) cells, in a manner that operates as an indirect mode of T cell suppression. In this study, using a combination of single-cell force spectroscopy and structured illumination microscopy, we analyze individual T reg cell-DC interaction events and show that T reg cells exhibit strong intrinsic adhesiveness to DCs. This increased DC adhesion reduces the ability of contacted DCs to engage other antigen-specific cells. We show that this unusually strong LFA-1-dependent adhesiveness of T reg cells is caused in part by their low calpain activities, which normally release integrin-cytoskeleton linkage, and thereby reduce adhesion. Super resolution imaging reveals that such T reg cell adhesion causes sequestration of Fascin-1, an actin-bundling protein essential for immunological synapse formation, and skews Fascin-1-dependent actin polarization in DCs toward the T reg cell adhesion zone. Although it is reversible upon T reg cell disengagement, this sequestration of essential cytoskeletal components causes a lethargic state of DCs, leading to reduced T cell priming. Our results reveal a dynamic cytoskeletal component underlying T reg cell-mediated DC suppression in a contact-dependent manner. © 2017 Chen et al.

  18. iPSC-Derived Regulatory Dendritic Cells Inhibit Allograft Rejection by Generating Alloantigen-Specific Regulatory T Cells

    Directory of Open Access Journals (Sweden)

    Songjie Cai

    2017-05-01

    Full Text Available Regulatory dendritic cell (DCregs-based immunotherapy is a potential therapeutic tool for transplant rejection. We generated DCregs from murine induced pluripotent stem cells (iPSCs, which could remain in a “stable immature stage” even under strong stimulation. Harnessing this characteristic, we hypothesized that iPS-DCregs worked as a negative vaccine to generate regulatorycells (Tregs, and induced donor-specific allograft acceptance. We immunized naive CBA (H-2Kk mice with B6 (H-2Kb iPS-DCregs and found that Tregs (CD4+CD25+FOXP3+ significantly increased in CBA splenocytes. Moreover, immunized CBA recipients permanently accepted B6 cardiac grafts in a donor-specific pattern. We demonstrated mechanistically that donor-type iPS-DCregs triggered transforming growth factor β1 secretion, under which the donor-antigen peptides directed naive CD4+ T cells to differentiate into donor-specific FOXP3+ Tregs instead of into effector T cells in vivo. These findings highlight the potential of iPS-DCregs as a key cell therapy resource in clinical transplantation.

  19. Intravital imaging of donor allogeneic effector and regulatory T cells with host dendritic cells during GVHD.

    Science.gov (United States)

    Lin, Kaifeng Lisa; Fulton, LeShara M; Berginski, Matthew; West, Michelle L; Taylor, Nicholas A; Moran, Timothy P; Coghill, James M; Blazar, Bruce R; Bear, James E; Serody, Jonathan S

    2014-03-06

    Graft-versus-host disease (GVHD) is a systemic inflammatory response due to the recognition of major histocompatibility complex disparity between donor and recipient after hematopoietic stem cell transplantation (HSCT). T-cell activation is critical to the induction of GVHD, and data from our group and others have shown that regulatory T cells (Tregs) prevent GVHD when given at the time of HSCT. Using multiphoton laser scanning microscopy, we examined the single cell dynamics of donor T cells and dendritic cells (DCs) with or without Tregs postallogeneic transplantation. We found that donor conventional T cells (Tcons) spent very little time screening host DCs. Tcons formed stable contacts with DCs very early after transplantation and only increased velocity in the lymph node at 20 hours after transplant. We also observed that Tregs reduced the interaction time between Tcons and DCs, which was dependent on the generation of interleukin 10 by Tregs. Imaging using inducible Tregs showed similar disruption of Tcon-DC contact. Additionally, we found that donor Tregs induce host DC death and down-regulate surface proteins required for donor T-cell activation. These data indicate that Tregs use multiple mechanisms that affect host DC numbers and function to mitigate acute GVHD.

  20. What Are the Molecules Involved in Regulatory T-Cells Induction by Dendritic Cells in Cancer?

    Directory of Open Access Journals (Sweden)

    Rodrigo Nalio Ramos

    2013-01-01

    Full Text Available Dendritic cells (DCs are essential for the maintenance of homeostasis in the organism, and they do that by modulating lymphocyte priming, expansion, and response patterns according to signals they receive from the environment. The induction of suppressive lymphocytes by DCs is essential to hinder the development of autoimmune diseases but can be reverted against homeostasis when in the context of neoplasia. In this setting, the induction of suppressive or regulatory T cells contributes to the establishment of a state of tolerance towards the tumor, allowing it to grow unchecked by an otherwise functional immune system. Besides affecting its local environment, tumor also has been described as potent sources of anti-inflammatory/suppressive factors, which may act systemically, generating defects in the differentiation and maturation of immune cells, far beyond the immediate vicinity of the tumor mass. Cytokines, as IL-10 and TGF-beta, as well as cell surface molecules like PD-L1 and ICOS seem to be significantly involved in the redirection of DCs towards tolerance induction, and recent data suggest that tumor cells may, indeed, modulate distinct DCs subpopulations through the involvement of these molecules. It is to be expected that the identification of such molecules should provide molecular targets for more effective immunotherapeutic approaches to cancer.

  1. Regulatory dendritic cell infusion prolongs kidney allograft survival in non-human primates

    OpenAIRE

    Ezzelarab, M.; Zahorchak, A.F.; Lu, L.; Morelli, A.E.; Chalasani, G.; Demetris, A.J.; Lakkis, F.G.; Wijkstrom, M.; Murase, N.; Humar, A.; Shapiro, R.; Cooper, D.K.C.; Thomson, A.W.

    2013-01-01

    We examined the influence of regulatory dendritic cells (DCreg), generated from cytokine-mobilized donor blood monocytes in vitamin D3 and IL-10, on renal allograft survival in a clinically-relevant rhesus macaque model. DCreg expressed low MHC class II and costimulatory molecules, but comparatively high levels of programmed death ligand-1 (B7-H1), and were resistant to pro-inflammatory cytokine-induced maturation. They were infused intravenously (3.5–10×106/kg), together with the B7-CD28 cos...

  2. Regulatory dendritic cell infusion prolongs kidney allograft survival in non-human primates

    Science.gov (United States)

    Ezzelarab, M.; Zahorchak, A.F.; Lu, L.; Morelli, A.E.; Chalasani, G.; Demetris, A.J.; Lakkis, F.G.; Wijkstrom, M.; Murase, N.; Humar, A.; Shapiro, R.; Cooper, D.K.C.; Thomson, A.W.

    2014-01-01

    We examined the influence of regulatory dendritic cells (DCreg), generated from cytokine-mobilized donor blood monocytes in vitamin D3 and IL-10, on renal allograft survival in a clinically-relevant rhesus macaque model. DCreg expressed low MHC class II and costimulatory molecules, but comparatively high levels of programmed death ligand-1 (B7-H1), and were resistant to pro-inflammatory cytokine-induced maturation. They were infused intravenously (3.5–10×106/kg), together with the B7-CD28 costimulation blocking agent CTLA4Ig, 7 days before renal transplantation. CTLA4Ig was given for up to 8 weeks and rapamycin, started on day −2, was maintained with tapering of blood levels until full withdrawal at 6 months. Median graft survival time was 39.5 days in control monkeys (no DC infusion; n=6) and 113.5 days (pDCreg-treated animals (n=6). No adverse events were associated with DCreg infusion, and there was no evidence of induction of host sensitization based on circulating donor-specific alloantibody levels. Immunologic monitoring also revealed regulation of donor-reactive memory CD95+ T cells and reduced memory/regulatory T cell ratios in DCreg-treated monkeys compared with controls. Termination allograft histology showed moderate combined T cell- and Ab-mediated rejection in both groups. These findings justify further pre-clinical evaluation of DCreg therapy and their therapeutic potential in organ transplantation. PMID:23758811

  3. Prospective clinical testing of regulatory dendritic cells (DCreg in organ transplantation

    Directory of Open Access Journals (Sweden)

    ANGUS W THOMSON

    2016-01-01

    Full Text Available Dendritic cells (DC are rare, professional antigen-presenting cells with ability to induce or regulate alloimmune responses. Regulatory DC (DCreg with potential to down-modulate acute and chronic inflammatory conditions that occur in organ transplantation can be generated in vitro under a variety of conditions. Here, we provide a rationale for evaluation of DCreg therapy in clinical organ transplantation with the goal of promoting sustained, donor-specific hyporesponsiveness, while lowering the incidence and severity of rejection and reducing patients’ dependence on anti-rejection drugs. Generation of donor- or recipient-derived DCreg that suppress T cell responses and prolong transplant survival in rodents or non-human primates has been well-described. Recently, good manufacturing practice (GMP-grade DCreg have been produced at our Institution for prospective use in human organ transplantation. We briefly review experience of regulatory immune therapy in organ transplantation and describe our experience generating and characterizing human monocyte-derived DCreg. We propose a phase I/II safety study in which the influence of donor-derived DCreg combined with conventional immunosuppression on subclinical and clinical rejection and host alloimmune responses will be examined in detail.

  4. Classical dendritic cells are required for dietary antigen-mediated peripheral regulatory T cell and tolerance induction

    Science.gov (United States)

    Esterházy, Daria; Loschko, Jakob; London, Mariya; Jove, Veronica; Oliveira, Thiago Y.; Mucida, Daniel

    2016-01-01

    Oral tolerance prevents pathological inflammatory responses towards innocuous foreign antigens via peripheral regulatory T cells (pTreg cells). However, whether a particular subset of antigen-presenting cells (APCs) is required during dietary antigen exposure to instruct naïve CD4+ T cells to differentiate into pTreg cells has not been defined. Using myeloid lineage-specific APC depletion in mice, we found that monocyte-derived APCs are dispensable, while classical dendritic cells (cDCs) are critical for pTreg cell induction and oral tolerance. CD11b− cDCs from the gut-draining lymph nodes efficiently induced pTreg cells, and conversely, loss of IRF8-dependent CD11b− cDCs impaired their polarization, although oral tolerance remained intact. These data reveal the hierarchy of cDC subsets in pTreg cell induction and their redundancy during oral tolerance development. PMID:27019226

  5. Regulatory dendritic cell infusion prolongs kidney allograft survival in nonhuman primates.

    Science.gov (United States)

    Ezzelarab, M B; Zahorchak, A F; Lu, L; Morelli, A E; Chalasani, G; Demetris, A J; Lakkis, F G; Wijkstrom, M; Murase, N; Humar, A; Shapiro, R; Cooper, D K C; Thomson, A W

    2013-08-01

    We examined the influence of regulatory dendritic cells (DCreg), generated from cytokine-mobilized donor blood monocytes in vitamin D3 and IL-10, on renal allograft survival in a clinically relevant rhesus macaque model. DCreg expressed low MHC class II and costimulatory molecules, but comparatively high levels of programmed death ligand-1 (B7-H1), and were resistant to pro-inflammatory cytokine-induced maturation. They were infused intravenously (3.5-10 × 10(6) /kg), together with the B7-CD28 costimulation blocking agent CTLA4Ig, 7 days before renal transplantation. CTLA4Ig was given for up to 8 weeks and rapamycin, started on Day -2, was maintained with tapering of blood levels until full withdrawal at 6 months. Median graft survival time was 39.5 days in control monkeys (no DC infusion; n = 6) and 113.5 days (p DCreg-treated animals (n = 6). No adverse events were associated with DCreg infusion, and there was no evidence of induction of host sensitization based on circulating donor-specific alloantibody levels. Immunologic monitoring also revealed regulation of donor-reactive memory CD95(+) T cells and reduced memory/regulatory T cell ratios in DCreg-treated monkeys compared with controls. Termination allograft histology showed moderate combined T cell- and Ab-mediated rejection in both groups. These findings justify further preclinical evaluation of DCreg therapy and their therapeutic potential in organ transplantation. © Copyright 2013 The American Society of Transplantation and the American Society of Transplant Surgeons.

  6. Indoleamine 2,3-dioxygenase-expressing leukemic dendritic cells impair a leukemia-specific immune response by inducing potent T regulatory cells.

    Science.gov (United States)

    Curti, Antonio; Trabanelli, Sara; Onofri, Chiara; Aluigi, Michela; Salvestrini, Valentina; Ocadlikova, Darina; Evangelisti, Cecilia; Rutella, Sergio; De Cristofaro, Raimondo; Ottaviani, Emanuela; Baccarani, Michele; Lemoli, Roberto M

    2010-12-01

    The immunoregulatory enzyme indoleamine 2,3-dioxygenase, which catalyzes the conversion of tryptophan into kynurenine, is expressed in a significant subset of patients with acute myeloid leukemia, resulting in the inhibition of T-cell proliferation and the induction of regulatory T cells. Acute myeloid leukemia cells can be differentiated into dendritic cells, which have increased immunogenicity and have been proposed as vaccines against leukemia. Leukemic dendritic cells were generated from acute myeloid leukemia cells and used as stimulators in functional assays, including the induction of regulatory T cells. Indoleamine 2,3-dioxygenase expression in leukemic dendritic cells was evaluated at molecular, protein and enzymatic levels. We demonstrate that, after differentiation into dendritic cells, both indoleamine 2,3-dioxygenase-negative and indoleamine 2,3-dioxygenase-positive acute myeloid leukemia samples show induction and up-regulation of indoleamine 2,3-dioxygenase gene and protein, respectively. Indoleamine 2,3-dioxygenase-positive acute myeloid leukemia dendritic cells catabolize tryptophan into kynurenine metabolite and inhibit T-cell proliferation through an indoleamine 2,3-dioxygenase-dependent mechanism. Moreover, indoleamine 2,3-dioxygenase-positive leukemic dendritic cells increase the number of allogeneic and autologous CD4(+)CD25(+) Foxp3(+) T cells and this effect is completely abrogated by the indoleamine 2,3-dioxygenase-inhibitor, 1-methyl tryptophan. Purified CD4(+)CD25(+) T cells obtained from co-culture with indoleamine 2,3-dioxygenase-positive leukemic dendritic cells act as regulatory T cells as they inhibit naive T-cell proliferation and impair the complete maturation of normal dendritic cells. Importantly, leukemic dendritic cell-induced regulatory T cells are capable of in vitro suppression of a leukemia-specific T cell-mediated immune response, directed against the leukemia-associated antigen, Wilms' tumor protein. These data identify

  7. Renal Allograft Survival in Nonhuman Primates Infused With Donor Antigen-Pulsed Autologous Regulatory Dendritic Cells.

    Science.gov (United States)

    Ezzelarab, M B; Raich-Regue, D; Lu, L; Zahorchak, A F; Perez-Gutierrez, A; Humar, A; Wijkstrom, M; Minervini, M; Wiseman, R W; Cooper, D K C; Morelli, A E; Thomson, A W

    2017-06-01

    Systemic administration of autologous regulatory dendritic cells (DCreg; unpulsed or pulsed with donor antigen [Ag]), prolongs allograft survival and promotes transplant tolerance in rodents. Here, we demonstrate that nonhuman primate (NHP) monocyte-derived DCreg preloaded with cell membrane vesicles from allogeneic peripheral blood mononuclear cells induce T cell hyporesponsiveness to donor alloantigen (alloAg) in vitro. These donor alloAg-pulsed autologous DCreg (1.4-3.6 × 10 6 /kg) were administered intravenously, 1 day before MHC-mismatched renal transplantation to rhesus monkeys treated with costimulation blockade (cytotoxic T lymphocyte Ag 4 immunoglobulin [CTLA4] Ig) and tapered rapamycin. Prolongation of graft median survival time from 39.5 days (no DCreg infusion; n = 6 historical controls) and 29 days with control unpulsed DCreg (n = 2), to 56 days with donor Ag-pulsed DCreg (n = 5) was associated with evidence of modulated host CD4 + and CD8 + T cell responses to donor Ag and attenuation of systemic IL-17 production. Circulating anti-donor antibody (Ab) was not detected until CTLA4 Ig withdrawal. One monkey treated with donor Ag-pulsed DCreg rejected its graft in association with progressively elevated anti-donor Ab, 525 days posttransplant (160 days after withdrawal of immunosuppression). These findings indicate a modest but not statistically significant beneficial effect of donor Ag-pulsed autologous DCreg infusion on NHP graft survival when administered with a minimal immunosuppressive drug regimen. © 2016 The American Society of Transplantation and the American Society of Transplant Surgeons.

  8. Effector and regulatory dendritic cells display distinct patterns of miRNA expression.

    Science.gov (United States)

    Lombardi, Vincent; Luce, Sonia; Moussu, Hélène; Morizur, Lise; Gueguen, Claire; Neukirch, Catherine; Chollet-Martin, Sylvie; Mascarell, Laurent; Aubier, Michel; Baron-Bodo, Véronique; Moingeon, Philippe

    2017-09-01

    MicroRNAs (miRNAs) contribute to the regulation of dendritic cell (DC) polarization, thereby influencing the balance of adaptive immune responses. Herein, we studied the expression of miRNAs in polarized DCs and analyzed whether expression of these miRNAs could be associated with allergic rhinitis and allergen immunotherapy (AIT) outcome. Using specific culture conditions, we differentiated immature human monocyte-derived DCs into DC1, DC2, and DCreg subsets (supporting the differentiation of T H 1, T H 2 or regulatory T cells, respectively). Profiling of miRNA expression was performed in these DC subpopulations using microarrays. Levels of miRNAs specific for polarized DCs were then evaluated in a cohort of 58 patients with allergic rhinitis and 25 non-allergic controls, as well as in samples from 30 subjects treated with sublingual grass pollen tablets or placebo for four months. We successfully identified 16 miRNAs differentially regulated between immature DCs, DC1, DC2, and DCreg cells. In allergic rhinoconjunctivitis patients, the expression of two of those miRNAs (miR-132 and miR-155), was down-regulated compared to non-allergic individuals. However, the levels of these miRNAs were not significantly modified following four months of grass pollen immunotherapy. Studying polarized DCs and clinical samples from subjects with or without allergic rhinoconjunctivitis, we demonstrated that the expression of two miRNAs linked to effector DCs (i.e., DC1 and/or DC2 cells), was reduced in the blood of patients with allergic rhinoconjunctivitis. Nevertheless, these miRNAs did not represent relevant biomarkers to predict or follow-up AIT efficacy. © 2017 The Authors. Immunity, Inflammation and Disease Published by John Wiley & Sons Ltd.

  9. Resistin enhances the expansion of regulatory T cells through modulation of dendritic cells

    Directory of Open Access Journals (Sweden)

    Han Seung

    2010-06-01

    Full Text Available Abstract Background Resistin, a member of adipokine family, is known to be involved in the modulation of immune responses including inflammatory activity. Interestingly, resistin is secreted by adipocytes in mice and rats whereas it is secreted by leukocytes in humans. However, the mechanism behind the effect of resistin on the expansion of regulatory T cells (Tregs remains poorly understood. Therefore, we examined regulatory effect of resistin on the induction and cellular modification of Tregs. Results Both protein and mRNA expression of FoxP3, a representative marker of Tregs, increased in a dose-dependent manner when peripheral blood mononuclear cells were treated with resistin. At the same time, resistin had no direct effect on the induction of FoxP3 in CD4+ T cells, suggesting an indirect role through other cells type(s. Since DCs are an important player in the differentiation of T cells, we focused on the role of DCs in the modulation of Tregs by resistin. Resistin suppressed the expression of interferon regulatory factor (IRF-1 and its target cytokines, IL-6, IL-23p19 and IL-12p40, in DCs. Furthermore, FoxP3 expression is increased in CD4+ T cells when co-cultured with DCs and concomitantly treated with resistin. Conclusion Our results suggest that resistin induces expansion of functional Tregs only when co-cultured with DCs.

  10. WNT16B from Ovarian Fibroblasts Induces Differentiation of Regulatory T Cells through β-Catenin Signal in Dendritic Cells

    Directory of Open Access Journals (Sweden)

    Cong-Cong Shen

    2014-07-01

    Full Text Available Treatment for cancer can induce a series of secreted factors into the tumor microenvironment, which can affect cancer progression. Wingless-type MMTV (mouse mammary tumor virus integration site 16B (WNT16B is a new member of the WNT family and has been reported to play growth-related roles in previous studies. In this study, we found WNT16B could be expressed and secreted into the microenvironment by human ovarian fibroblasts after DNA damage-associated treatment, including chemotherapy drugs and radiation. We also demonstrated that fibroblast-derived WNT16B could result in accumulation of β-catenin in dendritic cells and secretion of interleukin-10 (IL-10 and transforming growth factor beta (TGF-β, which contributed to the differentiation of regulatory T cells in a co-culture environment. These results shed light on the roles of WNT16B in immune regulation, especially in regard to cancer treatment.

  11. Induction of T helper 3 regulatory cells by dendritic cells infected with porcine reproductive and respiratory syndrome virus

    International Nuclear Information System (INIS)

    Silva-Campa, Erika; Flores-Mendoza, Lilian; Resendiz, Monica; Pinelli-Saavedra, Araceli; Mata-Haro, Veronica; Mwangi, Waithaka; Hernandez, Jesus

    2009-01-01

    Delayed development of virus-specific immune response has been observed in pigs infected with the porcine reproductive and respiratory syndrome virus (PRRSV). Several studies support the hypothesis that the PRRSV is capable of modulating porcine immune system, but the mechanisms involved are yet to be defined. In this study, we evaluated the induction of T regulatory cells by PRRSV-infected dendritic cells (DCs). Our results showed that PRRSV-infected DCs significantly increased Foxp3 + CD25 + T cells, an effect that was reversible by IFN-α treatment, and this outcome was reproducible using two distinct PRRSV strains. Analysis of the expressed cytokines suggested that the induction of Foxp3 + CD25 + T cells is dependent on TGF-β but not IL-10. In addition, a significant up-regulation of Foxp3 mRNA, but not TBX21 or GATA3, was detected. Importantly, our results showed that the induced Foxp3 + CD25 + T cells were able to suppress the proliferation of PHA-stimulated PBMCs. The T cells induced by the PRRSV-infected DCs fit the Foxp3 + CD25 + T helper 3 (Th3) regulatory cell phenotype described in the literature. The induction of this cell phenotype depended, at least in part, on PRRSV viability because IFN-α treatment or virus inactivation reversed these effects. In conclusion, this data supports the hypothesis that the PRRSV succeeds to establish and replicate in porcine cells early post-infection, in part, by inducing Th3 regulatory cells as a mechanism of modulating the porcine immune system.

  12. Intradermal application of vitamin D3 increases migration of CD14+ dermal dendritic cells and promotes the development of Foxp3+ regulatory T cells

    NARCIS (Netherlands)

    Bakdash, Ghaith; Schneider, Laura P.; van Capel, Toni M. M.; Kapsenberg, Martien L.; Teunissen, Marcel B. M.; de Jong, Esther C.

    2013-01-01

    The active form of vitamin D3 (VitD) is a potent immunosuppressive drug. Its effects are mediated in part through dendritic cells (DCs) that promote the development of regulatory T cells (Tregs). However, it remains elusive how VitD would influence the different human skin DC subsets, e.g.,

  13. Oral dendritic cells mediate antigen-specific tolerance by stimulating TH1 and regulatory CD4+ T cells.

    Science.gov (United States)

    Mascarell, Laurent; Lombardi, Vincent; Louise, Anne; Saint-Lu, Nathalie; Chabre, Henri; Moussu, Hélène; Betbeder, Didier; Balazuc, Anne-Marie; Van Overtvelt, Laurence; Moingeon, Philippe

    2008-09-01

    A detailed characterization of oral antigen-presenting cells is critical to improve second-generation sublingual allergy vaccines. To characterize oral dendritic cells (DCs) within lingual and buccal tissues from BALB/c mice with respect to their surface phenotype, distribution, and capacity to polarize CD4(+) T-cell responses. In situ analysis of oral DCs was performed by immunohistology. Purified DCs were tested in vitro for their capacity to capture, process, and present the ovalbumin antigen to naive CD4(+) T cells. In vivo priming of ovalbumin-specific T cells adoptively transferred to BALB/c mice was analyzed by cytofluorometry in cervical lymph nodes after sublingual administration of mucoadhesive ovalbumin. Three subsets of oral DCs with a distinct tissue distribution were identified: (1) a minor subset of CD207(+) Langerhans cells located in the mucosa itself, (2) a major subpopulation of CD11b(+)CD11c(-) and CD11b(+)CD11c(+) myeloid DCs at the mucosal/submucosal interface, and (3) B220(+)120G8(+) plasmacytoid DCs found in submucosal tissues. Purified myeloid and plasmacytoid oral DCs capture and process the antigen efficiently and are programmed to elicit IFN-gamma and/or IL-10 production together with a suppressive function in naive CD4(+) T cells. Targeting the ovalbumin antigen to oral DCs in vivo by using mucoadhesive particles establishes tolerance in the absence of cell depletion through the stimulation of IFN-gamma and IL-10-producing CD4(+) regulatory T cells in cervical lymph nodes. The oral immune system is composed of various subsets of tolerogenic DCs organized in a compartmentalized manner and programmed to induce T(H)1/regulatory T-cell responses.

  14. Effector and regulatory dendritic cells display distinct patterns of miRNA expression

    OpenAIRE

    Lombardi, Vincent; Luce, Sonia; Moussu, H?l?ne; Morizur, Lise; Gueguen, Claire; Neukirch, Catherine; Chollet?Martin, Sylvie; Mascarell, Laurent; Aubier, Michel; Baron?Bodo, V?ronique; Moingeon, Philippe

    2017-01-01

    Abstract Introduction MicroRNAs (miRNAs) contribute to the regulation of dendritic cell (DC) polarization, thereby influencing the balance of adaptive immune responses. Herein, we studied the expression of miRNAs in polarized DCs and analyzed whether expression of these miRNAs could be associated with allergic rhinitis and allergen immunotherapy (AIT) outcome. Method Using specific culture conditions, we differentiated immature human monocyte?derived DCs into DC1, DC2, and DCreg subsets (supp...

  15. Dendritic cell vaccines.

    Science.gov (United States)

    Mosca, Paul J; Lyerly, H Kim; Clay, Timothy M; Morse, Michael A; Lyerly, H Kim

    2007-05-01

    Dendritic cells are antigen-presenting cells that have been shown to stimulate tumor antigen-specific T cell responses in preclinical studies. Consequently, there has been intense interest in developing dendritic cell based cancer vaccines. A variety of methods for generating dendritic cells, loading them with tumor antigens, and administering them to patients have been described. In recent years, a number of early phase clinical trials have been performed and have demonstrated the safety and feasibility of dendritic cell immunotherapies. A number of these trials have generated valuable preliminary data regarding the clinical and immunologic response to DC-based immunotherapy. The emphasis of dendritic cell immunotherapy research is increasingly shifting toward the development of strategies to increase the potency of dendritic cell vaccine preparations.

  16. Indoleamine 2,3-dioxygenase-expressing leukemic dendritic cells impair a leukemia-specific immune response by inducing potent T regulatory cells

    OpenAIRE

    Curti, A; Trabanelli, S; Onofri, C; Aluigi, M; Salvestrini, V; Ocadlikova, D; Evangelisti, C; Rutella, S; De Cristofaro, R; Ottaviani, E; Baccarani, M; Lemoli, RM

    2010-01-01

    Background: The immunoregulatory enzyme indoleamine 2,3-dioxygenase, which catalyzes the conversion of tryptophan into kynurenine, is expressed in a significant subset of patients with acute myeloid leukemia, resulting in the inhibition of T-cell proliferation and the induction of regulatory T cells. Acute myeloid leukemia cells can be differentiated into dendritic cells, which have increased immunogenicity and have been proposed as vaccines against leukemia.\\ud Design and Methods: Leukemic d...

  17. Changes in peripheral blood level of regulatory T cells in patients with malignant melanoma during treatment with dendritic cell vaccination and low-dose IL-2

    DEFF Research Database (Denmark)

    Bjoern, J; Brimnes, M K; Andersen, M H

    2011-01-01

    In this study, changes in peripheral blood regulatory T cell (Treg) levels were evaluated in 46 progressive patients with melanoma treated with a dendritic cell-based vaccine and concomitant low-dose IFN-α and IL-2. The regulatory subset of CD4 T cells, characterized by CD25(high......) , was prospectively analysed in fresh blood, and treatment-associated quantitative and qualitative changes were analysed. By the 4th vaccine, patients showed a marked increase in CD4+ CD25(high) T cell subset from 6% to 22% (P...

  18. Changes in peripheral blood level of regulatory T cells in patients with malignant melanoma during treatment with dendritic cell vaccination and low-dose IL-2

    DEFF Research Database (Denmark)

    Bjoern, J; Brimnes, M K; Andersen, M H

    2011-01-01

    In this study, changes in peripheral blood regulatory T cell (Treg) levels were evaluated in 46 progressive patients with melanoma treated with a dendritic cell-based vaccine and concomitant low-dose IFN-a and IL-2. The regulatory subset of CD4 T cells, characterized by CD25(high......) , was prospectively analysed in fresh blood, and treatment-associated quantitative and qualitative changes were analysed. By the 4th vaccine, patients showed a marked increase in CD4+ CD25(high) T cell subset from 6% to 22% (P...

  19. Direct regulatory immune activity of lactic acid bacteria on Der p 1-pulsed dendritic cells from allergic patients.

    Science.gov (United States)

    Pochard, Pierre; Hammad, Hamida; Ratajczak, Céline; Charbonnier-Hatzfeld, Anne-Sophie; Just, Nicolas; Tonnel, André-Bernard; Pestel, Joël

    2005-07-01

    Lactic acid bacteria (LAB) are suggested to play a regulatory role in the development of allergic reactions. However, their potential effects on dendritic cells (DCs) directing the immune polarization remain unclear. The immunologic effect of Lactobacillus plantarum NCIMB 8826 (LAB1) on monocyte-derived dendritic cells (MD-DCs) from patients allergic to house dust mite was evaluated. MD-DCs were stimulated for 24 hours with the related allergen Der p 1 in the presence or absence of LAB1. Cell-surface markers were assessed by means of FACS analysis, and the key polarizing cytokines IL-12 and IL-10 were quantified. The subsequent regulatory effect of pulsed MD-DCs on naive or memory T cells was evaluated by determining the T-cell cytokine profile. LAB1 induced the maturation of MD-DCs, even if pulsed with Der p 1. Interestingly, after incubation with LAB1 and Der p 1, MD-DCs produced higher amounts of IL-12 than Der p 1-pulsed DCs. Indeed, the T H 2 cytokine (IL-4 and IL-5) production observed when naive or memory autologous T cells were cocultured with Der p 1-pulsed MD-DCs was highly reduced in the presence of LAB1. Finally, in contrast to naive or memory T cells exposed once to Der p 1-pulsed DCs, T cells stimulated by MD-DCs pulsed with Der p 1 and LAB1 failed to produce T H 2 cytokines in response to a new stimulation with Der p 1-pulsed DCs. Thus in the presence of LAB1, MD-DCs from allergic patients tend to reorientate the T-cell response toward a beneficial T H 1 profile.

  20. Corruption of dendritic cell antigen presentation during acute GVHD leads to regulatory T-cell failure and chronic GVHD.

    Science.gov (United States)

    Leveque-El Mouttie, Lucie; Koyama, Motoko; Le Texier, Laetitia; Markey, Kate A; Cheong, Melody; Kuns, Rachel D; Lineburg, Katie E; Teal, Bianca E; Alexander, Kylie A; Clouston, Andrew D; Blazar, Bruce R; Hill, Geoffrey R; MacDonald, Kelli P A

    2016-08-11

    Chronic graft-versus-host disease (cGVHD) is a major cause of late mortality following allogeneic bone marrow transplantation (BMT) and is characterized by tissue fibrosis manifesting as scleroderma and bronchiolitis obliterans. The development of acute GVHD (aGVHD) is a powerful clinical predictor of subsequent cGVHD, suggesting that aGVHD may invoke the immunologic pathways responsible for cGVHD. In preclinical models in which sclerodermatous cGVHD develops after a preceding period of mild aGVHD, we show that antigen presentation within major histocompatibility complex (MHC) class II of donor dendritic cells (DCs) is markedly impaired early after BMT. This is associated with a failure of regulatory T-cell (Treg) homeostasis and cGVHD. Donor DC-restricted deletion of MHC class II phenocopied this Treg deficiency and cGVHD. Moreover, specific depletion of donor Tregs after BMT also induced cGVHD, whereas adoptive transfer of Tregs ameliorated it. These data demonstrate that the defect in Treg homeostasis seen in cGVHD is a causative lesion and is downstream of defective antigen presentation within MHC class II that is induced by aGVHD. © 2016 by The American Society of Hematology.

  1. Cutaneous infiltration of plasmacytoid dendritic cells and T regulatory cells in skin lesions of polymorphic light eruption.

    Science.gov (United States)

    Rossi, M T; Arisi, M; Lonardi, S; Lorenzi, L; Ungari, M; Serana, F; Fusano, M; Moggio, E; Calzavara-Pinton, P G; Venturini, M

    2018-02-11

    Polymorphic light eruption (PLE) is the most common autoimmune photodermatosis. Plasmacytoid dendritic cells (PDCs) are important mediators of innate antimicrobial immunity involved in the pathogenesis of many inflammatory skin diseases. In addition to PDCs, regulatory T cells (Tregs) are involved in controlling inflammation and adaptive immunity in skin by their immunosuppressive capacity. The aim of this study was to investigate the presence of PDCs and Tregs in photoexposed skin from PLE compared to healthy skin. Patients with PLE diagnosis and healthy controls were recruited and underwent a photoprovocative test. A 4-mm punch biopsy was taken from the site of positive photoprovocation test reaction, and immunohistochemistry for BDCA2 as marker for PDCs, CD4 and FOXP3 as markers for Tregs was performed. Double immunostain for FOXP3 and CD4 was performed as well. Absolute counts for CD4, BDCA2 and FOXP3 were performed in at least 5 High Power Fields (HPF). Percentage of CD4-, BDCA2- and CD4FOXP3-positive cells over the total inflammatory infiltrate was assessed for each case. We enrolled 23 patients and controls. BDCA2+ cells were present in 91.3% of PLE skin samples and 100% of healthy volunteer. Both in PLE patients and healthy controls, PDCs distribution was mainly dermic (P PLE patients (P PLE patients and healthy controls, Tregs distribution was mainly dermic (P PLE patients compared to controls (P PLE, and dermal distribution of PDCs in PLE skin biopsies seems to confirm a possible overlap with cutaneous lupus erythematosus (CLE). © 2018 European Academy of Dermatology and Venereology.

  2. Regulatory dendritic cells for promotion of liver transplant operational tolerance: Rationale for a clinical trial and accompanying mechanistic studies.

    Science.gov (United States)

    Thomson, Angus W; Humar, Abhinav; Lakkis, Fadi G; Metes, Diana M

    2018-05-01

    Dendritic cells (DC) are rare, bone marrow (BM)-derived innate immune cells that critically maintain self-tolerance in the healthy steady-state. Regulatory DC (DCreg) with capacity to suppress allograft rejection and promote transplant tolerance in pre-clinical models can readily be generated from BM precursors or circulating blood monocytes. These DCreg enhance allograft survival via various mechanisms, including promotion of regulatory T cells. In non-human primates receiving minimal immunosuppressive drug therapy (IS), infusion of DCreg of donor origin, one week before transplant, safely prolongs renal allograft survival and selectively attenuates anti-donor CD8 + memory T cell responses in the early post-transplant period. Based on these observations, and in view of the critical need to reduce patient dependence on non-specific IS agents that predispose to cardiometabolic side effects and renal insufficiency, we will conduct a first-in-human safety and preliminary efficacy study of donor-derived DCreg infusion to achieve early (18 months post-transplant) complete IS withdrawal in low-risk, living donor liver transplant recipients receiving standard-of-care IS (mycophenolate mofetil, tacrolimus and steroids). We will test the hypothesis that, although donor-derived DCreg are short-lived, they will induce robust donor-specific T cell hyporesponsiveness. We will examine immunological mechanisms by sequential analysis of blood and tissue samples, incorporating cutting-edge technologies. Copyright © 2017 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

  3. Inhibition effect of B7-H1 gene-modified regulatory dendritic cells on thyroid-associated ophthalmopathy in mice

    Directory of Open Access Journals (Sweden)

    Hua-Xin Chen

    2014-10-01

    Full Text Available AIM:To construct adenovirus vector expressing mice B7-H1 gene, transfect dendritic cells(DCs, and to study the therapeutic effect of modified DC on thyroid-associated ophthalmopathy(TAOin mice.METHODS: We designed and constructed B7-H1 gene adenovirus expression vector, and transfected DCs from mouse bone marrow, tested the phenotype and function of modified DCs, identificated its negative regulation to immune responses. The modified DCs were infected the sicked mice. And then the immunotherapeutic effect of modified DCs to TAO were tested. RESULTS: B7-H1 gene adenovirus vector was constructed and transfected DCs from bone marrow. The titer of the recombinant adenovirus was 1.8×109PFU/mL. B7-H1 gene modified DCs characteristics of regulatory DCs, could inhibit positive immune responses. The inhibition proceeding of TAO into mice infected modified DCs, was obviously prior to the control mice. The gene modified DCs, maybe become the new immunotherapy biological agent to thy TAO.CONCLUSION: We constructed the expression of mouse B7-H1 gene adenovirus expressed vector successfully, transfected DCs,by vector have properties of regulatory DCs, inhibiting positive immune response and the occurrence and development of thyroid eye disease. Gene modified DCs, reveal potent to the treatment of thyroid eye disease.

  4. Characterization of Regulatory Dendritic Cells That Mitigate Acute Graft-versus-Host Disease in Older Mice Following Allogeneic Bone Marrow Transplantation

    OpenAIRE

    Scroggins, Sabrina M.; Olivier, Alicia K.; Meyerholz, David K.; Schlueter, Annette J.

    2013-01-01

    Despite improvements in human leukocyte antigen matching and pharmacologic prophylaxis, acute graft-versus-host disease (GVHD) is often a fatal complication following hematopoietic stem cell transplant (HSCT). Older HSCT recipients experience significantly increased morbidity and mortality compared to young recipients. Prophylaxis with syngeneic regulatory dendritic cells (DCreg) in young bone marrow transplanted (BMT) mice has been shown to decrease GVHD-associated mortality. To evaluate thi...

  5. Dendritic cell neoplasms: an overview.

    Science.gov (United States)

    Kairouz, Sebastien; Hashash, Jana; Kabbara, Wadih; McHayleh, Wassim; Tabbara, Imad A

    2007-10-01

    Dendritic cell neoplasms are rare tumors that are being recognized with increasing frequency. They were previously classified as lymphomas, sarcomas, or histiocytic neoplasms. The World Health Organization (WHO) classifies dendritic cell neoplasms into five groups: Langerhans' cell histiocytosis, Langerhans' cell sarcoma, Interdigitating dendritic cell sarcoma/tumor, Follicular dendritic cell sarcoma/tumor, and Dendritic cell sarcoma, not specified otherwise (Jaffe, World Health Organization classification of tumors 2001; 273-289). Recently, Pileri et al. provided a comprehensive immunohistochemical classification of histiocytic and dendritic cell tumors (Pileri et al., Histopathology 2002;59:161-167). In this article, a concise overview regarding the pathological, clinical, and therapeutic aspects of follicular dendritic, interdigitating dendritic, and Langerhans' cell tumors is presented.

  6. ATP Release from Chemotherapy-Treated Dying Leukemia Cells Elicits an Immune Suppressive Effect by Increasing Regulatory T Cells and Tolerogenic Dendritic Cells.

    Science.gov (United States)

    Lecciso, Mariangela; Ocadlikova, Darina; Sangaletti, Sabina; Trabanelli, Sara; De Marchi, Elena; Orioli, Elisa; Pegoraro, Anna; Portararo, Paola; Jandus, Camilla; Bontadini, Andrea; Redavid, Annarita; Salvestrini, Valentina; Romero, Pedro; Colombo, Mario P; Di Virgilio, Francesco; Cavo, Michele; Adinolfi, Elena; Curti, Antonio

    2017-01-01

    Chemotherapy-induced immunogenic cell death can favor dendritic cell (DC) cross-priming of tumor-associated antigens for T cell activation thanks to the release of damage-associated molecular patterns, including ATP. Here, we tested the hypothesis that in acute myeloid leukemia (AML), ATP release, along with its well-known immune stimulatory effect, may also contribute to the generation of an immune suppressive microenvironment. In a cohort of AML patients, undergoing combined daunorubicin and cytarabine chemotherapy, a population of T regulatory cells (Tregs) with suppressive phenotype, expressing the immune checkpoint programmed cell death protein 1 (PD-1), was significantly increased. Moving from these results, initial in vitro data showed that daunorubicin was more effective than cytarabine in modulating DC function toward Tregs induction and such difference was correlated with the higher capacity of daunorubicin to induce ATP release from treated AML cells. DCs cultured with daunorubicin-treated AML cells upregulated indoleamine 2,3-dioxygenase 1 (IDO1), which induced anti-leukemia Tregs. These data were confirmed in vivo as daunorubicin-treated mice show an increase in extracellular ATP levels with increased number of Tregs, expressing PD-1 and IDO1 + CD39 + DCs. Notably, daunorubicin failed to induce Tregs and tolerogenic DCs in mice lacking the ATP receptor P2X7. Our data indicate that ATP release from chemotherapy-treated dying cells contributes to create an immune suppressive microenvironment in AML.

  7. ATP Release from Chemotherapy-Treated Dying Leukemia Cells Elicits an Immune Suppressive Effect by Increasing Regulatory T Cells and Tolerogenic Dendritic Cells

    Directory of Open Access Journals (Sweden)

    Mariangela Lecciso

    2017-12-01

    Full Text Available Chemotherapy-induced immunogenic cell death can favor dendritic cell (DC cross-priming of tumor-associated antigens for T cell activation thanks to the release of damage-associated molecular patterns, including ATP. Here, we tested the hypothesis that in acute myeloid leukemia (AML, ATP release, along with its well-known immune stimulatory effect, may also contribute to the generation of an immune suppressive microenvironment. In a cohort of AML patients, undergoing combined daunorubicin and cytarabine chemotherapy, a population of T regulatory cells (Tregs with suppressive phenotype, expressing the immune checkpoint programmed cell death protein 1 (PD-1, was significantly increased. Moving from these results, initial in vitro data showed that daunorubicin was more effective than cytarabine in modulating DC function toward Tregs induction and such difference was correlated with the higher capacity of daunorubicin to induce ATP release from treated AML cells. DCs cultured with daunorubicin-treated AML cells upregulated indoleamine 2,3-dioxygenase 1 (IDO1, which induced anti-leukemia Tregs. These data were confirmed in vivo as daunorubicin-treated mice show an increase in extracellular ATP levels with increased number of Tregs, expressing PD-1 and IDO1+CD39+ DCs. Notably, daunorubicin failed to induce Tregs and tolerogenic DCs in mice lacking the ATP receptor P2X7. Our data indicate that ATP release from chemotherapy-treated dying cells contributes to create an immune suppressive microenvironment in AML.

  8. Inhibition of Allograft Inflammatory Factor-1 in Dendritic Cells Restrains CD4+ T Cell Effector Responses and Induces CD25+Foxp3+ T Regulatory Subsets

    Directory of Open Access Journals (Sweden)

    Diana M. Elizondo

    2017-11-01

    Full Text Available Allograft inflammatory factor-1 (AIF1 is a cytoplasmic scaffold protein shown to influence immune responses in macrophages and microglial cells. The protein contains Ca2+ binding EF-hand and PDZ interaction domains important for mediating intracellular signaling complexes. This study now reports that AIF1 is expressed in CD11c+ dendritic cells (DC and silencing of expression restrains induction of antigen-specific CD4+ T cell effector responses. AIF1 knockdown in murine DC resulted in impaired T cell proliferation and skewed polarization away from T helper type 1 and 17 fates. In turn, there was a parallel expansion of IL-10-producing and CD25+Foxp3+ T regulatory subsets. These studies are the first to demonstrate that AIF1 expression in DC serves as a potent governor of cognate T cell responses and presents a novel target for engineering tolerogenic DC-based immunotherapies.

  9. Aspergillus fumigatus Cell Wall α-(1,3)-Glucan Stimulates Regulatory T-Cell Polarization by Inducing PD-L1 Expression on Human Dendritic Cells.

    Science.gov (United States)

    Stephen-Victor, Emmanuel; Karnam, Anupama; Fontaine, Thierry; Beauvais, Anne; Das, Mrinmoy; Hegde, Pushpa; Prakhar, Praveen; Holla, Sahana; Balaji, Kithiganahalli N; Kaveri, Srini V; Latgé, Jean-Paul; Aimanianda, Vishukumar; Bayry, Jagadeesh

    2017-12-05

    Human dendritic cell (DC) response to α-(1,3)-glucan polysaccharide of Aspergillus fumigatus and ensuing CD4+ T-cell polarization are poorly characterized. α-(1,3)-Glucan was isolated from A. fumigatus conidia and mycelia cell wall. For the analysis of polarization, DCs and autologous naive CD4+ T cells were cocultured. Phenotype of immune cells was analyzed by flow cytometry, and cytokines by enzyme-linked immunosorbent assay (ELISA). Blocking antibodies were used to dissect the role of Toll-like receptor 2 (TLR2) and programmed death-ligand 1 (PD-L1) in regulating α-(1,3)-glucan-mediated DC activation and T-cell responses. DCs from TLR2-deficient mice were additionally used to consolidate the findings. α-(1,3)-Glucan induced the maturation of DCs and was dependent in part on TLR2. "α-(1,3)-Glucan-educated" DCs stimulated the activation of naive T cells and polarized a subset of these cells into CD4+CD25+FoxP3+ regulatory T cells (Tregs). Mechanistically, Treg stimulation by α-(1,3)-glucan was dependent on the PD-L1 pathway that negatively regulated interferon-gamma (IFN-γ) secretion. Short α-(1,3)-oligosaccharides lacked the capacity to induce maturation of DCs but significantly blocked α-(1,3)-glucan-induced Treg polarization. PD-L1 dictates the balance between Treg and IFN-γ responses induced by α-(1,3)-glucan. Our data provide a rationale for the exploitation of immunotherapeutic approaches that target PD-1-PD-L1 to enhance protective immune responses to A. fumigatus infections. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  10. Secretory IgA in complex with Lactobacillus rhamnosus potentiates mucosal dendritic cell-mediated Treg cell differentiation via TLR regulatory proteins, RALDH2 and secretion of IL-10 and TGF-β.

    Science.gov (United States)

    Mikulic, Josip; Longet, Stéphanie; Favre, Laurent; Benyacoub, Jalil; Corthesy, Blaise

    2017-06-01

    The importance of secretory IgA in controlling the microbiota is well known, yet how the antibody affects the perception of the commensals by the local immune system is still poorly defined. We have previously shown that the transport of secretory IgA in complex with bacteria across intestinal microfold cells results in an association with dendritic cells in Peyer's patches. However, the consequences of such an interaction on dendritic cell conditioning have not been elucidated. In this study, we analyzed the impact of the commensal Lactobacillus rhamnosus, alone or associated with secretory IgA, on the responsiveness of dendritic cells freshly recovered from mouse Peyer's patches, mesenteric lymph nodes, and spleen. Lactobacillus rhamnosus-conditioned mucosal dendritic cells are characterized by increased expression of Toll-like receptor regulatory proteins [including single immunoglobulin interleukin-1 receptor-related molecule, suppressor of cytokine signaling 1, and Toll-interacting molecule] and retinaldehyde dehydrogenase 2, low surface expression of co-stimulatory markers, high anti- versus pro-inflammatory cytokine production ratios, and induction of T regulatory cells with suppressive function. Association with secretory IgA enhanced the anti-inflammatory/regulatory Lactobacillus rhamnosus-induced conditioning of mucosal dendritic cells, particularly in Peyer's patches. At the systemic level, activation of splenic dendritic cells exposed to Lactobacillus rhamnosus was partially dampened upon association with secretory IgA. These data suggest that secretory IgA, through coating of commensal bacteria, contributes to the conditioning of mucosal dendritic cells toward tolerogenic profiles essential for the maintenance of intestinal homeostasis.

  11. Induction of regulatory dendritic cells by dexamethasone and 1alpha,25-Dihydroxyvitamin D(3)

    DEFF Research Database (Denmark)

    Pedersen, Anders Elm; Gad, Monika; Walter, Mark R

    2004-01-01

    D(3) the active form of Vitamin D(3) (D(3)) in combination with dexamethasone (Dex) has a synergistic effect on LPS-induced maturation of DC. Monocyte-derived DCs cultured with D(3) and Dex during LPS-induced maturation have a low stimulatory effect on allogeneic T cells comparable...

  12. Defective IL-10 signaling in hyper-IgE syndrome results in impaired generation of tolerogenic dendritic cells and induced regulatory T cells

    Science.gov (United States)

    Saito, Masako; Nagasawa, Masayuki; Takada, Hidetoshi; Hara, Toshiro; Tsuchiya, Shigeru; Agematsu, Kazunaga; Yamada, Masafumi; Kawamura, Nobuaki; Ariga, Tadashi; Tsuge, Ikuya; Nonoyama, Shigeaki; Karasuyama, Hajime

    2011-01-01

    Hyper-IgE syndrome (HIES) is a primary immunodeficiency characterized by recurrent staphylococcal infections and atopic dermatitis associated with elevated serum IgE levels. Although defective differentiation of IL-17–producing CD4+ T cells (Th17) partly accounts for the susceptibility to staphylococcal skin abscesses and pneumonia, the pathogenesis of atopic manifestations in HIES still remains an enigma. In this study, we examined the differentiation and function of Th1, Th2, regulatory T cells (Treg cells), and dendritic cells (DCs) in HIES patients carrying either STAT3 or TYK2 mutations. Although the in vitro differentiation of Th1 and Th2 cells and the number and function of Treg cells in the peripheral blood were normal in HIES patients with STAT3 mutations, primary and monocyte-derived DCs showed defective responses to IL-10 and thus failed to become tolerogenic. When treated with IL-10, patient DCs showed impaired up-regulation of inhibitory molecules on their surface, including PD-L1 and ILT-4, compared with control DCs. Moreover, IL-10–treated DCs from patients displayed impaired ability to induce the differentiation of naive CD4+ T cells to FOXP3+ induced Treg cells (iTreg cells). These results suggest that the defective generation of IL-10–induced tolerogenic DCs and iTreg cells may contribute to inflammatory changes in HIES. PMID:21300911

  13. Novel vaccines targeting dendritic cells by coupling allergoids to nonoxidized mannan enhance allergen uptake and induce functional regulatorycells through programmed death ligand 1.

    Science.gov (United States)

    Sirvent, Sofía; Soria, Irene; Cirauqui, Cristina; Cases, Bárbara; Manzano, Ana I; Diez-Rivero, Carmen M; Reche, Pedro A; López-Relaño, Juan; Martínez-Naves, Eduardo; Cañada, F Javier; Jiménez-Barbero, Jesús; Subiza, Javier; Casanovas, Miguel; Fernández-Caldas, Enrique; Subiza, José Luis; Palomares, Oscar

    2016-08-01

    Allergen immunotherapy (AIT) is the only curative treatment for allergy. AIT faces pitfalls related to efficacy, security, duration, and patient compliance. Novel vaccines overcoming such inconveniences are in demand. We sought to study the immunologic mechanisms of action for novel vaccines targeting dendritic cells (DCs) generated by coupling glutaraldehyde-polymerized grass pollen allergoids to nonoxidized mannan (PM) compared with glutaraldehyde-polymerized allergoids (P) or native grass pollen extracts (N). Skin prick tests and basophil activation tests with N, P, or PM were performed in patients with grass pollen allergy. IgE-blocking experiments, flow cytometry, confocal microscopy, cocultures, suppression assays, real-time quantitative PCR, ELISAs, and ELISpot assays were performed to assess allergen capture by human DCs and T-cell responses. BALB/c mice were immunized with PM, N, or P. Antibody levels, cytokine production by splenocytes, and splenic forkhead box P3 (FOXP3)(+) regulatory T (Treg) cells were quantified. Experiments with oxidized PM were also performed. PM displays in vivo hypoallergenicity, induces potent blocking antibodies, and is captured by human DCs much more efficiently than N or P by mechanisms depending on mannose receptor- and dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin-mediated internalization. PM endorses human DCs to generate functional FOXP3(+) Treg cells through programmed death ligand 1. Immunization of mice with PM induces a shift to nonallergic responses and increases the frequency of splenic FOXP3(+) Treg cells. Mild oxidation impairs these effects in human subjects and mice, demonstrating the essential role of preserving the carbohydrate structure of mannan. Allergoids conjugated to nonoxidized mannan represent suitable vaccines for AIT. Our findings might also be of the utmost relevance to development of therapeutic interventions in other immune tolerance-related diseases. Copyright

  14. Trichomonas vaginalis α-Actinin 2 Modulates Host Immune Responses by Inducing Tolerogenic Dendritic Cells via IL-10 Production from Regulatory T Cells.

    Science.gov (United States)

    Lee, Hye-Yeon; Kim, Juri; Ryu, Jae-Sook; Park, Soon-Jung

    2017-08-01

    Trichomonas vaginalis is a pathogen that triggers severe immune responses in hosts. T. vaginalis α-actinin 2, Tvα-actinin 2, has been used to diagnose trichomoniasis. This study was undertaken to examine the role of Tvα-actinin 2 as an antigenic molecule to induce immune responses from humans. Western blot analysis using anti-Tvα-actinin 2 antibodies indicated its presence in the secreted proteins of T. vaginalis. ELISA was employed to measure cytokine production by vaginal epithelial cells, prostate cells, mouse dendritic cells (DCs), or T cells stimulated with T. vaginalis or Tvα-actinin 2 protein. Both T. vaginalis and rTvα-actinin 2 induced cytokine production from epithelial cell lines, including IL-10. Moreover, CD4+CD25- regulatory T cells (Treg cells) incubated with rTvα-actinin 2-treated DCs produced high levels of IL-10. These data indicate that Tvα-actinin 2 modulates immune responses via IL-10 production by Treg cells.

  15. Resident CD141 (BDCA3)+ dendritic cells in human skin produce IL-10 and induce regulatory T cells that suppress skin inflammation.

    Science.gov (United States)

    Chu, Chung-Ching; Ali, Niwa; Karagiannis, Panagiotis; Di Meglio, Paola; Skowera, Ania; Napolitano, Luca; Barinaga, Guillermo; Grys, Katarzyna; Sharif-Paghaleh, Ehsan; Karagiannis, Sophia N; Peakman, Mark; Lombardi, Giovanna; Nestle, Frank O

    2012-05-07

    Human skin immune homeostasis, and its regulation by specialized subsets of tissue-residing immune sentinels, is poorly understood. In this study, we identify an immunoregulatory tissue-resident dendritic cell (DC) in the dermis of human skin that is characterized by surface expression of CD141, CD14, and constitutive IL-10 secretion (CD141(+) DDCs). CD141(+) DDCs possess lymph node migratory capacity, induce T cell hyporesponsiveness, cross-present self-antigens to autoreactive T cells, and induce potent regulatory T cells that inhibit skin inflammation. Vitamin D(3) (VitD3) promotes certain phenotypic and functional properties of tissue-resident CD141(+) DDCs from human blood DCs. These CD141(+) DDC-like cells can be generated in vitro and, once transferred in vivo, have the capacity to inhibit xeno-graft versus host disease and tumor alloimmunity. These findings suggest that CD141(+) DDCs play an essential role in the maintenance of skin homeostasis and in the regulation of both systemic and tumor alloimmunity. Finally, VitD3-induced CD141(+) DDC-like cells have potential clinical use for their capacity to induce immune tolerance.

  16. TGF-β of lung cancer microenvironment upregulates B7H1 and GITRL expression in dendritic cells and is associated with regulatory T cell generation.

    Science.gov (United States)

    Ni, Xiao Yan; Sui, Hua Xiu; Liu, Yao; Ke, Shi Zhong; Wang, Yi Nan; Gao, Feng Guang

    2012-08-01

    The effects of TGF-β on dendritic cells (DCs) on the tumor microenvironment are not well understood. We report, here, the establishment of an in vitro lung cancer microenvironment by co-incubation of seminaphtharhodafluor (SNARF) labeled Lewis lung cancer (LLC) cells, carboxyfluorescein succinimidyl ester (CFSE) labeled fibroblasts and 4-chloromethyl-7-hydroxycoumarin (CMHC) labeled DCs. Raw 264.7, EL4 and NCI-H446 cells were able to synthesize TGF-β which was determined by flow cyto-metry and western blotting, respectively. Furthermore, TGF-β efficiently increased regulatory T-cell (Treg) expansion and upregulated DC B7H1 and GITRL expression. TGF-β and the co-incubation of LLC cells, fibroblasts with DCs could augment the expression of B7H1 and GITRL molecules of DCs. The data presented here indicate that the B7H1 and GITRL molecules may play an important role in TGF-β-induced Treg expansion of lung cancer microenvironment.

  17. Increase of circulating CD4+CD25highFoxp3+ regulatory T cells in patients with metastatic renal cell carcinoma during treatment with dendritic cell vaccination and low-dose interleukin-2

    DEFF Research Database (Denmark)

    Berntsen, Annika; Brimnes, Marie Klinge; thor Straten, Per

    2010-01-01

    Regulatory T cells (Treg) play an important role in the maintenance of immune tolerance and may be one of the obstacles of successful tumor immunotherapy. In this study, we analyzed the impact of administration of dendritic cell (DC) vaccination in combination with low-dose interleukin (IL)-2...... in patients with metastatic renal cell carcinoma on the frequency of CD4+CD25highFoxp3+ Treg cells in peripheral blood. We found that the treatment increased the frequency of Treg cells more than 7-fold compared with pretreatment levels (P...

  18. Donor-Derived Regulatory Dendritic Cell Infusion Maintains Donor-Reactive CD4+CTLA4hi T Cells in Non-Human Primate Renal Allograft Recipients Treated with CD28 Co-Stimulation Blockade

    OpenAIRE

    Mohamed B. Ezzelarab; Lien Lu; William F. Shufesky; Adrian E. Morelli; Adrian E. Morelli; Angus W. Thomson; Angus W. Thomson

    2018-01-01

    Donor-derived regulatory dendritic cell (DCreg) infusion before transplantation, significantly prolongs renal allograft survival in non-human primates. This is associated with enhanced expression of the immunoregulatory molecules cytotoxic T-lymphocyte-associated antigen (Ag) 4 (CTLA4) and programmed cell death protein 1 (PD1) by host donor-reactive T cells. In rodents and humans, CD28 co-stimulatory pathway blockade with the fusion protein CTLA4:Ig (CTLA4Ig) is associated with reduced differ...

  19. Bifidobacterium infantis Potentially Alleviates Shrimp Tropomyosin-Induced Allergy by Tolerogenic Dendritic Cell-Dependent Induction of Regulatory T Cells and Alterations in Gut Microbiota

    Directory of Open Access Journals (Sweden)

    Linglin Fu

    2017-11-01

    Full Text Available Shellfish is one of the major allergen sources worldwide, and tropomyosin (Tm is the predominant allergic protein in shellfish. Probiotics has been appreciated for its beneficial effects on the host, including anti-allergic and anti-inflammatory effects, although the underlying mechanisms were not fully understood. In this study, oral administration of probiotic strain Bifidobacterium infantis 14.518 (Binf effectively suppressed Tm-induced allergic response in a mouse model by both preventive and therapeutic strategies. Further results showed that Binf stimulated dendritic cells (DCs maturation and CD103+ tolerogenic DCs accumulation in gut-associated lymphoid tissue, which subsequently induced regulatory T cells differentiation for suppressing Th2-biased response. We also found that Binf regulates the alterations of gut microbiota composition. Specifically, the increase of Dorea and decrease of Ralstonia is highly correlated with Th2/Treg ratio and may contribute to alleviating Tm-induced allergic responses. Our findings provide molecular insight into the application of Binf in alleviating food allergy and even gut immune homeostasis.

  20. 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.

  1. Comparative analysis of a large panel of non-starch polysaccharides reveals structures with selective regulatory properties in dendritic cells

    DEFF Research Database (Denmark)

    Wismar, René; Pedersen, Susanne Brix; Lærke, Helle Nygaard

    2011-01-01

    -regulate LPS-induced IL-12p70 production. The most potent NSP induced up-regulation of CD86 on DC independently of LPS stimulation. Cereal-based β-glucans showed less potency than β-glucans of microbial origin, but proper molecular weight composition and preparation may improve effectiveness......Scope: Structural-based recognition of foreign molecules is essential for activation of dendritic cells (DCs) that play a key role in regulation of gut mucosal immunity. Orally ingested non-starch polysaccharides (NSP) are ascribed many health-promoting properties, but currently we lack insight...... into the impact of structure and size for their capacity to affect immune responses.Methods and results: This study addresses the importance of chemical structure, size, origin and presence of contaminants for the capacity of both dietary and non-food NSP to modulate DC. Of 28 NSP products, β-glucans of microbial...

  2. Low-dose temozolomide before dendritic-cell vaccination reduces (specifically) CD4+CD25++Foxp3+ regulatory T-cells in advanced melanoma patients.

    Science.gov (United States)

    Ridolfi, Laura; Petrini, Massimiliano; Granato, Anna Maria; Gentilcore, Giusy; Simeone, Ester; Ascierto, Paolo Antonio; Pancisi, Elena; Ancarani, Valentina; Fiammenghi, Laura; Guidoboni, Massimo; de Rosa, Francesco; Valmorri, Linda; Scarpi, Emanuela; Nicoletti, Stefania Vittoria Luisa; Baravelli, Stefano; Riccobon, Angela; Ridolfi, Ruggero

    2013-05-31

    In cancer immunotherapy, dendritic cells (DCs) play a fundamental role in the dialog between innate and adaptive immune response, but several immunosuppressive mechanisms remain to be overcome. For example, a high number of CD4+CD25++Foxp3+ regulatory T-cells (Foxp3+Tregs) have been observed in the peripheral blood and tumor microenvironment of cancer patients. On the basis of this, we conducted a study on DC-based vaccination in advanced melanoma, adding low-dose temozolomide to obtain lymphodepletion. Twenty-one patients were entered onto our vaccination protocol using autologous DCs pulsed with autologous tumor lysate and keyhole limpet hemocyanin. Patients received low-dose temozolomide before vaccination and 5 days of low-dose interleukin-2 (IL-2) after vaccination. Circulating Foxp3+Tregs were evaluated before and after temozolomide, and after IL-2. Among the 17 evaluable patients we observed 1 partial response (PR), 6 stable disease (SD) and 10 progressive disease (PD). The disease control rate (PR+SD = DCR) was 41% and median overall survival was 10 months. Temozolomide reduced circulating Foxp3+Treg cells in all patients. A statistically significant reduction of 60% was observed in Foxp3+Tregs after the first cycle, whereas the absolute lymphocyte count decreased by only 14%. Conversely, IL-2 increased Foxp3+Treg cell count by 75.4%. Of note the effect of this cytokine, albeit not statistically significant, on the DCR subgroup led to a further 33.8% reduction in Foxp3+Treg cells. Our results suggest that the combined immunological therapy, at least as far as the DCR subgroup is concerned, effectively reduced the number of Foxp3+Treg cells, which exerted a blunting effect on the growth-stimulating effect of IL-2. However, this regimen, with its current modality, would not seem to be capable of improving clinical outcome.

  3. Dendritic Cell-Specific Deletion of β-Catenin Results in Fewer Regulatory T-Cells without Exacerbating Autoimmune Collagen-Induced Arthritis.

    Science.gov (United States)

    Alves, C Henrique; Ober-Blöbaum, Julia L; Brouwers-Haspels, Inge; Asmawidjaja, Patrick S; Mus, Adriana M C; Razawy, Wida; Molendijk, Marlieke; Clausen, Björn E; Lubberts, Erik

    2015-01-01

    Dendritic cells (DCs) are professional antigen presenting cells that have the dual ability to stimulate immunity and maintain tolerance. However, the signalling pathways mediating tolerogenic DC function in vivo remain largely unknown. The β-catenin pathway has been suggested to promote a regulatory DC phenotype. The aim of this study was to unravel the role of β-catenin signalling to control DC function in the autoimmune collagen-induced arthritis model (CIA). Deletion of β-catenin specifically in DCs was achieved by crossing conditional knockout mice with a CD11c-Cre transgenic mouse line. Bone marrow-derived DCs (BMDCs) were generated and used to study the maturation profile of these cells in response to a TLR2 or TLR4 ligand stimulation. CIA was induced by intra-dermal immunization with 100 μg chicken type II collagen in complete Freund's adjuvant on days 0 and 21. CIA incidence and severity was monitored macroscopically and by histology. The T cell profile as well as their cytokine production were analysed by flow cytometry. Lack of β-catenin specifically in DCs did not affect the spontaneous, TLR2- or TLR4-induced maturation and activation of BMDCs or their cytokine production. Moreover, no effect on the incidence and severity of CIA was observed in mice lacking β-catenin in CD11c+ cells. A decreased frequency of splenic CD3+CD8+ T cells and of regulatory T cells (Tregs) (CD4+CD25highFoxP3+), but no changes in the frequency of splenic Th17 (CCR6+CXCR3-CCR4+), Th2 (CCR6-CXCR3-CCR4+) and Th1 (CCR6-CXCR3+CCR4-) cells were observed in these mice under CIA condition. Furthermore, the expression of IL-17A, IL-17F, IL-22, IL-4 or IFNγ was also not affected. Our data indicate that ablation of β-catenin expression in DCs did not alter the course and severity of CIA. We conclude that although deletion of β-catenin resulted in a lower frequency of Tregs, this decrease was not sufficient to aggravate the onset and severity of CIA.

  4. Dendritic Cell-Specific Deletion of β-Catenin Results in Fewer Regulatory T-Cells without Exacerbating Autoimmune Collagen-Induced Arthritis.

    Directory of Open Access Journals (Sweden)

    C Henrique Alves

    Full Text Available Dendritic cells (DCs are professional antigen presenting cells that have the dual ability to stimulate immunity and maintain tolerance. However, the signalling pathways mediating tolerogenic DC function in vivo remain largely unknown. The β-catenin pathway has been suggested to promote a regulatory DC phenotype. The aim of this study was to unravel the role of β-catenin signalling to control DC function in the autoimmune collagen-induced arthritis model (CIA. Deletion of β-catenin specifically in DCs was achieved by crossing conditional knockout mice with a CD11c-Cre transgenic mouse line. Bone marrow-derived DCs (BMDCs were generated and used to study the maturation profile of these cells in response to a TLR2 or TLR4 ligand stimulation. CIA was induced by intra-dermal immunization with 100 μg chicken type II collagen in complete Freund's adjuvant on days 0 and 21. CIA incidence and severity was monitored macroscopically and by histology. The T cell profile as well as their cytokine production were analysed by flow cytometry. Lack of β-catenin specifically in DCs did not affect the spontaneous, TLR2- or TLR4-induced maturation and activation of BMDCs or their cytokine production. Moreover, no effect on the incidence and severity of CIA was observed in mice lacking β-catenin in CD11c+ cells. A decreased frequency of splenic CD3+CD8+ T cells and of regulatory T cells (Tregs (CD4+CD25highFoxP3+, but no changes in the frequency of splenic Th17 (CCR6+CXCR3-CCR4+, Th2 (CCR6-CXCR3-CCR4+ and Th1 (CCR6-CXCR3+CCR4- cells were observed in these mice under CIA condition. Furthermore, the expression of IL-17A, IL-17F, IL-22, IL-4 or IFNγ was also not affected. Our data indicate that ablation of β-catenin expression in DCs did not alter the course and severity of CIA. We conclude that although deletion of β-catenin resulted in a lower frequency of Tregs, this decrease was not sufficient to aggravate the onset and severity of CIA.

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

    International Nuclear Information System (INIS)

    Jeong, Young-Il; Kim, Seung Hyun; Ju, Jung Won; Cho, Shin Hyeong; Lee, Won Ja; Park, Jin Wook; Park, Yeong-Min; Lee, Sang Eun

    2011-01-01

    Highlights: → Treatment with Clonorchis sinensis-derived total protein attenuates OVA-induced airway inflammation and AHR to methacholine. → Induction of CD4 + CD25 + Foxp3 + T cells and IL-10 along with suppression of splenocyte proliferation by C. sinensis-derived total protein. → 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 + CD25 + Foxp3 + 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 relationship between the allergic immune

  6. Dendritic cell-specific deletion of β-catenin results in fewer regulatory T-cells without exacerbating autoimmune collagen-induced arthritis

    NARCIS (Netherlands)

    C.H. Alves (Celso Henrique); J.L. Ober-Blöbaum (Julia); I. Brouwers-Haspels (Inge); P. Asmawidjaja (Patrick); A.M.C. Mus (Adriana); W. Razawy (Wida); M. Molendijk (Marlieke); B.E. Clausen (Bjorn); E.W. Lubberts (Erik)

    2015-01-01

    textabstractDendritic cells (DCs) are professional antigen presenting cells that have the dual ability to stimulate immunity and maintain tolerance. However, the signalling pathways mediating tolerogenic DC function in vivo remain largely unknown. The β-catenin pathway has been suggested to promote

  7. Low doses of cholera toxin and its mediator cAMP induce CTLA-2 secretion by dendritic cells to enhance regulatory T cell conversion.

    Directory of Open Access Journals (Sweden)

    Cinthia Silva-Vilches

    Full Text Available Immature or semi-mature dendritic cells (DCs represent tolerogenic maturation stages that can convert naive T cells into Foxp3+ induced regulatory T cells (iTreg. Here we found that murine bone marrow-derived DCs (BM-DCs treated with cholera toxin (CT matured by up-regulating MHC-II and costimulatory molecules using either high or low doses of CT (CThi, CTlo or with cAMP, a known mediator CT signals. However, all three conditions also induced mRNA of both isoforms of the tolerogenic molecule cytotoxic T lymphocyte antigen 2 (CTLA-2α and CTLA-2β. Only DCs matured under CThi conditions secreted IL-1β, IL-6 and IL-23 leading to the instruction of Th17 cell polarization. In contrast, CTlo- or cAMP-DCs resembled semi-mature DCs and enhanced TGF-β-dependent Foxp3+ iTreg conversion. iTreg conversion could be reduced using siRNA blocking of CTLA-2 and reversely, addition of recombinant CTLA-2α increased iTreg conversion in vitro. Injection of CTlo- or cAMP-DCs exerted MOG peptide-specific protective effects in experimental autoimmune encephalomyelitis (EAE by inducing Foxp3+ Tregs and reducing Th17 responses. Together, we identified CTLA-2 production by DCs as a novel tolerogenic mediator of TGF-β-mediated iTreg induction in vitro and in vivo. The CT-induced and cAMP-mediated up-regulation of CTLA-2 also may point to a novel immune evasion mechanism of Vibrio cholerae.

  8. RelB+ Steady-State Migratory Dendritic Cells Control the Peripheral Pool of the Natural Foxp3+ Regulatory T Cells

    Directory of Open Access Journals (Sweden)

    Anja Döhler

    2017-06-01

    Full Text Available Thymus-derived natural Foxp3+ CD4+ regulatory T cells (nTregs play a key role in maintaining immune tolerance and preventing autoimmune disease. Several studies indicate that dendritic cells (DCs are critically involved in the maintenance and proliferation of nTregs. However, the mechanisms how DCs manage to keep the peripheral pool at constant levels remain poorly understood. Here, we describe that the NF-κB/Rel family transcription factor RelB controls the frequencies of steady-state migratory DCs (ssmDCs in peripheral lymph nodes and their numbers control peripheral nTreg homeostasis. DC-specific RelB depletion was investigated in CD11c-Cre × RelBfl/fl mice (RelBDCko, which showed normal frequencies of resident DCs in lymph nodes and spleen while the subsets of CD103− Langerin− dermal DCs (dDCs and Langerhans cells but not CD103+ Langerin+ dDC of the ssmDCs in skin-draining lymph nodes were increased. Enhanced frequencies and proliferation rates were also observed for nTregs and a small population of CD4+ CD44high CD25low memory-like T cells (Tml. Interestingly, only the Tml but not DCs showed an increase in IL-2-producing capacity in lymph nodes of RelBDCko mice. Blocking of IL-2 in vivo reduced the frequency of nTregs but increased the Tml frequencies, followed by a recovery of nTregs. Taken together, by employing RelBDCko mice with increased frequencies of ssmDCs our data indicate a critical role for specific ssmDC subsets for the peripheral nTreg and IL-2+ Tml frequencies during homeostasis.

  9. Increase of Circulating CD4(+)CD25(high)Foxp3(+) Regulatory T Cells in Patients With Metastatic Renal Cell Carcinoma During Treatment With Dendritic Cell Vaccination and Low-Dose Interleukin-2

    DEFF Research Database (Denmark)

    Berntsen, Annika; Brimnes, M.K.; Straten, P.T.

    2010-01-01

    Regulatory T cells (Treg) play an important role in the maintenance of immune tolerance and may be one of the obstacles of successful tumor immunotherapy. In this study, we analyzed the impact of administration of dendritic cell (DC) vaccination in combination with low-dose interleukin (IL)-2...... in patients with metastatic renal cell carcinoma on the frequency of CD4(+) CD25(high)Foxp3(+) Treg cells in peripheral blood. We found that the treatment increased the frequency of Treg cells more than 7-fold compared with pretreatment levels (P cells decreased when patients...... had been off IL-2 treatment for only 8 days, but remained higher than pretreatment levels. A functional assay showed that isolated Treg cells were capable of inhibiting proliferation of responder cells. Also, in vitro studies showed that coculture of mature DCs, autologous T cells and IL-2 leads...

  10. Evaluation of monocyte-derived dendritic cells, T regulatory and Th17 cells in chronic myeloid leukemia patients treated with tyrosine kinase inhibitors.

    Science.gov (United States)

    Hus, Iwona; Tabarkiewicz, Jacek; Lewandowska, Magdalena; Wasiak, Magdalena; Wdowiak, Paulina; Kusz, Maria; Legieć, Monika; Dmoszyńska, Anna; Roliński, Jacek

    2011-01-01

    Immunotherapy with dendritic cells (DC) may constitute a new and advantageous option for patients with chronic myeloid leukemia (CML) who respond to therapy with tyrosine kinase inhibitors (TKI), but do not reach complete cytogenetic or molecular remission. In this study, we evaluated the immunophenotype of DC generated from monocytes (Mo-DC) of patients with CML and the influence of TKI therapy on the results of CML-DC generation. We also measured the percentages of T regulatory cells (Tregs) as well as Th17 cells in 19 untreated patients suffering from CML, and in 28 CML patients treated with TKI. We found that DC can be reliably generated from the peripheral blood CD14+ cells of untreated CML patients. But we observed a persistent expression of CD14 monocyte marker on DC from CML patients, together with lower percentages of Mo-DC with expression of CD1a (p = 0.002), CD80 (p = 0.0005), CD83 (p = 0.0004), and CD209 (p = 0.02) compared to healthy donors. There was an adverse correlation between WBC count and the percentage of Mo-DC with co-expression of CD80 and CD86 (R = -0.63; p = 0.03). In patients treated with TKI, we observed higher efficacy of DC generation in seven-day cultures, compared to untreated patients. Expression of CD209 on DC was higher in patients treated with TKI (0.02). The duration of TKI therapy correlated adversely with MFI for CD1a (R = -0.49; p = 0.006) and positively with MFI for CD83 (R = 0.63; p = 0.01). Percentages of CD4+CD25highFoxP3+ cells (p = 0.0002) and Th17 cells (p = 0.02) were significantly higher in untreated CML patients compared to healthy controls. There was a significant correlation between the percentage of Treg cells and the percentage of peripheral blood basophiles (R = 0.821; p = 0.02). There were no changes in Tregs or Th17 cell percentages in CML patients after six months of TKI therapy. However, the expression of intracellular IL-17 in Th17 cells correlated negatively with the time of TKI therapy in the whole group

  11. Evaluation of monocyte-derived dendritic cells, T regulatory and Th17 cells in chronic myeloid leukemia patients treated with tyrosine kinase inhibitors

    Directory of Open Access Journals (Sweden)

    Jacek Roliński

    2011-04-01

    Full Text Available Immunotherapy with dendritic cells (DC may constitute a new and advantageous option for patients with chronic myeloid leukemia (CML who respond to therapy with tyrosine kinase inhibitors (TKI, but do not reach complete cytogenetic or molecular remission. In this study, we evaluated the immunophenotype of DC generated from monocytes (Mo-DC of patients with CML and the influence of TKI therapy on the results of CML-DC generation. We also measured the percentages of T regulatory cells (Tregs as well as Th17 cells in 19 untreated patients suffering from CML, and in 28 CML patients treated with TKI. We found that DC can be reliably generated from the peripheral blood CD14+ cells of untreated CML patients. But we observed a persistent expression of CD14 monocyte marker on DC from CML patients, together with lower percentages of Mo-DC with expression of CD1a (p = 0.002, CD80 (p = 0.0005, CD83 (p = 0.0004, and CD209 (p = 0.02 compared to healthy donors. There was an adverse correlation between WBC count and the percentage of Mo-DC with co-expression of CD80 and CD86 (R = –0.63; p = 0.03. In patients treated with TKI, we observed higher efficacy of DC generation in seven-day cultures, compared to untreated patients. Expression of CD209 on DC was higher in patients treated with TKI (0.02. The duration of TKI therapy correlated adversely with MFI for CD1a (R = –0.49; p = 0.006 and positively with MFI for CD83 (R = 0.63; p = 0.01. Percentages of CD4+CD25highFoxP3+ cells (p = 0.0002 and Th17 cells (p = 0.02 were significantly higher in untreated CML patients compared to healthy controls. There was a significant correlation between the percentage of Treg cells and the percentage of peripheral blood basophiles (R = 0.821; p = 0.02. There were no changes in Tregs or Th17 cell percentages in CML patients after six months of TKI therapy. However, the expression of intracellular IL-17 in Th17 cells correlated negatively with the time of TKI therapy in the

  12. Neutrophils, dendritic cells and Toxoplasma.

    Science.gov (United States)

    Denkers, Eric Y; Butcher, Barbara A; Del Rio, Laura; Bennouna, Soumaya

    2004-03-09

    Toxoplasma gondii rapidly elicits strong Type 1 cytokine-based immunity. The necessity for this response is well illustrated by the example of IFN-gamma and IL-12 gene knockout mice that rapidly succumb to the effects of acute infection. The parasite itself is skilled at sparking complex interactions in the innate immune system that lead to protective immunity. Neutrophils are one of the first cell types to arrive at the site of infection, and the cells release several proinflammatory cytokines and chemokines in response to Toxoplasma. Dendritic cells are an important source of IL-12 during infection with T. gondii and other microbial pathogens, and they are also specialized for high-level antigen presentation to T lymphocytes. Tachyzoites express at least two types of molecules that trigger innate immune cell cytokine production. One of these involves Toll-like receptor/MyD88 pathways common to many microbial pathogens. The second pathway is less conventional and involves molecular mimicry between a parasite cyclophilin and host CC chemokine receptor 5-binding ligands. Neutrophils, dendritic cells and Toxoplasma work together to elicit the immune response required for host survival. Cytokine and chemokine cross-talk between parasite-triggered neutrophils and dendritic cells results in recruitment, maturation and activation of the latter. Neutrophil-empowered dendritic cells possess properties expected of highly potent antigen presenting cells that drive T helper 1 generation.

  13. 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

  14. Divergent Effects of Dendritic Cells on Pancreatitis

    Science.gov (United States)

    2015-09-01

    role of dendritic cells in pancreatitis. Dendritic cells are professional antigen presenting cells which initiate innate and adaptive immune... Lymphoid -tissue-specific homing of bone- marrow-derived dendritic cells . Blood. 113:6638–6647. http://dx.doi .org/10.1182/blood-2009-02-204321 Dapito...Award Number: W81XWH-12-1-0313 TITLE: Divergent Effects of Dendritic Cells on Pancreatitis PRINCIPAL INVESTIGATOR: Dr. George Miller

  15. Characterization of regulatory dendritic cells that mitigate acute graft-versus-host disease in older mice following allogeneic bone marrow transplantation.

    Science.gov (United States)

    Scroggins, Sabrina M; Olivier, Alicia K; Meyerholz, David K; Schlueter, Annette J

    2013-01-01

    Despite improvements in human leukocyte antigen matching and pharmacologic prophylaxis, acute graft-versus-host disease (GVHD) is often a fatal complication following hematopoietic stem cell transplant (HSCT). Older HSCT recipients experience significantly increased morbidity and mortality compared to young recipients. Prophylaxis with syngeneic regulatory dendritic cells (DCreg) in young bone marrow transplanted (BMT) mice has been shown to decrease GVHD-associated mortality. To evaluate this approach in older BMT recipients, young (3-4 months) and older (14-18 months) DCreg were generated using GM-CSF, IL-10, and TGFβ. Analysis of young versus older DCreg following culture revealed no differences in phenotype. The efficacy of DCreg treatment in older BMT mice was evaluated in a BALB/c→C57Bl/6 model of GVHD; on day 2 post-BMT (d +2), mice received syngeneic, age-matched DCreg. Although older DCreg-treated BMT mice showed decreased morbidity and mortality compared to untreated BMT mice (all of which died), there was a small but significant decrease in the survival of older DCreg-treated BMT mice (75% survival) compared to young DCreg-treated BMT mice (90% survival). To investigate differences between dendritic cells (DC) in young and older DCreg-treated BMT mice that may play a role in DCreg function in vivo, DC phenotypes were assessed following DCreg adoptive transfer. Transferred DCreg identified in older DCreg-treated BMT mice at d +3 showed significantly lower expression of PD-L1 and PIR B compared to DCreg from young DCreg-treated BMT mice. In addition, donor DC identified in d +21 DCreg-treated BMT mice displayed increased inhibitory molecule and decreased co-stimulatory molecule expression compared to d +3, suggesting induction of a regulatory phenotype on the donor DC. In conclusion, these data indicate DCreg treatment is effective in the modulation of GVHD in older BMT recipients and provide evidence for inhibitory pathways that DCreg and donor DC may

  16. Characterization of regulatory dendritic cells that mitigate acute graft-versus-host disease in older mice following allogeneic bone marrow transplantation.

    Directory of Open Access Journals (Sweden)

    Sabrina M Scroggins

    Full Text Available Despite improvements in human leukocyte antigen matching and pharmacologic prophylaxis, acute graft-versus-host disease (GVHD is often a fatal complication following hematopoietic stem cell transplant (HSCT. Older HSCT recipients experience significantly increased morbidity and mortality compared to young recipients. Prophylaxis with syngeneic regulatory dendritic cells (DCreg in young bone marrow transplanted (BMT mice has been shown to decrease GVHD-associated mortality. To evaluate this approach in older BMT recipients, young (3-4 months and older (14-18 months DCreg were generated using GM-CSF, IL-10, and TGFβ. Analysis of young versus older DCreg following culture revealed no differences in phenotype. The efficacy of DCreg treatment in older BMT mice was evaluated in a BALB/c→C57Bl/6 model of GVHD; on day 2 post-BMT (d +2, mice received syngeneic, age-matched DCreg. Although older DCreg-treated BMT mice showed decreased morbidity and mortality compared to untreated BMT mice (all of which died, there was a small but significant decrease in the survival of older DCreg-treated BMT mice (75% survival compared to young DCreg-treated BMT mice (90% survival. To investigate differences between dendritic cells (DC in young and older DCreg-treated BMT mice that may play a role in DCreg function in vivo, DC phenotypes were assessed following DCreg adoptive transfer. Transferred DCreg identified in older DCreg-treated BMT mice at d +3 showed significantly lower expression of PD-L1 and PIR B compared to DCreg from young DCreg-treated BMT mice. In addition, donor DC identified in d +21 DCreg-treated BMT mice displayed increased inhibitory molecule and decreased co-stimulatory molecule expression compared to d +3, suggesting induction of a regulatory phenotype on the donor DC. In conclusion, these data indicate DCreg treatment is effective in the modulation of GVHD in older BMT recipients and provide evidence for inhibitory pathways that DCreg and

  17. Tolerogenic dendritic cells from poorly compensated type 1 diabetes patients have decreased ability to induce stable antigen-specific T cell hyporesponsiveness and generation of suppressive regulatory T cells

    DEFF Research Database (Denmark)

    Dánova, Klara; Grohova, Anna; Strnadova, Pavla

    2017-01-01

    state of patients. tolDCs differentiated from both groups of patients acquired a regulatory phenotype and an anti-inflammatory profile. Interestingly, tolDCs from well-controlled patients expressed higher levels of inhibitory molecules IL-T3 and PD-L1. Additionally, glutamic acid decarboxylase (GAD)65......Tolerogenic dendritic cells (tolDCs) may offer an interesting intervention strategy to re-establish Ag-specific tolerance in autoimmune diseases, including type 1 diabetes (T1D). T1D results from selective destruction of insulin-producing b cells leading to hyperglycemia that, in turn, specifically...... suppressive abilities. The functionality of tolDCs was confirmed in the adoptive transfer model of NOD-SCID mice where tolDCs delayed diabetes onset. These results suggest that metabolic control of T1D affects the functional characteristics of tolDCs and subsequent effector T cell responses. Metabolic control...

  18. High PD-L1/CD86 MFI ratio and IL-10 secretion characterize human regulatory dendritic cells generated for clinical testing in organ transplantation.

    Science.gov (United States)

    Zahorchak, Alan F; Macedo, Camila; Hamm, David E; Butterfield, Lisa H; Metes, Diana M; Thomson, Angus W

    2018-01-01

    Human regulatory dendritic cells (DCreg) were generated from CD14 immunobead-purified or elutriated monocytes in the presence of vitamin D3 and IL-10. They exhibited similar, low levels of costimulatory CD80 and CD86, but comparatively high levels of co-inhibitory programed death ligand-1 (PD-L1) and IL-10 production compared to control immature DC (iDC). Following Toll-like receptor 4 ligation, unlike control iDC, DCreg resisted phenotypic and functional maturation and further upregulated PD-L1:CD86 expression. Whereas LPS-stimulated control iDC (mature DC; matDC) secreted pro-inflammatory tumor necrosis factor but no IL-10, the converse was observed for LPS-stimulated DCreg. DCreg weakly stimulated naïve and memory allogeneic CD4 + and CD8 + T cell proliferation and IFNγ, IL-17A and perforin/granzyme B production in MLR. Their stimulatory function was enhanced however, by blocking PD-1 ligation. High-throughput T cell receptor (TCR) sequencing revealed that, among circulating T cell subsets, memory CD8 + T cells contained the most alloreactive TCR clonotypes and that, while matDC expanded these alloreactive memory CD8 TCR clonotypes, DCreg induced more attenuated responses. These findings demonstrate the feasibility of generating highly-purified GMP-grade DCreg for systemic infusion, their influence on the alloreactive T cell response, and a key mechanistic role of the PD1 pathway. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Donor-Derived Regulatory Dendritic Cell Infusion Maintains Donor-Reactive CD4+CTLA4hi T Cells in Non-Human Primate Renal Allograft Recipients Treated with CD28 Co-Stimulation Blockade.

    Science.gov (United States)

    Ezzelarab, Mohamed B; Lu, Lien; Shufesky, William F; Morelli, Adrian E; Thomson, Angus W

    2018-01-01

    Donor-derived regulatory dendritic cell (DCreg) infusion before transplantation, significantly prolongs renal allograft survival in non-human primates. This is associated with enhanced expression of the immunoregulatory molecules cytotoxic T-lymphocyte-associated antigen (Ag) 4 (CTLA4) and programmed cell death protein 1 (PD1) by host donor-reactive T cells. In rodents and humans, CD28 co-stimulatory pathway blockade with the fusion protein CTLA4:Ig (CTLA4Ig) is associated with reduced differentiation and development of regulatory T cells (Treg). We hypothesized that upregulation of CTLA4 by donor-reactive CD4 + T cells in DCreg-infused recipients treated with CTLA4Ig, might be associated with higher incidences of donor-reactive CD4 + T cells with a Treg phenotype. In normal rhesus monkeys, allo-stimulated CD4 + CTLA4 hi , but not CD4 + CTLA4 med/lo T cells exhibited a regulatory phenotype, irrespective of PD1 expression. CTLA4Ig significantly reduced the incidence of CD4 + CTLA4 hi , but not CD4 + CTLA4 med/lo T cells following allo-stimulation, associated with a significant reduction in the CD4 + CTLA4 hi /CD4 + CTLA4 med/lo T cell ratio. In CTLA4Ig-treated renal allograft recipient monkeys, there was a marked reduction in circulating donor-reactive CD4 + CTLA4 hi T cells. In contrast, in CTLA4Ig-treated monkeys with DCreg infusion, no such reduction was observed. In parallel, the donor-reactive CD4 + CTLA4 hi /CD4 + CTLA4 med/lo T cell ratio was reduced significantly in graft recipients without DCreg infusion, but increased in those given DCreg. These observations suggest that pre-transplant DCreg infusion promotes and maintains donor-reactive CD4 + CTLA4 hi T cells with a regulatory phenotype after transplantation, even in the presence of CD28 co-stimulation blockade.

  20. 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.

  1. Immunity and Tolerance Induced by Intestinal Mucosal Dendritic Cells

    Directory of Open Access Journals (Sweden)

    Julio Aliberti

    2016-01-01

    Full Text Available 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 against pathogens. A potential result of unbalanced tolerogenic versus proinflammatory responses mediated by dendritic cells is associated with chronic inflammatory conditions, such as Crohn’s disease, ulcerative colitis, food allergies, and celiac disease. Herein, we review the dendritic cell population involved in mediating tolerance and immunity in mucosal surfaces, the progress in unveiling their development in vivo, and factors that can influence their functions.

  2. Uptake of donor lymphocytes treated with 8-methoxypsoralen and ultraviolet A light by recipient dendritic cells induces CD4+CD25+Foxp3+ regulatory T cells and down-regulates cardiac allograft rejection

    International Nuclear Information System (INIS)

    Zheng, De-Hua; Dou, Li-Ping; Wei, Yu-Xiang; Du, Guo-Sheng; Zou, Yi-Ping; Song, Ji-Yong; Zhu, Zhi-Dong; Cai, Ming; Qian, Ye-Yong; Shi, Bing-Yi

    2010-01-01

    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-γ 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 + CD25 high Foxp3 + 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.

  3. 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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  4. Changes in markers associated with dendritic cells driving the differentiation of either TH2 cells or regulatory T cells correlate with clinical benefit during allergen immunotherapy.

    Science.gov (United States)

    Gueguen, Claire; Bouley, Julien; Moussu, Hélène; Luce, Sonia; Duchateau, Magalie; Chamot-Rooke, Julia; Pallardy, Marc; Lombardi, Vincent; Nony, Emmanuel; Baron-Bodo, Véronique; Mascarell, Laurent; Moingeon, Philippe

    2016-02-01

    Regulatory dendritic cell (DC) markers, such as C1Q, are upregulated in PBMCs of patients with grass pollen allergy exhibiting clinical benefit during allergen immunotherapy (AIT). We sought to define markers differentially expressed in human monocyte-derived DCs differentiated toward a proallergic (DCs driving the differentiation of TH2 cells [DC2s]) phenotype and investigate whether changes in such markers in the blood correlate with AIT efficacy. Transcriptomes and proteomes of monocyte-derived DCs polarized toward DCs driving the differentiation of TH1 cells (DC1s), DC2s, or DCs driving the differentiation of regulatorycells (DCreg cells) profiles were compared by using genome-wide cDNA microarrays and label-free quantitative proteomics, respectively. Markers differentially regulated in DC2s and DCreg cells were assessed by means of quantitative PCR in PBMCs from 80 patients with grass pollen allergy before and after 2 or 4 months of sublingual AIT in parallel with rhinoconjunctivitis symptom scores. We identified 20 and 26 new genes/proteins overexpressed in DC2s and DCreg cells, respectively. At an individual patient level, DC2-associated markers, such as CD141, GATA3, OX40 ligand, and receptor-interacting serine/threonine-protein kinase 4 (RIPK4), were downregulated after a 4-month sublingual AIT course concomitantly with an upregulation of DCreg cell-associated markers, including complement C1q subcomponent subunit A (C1QA), FcγRIIIA, ferritin light chain (FTL), and solute carrier organic anion transporter family member 2B1 (SLCO2B1), in the blood of clinical responders as opposed to nonresponders. Changes in such markers were better correlated with clinical benefit than alterations of allergen-specific CD4(+) T-cell or IgG responses. A combination of 5 markers predominantly expressed by blood DCs (ie, C1Q and CD141) or shared with lymphoid cells (ie, FcγRIIIA, GATA3, and RIPK4) reflecting changes in the balance of regulatory/proallergic responses

  5. 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.

  6. Induction of RNA interference in dendritic cells.

    Science.gov (United States)

    Li, Mu; Qian, Hua; Ichim, Thomas E; Ge, Wei-Wen; Popov, Igor A; Rycerz, Katarzyna; Neu, John; White, David; Zhong, Robert; Min, Wei-Ping

    2004-01-01

    Dendritic cells (DC) reside at the center of the immunological universe, possessing the ability both to stimulate and inhibit various types of responses. Tolerogenic/regulatory DC with therapeutic properties can be generated through various means of manipulations in vitro and in vivo. Here we describe several attractive strategies for manipulation of DC using the novel technique of RNA interference (RNAi). Additionally, we overview some of our data regarding yet undescribed characteristics of RNAi in DC such as specific transfection strategies, persistence of gene silencing, and multi-gene silencing. The advantages of using RNAi for DC genetic manipulation gives rise to the promise of generating tailor-made DC that can be used effectively to treat a variety of immunologically mediated diseases.

  7. Increased level of both CD4+FOXP3+ regulatory T cells and CD14+HLA-DR⁻/low myeloid-derived suppressor cells and decreased level of dendritic cells in patients with multiple myeloma

    DEFF Research Database (Denmark)

    Brimnes, M K; Vangsted, Annette Juul; Knudsen, L M

    2010-01-01

    Patients with multiple myeloma (MM) suffer from a general impaired immunity comprising deficiencies in humoral responses, T-cell responses as well as dendritic cell (DC) function. Thus, to achieve control of tumour growth through immune therapy constitutes a challenge. Careful evaluation of the i......Patients with multiple myeloma (MM) suffer from a general impaired immunity comprising deficiencies in humoral responses, T-cell responses as well as dendritic cell (DC) function. Thus, to achieve control of tumour growth through immune therapy constitutes a challenge. Careful evaluation...

  8. Donor-Derived Regulatory Dendritic Cell Infusion Maintains Donor-Reactive CD4+CTLA4hi T Cells in Non-Human Primate Renal Allograft Recipients Treated with CD28 Co-Stimulation Blockade

    Directory of Open Access Journals (Sweden)

    Mohamed B. Ezzelarab

    2018-02-01

    Full Text Available Donor-derived regulatory dendritic cell (DCreg infusion before transplantation, significantly prolongs renal allograft survival in non-human primates. This is associated with enhanced expression of the immunoregulatory molecules cytotoxic T-lymphocyte-associated antigen (Ag 4 (CTLA4 and programmed cell death protein 1 (PD1 by host donor-reactive T cells. In rodents and humans, CD28 co-stimulatory pathway blockade with the fusion protein CTLA4:Ig (CTLA4Ig is associated with reduced differentiation and development of regulatory T cells (Treg. We hypothesized that upregulation of CTLA4 by donor-reactive CD4+ T cells in DCreg-infused recipients treated with CTLA4Ig, might be associated with higher incidences of donor-reactive CD4+ T cells with a Treg phenotype. In normal rhesus monkeys, allo-stimulated CD4+CTLA4hi, but not CD4+CTLA4med/lo T cells exhibited a regulatory phenotype, irrespective of PD1 expression. CTLA4Ig significantly reduced the incidence of CD4+CTLA4hi, but not CD4+CTLA4med/lo T cells following allo-stimulation, associated with a significant reduction in the CD4+CTLA4hi/CD4+CTLA4med/lo T cell ratio. In CTLA4Ig-treated renal allograft recipient monkeys, there was a marked reduction in circulating donor-reactive CD4+CTLA4hi T cells. In contrast, in CTLA4Ig-treated monkeys with DCreg infusion, no such reduction was observed. In parallel, the donor-reactive CD4+CTLA4hi/CD4+CTLA4med/lo T cell ratio was reduced significantly in graft recipients without DCreg infusion, but increased in those given DCreg. These observations suggest that pre-transplant DCreg infusion promotes and maintains donor-reactive CD4+CTLA4hi T cells with a regulatory phenotype after transplantation, even in the presence of CD28 co-stimulation blockade.

  9. Eomesodermin(lo) CTLA4(hi) Alloreactive CD8+ Memory T Cells Are Associated With Prolonged Renal Transplant Survival Induced by Regulatory Dendritic Cell Infusion in CTLA4 Immunoglobulin-Treated Nonhuman Primates.

    Science.gov (United States)

    Ezzelarab, Mohamed B; Lu, Lien; Guo, Hao; Zahorchak, Alan F; Shufesky, William F; Cooper, David K C; Morelli, Adrian E; Thomson, Angus W

    2016-01-01

    Memory T cells (Tmem), particularly those resistant to costimulation blockade (CB), are a major barrier to transplant tolerance. The transcription factor Eomesodermin (Eomes) is critical for Tmem development and maintenance, but its expression by alloactivated T cells has not been examined in nonhuman primates. We evaluated Eomes and coinhibitory cytotoxic T lymphocyte antigen-4 (CTLA4) expression by alloactivated rhesus monkey T cells in the presence of CTLA4 immunoglobulin, both in vitro and in renal allograft recipients treated with CTLA4Ig, with or without regulatory dendritic cell (DCreg) infusion. In normal monkeys, CD8+ T cells expressed significantly more Eomes than CD4+ T cells. By contrast, CD8+ T cells displayed minimal CTLA4. Among T cell subsets, central Tmem (Tcm) expressed the highest levels of Eomes. Notably, Eomes(lo)CTLA4(hi) cells displayed higher levels of CD25 and Foxp3 than Eomes(hi)CTLA4(lo) CD8+ T cells. After allostimulation, distinct proliferating Eomes(lo)CTLA4(hi) and Eomes(hi)CTLA4(lo) CD8+ T cell populations were identified, with a high proportion of Tcm being Eomes(lo)CTLA4(hi). CB with CTLA4Ig during allostimulation of CD8+ T cells reduced CTLA4 but not Eomes expression, significantly reducing Eomes(lo)CTLA4(hi) cells. After transplantation with CB and rapamycin, donor-reactive Eomes(lo)CTLA4(hi) CD8+ T cells were reduced. However, in monkeys also given DCreg, absolute numbers of these cells were elevated significantly. Low Eomes and high CTLA4 expression by donor-reactive CD8+ Tmem is associated with prolonged renal allograft survival induced by DCreg infusion in CTLA4Ig-treated monkeys. Prolonged allograft survival associated with DCreg infusion may be related to maintenance of donor-reactive Eomes(lo)CTLA4(hi) Tcm.

  10. Eomesoderminlo CTLA4hi Alloreactive CD8+ Memory T Cells Are Associated With Prolonged Renal Transplant Survival Induced by Regulatory Dendritic Cell Infusion in CTLA4Ig-Treated Non-Human Primates

    Science.gov (United States)

    Ezzelarab, Mohamed B.; Lu, Lien; Guo, Hao; Zahorchak, Alan F.; Shufesky, William F.; Cooper, David K.C.; Morelli, Adrian E.; Thomson, Angus W.

    2015-01-01

    Background Memory T cells (Tmem), particularly those resistant to costimulation blockade (CB), are a major barrier to transplant tolerance. The transcription factor Eomesodermin (Eomes) is critical for Tmem development and maintenance, but its expression by alloactivated T cells has not been examined in non-human primates. Methods We evaluated Eomes and co-inhibitory cytotoxic T lymphocyte antigen-4 (CTLA4) expression by alloactivated rhesus monkey T cells in the presence of CTLA4 immunoglobulin (Ig), both in vitro and in renal allograft recipients treated with CTLA4Ig, with or without regulatory dendritic cell (DCreg) infusion. Results In normal monkeys, CD8+ T cells expressed significantly more Eomes than CD4+T cells. By contrast, CD8+T cells displayed minimal CTLA4. Among T cell subsets, central Tmem (Tcm) expressed the highest levels of Eomes. Notably, EomesloCTLA4hi cells displayed higher levels of CD25 and Foxp3 than EomeshiCTLA4lo CD8+ T cells. Following allostimulation, distinct proliferating EomesloCTLA4hi and EomeshiCTLA4lo CD8+ T cell populations were identified, with a high proportion of Tcm being EomesloCTLA4hi. CB with CTLA4Ig during allostimulation of CD8+T cells reduced CTLA4 but not Eomes expression, significantly reducing EomesloCTLA4hi cells. After transplantation with CB and rapamycin, donor-reactive EomesloCTLA4hi CD8+T cells were reduced. However, in monkeys also given DCreg, absolute numbers of these cells were elevated significantly. Conclusions Low Eomes and high CTLA4 expression by donor-reactive CD8+ Tmem is associated with prolonged renal allograft survival induced by DCreg infusion in CTLA4Ig-treated monkeys. Prolonged allograft survival associated with DCreg infusion may be related to maintenance of donor-reactive EomesloCTLA4hi Tcm. PMID:26680373

  11. 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...

  12. Dendritic cell-based immunotherapy.

    Science.gov (United States)

    Osada, Takuya; Clay, Timothy M; Woo, Christopher Y; Morse, Michael A; Lyerly, H Kim

    2006-01-01

    Dendritic cells (DCs) play a crucial role in the induction of antigen-specific T-cell responses, and therefore their use for the active immunotherapy of malignancies has been studied with considerable interest. More than a decade has passed since the publication of the first clinical data of DC-based vaccines, and through this and subsequent studies, a number of important developmental insights have been gleaned. These include the ideal source and type of DCs, the discovery of novel antigens and methods of loading DCs, the role of DC maturation, and the most efficient route of immunization. The generation of immune responses against tumor antigens after DC immunization has been demonstrated, and favorable clinical responses have been reported in some patients; however, it is difficult to pool the results as a whole, and thus the body of data remains inconclusive, in part because of varying DC preparation and vaccination protocols, the use of different forms of antigens, and, most importantly, a lack of rigorous criteria for defining clinical responses. As such, the standardization of clinical and immunologic criteria utilized, as well as DC preparations employed, will allow for the comparison of results across multiple clinical studies and is required in order for future trials to measure the true value and role of this treatment modality. In addition, issues regarding the optimal dose and clinical setting for the application of DC vaccines remain to be resolved, and recent clinical studies have been designed to begin to address these questions.

  13. Involvement of dendritic cells in allograft rejection new implications of dendritic cell-endothelial cell interactions.

    Science.gov (United States)

    Schlichting, C L; Schareck, W D; Kofler, S; Weis, M

    2007-04-01

    For almost half a century immunologists have tried to tear down the MHC barrier, which separates two unrelated individuals during transplantation. Latest experimental data suggest that a breakthrough in vitro is imminent. Dendritic cells (DCs), which activate naïve allo-reactive T-cells (TCs), play a central role in the establishment of allo-antigen-specific immunity. Allograft solid organ rejection is initiated at the foreign endothelial cell (EC) layer, which forms an immunogenic barrier for migrating DCs. Thus, DC/EC interactions might play a crucial role in antigen-specific allograft rejection. Organ rejection is mediated by host allo-reactive TCs, which are activated by donor DCs (direct activation) or host DCs (indirect activation). Direct allo-antigen presentation by regulatory dendritic cells (DCreg) can play an instructive role towards tolerance induction. Several groups established that, DCregs, if transplanted beforehand, enter host thymus, spleen, or bone marrow where they might eventually establish allo-antigen-specific tolerance. A fundamental aspect of DC function is migration throughout the entire organism. After solid organ transplantation, host DCs bind to ECs, invade allograft tissues, and finally transmigrate into lymphoid vessels and secondary lymphoid organs, where they present allo-antigens to naïve host TCs. Recent data suggest that in vitro manipulated DCregs may mediate allo-transplantation tolerance induction. However, the fundamental mechanisms on how such DCregs cause host TCs in the periphery towards tolerance remain unclear. One very promising experimental concept is the simultaneous manipulation of DC direct and indirect TC activation/suppression, towards donor antigen-specific allo-transplantation tolerance. The allo-antigen-specific long-term tolerance induction mediated by DCreg pre-transplantation (with simultaneous short-term immunosuppression) has become reproducible in the laboratory animal setting. Despite the shortcomings

  14. Memory CD8+ T cells protect dendritic cells from CTL killing

    NARCIS (Netherlands)

    Watchmaker, Payal B.; Urban, Julie A.; Berk, Erik; Nakamura, Yutaro; Mailliard, Robbie B.; Watkins, Simon C.; van Ham, S. Marieke; Kalinski, Pawel

    2008-01-01

    CD8(+) T cells have been shown to be capable of either suppressing or promoting immune responses. To reconcile these contrasting regulatory functions, we compared the ability of human effector and memory CD8(+) T cells to regulate survival and functions of dendritic cells (DC). We report that, in

  15. 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...

  16. 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 ...

  17. Derp1-modified dendritic cells attenuate allergic inflammation by regulating the development of T helper type1(Th1)/Th2 cells and regulatory T cells in a murine model of allergic rhinitis.

    Science.gov (United States)

    Yu, Shaoqing; Han, Bing; Liu, Shuangxi; Wang, Hong; Zhuang, Wenjie; Huang, Yu; Zhang, Ruxin

    2017-10-01

    The CD4 + CD25 + Foxp3 + regulatory T cells (Tregs) are known to regulate Th2-induced allergic rhinitis (AR). In this study, we evaluated the efficacy of Derp1-modified dendritic cells (DCs) in AR immunotherapy. Derp1 was synthesized and transfected into DCs to generate Derp1-modified DCs. Phenotypes of Derp1-modified DCs were analyzed with flow cytometry using antibodies against DC markers CD11c, CD11b, CD59, CD103 and Toll-like receptor 1(TLR1). Four groups of subject mice were formed; the controls were treated with immature DCs, while the AR mice models were sensitized with Derp1(AR) and treated with DCs(DC-AR) or Derp1-modified DCs (Derp1DC-AR). The frequency of sneezing and scratching, eosinophil cell count, and Th1/Th2 ratio in the spleen were measured for all groups. The percentage of CD4 + CD25 + Foxp3 + Tregs in peripheral blood mononuclear cells was measured using flow cytometry; serum IgE, IgG1, and histamine were measured using enzyme-linked immunosorbent assay; expression levels of transcription factors T-bet, GATA3, Foxp3+ and IL-10 were analyzed using reverse transcription-polymerase chain reaction, and Western blot used in analyzed expression of Foxp3+ and IL-10 in nasal mucosa. Treatment with Derp1-modified DCs ameliorated the allergic response. The Derp1DC-AR group had significantly lower eosinophil cell count and the IgE, IgG1, and histamine levels than the AR and DC-AR groups, and higher mRNA levels of Th1 transcription factors T-bet, IL-10 and Foxp3 in nasal mucosa than DC-AR mice, but Th2 transcription factors GATA3 mRNA expression level has the opposite results. Furthermore, the Th1/Th2 ratio and percentage of CD4 + CD25 + Foxp3 + Tregs was significantly lower in the AR group (pTh1/Th2, showing an immunotherapeutic effect against AR. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Fast generation of dendritic cells

    DEFF Research Database (Denmark)

    Kvistborg, P; Bøgh, Marie; Pedersen, A W

    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....

  19. Antigen dynamics of follicular dendritic cells

    NARCIS (Netherlands)

    Heesters, B.A.

    2015-01-01

    Stromal-derived follicular dendritic cells (FDCs) are a major depot for antigen that are essential for formation of germinal centers, the site where memory and effector B cells differentiate and high-affinity antibody production takes place. Historically, FDCs have been characterized as ‘accessory’

  20. Dendritic cells: biology of the skin

    NARCIS (Netherlands)

    Toebak, M.J.; Gibbs, S.; Bruynzeel, D.P.; Scheper, R.J.; Rustemeyer, T.

    2009-01-01

    Allergic contact dermatitis results from a T-cell-mediated, delayed-type hypersensitivity immune response induced by allergens. Skin dendritic cells (DCs) play a central role in the initiation of allergic skin responses. Following encounter with an allergen, DCs become activated and undergo

  1. Regulatory Myeloid Cells in Transplantation

    Science.gov (United States)

    Rosborough, Brian R.; Raïch-Regué, Dàlia; Turnquist, Heth R.; Thomson, Angus W.

    2013-01-01

    Regulatory myeloid cells (RMC) are emerging as novel targets for immunosuppressive (IS) agents and hold considerable promise as cellular therapeutic agents. Herein, we discuss the ability of regulatory macrophages (Mreg), regulatory dendritic cells (DCreg) and myeloid-derived suppressor cells (MDSC) to regulate alloimmunity, their potential as cellular therapeutic agents and the IS agents that target their function. We consider protocols for the generation of RMC and the selection of donor- or recipient-derived cells for adoptive cell therapy. Additionally, the issues of cell trafficking and antigen (Ag) specificity following RMC transfer are discussed. Improved understanding of the immunobiology of these cells has increased the possibility of moving RMC into the clinic to reduce the burden of current IS agents and promote Ag-specific tolerance. In the second half of this review, we discuss the influence of established and experimental IS agents on myeloid cell populations. IS agents believed historically to act primarily on T cell activation and proliferation are emerging as important regulators of RMC function. Better insights into the influence of IS agents on RMC will enhance our ability to develop cell therapy protocols to promote the function of these cells. Moreover, novel IS agents may be designed to target RMC in situ to promote Ag-specific immune regulation in transplantation and usher in a new era of immune modulation exploiting cells of myeloid origin. PMID:24092382

  2. Targeting nanoparticles to dendritic cells for immunotherapy.

    NARCIS (Netherlands)

    Cruz, L.J.; Tacken, P.J.; Rueda, F.; Domingo, J.C.; Albericio, F.; Figdor, C.G.

    2012-01-01

    Dendritic cells (DCs) are key players in the initiation of adaptive immune responses and are currently exploited in immunotherapy for treatment of cancer and infectious diseases. Development of targeted nanodelivery systems carrying vaccine components, including antigens and adjuvants, to DCs in

  3. 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...

  4. Human dendritic cell DC-SIGN and TLR-2 mediate complementary immune regulatory activities in response to Lactobacillus rhamnosus JB-1.

    Directory of Open Access Journals (Sweden)

    Patrycja Konieczna

    Full Text Available The microbiota is required for optimal host development and ongoing immune homeostasis. Lactobacilli are common inhabitants of the mammalian large intestine and immunoregulatory effects have been described for certain, but not all, strains. The mechanisms underpinning these protective effects are beginning to be elucidated. One such protective organism is Lactobacillus rhamnosus JB-1 (Lb. rhamnosus JB-1. Lb. murinus has no such anti-inflammatory protective effects and was used as a comparator organism. Human monocyte-derived dendritic cells (MDDCs were co-incubated with bacteria and analysed over time for bacterial adhesion and intracellular processing, costimulatory molecule expression, cytokine secretion and induction of lymphocyte polarization. Neutralising antibodies were utilized to identify the responsible MDDC receptors. Lb. rhamnosus JB-1 adhered to MDDCs, but internalization and intracellular processing was significantly delayed, compared to Lb. murinus which was rapidly internalized and processed. Lb. murinus induced CD80 and CD86 expression, accompanied by high levels of cytokine secretion, while Lb. rhamnosus JB-1 was a poor inducer of costimulatory molecule expression and cytokine secretion. Lb. rhamnosus JB-1 primed MDDCs induced Foxp3 expression in autologous lymphocytes, while Lb. murinus primed MDDCs induced Foxp3, T-bet and Ror-γt expression. DC-SIGN was required for Lb. rhamnosus JB-1 adhesion and influenced IL-12 secretion, while TLR-2 influenced IL-10 and IL-12 secretion. Here we demonstrate that the delayed kinetics of bacterial processing by MDDCs correlates with MDDC activation and stimulation of lymphocytes. Thus, inhibition or delay of intracellular processing may be a novel strategy by which certain commensals may avoid the induction of proinflammatory responses.

  5. Human Dendritic Cell DC-SIGN and TLR-2 Mediate Complementary Immune Regulatory Activities in Response to Lactobacillus rhamnosus JB-1

    Science.gov (United States)

    Konieczna, Patrycja; Schiavi, Elisa; Ziegler, Mario; Groeger, David; Healy, Selena; Grant, Ray; O’Mahony, Liam

    2015-01-01

    The microbiota is required for optimal host development and ongoing immune homeostasis. Lactobacilli are common inhabitants of the mammalian large intestine and immunoregulatory effects have been described for certain, but not all, strains. The mechanisms underpinning these protective effects are beginning to be elucidated. One such protective organism is Lactobacillus rhamnosus JB-1 (Lb. rhamnosus JB-1). Lb. murinus has no such anti-inflammatory protective effects and was used as a comparator organism. Human monocyte-derived dendritic cells (MDDCs) were co-incubated with bacteria and analysed over time for bacterial adhesion and intracellular processing, costimulatory molecule expression, cytokine secretion and induction of lymphocyte polarization. Neutralising antibodies were utilized to identify the responsible MDDC receptors. Lb. rhamnosus JB-1 adhered to MDDCs, but internalization and intracellular processing was significantly delayed, compared to Lb. murinus which was rapidly internalized and processed. Lb. murinus induced CD80 and CD86 expression, accompanied by high levels of cytokine secretion, while Lb. rhamnosus JB-1 was a poor inducer of costimulatory molecule expression and cytokine secretion. Lb. rhamnosus JB-1 primed MDDCs induced Foxp3 expression in autologous lymphocytes, while Lb. murinus primed MDDCs induced Foxp3, T-bet and Ror-γt expression. DC-SIGN was required for Lb. rhamnosus JB-1 adhesion and influenced IL-12 secretion, while TLR-2 influenced IL-10 and IL-12 secretion. Here we demonstrate that the delayed kinetics of bacterial processing by MDDCs correlates with MDDC activation and stimulation of lymphocytes. Thus, inhibition or delay of intracellular processing may be a novel strategy by which certain commensals may avoid the induction of proinflammatory responses. PMID:25816321

  6. Human dendritic cell DC-SIGN and TLR-2 mediate complementary immune regulatory activities in response to Lactobacillus rhamnosus JB-1.

    Science.gov (United States)

    Konieczna, Patrycja; Schiavi, Elisa; Ziegler, Mario; Groeger, David; Healy, Selena; Grant, Ray; O'Mahony, Liam

    2015-01-01

    The microbiota is required for optimal host development and ongoing immune homeostasis. Lactobacilli are common inhabitants of the mammalian large intestine and immunoregulatory effects have been described for certain, but not all, strains. The mechanisms underpinning these protective effects are beginning to be elucidated. One such protective organism is Lactobacillus rhamnosus JB-1 (Lb. rhamnosus JB-1). Lb. murinus has no such anti-inflammatory protective effects and was used as a comparator organism. Human monocyte-derived dendritic cells (MDDCs) were co-incubated with bacteria and analysed over time for bacterial adhesion and intracellular processing, costimulatory molecule expression, cytokine secretion and induction of lymphocyte polarization. Neutralising antibodies were utilized to identify the responsible MDDC receptors. Lb. rhamnosus JB-1 adhered to MDDCs, but internalization and intracellular processing was significantly delayed, compared to Lb. murinus which was rapidly internalized and processed. Lb. murinus induced CD80 and CD86 expression, accompanied by high levels of cytokine secretion, while Lb. rhamnosus JB-1 was a poor inducer of costimulatory molecule expression and cytokine secretion. Lb. rhamnosus JB-1 primed MDDCs induced Foxp3 expression in autologous lymphocytes, while Lb. murinus primed MDDCs induced Foxp3, T-bet and Ror-γt expression. DC-SIGN was required for Lb. rhamnosus JB-1 adhesion and influenced IL-12 secretion, while TLR-2 influenced IL-10 and IL-12 secretion. Here we demonstrate that the delayed kinetics of bacterial processing by MDDCs correlates with MDDC activation and stimulation of lymphocytes. Thus, inhibition or delay of intracellular processing may be a novel strategy by which certain commensals may avoid the induction of proinflammatory responses.

  7. IRF8 Transcription Factor Controls Survival and Function of Terminally Differentiated Conventional and Plasmacytoid Dendritic Cells, Respectively

    DEFF Research Database (Denmark)

    Sichien, Dorine; Scott, Charlotte L; Martens, Liesbet

    2016-01-01

    Interferon regulatory factor-8 (IRF8) has been proposed to be essential for development of monocytes, plasmacytoid dendritic cells (pDCs) and type 1 conventional dendritic cells (cDC1s) and remains highly expressed in differentiated DCs. Transcription factors that are required to maintain the ide...

  8. Dendritic cell fate is determined by BCL11A

    Science.gov (United States)

    Ippolito, Gregory C.; Dekker, Joseph D.; Wang, Yui-Hsi; Lee, Bum-Kyu; Shaffer, Arthur L.; Lin, Jian; Wall, Jason K.; Lee, Baeck-Seung; Staudt, Louis M.; Liu, Yong-Jun; Iyer, Vishwanath R.; Tucker, Haley O.

    2014-01-01

    The plasmacytoid dendritic cell (pDC) is vital to the coordinated action of innate and adaptive immunity. pDC development has not been unequivocally traced, nor has its transcriptional regulatory network been fully clarified. Here we confirm an essential requirement for the BCL11A transcription factor in fetal pDC development, and demonstrate this lineage-specific requirement in the adult organism. Furthermore, we identify BCL11A gene targets and provide a molecular mechanism for its action in pDC commitment. Embryonic germ-line deletion of Bcl11a revealed an absolute cellular, molecular, and functional absence of pDCs in fetal mice. In adults, deletion of Bcl11a in hematopoietic stem cells resulted in perturbed yet continued generation of progenitors, loss of downstream pDC and B-cell lineages, and persisting myeloid, conventional dendritic, and T-cell lineages. Challenge with virus resulted in a marked reduction of antiviral response in conditionally deleted adults. Genome-wide analyses of BCL11A DNA binding and expression revealed that BCL11A regulates transcription of E2-2 and other pDC differentiation modulators, including ID2 and MTG16. Our results identify BCL11A as an essential, lineage-specific factor that regulates pDC development, supporting a model wherein differentiation into pDCs represents a primed “default” pathway for common dendritic cell progenitors. PMID:24591644

  9. Chemoresistance of human monocyte-derived dendritic cells is regulated by IL-17A.

    Directory of Open Access Journals (Sweden)

    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

  10. 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.

  11. DMPD: The role of the interferon regulatory factor (IRF) family in dendritic celldevelopment and function. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 17702640 The role of the interferon regulatory factor (IRF) family in dendritic celldevelopment and function...in dendritic celldevelopment and function. PubmedID 17702640 Title The role of th...e interferon regulatory factor (IRF) family in dendritic celldevelopment and function. Authors Gabriele L, O

  12. 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.

  13. Dendritic cells during Epstein Barr virus infection

    Directory of Open Access Journals (Sweden)

    Christian eMunz

    2014-06-01

    Full Text Available Epstein Barr virus (EBV causes persistent infection in more than 90% of the human adult population and is associated with 2% of all tumors in humans. This -herpesvirus infects primarily human B and epithelial cells, but has been reported to be sensed by dendritic cells (DCs during primary infection. These activated DCs are thought to contribute to innate restriction of EBV infection and initiate EBV specific adaptive immune responses via cross-priming. The respective evidence and their potential importance for EBV specific vaccine development will be discussed in this review.

  14. 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....... 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...

  15. 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....

  16. 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.

  17. Plasmacytoid dendritic cells are crucial in Bifidobacterium adolescentis-mediated inhibition of Yersinia enterocolitica infection.

    Directory of Open Access Journals (Sweden)

    Alexandra Wittmann

    Full Text Available In industrialized countries bacterial intestinal infections are commonly caused by enteropathogenic Enterobacteriaceae. The interaction of the microbiota with the host immune system determines the adequacy of an appropriate response against pathogens. In this study we addressed whether the probiotic Bifidobacterium adolescentis is protective during intestinal Yersinia enterocolitica infection. Female C57BL/6 mice were fed with B. adolescentis, infected with Yersinia enterocolitica, or B. adolescentis fed and subsequently infected with Yersinia enterocolitica. B. adolescentis fed and Yersinia infected mice were protected from Yersinia infection as indicated by a significantly reduced weight loss and splenic Yersinia load when compared to Yersinia infected mice. Moreover, protection from infection was associated with increased intestinal plasmacytoid dendritic cell and regulatory T-cell frequencies. Plasmacytoid dendritic cell function was investigated using depletion experiments by injecting B. adolescentis fed, Yersinia infected C57BL/6 mice with anti-mouse PDCA-1 antibody, to deplete plasmacytoid dendritic cells, or respective isotype control. The B. adolescentis-mediated protection from Yersinia dissemination to the spleen was abrogated after plasmacytoid dendritic cell depletion indicating a crucial function for pDC in control of intestinal Yersinia infection. We suggest that feeding of B. adolescentis modulates the intestinal immune system in terms of increased plasmacytoid dendritic cell and regulatory T-cell frequencies, which might account for the B. adolescentis-mediated protection from Yersinia enterocolitica infection.

  18. Plasmacytoid dendritic cells are crucial in Bifidobacterium adolescentis-mediated inhibition of Yersinia enterocolitica infection.

    Science.gov (United States)

    Wittmann, Alexandra; Autenrieth, Ingo B; Frick, Julia-Stefanie

    2013-01-01

    In industrialized countries bacterial intestinal infections are commonly caused by enteropathogenic Enterobacteriaceae. The interaction of the microbiota with the host immune system determines the adequacy of an appropriate response against pathogens. In this study we addressed whether the probiotic Bifidobacterium adolescentis is protective during intestinal Yersinia enterocolitica infection. Female C57BL/6 mice were fed with B. adolescentis, infected with Yersinia enterocolitica, or B. adolescentis fed and subsequently infected with Yersinia enterocolitica. B. adolescentis fed and Yersinia infected mice were protected from Yersinia infection as indicated by a significantly reduced weight loss and splenic Yersinia load when compared to Yersinia infected mice. Moreover, protection from infection was associated with increased intestinal plasmacytoid dendritic cell and regulatory T-cell frequencies. Plasmacytoid dendritic cell function was investigated using depletion experiments by injecting B. adolescentis fed, Yersinia infected C57BL/6 mice with anti-mouse PDCA-1 antibody, to deplete plasmacytoid dendritic cells, or respective isotype control. The B. adolescentis-mediated protection from Yersinia dissemination to the spleen was abrogated after plasmacytoid dendritic cell depletion indicating a crucial function for pDC in control of intestinal Yersinia infection. We suggest that feeding of B. adolescentis modulates the intestinal immune system in terms of increased plasmacytoid dendritic cell and regulatory T-cell frequencies, which might account for the B. adolescentis-mediated protection from Yersinia enterocolitica infection.

  19. Dendritic Cells in the Gut: Interaction with Intestinal Helminths

    Directory of Open Access Journals (Sweden)

    Fela Mendlovic

    2010-01-01

    Full Text Available The mucosal environment in mammals is highly tolerogenic; however, after exposure to pathogens or danger signals, it is able to shift towards an inflammatory response. Dendritic cells (DCs orchestrate immune responses and are highly responsible, through the secretion of cytokines and expression of surface markers, for the outcome of such immune response. In particular, the DC subsets found in the intestine have specialized functions and interact with different immune as well as nonimmune cells. Intestinal helminths primarily induce Th2 responses where DCs have an important yet not completely understood role. In addition, this cross-talk results in the induction of regulatory T cells (T regs as a result of the homeostatic mucosal environment. This review highlights the importance of studying the particular relation “helminth-DC-milieu” in view of the significance that each of these factors plays. Elucidating the mechanisms that trigger Th2 responses may provide the understanding of how we might modulate inflammatory processes.

  20. Gliadin fragments promote migration of dendritic cells

    Czech Academy of Sciences Publication Activity Database

    Chládková, Barbara; Kamanová, Jana; Palová-Jelínková, Lenka; Cinová, Jana; Šebo, Peter; Tučková, Ludmila

    2011-01-01

    Roč. 15, č. 4 (2011), 938-948 ISSN 1582-1838 R&D Projects: GA ČR GA310/07/0414; GA ČR GD310/08/H077; GA ČR GA310/08/0447; GA AV ČR IAA500200801; GA AV ČR IAA500200914 Institutional research plan: CEZ:AV0Z50200510 Keywords : celiac disease * gliadin * dendritic cell Subject RIV: EC - Immunology Impact factor: 4.125, year: 2011

  1. Crosstalk between T lymphocytes and dendritic cells.

    Science.gov (United States)

    Hivroz, Claire; Chemin, Karine; Tourret, Marie; Bohineust, Armelle

    2012-01-01

    Dendritic cells (DCs) are professional antigen-presenting cells (APCs) with the unique property of inducing priming and differentiation of naïve CD4+ and CD8+ T cells into helper and cytotoxic effectors. Their efficiency is due to their unique ability to process antigen, express costimulatory molecules, secrete cytokines, and migrate to tissues or lymphoid organs to prime T cells. DCs also play an important role in T-cell peripheral tolerance. There is ample evidence that the DC ability to present antigens is regulated by CD4+ helper T cells. Indeed, interactions between surface receptors and ligands expressed respectively by T cells and DCs, as well as T-cell-derived cytokines modify DC functions. This T-cell-induced modification of DCs has been called "education" or "licensing." This intimate crosstalk between DCs and T lymphocytes is key in establishing appropriate adaptive immune responses. It requires cognate interactions between T lymphocytes and DCs, which are organized in time and space by structures called immunological synapses. Here we discuss the particular aspects of immunological synapses formed between T cells and DCs and the role these organized interactions have in T-cell-DC crosstalk.

  2. 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...

  3. Dendritic cells limit fibroinflammatory injury in nonalcoholic steatohepatitis in mice.

    Science.gov (United States)

    Henning, Justin R; Graffeo, Christopher S; Rehman, Adeel; Fallon, Nina C; Zambirinis, Constantinos P; Ochi, Atsuo; Barilla, Rocky; Jamal, Mohsin; Deutsch, Michael; Greco, Stephanie; Ego-Osuala, Melvin; Bin-Saeed, Usama; Rao, Raghavendra S; Badar, Sana; Quesada, Juan P; Acehan, Devrim; Miller, George

    2013-08-01

    Nonalcoholic steatohepatitis (NASH) is the most common etiology of chronic liver dysfunction in the United States and can progress to cirrhosis and liver failure. Inflammatory insult resulting from fatty infiltration of the liver is central to disease pathogenesis. Dendritic cells (DCs) are antigen-presenting cells with an emerging role in hepatic inflammation. We postulated that DCs are important in the progression of NASH. We found that intrahepatic DCs expand and mature in NASH liver and assume an activated immune phenotype. However, rather than mitigating the severity of NASH, DC depletion markedly exacerbated intrahepatic fibroinflammation. Our mechanistic studies support a regulatory role for DCs in NASH by limiting sterile inflammation through their role in the clearance of apoptotic cells and necrotic debris. We found that DCs limit CD8(+) T-cell expansion and restrict Toll-like receptor expression and cytokine production in innate immune effector cells in NASH, including Kupffer cells, neutrophils, and inflammatory monocytes. Consistent with their regulatory role in NASH, during the recovery phase of disease, ablation of DC populations results in delayed resolution of intrahepatic inflammation and fibroplasia. Our findings support a role for DCs in modulating NASH. Targeting DC functional properties may hold promise for therapeutic intervention in NASH. Copyright © 2013 American Association for the Study of Liver Diseases.

  4. Dendritic Cells Limit Fibro-Inflammatory Injury in NASH

    Science.gov (United States)

    Henning, Justin R.; Graffeo, Christopher S.; Rehman, Adeel; Fallon, Nina C.; Zambirinis, Constantinos P.; Ochi, Atsuo; Barilla, Rocky; Jamal, Mohsin; Deutsch, Michael; Greco, Stephanie; Ego-Osuala, Melvin; Saeed, Usama Bin; Rao, Raghavendra S.; Badar, Sana; Quesada, Juan P.; Acehan, Devrim; Miller, George

    2013-01-01

    Non-alcoholic steatohepatitis (NASH) is the most common etiology of chronic liver dysfunction in the United States and can progress to cirrhosis and liver failure. Inflammatory insult resulting from fatty infiltration of the liver is central to disease pathogenesis. Dendritic cells (DC) are antigen presenting cells with an emerging role in hepatic inflammation. We postulated that DC are important in the progression of NASH. We found that intrahepatic DC expand and mature in NASH liver and assume an activated immune-phenotype. However, rather than mitigating the severity of NASH, DC depletion markedly exacerbated intrahepatic fibro-inflammation. Our mechanistic studies support a regulatory role for DC in NASH by limiting sterile inflammation via their role in clearance of apoptotic cells and necrotic debris. We found that DC limit CD8+ T cell expansion and restrict Toll-like receptor expression and cytokine production in innate immune effector cells in NASH, including Kupffer cells, neutrophils, and inflammatory monocytes. Consistent with their regulatory role in NASH, during the recovery phase of disease, ablation of DC populations results in delayed resolution of intrahepatic inflammation and fibroplasia. Conclusion Our findings support a role for DC in modulating NASH. Targeting DC functional properties may hold promise for therapeutic intervention in NASH. PMID:23322710

  5. 3-bromopyruvate ameliorate autoimmune arthritis by modulating Th17/Treg cell differentiation and suppressing dendritic cell activation

    OpenAIRE

    Okano, Takaichi; Saegusa, Jun; Nishimura, Keisuke; Takahashi, Soshi; Sendo, Sho; Ueda, Yo; Morinobu, Akio

    2017-01-01

    Recent studies have shown that cellular metabolism plays an important role in regulating immune cell functions. In immune cell differentiation, both interleukin-17-producing T (Th17) cells and dendritic cells (DCs) exhibit increased glycolysis through the upregulation of glycolytic enzymes, such as hexokinase-2 (HK2). Blocking glycolysis with 2-deoxyglucose was recently shown to inhibit Th17 cell differentiation while promoting regulatory T (Treg) cell generation. However, 2-DG inhibits all i...

  6. Dendritic cells recognize tumor-specific glycosylation of carcinoembryonic antigen on colorectal cancer cells through dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin

    NARCIS (Netherlands)

    van Gisbergen, Klaas P. J. M.; Aarnoudse, Corlien A.; Meijer, Gerrit A.; Geijtenbeek, Teunis B. H.; van Kooyk, Yvette

    2005-01-01

    Dendritic cells play a pivotal role in the induction of antitumor immune responses. Immature dendritic cells are located intratumorally within colorectal cancer and intimately interact with tumor cells, whereas mature dendritic cells are present peripheral to the tumor. The majority of colorectal

  7. The Regulatory Roles of Toll-Like Receptor 4 in Secretions of Type 1/Type 2 Relative Cytokines by Splenocytes and Dendritic Cells Exposed to Clonorchis sinensis Excretory/Secretory Products.

    Science.gov (United States)

    Hua, Hui; Du, Ying; Ma, Rui; Zhang, Bei-Bei; Yu, Qian; Li, Bo; Xu, Jiang-Tao; Li, Xiang-Yang; Tang, Ren-Xian; Yan, Chao; Zheng, Kui-Yang

    2018-02-01

    The roles of TLR4 in mediation of innate immune response and in regulation of adaptive immune responses triggered by Clonorchis sinensis remain unknown. In the present study, splenocytes derived from C3H/HeN (TLR4 wild ) and C3H/Hej mice (TLR4 mut ) that were infected with 45 metacercariae of C. sinensis were harvested, then stimulated by C. sinensis excretory/secretory products (ESP) or medium (control) for 48 h, respectively. Meanwhile, bone marrow-derived dendritic cells (BMDCs) from normal C3H/HeN and C3H/Hej mice were prepared and stimulated with medium, ESP, LPS, or ESP+LPS for 24 h, respectively. The supernatants were collected, and the concentrations of type 1 and type 2 relative cytokines were determined by ELISA. The maturation of BMDCs indicated by surface markers of CD80, CD86, and MHC II was evaluated by flow cytometry. The results showed that the levels of IFN-γ, IL-6, TNF-α, and IL-10 in the splenocytes from C. sinensis-infected TLR4 mut mice were significantly lower than those from TLR4 wild mice when they were further exposed to ESP. For BMDCs, the productions of the cytokines IL-12p70 and IL-10, but not IL-4, in the BMDCs from TLR4 mutation mice were predominantly decreased compared with those from TLR4 wild mice when the BMDCs were co-stimulated by ESP combined with LPS. Flow cytometry analysis showed that ESP could significantly decrease the high levels of CD80, CD86, and MHC II which were elevated by LPS. In conclusion, these data suggest that TLR4 may play a regulatory role in type 1 immune responses during C. sinensis infection.

  8. Stimulation of dendritic cells enhances immune response after photodynamic therapy

    Science.gov (United States)

    Mroz, Pawel; Castano, Ana P.; Hamblin, Michael R.

    2009-02-01

    Photodynamic therapy (PDT) involves the administration of photosensitizers followed by illumination of the primary tumor with red light producing reactive oxygen species that cause vascular shutdown and tumor cell necrosis and apoptosis. Anti-tumor immunity is stimulated after PDT due to the acute inflammatory response, priming of the immune system to recognize tumor-associated antigens (TAA). The induction of specific CD8+ Tlymphocyte cells that recognize major histocompatibility complex class I (MHC-I) restricted epitopes of TAAs is a highly desirable goal in cancer therapy. The PDT killed tumor cells may be phagocytosed by dendritic cells (DC) that then migrate to draining lymph nodes and prime naÃve T-cells that recognize TAA epitopes. This process is however, often sub-optimal, in part due to tumor-induced DC dysfunction. Instead of DC that can become mature and activated and have a potent antigen-presenting and immune stimulating phenotype, immature dendritic cells (iDC) are often found in tumors and are part of an immunosuppressive milieu including regulatory T-cells and immunosuppressive cytokines such as TGF-beta and IL10. We here report on the use of a potent DC activating agent, an oligonucleotide (ODN) that contains a non-methylated CpG motif and acts as an agonist of toll like receptor (TLR) 9. TLR activation is a danger signal to notify the immune system of the presence of invading pathogens. CpG-ODN (but not scrambled non-CpG ODN) increased bone-marrow DC activation after exposure to PDT-killed tumor cells, and significantly increased tumor response to PDT and mouse survival after peri-tumoral administration. CpG may be a valuable immunoadjuvant to PDT especially for tumors that produce DC dysfunction.

  9. Dendritic cells in Barrett's esophagus and esophageal adenocarcinoma.

    Science.gov (United States)

    Bobryshev, Yuri V; Tran, Dinh; Killingsworth, Murray C; Buckland, Michael; Lord, Reginald V N

    2009-01-01

    Like other premalignant conditions that develop in the presence of chronic inflammation, the development and progression of Barrett's esophagus is associated with the development of an immune response, but how this immune response is regulated is poorly understood. A comprehensive literature search failed to find any report of the presence of dendritic cells in Barrett's intestinal metaplasia and esophageal adenocarcinoma and this prompted our study. We used immunohistochemical staining and electron microscopy to examine whether dendritic cells are present in Barrett's esophagus and esophageal adenocarcinoma. Immunohistochemical staining with CD83, a specific marker for dendritic cells, was performed on paraffin-embedded sections of Barrett's intestinal metaplasia (IM, n = 12), dysplasia (n = 11) and adenocarcinoma (n = 14). CD83+ cells were identified in the lamina propria surrounding intestinal type glands in Barrett's IM, dysplasia, and cancer tissues. Computerized quantitative analysis showed that the numbers of dendritic cells were significantly higher in cancer tissues. Double immunostaining with CD83, CD20, and CD3, and electron microscopy demonstrated that dendritic cells are present in Barrett's esophagus and form clusters with T cells and B cells directly within the lamina propria. These findings demonstrate that dendritic cells are present in Barrett's tissues, with a significant increase in density in adenocarcinoma compared to benign Barrett's esophagus. Dendritic cells may have a role in the pathogenesis and immunotherapy treatment of Barrett's esophagus and adenocarcinoma.

  10. Low-Dose Cyclophosphamide Synergizes with Dendritic Cell-Based Immunotherapy in Antitumor Activity

    Directory of Open Access Journals (Sweden)

    Joris D. Veltman

    2010-01-01

    Full Text Available Clinical immunotherapy trials like dendritic cell-based vaccinations are hampered by the tumor's offensive repertoire that suppresses the incoming effector cells. Regulatory T cells are instrumental in suppressing the function of cytotoxic T cells. We studied the effect of low-dose cyclophosphamide on the suppressive function of regulatory T cells and investigated if the success rate of dendritic cell immunotherapy could be improved. For this, mesothelioma tumor-bearing mice were treated with dendritic cell-based immunotherapy alone or in combination with low-dose of cyclophosphamide. Proportions of regulatory T cells and the cytotoxic T cell functions at different stages of disease were analyzed. We found that low-dose cyclophosphamide induced beneficial immunomodulatory effects by preventing the induction of Tregs, and as a consequence, cytotoxic T cell function was no longer affected. Addition of cyclophosphamide improved immunotherapy leading to an increased median and overall survival. Future studies are needed to address the usefulness of this combination treatment for mesothelioma patients.

  11. 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.

  12. Vaccination of B-CLL patients with autologous dendritic cells can change the frequency of leukemia antigen-specific CD8+ T cells as well as CD4+CD25+FoxP3+ regulatory T cells toward an antileukemia response.

    Science.gov (United States)

    Hus, I; Schmitt, M; Tabarkiewicz, J; Radej, S; Wojas, K; Bojarska-Junak, A; Schmitt, A; Giannopoulos, K; Dmoszyńska, A; Roliński, J

    2008-05-01

    Recently, we described that vaccination with allogeneic dendritic cells (DCs) pulsed with tumor cell lysate generated specific CD8+ T cell response in patients with B-cell chronic lymphocytic leukemia (B-CLL). In the present study, the potential of autologous DCs pulsed ex vivo with tumor cell lysates to stimulate antitumor immunity in patients with B-CLL in early stages was evaluated. Twelve patients at clinical stage 0-2 as per Rai were vaccinated intradermally up to eight times with a mean number of 7.4 x 10(6) DCs pulsed with B-CLL cell lysate. We observed a decrease of peripheral blood leukocytes and CD19+/CD5+ leukemic cells in five patients, three patients showed a stable disease and four patients progressed despite DC vaccination. A significant increase of specific cytotoxic CD8+ T lymphocytes against the leukemia-associated antigens RHAMM or fibromodulin was detected in four patients after DC vaccination. In patients with a clinical response, an increase of interleukin 12 (IL-12) serum levels and a decrease of the frequency of CD4+CD25(+)FOXP3+ T regulatory cells were observed. Taken together, the study demonstrated that vaccination with autologous DC in CLL patients is feasible and safe. Immunological and to some extend hematological responses could be noted, justifying further investigation on this immunotherapeutical approach.

  13. Cross Talk between inhibitory immunoreceptor Tyrosine-Based Activation Motif-Signaling and Toll-Like Receptor Pathways in Macrophages and Dendritic Cells

    Czech Academy of Sciences Publication Activity Database

    Hirsch, Ivan; Janovec, Václav; Stranska, R.; Bendriss-Vermare, N.

    2017-01-01

    Roč. 8, Apr 7 (2017), č. článku 394. ISSN 1664-3224 Institutional support: RVO:61388963 Keywords : plasmacytoid dendritic cell * conventional dendritic cells * macrophage * toll-like receptors * regulatory receptors Subject RIV: EC - Immunology OBOR OECD: Immunology Impact factor: 6.429, year: 2016 http://journal.frontiersin.org/article/10.3389/fimmu.2017.00394/full

  14. 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. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. Equine dendritic cells generated with horse serum have enhanced functionality in comparison to dendritic cells generated with fetal bovine serum

    OpenAIRE

    Ziegler, Anja; Everett, Helen; Hamza, Eman; Garbani, Mattia; Gerber, Vinzenz; Marti, Eliane; Steinbach, Falko

    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 hor...

  16. Dendritic cells in oral tolerance in the gut.

    Science.gov (United States)

    Rescigno, Maria

    2011-09-01

    Oral tolerance is a process that allows generation of systemic unresponsiveness to food antigens. Hence if the same antigen is introduced systemically even under immunogenic conditions it does not induce immune responsiveness. Dendritic cells (DCs) have been identified as essential players in this process. DCs in the gut are located in a strategic position as they can interact directly with luminal antigens or indirectly after their transcytosis across epithelial cells. DCs can then migrate to associated lymphoid tissues to induce tolerance. Antigen presenting cells in the gut are specialized in function and have divided their labour so that there are cells capable to migrate to the draining mesenteric lymph node for induction of T regulatory cells, while other subsets are resident and are required to enforce tolerance locally in the gut after food antigen exposure. In this review, I shall summarize the characteristics of antigen presenting cells in the gut and their involvement in oral tolerance induction. In addition, I will also emphasize that tolerance to food allergens may be contributed by plasmacytoid DCs in the liver that participate to the elimination or anergy of allergen-specific CD8 T cells. Hence specialized functions are associated to different subsets of antigen presenting cells and different organs. © 2011 Blackwell Publishing Ltd.

  17. 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...... infiltrating human tumors, but less information is known about how these T-cells gain access to the tumor or how they are primed to become tumor-specific. Here, we highlight recent findings that demonstrate a vital role of CD103+ DCs, which have been shown to be experts in cross-priming and the induction...... of anti-tumor immunity. We also focus on two different mediators that impair the function of tumor-associated DCs: prostaglandin E2 and β-catenin. Both of these mediators seem to be important for the exclusion of T-cells in the tumor microenvironment and may represent key pathways to target in optimized...

  18. Dendritic cells in chronic myelomonocytic leukaemia.

    Science.gov (United States)

    Vuckovic, S; Fearnley, D B; Gunningham, S; Spearing, R L; Patton, W N; Hart, D N

    1999-06-01

    Blood dendritic cells (DC) differentiate in vitro via two separate pathways: either directly from blood DC precursors (DCp) or from CD14+ monocytes. In chronic myelomonocytic leukaemia (CMML) abnormal bone marrow precursors contribute to blood monocyte development but DC development has not been studied previously. Monocytes comprised 60% of blood MNC in 15 CMML patients studied, compared with 20% in 16 age-matched controls. The increase in blood monocytes was accompanied by a reciprocal decrease in mean blood DC percentage (from 0.42% of MNC in normal individuals to 0.16% of MNC in CMML patients). Absolute blood DC numbers showed a minimal (non-significant) reduction from 9.8 x 10(6)/l in normal individuals to 7.5 x 10(6)/l in CMML patients. The CD14(low) WCD16+ monocyte subpopulation was not found in CMML patients. After culture in GM-CSF/IL-4, CMML CD14+ monocytes acquired the phenotype of immature monocyte derived DC (Mo-DC) with similar yields to normal blood Mo-DC generation. Addition of TNF-alpha or LPS induced both normal and CMML Mo-DC to express prominent dendritic processes, the CMRF44+ and CD83+ antigens and high levels of HLA-DR, CD80 and CD86. Treatment either with TNF-alpha or LPS increased the allostimulatory activity of normal Mo-DC, but had little effect on the allostimulatory activity of CMML Mo-DC, perhaps reflecting the underlying neoplastic changes in monocyte precursors. We conclude that the blood DC numbers are relatively unaffected in CMML, suggesting discrete regulation of monocyte and DC production.

  19. Variability of doublecortin-associated dendrite maturation in adult hippocampal neurogenesis is independent of the regulation of precursor cell proliferation

    Directory of Open Access Journals (Sweden)

    Jessberger Sebastian

    2006-11-01

    Full Text Available Abstract Background In the course of adult hippocampal neurogenesis most regulation takes place during the phase of doublecortin (DCX expression, either as pro-proliferative effect on precursor cells or as survival-promoting effect on postmitotic cells. We here obtained quantitative data about the proliferative population and the dynamics of postmitotic dendrite development during the period of DCX expression. The question was, whether any indication could be obtained that the initiation of dendrite development is timely bound to the exit from the cell cycle. Alternatively, the temporal course of morphological maturation might be subject to additional regulatory events. Results We found that (1 20% of the DCX population were precursor cells in cell cycle, whereas more than 70% were postmitotic, (2 the time span until newborn cells had reached the most mature stage associated with DCX expression varied between 3 days and several weeks, (3 positive or negative regulation of precursor cell proliferation did not alter the pattern and dynamics of dendrite development. Dendrite maturation was largely independent of close contacts to astrocytes. Conclusion These data imply that dendrite maturation of immature neurons is initiated at varying times after cell cycle exit, is variable in duration, and is controlled independently of the regulation of precursor cell proliferation. We conclude that in addition to the major regulatory events in cell proliferation and selective survival, additional micro-regulatory events influence the course of adult hippocampal neurogenesis.

  20. Plasmacytoid dendritic cells: Development, functions, and role in atherosclerotic inflammation

    Directory of Open Access Journals (Sweden)

    Dimitry A Chistiakov

    2014-07-01

    Full Text Available Plasmacytoid dendritic cells (pDCs are a specialized subset of DCs that links innate and adaptive immunity. They sense viral and bacterial pathogens and release high levels of Type I interferons (IFN-I in response to infection. pDCs were shown to contribute to inflammatory responses in the steady state and in pathology. In atherosclerosis, pDCs are involved in priming vascular inflammation and atherogenesis through production of IFN-I and chemokines that attract inflammatory cells to inflamed sites. pDCs also contribute to the proinflammatory activation of effector T cells, cytotoxic T cells, and conventional DCs. However, tolerogenic populations of pDCs are found that suppress atherosclerosis-associated inflammation through down-regulation of function and proliferation of proinflammatory T cell subsets and induction of regulatory T cells with potent immunomodulatory properties. Notably, atheroprotective tolerogenic DCs could be induced by certain self-antigens or bacterial antigens that suggests for great therapeutic potential of these DCs for development of DC-based anti-atherogenic vaccines.

  1. Tolerance through Education: How Tolerogenic Dendritic Cells Shape Immunity

    Directory of Open Access Journals (Sweden)

    Matthias P. Domogalla

    2017-12-01

    Full Text Available Dendritic cells (DCs are central players in the initiation and control of responses, regulating the balance between tolerance and immunity. Tolerogenic DCs are essential in the maintenance of central and peripheral tolerance by induction of clonal T cell deletion and T cell anergy, inhibition of memory and effector T cell responses, and generation and activation of regulatory T cells. Therefore, tolerogenic DCs are promising candidates for specific cellular therapy of allergic and autoimmune diseases and for treatment of transplant rejection. Studies performed in rodents have demonstrated the efficacy and feasibility of tolerogenic DCs for tolerance induction in various inflammatory diseases. In the last years, numerous protocols for the generation of human monocyte-derived tolerogenic DCs have been established and some first phase I trials have been conducted in patients suffering from autoimmune disorders, demonstrating the safety and efficiency of this cell-based immunotherapy. This review gives an overview about methods and protocols for the generation of human tolerogenic DCs and their mechanisms of tolerance induction with the focus on interleukin-10-modulated DCs. In addition, we will discuss the prerequisites for optimal clinical grade tolerogenic DC subsets and results of clinical trials with tolerogenic DCs in autoimmune diseases.

  2. CD163 positive subsets of blood dendritic cells

    DEFF Research Database (Denmark)

    Maniecki, Maciej Bogdan; Møller, Holger Jon; Moestrup, Søren Kragh

    2006-01-01

    CD163 and CD91 are scavenging receptors with highly increased expression during the differentiation of monocytes into the anti-inflammatory macrophage phenotype. In addition, CD91 is expressed in monocyte-derived dendritic cells (MoDCs), where the receptor is suggested to be important...... for internalization of CD91-targeted antigens to be presented on the dendritic cell surface for T-cell stimulation. Despite their overlap in functionality, the expression of CD91 and CD163 has never been compared and the expression of CD163 in the monocyte-dendritic cell lineage is not yet characterized. CD163...... expression in dendritic cells (DCs) was investigated using multicolor flow cytometry in peripheral blood from 31 healthy donors and 15 HIV-1 patients in addition to umbilical cord blood from 5 newborn infants. Total RNA was isolated from MACS purified DCs and CD163 mRNA was determined with real-time reverse...

  3. Dendritic excitability modulates dendritic information processing in a purkinje cell model.

    Science.gov (United States)

    Coop, Allan D; Cornelis, Hugo; Santamaria, Fidel

    2010-01-01

    Using an electrophysiological compartmental model of a Purkinje cell we quantified the contribution of individual active dendritic currents to processing of synaptic activity from granule cells. We used mutual information as a measure to quantify the information from the total excitatory input current (I(Glu)) encoded in each dendritic current. In this context, each active current was considered an information channel. Our analyses showed that most of the information was encoded by the calcium (I(CaP)) and calcium activated potassium (I(Kc)) currents. Mutual information between I(Glu) and I(CaP) and I(Kc) was sensitive to different levels of excitatory and inhibitory synaptic activity that, at the same time, resulted in the same firing rate at the soma. Since dendritic excitability could be a mechanism to regulate information processing in neurons we quantified the changes in mutual information between I(Glu) and all Purkinje cell currents as a function of the density of dendritic Ca (g(CaP)) and Kca (g(Kc)) conductances. We extended our analysis to determine the window of temporal integration of I(Glu) by I(CaP) and I(Kc) as a function of channel density and synaptic activity. The window of information integration has a stronger dependence on increasing values of g(Kc) than on g(CaP), but at high levels of synaptic stimulation information integration is reduced to a few milliseconds. Overall, our results show that different dendritic conductances differentially encode synaptic activity and that dendritic excitability and the level of synaptic activity regulate the flow of information in dendrites.

  4. Commensal oral bacteria antigens prime human dendritic cells to induce Th1, Th2 or Treg differentiation.

    Science.gov (United States)

    Kopitar, A N; Ihan Hren, N; Ihan, A

    2006-02-01

    In various immunopathologic conditions, bacterial flora induce an immune response which results in inflammatory manifestations, e.g. periapical granuloma. Dendritic cells provide the main orchestration of specific immune responses. The aim of our study was to test the capacity of distinct oral bacterial antigens (prepared from Streptococcus mitis, Propionibacterium acnes, and Bacteroides spp.) to prime human dendritic cells for stimulation of the T-lymphocyte response. To assess the T-lymphocyte response, the expression of CD25, CD69, intracellular interferon gamma (cIFN-gamma), and intracellular interleukin 4 (cIL-4) was determined. Dendritic cells were prepared from leukocyte buffy coat from healthy blood donors. Monocytes were stimulated with IL-4 and GM-CSF and dendritic cells activated with bacterial lysates. Cell suspensions contained up to 90% dendritic cells, which represented 2-12% of the initial number of mononuclear cells. Lymphocyte subsets that developed in lymphocyte cultures after 1 week of stimulation were analyzed by flow cytometry. Dendritic cells, primed with antigens of Bacteroides fragilis have shown significantly higher activation and expression of intercellular IFN-gamma by T lymphocytes compared to negative controls. The dendritic cells primed with antigens of P. acnes had no effect on T-lymphocyte activation or cytokine production; instead they induced differentiation of T lymphocytes into CD25bright cells (regulatory T cells) with a potentially inhibitory effect on immune response. Dendritic cells primed with antigens of S. mitis induced increased expression of cIL-4. We conclude that commensal oral bacteria antigens prepared from B. fragilis, S. mitis, and P. acnes prime human dendritic cells to induce Th1, Th2, and T(reg) differentiation, respectively. This may advance our understanding of immunopathologic manifestations in the oral cavity and offer new possibilities for redirecting immune responses in mucosal vaccination.

  5. 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.

  6. Isolation of Human Skin Dendritic Cell Subsets.

    Science.gov (United States)

    Gunawan, Merry; Jardine, Laura; Haniffa, Muzlifah

    2016-01-01

    Dendritic cells (DCs) are specialized leukocytes with antigen-processing and antigen-presenting functions. DCs can be divided into distinct subsets by anatomical location, phenotype and function. In human, the two most accessible tissues to study leukocytes are peripheral blood and skin. DCs are rare in human peripheral blood (skin covering an average total surface area of 1.8 m(2) has approximately tenfold more DCs than the average 5 L of total blood volume (Wang et al., J Invest Dermatol 134:965-974, 2014). DCs migrate spontaneously from skin explants cultured ex vivo, which provide an easy method of cell isolation (Larsen et al., J Exp Med 172:1483-1493, 1990; Lenz et al., J Clin Invest 92:2587-2596, 1993; Nestle et al., J Immunol 151:6535-6545, 1993). These factors led to the extensive use of skin DCs as the "prototype" migratory DCs in human studies. In this chapter, we detail the protocols to isolate DCs and resident macrophages from human skin. We also provide a multiparameter flow cytometry gating strategy to identify human skin DCs and to distinguish them from macrophages.

  7. Breast Cancer Vaccines Based on Dendritic Cells and the Chemokines

    National Research Council Canada - National Science Library

    Mule, James

    1998-01-01

    The major objective of this project is to establish a new modality for the treatment of breast cancer that employs the combination of chemokine gene-modified fibroblasts with breast tumor-pulsed dendritic cells (DC...

  8. Breast Cancer Vaccines Based on Dendritic Cells and the Chemokines

    National Research Council Canada - National Science Library

    Mule, James

    1997-01-01

    The major objective of this project is to establish a new modality for the treatment of breast cancer that employs the combination of chemokine gene modified fibroblasts with breast tumor pulsed dendritic cells (DC...

  9. Dendritic cell-mediated T cell polarization

    NARCIS (Netherlands)

    de Jong, Esther C.; Smits, Hermelijn H.; Kapsenberg, Martien L.

    2005-01-01

    Effective defense against diverse types of micro-organisms that invade our body requires specialized classes of antigen-specific immune responses initiated and maintained by distinct subsets of effector CD4(+) T helper (Th) cells. Excessive or detrimental (e.g., autoimmune) responses by effector T

  10. Endothelial cell-derived microparticles induce plasmacytoid dendritic cell maturation: potential implications in inflammatory diseases.

    Science.gov (United States)

    Angelot, Fanny; Seillès, Estelle; Biichlé, Sabeha; Berda, Yael; Gaugler, Béatrice; Plumas, Joel; Chaperot, Laurence; Dignat-George, Françoise; Tiberghien, Pierre; Saas, Philippe; Garnache-Ottou, Francine

    2009-11-01

    Increased circulating endothelial microparticles, resulting from vascular endothelium dysfunction, and plasmacytoid dendritic cell activation are both encountered in common inflammatory disorders. The aim of our study was to determine whether interactions between endothelial microparticles and plasmacytoid dendritic cells could contribute to such pathologies. Microparticles generated from endothelial cell lines, platelets or activated T cells were incubated with human plasmacytoid dendritic cells sorted from healthy donor blood or with monocyte-derived dendritic cells. Dendritic cell maturation was evaluated by flow cytometry, cytokine secretion as well as naive T-cell activation and polarization. Labeled microparticles were also used to study cellular interactions. Endothelial microparticles induced plasmacytoid dendritic cell maturation. In contrast, conventional dendritic cells were resistant to endothelial microparticle-induced maturation. In addition to upregulation of co-stimulatory molecules, endothelial microparticle-matured plasmacytoid dendritic cells secreted inflammatory cytokines (interleukins 6 and 8, but no interferon-alpha) and also induced allogeneic naive CD4(+) T cells to proliferate and to produce type 1 cytokines such as interferon-gamma and tumor necrosis factor-alpha. Endothelial microparticle endocytosis by plasmacytoid dendritic cells appeared to be required for plasmacytoid dendritic cell maturation. Importantly, the ability of endothelial microparticles to induce plasmacytoid dendritic cells to mature was specific as microparticles derived from activated T cells or platelets (the major source of circulating microparticules in healthy subjects) did not induce such plasmacytoid dendritic cell maturation. Our data show that endothelial microparticles specifically induce plasmacytoid dendritic cell maturation and production of inflammatory cytokines. This novel activation pathway may be implicated in various inflammatory disorders and

  11. Novel immunomodulatory effects of adiponectin on dendritic cell functions.

    Science.gov (United States)

    Tsang, Julia Yuen Shan; Li, Daxu; Ho, Derek; Peng, Jiao; Xu, Aimin; Lamb, Jonathan; Chen, Yan; Tam, Paul Kwong Hang

    2011-05-01

    Adiponectin (ADN) is an adipocytokine with anti-inflammatory properties. Although it has been reported that ADN can inhibit the immunostimulatory function of monocytes and macrophages, little is known of its effect on dendritic cells (DC). Recent data suggest that ADN can regulate immune responses. DCs are uniquely specialised antigen presenting cells that play a central role in the initiation of immunity and tolerance. In this study, we have investigated the immuno- modulatory effects of ADN on DC functions. We found that ADN has only moderate effect on the differentiation of murine bone marrow (BM) derived DCs but altered the phenotype of DCs. The expression of major histocompatibilty complex class II (MHCII), CD80 and CD86 on ADN conditioned DCs (ADN-DCs) was lower than that on untreated cells. The production of IL-12p40 was also suppressed in ADN-DCs. Interestingly, ADN treated DCs showed an increase in the expression of the inhibitory molecule, programmed death-1 ligand (PDL-1) compared to untreated cells. In vitro co-culture of ADN-DCs with allogeneic T cells led to a decrease in T cell proliferation and reduction of IL-2 production. Concomitant with that, a higher percentage of CD4(+)CD25(+)Foxp3(+) regulatory T cells (Tregs) was detected in co-cultures of T cells and ADN-DCs. Blocking PD-1/PDL-1 pathway could partially restore T cell function. These findings suggest that the immunomodulatory effect of ADN on immune responses could be at least partially be mediated by its ability to alter DC function. The PD-1/PDL-1 pathway and the enhancement of Treg expansion are implicated in the immunomodulatory mechanisms. Copyright © 2010 Elsevier B.V. All rights reserved.

  12. A Model of Dendritic Cell Therapy for Melanoma

    Directory of Open Access Journals (Sweden)

    Ami eRadunskaya

    2013-03-01

    Full Text Available Dendritic cells are a promising immunotherapy tool for boosting an individual's antigen specific immune response to cancer. We develop a mathematical model using differential and delay-differential equations to describe the interactions between dendritic cells, effector-immune cells and tumor cells. We account for the trafficking of immune cells between lymph, blood, and tumor compartments. Our model reflects experimental results both for dendritic-cell trafficking and for immune suppression of tumor growth in mice. In addition, in silico experiments suggest more effective immunotherapy treatment protocols can be achieved by modifying dose location and schedule. A sensitivity analysis of the model reveals which patient-specific parameters have the greatest impact on treatment efficacy.

  13. Murid herpesvirus-4 exploits dendritic cells to infect B cells.

    Directory of Open Access Journals (Sweden)

    Miguel Gaspar

    2011-11-01

    Full Text Available Dendritic cells (DCs play a central role in initiating immune responses. Some persistent viruses infect DCs and can disrupt their functions in vitro. However, these viruses remain strongly immunogenic in vivo. Thus what role DC infection plays in the pathogenesis of persistent infections is unclear. Here we show that a persistent, B cell-tropic gamma-herpesvirus, Murid Herpesvirus-4 (MuHV-4, infects DCs early after host entry, before it establishes a substantial infection of B cells. DC-specific virus marking by cre-lox recombination revealed that a significant fraction of the virus latent in B cells had passed through a DC, and a virus attenuated for replication in DCs was impaired in B cell colonization. In vitro MuHV-4 dramatically altered the DC cytoskeleton, suggesting that it manipulates DC migration and shape in order to spread. MuHV-4 therefore uses DCs to colonize B cells.

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

    Directory of Open Access Journals (Sweden)

    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. Anti-regulatory T cells

    DEFF Research Database (Denmark)

    Andersen, Mads Hald

    2017-01-01

    responses to tumours or inhibiting autoimmunity development. However, recent studies report the discovery of self-reactive pro-inflammatory T cells—termed anti-regulatory T cells (anti-Tregs)—that target immune-suppressive cells. Thus, regulatory cells can now be defined as both cells that suppress immune...... reactions as well as effector cells that counteract the effects of suppressor cells and support immune reactions. Self-reactive anti-Tregs have been described that specifically recognize human leukocyte antigen-restricted epitopes derived from proteins that are normally expressed by regulatory immune cells......Our initial understanding of immune-regulatory cells was based on the discovery of suppressor cells that assure peripheral T-cell tolerance and promote immune homeostasis. Research has particularly focused on the importance of regulatory T cells (Tregs) for immune modulation, e.g. directing host...

  16. Controlling T-Cell Activation with Synthetic Dendritic Cells Using the Multivalency Effect

    NARCIS (Netherlands)

    Hammink, R.; Mandal, S.; Eggermont, L.J.; Nooteboom, M.; Willems, P.H.G.M.; Tel, J.; Rowan, A.E.; Figdor, C.G.; Blank, K.G.

    2017-01-01

    Artificial antigen-presenting cells (aAPCs) have recently gained a lot of attention. They efficiently activate T cells and serve as powerful replacements for dendritic cells in cancer immunotherapy. Focusing on a specific class of polymer-based aAPCs, so-called synthetic dendritic cells (sDCs), we

  17. The effects of renal transplantation on circulating dendritic cells

    NARCIS (Netherlands)

    D.A. Hesselink (Dennis); L.M.B. Vaessen (Leonard); W.C.J. Hop (Wim); W. Schoordijk-Verschoor (Wenda); J.N.M. IJzermans (Jan); C.C. Baan (Carla); W. Weimar (Willem)

    2005-01-01

    textabstractThe effects of immunosuppressive agents on T cell function have been well characterized but virtually nothing is known about the effects of renal transplantation on human dendritic cells (DCs). With the use of flow cytometry, we studied the kinetics of myeloid and plasmacytoid DCs in

  18. Unimpaired dendritic cell functions in MVP/LRP knockout mice.

    NARCIS (Netherlands)

    Mossink, MH; Groot, de J.; Zon, van A; Franzel-Luiten, E; Schoester, M.; Scheffer, G.L.; Sonneveld, P.; Scheper, R.J.; Wiemer, EA

    2003-01-01

    Dendritic cells (DCs) act as mobile sentinels of the immune system. By stimulating T lymphocytes, DCs are pivotal for the initiation of both T- and B-cell-mediated immune responses. Recently, ribonucleoprotein particles (vaults) were found to be involved in the development and/or function of human

  19. Tumor-Mediated Suppression of Dendritic Cell Vaccines

    National Research Council Canada - National Science Library

    Akporiaye, Emmanuel

    2004-01-01

    .... One of these factors is Transforming Growth Factor-beta (TGF-beta). TGF-beta is produced in large quantities by different types of cancer including breast cancer and inhibits the actions of several immune cells including dendritic cells (DC...

  20. Identification of human tissue cross-presenting dendritic cells

    OpenAIRE

    Haniffa, Muzlifah; Collin, Matthew; Ginhoux, Florent

    2013-01-01

    Dendritic cells (DCs) are a heterogeneous group of functionally specialized antigen-presenting cells. We recently characterized the human tissue cross-presenting DCs and aligned the human and mouse DC subsets. Our findings will facilitate the translation of murine DC studies to the human setting and aid the design of DC-based vaccine strategies for infection and cancer immunotherapy.

  1. Clinical application of dendritic cells in cancer vaccination therapy

    DEFF Research Database (Denmark)

    Svane, Inge Marie; Soot, Mette Line; Buus, Søren

    2003-01-01

    During the last decade use of dendritic cells (DC) has moved from murine and in vitro studies to clinical trials as adjuvant in cancer immunotherapy. Here they function as delivery vehicles for exogenous tumor antigens, promoting an efficient antigen presentation. The development of protocols...... for large-scale generation of dendritic cells for clinical applications has made possible phase I/II studies designed to analyze the toxicity, feasibility and efficacy of this approach. In clinical trials, DC-based vaccination of patients with advanced cancer has in many cases led to immunity...

  2. Blastic plasmacytoid dendritic cell neoplasm with absolute monocytosis at presentation

    Directory of Open Access Journals (Sweden)

    Jaworski JM

    2015-02-01

    Full Text Available Joseph M Jaworski,1,2 Vanlila K Swami,1 Rebecca C Heintzelman,1 Carrie A Cusack,3 Christina L Chung,3 Jeremy Peck,3 Matthew Fanelli,3 Micheal Styler,4 Sanaa Rizk,4 J Steve Hou1 1Department of Pathology and Laboratory Medicine, Hahnemann University Hospital/Drexel University College of Medicine, Philadelphia, PA, USA; 2Department of Pathology, Mercy Fitzgerald Hospital, Darby, PA, USA; 3Department of Dermatology, Hahnemann University Hospital/Drexel University College of Medicine, Philadelphia, PA, USA; 4Department of Hematology/Oncology, Hahnemann University Hospital/Drexel University College of Medicine, Philadelphia, PA, USA Abstract: Blastic plasmacytoid dendritic cell neoplasm is an uncommon malignancy derived from precursors of plasmacytoid dendritic cells. Nearly all patients present initially with cutaneous manifestations, with many having extracutaneous disease additionally. While response to chemotherapy initially is effective, relapse occurs in most, with a leukemic phase ultimately developing. The prognosis is dismal. While most of the clinical and pathologic features are well described, the association and possible prognostic significance between peripheral blood absolute monocytosis (>1.0 K/µL and blastic plasmacytoid dendritic cell neoplasm have not been reported. We report a case of a 68-year-old man who presented with a rash for 4–5 months. On physical examination, there were multiple, dull-pink, indurated plaques on the trunk and extremities. Complete blood count revealed thrombocytopenia, absolute monocytosis of 1.7 K/µL, and a negative flow cytometry study. Biopsy of an abdominal lesion revealed typical features of blastic plasmacytoid dendritic cell neoplasm. Patients having both hematologic and nonhematologic malignancies have an increased incidence of absolute monocytosis. Recent studies examining Hodgkin and non-Hodgkin lymphoma patients have suggested that this is a negative prognostic factor. The association between

  3. Increased level of both CD4+FOXP3+ regulatory T cells and CD14+HLA-DR⁻/low myeloid-derived suppressor cells and decreased level of dendritic cells in patients with multiple myeloma

    DEFF Research Database (Denmark)

    Brimnes, Marie Klinge; Vangsted, Annette Juul; Meldgaard Knudsen, Lene

    2010-01-01

    +FOXP3+ Treg cells was increased in patients at diagnosis and not in patients in remission or with MGUS. Also, Treg cells from patients with MM were functionally intact as they were able to inhibit proliferation of both CD4 and CD8 T cells. Finally, we observed an increase in the proportion of CD14+HLA-DR...... as a consequence of the disease....

  4. Equine dendritic cells generated with horse serum have enhanced functionality in comparison to dendritic cells generated with fetal bovine serum.

    Science.gov (United States)

    Ziegler, Anja; Everett, Helen; Hamza, Eman; Garbani, Mattia; Gerber, Vinzenz; Marti, Eliane; Steinbach, Falko

    2016-11-15

    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. Currently, the gold standard protocol for generating dendritic cells from monocytes across various species relies upon a combination of GM-CSF and IL-4 added to cell culture medium which is supplemented with FBS. The aim of this study was to substitute FBS with heterologous horse serum. For this purpose, equine monocyte-derived dendritic cells (eqMoDC) were generated in the presence of horse serum or FBS and analysed for the effect on morphology, phenotype and immunological properties. Changes in the expression of phenotypic markers (CD14, CD86, CD206) were assessed during dendritic cell maturation by flow cytometry. To obtain a more complete picture of the eqMoDC differentiation and assess possible differences between FBS- and horse serum-driven cultures, a transcriptomic microarray analysis was performed. Lastly, immature eqMoDC were primed with a primary antigen (ovalbumin) or a recall antigen (tetanus toxoid) and, after maturation, were co-cultured with freshly isolated autologous CD5 + T lymphocytes to assess their T cell stimulatory capacity. The microarray analysis demonstrated that eqMoDC generated with horse serum were indistinguishable from those generated with FBS. However, eqMoDC incubated with horse serum-supplemented medium exhibited a more characteristic dendritic cell morphology during differentiation from monocytes. A significant increase in cell viability was also observed in eqMoDC cultured with horse serum. Furthermore, eqMoDC generated in the presence of horse serum

  5. What on "irf" is this gene 4? Irf4 transcription-factor-dependent dendritic cells are required for T helper 2 cell responses in murine skin.

    Science.gov (United States)

    Flutter, Barry; Nestle, Frank O

    2013-10-17

    Interferon regulatory factors play an important role in the transcriptional regulation of immunity. In this issue of Immunity, Kumamoto et al. (2013) and Gao et al. (2013) identify an Irf4-dependent migratory dendritic cell subset required for T helper 2 cell polarization following cutaneous challenge. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. DC-SIGN, a C-type lectin on dendritic cells that unveils many aspects of dendritic cell biology

    NARCIS (Netherlands)

    Geijtenbeek, Teunis B. H.; Engering, Anneke; van Kooyk, Yvette

    2002-01-01

    Dendritic cells (DC) are present in essentially every tissue where they operate at the interface of innate and acquired immunity by recognizing pathogens and presenting pathogen-derived peptides to T cells. It is becoming clear that not all C-type lectins on DC serve as antigen receptors recognizing

  7. Transcriptional Changes during Naturally Acquired Zika Virus Infection Render Dendritic Cells Highly Conducive to Viral Replication.

    Science.gov (United States)

    Sun, Xiaoming; Hua, Stephane; Chen, Hsiao-Rong; Ouyang, Zhengyu; Einkauf, Kevin; Tse, Samantha; Ard, Kevin; Ciaranello, Andrea; Yawetz, Sigal; Sax, Paul; Rosenberg, Eric S; Lichterfeld, Mathias; Yu, Xu G

    2017-12-19

    Although dendritic cells are among the human cell population best equipped for cell-intrinsic antiviral immune defense, they seem highly susceptible to infection with the Zika virus (ZIKV). Using highly purified myeloid dendritic cells isolated from individuals with naturally acquired acute infection, we here show that ZIKV induces profound perturbations of transcriptional signatures relative to healthy donors. Interestingly, we noted a remarkable downregulation of antiviral interferon-stimulated genes and innate immune sensors, suggesting that ZIKV can actively suppress interferon-dependent immune responses. In contrast, several host factors known to support ZIKV infection were strongly upregulated during natural ZIKV infection; these transcripts included AXL, the main entry receptor for ZIKV; SOCS3, a negative regulator of ISG expression; and IDO-1, a recognized inducer of regulatorycell responses. Thus, during in vivo infection, ZIKV can transform the transcriptome of dendritic cells in favor of the virus to render these cells highly conducive to ZIKV infection. Published by Elsevier Inc.

  8. T cell motility as modulator of interactions with dendritic cells

    Directory of Open Access Journals (Sweden)

    Jens Volker Stein

    2015-11-01

    Full Text Available It is well established that the balance of costimulatory and inhibitory signals during interactions with dendritic cells (DCs determines T cell transition from a naïve to an activated or tolerant/anergic status. While many of these molecular interactions are well reproduced in reductionist in vitro assays, the highly dynamic motility of naïve T cells in lymphoid tissue acts as an additional lever to fine-tune their activation threshold. T cell detachment from DCs providing suboptimal stimulation allows them to search for DCs with higher levels of stimulatory signals, while storing a transient memory of short encounters. In turn, adhesion of weakly reactive T cells to DCs presenting pMHC with low affinity is prevented by lipid mediators. Finally, controlled recruitment of CD8+ T cells to cognate DC – CD4+ T cell clusters shapes memory T cell formation and the quality of the immune response. Dynamic physiological lymphocyte motility therefore constitutes a mechanism to mitigate low avidity T cell activation and to improve the search for optimal DCs, while contributing to peripheral tolerance induction in the absence of inflammation.

  9. File list: InP.Bld.05.AllAg.Dendritic_Cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

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    Lifescience Database Archive (English)

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  12. File list: Unc.Bld.20.AllAg.Dendritic_Cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.Bld.20.AllAg.Dendritic_Cells hg19 Unclassified Blood Dendritic Cells SRX818200,...189,SRX818202,SRX818182,SRX818195,SRX818196,SRX818181 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Unc.Bld.20.AllAg.Dendritic_Cells.bed ...

  13. Blastic plasmacytoid dendritic cell neoplasm: report of two pediatric cases.

    Science.gov (United States)

    Dharmani, Preeti Ashok; Mittal, Neha Manish; Subramanian, P G; Galani, Komal; Badrinath, Yajamanam; Amare, Pratibha; Gujral, Sumeet

    2015-01-01

    Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare subtype of acute leukemia that typically follows a highly aggressive clinical course in adults, whereas experience in children with this disease is very limited. We report cases of two children in whom bone marrow showed infiltration by large atypical monocytoid 'blast-like' cells which on immunophenotyping expressed CD4, CD56, HLA-DR and CD33 while were negative for CD34 other T-cell, B-cell and myeloid markers. The differential diagnoses considered were AML, T/NK-cell leukemia and acute undifferentiated leukemia. Additional markers CD303/BDCA-2 and CD123 which are recently validated plasmacytoid dendritic cell markers were done which helped us clinch the diagnosis of this rare neoplasm. An accurate diagnosis of BPDCN is essential in order to provide prompt treatment. Due to its rarity and only recent recognition as a distinct clinicopathological entity, no standardized therapeutic approach has been established for BPDCN.

  14. Modulation of cytokine production profiles in splenic dendritic cells ...

    African Journals Online (AJOL)

    We examined the role of splenic dendritic cells in immune response to Toxoplasma gondii infection in SAG1 (P30+) transgenic mice by investigating the kinetics of intracellular cytokines expression of IL-4, IL-10, IL-12 and IFN-γ by intracellular cytokine staining (ICS) using flow cytometry, and compared the results to those of ...

  15. Circulating dendritic cells in pediatric patients with nephrotic syndrome

    African Journals Online (AJOL)

    Background: Dendritic cells (DCs) represent one of the most extensively studied topics in immunology, because of their central role in the induction and regulation of adaptive immunity, and because of their therapeutic potential for manipulating immune responses. Objectives: To evaluate circulating DC levels in pediatric ...

  16. Genetically engineered dendritic cell-based cancer vaccines

    Czech Academy of Sciences Publication Activity Database

    Bubeník, Jan

    2001-01-01

    Roč. 18, č. 3 (2001), s. 475-478 ISSN 1019-6439 R&D Projects: GA MZd NC5526 Keywords : dendritic cell s * tumour vaccines Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.330, year: 2001

  17. Genetically modified dendritic cell-based cancer vaccines

    Czech Academy of Sciences Publication Activity Database

    Bubeník, Jan

    2001-01-01

    Roč. 47, č. 5 (2001), s. 153-155 ISSN 0015-5500 R&D Projects: GA MZd NC5526 Keywords : dendritic cell s * cancer vaccines Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.519, year: 2001

  18. Blastic Plasmacytoid Dendritic Cell Leukemia in a Black Malian

    African Journals Online (AJOL)

    2017-06-28

    Jun 28, 2017 ... BPDCN in Mali. KEYWORDS: Acute Leukemia, black african, dendritic cell, Mali ... myeloid neoplasm by the 2008 world health organization classification of .... There are many standardized treatment regimens, and many protocols with ... leukemia chemotherapy regimen[7,11] or chronic leukemia treatment ...

  19. Interferon-α induces marked alterations in circulating regulatory T cells, NK cell subsets, and dendritic cells in patients with JAK2V617F-positive essential thrombocythemia and polycythemia vera

    DEFF Research Database (Denmark)

    Riley, Caroline H; Brimnes, Marie K; Hansen, Morten

    2016-01-01

    Long-term therapy with IFN-α2 is associated with sustained major molecular remissions in JAK2-positive ET and PV. The efficacy of IFN-α2 may be partly mediated by modulation of immune cells, which was investigated in twenty patients with ET (n = 6) and PV (n = 14). The frequency of CD4+CD25+Foxp3...

  20. Chemokines: a new dendritic cell signal for T cell activation

    Directory of Open Access Journals (Sweden)

    Christoph A Thaiss

    2011-08-01

    Full Text Available Dendritic cells (DCs are the main inducers and regulators of cytotoxic T lymphocyte (CTL responses against viruses and tumors. One checkpoint to avoid misguided CTL activation, which might damage healthy cells of the body, is the necessity for multiple activation signals, involving both antigenic as well as additional signals that reflect the presence of pathogens. DCs provide both signals when activated by ligands of pattern recognition receptors and licensed by helper lymphocytes. Recently, it has been established that such T cell licensing can be facilitated by CD4+ T helper cells (classical licensing or by NKT cells (alternative licensing. Licensing regulates the DC/CTL cross-talk at multiple layers. Direct recruitment of CTLs through chemokines released by licensed DCs has recently emerged as a common theme and has a crucial impact on the efficiency of CTL responses. Here, we discuss recent advances in our understanding of DC licensing for cross-priming and implications for the temporal and spatial regulation underlying this process. Future vaccination strategies will benefit from a deeper insight into the mechanisms that govern CTL activation.

  1. Relative Contributions of B Cells and Dendritic Cells from Lupus-Prone Mice to CD4+ T Cell Polarization.

    Science.gov (United States)

    Choi, Seung-Chul; Xu, Zhiwei; Li, Wei; Yang, Hong; Roopenian, Derry C; Morse, Herbert C; Morel, Laurence

    2018-05-01

    Mouse models of lupus have shown that multiple immune cell types contribute to autoimmune disease. This study sought to investigate the involvement of B cells and dendritic cells in supporting the expansion of inflammatory and regulatory CD4 + T cells that are critical for lupus pathogenesis. We used lupus-prone B6.NZM2410.Sle1.Sle2.Sle3 (TC) and congenic C57BL/6J (B6) control mice to investigate how the genetic predisposition of these two cell types controls the activity of normal B6 T cells. Using an allogeneic in vitro assay, we showed that TC B1-a and conventional B cells expanded Th17 cells significantly more than their B6 counterparts. This expansion was dependent on CD86 and IL-6 expression and mapped to the Sle1 lupus-susceptibility locus. In vivo, TC B cells promoted greater differentiation of CD4 + T cells into Th1 and follicular helper T cells than did B6 B cells, but they limited the expansion of Foxp3 regulatory CD4 + T cells to a greater extent than did B6 B cells. Finally, when normal B6 CD4 + T cells were introduced into Rag1 -/- mice, TC myeloid/stromal cells caused their heightened activation, decreased Foxp3 regulatory CD4 + T cell differentiation, and increased renal infiltration of Th1 and Th17 cells in comparison with B6 myeloid/stromal cells. The results show that B cells from lupus mice amplify inflammatory CD4 + T cells in a nonredundant manner with myeloid/stromal cells. Copyright © 2018 by The American Association of Immunologists, Inc.

  2. Anti tumor vaccination with hybrid dendritic-tumour cells

    International Nuclear Information System (INIS)

    Barbuto, Jose Alexandre M.; Neves, Andreia R.; Ensina, Luis Felipe C.; Anselmo, Luciene B.

    2005-01-01

    Dendritic cells are the most potent antigen-presenting cells, and the possibility of their use for cancer vaccination has renewed the interest in this therapeutic modality. Nevertheless, the ideal immunization protocol with these cells has not been described yet. In this paper we describe the preliminary results of a protocol using autologous tumor and allogeneic dendritic hybrid cell vaccination every 6 weeks, for metastatic melanoma and renal cell carcinoma (RCC) patients. Thirty-five patients were enrolled between March 2001 and March 2003. Though all patients included presented with large tumor burdens and progressive diseases, 71% of them experienced stability after vaccination, with durations up to 19 months. Among RCC patients 3/22 (14%) presented objective responses. The median time to progression was 4 months for melanoma and 5.7 months for RCC patients; no significant untoward effects were noted. Furthermore, immune function, as evaluated by cutaneous delayed-type hypersensitivity reactions to recall antigens and by peripheral blood proliferative responses to tumor-specific and nonspecific stimuli, presented a clear tendency to recover in vaccinated patients. These data indicate that dendritic cell-tumor cell hybrid vaccination affects the natural history of advanced cancer and provide support for its study in less advanced patients, who should, more likely, benefit even more from this approach. (author)

  3. Signaling network of dendritic cells in response to pathogens: a community-input supported knowledgebase

    Directory of Open Access Journals (Sweden)

    Nudelman Irina

    2010-10-01

    Full Text Available Abstract Background Dendritic cells are antigen-presenting cells that play an essential role in linking the innate and adaptive immune systems. Much research has focused on the signaling pathways triggered upon infection of dendritic cells by various pathogens. The high level of activity in the field makes it desirable to have a pathway-based resource to access the information in the literature. Current pathway diagrams lack either comprehensiveness, or an open-access editorial interface. Hence, there is a need for a dependable, expertly curated knowledgebase that integrates this information into a map of signaling networks. Description We have built a detailed diagram of the dendritic cell signaling network, with the goal of providing researchers with a valuable resource and a facile method for community input. Network construction has relied on comprehensive review of the literature and regular updates. The diagram includes detailed depictions of pathways activated downstream of different pathogen recognition receptors such as Toll-like receptors, retinoic acid-inducible gene-I-like receptors, C-type lectin receptors and nucleotide-binding oligomerization domain-like receptors. Initially assembled using CellDesigner software, it provides an annotated graphical representation of interactions stored in Systems Biology Mark-up Language. The network, which comprises 249 nodes and 213 edges, has been web-published through the Biological Pathway Publisher software suite. Nodes are annotated with PubMed references and gene-related information, and linked to a public wiki, providing a discussion forum for updates and corrections. To gain more insight into regulatory patterns of dendritic cell signaling, we analyzed the network using graph-theory methods: bifan, feedforward and multi-input convergence motifs were enriched. This emphasis on activating control mechanisms is consonant with a network that subserves persistent and coordinated responses to

  4. Signaling network of dendritic cells in response to pathogens: a community-input supported knowledgebase.

    Science.gov (United States)

    Patil, Sonali; Pincas, Hanna; Seto, Jeremy; Nudelman, German; Nudelman, Irina; Sealfon, Stuart C

    2010-10-07

    Dendritic cells are antigen-presenting cells that play an essential role in linking the innate and adaptive immune systems. Much research has focused on the signaling pathways triggered upon infection of dendritic cells by various pathogens. The high level of activity in the field makes it desirable to have a pathway-based resource to access the information in the literature. Current pathway diagrams lack either comprehensiveness, or an open-access editorial interface. Hence, there is a need for a dependable, expertly curated knowledgebase that integrates this information into a map of signaling networks. We have built a detailed diagram of the dendritic cell signaling network, with the goal of providing researchers with a valuable resource and a facile method for community input. Network construction has relied on comprehensive review of the literature and regular updates. The diagram includes detailed depictions of pathways activated downstream of different pathogen recognition receptors such as Toll-like receptors, retinoic acid-inducible gene-I-like receptors, C-type lectin receptors and nucleotide-binding oligomerization domain-like receptors. Initially assembled using CellDesigner software, it provides an annotated graphical representation of interactions stored in Systems Biology Mark-up Language. The network, which comprises 249 nodes and 213 edges, has been web-published through the Biological Pathway Publisher software suite. Nodes are annotated with PubMed references and gene-related information, and linked to a public wiki, providing a discussion forum for updates and corrections. To gain more insight into regulatory patterns of dendritic cell signaling, we analyzed the network using graph-theory methods: bifan, feedforward and multi-input convergence motifs were enriched. This emphasis on activating control mechanisms is consonant with a network that subserves persistent and coordinated responses to pathogen detection. This map represents a navigable

  5. Dendritic Kv3.3 potassium channels in cerebellar purkinje cells regulate generation and spatial dynamics of dendritic Ca2+ spikes.

    Science.gov (United States)

    Zagha, Edward; Manita, Satoshi; Ross, William N; Rudy, Bernardo

    2010-06-01

    Purkinje cell dendrites are excitable structures with intrinsic and synaptic conductances contributing to the generation and propagation of electrical activity. Voltage-gated potassium channel subunit Kv3.3 is expressed in the distal dendrites of Purkinje cells. However, the functional relevance of this dendritic distribution is not understood. Moreover, mutations in Kv3.3 cause movement disorders in mice and cerebellar atrophy and ataxia in humans, emphasizing the importance of understanding the role of these channels. In this study, we explore functional implications of this dendritic channel expression and compare Purkinje cell dendritic excitability in wild-type and Kv3.3 knockout mice. We demonstrate enhanced excitability of Purkinje cell dendrites in Kv3.3 knockout mice, despite normal resting membrane properties. Combined data from local application pharmacology, voltage clamp analysis of ionic currents, and assessment of dendritic Ca(2+) spike threshold in Purkinje cells suggest a role for Kv3.3 channels in opposing Ca(2+) spike initiation. To study the physiological relevance of altered dendritic excitability, we measured [Ca(2+)](i) changes throughout the dendritic tree in response to climbing fiber activation. Ca(2+) signals were specifically enhanced in distal dendrites of Kv3.3 knockout Purkinje cells, suggesting a role for dendritic Kv3.3 channels in regulating propagation of electrical activity and Ca(2+) influx in distal dendrites. These findings characterize unique roles of Kv3.3 channels in dendrites, with implications for synaptic integration, plasticity, and human disease.

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

    Directory of Open Access Journals (Sweden)

    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

  7. Interaction between dendritic cells and natural killer cells during pregnancy in mice.

    Science.gov (United States)

    Blois, Sandra M; Barrientos, Gabriela; Garcia, Mariana G; Orsal, Arif S; Tometten, Mareike; Cordo-Russo, Rosalia I; Klapp, Burghard F; Santoni, Angela; Fernández, Nelson; Terness, Peter; Arck, Petra C

    2008-07-01

    A complex regulation of innate and adaptive immune responses at the maternal fetal interface promotes tolerance of trophoblast cells carrying paternally derived antigens. Such regulatory functions involve uterine dendritic cells (uDC) and natural killer (uNK) cells. The existence of a NK and DC "cross talk" has been revealed in various experimental settings; its biological significance ranging from cooperative stimulation to cell lysis. Little is known about the presence or role of NK and DC cross talk at the maternal fetal interface. The present study shows that mouse NK and DC interactions are subject to modulation by trophoblast cells in vitro. This interaction promotes a tolerogenic microenvironment characterized by downregulation of the expression of activation markers on uNK cells and uDC and dominance of Th2 cytokines. NK and DC interactions would also influence uterine cell proliferation and this process would be strongly modulated by trophoblast-derived signals. Indeed; while low proliferation rates were observed upon regular coculture allowing direct contact between uterine cells and trophoblasts, incubation in a transwell culture system markedly increased uterine cell proliferation suggesting that soluble factors are key mediators in the molecular "dialog" between the mother and the conceptus during the establishment of mouse pregnancy. Our data further reveal that the regulatory functions of trophoblast cells associated with tolerance induction are impaired in high abortion murine matings. Interestingly, we observed that secretion of interleukin-12p70 by uDC is dramatically abrogated in the presence of uNK cells. Taken together, our results provide the first evidence that a delicate balance of interactions involving NK cells, DC, and trophoblasts at the mouse maternal fetal interface supports a successful pregnancy outcome.

  8. Evaluation of two different dendritic cell preparations with BCG reactivity

    Directory of Open Access Journals (Sweden)

    Fol Marek

    2016-01-01

    Full Text Available Dendritic cells (DCs play a key-role in the immune response against intracellular bacterial pathogens, including mycobacteria. Monocyte-derived dendritic cells (MoDCs are considered to behave as inflammatory cell populations. Different immunomagnetic methods (positive and negative can be used to purify monocytes before their in vitro differentiation and their culture behavior can be expected to be different. In this study we evaluated the reactivity of two dendritic cell populations towards the Bacillus Calmette-Guérin (BCG antigen. Monocytes were obtained from the blood of healthy donors, using positive and negative immunomagnetic separation methods. The expression of DC-SIGN, CD86, CD80, HLA-DR and CD40 on MoDCs was estimated by flow cytometry. The level of IL-12p70, IL-10 and TNF-α was measured by ELISA. Neither of the tested methods affected the surface marker expression of DCs. No significant alteration in immunological response, measured by cytokine production, was noted either. After BCG stimulation, the absence of IL-12, but the IL-23 production was observed in both cell preparations. Positive and negative magnetic separation methods are effective techniques to optimize the preparation of monocytes as the source of MoDCs for potential clinical application.

  9. 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...

  10. mRNA-transfected dendritic cell vaccine in combination with metronomic cyclophosphamide as treatment for patients with advanced malignant melanoma

    DEFF Research Database (Denmark)

    Borch, Troels Holz; Engell-Noerregaard, Lotte; Iversen, Trine Zeeberg

    2016-01-01

    Introduction: Vaccination with dendritic cells (DCs) has generally not fulfilled its promise in cancer immunotherapy due to ineffective translation of immune responses into clinical responses. A proposed reason for this is intrinsic immune regulatory mechanisms, such as regulatory T cells (Tregs......th vaccines. Immune monitoring consisted of IFNγ ELISpot assay, proliferation assay, and flow cytometry for enumeration of immune cell subsets.  Results: Toxicity was manageable. Eighteen patients were evaluable after six cycles. Of these, nine patients had progressive disease as best response...

  11. Capacity of Lung Stroma to Educate Dendritic Cells Inhibiting Mycobacteria-Specific T-Cell Response Depends upon Genetic Susceptibility to Tuberculosis

    OpenAIRE

    Kapina, Marina A.; Rubakova, Elvira I.; Majorov, Konstantin B.; Logunova, Nadezhda N.; Apt, Alexander S.

    2013-01-01

    The balance between activation and inhibition of local immune responses in affected tissues during prolonged chronic infections is important for host protection. There is ample evidence that regulatory, tolerogenic dendritic cells (DC) are developed and present in tissues and inhibit overwhelming inflammatory reactions. Also, it was firmly established that stromal microenvironment of many organs is able to induce development of immature regulatory DC (DCreg), an essential element of a general...

  12. Intestinal dendritic cells in the regulation of mucosal immunity

    DEFF Research Database (Denmark)

    Bekiaris, Vasileios; Persson, Emma K.; Agace, William Winston

    2014-01-01

    immune cells within the mucosa must suitably respond to maintain intestinal integrity, while also providing the ability to mount effective immune responses to potential pathogens. Dendritic cells (DCs) are sentinel immune cells that play a central role in the initiation and differentiation of adaptive....... The recognition that dietary nutrients and microbial communities in the intestine influence both mucosal and systemic immune cell development and function as well as immune-mediated disease has led to an explosion of literature in mucosal immunology in recent years and a growing interest in the functionality...

  13. 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.

  14. Development of a replication-competent lentivirus assay for dendritic cell-targeting lentiviral vectors

    Directory of Open Access Journals (Sweden)

    Daniel C Farley

    Full Text Available It is a current regulatory requirement to demonstrate absence of detectable replication-competent lentivirus (RCL in lentiviral vector products prior to use in clinical trials. Immune Design previously described an HIV-1-based integration-deficient lentiviral vector for use in cancer immunotherapy (VP02. VP02 is enveloped with E1001, a modified Sindbis virus glycoprotein which targets dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN expressed on dendritic cells in vivo. Vector enveloped with E1001 does not transduce T-cell lines used in standard HIV-1-based RCL assays, making current RCL testing formats unsuitable for testing VP02. We therefore developed a novel assay to test for RCL in clinical lots of VP02. This assay, which utilizes a murine leukemia positive control virus and a 293F cell line expressing the E1001 receptor DC-SIGN, meets a series of evaluation criteria defined in collaboration with US regulatory authorities and demonstrates the ability of the assay format to amplify and detect a hypothetical RCL derived from VP02 vector components. This assay was qualified and used to test six independent GMP production lots of VP02, in which no RCL was detected. We propose that the evaluation criteria used to rationally design this novel method should be considered when developing an RCL assay for any lentiviral vector.

  15. Molecular signatures of maturing dendritic cells: implications for testing the quality of dendritic cell therapies

    Directory of Open Access Journals (Sweden)

    Wang Ena

    2010-01-01

    Full Text Available Abstract Background Dendritic cells (DCs are often produced by granulocyte-macrophage colony-stimulating factor (GM-CSF and interleukin-4 (IL-4 stimulation of monocytes. To improve the effectiveness of DC adoptive immune cancer therapy, many different agents have been used to mature DCs. We analyzed the kinetics of DC maturation by lipopolysaccharide (LPS and interferon-γ (IFN-γ induction in order to characterize the usefulness of mature DCs (mDCs for immune therapy and to identify biomarkers for assessing the quality of mDCs. Methods Peripheral blood mononuclear cells were collected from 6 healthy subjects by apheresis, monocytes were isolated by elutriation, and immature DCs (iDCs were produced by 3 days of culture with GM-CSF and IL-4. The iDCs were sampled after 4, 8 and 24 hours in culture with LPS and IFN-γ and were then assessed by flow cytometry, ELISA, and global gene and microRNA (miRNA expression analysis. Results After 24 hours of LPS and IFN-γ stimulation, DC surface expression of CD80, CD83, CD86, and HLA Class II antigens were up-regulated. Th1 attractant genes such as CXCL9, CXCL10, CXCL11 and CCL5 were up-regulated during maturation but not Treg attractants such as CCL22 and CXCL12. The expression of classical mDC biomarker genes CD83, CCR7, CCL5, CCL8, SOD2, MT2A, OASL, GBP1 and HES4 were up-regulated throughout maturation while MTIB, MTIE, MTIG, MTIH, GADD45A and LAMP3 were only up-regulated late in maturation. The expression of miR-155 was up-regulated 8-fold in mDCs. Conclusion DCs, matured with LPS and IFN-γ, were characterized by increased levels of Th1 attractants as opposed to Treg attractants and may be particularly effective for adoptive immune cancer therapy.

  16. Dendritic thickness: a morphometric parameter to classify mouse retinal ganglion cells

    Directory of Open Access Journals (Sweden)

    L.D. Loopuijt

    2007-10-01

    Full Text Available To study the dendritic morphology of retinal ganglion cells in wild-type mice we intracellularly injected these cells with Lucifer yellow in an in vitro preparation of the retina. Subsequently, quantified values of dendritic thickness, number of branching points and level of stratification of 73 Lucifer yellow-filled ganglion cells were analyzed by statistical methods, resulting in a classification into 9 groups. The variables dendritic thickness, number of branching points per cell and level of stratification were independent of each other. Number of branching points and level of stratification were independent of eccentricity, whereas dendritic thickness was positively dependent (r = 0.37 on it. The frequency distribution of dendritic thickness tended to be multimodal, indicating the presence of at least two cell populations composed of neurons with dendritic diameters either smaller or larger than 1.8 µm ("thin" or "thick" dendrites, respectively. Three cells (4.5% were bistratified, having thick dendrites, and the others (95.5% were monostratified. Using k-means cluster analysis, monostratified cells with either thin or thick dendrites were further subdivided according to level of stratification and number of branching points: cells with thin dendrites were divided into 2 groups with outer stratification (0-40% and 2 groups with inner (50-100% stratification, whereas cells with thick dendrites were divided into one group with outer and 3 groups with inner stratification. We postulate, that one group of cells with thin dendrites resembles cat ß-cells, whereas one group of cells with thick dendrites includes cells that resemble cat a-cells.

  17. 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.

  18. Maturational steps of bone marrow-derived dendritic murine epidermal cells. Phenotypic and functional studies on Langerhans cells and Thy-1+ dendritic epidermal cells in the perinatal period.

    Science.gov (United States)

    Elbe, A; Tschachler, E; Steiner, G; Binder, A; Wolff, K; Stingl, G

    1989-10-15

    The adult murine epidermis harbors two separate CD45+ bone marrow (BM)-derived dendritic cell systems, i.e., Ia+, ADPase+, Thy-1-, CD3- Langerhans cells (LC) and Ia-, ADPase-, Thy-1+, CD3+ dendritic epidermal T cells (DETC). To clarify whether the maturation of these cells from their ill-defined precursors is already accomplished before their entry into the epidermis or, alternatively, whether a specific epidermal milieu is required for the expression of their antigenic determinants, we studied the ontogeny of CD45+ epidermal cells (EC). In the fetal life, there exists a considerable number of CD45+, Ia-, ADPase+ dendritic epidermal cells. When cultured, these cells become Ia+ and, in parallel, acquire the potential of stimulating allogeneic T cell proliferation. These results imply that CD45+, Ia-, ADPase+ fetal dendritic epidermal cells are immature LC precursors and suggest that the epidermis plays a decisive role in LC maturation. The day 17 fetal epidermis also contains a small population of CD45+, Thy-1+, ADPase-, CD3- round cells. Over the course of 2 to 3 wk, they are slowly replaced by an ever increasing number of round and, finally, dendritic CD45+, Thy-1+, CD3+ EC. Thus, CD45+, Thy-1+, ADPase-, CD3- fetal EC may either be DETC precursors or, alternatively, may represent a distinctive cell system of unknown maturation potential. According to this latter theory, these cells would be eventually outnumbered by newly immigrating CD45+, Thy-1+, CD3+ T cells--the actual DETC.

  19. Novel Vectors for Dendritic Cell Transduction

    National Research Council Canada - National Science Library

    Strong, Teresa

    2003-01-01

    .... Polynucleotide vaccines have several advantages compared to traditional vaccines including the ability to elicit antigen-specific T cells, inherent immunogenicity, ability to modify the encoded...

  20. Targeting dendritic cells in vivo for cancer therapy

    Directory of Open Access Journals (Sweden)

    Irina eCaminschi

    2012-02-01

    Full Text Available Monoclonal antibodies that recognise cell surface molecules have been used deliver antigenic cargo to dendritic cells (DC for induction of immune responses. The encouraging anti-tumour immunity elicited using this immunisation strategy suggests its suitability for clinical trials. This review discusses the complex network of DC, the functional specialisation of DC-subsets, the immunological outcomes of targeting different DC-subsets and their cell surface receptors, and the requirements for the induction of effective anti-tumour immunity. Finally, we review preclinical experiments and the progress towards targeting human DC in vivo.

  1. Phenotypic and functional analysis of CD1a+ dendritic cells from cats chronically infected with feline immunodeficiency virus.

    Science.gov (United States)

    Zhang, Lin; Reckling, Stacie; Dean, Gregg A

    2015-10-01

    Numerous studies suggest dendritic cell (DC) dysfunction is central to the dysregulated immune response during HIV infection; however, in vivo studies are lacking. In the present study we used feline immunodeficiency virus (FIV) infection of cats as a model for HIV-1 infection to assess the maturation and function of dendritic cells, in vivo and in vitro. We compared CD1a+ DC migration, surface phenotype, endocytosis, mixed leukocyte reaction (MLR) and regulatory T cell (Treg) phenotype induction by CD1a+ cells isolated from lymph nodes of FIV-infected and control cats. Results showed that resident CD1a+ DC in lymph nodes of chronically FIV-infected cats are phenotypically mature, can stimulate normal primary T cell proliferation, override Treg suppression and do not skew toward Treg induction. In contrast, FIV infection had deleterious effects on antigen presentation and migratory capacity of CD1a+ cells in tissues. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Impact of HBeAg on the maturation and function of dendritic cells.

    Science.gov (United States)

    Lan, Songsong; Wu, Lecan; Wang, Xiuyan; Wu, Jinming; Lin, Xianfan; Wu, Wenzhi; Huang, Zhiming

    2016-05-01

    HBV infection typically leads to chronic hepatitis in newborns and some adults with weakened immune systems. The mechanisms by which virus escapes immunity remain undefined. Regulatory dendritic cells (DCregs) contributing to immune escape have been described. We wondered whether or not HBeAg as an immunomodulatory protein could induce DCreg which might subsequently result into HBV persistence. The immunophenotyping, T-cell activation and cytokine production were analyzed in HBeAg-treated DCs from normal or cyclophosphamide (Cy)-induced immunocompromised mice. HBeAg tended to promote bone marrow derived DCs (BMDCs) from Cy-treated mice into CD11b(high)PIR-B(+) regulatory DCs exhibiting the lowest T-cell stimulatory capacity and interleukin (IL)-12p70 production compared with controls. Neutralization of IL-10 significantly inhibited the regulatory effect of these DCs on T-cell stimulation of mature DCs. After lipopolysaccharides (LPS) stimulation, marked phosphorylation of Akt was detected in HBeAg treated DCs from immunocompromised mice. Blocking the PI3K-Akt pathway by LY294002 led to an enhancement of IL-12 production. PI3K signalling pathway appears to be involved in the decreased IL-12 secretion by HBeAg treated DCs. These findings suggest that HBeAg may program the generation of a new DC subset with regulatory capacity under the condition of immunosuppression, which may presumably contribute to the persistent HBV infection. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. Role of Natural Killer and Dendritic Cell Crosstalk in Immunomodulation by Commensal Bacteria Probiotics

    Directory of Open Access Journals (Sweden)

    Valeria Rizzello

    2011-01-01

    Full Text Available A cooperative dialogue between natural killer (NK cells and dendritic cells (DCs has been elucidated in the last years. They help each other to acquire their complete functions, both in the periphery and in the secondary lymphoid organs. Thus, NK cells' activation by dendritic cells allows the killing of transformed or infected cells in the periphery but may also be important for the generation of adaptive immunity. Indeed, it has been shown that NK cells may play a key role in polarizing a Th1 response upon interaction with DCs exposed to microbial products. This regulatory role of DC/NK cross-talk is of particular importance at mucosal surfaces such as the intestine, where the immune system exists in intimate association with commensal bacteria such as lactic acid bacteria (LAB. We here review NK/DC interactions in the presence of gut-derived commensal bacteria and their role in bacterial strain-dependent immunomodulatory effects. We particularly aim to highlight the ability of distinct species of commensal bacterial probiotics to differently affect the outcome of DC/NK cross-talk and consequently to differently influence the polarization of the adaptive immune response.

  4. Dendritic cell immunotherapy for HIV infection: from theory to reality.

    Science.gov (United States)

    Oshiro, Telma Miyuki; de Almeida, Alexandre; da Silva Duarte, Alberto José

    2009-11-01

    Knowledge concerning the immunology of dendritic cells (DCs) accumulated over the last few decades and the development of methodologies to generate and manipulate these cells in vitro has made their therapeutic application a reality. Currently, clinical protocols for DC-based therapeutic vaccine in HIV-infected individuals show that it is a safe and promising approach. Concomitantly, important advances continue to be made in the development of methodologies to optimize DC acquisition, as well as the selection of safe, immunogenic HIV antigens and the evaluation of immune response in treated individuals.

  5. Novel dendritic cell-based vaccination in late stage melanoma.

    Science.gov (United States)

    Schneble, Erika J; Yu, Xianzhong; Wagner, T E; Peoples, George E

    2014-01-01

    Dendritic cells (DCs) are professional antigen-presenting cells (APCs) that play an important role in stimulating an immune response of both CD4(+) T helper cells and CD8(+) cytotoxic T lymphocytes (CTLs). As such, DCs have been studied extensively in cancer immunotherapy for their capability to induce a specific anti-tumor response when loaded with tumor antigens. However, when the most relevant antigens of a tumor remain to be identified, alternative approaches are required. Formation of a dentritoma, a fused DC and tumor cells hybrid, is one strategy. Although initial studies of these hybrid cells are promising, several limitations interfere with its clinical and commercial application. Here we present early experience in clinical trials and an alternative approach to manufacturing this DC/tumor cell hybrid for use in the treatment of late stage and metastatic melanoma.

  6. Dendritic Cell-Based Immunotherapy of Breast Cancer: Modulation by CpG

    National Research Council Canada - National Science Library

    Baar, Joseph

    2004-01-01

    ... in the United States in 2004. Thus, patients with MBC who fail conventional therapies are candidates for clinical trials using novel therapeutic approaches, including immunotherapy. Dendritic cells (DC...

  7. Functional changes of dendritic cells in hypersensivity reactions to amoxicillin

    Directory of Open Access Journals (Sweden)

    C.M.F. Lima

    2010-10-01

    Full Text Available A better understanding of dendritic cell (DC involvement in responses to haptenic drugs is needed, because it represents a possible approach to the development of an in vitro test, which could identify patients prone to drug allergies. There are two main DC subsets: plasmacytoid DC (pDC and myeloid DC (mDC. β-lactams form hapten-carrier conjugates and may provide a suitable model to study DC behavior in drug allergy reactions. It has been demonstrated that drugs interact differently with DC in drug allergic and non-allergic patients, but there are no studies regarding these subsets. Our aim was to assess the functional changes of mDC and pDC harvested from an amoxicillin-hypersensitive 32-year-old woman who experienced a severe maculopapular exanthema as reflected in interleukin-6 (IL-6 production after stimulation with this drug and penicillin. We also aim to demonstrate, for the first time, the feasibility of this method for dendritic cell isolation followed by in vitro stimulation for studies of drug allergy physiopathology. DC were harvested using a double Percoll density gradient, which generates a basophil-depleted cell (BDC suspension. Further, pDC were isolated by blood DC antigen 4-positive magnetic selection and gravity filtration through magnetized columns. After stimulation with amoxicillin, penicillin and positive and negative controls, IL-6 production was measured by ELISA. A positive dose-response curve for IL-6 after stimulation with amoxicillin and penicillin was observed for pDC, but not for mDC or BDC suspension. These preliminary results demonstrate the feasibility of this methodology to expand the knowledge of the effect of dendritic cell activation by drug allergens.

  8. Allergen recognition by innate immune cells: critical role of dendritic and epithelial cells

    Directory of Open Access Journals (Sweden)

    Fabian eSalazar

    2013-11-01

    Full Text Available Allergy is an exacerbated response of the immune system against non-self-proteins called allergens and is typically characterized by biased type-2 T helper cell and deleterious IgE mediated immune responses. The allergic cascade starts with the recognition of allergens by antigen presenting cells, mainly dendritic cells, culminating in mast cell sensitization and triggering. Dendritic cells have been demonstrated to play a crucial role in orchestrating allergic diseases. Using different C-type lectin receptors dendritic cells are able to recognize and internalize a number of allergens from diverse sources leading to sensitization. Furthermore, there is increasing evidence highlighting the role of epithelial cells in triggering and modulating immune responses to allergens. As well as providing a physical barrier, epithelial cells can interact with allergens and influence dendritic cells behaviour through the release of a number of Th2 promoting cytokines. In this review we will summarise current understanding of how allergens are recognised by dendritic cells and epithelial cells and what are the consequences of such interaction in the context of allergic sensitisation and downstream events leading to allergic inflammation. Better understanding of the molecular mechanisms of allergen recognition and associated signalling pathways could enable developing more effective therapeutic strategies that target the initial steps of allergic sensitisation hence hindering development or progression of allergic diseases.

  9. Investigating evolutionary conservation of dendritic cell subset identity and functions

    Directory of Open Access Journals (Sweden)

    Thien-Phong eVu Manh

    2015-06-01

    Full Text Available Dendritic cells (DC were initially defined as mononuclear phagocytes with a dendritic morphology and an exquisite efficiency for naïve T cell activation. DC encompass several subsets initially identified by their expression of specific cell surface molecules and later shown to excel in distinct functions and to develop under the instruction of different transcription factors or cytokines. Very few cell surface molecules are expressed in a specific manner on any immune cell type. Hence, to identify cell types, the sole use of a small number of cell surface markers in classical flow cytometry can be deceiving. Moreover, the markers currently used to define mononuclear phagocyte subsets vary depending on the tissue and animal species studied and even between laboratories. This has led to confusion in the definition of DC subset identity and in their attribution of specific functions. There is a strong need to identify a rigorous and consensus way to define mononuclear phagocyte subsets, with precise guidelines potentially applicable throughout tissues and species. We will discuss the advantages, drawbacks and complementarities of different methodologies: cell surface phenotyping, ontogeny, functional characterization and molecular profiling. We will advocate that gene expression profiling is a very rigorous, largely unbiased and accessible method to define the identity of mononuclear phagocyte subsets, which strengthens and refines surface phenotyping. It is uniquely powerful to yield new, experimentally testable, hypotheses on the ontogeny or functions of mononuclear phagocyte subsets, their molecular regulation and their evolutionary conservation. We propose defining cell populations based on a combination of cell surface phenotyping, expression analysis of hallmark genes and robust functional assays, in order to reach a consensus and integrate faster the huge but scattered knowledge accumulated by different laboratories on different cell types

  10. Leukemia-associated activating mutation of Flt3 expands dendritic cells and alters T cell responses.

    Science.gov (United States)

    Lau, Colleen M; Nish, Simone A; Yogev, Nir; Waisman, Ari; Reiner, Steven L; Reizis, Boris

    2016-03-07

    A common genetic alteration in acute myeloid leukemia is the internal tandem duplication (ITD) in FLT3, the receptor for cytokine FLT3 ligand (FLT3L). Constitutively active FLT3-ITD promotes the expansion of transformed progenitors, but also has pleiotropic effects on hematopoiesis. We analyzed the effect of FLT3-ITD on dendritic cells (DCs), which express FLT3 and can be expanded by FLT3L administration. Pre-leukemic mice with the Flt3(ITD) knock-in allele manifested an expansion of classical DCs (cDCs) and plasmacytoid DCs. The expansion originated in DC progenitors, was cell intrinsic, and was further enhanced in Flt3(ITD/ITD) mice. The mutation caused the down-regulation of Flt3 on the surface of DCs and reduced their responsiveness to Flt3L. Both canonical Batf3-dependent CD8(+) cDCs and noncanonical CD8(+) cDCs were expanded and showed specific alterations in their expression profiles. Flt3(ITD) mice showed enhanced capacity to support T cell proliferation, including a cell-extrinsic expansion of regulatory T (T reg) cells. Accordingly, these mice restricted alloreactive T cell responses during graft-versus-host reaction, but failed to control autoimmunity without T reg cells. Thus, the FLT3-ITD mutation directly affects DC development, indirectly modulating T cell homeostasis and supporting T reg cell expansion. We hypothesize that this effect of FLT3-ITD might subvert immunosurveillance and promote leukemogenesis in a cell-extrinsic manner. © 2016 Lau et al.

  11. Clinical Benefit of Allogeneic Melanoma Cell Lysate-Pulsed Autologous Dendritic Cell Vaccine in MAGE-Positive Colorectal Cancer Patients

    DEFF Research Database (Denmark)

    Toh, Han Chong; Wang, Who-Whong; Chia, Whay Kuang

    2009-01-01

    PURPOSE: We evaluated the clinical benefit of an allogeneic melanoma cell lysate (MCL)-pulsed autologous dendritic cell (DC) vaccine in advanced colorectal cancer patients expressing at least one of six MAGE-A antigens overexpressed by the cell line source of the lysate. EXPERIMENTAL DESIGN: DCs...... were cultured from peripheral blood mononuclear cells (PBMC), pulsed with the allogeneic MCL, and matured using cytokines that achieved high CD83- and CCR7-expressing DCs. Each patient received up to 10 intradermal vaccinations (3-5 x 10(6) cells per dose) at biweekly intervals. RESULTS: Twenty......-free for >27 and >37 months, respectively. This result is particularly meaningful as all patients had progressive disease before treatment. Overall, DC vaccination was associated with a serial decline in regulatory T cells. Using an antibody array, we characterized plasma protein profiles in responding...

  12. Resistivity and thickness effects in dendritic web silicon solar cells

    Science.gov (United States)

    Meier, D. L.; Hwang, J. M.; Greggi, J.; Campbell, R. B.

    1987-01-01

    The decrease of minority carrier lifetime as resistivity decreases in dendritic-web silicon solar cells is addressed. This variation is shown to be consistent with the presence of defect levels in the bandgap which arise from extended defects in the web material. The extended defects are oxide precipitates (SiOx) and the dislocation cores they decorate. Sensitivity to this background distribution of defect levels increases with doping because the Fermi level moves closer to the majority carrier band edge. For high-resistivity dendritic-web silicon, which has a low concentration of these extended defects, cell efficiencies as high as 16.6 percent (4 sq cm, 40 ohm-cm boron-doped base, AM1.5 global, 100 mW/sq cm, 25 C JPL LAPSS1 measurement) and a corresponding electron lifetime of 38 microsec have been obtained. Thickness effects occur in bifacial cell designs and in designs which use light trapping. In some cases, the dislocation/precipitate defect can be passivated through the full thickness of web cells by hydrogen ion implantation.

  13. Xenopus laevis Retinal Ganglion Cell Dendritic Arbors Develop Independently of Visual Stimulation

    Directory of Open Access Journals (Sweden)

    Barbara Lom

    2004-01-01

    Full Text Available Newly formed neurons must locate their appropriate target cells and then form synaptic connections with these targets in order to establish a functional nervous system. In the vertebrate retina, retinal ganglion cell (RGC dendrites extend from the cell body and form synapses with nearby amacrine and bipolar cells. RGC axons, however, exit the retina and synapse with the dendrites of midbrain neurons in the optic tectum. We examined how visual stimulation influenced Xenopus RGC dendritic arborization. Neuronal activity is known to be an important factor in shaping dendritic and axonal arborization. Thus, we reared tadpoles in dark and light environments then used rhodamine dextran retrograde labeling to identify RGCs in the retina. When we compared RGC dendritic arbors from tadpoles reared in dark and light environments, we found no morphological differences, suggesting that physiological visual activity did not contribute to the morphological development of Xenopus RGC dendritic arbors.

  14. Large-Scale mRNA Transfection of Dendritic Cells by Electroporation in Continuous Flow Systems

    DEFF Research Database (Denmark)

    Selmeczi, Dávid; Hansen, Thomas Steen; Met, Özcan

    2016-01-01

    with high cell survival. Continuous flow of suspended dendritic cells through a channel incorporating spatially separated microporous meshes with a synchronized electrical pulsing sequence can yield dendritic cell transfection rates of >75 % with survival rates of >90 %. This chapter describes...

  15. Activation of pulmonary and lymph node dendritic cells during chronic Pseudomonas aeruginosa lung infection in mice

    DEFF Research Database (Denmark)

    Damlund, Dina S. M.; Christophersen, Lars; Jensen, Peter Østrup

    2016-01-01

    , the infection is not eradicated and the inflammatory response leads to gradual degradation of the lung tissue. In CF patients, a Th2-dominated adaptive immune response with a pronounced antibody response is correlated with poorer outcome. Dendritic cells (DCs) are crucial in bridging the innate immune system...... with the adaptive immune response. Once activated, the DCs deliver a set of signals to uncommitted T cells that induce development, such as expansion of regulatory T cells and polarization of Th1, Th2 or Th17 subsets. In this study, we characterized DCs in lungs and regional lymph nodes in BALB/c mice infected...... using intratracheal installation of P. aeruginosa embedded in seaweed alginate in the lungs. A significantly elevated concentration of DCs was detected earlier in the lungs than in the regional lymph nodes. To evaluate whether the chronic P. aeruginosa lung infection leads to activation of DCs...

  16. Cord blood mesenchymal stem cells propel human dendritic cells to an intermediate maturation state and boost interleukin-12 production by mature dendritic cells.

    NARCIS (Netherlands)

    Berk, L.C.J. van den; Roelofs, H.; Huijs, T.; Siebers-Vermeulen, K.G.C.; Raymakers, R.A.P.; Kogler, G.; Figdor, C.G.; Torensma, R.

    2009-01-01

    Pathogen-derived entities force the tissue-resident dendritic cells (DCs) towards a mature state, followed by migration to the draining lymph node to present antigens to T cells. Bone marrow mesenchymal stem cells (MSCs) modulate the differentiation, maturation and function of DCs. In umbilical cord

  17. Bone marrow dendritic cell-based anticancer vaccines

    Czech Academy of Sciences Publication Activity Database

    Indrová, Marie; Mendoza, Luis; Reiniš, Milan; Vonka, V.; Šmahel, M.; Němečková, Š.; Jandlová, Táňa; Bubeník, Jan

    2001-01-01

    Roč. 495, - (2001), s. 355-358 ISSN 0065-2598 R&D Projects: GA MZd NC5526; GA ČR GA312/98/0826; GA ČR GA312/99/0542; GA ČR GA301/00/0114; GA ČR GA301/01/0985; GA AV ČR IAA7052002 Institutional research plan: CEZ:AV0Z5052915 Keywords : HPV16 * dendritic cell s * tumour vaccines Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.513, year: 2000

  18. Functional Identification of Dendritic Cells in the Teleost Model, Rainbow Trout (Oncorhynchus mykiss)

    Science.gov (United States)

    Bassity, Elizabeth; Clark, Theodore G.

    2012-01-01

    Dendritic cells are specialized antigen presenting cells that bridge innate and adaptive immunity in mammals. This link between the ancient innate immune system and the more evolutionarily recent adaptive immune system is of particular interest in fish, the oldest vertebrates to have both innate and adaptive immunity. It is unknown whether dendritic cells co-evolved with the adaptive response, or if the connection between innate and adaptive immunity relied on a fundamentally different cell type early in evolution. We approached this question using the teleost model organism, rainbow trout (Oncorhynchus mykiss), with the aim of identifying dendritic cells based on their ability to stimulate naïve T cells. Adapting mammalian protocols for the generation of dendritic cells, we established a method of culturing highly motile, non-adherent cells from trout hematopoietic tissue that had irregular membrane processes and expressed surface MHCII. When side-by-side mixed leukocyte reactions were performed, these cells stimulated greater proliferation than B cells or macrophages, demonstrating their specialized ability to present antigen and therefore their functional homology to mammalian dendritic cells. Trout dendritic cells were then further analyzed to determine if they exhibited other features of mammalian dendritic cells. Trout dendritic cells were found to have many of the hallmarks of mammalian DCs including tree-like morphology, the expression of dendritic cell markers, the ability to phagocytose small particles, activation by toll-like receptor-ligands, and the ability to migrate in vivo. As in mammals, trout dendritic cells could be isolated directly from the spleen, or larger numbers could be derived from hematopoietic tissue and peripheral blood mononuclear cells in vitro. PMID:22427987

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

    Science.gov (United States)

    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.

  20. Role for Dendritic Cells in Immunoregulation during Experimental Vaginal Candidiasis

    Science.gov (United States)

    LeBlanc, Dana M.; Barousse, Melissa M.; Fidel, Paul L.

    2006-01-01

    Vulvovaginal candidiasis (VVC) caused by the commensal organism Candida albicans remains a significant problem among women of childbearing age, with protection against and susceptibility to infection still poorly understood. While cell-mediated immunity by CD4+ Th1-type cells is protective against most forms of mucosal candidiasis, no protective role for adaptive immunity has been identified against VVC. This is postulated to be due to immunoregulation that prohibits a more profound Candida-specific CD4+ T-cell response against infection. The purpose of this study was to examine the role of dendritic cells (DCs) in the induction phase of the immune response as a means to understand the initiation of the immunoregulatory events. Immunostaining of DCs in sectioned murine lymph nodes draining the vagina revealed a profound cellular reorganization with DCs becoming concentrated in the T-cell zone throughout the course of experimental vaginal Candida infection consistent with cell-mediated immune responsiveness. However, analysis of draining lymph node DC subsets revealed a predominance of immunoregulation-associated CD11c+ B220+ plasmacytoid DCs (pDCs) under both uninfected and infected conditions. Staining of vaginal DCs showed the presence of both DEC-205+ and pDCs, with extension of dendrites into the vaginal lumen of infected mice in close contact with Candida. Flow cytometric analysis of draining lymph node DC costimulatory molecules and activation markers from infected mice indicated a lack of upregulation of major histocompatibility complex class II, CD80, CD86, and CD40 during infection, consistent with a tolerizing condition. Together, the results suggest that DCs are involved in the immunoregulatory events manifested during a vaginal Candida infection and potentially through the action of pDCs. PMID:16714548

  1. Inorganic arsenic impairs differentiation and functions of human dendritic cells

    Energy Technology Data Exchange (ETDEWEB)

    Macoch, Mélinda; Morzadec, Claudie [UMR INSERM U1085, Institut de Recherche sur la Santé, l' Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France); Fardel, Olivier [UMR INSERM U1085, Institut de Recherche sur la Santé, l' Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France); Pôle Biologie, Centre Hospitalier Universitaire (CHU) Rennes, 2 rue Henri Le Guilloux, 35033 Rennes (France); Vernhet, Laurent, E-mail: laurent.vernhet@univ-rennes1.fr [UMR INSERM U1085, Institut de Recherche sur la Santé, l' Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France)

    2013-01-15

    Experimental studies have demonstrated that the antileukemic trivalent inorganic arsenic prevents the development of severe pro-inflammatory diseases mediated by excessive Th1 and Th17 cell responses. Differentiation of Th1 and Th17 subsets is mainly regulated by interleukins (ILs) secreted from dendritic cells (DCs) and the ability of inorganic arsenic to impair interferon-γ and IL-17 secretion by interfering with the physiology of DCs is unknown. In the present study, we demonstrate that high concentrations of sodium arsenite (As(III), 1–2 μM) clinically achievable in plasma of arsenic-treated patients, block differentiation of human peripheral blood monocytes into immature DCs (iDCs) by inducing their necrosis. Differentiation of monocytes in the presence of non-cytotoxic concentrations of As(III) (0.1 to 0.5 μM) only slightly impacts endocytotic activity of iDCs or expression of co-stimulatory molecules in cells activated with lipopolysaccharide. However, this differentiation in the presence of As(III) strongly represses secretion of IL-12p70 and IL-23, two major regulators of Th1 and Th17 activities, from iDCs stimulated with different toll-like receptor (TLR) agonists in metalloid-free medium. Such As(III)-exposed DCs also exhibit reduced mRNA levels of IL12A and/or IL12B genes when activated with TLR agonists. Finally, differentiation of monocytes with non-cytotoxic concentrations of As(III) subsequently reduces the ability of activated DCs to stimulate the release of interferon-γ and IL-17 from Th cells. In conclusion, our results demonstrate that clinically relevant concentrations of inorganic arsenic markedly impair in vitro differentiation and functions of DCs, which may contribute to the putative beneficial effects of the metalloid towards inflammatory autoimmune diseases. Highlights: ► Inorganic arsenic impairs differentiation and functions of human dendritic cells (DCs) ► Arsenite (> 1 μM) blocks differentiation of dendritic cells by

  2. Inorganic arsenic impairs differentiation and functions of human dendritic cells

    International Nuclear Information System (INIS)

    Macoch, Mélinda; Morzadec, Claudie; Fardel, Olivier; Vernhet, Laurent

    2013-01-01

    Experimental studies have demonstrated that the antileukemic trivalent inorganic arsenic prevents the development of severe pro-inflammatory diseases mediated by excessive Th1 and Th17 cell responses. Differentiation of Th1 and Th17 subsets is mainly regulated by interleukins (ILs) secreted from dendritic cells (DCs) and the ability of inorganic arsenic to impair interferon-γ and IL-17 secretion by interfering with the physiology of DCs is unknown. In the present study, we demonstrate that high concentrations of sodium arsenite (As(III), 1–2 μM) clinically achievable in plasma of arsenic-treated patients, block differentiation of human peripheral blood monocytes into immature DCs (iDCs) by inducing their necrosis. Differentiation of monocytes in the presence of non-cytotoxic concentrations of As(III) (0.1 to 0.5 μM) only slightly impacts endocytotic activity of iDCs or expression of co-stimulatory molecules in cells activated with lipopolysaccharide. However, this differentiation in the presence of As(III) strongly represses secretion of IL-12p70 and IL-23, two major regulators of Th1 and Th17 activities, from iDCs stimulated with different toll-like receptor (TLR) agonists in metalloid-free medium. Such As(III)-exposed DCs also exhibit reduced mRNA levels of IL12A and/or IL12B genes when activated with TLR agonists. Finally, differentiation of monocytes with non-cytotoxic concentrations of As(III) subsequently reduces the ability of activated DCs to stimulate the release of interferon-γ and IL-17 from Th cells. In conclusion, our results demonstrate that clinically relevant concentrations of inorganic arsenic markedly impair in vitro differentiation and functions of DCs, which may contribute to the putative beneficial effects of the metalloid towards inflammatory autoimmune diseases. Highlights: ► Inorganic arsenic impairs differentiation and functions of human dendritic cells (DCs) ► Arsenite (> 1 μM) blocks differentiation of dendritic cells by

  3. Targeting Antigens to Dec-205 on Dendritic Cells Induces Immune Protection in Experimental Colitis in Mice

    Science.gov (United States)

    Wadwa, Munisch; Klopfleisch, Robert; Buer, Jan; Westendorf, Astrid M.

    2016-01-01

    The endocytotic c-type lectin receptor DEC-205 is highly expressed on immature dendritic cells. In previous studies, it was shown that antigen-targeting to DEC-205 is a useful tool for the induction of antigen-specific Foxp3+ regulatory T cells and thereby can prevent inflammatory processes. However, whether this approach is sufficient to mediate tolerance in mucosal tissues like the gut is unknown. In this study, we established a new mouse model in which the adoptive transfer of naive hemagglutinin (HA)-specific CD4+Foxp3– T cells into VILLIN-HA transgenic mice leads to severe colitis. To analyze if antigen-targeting to DEC-205 could protect against inflammation of the gut, VILLIN-HA transgenic mice were injected with an antibody–antigen complex consisting of the immunogenic HA110–120 peptide coupled to an α-DEC-205 antibody (DEC-HA) before adoptive T cell transfer. DEC-HA-treated mice showed significantly less signs of intestinal inflammation as was demonstrated by reduced loss of body weight and histopathology in the gut. Strikingly, abrogated intestinal inflammation was mediated via the conversion of naive HA-specific CD4+Foxp3– T cells into HA-specific CD4+Foxp3+ regulatory T cells. In this study, we provide evidence that antigen-targeting to DEC-205 can be utilized for the induction of tolerance in mucosal organs that are confronted with large numbers of exogenous antigens. PMID:27141310

  4. CD1 and major histocompatibility complex II molecules follow a different course during dendritic cell maturation

    NARCIS (Netherlands)

    van der Wel, Nicole N.; Sugita, Masahiko; Fluitsma, Donna M.; Cao, Xaiochun; Schreibelt, Gerty; Brenner, Michael B.; Peters, Peter J.

    2003-01-01

    The maturation of dendritic cells is accompanied by the redistribution of major histocompatibility complex (MHC) class II molecules from the lysosomal MHC class IT compartment to the plasma membrane to mediate presentation of peptide antigens. Besides MHC molecules, dendritic cells also express CD1

  5. IRF8 Transcription-Factor-Dependent Classical Dendritic Cells Are Essential for Intestinal T Cell Homeostasis

    DEFF Research Database (Denmark)

    Luda, Katarzyna M.; Joeris, Thorsten; Persson, Emma K.

    2016-01-01

    The role of dendritic cells (DCs) in intestinal immune homeostasis remains incompletely defined. Here we show that mice lacking IRF8 transcription-factor-dependent DCs had reduced numbers of T cells in the small intestine (SI), but not large intestine (LI), including an almost complete absence...... dependent DCs in the maintenance of intestinal T cell homeostasis....

  6. Leishmania major Infection Activates NF-κB and Interferon Regulatory Factors 1 and 8 in Human Dendritic Cells▿

    Science.gov (United States)

    Jayakumar, Asha; Donovan, Michael J.; Tripathi, Vinita; Ramalho-Ortigao, Marcelo; McDowell, Mary Ann

    2008-01-01

    The salient feature of dendritic cells (DC) is the initiation of appropriate adaptive immune responses by discriminating between pathogens. Using a prototypic model of intracellular infection, we previously showed that Leishmania major parasites prime human DC for efficient interleukin-12 (IL-12) secretion. L. major infection is associated with self-limiting cutaneous disease and powerful immunity. In stark contrast, the causative agent of visceral leishmaniasis, Leishmania donovani, does not prime human DC for IL-12 production. Here, we report that DC priming by L. major infection results in the early activation of NF-κB transcription factors and the up-regulation and nuclear translocation of interferon regulatory factor 1 (IRF-1) and IRF-8. The inhibition of NF-κB activation by the pretreatment of DC with caffeic acid phenethyl ester blocks L. major-induced IRF-1 and IRF-8 activation and IL-12 expression. We further demonstrate that IRF-1 and IRF-8 obtained from L. major-infected human DC specifically bind to their consensus binding sites on the IL-12p35 promoter, indicating that L. major infection either directly stimulates a signaling cascade or induces an autocrine pathway that activates IRF-1 and IRF-8, ultimately resulting in IL-12 transcription. PMID:18316378

  7. Regulatory T cell effects in antitumor laser immunotherapy: a mathematical model and analysis

    Science.gov (United States)

    Dawkins, Bryan A.; Laverty, Sean M.

    2016-03-01

    Regulatory T cells (Tregs) have tremendous influence on treatment outcomes in patients receiving immunotherapy for cancerous tumors. We present a mathematical model incorporating the primary cellular and molecular components of antitumor laser immunotherapy. We explicitly model developmental classes of dendritic cells (DCs), cytotoxic T cells (CTLs), primary and metastatic tumor cells, and tumor antigen. Regulatory T cells have been shown to kill antigen presenting cells, to influence dendritic cell maturation and migration, to kill activated killer CTLs in the tumor microenvironment, and to influence CTL proliferation. Since Tregs affect explicitly modeled cells, but we do not explicitly model dynamics of Treg themselves, we use model parameters to analyze effects of Treg immunosuppressive activity. We will outline a systematic method for assigning clinical outcomes to model simulations and use this condition to associate simulated patient treatment outcome with Treg activity.

  8. GM-CSF Controls Nonlymphoid Tissue Dendritic Cell Homeostasis but Is Dispensable for the Differentiation of Inflammatory Dendritic Cells

    Science.gov (United States)

    Greter, Melanie; Helft, Julie; Chow, Andrew; Hashimoto, Daigo; Mortha, Arthur; Agudo-Cantero, Judith; Bogunovic, Milena; Gautier, Emmanuel L.; Miller, Jennifer; Leboeuf, Marylene; Lu, Geming; Aloman, Costica; Brown, Brian D.; Pollard, Jeffrey W.; Xiong, Huabao; Randolph, Gwendalyn J.; Chipuk, Jerry E.; Frenette, Paul S.; Merad, Miriam

    2012-01-01

    SUMMARY GM-CSF (Csf-2) is a critical cytokine for the in vitro generation of dendritic cells (DCs) and is thought to control the development of inflammatory DCs and resident CD103+ DCs in some tissues. Here we showed that in contrast to the current understanding, Csf-2 receptor acts in the steady state to promote the survival and homeostasis of nonlymphoid tissue-resident CD103+ and CD11b+ DCs. Absence of Csf-2 receptor on lung DCs abrogated the induction of CD8+ T cell immunity after immunization with particulate antigens. In contrast, Csf-2 receptor was dispensable for the differentiation and innate function of inflammatory DCs during acute injuries. Instead, inflammatory DCs required Csf-1 receptor for their development. Thus, Csf-2 is important in vaccine-induced CD8+ T cell immunity through the regulation of nonlymphoid tissue DC homeostasis rather than control of inflammatory DCs in vivo. PMID:22749353

  9. Curcumin prevents human dendritic cell response to immune stimulants

    International Nuclear Information System (INIS)

    Shirley, Shawna A.; Montpetit, Alison J.; Lockey, R.F.; Mohapatra, Shyam S.

    2008-01-01

    Curcumin, a compound found in the Indian spice turmeric, has anti-inflammatory and immunomodulatory properties, though the mechanism remains unclear. Dendritic cells (DCs) are important to generating an immune response and the effect of curcumin on human DCs has not been explored. The role curcumin in the DC response to bacterial and viral infection was investigated in vitro using LPS and Poly I:C as models of infection. CD14 + monocytes, isolated from human peripheral blood, were cultured in GM-CSF- and IL-4-supplemented medium to generate immature DCs. Cultures were incubated with curcumin, stimulated with LPS or Poly I:C and functional assays were performed. Curcumin prevents DCs from responding to immunostimulants and inducing CD4 + T cell proliferation by blocking maturation marker, cytokine and chemokine expression and reducing both migration and endocytosis. These data suggest a therapeutic role for curcumin as an immune suppressant

  10. Immunological Characterization of Whole Tumour Lysate-Loaded Dendritic Cells for Cancer Immunotherapy

    Science.gov (United States)

    Ottobrini, Luisa; Biasin, Mara; Borelli, Manuela; Lucignani, Giovanni; Trabattoni, Daria; Clerici, Mario

    2016-01-01

    Introduction 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. Matherials & Methods 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 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. Conclusion Data herein could be useful in the design of antitumoral DC-based therapies, showing a specific activation of immune system against breast cancer. PMID:26795765

  11. Dendritic branching of olfactory bulb mitral and tufted cells: regulation by TrkB.

    Directory of Open Access Journals (Sweden)

    Fumiaki Imamura

    2009-08-01

    Full Text Available Projection neurons of mammalian olfactory bulb (OB, mitral and tufted cells, have dendrites whose morphologies are specifically differentiated for efficient odor information processing. The apical dendrite extends radially and arborizes in single glomerulus where it receives primary input from olfactory sensory neurons that express the same odor receptor. The lateral dendrites extend horizontally in the external plexiform layer and make reciprocal dendrodendritic synapses with granule cells, which moderate mitral/tufted cell activity. The molecular mechanisms regulating dendritic development of mitral/tufted cells is one of the unsolved important problems in the olfactory system. Here, we focused on TrkB receptors to test the hypothesis that neurotrophin-mediate mechanisms contributed to dendritic differentiation of OB mitral/tufted cells.With immunohistochemical analysis, we found that the TrkB neurotrophin receptor is expressed by both apical and lateral dendrites of mitral/tufted cells and that expression is evident during the early postnatal days when these dendrites exhibit their most robust growth and differentiation. To examine the effect of TrkB activation on mitral/tufted cell dendritic development, we cultured OB neurons. When BDNF or NT4 were introduced into the cultures, there was a significant increase in the number of primary neurites and branching points among the mitral/tufted cells. Moreover, BDNF facilitated filopodial extension along the neurites of mitral/tufted cells.In this report, we show for the first time that TrkB activation stimulates the dendritic branching of mitral/tufted cells in developing OB. This suggests that arborization of the apical dendrite in a glomerulus is under the tight regulation of TrkB activation.

  12. 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.

  13. Mannosylated biodegradable polyethyleneimine for targeted DNA delivery to dendritic cells

    Directory of Open Access Journals (Sweden)

    Sun X

    2012-06-01

    Full Text Available Xun Sun, Simu Chen, Jianfeng Han, Zhirong ZhangKey Laboratory of Drug Targeting and Drug Delivery System, Ministry of Education, West China School of Pharmacy, Sichuan University, Chengdu, People’s Republic of ChinaBackground: To establish a potential gene-delivery system with the ability to deliver plasmid DNA to dendritic cells (DCs more efficiently and specifically, we designed and synthesized a low-molecular-weight polyethyleneimine and triethyleneglycol polymer (PEI–TEG and a series of its mannosylated derivatives.Methods: PEI–TEG was synthesized from PEI2000 and PEI600 with TEG as the cross-linker. PEI–TEG was then linked to mannose via a phenylisothiocyanate bridge to obtain man-PEI–TEG conjugates. The DNA conveyance abilities of PEI–TEG, man-PEI–TEG, as well as control PEI25k were evaluated by measuring their zeta potential, particle size, and DNA-binding abilities. The in vitro cytotoxicity, cell uptake, and transfection efficiency of these PEI/DNA complexes were examined on the DC2.4 cell line. Finally, a maturation experiment evaluated the effect of costimulatory molecules CD40, CD80, and CD86 on murine bone marrow-derived DCs (BMDCs using flow cytometry.Results: PEI–TEG and man-PEI–TEG were successfully synthesized and were shown to retain the excellent properties of PEI25k for condensing DNA. Compared with PEI–TEG as well as PEI25k, the man-PEI–TEG had less cytotoxicity and performed better in both cellular uptake and transfection assays in vitro. The results of the maturation experiment showed that all the PEI/DNA complexes induced an adequate upregulation of surface markers for DC maturation.Conclusion: These results demonstrated that man-PEI–TEG can be employed as a DC-targeting gene-delivery system.Keywords: dendritic cells, DCs, mannose, polyethyleneimine, PEI, gene delivery

  14. Dendritic cells for active anti-cancer immunotherapy: targeting activation pathways through genetic modification.

    Science.gov (United States)

    Breckpot, Karine; Escors, David

    2009-12-01

    Tumour immunotherapy has become a treatment modality for cancer, harnessing the immune system to recognize and eradicate tumour cells specifically. It is based on the expression of tumour associated antigens (TAA) by the tumour cells and aims at the induction of TAA-specific effector T cell responses, whilst overruling various mechanisms that can hamper the anti-tumour immune response, e.g. regulatory T cells (Treg). (Re-) activation of effector T cells requires the completion of a carefully orchestrated series of specific steps. Particularly important is the provision of TAA presentation and strong stimulatory signals, delivered by co-stimulatory surface molecules and cytokines. These can only be delivered by professional antigen-presenting cells, in particular dendritic cells (DC). Therefore, DC need to be loaded with TAA and appropriately activated. It is not surprising that an extensive part of DC research has focused on the delivery of both TAA and activation signals to DC, developing a one step approach to obtain potent stimulatory DC. The simultaneous delivery of TAA and activation signals is therefore the topic of this review, emphasizing the role of DC in mediating T cell activation and how we can manipulate DC for the pill-pose of enhancing tumour immunotherapy. As we gain a better understanding of the molecular and cellular mechanisms that mediate induction of TAA-specific T cells, rational approaches for the activation of T cell responses can be developed for the treatment of cancer.

  15. CD83 Antibody Inhibits Human B Cell Responses to Antigen as well as Dendritic Cell-Mediated CD4 T Cell Responses.

    Science.gov (United States)

    Wong, Kuan Y; Baron, Rebecca; Seldon, Therese A; Jones, Martina L; Rice, Alison M; Munster, David J

    2018-05-15

    Anti-CD83 Ab capable of Ab-dependent cellular cytotoxicity can deplete activated CD83 + human dendritic cells, thereby inhibiting CD4 T cell-mediated acute graft-versus-host disease. As CD83 is also expressed on the surface of activated B lymphocytes, we hypothesized that anti-CD83 would also inhibit B cell responses to stimulation. We found that anti-CD83 inhibited total IgM and IgG production in vitro by allostimulated human PBMC. Also, Ag-specific Ab responses to immunization of SCID mice xenografted with human PBMC were inhibited by anti-CD83 treatment. This inhibition occurred without depletion of all human B cells because anti-CD83 lysed activated CD83 + B cells by Ab-dependent cellular cytotoxicity and spared resting (CD83 - ) B cells. In cultured human PBMC, anti-CD83 inhibited tetanus toxoid-stimulated B cell proliferation and concomitant dendritic cell-mediated CD4 T cell proliferation and expression of IFN-γ and IL-17A, with minimal losses of B cells (80% of B cells but had no effect on CD4 T cell proliferation and cytokine expression. By virtue of the ability of anti-CD83 to selectively deplete activated, but not resting, B cells and dendritic cells, with the latter reducing CD4 T cell responses, anti-CD83 may be clinically useful in autoimmunity and transplantation. Advantages might include inhibited expansion of autoantigen- or alloantigen-specific B cells and CD4 T cells, thus preventing further production of pathogenic Abs and inflammatory cytokines while preserving protective memory and regulatory cells. Copyright © 2018 by The American Association of Immunologists, Inc.

  16. Unique proteomic signatures distinguish macrophages and dendritic cells.

    Directory of Open Access Journals (Sweden)

    Lev Becker

    Full Text Available Monocytes differentiate into heterogeneous populations of tissue macrophages and dendritic cells (DCs that regulate inflammation and immunity. Identifying specific populations of myeloid cells in vivo is problematic, however, because only a limited number of proteins have been used to assign cellular phenotype. Using mass spectrometry and bone marrow-derived cells, we provided a global view of the proteomes of M-CSF-derived macrophages, classically and alternatively activated macrophages, and GM-CSF-derived DCs. Remarkably, the expression levels of half the plasma membrane proteins differed significantly in the various populations of cells derived in vitro. Moreover, the membrane proteomes of macrophages and DCs were more distinct than those of classically and alternatively activated macrophages. Hierarchical cluster and dual statistical analyses demonstrated that each cell type exhibited a robust proteomic signature that was unique. To interrogate the phenotype of myeloid cells in vivo, we subjected elicited peritoneal macrophages harvested from wild-type and GM-CSF-deficient mice to mass spectrometric and functional analysis. Unexpectedly, we found that peritoneal macrophages exhibited many features of the DCs generated in vitro. These findings demonstrate that global analysis of the membrane proteome can help define immune cell phenotypes in vivo.

  17. High Fat Diet Inhibits Dendritic Cell and T Cell Response to Allergens but Does Not Impair Inhalational Respiratory Tolerance.

    Directory of Open Access Journals (Sweden)

    Angela Pizzolla

    Full Text Available The incidence of obesity has risen to epidemic proportions in recent decades, most commonly attributed to an increasingly sedentary lifestyle, and a 'western' diet high in fat and low in fibre. Although non-allergic asthma is a well-established co-morbidity of obesity, the influence of obesity on allergic asthma is still under debate. Allergic asthma is thought to result from impaired tolerance to airborne antigens, so-called respiratory tolerance. We sought to investigate whether a diet high in fats affects the development of respiratory tolerance. Mice fed a high fat diet (HFD for 8 weeks showed weight gain, metabolic disease, and alteration in gut microbiota, metabolites and glucose metabolism compared to age-matched mice fed normal chow diet (ND. Respiratory tolerance was induced by repeated intranasal (i.n. administration of ovalbumin (OVA, prior to induction of allergic airway inflammation (AAI by sensitization with OVA in alum i.p. and subsequent i.n. OVA challenge. Surprisingly, respiratory tolerance was induced equally well in HFD and ND mice, as evidenced by decreased lung eosinophilia and serum OVA-specific IgE production. However, in a pilot study, HFD mice showed a tendency for impaired activation of airway dendritic cells and regulatory T cells compared with ND mice after induction of respiratory tolerance. Moreover, the capacity of lymph node cells to produce IL-5 and IL-13 after AAI was drastically diminished in HFD mice compared to ND mice. These results indicate that HFD does not affect the inflammatory or B cell response to an allergen, but inhibits priming of Th2 cells and possibly dendritic cell and regulatory T cell activation.

  18. Multiple modes of action potential initiation and propagation in mitral cell primary dendrite

    DEFF Research Database (Denmark)

    Chen, Wei R; Shen, Gongyu Y; Shepherd, Gordon M

    2002-01-01

    recordings with computational modeling to analyze action-potential initiation and propagation in the primary dendrite. In response to depolarizing current injection or distal olfactory nerve input, fast Na(+) action potentials were recorded along the entire length of the primary dendritic trunk. With weak......-to-moderate olfactory nerve input, an action potential was initiated near the soma and then back-propagated into the primary dendrite. As olfactory nerve input increased, the initiation site suddenly shifted to the distal primary dendrite. Multi-compartmental modeling indicated that this abrupt shift of the spike......-initiation site reflected an independent thresholding mechanism in the distal dendrite. When strong olfactory nerve excitation was paired with strong inhibition to the mitral cell basal secondary dendrites, a small fast prepotential was recorded at the soma, which indicated that an action potential was initiated...

  19. Deficiency of autoimmune regulator impairs the immune tolerance effect of bone marrow-derived dendritic cells in mice.

    Science.gov (United States)

    Huo, Feifei; Li, Dongbei; Zhao, Bo; Luo, Yadong; Zhao, Bingjie; Zou, Xueyang; Li, Yi; Yang, Wei

    2018-02-01

    As a transcription factor, autoimmune regulator (Aire) participates in thymic negative selection and maintains immune tolerance mainly by regulating the ectopic expression of tissue-restricted antigens (TRAs) in medullary thymic epithelial cells (mTECs). Aire is also expressed in dendritic cells (DCs). DCs are professional antigen-presenting cells (APCs) that affect the differentiation of T cells toward distinct subpopulations and participate in the immune response and tolerance, thereby playing an important role in maintaining homeostasis. To determine the role of Aire in maintaining immune tolerance by bone marrow-derived dendritic cells (BMDCs), in the present study we utilized Aire-knockout mice to examine the changes of maturation status and TRAs expression on BMDCs, additionally investigate the differentiation of CD4 + T cells. The results showed that expression of costimulatory molecule and major histocompatibility complex class II (MHC-II) molecule was increased and expression of various TRAs was decreased in BMDCs from Aire-knockout mice. Aire deficiency reduced the differentiation of naïve CD4 + T cells into type 2T helper (Th2) cells and regulatory T cells (Tregs) but enhanced the differentiation of naïve CD4 + T cells into Th1 cells, Th17 cells, and follicular helper T (Tfh) cells. The results demonstrate that Aire expressed by BMDCs plays an important role in the maintenance of homeostasis by regulating TRA expression and the differentiation of T cell subsets.

  20. Regulatory T Cells in Radiotherapeutic Responses

    International Nuclear Information System (INIS)

    Schaue, Dörthe; Xie, Michael W.; Ratikan, Josephine A.; McBride, William H.

    2012-01-01

    Radiation therapy (RT) can extend its influence in cancer therapy beyond what can be attributed to in-field cytotoxicity by modulating the immune system. While complex, these systemic effects can help tip the therapeutic balance in favor of treatment success or failure. Engagement of the immune system is generally through recognition of damage-associated molecules expressed or released as a result of tumor and normal tissue radiation damage. This system has evolved to discriminate pathological from physiological forms of cell death by signaling “danger.” The multiple mechanisms that can be evoked include a shift toward a pro-inflammatory, pro-oxidant microenvironment that can promote maturation of dendritic cells and, in cancer treatment, the development of effector T cell responses to tumor-associated antigens. Control over these processes is exerted by regulatory T cells (Tregs), suppressor macrophages, and immunosuppressive cytokines that act in consort to maintain tolerance to self, limit tissue damage, and re-establish tissue homeostasis. Unfortunately, by the time RT for cancer is initiated the tumor-host relationship has already been sculpted in favor of tumor growth and against immune-mediated mechanisms for tumor regression. Reversing this situation is a major challenge. However, recent data show that removal of Tregs can tip the balance in favor of the generation of radiation-induced anti-tumor immunity. The clinical challenge is to do so without excessive depletion that might precipitate serious autoimmune reactions and increase the likelihood of normal tissue complications. The selective modulation of Treg biology to maintain immune tolerance and control of normal tissue damage, while releasing the “brakes” on anti-tumor immune responses, is a worthy aim with promise for enhancing the therapeutic benefit of RT for cancer.

  1. Regulatory T cells in radiotherapeutic responses

    Directory of Open Access Journals (Sweden)

    Dörthe eSchaue

    2012-08-01

    Full Text Available Radiation therapy (RT can extend its influence in cancer therapy beyond what can be attributed to in-field cytotoxicity by modulating the immune system. While complex, these systemic effects can help tip the therapeutic balance in favor of treatment success or failure. Engagement of the immune system is generally through recognition of damage-associated molecules expressed or released as a result of tumor and normal tissue radiation damage. This system has evolved to discriminate pathological from physiological forms of cell death by signaling danger. The multiple mechanisms that can be evoked include a shift towards a pro-inflammatory, pro-oxidant microenvironment that can promote maturation of dendritic cells and, in cancer treatment, the development of effector T cell responses to tumor-associated antigens. Control over these processes is exerted by regulatory T cells (Tregs, suppressor macrophages and immunosuppressive cytokines that act in consort to maintain tolerance to self, limit tissue damage, and re-establish tissue homeostasis. Unfortunately, by the time RT for cancer is initiated the tumor-host relationship has already been sculpted in favor of tumor growth and against immune-mediated mechanisms for tumor regression. Reversing this situation is a major challenge. However, recent data show that removal of Tregs can tip the balance in favor of the generation of radiation-induced anti-tumor immunity. The clinical challenge is to do so without excessive depletion that might precipitate serious autoimmune reactions and increase the likelihood of normal tissue complications. The selective modulation of Treg biology to maintain immune tolerance and control of normal tissue damage, while releasing the brakes on anti-tumor immune responses, is a worthy aim with promise for enhancing the therapeutic benefit of RT for cancer.

  2. Burn injury suppresses human dermal dendritic cell and Langerhans cell function

    NARCIS (Netherlands)

    van den Berg, Linda M.; de Jong, Marein A. W. P.; Witte, Lot de; Ulrich, Magda M. W.; Geijtenbeek, Teunis B. H.

    2011-01-01

    Human skin contains epidermal Langerhans cells (LCs) and dermal dendritic cells (DCs) that are key players in induction of adaptive immunity upon infection. After major burn injury, suppressed adaptive immunity has been observed in patients. Here we demonstrate that burn injury affects adaptive

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

    Directory of Open Access Journals (Sweden)

    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.

  4. Cysticerci Drive Dendritic Cells to Promote In Vitro and In Vivo Tregs Differentiation

    Directory of Open Access Journals (Sweden)

    Laura Adalid-Peralta

    2013-01-01

    Full Text Available Regulatory T cells (Tregs play a crucial role in immune homeostasis. Treg induction is a strategy that parasites have evolved to modulate the host’s inflammatory environment, facilitating their establishment and permanence. In human Taenia solium neurocysticercosis (NC, the concurrence of increased peripheral and central Treg levels and their capacity to inhibit T cell activation and proliferation support their role in controlling neuroinflammation. This study is aimed at identifing possible mechanisms of Treg induction in human NC. Monocyte-derived dendritic cells (DC from healthy human donors, cocultivated with autologous CD4+ naïve cells either in the presence or absence of cysticerci, promoted CD25highFoxp3+ Treg differentiation. An increased Treg induction was observed when cysticerci were present. Moreover, an augmentation of suppressive-related molecules (SLAMF1, B7-H1, and CD205 was found in parasite-induced DC differentiation. Increased Tregs and a higher in vivo DC expression of the regulatory molecules SLAMF1 and CD205 in NC patients were also found. SLAMF1 gene was downregulated in NC patients with extraparenchymal cysticerci, exhibiting higher inflammation levels than patients with parenchymal parasites. Our findings suggest that cysticerci may modulate DC to favor a suppressive environment, which may help parasite establishment, minimizing the excessive inflammation, which may lead to tissue damage.

  5. Cysticerci drive dendritic cells to promote in vitro and in vivo Tregs differentiation.

    Science.gov (United States)

    Adalid-Peralta, Laura; Arce-Sillas, Asiel; Fragoso, Gladis; Cárdenas, Graciela; Rosetti, Marcos; Casanova-Hernández, Didier; Rangel-Escareño, Claudia; Uribe-Figueroa, Laura; Fleury, Agnes; Sciutto, Edda

    2013-01-01

    Regulatory T cells (Tregs) play a crucial role in immune homeostasis. Treg induction is a strategy that parasites have evolved to modulate the host's inflammatory environment, facilitating their establishment and permanence. In human Taenia solium neurocysticercosis (NC), the concurrence of increased peripheral and central Treg levels and their capacity to inhibit T cell activation and proliferation support their role in controlling neuroinflammation. This study is aimed at identifing possible mechanisms of Treg induction in human NC. Monocyte-derived dendritic cells (DC) from healthy human donors, cocultivated with autologous CD4(+) naïve cells either in the presence or absence of cysticerci, promoted CD25(high)Foxp3+ Treg differentiation. An increased Treg induction was observed when cysticerci were present. Moreover, an augmentation of suppressive-related molecules (SLAMF1, B7-H1, and CD205) was found in parasite-induced DC differentiation. Increased Tregs and a higher in vivo DC expression of the regulatory molecules SLAMF1 and CD205 in NC patients were also found. SLAMF1 gene was downregulated in NC patients with extraparenchymal cysticerci, exhibiting higher inflammation levels than patients with parenchymal parasites. Our findings suggest that cysticerci may modulate DC to favor a suppressive environment, which may help parasite establishment, minimizing the excessive inflammation, which may lead to tissue damage.

  6. Effects of Aedes aegypti salivary components on dendritic cell and lymphocyte biology

    Czech Academy of Sciences Publication Activity Database

    Bizzarro, B.; Barros, M.S.; Maciel, C.; Gueroni, D.I.; Lino, C.N.; Campopiano, J.; Kotsyfakis, Michalis; Amarante-Mendes, G.P.; Calvo, E.; Capurro, M.L.; Sa-Nunes, A.

    2013-01-01

    Roč. 6, NOV 2013 (2013), s. 329 ISSN 1756-3305 Institutional support: RVO:60077344 Keywords : dendritic cells * T-cells * Aedes aegypti * saliva * apoptosis Subject RIV: EC - Immunology Impact factor: 3.251, year: 2013

  7. Targeting Radiation Therapy for Developing Dendritic Cell Based Immunotherapy of Metastatic Prostate Cancer

    National Research Council Canada - National Science Library

    Chakravarty, Prabir K

    2006-01-01

    .... The hypothesis was tested using a murine prostate cancer model, RM-1. The study showed that irradiation induces apoptosis and the irradiated tumor cells were able to activate dendritic cells and stimulate tumor specific immune response in vitro...

  8. Geometry sensing by dendritic cells dictates spatial organization and PGE(2)-induced dissolution of podosomes.

    NARCIS (Netherlands)

    Dries, K. van den; Helden, S.F.G. van; Riet, J.T. te; Diez-Ahedo, R.; Manzo, C.; Oud, M.M.; Leeuwen, F.N. van; Brock, R.E.; Garcia-Parajo, M.F.; Cambi, A.; Figdor, C.G.

    2012-01-01

    Assembly and disassembly of adhesion structures such as focal adhesions (FAs) and podosomes regulate cell adhesion and differentiation. On antigen-presenting dendritic cells (DCs), acquisition of a migratory and immunostimulatory phenotype depends on podosome dissolution by prostaglandin E(2)

  9. Human B cells induce dendritic cell maturation and favour Th2 polarization by inducing OX-40 ligand

    Science.gov (United States)

    Maddur, Mohan S.; Sharma, Meenu; Hegde, Pushpa; Stephen-Victor, Emmanuel; Pulendran, Bali; Kaveri, Srini V.; Bayry, Jagadeesh

    2015-01-01

    Dendritic cells (DCs) play a critical role in immune homeostasis by regulating the functions of various immune cells, including T and B cells. Notably, DCs also undergo education on reciprocal signalling by these immune cells and environmental factors. Various reports demonstrated that B cells have profound regulatory functions, although only few reports have explored the regulation of human DCs by B cells. Here we demonstrate that activated but not resting B cells induce maturation of DCs with distinct features to polarize Th2 cells that secrete interleukin (IL)-5, IL-4 and IL-13. B-cell-induced maturation of DCs is contact dependent and implicates signalling of B-cell activation molecules CD69, B-cell-activating factor receptor, and transmembrane activator and calcium-modulating cyclophilin ligand interactor. Mechanistically, differentiation of Th2 cells by B-cell-matured DCs is dependent on OX-40 ligand. Collectively, our results suggest that B cells have the ability to control their own effector functions by enhancing the ability of human DCs to mediate Th2 differentiation. PMID:24910129

  10. Plant-based oral tolerance to hemophilia therapy employs a complex immune regulatory response including LAP+CD4+ T cells

    OpenAIRE

    Wang, Xiaomei; Su, Jin; Sherman, Alexandra; Rogers, Geoffrey L.; Liao, Gongxian; Hoffman, Brad E.; Leong, Kam W.; Terhorst, Cox; Daniell, Henry; Herzog, Roland W.

    2015-01-01

    Coadministering FIX orally and systemically induces tolerance via complex immune regulation, involving tolerogenic dendritic and T-cell subsets.Induced CD4+CD25−LAP+ regulatory T cells with increased IL-10 and TGF-β expression and CD4+CD25+ regulatory T cells suppress antibody formation against FIX.

  11. The chemokine receptor CCR2 maintains plasmacytoid dendritic cell homeostasis

    DEFF Research Database (Denmark)

    Cédile, Oriane; Østerby Jørgensen, Line; Frank, Ida

    2017-01-01

    Thymic dendritic cells (DC) play a role in central tolerance. Three thymic DC subtypes have been described: plasmacytoid DC (pDC) and two conventional DC (cDC), CD8α+ Sirpα- DC and Sirpα+ CD8α- cDC. Both pDC and Sirpα+ cDC can take up antigen in periphery and migrate into the thymus in response t...... by CCL2 or CCR2 deficiency. Although some thymic progenitors expressed CCR2, this did not include those that give rise to pDC. Based on these results, we propose that CCR2 is involved in pDC homeostasis but its ligand CCL2 does not play a major role....

  12. Blastic plasmacytoid dendritic cell neoplasm (BPDCN): the cutaneous sanctuary.

    Science.gov (United States)

    Pileri, A; Delfino, C; Grandi, V; Agostinelli, C; Pileri, S A; Pimpinelli, N

    2012-12-01

    Blastic plasmacytoid dendritic cell neoplasm (BPDNC) is a rare tumour, which stems from plasmacytoid dendritic cells. Although the aetiology is still unclear, in the last few years various reports suggested a potential role of chromosomal aberrations in the oncogenesis. The disease is currently enclosed among "acute myeloid leukemia (AML) and related precursor neoplasms" in the last WHO classification. BPDCN has an aggressive course, however, it has been suggested that an exclusive cutaneous involvement at presentation is related to a better clinical outcome. We review the literature about BPDCN, and we present a series of 11 cases, all characterised by disease limited to the skin at presentation. Furthermore, we examined all cases of the last 10 years stored in the database of the multidisciplinary study group on cutaneous lymphomas of the University of Florence. Basing on the clinical features, patient were classified into two groups: with a single-lesion or multiple eruptive-lesions presentation. The former were treated with radiotherapy (limited field, electron beam therapy). The latter were treated with different therapeutic options, depending on age and co-morbidities. All patients with a single lesion achieved complete response. Five of 6 patients with eruptive lesions achieved a clinical response (2 complete and 3 partial response). Notably, the progression free survival was higher in the single-lesion than in the eruptive-lesion group (23 vs. 9 months). However all patients relapsed and 8 of 11 died. Although the small number of selected patients, we could speculate that the concept of "cutaneous sanctuary" is particularly true in patients with a single lesion-presentation. In these patients, especially if >70 year-old aged, radiotherapy should be encouraged as the treatment of choice.

  13. Ginseng Berry Extract Promotes Maturation of Mouse Dendritic Cells.

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    Full Text Available Ginseng extract has been shown to possess certain anti-virus, anti-tumor and immune-activating effects. However, the immunostimulatory effect of ginseng berry extract (GB has been less well characterized. In this study, we investigated the effect of GB on the activation of mouse dendritic cells (DCs in vitro and in vivo. GB treatment induced up-regulation of co-stimulatory molecules in bone marrow-derived DCs (BMDCs. Interestingly, GB induced a higher degree of co-stimulatory molecule up-regulation than ginseng root extract (GR at the same concentrations. Moreover, in vivo administration of GB promoted up-regulation of CD86, MHC class I and MHC class II and production of IL-6, IL-12 and TNF-α in spleen DCs. GB also promoted the generation of Th1 and Tc1 cells. Furthermore, Toll like receptor 4 (TLR4 and myeloid differentiation primary response 88 (MyD88 signaling pathway were essential for DC activation induced by GB. In addition, GB strongly prompted the proliferation of ovalbumin (OVA-specific CD4 and CD8 T cells. Finally, GB induced DC activation in tumor-bearing mice and the combination of OVA and GB treatment inhibited B16-OVA tumor cell growth in C57BL/6 mice. These results demonstrate that GB is a novel tumor therapeutic vaccine adjuvant by promoting DC and T cell activation.

  14. Polyelectrolyte coating of ferumoxytol nanoparticles for labeling of dendritic cells

    Energy Technology Data Exchange (ETDEWEB)

    Celikkin, Nehar; Jakubcová, Lucie; Zenke, Martin [Institute for Biomedical Engineering, Department of Cell Biology, RWTH Aachen University Hospital, Pauwelsstrasse 30, 52074 Aachen (Germany); Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Pauwelsstrasse 20, 52074 Aachen (Germany); Hoss, Mareike [Institute of Pathology, Electron Microscopy Facility, RWTH Aachen University Hospital, Pauwelsstrasse 30, 52074 Aachen (Germany); Wong, John Erik, E-mail: John.Wong@avt.rwth-aachen.de [Chemical Process Engineering, RWTH Aachen University, Turmstrasse 46, 52056 Aachen (Germany); DWI – Leibniz Institute for Interactive Materials Research, Forckenbeckstrasse 50, Aachen (Germany); Hieronymus, Thomas, E-mail: thomas.hieronymus@rwth-aachen.de [Institute for Biomedical Engineering, Department of Cell Biology, RWTH Aachen University Hospital, Pauwelsstrasse 30, 52074 Aachen (Germany); Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Pauwelsstrasse 20, 52074 Aachen (Germany)

    2015-04-15

    Engineered magnetic nanoparticles (MNPs) are emerging to be used as cell tracers, drug delivery vehicles, and contrast agents for magnetic resonance imaging (MRI) for enhanced theragnostic applications in biomedicine. In vitro labeling of target cell populations with MNPs and their implantation into animal models and patients shows promising outcomes in monitoring successful cell engraftment, differentiation and migration by using MRI. Dendritic cells (DCs) are professional antigen-presenting cells that initiate adaptive immune responses. Thus, DCs have been the focus of cellular immunotherapy and are increasingly applied in clinical trials. Here, we addressed the coating of different polyelectrolytes (PE) around ferumoxytol particles using the layer-by-layer technique. The impact of PE-coated ferumoxytol particles for labeling of DCs and Flt3{sup +} DC progenitors was then investigated. The results from our studies revealed that PE-coated ferumoxytol particles can be readily employed for labeling of DC and DC progenitors and thus are potentially suitable as contrast agents for MRI tracking.

  15. 3-bromopyruvate ameliorate autoimmune arthritis by modulating Th17/Treg cell differentiation and suppressing dendritic cell activation.

    Science.gov (United States)

    Okano, Takaichi; Saegusa, Jun; Nishimura, Keisuke; Takahashi, Soshi; Sendo, Sho; Ueda, Yo; Morinobu, Akio

    2017-02-10

    Recent studies have shown that cellular metabolism plays an important role in regulating immune cell functions. In immune cell differentiation, both interleukin-17-producing T (Th17) cells and dendritic cells (DCs) exhibit increased glycolysis through the upregulation of glycolytic enzymes, such as hexokinase-2 (HK2). Blocking glycolysis with 2-deoxyglucose was recently shown to inhibit Th17 cell differentiation while promoting regulatory T (Treg) cell generation. However, 2-DG inhibits all isoforms of HK. Thus, it is unclear which isoform has a critical role in Th17 cell differentiation and in rheumatoid arthritis (RA) pathogenesis. Here we demonstrated that 3-bromopyruvate (BrPA), a specific HK2 inhibitor, significantly decreased the arthritis scores and the histological scores in SKG mice, with a significant increase in Treg cells, decrease in Th17 cells, and decrease in activated DCs in the spleen. In vitro, BrPA facilitated the differentiation of Treg cells, suppressed Th17 cells, and inhibited the activation of DCs. These results suggested that BrPA may be a therapeutic target of murine arthritis. Although the role of IL-17 is not clarified in the treatment of RA, targeting cell metabolism to alter the immune cell functions might lead to a new therapeutic strategy for RA.

  16. Spatial distribution of excitatory synapses on the dendrites of ganglion cells in the mouse retina.

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    Yin-Peng Chen

    Full Text Available Excitatory glutamatergic inputs from bipolar cells affect the physiological properties of ganglion cells in the mammalian retina. The spatial distribution of these excitatory synapses on the dendrites of retinal ganglion cells thus may shape their distinct functions. To visualize the spatial pattern of excitatory glutamatergic input into the ganglion cells in the mouse retina, particle-mediated gene transfer of plasmids expressing postsynaptic density 95-green fluorescent fusion protein (PSD95-GFP was used to label the excitatory synapses. Despite wide variation in the size and morphology of the retinal ganglion cells, the expression of PSD95 puncta was found to follow two general rules. Firstly, the PSD95 puncta are regularly spaced, at 1-2 µm intervals, along the dendrites, whereby the presence of an excitatory synapse creates an exclusion zone that rules out the presence of other glutamatergic synaptic inputs. Secondly, the spatial distribution of PSD95 puncta on the dendrites of diverse retinal ganglion cells are similar in that the number of excitatory synapses appears to be less on primary dendrites and to increase to a plateau on higher branch order dendrites. These observations suggest that synaptogenesis is spatially regulated along the dendritic segments and that the number of synaptic contacts is relatively constant beyond the primary dendrites. Interestingly, we also found that the linear puncta density is slightly higher in large cells than in small cells. This may suggest that retinal ganglion cells with a large dendritic field tend to show an increased connectivity of excitatory synapses that makes up for their reduced dendrite density. Mapping the spatial distribution pattern of the excitatory synapses on retinal ganglion cells thus provides explicit structural information that is essential for our understanding of how excitatory glutamatergic inputs shape neuronal responses.

  17. Dendritic Cells Activate and Mature after Infection with Mycobacterium tuberculosis

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    Mamo Gezahagne

    2011-07-01

    Full Text Available Abstract Background Dendritic cells (DCs can take up an array of different antigens, including microorganisms which they can process and present more effectively than any other antigen presenting cell. However, whether the interaction between the human DC and Mycobacterium tuberculosis represents a defense mechanism by the invaded host, or helping the invader to evade the defense mechanism of the host is still not clearly understood. Findings To analyze the interactions between M. tuberculosis and immune cells, human peripheral blood monocyte-derived immature DCs were infected with M. tuberculosis H37Rv wild type strain and flow cytometry was used to analyse cell surface expression markers. The ability of the M. tuberculosis infected DC to induce T cell proliferation using 5 and 6-carboxyfluorescein diacetate succinimidyl ester (CFSE dilution technique was also investigated. DCs were found to internalize the mycobacteria and show dose dependent infection and necrosis with different multiplicity of infection. Flow cytometry analysis of cell surface expression markers CD40, CD54, CD80, CD83, CD86 and HLA DR in infected DC revealed significant (p M. tuberculosis in comparison to immature DC with no stimulation. Lipopolysaccharide (LPS from Salmonella abortus equi, a known DC maturation agent, was used as a positive control and showed a comparable up regulation of cell surface markers as observed with M. tuberculosis infected DC. It was revealed that the M. tuberculosis infected DC induced T cell proliferation. Conclusion These data clearly demonstrate that M. tuberculosis induces activation and maturation of human monocyte-derived immature DC as well as induces T cell proliferation in vitro.

  18. Regulatory T cells in skin.

    Science.gov (United States)

    Ali, Niwa; Rosenblum, Michael D

    2017-11-01

    Foxp3 + CD4 + regulatory T (Treg) cells are a subset of immune cells that function to regulate tissue inflammation. Skin is one of the largest organs and is home to a large proportion of the body's Treg cells. However, relative to other tissues (such as the spleen and gastrointestinal tract) the function of Treg cells in skin is less well defined. Here, we review our understanding of how Treg cells migrate to skin and the cellular and molecular pathways required for their maintenance in this tissue. In addition, we outline what is known about the specialized functions of Treg cells in skin. Namely, the orchestration of stem cell-mediated hair follicle regeneration, augmentation of wound healing, and promoting adaptive immune tolerance to skin commensal microbes. A comprehensive understanding of the biology of skin Treg cells may lead to novel therapeutic approaches that preferentially target these cells to treat cutaneous autoimmunity, skin cancers and disorders of skin regeneration. © 2017 John Wiley & Sons Ltd.

  19. Clec9a-Mediated Ablation of Conventional Dendritic Cells Suggests a Lymphoid Path to Generating Dendritic Cells In Vivo

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    Johanna Salvermoser

    2018-04-01

    Full Text Available Conventional dendritic cells (cDCs are versatile activators of immune responses that develop as part of the myeloid lineage downstream of hematopoietic stem cells. We have recently shown that in mice precursors of cDCs, but not of other leukocytes, are marked by expression of DNGR-1/CLEC9A. To genetically deplete DNGR-1-expressing cDC precursors and their progeny, we crossed Clec9a-Cre mice to Rosa-lox-STOP-lox-diphtheria toxin (DTA mice. These mice develop signs of age-dependent myeloproliferative disease, as has been observed in other DC-deficient mouse models. However, despite efficient depletion of cDC progenitors in these mice, cells with phenotypic characteristics of cDCs populate the spleen. These cells are functionally and transcriptionally similar to cDCs in wild type control mice but show somatic rearrangements of Ig-heavy chain genes, characteristic of lymphoid origin cells. Our studies reveal a previously unappreciated developmental heterogeneity of cDCs and suggest that the lymphoid lineage can generate cells with features of cDCs when myeloid cDC progenitors are impaired.

  20. DMPD: Proximal effects of Toll-like receptor activation in dendritic cells. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 17142025 Proximal effects of Toll-like receptor activation in dendritic cells. Watt...) (.svg) (.html) (.csml) Show Proximal effects of Toll-like receptor activation in dendritic cells. PubmedID... 17142025 Title Proximal effects of Toll-like receptor activation in dendritic ce

  1. Neurotrophin Receptor p75NTR Regulates Immune Function of Plasmacytoid Dendritic Cells

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    Joanna Bandoła

    2017-08-01

    Full Text Available Plasmacytoid dendritic cells (pDCs regulate innate and adaptive immunity. Neurotrophins and their receptors control the function of neuronal tissue. In addition, they have been demonstrated to be part of the immune response but little is known about the effector immune cells involved. We report, for the first time, the expression and immune-regulatory function of the low affinity neurotrophin receptor p75 neurotrophin receptor (p75NTR by the antigen-presenting pDCs, mediated by toll-like receptor (TLR 9 activation and differential phosphorylation of interferon regulatory factor 3 and 7. The modulation of p75NTR on pDCs significantly influences disease progression of asthma in an ovalbumin-induced mouse model mediated by the TLR9 signaling pathway. p75NTR activation of pDCs from patients with asthma increased allergen-specific T cell proliferation and cytokine secretion in nerve growth factor concentration-dependent manner. Further, p75NTR activation of pDCs delayed the onset of autoimmune diabetes in RIP-CD80GP mice and aggravated graft-versus-host disease in a xenotransplantation model. Thus, p75NTR signaling on pDCs constitutes a new and critical mechanism connecting neurotrophin signaling and immune response regulation with great therapeutic potential for a variety of immune disorders.

  2. Neurotrophin Receptor p75NTR Regulates Immune Function of Plasmacytoid Dendritic Cells.

    Science.gov (United States)

    Bandoła, Joanna; Richter, Cornelia; Ryser, Martin; Jamal, Arshad; Ashton, Michelle P; von Bonin, Malte; Kuhn, Matthias; Dorschner, Benjamin; Alexopoulou, Dimitra; Navratiel, Katrin; Roeder, Ingo; Dahl, Andreas; Hedrich, Christian M; Bonifacio, Ezio; Brenner, Sebastian; Thieme, Sebastian

    2017-01-01

    Plasmacytoid dendritic cells (pDCs) regulate innate and adaptive immunity. Neurotrophins and their receptors control the function of neuronal tissue. In addition, they have been demonstrated to be part of the immune response but little is known about the effector immune cells involved. We report, for the first time, the expression and immune-regulatory function of the low affinity neurotrophin receptor p75 neurotrophin receptor (p75NTR) by the antigen-presenting pDCs, mediated by toll-like receptor (TLR) 9 activation and differential phosphorylation of interferon regulatory factor 3 and 7. The modulation of p75NTR on pDCs significantly influences disease progression of asthma in an ovalbumin-induced mouse model mediated by the TLR9 signaling pathway. p75NTR activation of pDCs from patients with asthma increased allergen-specific T cell proliferation and cytokine secretion in nerve growth factor concentration-dependent manner. Further, p75NTR activation of pDCs delayed the onset of autoimmune diabetes in RIP-CD80GP mice and aggravated graft-versus-host disease in a xenotransplantation model. Thus, p75NTR signaling on pDCs constitutes a new and critical mechanism connecting neurotrophin signaling and immune response regulation with great therapeutic potential for a variety of immune disorders.

  3. Effects of Mycoplasma hyopneumoniae on porcine nasal cavity dendritic cells.

    Science.gov (United States)

    Shen, Yumeng; Hu, Weiwei; Wei, Yanna; Feng, Zhixin; Yang, Qian

    2017-01-01

    Mycoplasma hyopneumoniae (Mhp) is the primary etiological agent responsible for swine enzootic pneumonia (EP), a disease that cause tremendous economic losses all over the swine industry. Dendritic cells (DCs), the most effective antigen-presenting cells, are widely distributed beneath respiratory epithelium. DCs uptake and present antigens to T cells, to initiate protective immune responses or generate immune-mediated pathology in different infections. In this study, we investigated the changes in the different DCs subpopulations, T cells and SIgA positive cells counts in porcine nasal cavity after long time Mhp infection. We further evaluated the role of porcine DCs in Mhp exposure. Our results showed that the number of SLA-II-DR + SWC3a + DCs, SLA-II-DR + CD11b + DCs, T cells, SIgA positive cells in nasal cavity were decreased after Mhp 28 days infection in vivo experiment. The antigen presenting ability of DCs were inhibited by Mhp exposure. DCs couldn't activate T-cell proliferation by down-regulating the antigen presenting molecule CD1a expression and promoting high level of IL-10 production. Further more, the expression levels of IL-12 and IFN-γ in DCs were decreased, suggesting that DCs favour for Th2 immune response development after Mhp exposure in vitro. Taken together, Mhp infection impairs the immune function which allows the persistence of Mhp and cause predispose pigs to secondary infections. The decline of DCs presentation ability is the reason why dysfunction and persistence in Mhp infection. These findings are benefit for exploring the pathogenic mechanisms of Mhp in pigs. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Modulation of Dendritic Cell Responses by Parasites: A Common Strategy to Survive

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    César A. Terrazas

    2010-01-01

    Full Text Available Parasitic infections are one of the most important causes of morbidity and mortality in our planet and the immune responses triggered by these organisms are critical to determine their outcome. Dendritic cells are key elements for the development of immunity against parasites; they control the responses required to eliminate these pathogens while maintaining host homeostasis. However, there is evidence showing that parasites can influence and regulate dendritic cell function in order to promote a more permissive environment for their survival. In this review we will focus on the strategies protozoan and helminth parasites have developed to interfere with dendritic cell activities as well as in the possible mechanisms involved.

  5. Unimpaired dendritic cell functions in MVP/LRP knockout mice.

    Science.gov (United States)

    Mossink, Marieke H; de Groot, Jan; van Zon, Arend; Fränzel-Luiten, Erna; Schoester, Martijn; Scheffer, George L; Sonneveld, Pieter; Scheper, Rik J; Wiemer, Erik A C

    2003-09-01

    Dendritic cells (DCs) act as mobile sentinels of the immune system. By stimulating T lymphocytes, DCs are pivotal for the initiation of both T- and B-cell-mediated immune responses. Recently, ribonucleoprotein particles (vaults) were found to be involved in the development and/or function of human DCs. To further investigate the role of vaults in DCs, we examined the effects of disruption of the major vault protein (MVP/LRP) on the development and antigen-presenting capacity of DCs, using our MVP/LRP knockout mouse model. Mononuclear bone marrow cells were isolated from wild-type and knockout mice and stimulated to differentiate to DCs. Like human DCs, the wild-type murine DC cultures strongly expressed MVP/LRP. Nevertheless, the MVP/LRP-deficient DCs developed normally and showed similar expression levels of several DC surface markers. No differences were observed in in vitro studies on the antigen uptake and presenting capacities of the wild-type and MVP/LRP knockout DCs. Moreover, immunization of the MVP/LRP-deficient mice with several T-cell antigens led to responses similar to those observed in the wild-type mice, indicating that the in vivo DC migration and antigen-presentation capacities are intact. Moreover, no differences were observed in the induction of the T cell-dependent humoral responses and orally induced peripheral T-cell tolerance. In conclusion, vaults are not required for primary DC functions. Their abundance in DCs may, however, still reflect basic roles in myeloid cell proliferation and DC development.

  6. 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

    2014-01-01

    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. PMID:24273170

  7. Dendritic cells modulate burn wound healing by enhancing early proliferation.

    Science.gov (United States)

    Vinish, Monika; Cui, Weihua; Stafford, Eboni; Bae, Leon; Hawkins, Hal; Cox, Robert; Toliver-Kinsky, Tracy

    2016-01-01

    Adequate wound healing is vital for burn patients to reduce the risk of infections and prolonged hospitalization. Dendritic cells (DCs) are antigen presenting cells that release cytokines and are central for the activation of innate and acquired immune responses. Studies have showed their presence in human burn wounds; however, their role in burn wound healing remains to be determined. This study investigated the role of DCs in modulating healing responses within the burn wound. A murine model of full-thickness contact burns was used to study wound healing in the absence of DCs (CD11c promoter-driven diphtheria toxin receptor transgenic mice) and in a DC-rich environment (using fms-like tyrosine kinase-3 ligand, FL- a DC growth factor). Wound closure was significantly delayed in DC-deficient mice and was associated with significant suppression of early cellular proliferation, granulation tissue formation, wound levels of TGFβ1 and formation of CD31+ vessels in healing wounds. In contrast, DC enhancement significantly accelerated early wound closure, associated with increased and accelerated cellular proliferation, granulation tissue formation, and increased TGFβ1 levels and CD31+ vessels in healing wounds. We conclude that DCs play an important role in the acceleration of early wound healing events, likely by secreting factors that trigger the proliferation of cells that mediate wound healing. Therefore, pharmacological enhancement of DCs may provide a therapeutic intervention to facilitate healing of burn wounds. © 2016 by the Wound Healing Society.

  8. Priming anticancer active specific immunotherapy with dendritic cells.

    Science.gov (United States)

    Mocellin, Simone

    2005-06-01

    Dendritic cells (DCs) probably represent the most powerful naturally occurring immunological adjuvant for anticancer vaccines. However, the initial enthusiasm for DC-based vaccines is being tempered by clinical results not meeting expectations. The partial failure of current vaccine formulations is explained by the extraordinary complexity of the immune system, which makes the task of exploiting the potential of such a biotherapeutic approach highly challenging. Clinical findings obtained in humans so far indicate that the immune system can be actively polarized against malignant cells by means of DC-based active specific immunotherapy, and that in some cases this is associated with tumor regression. This implies that under some unique circumstances, the naturally 'dormant' immune effectors can actually be employed as endogenous weapons against malignant cells. Only the thorough understanding of DC biology and tumor-host immune system interactions will allow researchers to reproduce, in a larger set of patients, the cellular/molecular conditions leading to an effective immune-mediated eradication of cancer.

  9. HIV-derived vectors for gene therapy targeting dendritic cells.

    Science.gov (United States)

    Rossetti, Maura; Cavarelli, Mariangela; Gregori, Silvia; Scarlatti, Gabriella

    2013-01-01

    Human immunodeficiency virus type 1 (HIV-1)-derived lentiviral vectors (LV) have the potential to mediate stable therapeutic gene transfer. However, similarly to other viral vectors, their benefit is compromised by the induction of an immune response toward transgene-expressing cells that closely mimics antiviral immunity. LV share with the parental HIV the ability to activate dendritic cells (DC), while lack the peculiar ability of subverting DC functions, which is responsible for HIV immune escape. Understanding the interaction between LV and DC, with plasmacytoid and myeloid DC playing fundamental and distinct roles, has paved the way to novel approaches aimed at regulating transgene-specific immune responses. Thanks to the ability to target either DC subsets LV might be a powerful tool to induce immunity (i.e., gene therapy of cancer), cell death (i.e., in HIV/AIDS infection), or tolerance (i.e., gene therapy strategies for monogenic diseases). In this chapter, similarities and differences between the LV-mediated and HIV-mediated induction of immune responses, with specific focus on their interactions with DC, are discussed.

  10. Synthetic and biogenic magnetite nanoparticles for tracking of stem cells and dendritic cells

    International Nuclear Information System (INIS)

    Schwarz, Sebastian; Fernandes, Fabiana; Sanroman, Laura; Hodenius, Michael; Lang, Claus; Himmelreich, Uwe; Schmitz-Rode, Thomas; Schueler, Dirk; Hoehn, Mathias

    2009-01-01

    Accurate delivery of cells to target organs is critical for success of cell-based therapies with stem cells or immune cells such as antigen-presenting dendritic cells (DC). Labeling with contrast agents before implantation provides a powerful means for monitoring cellular migration using magnetic resonance imaging (MRI). In this study, we investigated the uptake of fully synthesized or bacterial magnetic nanoparticles (MNPs) into hematopoietic Flt3 + stem cells and DC from mouse bone marrow. We show that (i) uptake of both synthetic and biogenic nanoparticles into cells endow magnetic activity and (ii) low numbers of MNP-loaded cells are readily detected by MRI.

  11. A dendrite-autonomous mechanism for direction selectivity in retinal starburst amacrine cells.

    Science.gov (United States)

    Hausselt, Susanne E; Euler, Thomas; Detwiler, Peter B; Denk, Winfried

    2007-07-01

    Detection of image motion direction begins in the retina, with starburst amacrine cells (SACs) playing a major role. SACs generate larger dendritic Ca(2+) signals when motion is from their somata towards their dendritic tips than for motion in the opposite direction. To study the mechanisms underlying the computation of direction selectivity (DS) in SAC dendrites, electrical responses to expanding and contracting circular wave visual stimuli were measured via somatic whole-cell recordings and quantified using Fourier analysis. Fundamental and, especially, harmonic frequency components were larger for expanding stimuli. This DS persists in the presence of GABA and glycine receptor antagonists, suggesting that inhibitory network interactions are not essential. The presence of harmonics indicates nonlinearity, which, as the relationship between harmonic amplitudes and holding potential indicates, is likely due to the activation of voltage-gated channels. [Ca(2+)] changes in SAC dendrites evoked by voltage steps and monitored by two-photon microscopy suggest that the distal dendrite is tonically depolarized relative to the soma, due in part to resting currents mediated by tonic glutamatergic synaptic input, and that high-voltage-activated Ca(2+) channels are active at rest. Supported by compartmental modeling, we conclude that dendritic DS in SACs can be computed by the dendrites themselves, relying on voltage-gated channels and a dendritic voltage gradient, which provides the spatial asymmetry necessary for direction discrimination.

  12. A dendrite-autonomous mechanism for direction selectivity in retinal starburst amacrine cells.

    Directory of Open Access Journals (Sweden)

    Susanne E Hausselt

    2007-07-01

    Full Text Available Detection of image motion direction begins in the retina, with starburst amacrine cells (SACs playing a major role. SACs generate larger dendritic Ca(2+ signals when motion is from their somata towards their dendritic tips than for motion in the opposite direction. To study the mechanisms underlying the computation of direction selectivity (DS in SAC dendrites, electrical responses to expanding and contracting circular wave visual stimuli were measured via somatic whole-cell recordings and quantified using Fourier analysis. Fundamental and, especially, harmonic frequency components were larger for expanding stimuli. This DS persists in the presence of GABA and glycine receptor antagonists, suggesting that inhibitory network interactions are not essential. The presence of harmonics indicates nonlinearity, which, as the relationship between harmonic amplitudes and holding potential indicates, is likely due to the activation of voltage-gated channels. [Ca(2+] changes in SAC dendrites evoked by voltage steps and monitored by two-photon microscopy suggest that the distal dendrite is tonically depolarized relative to the soma, due in part to resting currents mediated by tonic glutamatergic synaptic input, and that high-voltage-activated Ca(2+ channels are active at rest. Supported by compartmental modeling, we conclude that dendritic DS in SACs can be computed by the dendrites themselves, relying on voltage-gated channels and a dendritic voltage gradient, which provides the spatial asymmetry necessary for direction discrimination.

  13. Regulation of TGFβ in the immune system: an emerging role for integrins and dendritic cells.

    Science.gov (United States)

    Worthington, John J; Fenton, Thomas M; Czajkowska, Beata I; Klementowicz, Joanna E; Travis, Mark A

    2012-12-01

    Regulation of an immune response requires complex crosstalk between cells of the innate and adaptive immune systems, via both cell-cell contact and secretion of cytokines. An important cytokine with a broad regulatory role in the immune system is transforming growth factor-β (TGF-β). TGF-β is produced by and has effects on many different cells of the immune system, and plays fundamental roles in the regulation of immune responses during homeostasis, infection and disease. Although many cells can produce TGFβ, it is always produced as an inactive complex that must be activated to bind to the TGFβ receptor complex and promote downstream signalling. Thus, regulation of TGFβ activation is a crucial step in controlling TGFβ function. This review will discuss how TGFβ controls diverse immune responses and how TGFβ function is regulated, with a focus on recent work highlighting a critical role for the integrin αvβ8 expressed by dendritic cells in activating TGFβ. Copyright © 2012 Elsevier GmbH. All rights reserved.

  14. The role of CD103+ Dendritic cells in the intestinal mucosal immune system.

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    Darren Thomas Ruane

    2011-07-01

    Full Text Available While dendritic cells (DC are central to the induction and regulation of adaptive immunity, these cells are very heterogenous and specific subsets can be characterized based on the expression of cell surface markers and functional properties. Intestinal CD103+ DCs are the subject of particular interest due to their role in regulating mucosal immunity. Since the epithelial surfaces are constantly exposed to a high antigenic load, tight regulation of innate and adaptive intestinal immune responses is vital as intestinal inflammation can have detrimental consequences for the host. Strategically positioned within the lamina propria, CD103+ DCs play an important role in maintaining intestinal immune homeostasis. These cells are required for the induction of tolerogenic immune responses and imprinting gut homing phenotypic changes on antigen-specific T cells. Recent insights into their development and regulatory properties have revealed additional immunoregulatory roles and further highlighted their importance for intestinal immunity. In this review we discuss the nature of the intestinal CD103+ DC population and the emerging roles of these cells in the regulation of mucosal immunity.

  15. Metabolic Control of Dendritic Cell Activation and Function: Recent Advances and Clinical Implications

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    Bart eEverts

    2014-05-01

    Full Text Available Dendritic cells (DCs are key regulators of both immunity and tolerance by controlling activation and polarization of effector T helper cell and regulatory T cell responses. Therefore, there is a major focus on developing approaches to manipulate DC function for immunotherapy. It is well known that changes in cellular activation are coupled to profound changes in cellular metabolism. Over the past decade there is a growing appreciation that these metabolic changes also underlie the capacity of immune cells to perform particular functions. This has led to the concept that the manipulation of cellular metabolism can be used to shape innate and adaptive immune responses. While most of our understanding in this area has been gained from studies with T cells and macrophages, evidence is emerging that the activation and function of DCs are also dictated by the type of metabolism these cells commit to. We here discuss these new insights and explore whether targeting of metabolic pathways in DCs could hold promise as a novel approach to manipulate the functional properties of DCs for clinical purposes.

  16. p16 expression in follicular dendritic cell sarcoma: a potential mimicker of human papillomavirus-related oropharyngeal squamous cell carcinoma.

    Science.gov (United States)

    Zhang, Lingxin; Yang, Chen; Lewis, James S; El-Mofty, Samir K; Chernock, Rebecca D

    2017-08-01

    Follicular dendritic cell sarcoma is a rare mesenchymal neoplasm that most commonly occurs in cervical lymph nodes. It has histologic and clinical overlap with the much more common p16-positive human papillomavirus (HPV)-related squamous cell carcinoma of the oropharynx, which characteristically has nonkeratinizing morphology and often presents as an isolated neck mass. Not surprisingly, follicular dendritic cell sarcomas are commonly misdiagnosed as squamous cell carcinoma. Immunohistochemistry is helpful in separating the 2 entities. Follicular dendritic cell sarcoma expresses dendritic markers such as CD21 and CD23 and is almost always cytokeratin negative. However, in many cases of HPV-related oropharyngeal carcinoma, only p16 immunohistochemistry as a prognostic and surrogate marker for HPV is performed. p16 expression in follicular dendritic cell sarcoma has not been characterized. Here, we investigate the expression of p16 in follicular dendritic cell sarcoma and correlate it with retinoblastoma protein expression. A pilot study of dendritic marker expression in HPV-related oropharyngeal squamous cell carcinoma was also performed. We found that 4 of 8 sarcomas expressed p16 with strong and diffuse staining in 2 cases. In 2 of the 4 cases, p16 expression corresponded to loss of retinoblastoma protein expression. Dendritic marker expression (CD21 and CD23) was not found in HPV-related oropharyngeal squamous cell carcinomas. As such, positive p16 immunohistochemistry cannot be used as supportive evidence for the diagnosis of squamous cell carcinoma as strong and diffuse p16 expression may also occur in follicular dendritic cell sarcoma. Cytokeratins and dendritic markers are critical in separating the two tumor types. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Exploiting the role of endogenous lymphoid-resident dendritic cells in the priming of NKT cells and CD8+ T cells to dendritic cell-based vaccines.

    Directory of Open Access Journals (Sweden)

    Troels R Petersen

    2011-03-01

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

  18. Dendritic-cell control of pathogen-driven T-cell polarization

    NARCIS (Netherlands)

    Kapsenberg, Martien L.

    2003-01-01

    Dendritic cells (DCs) are central in the orchestration of the various forms of immunity and tolerance. Their immunoregulatory role mainly relies on the ligation of specific receptors that initiate and modulate DC maturation resulting in the development of functionally different effector DC subsets

  19. Neuromelanin is an immune stimulator for dendritic cells in vitro

    Directory of Open Access Journals (Sweden)

    Oberländer Uwe

    2011-11-01

    Full Text Available Abstract Background Parkinson's disease (PD is characterized at the cellular level by a destruction of neuromelanin (NM-containing dopaminergic cells and a profound reduction in striatal dopamine. It has been shown recently that anti-melanin antibodies are increased in sera of Parkinson patients, suggesting that NM may act as an autoantigen. In this study we tested whether NM is being recognized by dendritic cells (DCs, the major cell type for inducing T- and B-cell responses in vivo. This recognition of NM by DCs is a prerequisite to trigger an adaptive autoimmune response directed against NM-associated structures. Results Murine DCs were treated with NM of substantia nigra (SN from human subjects or with synthetic dopamine melanin (DAM. DCs effectively phagocytized NM and subsequently developed a mature phenotype (CD86high/MHCIIhigh. NM-activated DCs secreted the proinflammatory cytokines IL-6 and TNF-α. In addition, they potently triggered T cell proliferation in a mixed lymphocyte reaction, showing that DC activation was functional to induce a primary T cell response. In contrast, DAM, which lacks the protein and lipid components of NM but mimics the dopamine-melanin backbone of NM, had only very little effect on DC phenotype and function. Conclusions NM is recognized by DCs in vitro and triggers their maturation. If operative in vivo, this would allow the DC-mediated transport and presentation of SN antigens to the adaptive immune system, leading to autoimmmunity in susceptible individuals. Our data provide a rationale for an autoimmune-based pathomechanism of PD with NM as the initial trigger.

  20. Bortezomib as a new therapeutic approach for blastic plasmacytoid dendritic cell neoplasm.

    Science.gov (United States)

    Philippe, Laure; Ceroi, Adam; Bôle-Richard, Elodie; Jenvrin, Alizée; Biichle, Sabeha; Perrin, Sophie; Limat, Samuel; Bonnefoy, Francis; Deconinck, Eric; Saas, Philippe; Garnache-Ottou, Francine; Angelot-Delettre, Fanny

    2017-11-01

    Blastic plasmacytoid dendritic cell neoplasm is an aggressive hematologic malignancy with a poor prognosis. No consensus regarding optimal treatment modalities is currently available. Targeting the nuclear factor-kappa B pathway is considered a promising approach since blastic plasmacytoid dendritic cell neoplasm has been reported to exhibit constitutive activation of this pathway. Moreover, nuclear factor-kappa B inhibition in blastic plasmacytoid dendritic cell neoplasm cell lines, achieved using either an experimental specific inhibitor JSH23 or the clinical drug bortezomib, interferes in vitro with leukemic cell proliferation and survival. Here we extended these data by showing that primary blastic plasmacytoid dendritic cell neoplasm cells from seven patients were sensitive to bortezomib-induced cell death. We confirmed that bortezomib efficiently inhibits the phosphorylation of the RelA nuclear factor-kappa B subunit in blastic plasmacytoid dendritic cell neoplasm cell lines and primary cells from patients in vitro and in vivo in a mouse model. We then demonstrated that bortezomib can be associated with other drugs used in different chemotherapy regimens to improve its impact on leukemic cell death. Indeed, when primary blastic plasmacytoid dendritic cell neoplasm cells from a patient were grafted into mice, bortezomib treatment significantly increased the animals' survival, and was associated with a significant decrease of circulating leukemic cells and RelA nuclear factor-kappa B subunit expression. Overall, our results provide a rationale for the use of bortezomib in combination with other chemotherapy for the treatment of patients with blastic plasmacytoid dendritic cell neoplasm. Based on our data, a prospective clinical trial combining proteasome inhibitor with classical drugs could be envisaged. Copyright© Ferrata Storti Foundation.

  1. Mannan-MUC1-pulsed dendritic cell immunotherapy: a phase I trial in patients with adenocarcinoma.

    Science.gov (United States)

    Loveland, Bruce E; Zhao, Anne; White, Shane; Gan, Hui; Hamilton, Kate; Xing, Pei-Xiang; Pietersz, Geoffrey A; Apostolopoulos, Vasso; Vaughan, Hilary; Karanikas, Vaios; Kyriakou, Peter; McKenzie, Ian F C; Mitchell, Paul L R

    2006-02-01

    Tumor antigen-loaded dendritic cells show promise for cancer immunotherapy. This phase I study evaluated immunization with autologous dendritic cells pulsed with mannan-MUC1 fusion protein (MFP) to treat patients with advanced malignancy. Eligible patients had adenocarcinoma expressing MUC1, were of performance status 0 to 1, with no autoimmune disease. Patients underwent leukapheresis to generate dendritic cells by culture ex vivo with granulocyte macrophage colony-stimulating factor and interleukin 4 for 5 days. Dendritic cells were then pulsed overnight with MFP and harvested for reinjection. Patients underwent three cycles of leukapheresis and reinjection at monthly intervals. Patients with clinical benefit were able to continue with dendritic cell-MFP immunotherapy. Ten patients with a range of tumor types were enrolled, with median age of 60 years (range, 33-70 years); eight patients were of performance status 0 and two of performance status 1. Dendritic cell-MFP therapy led to strong T-cell IFNgamma Elispot responses to the vaccine and delayed-type hypersensitivity responses at injection sites in nine patients who completed treatments. Immune responses were sustained at 1 year in monitored patients. Antibody responses were seen in three patients only and were of low titer. Side effects were grade 1 only. Two patients with clearly progressive disease (ovarian and renal carcinoma) at entry were stable after initial therapy and went on to further leukapheresis and dendritic cell-MFP immunotherapy. These two patients have now each completed over 3 years of treatment. Immunization produced T-cell responses in all patients with evidence of tumor stabilization in 2 of the 10 advanced cancer patients treated. These data support further clinical evaluation of this dendritic cell-MFP immunotherapy.

  2. Natural Killer Dendritic Cells Enhance Immune Responses Elicited by α-Galactosylceramide-Stimulated Natural Killer T Cells

    Directory of Open Access Journals (Sweden)

    Sung Won Lee

    2013-01-01

    Full Text Available Natural killer dendritic cells (NKDCs possess potent anti-tumor activity, but the cellular effect of NKDC interactions with other innate immune cells is unclear. In this study, we demonstrate that the interaction of NKDCs and natural killer T (NKT cells is required for the anti-tumor immune responses that are elicited by α-galactosylceramide (α-GC in mice. The rapid and strong expression of interferon-γ by NKDCs after α-GC stimulation was dependent on NKT cells. Various NK and DC molecular markers and cytotoxic molecules were up-regulated following α-GC administration. This up-regulation could improve NKDC presentation of tumor antigens and increase cytotoxicity against tumor cells. NKDCs were required for the stimulation of DCs, NK cells, and NKT cells. The strong anti-tumor immune responses elicited by α-GC may be due to the down-regulation of regulatory T cells. Furthermore, the depletion of NKDCs dampened the tumor clearance mediated by α-GC-stimulated NKT cells in vivo. Taken together, these results indicate that complex interactions of innate immune cells might be required to achieve optimal anti-tumor immune responses during the early stages of tumorigenesis.

  3. Effects of mesenchymal stem cells from human induced pluripotent stem cells on differentiation, maturation, and function of dendritic cells.

    Science.gov (United States)

    Gao, Wen-Xiang; Sun, Yue-Qi; Shi, Jianbo; Li, Cheng-Lin; Fang, Shu-Bin; Wang, Dan; Deng, Xue-Quan; Wen, Weiping; Fu, Qing-Ling

    2017-03-02

    Mesenchymal stem cells (MSCs) have potent immunomodulatory effects on multiple immune cells and have great potential in treating immune disorders. Induced pluripotent stem cells (iPSCs) serve as an unlimited and noninvasive source of MSCs, and iPSC-MSCs have been reported to have more advantages and exhibit immunomodulation on T lymphocytes and natural killer cells. However, the effects of iPSC-MSCs on dendritic cells (DCs) are unclear. The aim of this study is to investigate the effects of iPSC-MSCs on the differentiation, maturation, and function of DCs. Human monocyte-derived DCs were induced and cultured in the presence or absence of iPSC-MSCs. Flow cytometry was used to analyze the phenotype and functions of DCs, and enzyme-linked immunosorbent assay (ELISA) was used to study cytokine production. In this study, we successfully induced MSCs from different clones of human iPSCs. iPSC-MSCs exhibited a higher proliferation rate with less cell senescence than BM-MSCs. iPSC-MSCs inhibited the differentiation of human monocyte-derived DCs by both producing interleukin (IL)-10 and direct cell contact. Furthermore, iPSC-MSCs did not affect immature DCs to become mature DCs, but modulated their functional properties by increasing their phagocytic ability and inhibiting their ability to stimulate proliferation of lymphocytes. More importantly, iPSC-MSCs induced the generation of IL-10-producing regulatory DCs in the process of maturation, which was mostly mediated by a cell-cell contact mechanism. Our results indicate an important role for iPSC-MSCs in the modulation of DC differentiation and function, supporting the clinical application of iPSC-MSCs in DC-mediated immune diseases.

  4. Glycan Sulfation Modulates Dendritic Cell Biology and Tumor Growth

    Directory of Open Access Journals (Sweden)

    Roland El Ghazal

    2016-05-01

    Full Text Available In cancer, proteoglycans have been found to play roles in facilitating the actions of growth factors, and effecting matrix invasion and remodeling. However, little is known regarding the genetic and functional importance of glycan chains displayed by proteoglycans on dendritic cells (DCs in cancer immunity. In lung carcinoma, among other solid tumors, tumor-associated DCs play largely subversive/suppressive roles, promoting tumor growth and progression. Herein, we show that targeting of DC glycan sulfation through mutation in the heparan sulfate biosynthetic enzyme N-deacetylase/N-sulfotransferase-1 (Ndst1 in mice increased DC maturation and inhibited trafficking of DCs to draining lymph nodes. Lymphatic-driven DC migration and chemokine (CCL21-dependent activation of a major signaling pathway required for DC migration (as measured by phospho-Akt were sensitive to Ndst1 mutation in DCs. Lewis lung carcinoma tumors in mice deficient in Ndst1 were reduced in size. Purified CD11c+ cells from the tumors, which contain the tumor-infiltrating DC population, showed a similar phenotype in mutant cells. These features were replicated in mice deficient in syndecan-4, the major heparan sulfate proteoglycan expressed on the DC surface: Tumors were growth-impaired in syndecan-4–deficient mice and were characterized by increased infiltration by mature DCs. Tumors on the mutant background also showed greater infiltration by NK cells and NKT cells. These findings indicate the genetic importance of DC heparan sulfate proteoglycans in tumor growth and may guide therapeutic development of novel strategies to target syndecan-4 and heparan sulfate in cancer.

  5. Quantitative Determination of Ceramide Molecular Species in Dendritic Cells

    Directory of Open Access Journals (Sweden)

    Samar Al Makdessi

    2016-09-01

    Full Text Available Background/Aims: The activation of acid sphingomyelinase by cellular stress or receptors or the de novo synthesis lead to the formation of ceramide (N-acylsphingosine, which in turn modifies the biophysical properties of cellular membrane and greatly amplifies the intensity of the initial signal. Ceramide, which acts by re-organizing a given signalosome rather than being a second messenger, has many functions in infection biology, cancer, cardiovascular syndromes, and immune regulation. Experimental studies on the infection of human cells with different bacterial agents demonstrated the activation of the acid sphingomyelinase/ceramide system. Moreover, the release of ceramide was found to be a requisite for the uptake of the pathogen. Considering the particular importance of the cellular role of ceramide, it was necessary to develop sensitive and accurate methods for its quantification. Methods: Here, we describe a method quantifying ceramide in dendritic cells and defining the different fatty acids (FA bound to sphingosine. The main steps of the method include extraction of total lipids, separation of the ceramide by thin-layer chromatography, derivatization of ceramide-fatty acids (Cer-FA, and quantitation of these acids in their methyl form by gas chromatography on polar capillary columns. The identification of FA was achieved by means of known standards and confirmed by mass spectrometry. Results: FA ranging between C10 and C24 could be detected and quantified. The concentration of the sum of Cer-FA amounted to 14.88 ± 8.98 nmol/106 cells (n=10. Oleic acid, which accounted for approximately half of Cer-FA (7.73 ± 6.52 nmol/106 cells was the predominant fatty acid followed by palmitic acid (3.47 ± 1.54 nmol/106 cells. Conclusion: This highly sensitive method allows the quantification of different molecular species of ceramides.

  6. Vaccines with dendritic cells in prostate cancer patients

    International Nuclear Information System (INIS)

    Kvalheim, G.

    2004-01-01

    It has been shown that autologous D Cs pulsed with peptides specific for prostate specific Ag (PSA) or prostate-specific membrane Ag are capable of stimulating potent CT L in vitro. However there is evidence to believe that multiple tumour derived antigens would be more potent to elicit anti-tumour responses. Based on these observations a Phase I/II clinical trial in has been initiated. Autologous monocyte-derived dendritic cells (DC s) were transfected with mRNA from three prostate cancer cell lines (DU145, LNCaP and P C-3) and used for vaccination. Twenty patients have been enrolled and 19 have finished vaccination. Each patient received at least four weekly injections. Of them, 10 patients were vaccinated intranodally under ultrasonic guidance and 9 others received the vaccine intradermally. Safety and feasibility were evaluated. No evidence of toxicity and adverse events was observed. Immune response was measured as DTH and by vitro immunoassays including ELISPOT, T cell proliferation test and cytotoxicity test in pre- and post-vaccination peripheral blood samples. Twelve patients developed a specific immune response to tumour cells. Ten patients showed a significant decrease in log slope PSA. Patients with lower PSA tend to give a better response. The early clinical outcome was significantly related to immune responses (p<0.05). We conclude that the strategy of vaccinating with mRNA transfected D Cs functions to elicit cellular immune responses specific for antigens associated with prostate cancer cells and such responses may result in a clinical benefit for the patients

  7. Biotin deficiency enhances the inflammatory response of human dendritic cells.

    Science.gov (United States)

    Agrawal, Sudhanshu; Agrawal, Anshu; Said, Hamid M

    2016-09-01

    The water-soluble biotin (vitamin B7) is indispensable for normal human health. The vitamin acts as a cofactor for five carboxylases that are critical for fatty acid, glucose, and amino acid metabolism. Biotin deficiency is associated with various diseases, and mice deficient in this vitamin display enhanced inflammation. Previous studies have shown that biotin affects the functions of adaptive immune T and NK cells, but its effect(s) on innate immune cells is not known. Because of that and because vitamins such as vitamins A and D have a profound effect on dendritic cell (DC) function, we investigated the effect of biotin levels on the functions of human monocyte-derived DCs. Culture of DCs in a biotin-deficient medium (BDM) and subsequent activation with LPS resulted in enhanced secretion of the proinflammatory cytokines TNF-α, IL-12p40, IL-23, and IL-1β compared with LPS-activated DCs cultured in biotin-sufficient (control) and biotin-oversupplemented media. Furthermore, LPS-activated DCs cultured in BDM displayed a significantly higher induction of IFN-γ and IL-17 indicating Th1/Th17 bias in T cells compared with cells maintained in biotin control or biotin-oversupplemented media. Investigations into the mechanisms suggested that impaired activation of AMP kinase in DCs cultured in BDM may be responsible for the observed increase in inflammatory responses. In summary, these results demonstrate for the first time that biotin deficiency enhances the inflammatory responses of DCs. This may therefore be one of the mechanism(s) that mediates the observed inflammation that occurs in biotin deficiency.

  8. Diesel-Enriched Particulate Matter Functionally Activates Human Dendritic Cells

    Science.gov (United States)

    Porter, Michael; Karp, Matthew; Killedar, Smruti; Bauer, Stephen M.; Guo, Jia; Williams, D'Ann; Breysse, Patrick; Georas, Steve N.; Williams, Marc A.

    2007-01-01

    Epidemiologic studies have associated exposure to airborne particulate matter (PM) with exacerbations of asthma. It is unknown how different sources of PM affect innate immunity. We sought to determine how car- and diesel exhaust–derived PM affects dendritic cell (DC) activation. DC development was modeled using CD34+ hematopoietic progenitors. Airborne PM was collected from exhaust plenums of Fort McHenry Tunnel providing car-enriched particles (CEP) and diesel-enriched particles (DEP). DC were stimulated for 48 hours with CEP, DEP, CD40-ligand, or lipopolysaccharide. DC activation was assessed by flow cytometry, enzyme-linked immunosorbent assay, and standard culture techniques. DEP increased uptake of fluorescein isothiocyanate–dextran (a model antigen) by DC. Diesel particles enhanced cell-surface expression of co-stimulatory molecules (e.g., CD40 [P < 0.01] and MHC class II [P < 0.01]). By contrast, CEP poorly affected antigen uptake and expression of cell surface molecules, and did not greatly affect cytokine secretion by DC. However, DEP increased production of TNF, IL-6, and IFN-γ (P < 0.01), IL-12 (P < 0.05), and vascular endothelial growth factor (P < 0.001). In co-stimulation assays of PM-exposed DC and alloreactive CD4+ T cells, both CEP and DEP directed a Th2-like pattern of cytokine production (e.g., enhanced IL-13 and IL-18 and suppressed IFN-γ production). CD4+ T cells were not functionally activated on exposure to either DEP or CEP. Car- and diesel-enriched particles exert a differential effect on DC activation. Our data support the hypothesis that DEP (and to a lesser extent CEP) regulate important functional aspects of human DC, supporting an adjuvant role for this material. PMID:17630318

  9. Dendritic Cell Lineage Potential in Human Early Hematopoietic Progenitors

    Directory of Open Access Journals (Sweden)

    Julie Helft

    2017-07-01

    Full Text Available Conventional dendritic cells (cDCs are thought to descend from a DC precursor downstream of the common myeloid progenitor (CMP. However, a mouse lymphoid-primed multipotent progenitor has been shown to generate cDCs following a DC-specific developmental pathway independent of monocyte and granulocyte poiesis. Similarly, here we show that, in humans, a large fraction of multipotent lymphoid early progenitors (MLPs gives rise to cDCs, in particular the subset known as cDC1, identified by co-expression of DNGR-1 (CLEC9A and CD141 (BDCA-3. Single-cell analysis indicates that over one-third of MLPs have the potential to efficiently generate cDCs. cDC1s generated from CMPs or MLPs do not exhibit differences in transcriptome or phenotype. These results demonstrate an early imprinting of the cDC lineage in human hematopoiesis and highlight the plasticity of developmental pathways giving rise to human DCs.

  10. Effect of aging and oral tolerance on dendritic cell function.

    Science.gov (United States)

    Simioni, P U; Fernandes, L G R; Gabriel, D L; Tamashiro, W M S C

    2010-01-01

    Oral tolerance can be induced in some mouse strains by gavage or spontaneous ingestion of dietary antigens. In the present study, we determined the influence of aging and oral tolerance on the secretion of co-stimulatory molecules by dendritic cells (DC), and on the ability of DC to induce proliferation and cytokine secretion by naive T cells from BALB/c and OVA transgenic (DO11.10) mice. We observed that oral tolerance could be induced in BALB/c mice (N = 5 in each group) of all ages (8, 20, 40, 60, and 80 weeks old), although a decline in specific antibody levels was observed in the sera of both tolerized and immunized mice with advancing age (40 to 80 weeks old). DC obtained from young, adult and middle-aged (8, 20, and 40 weeks old) tolerized mice were less efficient (65, 17 and 20%, respectively) than DC from immunized mice (P stimulating IFN-g, IL-4 and IL-10 production. However, TGF-beta levels were significantly elevated in co-cultures carried out with DC from tolerant mice (P production (P oral tolerance in BALB/c mice, but reduces DC functions, probably due to the decline of the expression of the CD86 surface marker.

  11. Dendritic cells regulate angiogenesis associated with liver fibrogenesis.

    Science.gov (United States)

    Blois, Sandra M; Piccioni, Flavia; Freitag, Nancy; Tirado-González, Irene; Moschansky, Petra; Lloyd, Rodrigo; Hensel-Wiegel, Karin; Rose, Matthias; Garcia, Mariana G; Alaniz, Laura D; Mazzolini, Guillermo

    2014-01-01

    During liver fibrogenesis the immune response and angiogenesis process are fine-tuned resulting in activation of hepatic stellate cells that produce an excess of extracellular matrix proteins. Dendritic cells (DC) play a central role modulating the liver immunity and have recently been implicated to favour fibrosis regression; although their ability to influence the development of fibrogenesis is unknown. Therefore, we explored whether the depletion of DC during early stages of liver injury has an impact in the development of fibrogenesis. Using the CD11c.DTR transgenic mice, DC were depleted in two experimental models of fibrosis in vivo. The effect of anti-angiogenic therapy was tested during early stages of liver fibrogenesis. DC depletion accelerates the development of fibrosis and as a consequence, the angiogenesis process is boosted. We observed up-regulation of pro-angiogenic factors together with an enhanced vascular endothelial growth factor (VEGF) bioavailability, mainly evidenced by the decrease of anti-angiogenic VEGF receptor 1 (also known as sFlt-1) levels. Interestingly, fibrogenesis process enhanced the expression of Flt-1 on hepatic DC and administration of sFlt-1 was sufficient to abrogate the acceleration of fibrogenesis upon DC depletion. Thus, DC emerge as novel players during the development of liver fibrosis regulating the angiogenesis process and thereby influencing fibrogenesis.

  12. Dendrite short-circuit and fuse effect on Li/polymer/Li cells

    International Nuclear Information System (INIS)

    Rosso, Michel; Brissot, Claire; Teyssot, Anna; Dolle, Mickael; Sannier, Lucas; Tarascon, Jean-Marie; Bouchet, Renaud; Lascaud, Stephane

    2006-01-01

    We report on experimental and theoretical studies of dendritic growth in Li/polymer/Li symmetric cells. Potential evolution with time, impedance and in situ microscopy experiments enable to characterise the onset and evolution of dendrites. In particular we observe that dendrites may burn when a high enough current goes through them, a thermo-fusible effect predicted in a previous paper and confirmed by SEM experiments. We present a calculation that gives a quantitative description of this effect: our results enable to understand a series of experimental data published in the literature concerning impedance variations observed while cycling lithium-polymer cells

  13. acquisition of antigens by airway dendritic cells. do we know enough?

    African Journals Online (AJOL)

    kiama

    These responses are thought to be mediated via dendritic cells, which are located in the basal ... delivery to the DC in the airways. Are the ... feature of inflammatory airway disease, like asthma .... drug delivery and as vectors in delivery of.

  14. Commitment to glycolysis sustains survival of NO-producing inflammatory dendritic cells

    NARCIS (Netherlands)

    Everts, Bart; Amiel, Eyal; van der Windt, Gerritje J. W.; Freitas, Tori C.; Chott, Robert; Yarasheski, Kevin E.; Pearce, Erika L.; Pearce, Edward J.

    2012-01-01

    TLR agonists initiate a rapid activation program in dendritic cells (DCs) that requires support from metabolic and bioenergetic resources. We found previously that TLR signaling promotes aerobic glycolysis and a decline in oxidative phosphorylation (OXHPOS) and that glucose restriction prevents

  15. 2-Azidoalkoxy-7-hydro-8-oxoadenine derivatives as TLR7 agonists inducing dendritic cell maturation.

    Science.gov (United States)

    Weterings, Jimmy J; Khan, Selina; van der Heden van Noort, Gerbrand J; Melief, Cornelis J M; Overkleeft, Herman S; van der Burg, Sjoerd H; Ossendorp, Ferry; van der Marel, Gijsbert A; Filippov, Dmitri V

    2009-04-15

    The synthesis of an array of 2-azidoalkoxy substituted 7-hydro-8-oxoadenines is described. The relation of the structure of these compounds and their ability to induce maturation of dendritic cells is evaluated.

  16. Primary Human Blood Dendritic Cells for Cancer Immunotherapy—Tailoring the Immune Response by Dendritic Cell Maturation

    Directory of Open Access Journals (Sweden)

    Simone P. Sittig

    2015-12-01

    Full Text Available Dendritic cell (DC-based cancer vaccines hold the great promise of tipping the balance from tolerance of the tumor to rejection. In the last two decades, we have gained tremendous knowledge about DC-based cancer vaccines. The maturation of DCs has proven indispensable to induce immunogenic T cell responses. We review the insights gained from the development of maturation cocktails in monocyte derived DC-based trials. More recently, we have also gained insights into the functional specialization of primary human blood DC subsets. In peripheral human blood, we can distinguish at least three primary DC subsets, namely CD1c+ and CD141+ myeloid DCs and plasmacytoid DCs. We reflect the current knowledge on maturation and T helper polarization by these blood DC subsets in the context of DC-based cancer vaccines. The maturation stimulus in combination with the DC subset will determine the type of T cell response that is induced. First trials with these natural DCs underline their excellent in vivo functioning and mark them as promising tools for future vaccination strategies.

  17. Adoptively transferred dendritic cells restore primary cell-mediated inflammatory competence to acutely malnourished weanling mice.

    Science.gov (United States)

    Hillyer, Lyn; Whitley, Charlene; Olver, Amy; Webster, Michelle; Steevels, Tessa; Woodward, Bill

    2008-02-01

    Immune depression associated with prepubescent malnutrition underlies a staggering burden of infection-related morbidity. This investigation centered on dendritic cells as potentially decisive in this phenomenon. C57BL/6J mice, initially 19 days old, had free access for 14 days to a complete diet or to a low-protein formulation that induced wasting deficits of protein and energy. Mice were sensitized by i.p. injection of sheep red blood cells on day 9, at which time one-half of the animals in each dietary group received a simultaneous injection of 10(6) syngeneic dendritic cells (JAWS II). All mice were challenged with the immunizing antigen in the right hind footpad on day 13, and the 24-hour delayed hypersensitivity response was assessed as percentage increase in footpad thickness. The low-protein diet reduced the inflammatory immune response, but JAWS cells, which exhibited immature phenotypic and functional characteristics, increased the response of both the malnourished group and the controls. By contrast, i.p. injection of 10(6) syngeneic T cells did not influence the inflammatory immune response of mice subjected to the low-protein protocol. Antigen-presenting cell numbers limited primary inflammatory cell-mediated competence in this model of wasting malnutrition, an outcome that challenges the prevailing multifactorial model of malnutrition-associated immune depression. Thus, a new dendritic cell-centered perspective emerges regarding the cellular mechanism underlying immune depression in acute pediatric protein and energy deficit.

  18. Conditional ablation of CD205+ conventional dendritic cells impacts the regulation of T-cell immunity and homeostasis in vivo.

    Science.gov (United States)

    Fukaya, Tomohiro; Murakami, Ryuichi; Takagi, Hideaki; Sato, Kaori; Sato, Yumiko; Otsuka, Haruna; Ohno, Michiko; Hijikata, Atsushi; Ohara, Osamu; Hikida, Masaki; Malissen, Bernard; Sato, Katsuaki

    2012-07-10

    Dendritic cells (DCs) are composed of multiple subsets that play a dual role in inducing immunity and tolerance. However, it is unclear how CD205(+) conventional DCs (cDCs) control immune responses in vivo. Here we generated knock-in mice with the selective conditional ablation of CD205(+) cDCs. CD205(+) cDCs contributed to antigen-specific priming of CD4(+) T cells under steady-state conditions, whereas they were dispensable for antigen-specific CD4(+) T-cell responses under inflammatory conditions. In contrast, CD205(+) cDCs were required for antigen-specific priming of CD8(+) T cells to generate cytotoxic T lymphocytes (CTLs) mediated through cross-presentation. Although CD205(+) cDCs were involved in the thymic generation of CD4(+) regulatory T cells (Tregs), they maintained the homeostasis of CD4(+) Tregs and CD4(+) effector T cells in peripheral and mucosal tissues. On the other hand, CD205(+) cDCs were involved in the inflammation triggered by Toll-like receptor ligand as well as bacterial and viral infections. Upon microbial infections, CD205(+) cDCs contributed to the cross-priming of CD8(+) T cells for generating antimicrobial CTLs to efficiently eliminate pathogens, whereas they suppressed antimicrobial CD4(+) T-cell responses. Thus, these findings reveal a critical role for CD205(+) cDCs in the regulation of T-cell immunity and homeostasis in vivo.

  19. Podoplanin (D2-40): A New Immunohistochemical Marker for Reactive Follicular Dendritic Cells and Follicular Dendritic Cell Sarcomas

    Science.gov (United States)

    Xie, Qingmei; Chen, Lugen; Fu, Kai; Harter, Josephine; Young, Ken H; Sunkara, Jaya; Novak, Deborah; Villanueva-Siles, Esperanza; Ratech, Howard

    2008-01-01

    The diagnosis of follicular dendritic cell (FDC) sarcoma can be challenging because of its morphologic overlaps with many other spindle cell neoplasms and, therefore, new phenotypic markers will be helpful in its differential diagnosis. Podoplanin is a mucin-type transmembrane glycoprotein that has recently been detected in reactive FDCs. In this study, we investigated the expression patterns of podoplanin using a new mouse monoclonal antibody D2-40, and compared them with CD21, a well-established FDC marker, in a comprehensive panel of cases. The panel included 4 FDC sarcomas, 38 spindle cell neoplasms of other types, 25 reactive lymphoid hyperplasia, and 117 lymphoid and 5 myeloid malignant hematopoietic neoplasms. Our study revealed that D2-40 strongly stained 3 of 4 FDC sarcomas. In contrast, D2-40 stained only 2/38 other spindle cell neoplasms tested. Furthermore, we observed that D2-40 highlighted more FDC meshworks than CD21 in Castleman's disease, follicular lymphoma, nodular lymphocyte predominance Hodgkin lymphoma, and residual reactive germinal centers in a variety of lymphoma types. D2-40 and CD21 stained an equal number of cases of reactive lymphoid hyperplasia, progressively transformed germinal centers and angioimmunoblastic T-cell lymphoma. No expression of podoplanin was detected in normal or neoplastic lymphoid and myeloid cells. We conclude that podoplanin (D2-40) is a sensitive and specific FDC marker, which is superior or equal to CD21 in evaluating both reactive and neoplastic FDCs. In addition, our results suggest that podoplanin (D2-40) can be used to support the diagnosis of FDC sarcoma. PMID:18784810

  20. Effect of aging and oral tolerance on dendritic cell function

    Directory of Open Access Journals (Sweden)

    P.U. Simioni

    2010-01-01

    Full Text Available Oral tolerance can be induced in some mouse strains by gavage or spontaneous ingestion of dietary antigens. In the present study, we determined the influence of aging and oral tolerance on the secretion of co-stimulatory molecules by dendritic cells (DC, and on the ability of DC to induce proliferation and cytokine secretion by naive T cells from BALB/c and OVA transgenic (DO11.10 mice. We observed that oral tolerance could be induced in BALB/c mice (N = 5 in each group of all ages (8, 20, 40, 60, and 80 weeks old, although a decline in specific antibody levels was observed in the sera of both tolerized and immunized mice with advancing age (40 to 80 weeks old. DC obtained from young, adult and middle-aged (8, 20, and 40 weeks old tolerized mice were less efficient (65, 17 and 20%, respectively than DC from immunized mice (P < 0.05 in inducing antigen-specific proliferation of naive T cells from both BALB/c and DO11.10 young mice, or in stimulating IFN-g, IL-4 and IL-10 production. However, TGF-β levels were significantly elevated in co-cultures carried out with DC from tolerant mice (P < 0.05. DC from both immunized and tolerized old and very old (60 and 80 weeks old mice were equally ineffective in inducing T cell proliferation and cytokine production (P < 0.05. A marked reduction in CD86+ marker expression was observed in DC isolated from both old and tolerized mice (75 and 50%, respectively. The results indicate that the aging process does not interfere with the establishment of oral tolerance in BALB/c mice, but reduces DC functions, probably due to the decline of the expression of the CD86 surface marker.

  1. Therapeutic Potential of Tolerogenic Dendritic Cells in IBD: From Animal Models to Clinical Application

    Directory of Open Access Journals (Sweden)

    Raquel Cabezón

    2013-01-01

    Full Text Available The gut mucosa undergoes continuous antigenic exposure from food antigens, commensal flora derived ligands, and pathogens. This constant stimulation results in controlled inflammatory responses that are effectively suppressed by multiple factors. This tight regulation, necessary to maintain intestinal homeostasis, is affected during inflammatory bowel diseases (IBD resulting in altered immune responses to harmless microorganisms. Dendritic cells (DCs are sentinels of immunity, located in peripheral and lymphoid tissues, which are essential for homeostasis of T cell-dependent immune responses. The expression of a particular set of pathogen recognition receptors allows DCs to initiate immune responses. However, in the absence of danger signals, different DC subsets can induce active tolerance by inducing regulatory T cells (Treg, inhibiting inflammatory T helper cell responses, or both. Interestingly, several protocols to generate clinical grade tolerogenic DC (tol-DCs in vitro have been described, opening the possibility to restore the intestinal homeostasis to bacterial flora by cellular therapy. In this review, we discuss different DC subsets and their role in IBD. Additionally, we will review preclinical studies performed in animal models while describing recent characterization of tol-DCs from Crohn’s disease patients for clinical application.

  2. Immune receptors involved in Streptococcus suis recognition by dendritic cells.

    Directory of Open Access Journals (Sweden)

    Marie-Pier Lecours

    Full Text Available Streptococcus suis is an important swine pathogen and an emerging zoonotic agent of septicemia and meningitis. Knowledge on host immune responses towards S. suis, and strategies used by this pathogen for subversion of these responses is scarce. The objective of this study was to identify the immune receptors involved in S. suis recognition by dendritic cells (DCs. Production of cytokines and expression of co-stimulatory molecules by DCs were shown to strongly rely on MyD88-dependent signaling pathways, suggesting that DCs recognize S. suis and become activated mostly through Toll-like receptor (TLR signaling. Supporting this fact, TLR2(-/- DCs were severely impaired in the release of several cytokines and the surface expression of CD86 and MHC-II. The release of IL-12p70 and CXC10, and the expression of CD40 were found to depend on signaling by both TLR2 and TLR9. The release of IL-23 and CXCL1 were partially dependent on NOD2. Finally, despite the fact that MyD88 signaling was crucial for DC activation and maturation, MyD88-dependent pathways were not implicated in S. suis internalization by DCs. This first study on receptors involved in DC activation by S. suis suggests a major involvement of MyD88 signaling pathways, mainly (but not exclusively through TLR2. A multimodal recognition involving a combination of different receptors seems essential for DC effective response to S. suis.

  3. The Influence of Ouabain on Human Dendritic Cells Maturation

    Directory of Open Access Journals (Sweden)

    C. R. Nascimento

    2014-01-01

    Full Text Available Although known as a Na,K-ATPase inhibitor, several other cellular and systemic actions have been ascribed to the steroid Ouabain (Oua. Particularly in the immune system, our group showed that Ouabain acts on decreasing lymphocyte proliferation, synergizing with glucocorticoids in spontaneous thymocyte apoptosis, and also lessening CD14 expression and blocking CD16 upregulation on human monocytes. However, Ouabain effects on dendritic cells (DCs were not explored so far. Considering the peculiar plasticity and the importance of DCs in immune responses, the aim of our study was to investigate DC maturation under Ouabain influence. To generate immature DCs, human monocytes were cultured with IL-4 and GM-CSF (5 days. To investigate Ouabain role on DC activation, DCs were stimulated with TNF-α for 48 h in the presence or absence of Ouabain. TNF-induced CD83 expression and IL-12 production were abolished in DCs incubated with 100 nM Ouabain, though DC functional capacity concerning lymphocyte activation remained unaltered. Nevertheless, TNF-α-induced antigen capture downregulation, another maturation marker, occurred even in the presence of Ouabain. Besides, Ouabain increased HLA-DR and CD86 expression, whereas CD80 expression was maintained. Collectively, our results suggest that DCs respond to Ouabain maturating into a distinct category, possibly contributing to the balance between immunity and tolerance.

  4. Dendritic Cells Promote Pancreatic Viability in Mice with Acute Pancreatitis

    Science.gov (United States)

    Bedrosian, Andrea S.; Nguyen, Andrew H.; Hackman, Michael; Connolly, Michael K.; Malhotra, Ashim; Ibrahim, Junaid; Cieza-Rubio, Napoleon E.; Henning, Justin R.; Barilla, Rocky; Rehman, Adeel; Pachter, H. Leon; Medina-Zea, Marco V.; Cohen, Steven M.; Frey, Alan B.; Acehan, Devrim; Miller, George

    2011-01-01

    Background & Aims Acute pancreatitis increases morbidity and mortality from organ necrosis by mechanisms that are incompletely understood. Dendritic cells (DCs) can promote or suppress inflammation, depending on their subtype and context. We investigated the roles of DC in development of acute pancreatitis. Methods Acute pancreatitis was induced in CD11c.DTR mice using caerulein or L-arginine; DCs were depleted by administration of diphtheria toxin. Survival was analyzed using Kaplan-Meier analysis. Results Numbers of MHC II+CD11c+DC increased 100-fold in pancreas of mice with acute pancreatitis, to account for nearly 15% of intra-pancreatic leukocytes. Intra-pancreatic DC acquired an immune phenotype in mice with acute pancreatitis; they expressed higher levels of MHC II and CD86 and increased production of interleukin-6, membrane cofactor protein (MCP)-1, and tumor necrosis factor (TNF)-α. However, rather than inducing an organ-destructive inflammatory process, DC were required for pancreatic viability; the exocrine pancreas died in mice that were depleted of DC and challenged with caerulein or L-arginine. All mice with pancreatitis that were depleted of DC died from acinar cell death within 4 days. Depletion of DC from mice with pancreatitis resulted in neutrophil infiltration and increased levels of systemic markers of inflammation. However, the organ necrosis associated with depletion of DC did not require infiltrating neutrophils, activation of NF-κB, or signaling by mitogen-activated protein kinase or TNF-α. Conclusions DC are required for pancreatic viability in mice with acute pancreatitis and might protect organs against cell stress. PMID:21801698

  5. Helicobacter pylori impairs murine dendritic cell responses to infection.

    Directory of Open Access Journals (Sweden)

    Ya-Hui Wang

    Full Text Available BACKGROUND: Helicobacter pylori, a human pathogen associated with chronic gastritis, peptic ulcer and gastric malignancies, is generally viewed as an extracellular microorganism. Here, we show that H. pylori replicates in murine bone marrow derived-dendritic cells (BMDCs within autophagosomes. METHODOLOGY/PRINCIPAL FINDINGS: A 10-fold increase of CFU is found between 2 h and 6 h p.i. in H. pylori-infected BMDCs. Autophagy is induced around the bacterium and participates at late time points of infection for the clearance of intracellular H. pylori. As a consequence of infection, LC3, LAMP1 and MHC class II molecules are retained within the H. pylori-containing vacuoles and export of MHC class II molecules to cell surface is blocked. However, formalin-fixed H. pylori still maintain this inhibitory activity in BMDC derived from wild type mice, but not in from either TLR4 or TLR2-deficient mice, suggesting the involvement of H. pylori-LPS in this process. TNF-alpha, IL-6 and IL-10 expression was also modulated upon infection showing a TLR2-specific dependent IL-10 secretion. No IL-12 was detected favoring the hypothesis of a down modulation of DC functions during H. pylori infection. Furthermore, antigen-specific T cells proliferation was also impaired upon infection. CONCLUSIONS/SIGNIFICANCE: H. pylori can infect and replicate in BMDCs and thereby affects DC-mediated immune responses. The implication of this new finding is discussed for the biological life cycle of H. pylori in the host.

  6. Denervation-induced homeostatic dendritic plasticity in morphological granule cell models

    Directory of Open Access Journals (Sweden)

    Hermann Cuntz

    2014-03-01

    Full Text Available Neuronal death and subsequent denervation of target areas are major consequences of several neurological conditions such asischemia or neurodegeneration (Alzheimer's disease. The denervation-induced axonal loss results in reorganization of the dendritic tree of denervated neurons. The dendritic reorganization has been previously studied using entorhinal cortex lesion (ECL. ECL leads to shortening and loss of dendritic segments in the denervated outer molecular layer of the dentate gyrus. However, the functional importance of these long-term dendritic alterations is not yet understood and their impact on neuronal electrical properties remains unclear. Here we analyzed what happens to the electrotonic structure and excitability of dentate granule cells after lesion-induced alterations of their dendritic morphology, assuming all other parameters remain equal. We performed comparative electrotonic analysis in anatomically and biophysically realistic compartmental models of 3D-reconstructed healthy and denervated granule cells. Using the method of morphological modeling based on optimization principles minimizing the amount of wiring and maximizing synaptic democracy, we built artificial granule cells which replicate morphological features of their real counterparts. Our results show that somatofugal and somatopetal voltage attenuation in the passive cable model are strongly reduced in denervated granule cells. In line with these predictions, the attenuation both of simulated backpropagating action potentials and forward propagating EPSPs was significantly reduced in dendrites of denervated neurons. Intriguingly, the enhancement of action potential backpropagation occurred specifically in the denervated dendritic layers. Furthermore, simulations of synaptic f-I curves revealed a homeostatic increase of excitability in denervated granule cells. In summary, our morphological and compartmental modeling indicates that unless modified by changes of

  7. Investigations of the functional states of dendritic cells under different conditioned microenvironments by Fourier transformed infrared spectroscopy.

    Science.gov (United States)

    Dong, Rong; Long, Jinhua; Xu, Xiaoli; Zhang, Chunlin; Wen, Zongyao; Li, Long; Yao, Weijuan; Zeng, Zhu

    2014-01-10

    Dendritic cells are potent and specialized antigen presenting cells, which play a crucial role in initiating and amplifying both the innate and adaptive immune responses. The dendritic cell-based vaccination against cancer has been clinically achieved promising successes. But there are still many challenges in its clinical application, especially for how to identify the functional states. The CD14+ monocytes were isolated from human peripheral blood after plastic adherence and purified to approximately 98% with cocktail immunomagnetic beads. The immature dendritic cells and mature dendritic cells were induced by traditional protocols. The resulting dendritic cells were cocultured with normal cells and cancer cells. The functional state of dendritic cells including immature dendritic cells (imDCs) and mature dendritic cells (mDCs) under different conditioned microenvironments were investigated by Fourier transformed infrared spectroscopy (FTIR) and molecular biological methods. The results of Fourier transformed infrared spectroscopy showed that the gene transcription activity and energy states of dendritic cells were specifically suppressed by tumor cells (P Fourier transformed infrared spectroscopy at given wave numbers were closely correlated with the expression levels of NF-κB (R2:0.69 and R2:0.81, respectively). Our results confirmed that the ratios of absorption intensities of Fourier transformed infrared spectroscopy at given wave numbers were positively correlated with the expression levels of NF-κB, suggesting that Fourier transformed infrared spectroscopy technology could be clinically applied to identify the functional states of dendritic cell when performing dendritic cell-based vaccination. It's significant for the simplification and standardization of dendritic cell-based vaccination clinical preparation protocols.

  8. Phenotype and Function of CD209+ Bovine Blood Dendritic Cells, Monocyte-Derived-Dendritic Cells and Monocyte-Derived Macrophages.

    Directory of Open Access Journals (Sweden)

    Kun Taek Park

    Full Text Available Phylogenic comparisons of the mononuclear phagocyte system (MPS of humans and mice demonstrate phenotypic divergence of dendritic cell (DC subsets that play similar roles in innate and adaptive immunity. Although differing in phenotype, DC can be classified into four groups according to ontogeny and function: conventional DC (cDC1 and cDC2, plasmacytoid DC (pDC, and monocyte derived DC (MoDC. DC of Artiodactyla (pigs and ruminants can also be sub-classified using this system, allowing direct functional and phenotypic comparison of MoDC and other DC subsets trafficking in blood (bDC. Because of the high volume of blood collections required to study DC, cattle offer the best opportunity to further our understanding of bDC and MoDC function in an outbred large animal species. As reported here, phenotyping DC using a monoclonal antibody (mAb to CD209 revealed CD209 is expressed on the major myeloid population of DC present in blood and MoDC, providing a phenotypic link between these two subsets. Additionally, the present study demonstrates that CD209 is also expressed on monocyte derived macrophages (MoΦ. Functional analysis revealed each of these populations can take up and process antigens (Ags, present them to CD4 and CD8 T cells, and elicit a T-cell recall response. Thus, bDC, MoDC, and MoΦ pulsed with pathogens or candidate vaccine antigens can be used to study factors that modulate DC-driven T-cell priming and differentiation ex vivo.

  9. The MEK1/2-ERK Pathway Inhibits Type I IFN Production in Plasmacytoid Dendritic Cells

    Directory of Open Access Journals (Sweden)

    Vaclav Janovec

    2018-02-01

    Full Text Available Recent studies have reported that the crosslinking of regulatory receptors (RRs, such as blood dendritic cell antigen 2 (BDCA-2 (CD303 or ILT7 (CD85g, of plasmacytoid dendritic cells (pDCs efficiently suppresses the production of type I interferons (IFN-I, α/β/ω and other cytokines in response to toll-like receptor 7 and 9 (TLR7/9 ligands. The exact mechanism of how this B cell receptor (BCR-like signaling blocks TLR7/9-mediated IFN-I production is unknown. Here, we stimulated BCR-like signaling by ligation of RRs with BDCA-2 and ILT7 mAbs, hepatitis C virus particles, or BST2 expressing cells. We compared BCR-like signaling in proliferating pDC cell line GEN2.2 and in primary pDCs from healthy donors, and addressed the question of whether pharmacological targeting of BCR-like signaling can antagonize RR-induced pDC inhibition. To this end, we tested the TLR9-mediated production of IFN-I and proinflammatory cytokines in pDCs exposed to a panel of inhibitors of signaling molecules involved in BCR-like, MAPK, NF-ĸB, and calcium signaling pathways. We found that MEK1/2 inhibitors, PD0325901 and U0126 potentiated TLR9-mediated production of IFN-I in GEN2.2 cells. More importantly, MEK1/2 inhibitors significantly increased the TLR9-mediated IFN-I production blocked in both GEN2.2 cells and primary pDCs upon stimulation of BCR-like or phorbol 12-myristate 13-acetate-induced protein kinase C (PKC signaling. Triggering of BCR-like and PKC signaling in pDCs resulted in an upregulation of the expression and phoshorylation of c-FOS, a downstream gene product of the MEK1/2-ERK pathway. We found that the total level of c-FOS was higher in proliferating GEN2.2 cells than in the resting primary pDCs. The PD0325901-facilitated restoration of the TLR9-mediated IFN-I production correlated with the abrogation of MEK1/2-ERK-c-FOS signaling. These results indicate that the MEK1/2-ERK pathway inhibits TLR9-mediated type I IFN production in pDCs and that

  10. Human antibodies to dendritic cells : generation, analysis and use in vaccination

    NARCIS (Netherlands)

    Lekkerkerker, A.N.

    2002-01-01

    Dendritic cells (DCs) are widely recognized as professional antigen presenting cells (APCs) that play a pivotal role in directing the immune response. DCs are a heterogeneous cell population that continuously derive from bone marrow cells and reside as sentinels in an immature stage in the

  11. Biodistribution of radiolabelled human dendritic cells injected by various routes

    International Nuclear Information System (INIS)

    Quillien, Veronique; Moisan, Annick; Carsin, Andre; Lesimple, Thierry; Lefeuvre, Claudia; Bertho, Nicolas; Devillers, Anne; Toujas, Louis; Adamski, Henri; Leberre, Claudine

    2005-01-01

    The purpose of this study was to investigate the biodistribution of mature dendritic cells (DCs) injected by various routes, during a cell therapy protocol. In the context of a vaccine therapy protocol for melanoma, DCs matured with Ribomunyl and interferon-gamma were labelled with 111 In-oxine and injected into eight patients along various routes: afferent lymphatic vessel (IL) (4 times), lymph node (IN) (5 times) and intradermally (ID) (6 times). Scintigraphic investigations showed that the IL route allowed localisation of 80% of injected radioactivity in eight to ten nodes. In three cases of IN injection, the entire radioactivity stagnated in the injected nodes, while in two cases, migration to adjacent nodes was observed. This migration was detected rapidly after injection, as with IL injections, suggesting that passive transport occurred along the physiological lymphatic pathways. In two of the six ID injections, 1-2% of injected radioactivity reached a proximal lymph node. Migration was detectable in the first hour, but increased considerably after 24 h, suggesting an active migration mechanism. In both of the aforementioned cases, DCs were strongly CCR7-positive, but this feature was not a sufficient condition for effective migration. In comparison with DCs matured with TNF-α, IL-1β, IL-6 and PGE2, our DCs showed a weaker in vitro migratory response to CCL21, despite comparable CCR7 expression, and higher allostimulatory and TH1 polarisation capacities. The IL route allowed reproducible administration of specified numbers of DCs. The IN route sometimes yielded fairly similar results, but not reproducibly. Lastly, we showed that DCs matured without PGE2 that have in vitro TH1 polarisation capacities can migrate to lymph nodes after ID injection. (orig.)

  12. Activation-induced cell death of dendritic cells is dependent on sphingosine kinase 1

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    Anja eSchwiebs

    2016-04-01

    Full Text Available Sphingosine 1-phosphate (S1P is an immune modulatory lipid mediator and has been implicated in numerous pathophysiological processes. S1P is produced by sphingosine kinase 1 (Sphk1 and Sphk2. Dendritic cells (DCs are central for the direction of immune responses and crucially involved in autoimmunity and cancerogenesis. In this study we examined the function and survival of bone marrow-derived DCs under long-term inflammatory stimulation. We observed that differentiated cells undergo activation-induced cell death upon LPS stimulation with an increased metabolic activity shortly after stimulation, followed by a rapid activation of caspase 3 and subsequent augmented apoptosis. Importantly, we highlight a profound role of Sphk1 in secretion of inflammatory cytokines and survival of dendritic cells that might be mediated by a change in sphingolipid levels as well as by a change in STAT3 expression. Cell growth during differentiation of Sphk1-deficient cells treated with the functional S1P receptor antagonist FTYP was reduced. Importantly, in dendritic cells we did not observe a compensatory regulation of Sphk2 mRNA in Sphk1-deficient cells. Instead, we discovered a massive increase in Sphk1 mRNA concentration upon long-term stimulation with LPS in wild type cells that might function as an attempt to rescue from inflammation-caused cell death. Taken together, in this investigation we describe details of a crucial involvement of sphingolipids and Sphk1 in activation-induced cell death during long-term immunogenic activity of DCs that might play an important role in autoimmunity and might explain the differences in immune response observed in in vivo studies of Sphk1 modulation.

  13. Cigarette Smoke Decreases the Maturation of Lung Myeloid Dendritic Cells.

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    Elena Arellano-Orden

    Full Text Available Conflicting data exist on the role of pulmonary dendritic cells (DCs and their maturation in patients with chronic obstructive pulmonary disease (COPD. Herein, we investigated whether disease severity and smoking status could affect the distribution and maturation of DCs in lung tissues of patients undergoing elective pneumectomy or lobectomy for suspected primary lung cancer.A total of 75 consecutive patients were included. Spirometry testing was used to identify COPD. Lung parenchyma sections anatomically distant from the primary lesion were examined. We used flow cytometry to identify different DCs subtypes-including BDCA1-positive myeloid DCs (mDCs, BDCA3-positive mDCs, and plasmacytoid DCs (pDCs-and determine their maturation markers (CD40, CD80, CD83, and CD86 in all participants. We also identified follicular DCs (fDCs, Langerhans DCs (LDCs, and pDCs in 42 patients by immunohistochemistry.COPD was diagnosed in 43 patients (16 current smokers and 27 former smokers, whereas the remaining 32 subjects were classified as non-COPD (11 current smokers, 13 former smokers, and 8 never smokers. The number and maturation of DCs did not differ significantly between COPD and non-COPD patients. However, the results of flow cytometry indicated that maturation markers CD40 and CD83 of BDCA1-positive mDCs were significantly decreased in smokers than in non-smokers (P = 0.023 and 0.013, respectively. Immunohistochemistry also revealed a lower number of LDCs in COPD patients than in non-COPD subjects.Cigarette smoke, rather than airflow limitation, is the main determinant of impaired DCs maturation in the lung.

  14. REGULATORY T CELLS AND VASECTOMY

    Science.gov (United States)

    Rival, Claudia; Wheeler, Karen; Jeffrey, Sarah; Qiao, Hui; Luu, Brian; Tewalt, Eric F; Engelhard, Victor H; Tardif, Stephen; Hardy, Daniel; del Rio, Roxana; Teuscher, Cory; Tung, Kenneth

    2013-01-01

    CD4+CD25+ regulatory T cells (Tregs) strongly influence the early and late autoimmune responses to meiotic germ cell antigens (MGCA) and the gonadal immunopathology in vasectomized mice. This is supported by the published and recently acquired information presented here. Within 24 hours of unilateral vasectomy (uni-vx) the ipsilateral epididymis undergoes epithelial cell apoptosis followed by necrosis, severe inflammation, and granuloma formation. Unexpectedly, vasectomy alone induced MGCA-specific tolerance. In contrast, uni-vx plus simultaneous Treg depletion resulted in MGCA-specific autoimmune response and bilateral autoimmune orchitis. Both tolerance and autoimmunity were strictly linked to the early epididymal injury. We now discovered that testicular autoimmunity in uni-vx mice did not occur when Treg depletion was delayed by one week. Remarkably, this delayed Treg depletion also prevented tolerance induction. Therefore, tolerance depends on a rapid de novo Treg response to MGCA exposed after vasectomy. Moreover, tolerance was blunted in mice genetically deficient in PD-1 ligand, suggesting the involvement of induced Treg. We conclude that pre-existing natural Treg prevents post-vasectomy autoimmunity, whereas vasectomy-induced Treg maintains post-vasectomy tolerance. We further discovered that vasectomized mice were still resistant to autoimmune orchitis induction for at least 12–16 months; thus, tolerance is long-lasting. Although significant sperm autoantibodies of low titers became detectable in uni-vx mice at seven months, the antibody titers fluctuated over time, suggesting a dynamic “balance” between the autoimmune and tolerance states. Finally, we observed severe epididymal fibrosis and hypo-spermatogenesis at 12 months after uni-vx: findings of highly critical clinical significance. PMID:24080233

  15. Immunotherapeutic efficacy of vaccines generated by fusion of dendritic cells and HPV16-associated tumour cells

    Czech Academy of Sciences Publication Activity Database

    Bubeník, Jan; Šímová, Jana; Bieblová, Jana; Reiniš, Milan; Indrová, Marie

    2005-01-01

    Roč. 16, Suppl. 1 (2005), s. 101 ISSN 1107-3756. [World Congress on Advances in Oncology /10./ and International Symposium on Molecular Medicine /8./. 05.10.13-05.10.15, Hersonissos] R&D Projects: GA ČR(CZ) GA301/04/0492; GA MZd(CZ) NR8004 Institutional research plan: CEZ:AV0Z50520514 Keywords : HPV16 * dendritic cells * vaccines Subject RIV: EC - Immunology

  16. Dynamic imaging of cell-free and cell-associated viral capture in mature dendritic cells.

    Science.gov (United States)

    Izquierdo-Useros, Nuria; Esteban, Olga; Rodriguez-Plata, Maria T; Erkizia, Itziar; Prado, Julia G; Blanco, Julià; García-Parajo, Maria F; Martinez-Picado, Javier

    2011-12-01

    Dendritic cells (DCs) capture human immunodeficiency virus (HIV) through a non-fusogenic mechanism that enables viral transmission to CD4(+) T cells, contributing to in vivo viral dissemination. Although previous studies have provided important clues to cell-free viral capture by mature DCs (mDCs), dynamic and kinetic insight on this process is still missing. Here, we used three-dimensional video microscopy and single-particle tracking approaches to dynamically dissect both cell-free and cell-associated viral capture by living mDCs. We show that cell-free virus capture by mDCs operates through three sequential phases: virus binding through specific determinants expressed in the viral particle, polarized or directional movements toward concrete regions of the cell membrane and virus accumulation in a sac-like structure where trapped viral particles display a hindered diffusive behavior. Moreover, real-time imaging of cell-associated viral transfer to mDCs showed a similar dynamics to that exhibited by cell-free virus endocytosis leading to viral accumulation in compartments. However, cell-associated HIV type 1 transfer to mDCs was the most effective pathway, boosted throughout enhanced cellular contacts with infected CD4(+) T cells. Our results suggest that in lymphoid tissues, mDC viral uptake could occur either by encountering cell-free or cell-associated virus produced by infected cells generating the perfect scenario to promote HIV pathogenesis and impact disease progression. © 2011 John Wiley & Sons A/S.

  17. Human monocytes undergo functional re-programming during differentiation to dendritic cell mediated by human extravillous trophoblasts.

    Science.gov (United States)

    Zhao, Lei; Shao, Qianqian; Zhang, Yun; Zhang, Lin; He, Ying; Wang, Lijie; Kong, Beihua; Qu, Xun

    2016-02-09

    Maternal immune adaptation is required for a successful pregnancy to avoid rejection of the fetal-placental unit. Dendritic cells within the decidual microenvironment lock in a tolerogenic profile. However, how these tolerogenic DCs are induced and the underlying mechanisms are largely unknown. In this study, we show that human extravillous trophoblasts redirect the monocyte-to-DC transition and induce regulatory dendritic cells. DCs differentiated from blood monocytes in the presence of human extravillous trophoblast cell line HTR-8/SVneo displayed a DC-SIGN(+)CD14(+)CD1a(-) phenotype, similar with decidual DCs. HTR8-conditioned DCs were unable to develop a fully mature phenotype in response to LPS, and altered the cytokine secretory profile significantly. Functionally, conditioned DCs poorly induced the proliferation and activation of allogeneic T cells, whereas promoted CD4(+)CD25(+)Foxp3(+) Treg cells generation. Furthermore, the supernatant from DC and HTR-8/SVneo coculture system contained significant high amount of M-CSF and MCP-1. Using neutralizing antibodies, we discussed the role of M-CSF and MCP-1 during monocyte-to-DCs differentiation mediated by extravillous trophoblasts. Our data indicate that human extravillous trophoblasts play an important role in modulating the monocyte-to-DC differentiation through M-CSF and MCP-1, which facilitate the establishment of a tolerogenic microenvironment at the maternal-fetal interface.

  18. Role of Natural Killer and Dendritic Cell Crosstalk in Immunomodulation by Commensal Bacteria Probiotics

    DEFF Research Database (Denmark)

    Rizzello, Valeria; Bonaccorsi, Irene; Dongarra, Maria Luisa

    2011-01-01

    A cooperative dialogue between natural killer (NK) cells and dendritic cells (DCs) has been elucidated in the last years. They help each other to acquire their complete functions, both in the periphery and in the secondary lymphoid organs. Thus, NK cells' activation by dendritic cells allows the ......-dependent immunomodulatory effects. We particularly aim to highlight the ability of distinct species of commensal bacterial probiotics to differently affect the outcome of DC/NK cross-talk and consequently to differently influence the polarization of the adaptive immune response....

  19. TGFβR signalling controls CD103+CD11b+ dendritic cell development in the intestine

    NARCIS (Netherlands)

    L.J. Bain (Lisa); Montgomery, J. (J.); C.L. Scott (C.); J.M. Kel (Junda); M.J.H. Girard-Madoux (Mathilde); L. Martens (Liesbet); Zangerle-Murray, T.F.P. (T. F.P.); J.L. Ober-Blöbaum (Julia); D.J. Lindenbergh-Kortleve (Dicky); J.N. Samsom (Janneke); S. Henri (Sandrine); T. Lawrence (Toby); Y. Saeys (Yvan); B. Malissen (Bernard); M. Dalod (Marc); B.E. Clausen (Bjorn); Mowat, A.M. (A. McI.)

    2017-01-01

    textabstractCD103+CD11b+ dendritic cells (DCs) are unique to the intestine, but the factors governing their differentiation are unclear. Here we show that transforming growth factor receptor 1 (TGFβR1) has an indispensable, cell intrinsic role in the development of these cells. Deletion of Tgfbr1

  20. Collagen I-induced dendritic cells activation is regulated by TNF-α ...

    Indian Academy of Sciences (India)

    2015-02-04

    Feb 4, 2015 ... tion factor IRF4, when compared to collagen I only treated cells. Collectively, our ... and multiple scelerosis, use of TNF-α inhibitors is an important treatment ..... sclerosis complex 1 in dendritic cell activation of CD4 T cells by.

  1. Molecular characterization of dendritic cells operating at the interface of innate or acquired immunity.

    NARCIS (Netherlands)

    Figdor, C.G.

    2003-01-01

    Dendritic Cells (DC) are natural adjuvants able to elicit specific cellular interactions and priming of naive T cells at a mature stage of their differentiation. Recent genomic approaches helped defining DC or Langherans Cells (LC) in more molecular terms. DC-SIGN, the DC specific ICAM-3 grabbing

  2. Cdc42-dependent actin dynamics controls maturation and secretory activity of dendritic cells

    DEFF Research Database (Denmark)

    Schulz, Anna M; Stutte, Susanne; Hogl, Sebastian

    2015-01-01

    Cell division cycle 42 (Cdc42) is a member of the Rho guanosine triphosphatase family and has pivotal functions in actin organization, cell migration, and proliferation. To further study the molecular mechanisms of dendritic cell (DC) regulation by Cdc42, we used Cdc42-deficient DCs. Cdc42 defici...

  3. Geranylgeranyltransferase I is essential for dendritic development of cerebellar Purkinje cells

    Directory of Open Access Journals (Sweden)

    Wu Kong-Yan

    2010-06-01

    Full Text Available Abstract Background During cerebellar development, Purkinje cells (PCs form the most elaborate dendritic trees among neurons in the brain, but the mechanism regulating PC arborization remains largely unknown. Geranylgeranyltransferase I (GGT is a prenyltransferase that is responsible for lipid modification of several signaling proteins, such as Rho family small GTPase Rac1, which has been shown to be involved in neuronal morphogenesis. Here we show that GGT plays an important role in dendritic development of PCs. Results We found that GGT was abundantly expressed in the developing rat cerebellum, in particular molecular layer (ML, the region enriched with PC dendrites. Inhibition or down-regulation of GGT using small interference RNA (siRNA inhibited dendritic development of PCs. In contrast, up-regulation of GGT promoted dendritic arborization of PCs. Furthermore, neuronal depolarization induced by high K+ or treatment with brain-derived neurotrophic factor (BDNF promoted membrane association of Rac1 and dendritic development of PCs in cultured cerebellar slices. The effect of BDNF or high K+ was inhibited by inhibition or down-regulation of GGT. Conclusion Our results indicate that GGT plays an important role in Purkinje cell development, and suggest a novel role of GGT in neuronal morphogenesis in vivo.

  4. The scavenger receptor MARCO modulates TLR-induced responses in dendritic cells.

    Directory of Open Access Journals (Sweden)

    Haydn T Kissick

    Full Text Available The scavenger receptor MARCO mediates macrophage recognition and clearance of pathogens and their polyanionic ligands. However, recent studies demonstrate MARCO expression and function in dendritic cells, suggesting MARCO might serve to bridge innate and adaptive immunity. To gain additional insight into the role of MARCO in dendritic cell activation and function, we profiled transcriptomes of mouse splenic dendritic cells obtained from MARCO deficient mice and their wild type counterparts under resting and activating conditions. In silico analysis uncovered major alterations in gene expression in MARCO deficient dendritic cells resulting in dramatic alterations in key dendritic cell-specific pathways and functions. Specifically, changes in CD209, FCGR4 and Complement factors can have major consequences on DC-mediated innate responses. Notably, these perturbations were magnified following activation with the TLR-4 agonist lipopolysaccharide. To validate our in silico data, we challenged DC's with various agonists that recognize all mouse TLRs and assessed expression of a set of immune and inflammatory marker genes. This approach identified a differential contribution of MARCO to TLR activation and validated a major role for MARCO in mounting an inflammatory response. Together, our data demonstrate that MARCO differentially affects TLR-induced DC activation and suggest targeting of MARCO could lead to different outcomes that depend on the inflammatory context encountered by DC.

  5. Clinical Tolerogenic Dendritic Cells: Exploring Therapeutic Impact on Human Autoimmune Disease

    Directory of Open Access Journals (Sweden)

    Brett Eugene Phillips

    2017-10-01

    Full Text Available Tolerogenic dendritic cell (tDC-based clinical trials for the treatment of autoimmune diseases are now a reality. Clinical trials are currently exploring the effectiveness of tDC to treat autoimmune diseases of type 1 diabetes mellitus, rheumatoid arthritis, multiple sclerosis (MS, and Crohn’s disease. This review will address tDC employed in current clinical trials, focusing on cell characteristics, mechanisms of action, and clinical findings. To date, the publicly reported human trials using tDC indicate that regulatory lymphocytes (largely Foxp3+ T-regulatory cell and, in one trial, B-regulatory cells are, for the most part, increased in frequency in the circulation. Other than this observation, there are significant differences in the major phenotypes of the tDC. These differences may affect the outcome in efficacy of recently launched and impending phase II trials. Recent efforts to establish a catalog listing where tDC converge and diverge in phenotype and functional outcome are an important first step toward understanding core mechanisms of action and critical “musts” for tDC to be therapeutically successful. In our view, the most critical parameter to efficacy is in vivo stability of the tolerogenic activity over phenotype. As such, methods that generate tDC that can induce and stably maintain immune hyporesponsiveness to allo- or disease-specific autoantigens in the presence of powerful pro-inflammatory signals are those that will fare better in primary endpoints in phase II clinical trials (e.g., disease improvement, preservation of autoimmunity-targeted tissue, allograft survival. We propose that pre-treatment phenotypes of tDC in the absence of functional stability are of secondary value especially as such phenotypes can dramatically change following administration, especially under dynamic changes in the inflammatory state of the patient. Furthermore, understanding the outcomes of different methods of cell delivery and sites

  6. 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.

  7. Invasion of Dendritic Cells, Macrophages and Neutrophils by the Bordetella Adenylate Cyclase Toxin: A Subversive Move to Fool Host Immunity.

    Science.gov (United States)

    Fedele, Giorgio; Schiavoni, Ilaria; Adkins, Irena; Klimova, Nela; Sebo, Peter

    2017-09-21

    Adenylate cyclase toxin (CyaA) is released in the course of B. pertussis infection in the host's respiratory tract in order to suppress its early innate and subsequent adaptive immune defense. CD11b-expressing dendritic cells (DC), macrophages and neutrophils are professional phagocytes and key players of the innate immune system that provide a first line of defense against invading pathogens. Recent findings revealed the capacity of B. pertussis CyaA to intoxicate DC with high concentrations of 3',5'-cyclic adenosine monophosphate (cAMP), which ultimately skews the host immune response towards the expansion of Th17 cells and regulatory T cells. CyaA-induced cAMP signaling swiftly incapacitates opsonophagocytosis, oxidative burst and NO-mediated killing of bacteria by neutrophils and macrophages. The subversion of host immune responses by CyaA after delivery into DC, macrophages and neutrophils is the subject of this review.

  8. Invasion of Dendritic Cells, Macrophages and Neutrophils by the Bordetella Adenylate Cyclase Toxin: A Subversive Move to Fool Host Immunity

    Directory of Open Access Journals (Sweden)

    Giorgio Fedele

    2017-09-01

    Full Text Available Adenylate cyclase toxin (CyaA is released in the course of B. pertussis infection in the host’s respiratory tract in order to suppress its early innate and subsequent adaptive immune defense. CD11b-expressing dendritic cells (DC, macrophages and neutrophils are professional phagocytes and key players of the innate immune system that provide a first line of defense against invading pathogens. Recent findings revealed the capacity of B. pertussis CyaA to intoxicate DC with high concentrations of 3′,5′-cyclic adenosine monophosphate (cAMP, which ultimately skews the host immune response towards the expansion of Th17 cells and regulatory T cells. CyaA-induced cAMP signaling swiftly incapacitates opsonophagocytosis, oxidative burst and NO-mediated killing of bacteria by neutrophils and macrophages. The subversion of host immune responses by CyaA after delivery into DC, macrophages and neutrophils is the subject of this review.

  9. Th17 Cells and Activated Dendritic Cells Are Increased in Vitiligo Lesions

    Science.gov (United States)

    Fuentes-Duculan, Judilyn; Moussai, Dariush; Gulati, Nicholas; Sullivan-Whalen, Mary; Gilleaudeau, Patricia; Cohen, Jules A.; Krueger, James G.

    2011-01-01

    Background Vitiligo is a common skin disorder, characterized by progressive skin de-pigmentation due to the loss of cutaneous melanocytes. The exact cause of melanocyte loss remains unclear, but a large number of observations have pointed to the important role of cellular immunity in vitiligo pathogenesis. Methodology/Principal Findings In this study, we characterized T cell and inflammation-related dermal dendritic cell (DC) subsets in pigmented non-lesional, leading edge and depigmented lesional vitiligo skin. By immunohistochemistry staining, we observed enhanced populations of CD11c+ myeloid dermal DCs and CD207+ Langerhans cells in leading edge vitiligo biopsies. DC-LAMP+ and CD1c+ sub-populations of dermal DCs expanded significantly in leading edge and lesional vitiligo skin. We also detected elevated tissue mRNA levels of IL-17A in leading edge skin biopsies of vitiligo patients, as well as IL-17A positive T cells by immunohistochemistry and immunofluorescence. Langerhans cells with activated inflammasomes were also noted in lesional vitiligo skin, along with increased IL-1ß mRNA, which suggest the potential of Langerhans cells to drive Th17 activation in vitiligo. Conclusions/Significance These studies provided direct tissue evidence that implicates active Th17 cells in vitiligo skin lesions. We characterized new cellular immune elements, in the active margins of vitiligo lesions (e.g. populations of epidermal and dermal dendritic cells subsets), which could potentially drive the inflammatory responses. PMID:21541348

  10. TLR7/TLR8 Activation Restores Defective Cytokine Secretion by Myeloid Dendritic Cells but Not by Plasmacytoid Dendritic Cells in HIV-Infected Pregnant Women and Newborns.

    Directory of Open Access Journals (Sweden)

    Elaine Cristina Cardoso

    Full Text Available Mother-to-child transmission (MTCT of HIV-1 has been significantly reduced with the use of antiretroviral therapies, resulting in an increased number of HIV-exposed uninfected infants. The consequences of HIV infection on the innate immune system of both mother-newborn are not well understood. In this study, we analyzed peripheral blood and umbilical cord blood (CB collected from HIV-1-infected and uninfected pregnant women. We measured TNF-α, IL-10 and IFN-α secretion after the stimulation of the cells with agonists of both extracellular Toll-like receptors (TLRs (TLR2, TLR4 and TLR5 and intracellular TLRs (TLR7, TLR7/8 and TLR9. Moreover, as an indicator of the innate immune response, we evaluated the responsiveness of myeloid dendritic cells (mDCs and plasmacytoid DCs (pDCs to TLRs that are associated with the antiviral response. Our results showed that peripheral blood mononuclear cells (PBMCs from HIV-1-infected mothers and CB were defective in TNF-α production after activation by TLR2, TLR5, TLR3 and TLR7. However, the TNF-α response was preserved after TLR7/8 (CL097 stimulation, mainly in the neonatal cells. Furthermore, only CL097 activation was able to induce IL-10 and IFN-α secretion in both maternal and CB cells in the infected group. An increase in IFN-α secretion was observed in CL097-treated CB from HIV-infected mothers compared with control mothers. The effectiveness of CL097 stimulation was confirmed by observation of similar mRNA levels of interferon regulatory factor-7 (IRF-7, IFN-α and TNF-α in PBMCs of both groups. The function of both mDCs and pDCs was markedly compromised in the HIV-infected group, and although TLR7/TLR8 activation overcame the impairment in TNF-α secretion by mDCs, such stimulation was unable to reverse the dysfunctional type I IFN response by pDCs in the HIV-infected samples. Our findings highlight the dysfunction of innate immunity in HIV-infected mother-newborn pairs. The activation of the TLR7

  11. TLR7/TLR8 Activation Restores Defective Cytokine Secretion by Myeloid Dendritic Cells but Not by Plasmacytoid Dendritic Cells in HIV-Infected Pregnant Women and Newborns.

    Science.gov (United States)

    Cardoso, Elaine Cristina; Pereira, Nátalli Zanete; Mitsunari, Gabrielle Eimi; Oliveira, Luanda Mara da Silva; Ruocco, Rosa Maria S A; Francisco, Rossana Pulcineli Vieira; Zugaib, Marcelo; da Silva Duarte, Alberto José; Sato, Maria Notomi

    2013-01-01

    Mother-to-child transmission (MTCT) of HIV-1 has been significantly reduced with the use of antiretroviral therapies, resulting in an increased number of HIV-exposed uninfected infants. The consequences of HIV infection on the innate immune system of both mother-newborn are not well understood. In this study, we analyzed peripheral blood and umbilical cord blood (CB) collected from HIV-1-infected and uninfected pregnant women. We measured TNF-α, IL-10 and IFN-α secretion after the stimulation of the cells with agonists of both extracellular Toll-like receptors (TLRs) (TLR2, TLR4 and TLR5) and intracellular TLRs (TLR7, TLR7/8 and TLR9). Moreover, as an indicator of the innate immune response, we evaluated the responsiveness of myeloid dendritic cells (mDCs) and plasmacytoid DCs (pDCs) to TLRs that are associated with the antiviral response. Our results showed that peripheral blood mononuclear cells (PBMCs) from HIV-1-infected mothers and CB were defective in TNF-α production after activation by TLR2, TLR5, TLR3 and TLR7. However, the TNF-α response was preserved after TLR7/8 (CL097) stimulation, mainly in the neonatal cells. Furthermore, only CL097 activation was able to induce IL-10 and IFN-α secretion in both maternal and CB cells in the infected group. An increase in IFN-α secretion was observed in CL097-treated CB from HIV-infected mothers compared with control mothers. The effectiveness of CL097 stimulation was confirmed by observation of similar mRNA levels of interferon regulatory factor-7 (IRF-7), IFN-α and TNF-α in PBMCs of both groups. The function of both mDCs and pDCs was markedly compromised in the HIV-infected group, and although TLR7/TLR8 activation overcame the impairment in TNF-α secretion by mDCs, such stimulation was unable to reverse the dysfunctional type I IFN response by pDCs in the HIV-infected samples. Our findings highlight the dysfunction of innate immunity in HIV-infected mother-newborn pairs. The activation of the TLR7/8 pathway

  12. Phospholipid Homeostasis Regulates Dendrite Morphogenesis in Drosophila Sensory Neurons

    Directory of Open Access Journals (Sweden)

    Shan Meltzer

    2017-10-01

    Full Text Available Disruptions in lipid homeostasis have been observed in many neurodevelopmental disorders that are associated with dendrite morphogenesis defects. However, the molecular mechanisms of how lipid homeostasis affects dendrite morphogenesis are unclear. We find that easily shocked (eas, which encodes a kinase with a critical role in phospholipid phosphatidylethanolamine (PE synthesis, and two other enzymes in this synthesis pathway are required cell autonomously in sensory neurons for dendrite growth and stability. Furthermore, we show that the level of Sterol Regulatory Element-Binding Protein (SREBP activity is important for dendrite development. SREBP activity increases in eas mutants, and decreasing the level of SREBP and its transcriptional targets in eas mutants largely suppresses the dendrite growth defects. Furthermore, reducing Ca2+ influx in neurons of eas mutants ameliorates the dendrite morphogenesis defects. Our study uncovers a role for EAS kinase and reveals the in vivo function of phospholipid homeostasis in dendrite morphogenesis.

  13. The microRNA bantam regulates a developmental transition in epithelial cells that restricts sensory dendrite growth

    OpenAIRE

    Jiang, Nan; Soba, Peter; Parker, Edward; Kim, Charles C.; Parrish, Jay Z.

    2014-01-01

    As animals grow, many early born structures grow by cell expansion rather than cell addition; thus growth of distinct structures must be coordinated to maintain proportionality. This phenomenon is particularly widespread in the nervous system, with dendrite arbors of many neurons expanding in concert with their substrate to sustain connectivity and maintain receptive field coverage as animals grow. After rapidly growing to establish body wall coverage, dendrites of Drosophila class IV dendrit...

  14. Active Dendrites and Differential Distribution of Calcium Channels Enable Functional Compartmentalization of Golgi Cells.

    Science.gov (United States)

    Rudolph, Stephanie; Hull, Court; Regehr, Wade G

    2015-11-25

    Interneurons are essential to controlling excitability, timing, and synaptic integration in neuronal networks. Golgi cells (GoCs) serve these roles at the input layer of the cerebellar cortex by releasing GABA to inhibit granule cells (grcs). GoCs are excited by mossy fibers (MFs) and grcs and provide feedforward and feedback inhibition to grcs. Here we investigate two important aspects of GoC physiology: the properties of GoC dendrites and the role of calcium signaling in regulating GoC spontaneous activity. Although GoC dendrites are extensive, previous studies concluded they are devoid of voltage-gated ion channels. Hence, the current view holds that somatic voltage signals decay passively within GoC dendrites, and grc synapses onto distal dendrites are not amplified and are therefore ineffective at firing GoCs because of strong passive attenuation. Using whole-cell recording and calcium imaging in rat slices, we find that dendritic voltage-gated sodium channels allow somatic action potentials to activate voltage-gated calcium channels (VGCCs) along the entire dendritic length, with R-type and T-type VGCCs preferentially located distally. We show that R- and T-type VGCCs located in the dendrites can boost distal synaptic inputs and promote burst firing. Active dendrites are thus critical to the regulation of GoC activity, and consequently, to the processing of input to the cerebellar cortex. In contrast, we find that N-type channels are preferentially located near the soma, and control the frequency and pattern of spontaneous firing through their close association with calcium-activated potassium (KCa) channels. Thus, VGCC types are differentially distributed and serve specialized functions within GoCs. Interneurons are essential to neural processing because they modulate excitability, timing, and synaptic integration within circuits. At the input layer of the cerebellar cortex, a single type of interneuron, the Golgi cell (GoC), carries these functions. The

  15. Induction of Regulatory T Cells by Intravenous Immunoglobulin: A Bridge between Adaptive and Innate Immunity.

    Science.gov (United States)

    Kaufman, Gabriel N; Massoud, Amir H; Dembele, Marieme; Yona, Madelaine; Piccirillo, Ciriaco A; Mazer, Bruce D

    2015-01-01

    Intravenous immunoglobulin (IVIg) is a polyclonal immunoglobulin G preparation with potent immunomodulatory properties. The mode of action of IVIg has been investigated in multiple disease states, with various mechanisms described to account for its benefits. Recent data indicate that IVIg increases both the number and the suppressive capacity of regulatory T cells, a subpopulation of T cells that are essential for immune homeostasis. IVIg alters dendritic cell function, cytokine and chemokine networks, and T lymphocytes, leading to development of regulatory T cells. The ability of IVIg to influence Treg induction has been shown both in animal models and in human diseases. In this review, we discuss data on the potential mechanisms contributing to the interaction between IVIg and the regulatory T-cell compartment.

  16. IRF8 dependent classical dendritic cells are essential for intestinal T cell homeostasis

    DEFF Research Database (Denmark)

    Luda, K.; Joeris, Thorsten; Persson, E. K.

    2016-01-01

    The role of dendritic cells (DCs) in intestinal immune homeostasis remains incompletely defined. Here we show that mice lacking IRF8 dependent DCs have reduced numbers of T cells in the small intestine (SI), but not large intestine (LI), including an almost complete absence of SI CD8ab+ andCD4+CD8......aa+ T cells; the latter requiring b8 integrin expression by migratory IRF8 dependent CD103+CD11b- DCs. SI homing receptor induction was impaired during T cell priming in mesenteric lymph nodes (MLN), which correlated with a reduction in aldehyde dehydrogenase activity by SI derived MLN DCs......, and inefficient T cell localization to the SI. Finally, mice with a DC deletion in IRF8 lacked intestinal T helper 1 (Th1) cells, and failed to support Th1 cell differentiation in MLN and mount Th1 responses to Trichuris muris infection. Collectively these results highlight multiple non-redundant roles for IRF8...

  17. The modular nature of dendritic cell responses to commensal and pathogenic fungi.

    Directory of Open Access Journals (Sweden)

    Lisa Rizzetto

    Full Text Available The type of adaptive immune response following host-fungi interaction is largely determined at the level of the antigen-presenting cells, and in particular by dendritic cells (DCs. The extent to which transcriptional regulatory events determine the decision making process in DCs is still an open question. By applying the highly structured DC-ATLAS pathways to analyze DC responses, we classified the various stimuli by revealing the modular nature of the different transcriptional programs governing the recognition of either pathogenic or commensal fungi. Through comparison of the network parts affected by DC stimulation with fungal cells and purified single agonists, we could determine the contribution of each receptor during the recognition process. We observed that initial recognition of a fungus creates a temporal window during which the simultaneous recruitment of cell surface receptors can intensify, complement and sustain the DC activation process. The breakdown of the response to whole live cells, through the purified components, showed how the response to invading fungi uses a set of specific modules. We find that at the start of fungal recognition, DCs rapidly initiate the activation process. Ligand recognition is further enhanced by over-expression of the receptor genes, with a significant correspondence between gene expression and protein levels and function. Then a marked decrease in the receptor levels follows, suggesting that at this moment the DC commits to a specific fate. Overall our pathway based studies show that the temporal window of the fungal recognition process depends on the availability of ligands and is different for pathogens and commensals. Modular analysis of receptor and signalling-adaptor expression changes, in the early phase of pathogen recognition, is a valuable tool for rapid and efficient dissection of the pathogen derived components that determine the phenotype of the DC and thereby the type of immune response

  18. Tolerogenic Dendritic Cells in Solid Organ Transplantation: Where Do We Stand?

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    Eros Marín

    2018-02-01

    Full Text Available Over the past century, solid organ transplantation has been improved both at a surgical and postoperative level. However, despite the improvement in efficiency, safety, and survival, we are still far from obtaining full acceptance of all kinds of allograft in the absence of concomitant treatments. Today, transplanted patients are treated with immunosuppressive drugs (IS to minimize immunological response in order to prevent graft rejection. Nevertheless, the lack of specificity of IS leads to an increase in the risk of cancer and infections. At this point, cell therapies have been shown as a novel promising resource to minimize the use of IS in transplantation. The main strength of cell therapy is the opportunity to generate allograft-specific tolerance, promoting in this way long-term allograft survival. Among several other regulatory cell types, tolerogenic monocyte-derived dendritic cells (Tol-MoDCs appear to be an interesting candidate for cell therapy due to their ability to perform specific antigen presentation and to polarize immune response to immunotolerance. In this review, we describe the characteristics and the mechanisms of action of both human Tol-MoDCs and rodent tolerogenic bone marrow-derived DCs (Tol-BMDCs. Furthermore, studies performed in transplantation models in rodents and non-human primates corroborate the potential of Tol-BMDCs for immunoregulation. In consequence, Tol-MoDCs have been recently evaluated in sundry clinical trials in autoimmune diseases and shown to be safe. In addition to autoimmune diseases clinical trials, Tol-MoDC is currently used in the first phase I/II clinical trials in transplantation. Translation of Tol-MoDCs to clinical application in transplantation will also be discussed in this review.

  19. Human cytomegalovirus alters localization of MHC class II and dendrite morphology in mature Langerhans cells.

    Science.gov (United States)

    Lee, Andrew W; Hertel, Laura; Louie, Ryan K; Burster, Timo; Lacaille, Vashti; Pashine, Achal; Abate, Davide A; Mocarski, Edward S; Mellins, Elizabeth D

    2006-09-15

    Hemopoietic stem cell-derived mature Langerhans-type dendritic cells (LC) are susceptible to productive infection by human CMV (HCMV). To investigate the impact of infection on this cell type, we examined HLA-DR biosynthesis and trafficking in mature LC cultures exposed to HCMV. We found decreased surface HLA-DR levels in viral Ag-positive as well as in Ag-negative mature LC. Inhibition of HLA-DR was independent of expression of unique short US2-US11 region gene products by HCMV. Indeed, exposure to UV-inactivated virus, but not to conditioned medium from infected cells, was sufficient to reduce HLA-DR on mature LC, implicating particle binding/penetration in this effect. Reduced surface levels reflected an altered distribution of HLA-DR because total cellular HLA-DR was not diminished. Accumulation of HLA-DR was not explained by altered cathepsin S activity. Mature, peptide-loaded HLA-DR molecules were retained within cells, as assessed by the proportion of SDS-stable HLA-DR dimers. A block in egress was implicated, as endocytosis of surface HLA-DR was not increased. Immunofluorescence microscopy corroborated the intracellular retention of HLA-DR and revealed markedly fewer HLA-DR-positive dendritic projections in infected mature LC. Unexpectedly, light microscopic analyses showed a dramatic loss of the dendrites themselves and immunofluorescence revealed that cytoskeletal elements crucial for the formation and maintenance of dendrites are disrupted in viral Ag-positive cells. Consistent with these dendrite effects, HCMV-infected mature LC exhibit markedly reduced chemotaxis in response to lymphoid chemokines. Thus, HCMV impedes MHC class II molecule trafficking, dendritic projections, and migration of mature LC. These changes likely contribute to the reduced activation of CD4+ T cells by HCMV-infected mature LC.

  20. Orf virus IL-10 reduces monocyte, dendritic cell and mast cell recruitment to inflamed skin.

    Science.gov (United States)

    Bennett, Jared R; Lateef, Zabeen; Fleming, Stephen B; Mercer, Andrew A; Wise, Lyn M

    2016-02-02

    Orf virus (ORFV) is a zoonotic parapoxvirus that causes pustular dermatitis of sheep, and occasionally humans. Despite causing sustained infections, ORFV induces only a transient increase in pro-inflammatory signalling and the trafficking of innate immune cells within the skin seems to be impaired. An explanation for this tempered response to ORFV infection may lie in its expression of a homolog of the anti-inflammatory cytokine, interleukin (IL)-10. Using a murine model in which inflammation was induced by bacterial lipopolysaccharide, we examined the effects of the ORFV-IL-10 protein on immune cell trafficking to and from the skin. ORFV-IL-10 limited the recruitment of blood-derived Gr-1(int)/CD11b(int) monocytes, CD11c(+ve)/MHC-II(+ve) dendritic cells and c-kit(+ve)/FcεR1(+ve) mature mast cells into inflamed skin. ORFV-IL-10 also suppressed the activation of CD11c(+ve)/MHC-II(+ve) dendritic cells within the skin, reducing their trafficking to the draining lymph node. These findings suggest that expression of IL-10 by ORFV may contribute to the impaired trafficking of innate immune cells within infected skin. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Oxidized low-density lipoprotein-induced apoptotic dendritic cells as a novel therapy for atherosclerosis

    NARCIS (Netherlands)

    Frodermann, Vanessa; van Puijvelde, Gijs H M; Wierts, Laura; Lagraauw, H Maxime; Foks, Amanda C; van Santbrink, Peter J; Bot, Ilze; Kuiper, Johan; de Jager, Saskia C A

    2015-01-01

    Modulation of immune responses may form a powerful approach to treat atherosclerosis. It was shown that clearance of apoptotic cells results in tolerance induction to cleared Ags by dendritic cells (DCs); however, this seems impaired in atherosclerosis because Ag-specific tolerance is lacking. This

  2. Another Armament in Gut Immunity: Lymphotoxin-Mediated Crosstalk between Innate Lymphoid and Dendritic Cells

    NARCIS (Netherlands)

    Spits, H.

    2011-01-01

    Innate lymphoid cells (ILCs) are novel players in innate immunity. Tumanov et al. (Tumanov et al., 2011) demonstrate that crosstalk between ILCs and dendritic cells involving membrane-bound lymphotoxin in ILCs and its receptor is critical for protection against colitogenic bacteria

  3. Studies on mRNA electroporation of immature and mature dendritic cells

    DEFF Research Database (Denmark)

    Met, Ozcan; Eriksen, Jens; Svane, Inge Marie

    2008-01-01

    Previous studies have shown that mRNA-electroporated dendritic cells (DCs) are able to process and present tumor-associated antigens, leading to the activation of tumor-specific T cells in vitro and in vivo. However, the optimal maturation state of antigen loading and half-life of the mRNA-transl...

  4. DC-STAMP, a novel multimembrane-spanning molecule preferentially expressed by dendritic cells.

    NARCIS (Netherlands)

    Hartgers, F.C.; Vissers, J.L.M.; Looman, M.W.G.; Zoelen, C. van; Huffine, C.; Figdor, C.G.; Adema, G.J.

    2000-01-01

    Dendritic cells (DC) are unique in their ability to present antigen to naive T cells, and therefore play a central role in the initiation of immune responses. Characterization of DC-specific genes may help to unravel the mechanism underlying their potent antigen presenting capacity. Here we describe

  5. Overlapping, Additive and Counterregulatory Effects of Type II and I Interferons on Myeloid Dendritic Cell Functions

    Directory of Open Access Journals (Sweden)

    Loredana Frasca

    2011-01-01

    Full Text Available Dendritic cells (DCs are central player in immunity by bridging the innate and adaptive arms of the immune system (IS. Interferons (IFNs are one of the most important factors that regulate both innate and adaptive immunity too. Thus, the understanding of how type II and I IFNs modulate the immune-regulatory properties of DCs is a central issue in immunology. In this paper, we will address this point in the light of the most recent literature, also highlighting the controversial data reported in the field. According to the wide literature available, type II as well as type I IFNs appear, at the same time, to collaborate, to induce additive effects or overlapping functions, as well as to counterregulate each one's effects on DC biology and, in general, the immune response. The knowledge of these effects has important therapeutic implications in the treatment of infectious/autoimmune diseases and cancer and indicates strategies for using IFNs as vaccine adjuvants and in DC-based immune therapeutic approaches.

  6. A plasmacytoid dendritic cell (CD123+/CD11c-) based assay system to predict contact allergenicity of chemicals

    Science.gov (United States)

    Ayehunie, Seyoum; Snell, Maureen; Child, Matthew; Klausner, Mitchell

    2009-01-01

    A predictive allergenicity test system for assessing the contact allergenicity of chemicals is needed by the cosmetic and pharmaceutical industry to monitor product safety in the marketplace. Development of such non-animal alternative assay systems for skin sensitization and hazard identification has been pursued by policy makers and regulatory agencies. We investigated whether phenotypic and functional changes to a subset of dendritic cells (DC), plasmacytoid DC (pDC), could be used to identify contact allergens. To achieve this goal, normal human DC were generated from CD34+ progenitor cells and cryopreserved. Frozen DC were thawed and the pDC fraction (CD123+/CD11c-) was harvested using FACS sorting. The pDC were cultured, expanded, and exposed to chemical allergens (N=26) or non-allergens (N=22). Concentrations of each chemical that resulted in >50% viability was determined using FACS analysis of propidium iodide stained cells using pDC from 2-5 donors. Expression of the surface marker, CD86, which has been implicated in dendritic cell maturation, was used as a marker of allergenicity. CD86 expression increased (≥ 1.5 fold) for 25 of 26 allergens (sensitivity = 96%) but did not increase for 19 of 22 non-allergens (specificity = 86%). In a direct comparison to historical data for the regulatory approved, mouse local lymph node assay (LLNA) for 23 allergens and 22 non-allergens, the pDC method had sensitivity and specificity of 96% and 86%, respectively, while the sensitivity and specificity of the LLNA assay was 83% and 82%, respectively. In conclusion, CD86 expression in pDC appears to be a sensitive and specific indicator to identify contact allergenicity. Such an assay method utilizing normal human cells will be useful for high throughput screening of chemicals for allergenicity. PMID:19665512

  7. A plasmacytoid dendritic cell (CD123+/CD11c-) based assay system to predict contact allergenicity of chemicals

    International Nuclear Information System (INIS)

    Ayehunie, Seyoum; Snell, Maureen; Child, Matthew; Klausner, Mitchell

    2009-01-01

    A predictive allergenicity test system for assessing the contact allergenicity of chemicals is needed by the cosmetic and pharmaceutical industry to monitor product safety in the marketplace. Development of such non-animal alternative assay systems for skin sensitization and hazard identification has been pursued by policy makers and regulatory agencies. We investigated whether phenotypic and functional changes to a subset of dendritic cells (DC), plasmacytoid DC (pDC), could be used to identify contact allergens. To achieve this goal, normal human DC were generated from CD34+ progenitor cells and cryopreserved. Frozen DC were thawed and the pDC fraction (CD123+/CD11c-) was harvested using FACS sorting. The pDC were cultured, expanded, and exposed to chemical allergens (N = 26) or non-allergens (N = 22). Concentrations of each chemical that resulted in >50% viability was determined using FACS analysis of propidium iodide stained cells using pDC from 2 to 5 donors. Expression of the surface marker, CD86, which has been implicated in dendritic cell maturation, was used as a marker of allergenicity. CD86 expression increased (≥1.5-fold) for 25 of 26 allergens (sensitivity = 96%) but did not increase for 19 of 22 non-allergens (specificity = 86%). In a direct comparison to historical data for the regulatory approved, mouse local lymph node assay (LLNA) for 23 allergens and 22 non-allergens, the pDC method had sensitivity and specificity of 96% and 86%, respectively, while the sensitivity and specificity of the LLNA assay was 83% and 82%, respectively. In conclusion, CD86 expression in pDC appears to be a sensitive and specific indicator to identify contact allergenicity. Such an assay method utilizing normal human cells will be useful for high throughput screening of chemicals for allergenicity.

  8. IRAK-M expression limits dendritic cell activation and proinflammatory cytokine production in response to Helicobacter pylori.

    Directory of Open Access Journals (Sweden)

    Jessica Shiu

    Full Text Available Helicobacter pylori (H. pylori infects the gastric mucosa and persists for the life of the host. Bacterial persistence may be due to the induction of regulatory T cells (Tregs whichmay have protective effects against other diseases such as asthma. It has been shown that H. pylori modulates the T cell response through dendritic cell reprogramming but the molecular pathways involved are relatively unknown. The goal of this study was to identify critical elements of dendritic cell (DC activation and evaluate potential influence on immune activation. Microarray analysis was used to demonstrate limited gene expression changes in H. pylori stimulated bone marrow derived DCs (BMDCs compared to the BMDCs stimulated with E. coli. IRAK-M, a negative regulator of TLR signaling, was upregulated and we selectedit for investigation of its role in modulating the DC and T cell responses. IRAK-M(-/- and wild type BMDC were compared for their response to H. pylori. Cells lacking IRAK-M produced significantly greater amounts of proinflammatory MIP-2 and reduced amounts of immunomodulatory IL-10 than wild type BMDC. IRAK-M(-/- cells also demonstrated increased MHC II expression upon activation. However, IRAK-M(-/- BMDCs were comparable to wild type BMDCs in inducing T-helper 17 (TH17 and Treg responses as demonstrated in vitro using BMDC CD4+ T cells co-culture assays,and in vivo though the adoptive transfer of CD4(+ FoxP3-GFP T cells into H. pylori infected IRAK-M(-/- mice. These results suggest that H. pylori infection leads to the upregulation of anti-inflammatory molecules like IRAK-M and that IRAK-M has a direct impact on innate functions in DCs such as cytokine and costimulation molecule upregulation but may not affect T cell skewing.

  9. Distinct gut-derived lactic acid bacteria elicit divergent dendritic cell-mediated NK cell responses

    DEFF Research Database (Denmark)

    Fink, Lisbeth Nielsen; Zeuthen, Louise Hjerrild; Christensen, Hanne

    2007-01-01

    Lactic acid bacteria (LAB) are abundant in the gastrointestinal tract where they continuously regulate the immune system. NK cells are potently activated by dendritic cells (DCs) matured by inflammatory stimuli, and NK cells are present in the gut epithelium and in mesenteric lymph nodes......, but it is not known how NK-DC interactions are affected by the predominantly non-pathogenic LAB. We demonstrate that human DCs exposed to different strains of gut-derived LAB consistently induce proliferation, cytotoxicity and activation markers in autologous NK cells. On the contrary, strains of LAB differ greatly...... in their ability to induce DC-dependent IFN-gamma production by NK cells. This suggests that DCs stimulated by gut LAB may expand the pool of NK cells and increase their cytotoxic potential. Specific LAB, inducing high levels of IL-12 in DCs, may promote amplification of a type-1 response via potent stimulation...

  10. Using magnetic resonance imaging to evaluate dendritic cell-based vaccination.

    Directory of Open Access Journals (Sweden)

    Peter M Ferguson

    Full Text Available Cancer immunotherapy with antigen-loaded dendritic cell-based vaccines can induce clinical responses in some patients, but further optimization is required to unlock the full potential of this strategy in the clinic. Optimization is dependent on being able to monitor the cellular events that take place once the dendritic cells have been injected in vivo, and to establish whether antigen-specific immune responses to the tumour have been induced. Here we describe the use of magnetic resonance imaging (MRI as a simple, non-invasive approach to evaluate vaccine success. By loading the dendritic cells with highly magnetic iron nanoparticles it is possible to assess whether the injected cells drain to the lymph nodes. It is also possible to establish whether an antigen-specific response is initiated by assessing migration of successive rounds of antigen-loaded dendritic cells; in the face of a successfully primed cytotoxic response, the bulk of antigen-loaded cells are eradicated on-route to the node, whereas cells without antigen can reach the node unchecked. It is also possible to verify the induction of a vaccine-induced response by simply monitoring increases in draining lymph node size as a consequence of vaccine-induced lymphocyte trapping, which is an antigen-specific response that becomes more pronounced with repeated vaccination. Overall, these MRI techniques can provide useful early feedback on vaccination strategies, and could also be used in decision making to select responders from non-responders early in therapy.

  11. Interleukin 20 regulates dendritic cell migration and expression of co-stimulatory molecules

    DEFF Research Database (Denmark)

    Bech, Rikke; Jalilian, Babak; Agger, Ralf

    2016-01-01

    BACKGROUND: Psoriasis is an inflammatory disease characterized by leukocyte skin infiltration. Interestingly, recent works suggest that the migration of dendritic cells (DCs) is abnormal in psoriatic skin. DCs have significant role in regulating the function of T lymphocytes, at least in part...... influenced by the local environment of cytokines. In psoriatic skin lesions the expression of IL-20 is highly up-regulated. It is unclear if this cytokine has any influence on DCs. METHODS: Here, we investigated the influence of IL-20 in monocyte-derived dendritic cell (MDDCs) in vitro. This work addressed...

  12. Fibroblast and T cells conditioned media induce maturation dendritic cell and promote T helper immune response

    Directory of Open Access Journals (Sweden)

    Masoumeh Asadi

    2012-06-01

    Full Text Available Dendritic cells (DCs induce pathogen-specific T cell responses. We comprehensively studied the effects of addition of maturation stimulus, fibroblasts (fibroblast conditioned medium, PHA activated T cells (T cell conditioned medium, and mixture of fibroblast & PHA activated T cells (FCM-TCCM conditioned media on maturation of DCs. Monocytes were cultured with GM-CSF and IL-4 for five days. Maturation factors included MCM and TNF-α as control group. FCM and TCCM, or FCM-TCCM supernatant were considered as the treatment group. Tumor antigens were added at day five. Matured DCs were harvested at day seven. Phenotypic and functional analyses were carried out using anti (CD14, CD80, CD86, CD83 and HLA-DR monoclonal antibodies. Phagocytic activity, mixed lymphocyte reaction (MLR and cytokine production were also evaluated. At the end of culturing period, significantly fully matured DCs with large amount cytoplasm and copious dendritic projections were found in the presence of MCM, TNF-α with or without FCM, TCCM, FCM as well as TCCM. Flow cytometric analysis revealed that expression of CD14 decreased in particular in treated DCs, at the 5th day and expression of CD80, CD86 and HLA-DR was higher when FCM, TCCM, FCM plus TCCM were added to maturation factor. This study demonstrated that DCs matured with these methods had optimum function in comparison with either factor alone.

  13. DMPD: Plasmacytoid dendritic cells: sensing nucleic acids in viral infection andautoimmune diseases. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 18641647 Plasmacytoid dendritic cells: sensing nucleic acids in viral infection andautoimmune dise... (.csml) Show Plasmacytoid dendritic cells: sensing nucleic acids in viral infection andautoimmune diseases....iral infection andautoimmune diseases. Authors Gilliet M, Cao W, Liu YJ. Publication Nat Rev Immunol. 2008 A

  14. Dendritic cell nuclear protein-1, a novel depression-related protein, upregulates corticotropin-releasing hormone expression

    NARCIS (Netherlands)

    Zhou, Tian; Wang, Shanshan; Ren, Haigang; Qi, Xin-Rui; Luchetti, Sabina; Kamphuis, Willem; Zhou, Jiang-Ning; Wang, Guanghui; Swaab, Dick F.

    2010-01-01

    The recently discovered dendritic cell nuclear protein-1 is the product of a novel candidate gene for major depression. The A allele encodes full-length dendritic cell nuclear protein-1, while the T allele encodes a premature termination of translation at codon number 117 on chromosome 5. In the

  15. Can dendritic cells improve whole cancer cell vaccines based on immunogenically killed cancer cells?

    Science.gov (United States)

    Cicchelero, Laetitia; Denies, Sofie; Devriendt, Bert; de Rooster, Hilde; Sanders, Niek N

    2015-01-01

    Immunogenic cell death (ICD) offers interesting opportunities in cancer cell (CC) vaccine manufacture, as it increases the immunogenicity of the dead CC. Furthermore, fusion of CCs with dendritic cells (DCs) is considered a superior method for generating whole CC vaccines. Therefore, in this work, we determined in naive mice whether immunogenically killed CCs per se (CC vaccine) elicit an antitumoral immune response different from the response observed when immunogenically killed CCs are associated with DCs through fusion (fusion vaccine) or through co-incubation (co-incubation vaccine). After tumor inoculation, the type of immune response in the prophylactically vaccinated mice differed between the groups. In more detail, fusion vaccines elicited a humoral anticancer response, whereas the co-incubation and CC vaccine mainly induced a cellular response. Despite these differences, all three approaches offered a prophylactic protection against tumor development in the murine mammary carcinoma model. In summary, it can be concluded that whole CC vaccines based on immunogenically killed CCs may not necessarily require association with DCs to elicit a protective anticancer immune response. If this finding can be endorsed in other cancer models, the manufacture of CC vaccines would greatly benefit from this new insight, as production of DC-based vaccines is laborious, time-consuming and expensive. PMID:26587315

  16. Targeting regulatory T cells in cancer.

    LENUS (Irish Health Repository)

    Byrne, William L

    2012-01-31

    Infiltration of tumors by regulatory T cells confers growth and metastatic advantages by inhibiting antitumor immunity and by production of receptor activator of NF-kappaB (RANK) ligand, which may directly stimulate metastatic propagation of RANK-expressing cancer cells. Modulation of regulatory T cells can enhance the efficacy of cancer immunotherapy. Strategies include depletion, interference with function, inhibition of tumoral migration, and exploitation of T-cell plasticity. Problems with these strategies include a lack of specificity, resulting in depletion of antitumor effector T cells or global interruption of regulatory T cells, which may predispose to autoimmune diseases. Emerging technologies, such as RNA interference and tetramer-based targeting, may have the potential to improve selectivity and efficacy.

  17. Depletion of cutaneous macrophages and dendritic cells promotes growth of basal cell carcinoma in mice.

    Science.gov (United States)

    König, Simone; Nitzki, Frauke; Uhmann, Anja; Dittmann, Kai; Theiss-Suennemann, Jennifer; Herrmann, Markus; Reichardt, Holger M; Schwendener, Reto; Pukrop, Tobias; Schulz-Schaeffer, Walter; Hahn, Heidi

    2014-01-01

    Basal cell carcinoma (BCC) belongs to the group of non-melanoma skin tumors and is the most common tumor in the western world. BCC arises due to mutations in the tumor suppressor gene Patched1 (Ptch). Analysis of the conditional Ptch knockout mouse model for BCC reveals that macrophages and dendritic cells (DC) of the skin play an important role in BCC growth restraining processes. This is based on the observation that a clodronate-liposome mediated depletion of these cells in the tumor-bearing skin results in significant BCC enlargement. The depletion of these cells does not modulate Ki67 or K10 expression, but is accompanied by a decrease in collagen-producing cells in the tumor stroma. Together, the data suggest that cutaneous macrophages and DC in the tumor microenvironment exert an antitumor effect on BCC.

  18. Involvement of IRF4 dependent dendritic cells in T cell dependent colitis

    DEFF Research Database (Denmark)

    Pool, Lieneke; Rivollier, Aymeric Marie Christian; Agace, William Winston

    in genetically susceptible individuals and pathogenic CD4+ T cells, which accumulate in the inflamed mucosa, are believed to be key drivers of the disease. While dendritic cells (DCs) are important in the priming of intestinal adaptive immunity and tolerance their role in the initiation and perpetuation...... of chronic intestinal inflammation remains unclear. In the current study we used the CD45RBhi T cell transfer model of colitis to determine the role of IRF4 dependent DCs in intestinal inflammation. In this model naïve CD4+ T cells when transferred into RAG-/- mice, proliferate and expand in response...... to bacterial derived luminal antigen, localize to the intestinal mucosa and induce colitis. Adoptive transfer of naïve T cells into CD11cCre.IRF4fl/fl.RAG-1-/- mice resulted in reduced monocyte recruitment to the intestine and mesenteric lymph nodes (MLN) compared to Cre- controls. Inflammatory cytokines...

  19. Role of Nuclear Factor (Erythroid-Derived 2-Like 2 Signaling for Effects of Fumaric Acid Esters on Dendritic Cells

    Directory of Open Access Journals (Sweden)

    Anna Hammer

    2017-12-01

    Full Text Available To date, the intracellular signaling pathways involved in dendritic cell (DC function are poorly understood. The antioxidative transcription factor nuclear factor (erythroid-derived 2-like 2 (Nrf2 has been shown to affect maturation, function, and subsequent DC-mediated T cell responses of murine and human DCs. In experimental autoimmune encephalomyelitis (EAE, as prototype animal model for a T helper cell-mediated autoimmune disease, antigen presentation, cytokine production, and costimulation by DCs play a major role. We explore the role of Nrf2 in DC function, and DC-mediated T cell responses during T cell-mediated autoimmunity of the central nervous system using genetic ablation and pharmacological activation in mice and men to corroborate our data in a translational setting. In murine and human DCs, monomethyl fumarate induced Nrf2 signaling inhibits DC maturation and DC-mediated T cell proliferation by reducing inflammatory cytokine production and expression of costimulatory molecules. In contrast, Nrf2-deficient DCs generate more activated T helper cells (Th1/Th17 but fewer regulatory T cells and foster T cell proliferation. Transfer of DCs with Nrf2 activation during active EAE reduces disease severity and T cell infiltration. Our data demonstrate that Nrf2 signaling modulates autoimmunity in murine and human systems via inhibiting DC maturation and function thus shedding further light on the mechanism of action of antioxidative stress pathways in antigen-presenting cells.

  20. Perspectives on Regulatory T Cell Therapies

    OpenAIRE

    Probst-Kepper, Michael; Kröger, Andrea; Garritsen, Henk S.P.; Buer, Jan

    2009-01-01

    Adoptive transfer in animal models clearly indicate an essential role of CD4+ CD25+ FOXP3+ regulatory T (Treg) cells in prevention and treatment of autoimmune and graft-versus-host disease. Thus, Treg cell therapies and development of drugs that specifically enhance Treg cell function and development represent promising tools to establish dominant tolerance. So far, lack of specific markers to differentiate human Treg cells from activated CD4+ CD25+ effector T cells, which also express FOXP3 ...

  1. EVIR: chimeric receptors that enhance dendritic cell cross-dressing with tumor antigens.

    Science.gov (United States)

    Squadrito, Mario Leonardo; Cianciaruso, Chiara; Hansen, Sarah K; De Palma, Michele

    2018-03-01

    We describe a lentivirus-encoded chimeric receptor, termed extracellular vesicle (EV)-internalizing receptor (EVIR), which enables the selective uptake of cancer-cell-derived EVs by dendritic cells (DCs). The EVIR enhances DC presentation of EV-associated tumor antigens to CD8 + T cells primarily through MHCI recycling and cross-dressing. EVIRs should facilitate exploring the mechanisms and implications of horizontal transfer of tumor antigens to antigen-presenting cells.

  2. EMT factor Zeb1 depletion in dendritic cells enhances Helminth clearance in mice by increasing Th2 cell differentiation

    Directory of Open Access Journals (Sweden)

    Shuchi Smita

    2017-10-01

    Full Text Available Dendritic cells are professional antigen presenting cells that act as bridging link between innate and adaptive immune system. They are equipped with pathogen recognition receptors (PRR to identify the pathogen associated molecular pattern (PAMPS on any antigen. DCs elicit an immune response through polarizing T cells towards various subtypes like Th1, Th2 & Tregs. Though DC-T cell interaction has been widely studied, but how this single DC molecule amalgamate various transcriptional signals for translating the message to the T cells and induce diverse immunological responses still needs to be unraveled. Therefore to identify the role of transcription factor in immune programming we have targeted the largest member of TFs family, Zinc Finger Transcription Factors (ZF-TFs. Among various ZF-TFs we have narrowed our study to three interesting candidates Zeb1, Zeb2 and Zbtb10 based on their expression in DCs from an unpublished microarray data. Here in this study we have tried to understand the role of Zeb1, master regulator of EMT program in orchestrating DC responses. Zeb1 links the epithelial – mesenchymal transition and has been widely studied molecule in cancer biology. Except for the fact that it act as transcriptional repressor and represses IL2 gene promoter no other reports are available in immune biology, thereby rendering it a perfect candidate to be used for detailed characterization in dendritic cells. In our study, we found that Zeb1 depleted CD8α+DCs shows an increase in co-stimulatory marker like CD80 & CD86 whereas there is a decrease in MHC class I & II molecule. Thereafter at transcript & protein level we found decrease in pro-inflammatory & anti-inflammatory cytokine like IL6 & IL10 respectively, the bioactive form of IL12 i.e. IL12p70 which polarizes T cells towards Th1 response showed a significant decrease in bio-plex when compared with control CD8α+DCs. The regulatory markers which develop regulatory T cells like Pdl1, IL

  3. Dendritic cell neurofibroma sine pseudorosettes: report of a case with a granulomatous appearance.

    Science.gov (United States)

    Petersson, Fredrik

    2011-10-01

    An unusual variant of dendritic cell neurofibroma is reported. In contrast to previous cases, the formation of pseudorosettes was lacking. The tumor was located on the anterior aspect of the thigh in a previously healthy 71-year-old woman with no evidence of neurofibromatosis. The tumor was composed of type-1 and type-2 cells, which were immunoreactive for S-100 protein and CD57. The granulomatous appearance was due to the zonal accumulation of CD34-positive dendritic cells and type-1 cells in a serpiginous fashion surrounding large areas with lesser cellularity featuring type-2 cells with scattered type-1 cells arranged in a haphazard fashion. Intralesional small neurites positive for neurofilament and perilesional perineural cells positive for epithelial membrane antigen were documented immunohistochemically.

  4. Vascular endothelial growth factor impairs the functional ability of dendritic cells through Id pathways

    International Nuclear Information System (INIS)

    Laxmanan, Sreenivas; Robertson, Stuart W.; Wang Enfeng; Lau, Julie S.; Briscoe, David M.; Mukhopadhyay, Debabrata

    2005-01-01

    Vascular endothelial growth factor (VEGF) is an angiogenic cytokine that plays an important role in tumor growth and progression. Recent evidence suggests an alternate, albeit indirect, role of VEGF on host immune response to tumors. VEGF appears to diminish host immunity by altering the function of major antigen-presenting cells such as dendritic cells (DCs) [D.I. Gabrilovich, T. Ishida, S. Nadaf, J.E. Ohm, D.P. Carbone, Antibodies to vascular endothelial growth factor enhance the efficacy of cancer immunotherapy by improving endogenous dendritic cell function, Clin. Cancer Res. 5 (1999) 2963-2970, D. Gabrilovich, T. Ishida, T. Oyama, S. Ran, V. Kravtsov, S. Nadaf, D.P. Carbone, Vascular endothelial growth factor inhibits the development of dendritic cells and dramatically affects the differentiation of multiple hematopoietic lineages in vivo, Blood 92 (1998) 4150-4166, T. Oyama, S. Ran, T. Ishida, S. Nadaf, L. Kerr, D.P. Carbone, D.I. Gabrilovich, Vascular endothelial growth factor affects dendritic cell maturation through the inhibition of nuclear factor-kappa B activation in hemopoietic progenitor cells, J. Immunol. 160 (1998) 1224-1232.]. DCs are prime initiators of host immunity as they are known to activate both primary as well as secondary immune responses [J. Banchereau, F. Briere, C. Caux, J. Davoust, S. Lebecque, Y.J. Liu, B. Pulendran, K. Palucka, Immunobiology of dendritic cells, Ann. Rev. Immunol. 18 (2000) 767-811.]. However, the exact nature of how VEGF suppresses DC function is not fully clear. In this report, we show that DCs cultured in the presence of VEGF are less potent in stimulating antigen-specific T-cells. Furthermore, by using DCs derived from Id1 -/- mice that are defective in Flt-1 signaling, we demonstrated that the inhibitory function of VEGF on DC function is most likely mediated by Flt-1. Thus, the role of VEGF in downregulating host immunity may highlight a unique role of VEGF in the pathogenesis of cancer

  5. CD4-regulatory cells in COPD patients

    DEFF Research Database (Denmark)

    Smyth, Lucy J C; Starkey, Cerys; Vestbo, Jørgen

    2007-01-01

    BACKGROUND: The numbers of airway CD8 and B lymphocytes are increased in COPD patients, suggesting an autoimmune process. CD4-regulatory T cells control autoimmunity but have not been studied in patients with COPD. OBJECTIVE: To compare T-regulatory cell numbers in the BAL from COPD patients......, smokers with normal lung function, and healthy nonsmokers (HNS). METHODS: BAL and peripheral blood mononuclear cell (PBMC) samples were obtained from 26 COPD patients, 19 smokers, and 8 HNS. Flow cytometry was performed for regulatory phenotypic markers. RESULTS: COPD patients had increased BAL CD8...... numbers compared to smokers and HNS. CD4 numbers were similar between groups. There was increased BAL CD4CD25(bright) expression in smokers (median 28.8%) and COPD patients (median 23.1%) compared to HNS (median 0%). Increased FoxP3 expression was confirmed in BAL CD4CD25(bright) cells. BAL CD4CD25 cells...

  6. Murine Th9 cells promote the survival of myeloid dendritic cells in cancer immunotherapy.

    Science.gov (United States)

    Park, Jungsun; Li, Haiyan; Zhang, Mingjun; Lu, Yong; Hong, Bangxing; Zheng, Yuhuan; He, Jin; Yang, Jing; Qian, Jianfei; Yi, Qing

    2014-08-01

    Dendritic cells (DCs) are professional antigen-presenting cells to initiate immune responses, and DC survival time is important for affecting the strength of T-cell responses. Interleukin (IL)-9-producing T-helper (Th)-9 cells play an important role in anti-tumor immunity. However, it is unclear how Th9 cells communicate with DCs. In this study, we investigated whether murine Th9 cells affected the survival of myeloid DCs. DCs derived from bone marrow of C57BL/6 mice were cocultured with Th9 cells from OT-II mice using transwell, and the survival of DCs was examined. DCs cocultured with Th9 cells had longer survival and fewer apoptotic cells than DCs cultured alone in vitro. In melanoma B16-OVA tumor-bearing mice, DCs conditioned by Th9 cells lived longer and induced stronger anti-tumor response than control DCs did in vivo. Mechanistic studies revealed that IL-3 but not IL-9 secreted by Th9 cells was responsible for the prolonged survival of DCs. IL-3 upregulated the expression of anti-apoptotic protein Bcl-xL and activated p38, ERK and STAT5 signaling pathways in DCs. Taken together, our data provide the first evidence that Th9 cells can promote the survival of DCs through IL-3, and will be helpful for designing Th9 cell immunotherapy and more effective DC vaccine for human cancers.

  7. Modulatory effects of Echinacea purpurea extracts on human dendritic cells: a cell- and gene-based study.

    Science.gov (United States)

    Wang, Chien-Yu; Chiao, Ming-Tsang; Yen, Po-Jen; Huang, Wei-Chou; Hou, Chia-Chung; Chien, Shih-Chang; Yeh, Kuo-Chen; Yang, Wen-Ching; Shyur, Lie-Fen; Yang, Ning-Sun

    2006-12-01

    Echinacea spp. are popularly used as an herbal medicine or food supplement for enhancing the immune system. This study shows that plant extracts from root [R] and stem plus leaf [S+L] tissues of E. purpurea exhibit opposite (enhancing vs inhibitory) modulatory effects on the expression of the CD83 marker in human dendritic cells (DCs), which are known as professional antigen-presenting cells. We developed a function-targeted DNA microarray system to characterize the effects of phytocompounds on human DCs. Down-regulation of mRNA expression of specific chemokines (e.g., CCL3 and CCL8) and their receptors (e.g., CCR1 and CCR9) was observed in [S+L]-treated DCs. Other chemokines and regulatory molecules (e.g., CCL4 and CCL2) involved in the c-Jun pathway were found to be up-regulated in [R]-treated DCs. This study, for the first time, demonstrates that E. purpurea extracts can modulate DC differentiation and expression of specific immune-related genes in DCs.

  8. Redox regulation of stress signals: possible roles of dendritic stellate TRX producer cells (DST cell types).

    Science.gov (United States)

    Yodoi, Junji; Nakamura, Hajime; Masutani, Hiroshi

    2002-01-01

    Thioredoxin (TRX) is a 12 kDa protein with redox-active dithiol (Cys-Gly-Pro-Cys) in the active site. TRX is induced by a variety of stresses including viral infection and inflammation. The promoter sequences of the TRX gene contain a series of stress-responsive elements including ORE, ARE, XRE, CRE and SP-1. TRX promotes DNA binding of transcription factors such as NF-kappaB, AP-1 and p53. TRX interacts with target proteins modulating the activity of those proteins. We have identified TRX binding protein-2 (TBP-2), which was identical to vitamin D3 up-regulated protein 1 (VDUP1). Potential action of TBP-2/VDUP1 as a redox-sensitive tumor suppressor will be discussed. There is accumulating evidence for the involvement of TRX in the protection against infectious and inflammatory disorders. We will discuss the role of TRX-dependent redox regulation of the host defense mechanism, in particular its relation to the emerging concept of constitutive and/or inducible TRX on special cell types with dendritic and stellate morphology in the immune, endocrine and nervous systems, which we provisionally designate as dendritic stellate TRX producer cells (DST cell types).

  9. A Lactobacillus rhamnosus strain induces a heme oxygenase dependent increase in Foxp3+ regulatory T cells.

    Directory of Open Access Journals (Sweden)

    Khalil Karimi

    Full Text Available We investigated the consequences of feeding with a Lactobacillus species on the immune environment in GALT, and the role of dendritic cells and heme oxygenase-1 in mediating these responses. Feeding with a specific strain of Lactobacillus rhamnosus induced a significant increase in CD4+CD25+Foxp3+ functional regulatory T cells in GALT. This increase was greatest in the mesenteric lymph nodes and associated with a marked decrease in TNF and IFNγ production. Dendritic cell regulatory function and HO-1 expression was also increased. The increase in Foxp3+ T cells could be prevented by treatment with a heme oxygenase inhibitor. However, neither inhibition of heme oxygenase nor blockade of IL-10 and TGFβ prevented the inhibition of inflammatory cytokine production. In conclusion Lactobacillus feeding induced a tolerogenic environment in GALT. HO-1 was critical to the enhancement of Foxp3+ regulatory T cells while additional, as yet unknown, pathways were involved in the down-regulation of inflammatory cytokine production by T cells.

  10. Critical role of dendritic cells in T cell retention in the interfollicular region of Peyer's patches.

    Science.gov (United States)

    Obata, Takashi; Shibata, Naoko; Goto, Yoshiyuki; Ishikawa, Izumi; Sato, Shintaro; Kunisawa, Jun; Kiyono, Hiroshi

    2013-07-15

    Peyer's patches (PPs) simultaneously initiate active and quiescent immune responses in the gut. The immunological function is achieved by the rigid regulation of cell distribution and trafficking, but how the cell distribution is maintained remains to be elucidated. In this study, we show that binding of stromal cell-derived lymphoid chemokines to conventional dendritic cells (cDCs) is essential for the retention of naive CD4(+) T cells in the interfollicular region (IFR) of PPs. Transitory depletion of CD11c(high) cDCs in mice rapidly impaired the IFR structure in the PPs without affecting B cell follicles or germinal centers, lymphoid chemokine production from stromal cells, or the immigration of naive T cells into the IFRs of PPs. The cDC-orchestrated retention of naive T cells was mediated by heparinase-sensitive molecules that were expressed on cDCs and bound the lymphoid chemokine CCL21 produced from stromal cells. These data collectively reveal that interactions among cDCs, stromal cells, and naive T cells are necessary for the formation of IFRs in the PPs.

  11. The SNARE VAMP7 Regulates Exocytic Trafficking of Interleukin-12 in Dendritic Cells

    Directory of Open Access Journals (Sweden)

    Giulia Chiaruttini

    2016-03-01

    Full Text Available Interleukin-12 (IL-12, produced by dendritic cells in response to activation, is central to pathogen eradication and tumor rejection. The trafficking pathways controlling spatial distribution and intracellular transport of IL-12 vesicles to the cell surface are still unknown. Here, we show that intracellular IL-12 localizes in late endocytic vesicles marked by the SNARE VAMP7. Dendritic cells (DCs from VAMP7-deficient mice are partially impaired in the multidirectional release of IL-12. Upon encounter with antigen-specific T cells, IL-12-containing vesicles rapidly redistribute at the immune synapse and release IL-12 in a process entirely dependent on VAMP7 expression. Consistently, acquisition of effector functions is reduced in T cells stimulated by VAMP7-null DCs. These results provide insights into IL-12 intracellular trafficking pathways and show that VAMP7-mediated release of IL-12 at the immune synapse is a mechanism to transmit innate signals to T cells.

  12. Progress on the development of human in vitro dendritic cell based assays for assessment of the sensitizing potential of a compound

    International Nuclear Information System (INIS)

    Galvao dos Santos, G.; Reinders, J.; Ouwehand, K.; Rustemeyer, T.; Scheper, R.J.; Gibbs, S.

    2009-01-01

    Allergic contact dermatitis is the result of an adaptive immune response of the skin to direct exposure to an allergen. Since many chemicals are also allergens, European regulations require strict screening of all ingredients in consumer products. Until recently, identifying a potential allergen has completely relied on animal testing (e.g.: Local Lymph Node Assay). In addition to the ethical problems, both the 7th Amendment to the Cosmetics Directive and REACH have stimulated the development of alternative tests for the assessment of potential sensitizers. This review is aimed at summarising the progress on cell based assays, in particular dendritic cell based assays, being developed as animal alternatives. Primary cells (CD34 + derived dendritic cells, monocyte derived dendritic cells) as well as dendritic cell-like cell lines (THP-1, U-937, MUTZ-3, KG-1, HL-60, and K562) are extensively described along with biomarkers such as cell surface markers, cytokines, chemokines and kinases. From this review, it can be concluded that no single cell based assay nor single marker is yet able to distinguish all sensitizers from non-sensitizers in a test panel of chemicals, nor is it possible to rank the sensitizing potential of the test chemicals. This suggests that sensitivity and specificity may be increased by a tiered assay approach. Only a limited number of genomic and proteomic studies have been completed until now. Such studies have the potential to identify novel biomarkers for inclusion in future assay development. Although progress is promising, this review suggests that it may be difficult to meet the up and coming European regulatory deadlines.

  13. In situ concentration cartography in the neighborhood of dendrites growing in lithium/polymer-electrolyte/lithium cells

    Energy Technology Data Exchange (ETDEWEB)

    Brissot, C.; Rosso, M.; Chazalviel, J.N.; Lascaud, S.

    1999-12-01

    The authors report on three different in situ and ex situ concentration measurement methods in symmetric lithium/polymer-electrolyte/lithium cells. The results were examined on the basis of a simple calculation of ionic concentration within the electrolyte, in the case where no dendrite is observed, this calculation accounts quantitatively for all experimental results. In the case of dendritic growth, the authors can measure the concentration distribution around the dendrites; this permits correlation of the active parts of the electrodes and of the growing dendrites with local ionic depletion in the vicinity of these active parts.

  14. Immunotoxicity of organophosphate flame retardants TPHP and TDCIPP on murine dendritic cells in vitro

    NARCIS (Netherlands)

    Canbaz, Derya; Logiantara, Adrian; van Ree, Ronald; van Rijt, Leonie S.

    2017-01-01

    Organophosphate flame retardants (PFRs) are commonly used as alternatives for the banned polybrominated diphenyl ethers (PBDEs) and are ubiquitously detected in indoor dust. PFRs can be potentially hazardous to respiratory health via the inhalation of house dust. Dendritic cells (DCs) are crucial in

  15. Selection of probiotic bacteria for prevention of allergic diseases: immunomodulation of neonatal dendritic cells

    NARCIS (Netherlands)

    Niers, L. E. M.; Hoekstra, M. O.; Timmerman, H. M.; van Uden, N. O.; de Graaf, P. M. A.; Smits, H. H.; Kimpen, J. L. L.; Rijkers, G. T.

    2007-01-01

    Modification of intestinal microbiota early in life by administration of probiotic bacteria may be a potential approach to prevent allergic disease. To select probiotic bacteria for in vivo purposes, we investigated the capacity of probiotic bacteria to interact with neonatal dendritic cells (DC)

  16. Saponin-based adjuvants induce cross-presentation in dendritic cells by intracellular lipid body formation

    NARCIS (Netherlands)

    Brok, M.H. den; Bull, C.; Wassink, M.; Graaf, A.M.A. de; Wagenaars, J.A.L.; Minderman, M.; Thakur, M.; Amigorena, S.; Rijke, E.O.; Schrier, C.C.; Adema, G.J.

    2016-01-01

    Saponin-based adjuvants (SBAs) are being used in animal and human (cancer) vaccines, as they induce protective cellular immunity. Their adjuvant potency is a factor of inflammasome activation and enhanced antigen cross-presentation by dendritic cells (DCs), but how antigen cross-presentation is

  17. Consolidative dendritic cell-based immunotherapy elicits cytotoxicity against malignant mesothelioma.

    NARCIS (Netherlands)

    Hegmans, J.P.; Veltman, J.D.; Lambers, M.E.; Vries, I.J.M. de; Figdor, C.G.; Hendriks, R.W.; Hoogsteden, H.C.; Lambrecht, B.N.; Aerts, J.G.

    2010-01-01

    RATIONALE: We previously demonstrated that dendritic cell-based immunotherapy induced protective antitumor immunity with a prolonged survival rate in mice. However, the clinical relevance is still in question. To examine this, we designed a clinical trial using chemotherapy followed by

  18. Cdc42-dependent leading edge coordination is essential for interstitial dendritic cell migration

    DEFF Research Database (Denmark)

    Lammermann, Tim; Renkawitz, Jorg; Wu, Xunwei

    2009-01-01

    Mature dendritic cells (DCs) moving from the skin to the lymph node are a prototypic example of rapidly migrating amoeboid leukocytes. Interstitial DC migration is directionally guided by chemokines, but independent of specific adhesive interactions with the tissue as well as pericellular proteol...

  19. Tick saliva inhibits dendritic cell migration, maturation and function, while promoting development of Th2 responses

    Czech Academy of Sciences Publication Activity Database

    Skallová, Anna; Iezzi, G.; Ampenberger, F.; Kopf, M.; Kopecký, Jan

    2008-01-01

    Roč. 180, č. 9 (2008), s. 6186-9192 ISSN 0022-1767 R&D Projects: GA ČR GA524/05/0811; GA MŠk(CZ) LC06009 Institutional research plan: CEZ:AV0Z60220518 Keywords : dendritic cell * tick saliva * Th2 * immune responses Subject RIV: EC - Immunology Impact factor: 6.000, year: 2008

  20. Effect of tick saliva on immune interactions between Borrelia afzelii and murine dendritic cells

    Czech Academy of Sciences Publication Activity Database

    Slámová, M.; Skallová, A.; Páleníková, J.; Kopecký, Jan

    2011-01-01

    Roč. 33, č. 12 (2011), 654-660 ISSN 0141-9838 R&D Projects: GA AV ČR IAA600960811; GA MŠk(CZ) LC06009 Institutional research plan: CEZ:AV0Z60220518 Keywords : Borrelia * dendritic cell * immune modulation * Ixodes ricinus Subject RIV: EC - Immunology Impact factor: 2.601, year: 2011

  1. Autocrine CCL19 blocks dendritic cell migration toward weak gradients of CCL21

    DEFF Research Database (Denmark)

    Hansen, Morten; Met, Özcan; Larsen, Niels Bent

    2016-01-01

    Background aims. Maturation of dendritic cells (DCs) induces their homing from peripheral to lymphatic tissues guided by CCL21. However, in vitro matured human monocyte-derived DC cancer vaccines injected intradermally migrate poorly to lymph nodes (LNs). In vitro maturation protocols generate DCs...

  2. Poly-I:C Decreases Dendritic Cell Viability Independent of PKR Activation

    DEFF Research Database (Denmark)

    Larsen, Hjalte List; Pedersen, Anders Elm

    2012-01-01

    Vaccination with tumor-antigen pulsed, monocyte-derived dendritic cells (DCs) has emerged as a promising strategy in cancer immunotherapy. The standard DC maturation cocktail consists of a combination of tumor necrosis factor-α (TNF-α)/interleukin (IL)-1β/IL-6 and prostaglandin E2 (PGE2...

  3. Tick sialostatins L and L2 differentially influence dendritic cell responses to Borrelia spirochetes

    Czech Academy of Sciences Publication Activity Database

    Lieskovská, Jaroslava; Páleníková, Jana; Langhansová, Helena; Chagas, A. C.; Calvo, E.; Kotsyfakis, Michalis; Kopecký, Jan

    2015-01-01

    Roč. 8, MAY 15 2015 (2015), s. 275 ISSN 1756-3305 R&D Projects: GA ČR GAP302/12/2208 Institutional support: RVO:60077344 Keywords : Dendritic cell s * Borrelia burgdorferi * Tick cystatin * Signalling Subject RIV: EC - Immunology Impact factor: 3.234, year: 2015

  4. Yersinia enterocolitica YopP inhibits MAP kinase-mediated antigen uptake in dendritic cells

    Czech Academy of Sciences Publication Activity Database

    Autenrieth, S. E.; Adkins, Irena; Rösemann, R.; Gunst, D.; Zahir, N.; Kracht, M.; Ruckdeschel, K.; Wagner, H.; Borgmann, S.; Autenrieth, I. B.

    2007-01-01

    Roč. 9, č. 2 (2007), s. 425-437 ISSN 1462-5814 Institutional research plan: CEZ:AV0Z50200510 Keywords : yersinia enterocolitica * dendritic cell s * immunity Subject RIV: EC - Immunology Impact factor: 5.293, year: 2007

  5. Preclinical Evaluation of Novel Dendritic Cell-Based Prostate Cancer Vaccines

    Science.gov (United States)

    2008-01-01

    payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this...in melanoma patients is determined by their maturation state. Cancer Res 2003;63:12–7. 34. Nestle FO, Banchereau J, Hart D. Dendritic cells: on the

  6. Identification of a microRNA signature in dendritic cell vaccines for cancer immunotherapy

    DEFF Research Database (Denmark)

    Holmstrøm, Kim; Pedersen, Ayako Wakatsuki; Claesson, Mogens Helweg

    2010-01-01

    Dendritic cells (DCs) exposed to tumor antigens followed by treatment with T(h)1-polarizing differentiation signals have paved the way for the development of DC-based cancer vaccines. Critical parameters for assessment of the optimal functional state of DCs and prediction of the vaccine potency o...

  7. Activation of toll-like receptors and dendritic cells by a broad range of bacterial molecules

    NARCIS (Netherlands)

    Boele, L.C.L.; Bajramovic, J.J.; Vries, A.M.M.B.C. de; Voskamp-Visser, I.A.I.; Kaman, W.E.; Kleij, D. van der

    2009-01-01

    Activation of pattern recognition receptors such as Toll-like receptors (TLRs) by pathogens leads to activation and maturation of dendritic cells (DC), which orchestrate the development of the adaptive immune response. To create an overview of the effects of a broad range of pathogenic bacteria,

  8. Ixodes ricinus tick saliva modulates tick-borne encephalitis virus infection of dendritic cells

    Czech Academy of Sciences Publication Activity Database

    Fialová, Anna; Cimburek, Zdeněk; Iezzi, G.; Kopecký, Jan

    2010-01-01

    Roč. 12, č. 7 (2010), s. 580-585 ISSN 1286-4579 R&D Projects: GA AV ČR IAA600960811 Institutional research plan: CEZ:AV0Z60220518; CEZ:AV0Z50200510 Keywords : Tick-borne encephalitis virus * Dendritic cell * Tick saliva * Ixodes ricinus Subject RIV: EC - Immunology Impact factor: 2.726, year: 2010

  9. DYSFUNCTION OF MONOCYTES AND DENDRITIC CELLS IN PATIENTS WITH PREMATURE OVARIAN FAILURE

    NARCIS (Netherlands)

    HOEK, A; VAN KASTEREN, Y; DE HAAN-MEULMAN, M; SCHOEMAKER, J; DREXHAGE, HA

    1993-01-01

    PROBLEM: Due to the presence of ovarian antibodies it has been suggested that premature ovarian failure (POF) belongs to the autoimmune endocrinopathies. Monocytes and the monocyte-derived dendritic cells play a prominent role in the initial stages of endocrine autoimmune reactions: the accumulation

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

    Directory of Open Access Journals (Sweden)

    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.

  11. Differential CCR7 Targeting in Dendritic Cells by Three Naturally Occurring CC-Chemokines

    DEFF Research Database (Denmark)

    Hjorto, Gertrud M.; Larsen, Olav; Steen, Anne

    2016-01-01

    The CCR7 ligands CCL19 and CCL21 are increasingly recognized as functionally different (biased). Using mature human dendritic cells (DCs), we show that CCL19 is more potent than CCL21 in inducing 3D chemotaxis. Intriguingly, CCL21 induces prolonged and more efficient ERK1/2 activation compared...

  12. Protein Tyrosine Phosphatase PTPRS Is an Inhibitory Receptor on Human and Murine Plasmacytoid Dendritic Cells

    NARCIS (Netherlands)

    Bunin, A.; Sisirak, V.; Ghosh, H.S.; Grajkowska, L.T.; Hou, Z.E.; Miron, M.; Yang, C.; Ceribelli, M.; Uetani, N.; Chaperot, L.; Plumas, J.; Hendriks, W.J.; Tremblay, M.L.; Hacker, H.; Staudt, L.M.; Green, P.H.; Bhagat, G.; Reizis, B.

    2015-01-01

    Plasmacytoid dendritic cells (pDCs) are primary producers of type I interferon (IFN) in response to viruses. The IFN-producing capacity of pDCs is regulated by specific inhibitory receptors, yet none of the known receptors are conserved in evolution. We report that within the human immune system,

  13. Dendritic cells sensitize TCRs through self-MHC-mediated Src family kinase activation

    Czech Academy of Sciences Publication Activity Database

    Meraner, P.; Hořejší, Václav; Wolpl, A.; Fischer, G.F.; Stingl, G.; Maurer, D.

    2007-01-01

    Roč. 178, č. 4 (2007), s. 2262-2271 ISSN 0022-1767 Institutional research plan: CEZ:AV0Z50520514 Keywords : TCR * dendritic cells * Src kinases Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 6.068, year: 2007

  14. Tick saliva suppresses IFN signalling in dendritic cells upon Borrelia afzelii infection

    Czech Academy of Sciences Publication Activity Database

    Lieskovská, Jaroslava; Kopecký, Jan

    2012-01-01

    Roč. 34, č. 1 (2012), s. 32-39 ISSN 0141-9838 R&D Projects: GA MŠk(CZ) LC06009 Institutional support: RVO:60077344 Keywords : Borrelia * dendritic cells * interferon signalling * tick saliva Subject RIV: EC - Immunology Impact factor: 2.208, year: 2012

  15. Generation of dendritic cells for immunotherapy is minimally impaired by granulocytes in the monocyte preparation

    NARCIS (Netherlands)

    ten Brinke, Anja; Karsten, Miriam L.; Dieker, Miranda C.; Zwaginga, Jaap Jan; Vrielink, Hans; van Ham, S. Marieke

    2006-01-01

    The growing number of clinical studies, using monocyte-derived DC therapy, requires protocols where a sufficient number of dendritic cell (DCs) are produced according to current Good Manufacturing Practice guidelines. Therefore, a closed culture system for the generation of DCs is inevitable. One

  16. Tick salivary cystatin sialostatin L2 suppresses IFN responses in mouse dendritic cells

    Czech Academy of Sciences Publication Activity Database

    Lieskovská, Jaroslava; Páleníková, Jana; Širmarová, J.; Elsterová, Jana; Kotsyfakis, Michalis; Chagas, A. C.; Calvo, E.; Růžek, Daniel; Kopecký, Jan

    2015-01-01

    Roč. 37, č. 2 (2015), s. 70-78 ISSN 0141-9838 R&D Projects: GA ČR GAP302/12/2208 Institutional support: RVO:60077344 Keywords : Tick * Dendritic cells * Interferon * Cystatin Subject RIV: EC - Immunology Impact factor: 1.917, year: 2015

  17. Studies on the control mechanism and the degenerative immune function of dendritic cells using radiation

    International Nuclear Information System (INIS)

    Yee, Sung Tae; Kim, Jong Jin; Choi, Ji Na; Park, Jung Eun; Jeong, Young Ran

    2010-05-01

    Dendritic cells are actively used as cellular adjuvant in cancer immunotherapy. However, although DC immunotherapies primarily target the elderly population, little is known about the effect of aging on DC functions. Here, we compared the T-cell stimulation, cytokine production, and costimulatory molecule expression of spleen or bone marrow-derived CD11c + DCs of C57BL/6 mice. In the first year, we compared various function of dendritic cells isolated from young and gamma-irradiated 57BL/6 mice(5 weeks after γ-radiation) for the development of aging models using radiation. In the second year, we also compared the function of spleen- and bone marrow-derived dendritic cells of young(2-3 months) and old(23-24 months) 57BL/6 mice. And we studied the differences of spleen- and bone marrow-derived dendritic cells of young and gamma-irradiated 57BL/6 mice(2, 4, 6 months after γ-radiation) for the development of aging models in third year. And we obtained various differences between spleen- and bone marrow-derived dendritic cells of normal and old(23-24 months) or γ-irradiated 57BL/6 mice. It is possible to use our results as age-associated model for modulation of the declined immunity and hematopoiesis for treatment of cancer, adult diseases and stress in aging. Such studies on the mechanism of aging model would further lead to new avenues for the development of functional foods which effect such as pathogenesis, inflammatory and autoimmune disorders. It will contributed to activation of related industry conforming quality and diversity of radiation industry. The techniques developed in our research may provide novel therapeutic modalities for age-associated immune dysfunctions

  18. Studies on the control mechanism and the degenerative immune function of dendritic cells using radiation

    Energy Technology Data Exchange (ETDEWEB)

    Yee, Sung Tae; Kim, Jong Jin; Choi, Ji Na; Park, Jung Eun; Jeong, Young Ran [Sunchon National University, Sunchon (Korea, Republic of)

    2010-05-15

    Dendritic cells are actively used as cellular adjuvant in cancer immunotherapy. However, although DC immunotherapies primarily target the elderly population, little is known about the effect of aging on DC functions. Here, we compared the T-cell stimulation, cytokine production, and costimulatory molecule expression of spleen or bone marrow-derived CD11c{sup +} DCs of C57BL/6 mice. In the first year, we compared various function of dendritic cells isolated from young and gamma-irradiated 57BL/6 mice(5 weeks after {gamma}-radiation) for the development of aging models using radiation. In the second year, we also compared the function of spleen- and bone marrow-derived dendritic cells of young(2-3 months) and old(23-24 months) 57BL/6 mice. And we studied the differences of spleen- and bone marrow-derived dendritic cells of young and gamma-irradiated 57BL/6 mice(2, 4, 6 months after {gamma}-radiation) for the development of aging models in third year. And we obtained various differences between spleen- and bone marrow-derived dendritic cells of normal and old(23-24 months) or {gamma}-irradiated 57BL/6 mice. It is possible to use our results as age-associated model for modulation of the declined immunity and hematopoiesis for treatment of cancer, adult diseases and stress in aging. Such studies on the mechanism of aging model would further lead to new avenues for the development of functional foods which effect such as pathogenesis, inflammatory and autoimmune disorders. It will contributed to activation of related industry conforming quality and diversity of radiation industry. The techniques developed in our research may provide novel therapeutic modalities for age-associated immune dysfunctions

  19. Regulatory T-cells and autoimmunity.

    LENUS (Irish Health Repository)

    Ni Choileain, Niamh

    2012-02-03

    Approximately 20% of the population is affected by autoimmune or inflammatory diseases mediated by an abnormal immune response. A characteristic feature of autoimmune disease is the selective targeting of a single cell type, organ or tissue by certain populations of autoreactive T-cells. Examples of such diseases include rheumatoid arthritis, insulin-dependent diabetes mellitus, and systemic lupus erythematosus (SLE), all of which are characterized by chronic inflammation, tissue destruction and target organ malfunction. Although strong evidence links most autoimmune diseases to specific genes, considerable controversy prevails regarding the role of regulatory T-cell populations in the disease process. These cells are now also believed to play a key role in mediating transplantation tolerance and inhibiting the induction of tumor immunity. Though the concept of therapeutic immune regulation aimed at treating autoimmune pathology has been validated in many animal models, the development of strategies for the treatment of human autoimmune disorders remains in its infancy. The main obstacles to this include the conflicting findings of different model systems, as well as the contrasting functions of regulatory T-cells and cytokines involved in the development of such disorders. This review examines the role of regulatory T-cells in the pathogenesis of autoimmunity and describes the therapeutic potential of these cells for the prevention of immune-mediated pathologies in the future. Although much remains to be learned about such pathologies, a clearer understanding of the mechanisms by which regulatory T-cells function will undoubtedly lead to exciting new possibilities for immunotherapeutics.

  20. Antigen-Specific Polyclonal Cytotoxic T Lymphocytes Induced by Fusions of Dendritic Cells and Tumor Cells

    Directory of Open Access Journals (Sweden)

    Shigeo Koido

    2010-01-01

    Full Text Available The aim of cancer vaccines is induction of tumor-specific cytotoxic T lymphocytes (CTLs that can reduce the tumor mass. Dendritic cells (DCs are potent antigen-presenting cells and play a central role in the initiation and regulation of primary immune responses. Thus, DCs-based vaccination represents a potentially powerful strategy for induction of antigen-specific CTLs. Fusions of DCs and whole tumor cells represent an alternative approach to deliver, process, and subsequently present a broad spectrum of antigens, including those known and unidentified, in the context of costimulatory molecules. Once DCs/tumor fusions have been infused back into patient, they migrate to secondary lymphoid organs, where the generation of antigen-specific polyclonal CTL responses occurs. We will discuss perspectives for future development of DCs/tumor fusions for CTL induction.

  1. Oral chronic graft-versus-host disease: analysis of dendritic cells subpopulations*

    Science.gov (United States)

    Botari, Clara Marino Espricigo; Nunes, Adauto José Ferreira; de Souza, Mair Pedro; Orti-Raduan, Érica Sinara Lenharo; Salvio, Ana Gabriela

    2014-01-01

    The graft-versus-host disease is the major cause of morbidity and mortality in patients who have undergone hematopoietic stem cell transplantation. Aiming at contributing to the understanding of the role of myeloid and plasmacytoid dendritic cells, and natural killer cells in chronic graft-versus-host disease, we examined biopsies of jugal mucosa of 26 patients with acute myeloid leukemia who had undergone allogenic hematopoietic stem cell transplantation. Half of these patients developed oral chronic graft-versus-host disease. Microscopic sections were immunohistochemically stained for anti-CD1a, anti-CD123 and anti-CD56. We calculated the number of immunostained cells in the corium per square millimeter and applied the Mann-Whitney test. Results showed a statistically significant increase of myeloid dendritic cells (CD1a+; p=0,02) and natural killer cells (CD56; p=0,04) in patients with oral chronic graft-versus-host disease. CD123 immunostaining showed no statistical difference between groups. It was concluded that myeloid dendritic cells and natural killer cells participate in the development of oral chronic graft-versus-host disease. PMID:25054751

  2. Oral chronic graft-versus-host disease: analysis of dendritic cells subpopulations.

    Science.gov (United States)

    Botari, Clara Marino Espricigo; Nunes, Adauto José Ferreira; Souza, Mair Pedro de; Orti-Raduan, Erica Sinara Lenharo; Salvio, Ana Gabriela

    2014-01-01

    The graft-versus-host disease is the major cause of morbidity and mortality in patients who have undergone hematopoietic stem cell transplantation. Aiming at contributing to the understanding of the role of myeloid and plasmacytoid dendritic cells, and natural killer cells in chronic graft-versus-host disease, we examined biopsies of jugal mucosa of 26 patients with acute myeloid leukemia who had undergone allogenic hematopoietic stem cell transplantation. Half of these patients developed oral chronic graft-versus-host disease. Microscopic sections were immunohistochemically stained for anti-CD1a, anti-CD123 and anti-CD56. We calculated the number of immunostained cells in the corium per square millimeter and applied the Mann-Whitney test. Results showed a statistically significant increase of myeloid dendritic cells (CD1a+; p=0,02) and natural killer cells (CD56; p=0,04) in patients with oral chronic graft-versus-host disease. CD123 immunostaining showed no statistical difference between groups. It was concluded that myeloid dendritic cells and natural killer cells participate in the development of oral chronic graft-versus-host disease.

  3. Ebola virus: the role of macrophages and dendritic cells in the pathogenesis of Ebola hemorrhagic fever.

    Science.gov (United States)

    Bray, Mike; Geisbert, Thomas W

    2005-08-01

    Ebola hemorrhagic fever is a severe viral infection characterized by fever, shock and coagulation defects. Recent studies in macaques show that major features of illness are caused by effects of viral replication on macrophages and dendritic cells. Infected macrophages produce proinflammatory cytokines, chemokines and tissue factor, attracting additional target cells and inducing vasodilatation, increased vascular permeability and disseminated intravascular coagulation. However, they cannot restrict viral replication, possibly because of suppression of interferon responses. Infected dendritic cells also secrete proinflammatory mediators, but cannot initiate antigen-specific responses. In consequence, virus disseminates to these and other cell types throughout the body, causing multifocal necrosis and a syndrome resembling septic shock. Massive "bystander" apoptosis of natural killer and T cells further impairs immunity. These findings suggest that modifying host responses would be an effective therapeutic strategy, and treatment of infected macaques with a tissue-factor inhibitor reduced both inflammation and viral replication and improved survival.

  4. A Rare Case of Retroperitoneal Follicular Dendritic Cell Sarcoma Identified by 99mTc-HYNIC-TOC SPECT/CT.

    Science.gov (United States)

    Li, Yi; Xu, Xiaoping; Xu, Junyan; Huang, Dan

    2018-05-31

    Follicular dendritic cell sarcoma is a very rare neoplasm, which is not lymphoma, but originates from a type of immune cells called follicular dendritic cells. We presented a 37-year-old woman who has suffered from obstructive jaundice, weight loss and right upper abdominal pain for 2 months. The contrast CT revealed masses located in the region of pancreatic head and lots of enlarged retroperitoneal lymph nodes, both of which were enhanced on the artery phase of CT images. Meanwhile, Tc-HYNIC-TOC SPECT/CT revealed high activity in the corresponding lesions. After biopsy, the masses were pathologically confirmed as retroperitoneal follicular dendritic cell sarcoma.

  5. Multiple dendritic cell populations activate CD4+ T cells after viral stimulation.

    Directory of Open Access Journals (Sweden)

    Adele M Mount

    2008-02-01

    Full Text Available Dendritic cells (DC are a heterogeneous cell population that bridge the innate and adaptive immune systems. CD8alpha DC play a prominent, and sometimes exclusive, role in driving amplification of CD8(+ T cells during a viral infection. Whether this reliance on a single subset of DC also applies for CD4(+ T cell activation is unknown. We used a direct ex vivo antigen presentation assay to probe the capacity of flow cytometrically purified DC populations to drive amplification of CD4(+ and CD8(+ T cells following infection with influenza virus by different routes. This study examined the contributions of non-CD8alpha DC populations in the amplification of CD8(+ and CD4(+ T cells in cutaneous and systemic influenza viral infections. We confirmed that in vivo, effective immune responses for CD8(+ T cells are dominated by presentation of antigen by CD8alpha DC but can involve non-CD8alpha DC. In contrast, CD4(+ T cell responses relied more heavily on the contributions of dermal DC migrating from peripheral lymphoid tissues following cutaneous infection, and CD4 DC in the spleen after systemic infection. CD4(+ T cell priming by DC subsets that is dependent upon the route of administration raises the possibility that vaccination approaches could be tailored to prime helper T cell immunity.

  6. A phagocytotic inducer from herbal constituent, pentagalloylglucose enhances lipoplex-mediated gene transfection in dendritic cells.

    Science.gov (United States)

    Kato, Shinichiro; Koizumi, Keiichi; Yamada, Miyuki; Inujima, Akiko; Takeno, Nobuhiro; Nakanishi, Tsuyoshi; Sakurai, Hiroaki; Nakagawa, Shinsaku; Saiki, Ikuo

    2010-01-01

    Antigen-presenting cells are key vehicles for delivering antigens in tumor immunotherapy, and the most potent of them are dendritic cells (DCs). Recent studies have demonstrated the usefulness of DCs genetically modified by lipofection in tumor immune therapy, although sufficient gene transduction into DCs is quite difficult. Here, we show that Paeoniae radix, herbal medicine, and the constituent, 1,2,3,4,6-penta-O-galloyl-β-D-glucose (PGG), have an attractive function to enhance phagocytosis in murine dendritic cell lines, DC2.4 cells. In particular, PGG in combination with lipofectin (LPF) enhanced phagocytic activity. Furthermore, PGG enhanced lipofection efficacy in DC2.4 cells, but not in colorectal carcinoma cell lines, Colon26. In other words, PGG synergistically enhanced the effect of lipofectin-dependent phagocytosis on phagocytic cells. Hence, according to our data, PGG could be an effective aid in lipofection using dendritic cells. Furthermore, these findings provide an expectation that constituents from herbal plant enhance lipofection efficacy.

  7. In vivo dendritic cell depletion reduces breeding efficiency, affecting implantation and early placental development in mice.

    Science.gov (United States)

    Krey, Gesa; Frank, Pierre; Shaikly, Valerie; Barrientos, Gabriela; Cordo-Russo, Rosalia; Ringel, Frauke; Moschansky, Petra; Chernukhin, Igor V; Metodiev, Metodi; Fernández, Nelson; Klapp, Burghard F; Arck, Petra C; Blois, Sandra M

    2008-09-01

    Implantation of mammalian embryos into their mother's uterus ensures optimal nourishment and protection throughout development. Complex molecular interactions characterize the implantation process, and an optimal synchronization of the components of this embryo-maternal dialogue is crucial for a successful reproductive outcome. In the present study, we investigated the role of dendritic cells (DC) during implantation process using a transgenic mouse system (DTRtg) that allows transient depletion of CD11c+ cells in vivo through administration of diphtheria toxin. We observed that DC depletion impairs the implantation process, resulting in a reduced breeding efficiency. Furthermore, the maturity of uterine natural killer cells at dendritic cell knockout (DCKO) implantation sites was affected as well; as demonstrated by decreased perforin expression and reduced numbers of periodic-acid-Schiff (PAS)-positive cells. This was accompanied by disarrangements in decidual vascular development. In the present study, we were also able to identify a novel DC-dependent protein, phosphatidylinositol transfer protein beta (PITPbeta), involved in implantation and trophoblast development using a proteomic approach. Indeed, DCKO mice exhibited substantial anomalies in placental development, including hypocellularity of the spongiotrophoblast and labyrinthine layers and reduced numbers of trophoblast giant cells. Giant cells also down-regulated their expression of two characteristic markers of trophoblast differentiation, placental lactogen 1 and proliferin. In view of these findings, dendritic cells emerge as possible modulators in the orchestration of events leading to the establishment and maintenance of pregnancy.

  8. Genomic Programming of Human Neonatal Dendritic Cells in Congenital Systemic and In Vitro Cytomegalovirus Infection Reveal Plastic and Robust Immune Pathway Biology Responses

    Directory of Open Access Journals (Sweden)

    Widad Dantoft

    2017-09-01

    Full Text Available Neonates and especially premature infants are highly susceptible to infection but still can have a remarkable resilience that is poorly understood. The view that neonates have an incomplete or deficient immune system is changing. Human neonatal studies are challenging, and elucidating host protective responses and underlying cognate pathway biology, in the context of viral infection in early life, remains to be fully explored. In both resource rich and poor settings, human cytomegalovirus (HCMV is the most common cause of congenital infection. By using unbiased systems analyses of transcriptomic resources for HCMV neonatal infection, we find the systemic response of a preterm congenital HCMV infection, involves a focused IFN regulatory response associated with dendritic cells. Further analysis of transcriptional-programming of neonatal dendritic cells in response to HCMV infection in culture revealed an early dominant IFN-chemokine regulatory subnetworks, and at later times the plasticity of pathways implicated in cell-cycle control and lipid metabolism. Further, we identify previously unknown suppressed networks associated with infection, including a select group of GPCRs. Functional siRNA viral growth screen targeting 516-GPCRs and subsequent validation identified novel GPCR-dependent antiviral (ADORA1 and proviral (GPR146, RGS16, PTAFR, SCTR, GPR84, GPR85, NMUR2, FZ10, RDS, CCL17, and SORT1 roles. By contrast a gene family cluster of protocadherins is significantly differentially induced in neonatal cells, suggestive of possible immunomodulatory roles. Unexpectedly, programming responses of adult and neonatal dendritic cells, upon HCMV infection, demonstrated comparable quantitative and qualitative responses showing that functionally, neonatal dendritic cell are not overly compromised. However, a delay in responses of neonatal cells for IFN subnetworks in comparison with adult-derived cells are notable, suggestive of subtle plasticity

  9. Genomic Programming of Human Neonatal Dendritic Cells in Congenital Systemic and In Vitro Cytomegalovirus Infection Reveal Plastic and Robust Immune Pathway Biology Responses.

    Science.gov (United States)

    Dantoft, Widad; Martínez-Vicente, Pablo; Jafali, James; Pérez-Martínez, Lara; Martin, Kim; Kotzamanis, Konstantinos; Craigon, Marie; Auer, Manfred; Young, Neil T; Walsh, Paul; Marchant, Arnaud; Angulo, Ana; Forster, Thorsten; Ghazal, Peter

    2017-01-01

    Neonates and especially premature infants are highly susceptible to infection but still can have a remarkable resilience that is poorly understood. The view that neonates have an incomplete or deficient immune system is changing. Human neonatal studies are challenging, and elucidating host protective responses and underlying cognate pathway biology, in the context of viral infection in early life, remains to be fully explored. In both resource rich and poor settings, human cytomegalovirus (HCMV) is the most common cause of congenital infection. By using unbiased systems analyses of transcriptomic resources for HCMV neonatal infection, we find the systemic response of a preterm congenital HCMV infection, involves a focused IFN regulatory response associated with dendritic cells. Further analysis of transcriptional-programming of neonatal dendritic cells in response to HCMV infection in culture revealed an early dominant IFN-chemokine regulatory subnetworks, and at later times the plasticity of pathways implicated in cell-cycle control and lipid metabolism. Further, we identify previously unknown suppressed networks associated with infection, including a select group of GPCRs. Functional siRNA viral growth screen targeting 516-GPCRs and subsequent validation identified novel GPCR-dependent antiviral (ADORA1) and proviral (GPR146, RGS16, PTAFR, SCTR, GPR84, GPR85, NMUR2, FZ10, RDS, CCL17, and SORT1) roles. By contrast a gene family cluster of protocadherins is significantly differentially induced in neonatal cells, suggestive of possible immunomodulatory roles. Unexpectedly, programming responses of adult and neonatal dendritic cells, upon HCMV infection, demonstrated comparable quantitative and qualitative responses showing that functionally, neonatal dendritic cell are not overly compromised. However, a delay in responses of neonatal cells for IFN subnetworks in comparison with adult-derived cells are notable, suggestive of subtle plasticity differences. These

  10. Environment and T regulatory cells in allergy.

    Science.gov (United States)

    Braga, M; Schiavone, C; Di Gioacchino, G; De Angelis, I; Cavallucci, E; Lazzarin, F; Petrarca, C; Di Gioacchino, M

    2012-04-15

    The central role of T regulatory cells in the responses against harmless environmental antigens has been confirmed by many studies. Impaired T regulatory cell function is implicated in many pathological conditions, particularly allergic diseases. The "hygiene hypothesis" suggests that infections and infestations may play a protective role for allergy, whereas environmental pollutants favor the development of allergic diseases. Developing countries suffer from a variety of infections and are also facing an increasing diffusion of environmental pollutants. In these countries allergies increase in relation to the spreading use of xenobiotics (pesticides, herbicides, pollution, etc.) with a rate similar to those of developed countries, overcoming the protective effects of infections. We review here the main mechanisms of non-self tolerance, with particular regard to relations between T regulatory cell activity, infections and infestations such as helminthiasis, and exposure to environmental xenobiotics with relevant diffusion in developing countries. Copyright © 2010 Elsevier B.V. All rights reserved.

  11. Regulatory T Cells in Human Ovarian Cancer

    Directory of Open Access Journals (Sweden)

    Dong-Jun Peng

    2012-01-01

    Full Text Available Multiple layers of suppressive components including regulatory T (TReg cells, suppressive antigen-presenting cells, and inhibitory cytokines form suppressive networks in the ovarian cancer microenvironment. It has been demonstrated that as a major suppressive element, TReg cells infiltrate tumor, interact with several types of immune cells, and mediate immune suppression through different molecular and cellular mechanisms. In this paper, we focus on human ovarian cancer and will discuss the nature of TReg cells including their subsets, trafficking, expansion, and function. We will briefly review the development of manipulation of TReg cells in preclinical and clinical settings.

  12. IRF8 Transcription-Factor-Dependent Classical Dendritic Cells Are Essential for Intestinal T Cell Homeostasis.

    Science.gov (United States)

    Luda, Katarzyna M; Joeris, Thorsten; Persson, Emma K; Rivollier, Aymeric; Demiri, Mimoza; Sitnik, Katarzyna M; Pool, Lieneke; Holm, Jacob B; Melo-Gonzalez, Felipe; Richter, Lisa; Lambrecht, Bart N; Kristiansen, Karsten; Travis, Mark A; Svensson-Frej, Marcus; Kotarsky, Knut; Agace, William W

    2016-04-19

    The role of dendritic cells (DCs) in intestinal immune homeostasis remains incompletely defined. Here we show that mice lacking IRF8 transcription-factor-dependent DCs had reduced numbers of T cells in the small intestine (SI), but not large intestine (LI), including an almost complete absence of SI CD8αβ(+) and CD4(+)CD8αα(+) T cells; the latter requiring β8 integrin expression by migratory IRF8 dependent CD103(+)CD11b(-) DCs. SI homing receptor induction was impaired during T cell priming in mesenteric lymph nodes (MLN), which correlated with a reduction in aldehyde dehydrogenase activity by SI-derived MLN DCs, and inefficient T cell localization to the SI. These mice also lacked intestinal T helper 1 (Th1) cells, and failed to support Th1 cell differentiation in MLN and mount Th1 cell responses to Trichuris muris infection. Collectively these results highlight multiple non-redundant roles for IRF8 dependent DCs in the maintenance of intestinal T cell homeostasis. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Biology and function of adipose tissue macrophages, dendritic cells and B cells.

    Science.gov (United States)

    Ivanov, Stoyan; Merlin, Johanna; Lee, Man Kit Sam; Murphy, Andrew J; Guinamard, Rodolphe R

    2018-04-01

    The increasing incidence of obesity and its socio-economical impact is a global health issue due to its associated co-morbidities, namely diabetes and cardiovascular disease [1-5]. Obesity is characterized by an increase in adipose tissue, which promotes the recruitment of immune cells resulting in low-grade inflammation and dysfunctional metabolism. Macrophages are the most abundant immune cells in the adipose tissue of mice and humans. The adipose tissue also contains other myeloid cells (dendritic cells (DC) and neutrophils) and to a lesser extent lymphocyte populations, including T cells, B cells, Natural Killer (NK) and Natural Killer T (NKT) cells. While the majority of studies have linked adipose tissue macrophages (ATM) to the development of low-grade inflammation and co-morbidities associated with obesity, emerging evidence suggests for a role of other immune cells within the adipose tissue that may act in part by supporting macrophage homeostasis. In this review, we summarize the current knowledge of the functions ATMs, DCs and B cells possess during steady-state and obesity. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. [Regulatory T cells inhibit proliferation of mouse lymphoma cell line EL4 in vitro].

    Science.gov (United States)

    Zhang, Chen; Kong, Yan; Guo, Jun; Ying, Zhi-Tao; Yuan, Zhi-Hong; Zhang, Yun-Tao; Zheng, Wen; Song, Yu-Qin; Li, Ping-Ping; Zhu, Jun

    2010-10-01

    This study was aimed to investigate the effect of regulatory T (Treg) cells on the T cell lymphoma EL4 cells and its mechanism in vitro. C57BL/6 mouse Treg cells were isolated by magnetic cell sorting (MACS). The purity of Treg cells and their expression of Foxp3 were identified by flow cytometry (FCM) and PT-PCR respectively. The suppression of Treg cells on EL4 cells was detected by 3H-TdR method. At the same time, enzyme-linked immunosorbent assay (ELISA) was used to detect the secretion of cytokine TGF-β1 and IL-10. The results showed that CD4+CD25+ T cells could be successfully isolated by MACS with the purity reaching 94.52% and the expression of Foxp3 reaching 84.72%. After sorting, the expression of Foxp3 mRNA could be detected by RT-PCR. 3H-TdR assay confirmed that regulatory T cells could suppress the proliferation of EL4 cells with or without antigen presenting cells (APC) or dendritic cells (DC), APC or DC might effectively enhance the suppression. In addition, DC alone also suppressed the proliferation. TGF-β1 and IL-10 could be detected in the supernatant by ELISA. It is concluded that the Treg cells can obviously suppress the proliferation of T cell lymphoma cells in vitro, APC or DC can enhance this suppressive effect, while the DC alone also can suppress the proliferation of EL4 cells, the TGF-β1 and IL-10 cytokine pathway may be one of the mechanisms of suppression.

  15. Targeting CD4(+) T-Helper Cells Improves the Induction of Antitumor Responses in Dendritic Cell-Based Vaccination

    NARCIS (Netherlands)

    Aarntzen, Erik H. J. G.; de Vries, I. Jolanda M.; Lesterhuis, W. Joost; Schuurhuis, Danita; Jacobs, Joannes F. M.; Bol, Kalijn; Schreibelt, Gerty; Mus, Roel; de Wilt, Johannes H. W.; Haanen, John B. A. G.; Schadendorf, Dirk; Croockewit, Alexandra; Blokx, Willeke A. M.; van Rossum, Michelle M.; Kwok, William W.; Adema, Gosse J.; Punt, Cornelis J. A.; Figdor, Carl G.

    2013-01-01

    To evaluate the relevance of directing antigen-specific CD4(+) T helper cells as part of effective anticancer immunotherapy, we investigated the immunologic and clinical responses to vaccination with dendritic cells (DC) pulsed with either MHC class I (MHC-I)-restricted epitopes alone or both MHC

  16. Dendritic Cell Stimulation by IFN-β Alters T Cell Function via Modulation of Cytokine Secretion in Diabetes Type 1

    Directory of Open Access Journals (Sweden)

    Abediankenari Saeid

    2009-10-01

    Full Text Available During antigen capture and processing, mature dendritic cells (DC express large amounts of peptide-MHC complexes and accessory molecules on their surface. We investigated the role of IFN-β in induction HLA-G expression on the monocyte derived DC and cytokine profile in diabetes type 1. We accomplished secretary pattern and total cytokine production of the Th1 cytokine (IL-2, γIFN and Th2 cytokines (IL-4, IL-10 before and after mixed leukocyte reaction (MLR of 30 diabetic patients and 30 normal subjects.   In this study a significant increase of IL-10 and γIFN reduction after IFN-β Therapy in culture in presence of HLA-G bearing DC as compared to control were seen. It is seen that dendritic cell causes IL-10 production of T cell in vitro that reduce T cell activation from diabetes patients and normal subjects resulted to the production and expression of HLA-G on these cells from both groups. Using mixed leukocyte reaction, it was found that IFN-β-treated dendritic cell mediated the inhibition of autologous T cell activation via IL-10 production and level of HLA-G on dendritic cell may be correlated to disease activity in diabetes patients and it could also serve as a useful marker for disease progress and treatment.

  17. 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

  18. MUC1 in human milk blocks transmission of human immunodeficiency virus from dendritic cells to T cells

    NARCIS (Netherlands)

    Saeland, E.; Jong, de M.A.W.P.; Nabatov, A.; Kalay, H.; Kooijk, van Y.; Geijtenbeek, T.B.H.

    2009-01-01

    Mother-to-child transmission of human immunodeficiency virus-1 (HIV-1) occurs frequently via breast-feeding. HIV-1 targets DC-SIGN+ dendritic cells (DCs) in mucosal areas that allow efficient transmission of the virus to T cells. Here, we demonstrate that the epithelial mucin MUC1, abundant in milk,

  19. Macrophages are required for dendritic cell uptake of respiratory syncytial virus from an infected epithelium.

    Science.gov (United States)

    Ugonna, Kelechi; Bingle, Colin D; Plant, Karen; Wilson, Kirsty; Everard, Mark L

    2014-01-01

    We have previously shown that the respiratory syncytial virus [RSV] can productively infect monocyte derived dendritic cells [MoDC] and remain dormant within the same cells for prolonged periods. It is therefore possible that infected dendritic cells act as a reservoir within the airways of individuals between annual epidemics. In the present study we explored the possibility that sub-epithelial DCs can be infected with RSV from differentiated bronchial epithelium and that in turn RSV from DCs can infect the epithelium. A dual co-culture model was established in which a differentiated primary airway epithelium on an Air Liquid Interface (ALI) was cultured on a transwell insert and MoDCs were subsequently added to the basolateral membrane of the insert. Further experiments were undertaken using a triple co-culture model in which in which macrophages were added to the apical surface of the differentiated epithelium. A modified RSV [rr-RSV] expressing a red fluorescent protein marker of replication was used to infect either the MoDCs or the differentiated epithelium and infection of the reciprocal cell type was assessed using confocal microscopy. Our data shows that primary epithelium became infected when rr-RSV infected MoDCs were introduced onto the basal surface of the transwell insert. MoDCs located beneath the epithelium did not become infected with virus from infected epithelial cells in the dual co-culture model. However when macrophages were present on the apical surface of the primary epithelium infection of the basal MoDCs occurred. Our data suggests that RSV infected dendritic cells readily transmit infection to epithelial cells even when they are located beneath the basal layer. However macrophages appear to be necessary for the transmission of infection from epithelial cells to basal dendritic cells.

  20. Cross-talk between cd1d-restricted nkt cells and γδ cells in t regulatory cell response

    Directory of Open Access Journals (Sweden)

    Huber Sally A

    2011-01-01

    Full Text Available Abstract CD1d is a non-classical major histocompatibility class 1-like molecule which primarily presents either microbial or endogenous glycolipid antigens to T cells involved in innate immunity. Natural killer T (NKT cells and a subpopulation of γδ T cells expressing the Vγ4 T cell receptor (TCR recognize CD1d. NKT and Vγ4 T cells function in the innate immune response via rapid activation subsequent to infection and secrete large quantities of cytokines that both help control infection and modulate the developing adaptive immune response. T regulatory cells represent one cell population impacted by both NKT and Vγ4 T cells. This review discusses the evidence that NKT cells promote T regulatory cell activation both through direct interaction of NKT cell and dendritic cells and through NKT cell secretion of large amounts of TGFβ, IL-10 and IL-2. Recent studies have shown that CD1d-restricted Vγ4 T cells, in contrast to NKT cells, selectively kill T regulatory cells through a caspase-dependent mechanism. Vγ4 T cell elimination of the T regulatory cell population allows activation of autoimmune CD8+ effector cells leading to severe cardiac injury in a coxsackievirus B3 (CVB3 myocarditis model in mice. CD1d-restricted immunity can therefore lead to either immunosuppression or autoimmunity depending upon the type of innate effector dominating during the infection.

  1. Dendritic cells and skin sensitization: Biological roles and uses in hazard identification

    International Nuclear Information System (INIS)

    Ryan, Cindy A.; Kimber, Ian; Basketter, David A.; Pallardy, Marc; Gildea, Lucy A.; Gerberick, G. Frank

    2007-01-01

    Recent advances have been made in our understanding of the roles played by cutaneous dendritic cells (DCs) in the induction of contact allergy. A number of associated changes in epidermal Langerhans cell phenotype and function required for effective skin sensitization are providing the foundations for the development of cellular assays (using DC and DC-like cells) for skin sensitization hazard identification. These alternative approaches to the identification and characterization of skin sensitizing chemicals were the focus of a Workshop entitled 'Dendritic Cells and Skin Sensitization: Biological Roles and Uses in Hazard Identification' that was given at the annual Society of Toxicology meeting held March 6-9, 2006 in San Diego, California. This paper reports information that was presented during the Workshop

  2. Generation of blood-derived dendritic cells in dogs with oral malignant melanoma.

    Science.gov (United States)

    Catchpole, B; Stell, A J; Dobson, J M

    2002-01-01

    Advances in treatment of human melanoma indicate that immunotherapy, particularly dendritic cell (DC) immunization, may prove useful. The aim of this study was to investigate whether blood-derived DCs could be generated from canine melanoma patients. Peripheral blood mononuclear cells were isolated from three such dogs and cultured with recombinant canine granulocyte-macrophage colony stimulating factor (GM-CSF), canine interleukin 4 and human Flt3-ligand for 7 days. The resulting cells demonstrated a typical dendritic morphology, and were enriched for cells expressing CD1a, CD11c and MHC II by flow cytometric analysis. Thus, canine blood-derived DCs can be generated in vitro and DC immunization should be feasible in dogs. Copyright Harcourt Publishers Ltd.

  3. Impact of aging on antigen presentation cell function of dendritic cells.

    Science.gov (United States)

    Wong, Christine; Goldstein, Daniel R

    2013-08-01

    Older people exhibit increased mortality to infections and cancer as compared to younger people, indicating that aging impairs immunity. Dendritic cells (DCs) are key for bridging the innate and adaptive arms of the immune system by priming antigen specific T cells. Discerning how aging impacts DC function to initiate adaptive immune responses is of great biomedical importance as this could lead to the development of novel therapeutics to enhance immunity with aging. This review details reports indicating that aging impairs the antigen presenting function of DCs but highlights other studies indicating preserved DC function with aging. How aging impacts antigen presentation by DCs is complex and without a clear unifying biological underpinning. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Cell-Intrinsic Glycogen Metabolism Supports Early Glycolytic Reprogramming Required for Dendritic Cell Immune Responses.

    Science.gov (United States)

    Thwe, Phyu M; Pelgrom, Leonard; Cooper, Rachel; Beauchamp, Saritha; Reisz, Julie A; D'Alessandro, Angelo; Everts, Bart; Amiel, Eyal

    2017-09-05

    Dendritic cell (DC) activation by Toll-like receptor (TLR) agonists causes rapid glycolytic reprogramming that is required to meet the metabolic demands of their immune activation. Recent efforts in the field have identified an important role for extracellular glucose sourcing to support DC activation. However, the contributions of intracellular glucose stores to these processes have not been well characterized. We demonstrate that DCs possess intracellular glycogen stores and that cell-intrinsic glycogen metabolism supports the early effector functions of TLR-activated DCs. Inhibition of glycogenolysis significantly attenuates TLR-mediated DC maturation and impairs their ability to initiate lymphocyte activation. We further report that DCs exhibit functional compartmentalization of glucose- and glycogen-derived carbons, where these substrates preferentially contribute to distinct metabolic pathways. This work provides novel insights into nutrient homeostasis in DCs, demonstrating that differential utilization of glycogen and glucose metabolism regulates their optimal immune function. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. 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.

  6. CD8+ Tumor-Infiltrating T Cells Are Trapped in the Tumor-Dendritic Cell Network

    Directory of Open Access Journals (Sweden)

    Alexandre Boissonnas

    2013-01-01

    Full Text Available Chemotherapy enhances the antitumor adaptive immune T cell response, but the immunosuppressive tumor environment often dominates, resulting in cancer relapse. Antigen-presenting cells such as tumor-associated macrophages (TAMs and tumor dendritic cells (TuDCs are the main protagonists of tumor-infiltrating lymphocyte (TIL immuno-suppression. TAMs have been widely investigated and are associated with poor prognosis, but the immuno-suppressive activity of TuDCs is less well understood. We performed two-photon imaging of the tumor tissue to examine the spatiotemporal interactions between TILs and TuDCs after chemotherapy. In a strongly immuno-suppressive murine tumor model, cyclophosphamide-mediated chemotherapy transiently enhanced the antitumor activity of adoptively transferred ovalbumin-specific CD8+ T cell receptor transgenic T cells (OTI but barely affected TuDC compartment within the tumor. Time lapse imaging of living tumor tissue showed that TuDCs are organized as a mesh with dynamic interconnections. Once infiltrated into the tumor parenchyma, OTI T cells make antigen-specific and long-lasting contacts with TuDCs. Extensive analysis of TIL infiltration on histologic section revealed that after chemotherapy the majority of OTI T cells interact with TuDCs and that infiltration is restricted to TuDC-rich areas. We propose that the TuDC network exerts antigen-dependent unproductive retention that trap T cells and limit their antitumor effectiveness.

  7. Dendritic Cell-Induced Th1 and Th17 Cell Differentiation for Cancer Therapy

    Directory of Open Access Journals (Sweden)

    Julia Terhune

    2013-11-01

    Full Text Available The success of cellular immunotherapies against cancer requires the generation of activated CD4+ and CD8+ T-cells. The type of T-cell response generated (e.g., Th1 or Th2 will determine the efficacy of the therapy, and it is generally assumed that a type-1 response is needed for optimal cancer treatment. IL-17 producing T-cells (Th17/Tc17 play an important role in autoimmune diseases, but their function in cancer is more controversial. While some studies have shown a pro-cancerous role for IL-17, other studies have shown an anti-tumor function. The induction of polarized T-cell responses can be regulated by dendritic cells (DCs. DCs are key regulators of the immune system with the ability to affect both innate and adaptive immune responses. These properties have led many researchers to study the use of ex vivo manipulated DCs for the treatment of various diseases, such as cancer and autoimmune diseases. While Th1/Tc1 cells are traditionally used for their potent anti-tumor responses, mounting evidence suggests Th17/Tc17 cells should be utilized by themselves or for the induction of optimal Th1 responses. It is therefore important to understand the factors involved in the induction of both type-1 and type-17 T-cell responses by DCs.

  8. REMOD: a tool for analyzing and remodeling the dendritic architecture of neural cells

    Directory of Open Access Journals (Sweden)

    Panagiotis eBozelos

    2016-01-01

    Full Text Available Dendritic morphology is a key determinant of how individual neurons acquire a unique signal processing profile. The highly branched dendritic structure that originates from the cell body, explores the surrounding 3D space in a fractal-like manner, until it reaches a certain amount of complexity. Its shape undergoes significant alterations under various physiological or neuropathological conditions. Yet, despite the profound effect that these alterations can have on neuronal function, the causal relationship between the two remains largely elusive. The lack of a systematic approach for remodeling neural cells and their dendritic trees is a key limitation that contributes to this problem. Such causal relationships can be inferred via the use of large-scale neuronal models whereby the anatomical plasticity of neurons is accounted for, in order to enhance their biological relevance and hence their predictive performance. To facilitate this effort, we developed a computational tool named REMOD that allows the structural remodeling of any type of virtual neuron. REMOD is written in Python and can be accessed through a dedicated web interface that guides the user through various options to manipulate selected neuronal morphologies. REMOD can also be used to extract meaningful morphology statistics for one or multiple reconstructions, including features such as sholl analysis, total dendritic length and area, path length to the soma, centrifugal branch order, diameter tapering and more. As such, the tool can be used both for the analysis and/or the remodeling of neuronal morphologies of any type.

  9. Perspectives on Regulatory T Cell Therapies.

    Science.gov (United States)

    Probst-Kepper, Michael; Kröger, Andrea; Garritsen, Henk S P; Buer, Jan

    2009-01-01

    Adoptive transfer in animal models clearly indicate an essential role of CD4+ CD25+ FOXP3+ regulatory T (T(reg)) cells in prevention and treatment of autoimmune and graft-versus-host disease. Thus, T(reg) cell therapies and development of drugs that specifically enhance T(reg) cell function and development represent promising tools to establish dominant tolerance. So far, lack of specific markers to differentiate human T(reg) cells from activated CD4+ CD25+ effector T cells, which also express FOXP3 at different levels, hampered such an approach. Recent identification of the orphan receptor glycoprotein-A repetitions predominant (GARP or LRRC32) as T(reg) cell-specific key molecule that dominantly controls FOXP3 via a positive feedback loop opens up new perspectives for molecular and cellular therapies. This brief review focuses on the role of GARP as a safeguard of a complex regulatory network of human T(reg) cells and its implications for regulatory T cell therapies in autoimmunity and graft-versus-host disease.

  10. Immunodetection of myeloid and plasmacytoid dendritic cells in mammary carcinomas of female dogs

    Directory of Open Access Journals (Sweden)

    Mayara C. Rosolem

    2015-11-01

    Full Text Available ABSTRACT: Dendritic cells have attracted great interest from researchers as they may be used as targets of tumor immune evasion mechanisms. The main objective of this study was to evaluate the relationship between the dendritic cells (DCs subpopulation in simple type mammary carcinomas in female dogs. Two groups of samples were used: the control group consisted of 18 samples of mammary tissue without changes and the tumor group with 26 simple type mammary carcinomas. In these groups, we evaluated the immunodetection of immature and mature myeloid DCs, plasmacytoid DCs and MHC-II. In mammary tumor, mature myeloid DCs predominated in the peritumoral region, while immature myeloid DCs and plasmacytoid DCs were evident in the intratumoral region. Immunostaining of MHC-II was visualized in mammary acini (control group, in tumor cells and inflammatory infiltration associated with tumors. The comparison between the control and tumor groups showed a statistically significant difference between immature myeloid DCs, mature myeloid DCs and plasmacytoid DCs. The immunodetection of MHC-II was not significant when comparing the groups. The predominance of immature DCs in the tumor group is possibly related to an inefficient immune response, promoting the development and survival of tumor cells. The presence of plasmacytoid DCs in the same group suggests a worse prognosis for female dogs with mammary tumors. Therefore, the ability of differentiation of canine dendritic cells could be influenced by neoplastic cells and by the tumor microenvironment.

  11. CD301b⁺ dermal dendritic cells drive T helper 2 cell-mediated immunity.

    Science.gov (United States)

    Kumamoto, Yosuke; Linehan, Melissa; Weinstein, Jason S; Laidlaw, Brian J; Craft, Joseph E; Iwasaki, Akiko

    2013-10-17

    Unlike other types of T helper (Th) responses, whether the development of Th2 cells requires instruction from particular subset of dendritic cells (DCs) remains unclear. By using an in vivo depletion approach, we have shown that DCs expressing CD301b were required for the generation of Th2 cells after subcutaneous immunization with ovalbumin (OVA) along with papain or alum. CD301b⁺ DCs are distinct from epidermal or CD207⁺ dermal DCs (DDCs) and were responsible for transporting antigen injected subcutaneously with Th2-type adjuvants. Transient depletion of CD301b⁺ DCs resulted in less effective accumulation and decreased expression of CD69 by polyclonal CD4⁺ T cells in the lymph node. Moreover, despite intact cell division and interferon-γ production, CD301b⁺ DC depletion led to blunted interleukin-4 production by OVA-specific OT-II transgenic CD4⁺ T cells and significantly impaired Th2 cell development upon infection with Nippostrongylus brasiliensis. These results reveal CD301b⁺ DDCs as the key mediators of Th2 immunity. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Dendritic cell, monocyte and T cell activation and response to glatiramer acetate in multiple sclerosis

    DEFF Research Database (Denmark)

    Sellebjerg, F; Hesse, D; Limborg, S

    2012-01-01

    , monocytes and dendritic cells (DC) in relation to disease activity in MS patients treated with GA. Methods: Flow cytometry was used to study the activation of CD4+ T cells and T cell subsets (CD25high and CD26high cells), monocytes and DCs in a cross-sectional study of 39 untreated and 29 GA-treated MS......Background: Treatment with glatiramer acetate (GA) modestly decreases disease activity in multiple sclerosis (MS). The mechanism of action is incompletely understood and differences in the response to treatment between individuals may exist. Objective: To study the activation of CD4+ T cells...... (Bonferroni-corrected p=0.0005). The hazard ratio of relapse was 1.32 (95% confidence interval 1.05–1.64) per 1% increase in CD40+ DCs. Patients treated with GA had fewer CD4+ T cells expressing surface markers associated with T helper type 1 effector responses and more CD4+ T cells expressing surface markers...

  13. A generic RNA-pulsed dendritic cell vaccine strategy for renal cell carcinoma

    Science.gov (United States)

    Geiger, Christiane; Regn, Sybille; Weinzierl, Andreas; Noessner, Elfriede; Schendel, Dolores J

    2005-01-01

    We present a generic dendritic cell (DC) vaccine strategy for patients with renal cell carcinoma (RCC) based on the use of RNA as a source of multiplex tumor-associated antigens (TAAs). Instead of preparing RNA from tumor tissue of each individual RCC patient, we propose to substitute RNA prepared from a well characterized highly immunogenic RCC cell line (RCC-26 tumor cells) as a generic source of TAAs for loading of DCs. We demonstrate here that efficient RNA transfer can be achieved using lipofection of immature DCs, which are subsequently matured with a cytokine cocktail to express high levels of MHC and costimulatory molecules as well as the chemokine receptor CCR7. Neither RNA itself nor the lipid component impacted on the phenotype or the cytokine secretion of mature DCs. Following RNA loading, DCs derived from HLA-A2-positive donors were able to activate effector-memory cytotoxic T lymphocytes (CTLs) specific for a TAA ligand expressed by the RCC-26 cell line. CTL responses to RNA-loaded DCs reached levels comparable to those stimulated directly by the RCC-26 tumor cells. Furthermore, DCs expressing tumor cell RNA primed naïve T cells, yielding T cell lines with cytotoxicity and cytokine secretion after contact with RCC tumor cells. RCC-26 cell lines are available as good manufacturing practice (GMP)-certified reagents enabling this source of RNA to be easily standardized and adapted for clinical testing. In addition, well defined immune monitoring tools, including the use of RNA expressing B cell lines, are available. Thus, this DC vaccine strategy can be directly compared with an ongoing gene therapy trial using genetically-engineered variants of the RCC-26 cell line as vaccines for RCC patients with metastatic disease. PMID:16045799

  14. A generic RNA-pulsed dendritic cell vaccine strategy for renal cell carcinoma

    Directory of Open Access Journals (Sweden)

    Noessner Elfriede

    2005-07-01

    Full Text Available Abstract We present a generic dendritic cell (DC vaccine strategy for patients with renal cell carcinoma (RCC based on the use of RNA as a source of multiplex tumor-associated antigens (TAAs. Instead of preparing RNA from tumor tissue of each individual RCC patient, we propose to substitute RNA prepared from a well characterized highly immunogenic RCC cell line (RCC-26 tumor cells as a generic source of TAAs for loading of DCs. We demonstrate here that efficient RNA transfer can be achieved using lipofection of immature DCs, which are subsequently matured with a cytokine cocktail to express high levels of MHC and costimulatory molecules as well as the chemokine receptor CCR7. Neither RNA itself nor the lipid component impacted on the phenotype or the cytokine secretion of mature DCs. Following RNA loading, DCs derived from HLA-A2-positive donors were able to activate effector-memory cytotoxic T lymphocytes (CTLs specific for a TAA ligand expressed by the RCC-26 cell line. CTL responses to RNA-loaded DCs reached levels comparable to those stimulated directly by the RCC-26 tumor cells. Furthermore, DCs expressing tumor cell RNA primed naïve T cells, yielding T cell lines with cytotoxicity and cytokine secretion after contact with RCC tumor cells. RCC-26 cell lines are available as good manufacturing practice (GMP-certified reagents enabling this source of RNA to be easily standardized and adapted for clinical testing. In addition, well defined immune monitoring tools, including the use of RNA expressing B cell lines, are available. Thus, this DC vaccine strategy can be directly compared with an ongoing gene therapy trial using genetically-engineered variants of the RCC-26 cell line as vaccines for RCC patients with metastatic disease.

  15. Mechanism of immune tolerance induced by donor derived immature dendritic cells in rat high-risk corneal transplantation

    Directory of Open Access Journals (Sweden)

    Xu-Dong Zhao

    2013-06-01

    Full Text Available AIM: To study the role of immature dendritic cells (imDCs on immune tolerance in rat penetrating keratoplasty (PKP in high-risk eyes and to investigate the mechanism of immune hyporesponsiveness induced by donor-derived imDCs. METHODS: Seventy-five SD rats (recipient and 39 Wistar rats (donor were randomly divided into 3 groups: control, imDC and mature dendritic cell (mDC group respectively. Using a model of orthotopic corneal transplantation in which allografts were placed in neovascularized high-risk eyes of recipient rat. Corneal neovascularization was induced by alkaline burn in the central cornea of recipient rat. Recipients in imDC group or mDC group were injected donor bone marrow-derived imDCs or mDCs of 1×106 respectively 1 week before corneal transplantation via tail vein. Control rat received the same volume of PBS. In each group, 16 recipients were kept for determination of survival time and other 9 recipients were executed on day 3, 7 and 14 after transplantation. Cornea was harvested for hematoxylin-eosin staining and acute rejection evaluation, Western blot was used to detect the expression level of Foxp3. RESULTS: The mean survival time of imDC group was significantly longer than that of control and mDC groups (all P<0.05. The expression level of Foxp3 on CD4+CD25+T cells of imDC group (2.24±0.18 was significantly higher than that in the control (1.68±0.09 and mDC groups (1.46±0.13 (all P<0.05. CONCLUSION: Donor-derived imDC is an effective treatment in inducing immune hyporesponsiveness in rat PKP. The mechanism of immune tolerance induced by imDC might be inhibit T lymphocytes responsiveness by regulatory T cells.

  16. Regulatory T cells and B cells: implication on autoimmune diseases

    OpenAIRE

    Wang, Ping; Zheng, Song Guo

    2013-01-01

    The regulatory T (Treg) cells play an important role in the maintenance of homeostasis and the prevention of autoimmune diseases. Although most studies are focusing on the role of Treg cells in T cells and T cells-mediated diseases, these cells also directly affect B cells and other non-T cells. This manuscript updates the role of Treg cells on the B cells and B cell-mediated diseases. In addition, the mechanisms whereby Treg cells suppress B cell responses have been discussed.

  17. Suppressive effects of primed eosinophils on single epicutaneous sensitization through regulation of dermal dendritic cells.

    Science.gov (United States)

    Lin, Jing-Yi; Ta, Yng-Cun; Liu, I-Lin; Chen, Hsi-Wen; Wang, Li-Fang

    2016-07-01

    Eosinophils are multifunctional innate immune cells involved in many aspects of innate and adaptive immunity. Epicutaneous sensitization with protein allergen is an important sensitization route for atopic dermatitis. In this study, using a murine single protein-patch model, we show that eosinophils of a primed status accumulate in draining lymph nodes following single epicutaneous sensitization. Further, depletion of eosinophils results in enhancement of the induced Th1/Th2 immune responses, whereas IL-5-induced hypereosinophilia suppresses these responses. Mechanistically, primed eosinophils cause a reduction in the numbers and activation status of dermal dendritic cells in draining lymph nodes. Collectively, these results demonstrate that primed eosinophils exert suppressive effects on single epicutaneous sensitization through regulation of dermal dendritic cells. Thus, these findings highlight the critical roles of eosinophils in the pathogenesis of atopic dermatitis with important clinical implications for the prevention of allergen sensitization. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Neisseria meningitidis expressing lgtB lipopolysaccharide targets DC-SIGN and modulates dendritic cell function.

    Science.gov (United States)

    Steeghs, Liana; van Vliet, Sandra J; Uronen-Hansson, Heli; van Mourik, Andries; Engering, Anneke; Sanchez-Hernandez, Martha; Klein, Nigel; Callard, Robin; van Putten, Jos P M; van der Ley, Peter; van Kooyk, Yvette; van de Winkel, Jan G J

    2006-02-01

    Neisseria meningitidis lipopolysaccharide (LPS) has been identified as a major determinant of dendritic cell (DC) function. Here we report that one of a series of meningococcal mutants with defined truncations in the lacto-N-neotetraose outer core of the LPS exhibited unique strong adhesion and internalization properties towards DC. These properties were mediated by interaction of the GlcNAc(beta1-3)-Gal(beta1-4)-Glc-R oligosaccharide outer core of lgtB LPS with the dendritic-cell-specific ICAM-3 grabbing non-integrin (DC-SIGN) lectin receptor. Activation of DC-SIGN with this novel oligosaccharide ligand skewed T-cell responses driven by DC towards T helper type 1 activity. Thus, the use of lgtB LPS may provide a powerful instrument to selectively induce the desired arm of the immune response and potentially increase vaccine efficacy.

  19. Evaluation of in vivo labelled dendritic cell migration in cancer patients

    Directory of Open Access Journals (Sweden)

    Ridolfi Laura

    2004-07-01

    Full Text Available Abstract Background Dendritic Cell (DC vaccination is a very promising therapeutic strategy in cancer patients. The immunizing ability of DC is critically influenced by their migration activity to lymphatic tissues, where they have the task of priming naïve T-cells. In the present study in vivo DC migration was investigated within the context of a clinical trial of antitumor vaccination. In particular, we compared the migration activity of mature Dendritic Cells (mDC with that of immature Dendritic Cells (iDC and also assessed intradermal versus subcutaneous administration. Methods DC were labelled with 99mTc-HMPAO or 111In-Oxine, and the presence of labelled DC in regional lymph nodes was evaluated at pre-set times up to a maximum of 72 h after inoculation. Determinations were carried out in 8 patients (7 melanoma and 1 renal cell carcinoma. Results It was verified that intradermal administration resulted in about a threefold higher migration to lymph nodes than subcutaneous administration, while mDC showed, on average, a six-to eightfold higher migration than iDC. The first DC were detected in lymph nodes 20–60 min after inoculation and the maximum concentration was reached after 48–72 h. Conclusions These data obtained in vivo provide preliminary basic information on DC with respect to their antitumor immunization activity. Further research is needed to optimize the therapeutic potential of vaccination with DC.

  20. Evaluation of in vivo labelled dendritic cell migration in cancer patients.

    Science.gov (United States)

    Ridolfi, Ruggero; Riccobon, Angela; Galassi, Riccardo; Giorgetti, Gianluigi; Petrini, Massimiliano; Fiammenghi, Laura; Stefanelli, Monica; Ridolfi, Laura; Moretti, Andrea; Migliori, Giuseppe; Fiorentini, Giuseppe

    2004-07-30

    BACKGROUND: Dendritic Cell (DC) vaccination is a very promising therapeutic strategy in cancer patients. The immunizing ability of DC is critically influenced by their migration activity to lymphatic tissues, where they have the task of priming naïve T-cells. In the present study in vivo DC migration was investigated within the context of a clinical trial of antitumor vaccination. In particular, we compared the migration activity of mature Dendritic Cells (mDC) with that of immature Dendritic Cells (iDC) and also assessed intradermal versus subcutaneous administration. METHODS: DC were labelled with 99mTc-HMPAO or 111In-Oxine, and the presence of labelled DC in regional lymph nodes was evaluated at pre-set times up to a maximum of 72 h after inoculation. Determinations were carried out in 8 patients (7 melanoma and 1 renal cell carcinoma). RESULTS: It was verified that intradermal administration resulted in about a threefold higher migration to lymph nodes than subcutaneous administration, while mDC showed, on average, a six-to eightfold higher migration than iDC. The first DC were detected in lymph nodes 20-60 min after inoculation and the maximum concentration was reached after 48-72 h. CONCLUSIONS: These data obtained in vivo provide preliminary basic information on DC with respect to their antitumor immunization activity. Further research is needed to optimize the therapeutic potential of vaccination with DC.

  1. Proinsulin-expressing dendritic cells in type 2 neuropathic diabetic patients with and without foot lesions.

    Science.gov (United States)

    Sambataro, Maria; Sambado, Luisa; Trevisiol, Enrica; Cacciatore, Matilde; Furlan, Anna; Stefani, Piero Maria; Seganfreddo, Elena; Durante, Elisabetta; Conte, Stefania; Della Bella, Silvia; Paccagnella, Agostino; Dei Tos, Angelo Paolo

    2018-02-12

    Diabetic neuropathy is the most common complication of diabetes and is frequently associated with foot ischemia and infection, but its pathogenesis is controversial. We hypothesized that proinsulin expression in peripheral blood mononuclear cells is a process relevant to this condition and could represent a link among hyperglycemia, nerve susceptibility, and diabetic foot lesions. We assessed proinsulin expression by using flow cytometry in dendritic cells from control participants and patients with type 2 diabetic with or without peripheral neuropathy or accompanied by diabetic foot. Among 32 non-neuropathic and 120 neuropathic patients with type 2 diabetic, we performed leg electromyography and found average sensory sural nerve conduction velocities of 48 ± 4 and 30 ± 4 m/s, respectively ( P foot lesions, and 39 had neuroischemic foot lesions (allux oximetry diabetic population, but not in nondiabetic participants, a progressively increasing level of peripheral blood dendritic cell proinsulin expression was detected, which directly correlated with circulating TNF-α levels ( P diabetes, proinsulin-expressing blood cells, possibly via their involvement in innate immunity, may play a role in diabetic peripheral neuropathy and foot lesions.-Sambataro, M., Sambado, L., Trevisiol, E., Cacciatore, M., Furlan, A., Stefani, P. M., Seganfreddo, E., Durante, E., Conte, S., Della Bella, S., Paccagnella, A., dei Tos, A. P. Proinsulin-expressing dendritic cells in type 2 neuropathic diabetic patients with and without foot lesions.

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

    Directory of Open Access Journals (Sweden)

    Ying Pan

    Full Text Available 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.

  3. Impact of MAPK Pathway Activation in BRAFV600 Melanoma on T Cell and Dendritic Cell Function

    Directory of Open Access Journals (Sweden)

    Patrick A. Ott

    2013-10-01

    Full Text Available Constitutive upregulation of the MAPK pathway by a BRAFV600 mutation occurs in about half of melanomas. This leads to increased oncogenic properties such as tumor cell invasion, metastatic potential, and resistance to apoptosis. Blockade of the MAPK pathway with highly specific kinase inhibitors induces unprecedented tumor response rates in patients with advanced BRAFV600 mutant melanoma. Immune checkpoint blockade with monoclonal antibodies targeting cytotoxic T-lymphocyte antigen 4 and programed death-1/PD-L1 has also demonstrated striking anti-tumor activity in patients with advanced melanoma. Tumor responses are likely limited by multiple additional layers of immune suppression in the tumor microenvironment. There is emerging preclinical and clinical evidence suggesting that MAPK inhibition has a beneficial effect on the immunosuppressive tumor microenvironment, providing a strong rationale for combined immunotherapy and MAPK pathway inhibition in melanoma. The T cell response has been the main focus in the studies reported to date. Since dendritic cells (DCs are important in the induction of tumor-specific T cell responses, the impact of MAPK pathway activation in melanoma on DC function is critical for the melanoma directed immune response. BRAFV600E melanoma cells modulate DCs through the MAPK pathway because its blockade in melanoma cells can reverse suppression of DC function. As both MEK/BRAF inhibition and immune checkpoint blockade have recently taken center stage in the treatment of melanoma, a deeper understanding of how MAPK pathway inhibition affects the tumor immune response is needed.

  4. Comparison of alpha-Type-1 polarizing and standard dendritic cell cytokine cocktail for maturation of therapeutic monocyte-derived dendritic cell preparations from cancer patients

    DEFF Research Database (Denmark)

    Trepiakas, Redas; Pedersen, Anders Elm; Met, Ozcan

    2008-01-01

    The current "gold standard" for generation of dendritic cell (DC) used in DC-based cancer vaccine studies is maturation of monocyte-derived DCs with tumor necrosis factor-alpha (TNF-alpha)/IL-1beta/IL-6 and prostaglandin E(2) (PGE(2)). Recently, a protocol for producing so-called alpha-Type-1...... polarized dendritic cells (alphaDC1) in serum-free medium was published based on maturation of monocyte-derived DCs with TNF-alpha/IL-1-beta/polyinosinic:polycytidylic acid (poly-I:C)/interferon (IFN)-alpha and IFN-gamma. This DC maturation cocktail was described to fulfill the criteria for optimal DC......-regulation of inhibitory molecules such as PD-L1, ILT2, ILT3 as compared to sDC. Although alphaDC1 matured DCs secreted more IL-12p70 and IL-23 these DCs had lower or similar stimulatory capacity compared to sDCs when used as stimulating cells in mixed lymphocyte reaction (MLR) or for induction of autologous influenza...

  5. DNA and protein co-administration induces tolerogenic dendritic cells through DC-SIGN mediated negative signals.

    Science.gov (United States)

    Li, Jinyao; Geng, Shuang; Liu, Xiuping; Liu, Hu; Jin, Huali; Liu, Chang-Gong; Wang, Bin

    2013-10-01

    We previously demonstrated that DNA and protein co-administration induced differentiation of immature dendritic cells (iDCs) into CD11c(+)CD40(low)IL-10(+) regulatory DCs (DCregs) via the caveolin-1 (Cav-1) -mediated signal pathway. Here, we demonstrate that production of IL-10 and the low expression of CD40 play a critical role in the subsequent induction of regulatory T cells (Tregs) by the DCregs. We observed that DNA and protein were co-localized with DC-SIGN in caveolae and early lysosomes in the treated DCs, as indicated by co-localization with Cav-1 and EEA-1 compartment markers. DNA and protein also co-localized with LAMP-2. Gene-array analysis of gene expression showed that more than a thousand genes were significantly changed by the DC co-treatment with DNA + protein compared with controls. Notably, the level of DC-SIGN expression was dramatically upregulated in pOVA + OVA co-treated DCs. The expression levels of Rho and Rho GNEF, the down-stream molecules of DC-SIGN mediated signal pathway, were also greatly upregulated. Further, the level of TLR9, the traditional DNA receptor, was significantly downregulated. These results suggest that DC-SIGN as the potential receptor for DNA and protein might trigger the negative pathway to contribute the induction of DCreg combining with Cav-1 mediated negative signal pathway.

  6. Evaluating the Effects of Cytomegalovirus Glycoprotein B on the Maturation and Function of Monocyte-derived dendritic cells

    Directory of Open Access Journals (Sweden)

    Afsson shariat

    2015-11-01

    Full Text Available Background & Objectives: Interaction of cytomegalovirus glycoprotein B with toll-like receptors of dendritic cells leads to early signaling and innate immune responses. The aim of this study is to evaluate the effects of cytomegalovirus glycoprotein B on the maturation and function of monocyte-derived dendritic cells in treated groups in comparison with control groups. Materials & Methods: Blood samples were taken from 5 healthy volunteers. Following the generation of monocyte-derived dendritic cells on the fifth day of cell culture, half of the immature dendritic cells were treated with cytomegalovirus glycoprotein B, and the rest of them were induced to mature dendritic untreated cells and were used as the control group. The maturation and function of dendritic cells were evaluated in these two groups. Results: The gene expression level of toll-like receptor-4 significantly increased in the group treated with glycoprotein B (p < 0.05, whereas there were no significant differences in the expression rates of CD83, CD86, CD1a, and HLA-DR and the secretion of IL-23 from monocyte-derived dendritic cells between the treated groups and the controls. Conclusion: The increase in the gene expression of toll-like receptor-4 in monocyte-derived dendritic cells treated with cytomegalovirus glycoprotein B showed that cell contact is required to elicit cellular antiviral response and toll-like receptor activation. Thus, it is critical to recognize the viral and cellular determinants of the immune system in order to develop new therapeutic strategies against cytomegalovirus.

  7. Human regulatory B cells control the TFH cell response.

    Science.gov (United States)

    Achour, Achouak; Simon, Quentin; Mohr, Audrey; Séité, Jean-François; Youinou, Pierre; Bendaoud, Boutahar; Ghedira, Ibtissem; Pers, Jacques-Olivier; Jamin, Christophe

    2017-07-01

    Follicular helper T (T FH ) cells support terminal B-cell differentiation. Human regulatory B (Breg) cells modulate cellular responses, but their control of T FH cell-dependent humoral immune responses is unknown. We sought to assess the role of Breg cells on T FH cell development and function. Human T cells were polyclonally stimulated in the presence of IL-12 and IL-21 to generate T FH cells. They were cocultured with B cells to induce their terminal differentiation. Breg cells were included in these cultures, and their effects were evaluated by using flow cytometry and ELISA. B-cell lymphoma 6, IL-21, inducible costimulator, CXCR5, and programmed cell death protein 1 (PD-1) expressions increased on stimulated human T cells, characterizing T FH cell maturation. In cocultures they differentiated B cells into CD138 + plasma and IgD - CD27 + memory cells and triggered immunoglobulin secretions. Breg cells obtained by Toll-like receptor 9 and CD40 activation of B cells prevented T FH cell development. Added to T FH cell and B-cell cocultures, they inhibited B-cell differentiation, impeded immunoglobulin secretions, and expanded Foxp3 + CXCR5 + PD-1 + follicular regulatory T cells. Breg cells modulated IL-21 receptor expressions on T FH cells and B cells, and their suppressive activities involved CD40, CD80, CD86, and intercellular adhesion molecule interactions and required production of IL-10 and TGF-β. Human Breg cells control T FH cell maturation, expand follicular regulatory T cells, and inhibit the T FH cell-mediated antibody secretion. These novel observations demonstrate a role for the Breg cell in germinal center reactions and suggest that deficient activities might impair the T FH cell-dependent control of humoral immunity and might lead to the development of aberrant autoimmune responses. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  8. Dendrites of cerebellar granule cells correctly recognize their target axons for synaptogenesis in vitro.

    Science.gov (United States)

    Ito, Shoko; Takeichi, Masatoshi

    2009-08-04

    Neural circuits are generated by precisely ordered synaptic connections among neurons, and this process is thought to rely on the ability of neurons to recognize specific partners. However, it is also known that neurons promiscuously form synapses with nonspecific partners, in particular when cultured in vitro, causing controversies about neural recognition mechanisms. Here we reexamined whether neurons can or cannot select particular partners in vitro. In the cerebellum, granule cell (GC) dendrites form synaptic connections specifically with mossy fibers, but not with climbing fibers. We cocultured GC neurons with pontine or inferior olivary axons, the major sources for mossy and climbing fibers, respectively, as well as with hippocampal axons as a control. The GC neurons formed synapses with pontine axons predominantly at the distal ends of their dendrites, reproducing the characteristic morphology of their synapses observed in vivo, whereas they failed to do so when combined with other axons. In the latter case, synaptic proteins could accumulate between axons and dendrites, but these synapses were randomly distributed throughout the contact sites, and also their synaptic vesicle recycling was anomalous. These observations suggest that GC dendrites can select their authentic partners for synaptogenesis even in vitro, forming the synapses with a GC-specific nature only with them.

  9. Motor learning induces plastic changes in Purkinje cell dendritic spines in the rat cerebellum.

    Science.gov (United States)

    González-Tapia, D; González-Ramírez, M M; Vázquez-Hernández, N; González-Burgos, I

    2017-12-14

    The paramedian lobule of the cerebellum is involved in learning to correctly perform motor skills through practice. Dendritic spines are dynamic structures that regulate excitatory synaptic stimulation. We studied plastic changes occurring in the dendritic spines of Purkinje cells from the paramedian lobule of rats during motor learning. Adult male rats were trained over a 6-day period using an acrobatic motor learning paradigm; the density and type of dendritic spines were determined every day during the study period using a modified version of the Golgi method. The learning curve reflected a considerable decrease in the number of errors made by rats as the training period progressed. We observed more dendritic spines on days 2 and 6, particularly more thin spines on days 1, 3, and 6, fewer mushroom spines on day 3, fewer stubby spines on day 1, and more thick spines on days 4 and 6. The initial stage of motor learning may be associated with fast processing of the underlying synaptic information combined with an apparent "silencing" of memory consolidation processes, based on the regulation of the neuronal excitability. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  10. Dendritic cells support production of IgA and other non-IgM isotypes in clonal microculture.

    Science.gov (United States)

    Schrader, C E; George, A; Kerlin, R L; Cebra, J J

    1990-01-01

    Microcultures of helper T (Th) cells and a few appropriately primed murine B cells can be used to detect cognate T-B interactions which lead to clonal production of IgM, IgG1, and IgE. However, IgG2, IgG3, and IgA are very rarely expressed. We have found that the addition of dendritic cells to such cultures creates an extremely supportive environment for clones expressing IgA with other isotypes, as well as clones expressing only detectable IgA. Typically, 400 dendritic cells were added to 3000 conalbumin-specific Th cells (D10.G4.1) and 30 hapten-specific Peyer's patch (PP) B cells with antigen in 15 microliters. The response was antigen dependent and clonal. Almost half of the clones expressed only non-IgM isotypes, 43% expressed some IgA, and 14% expressed some IgG3; isotype diversity increased over time. Dendritic cells from PP and spleen were found to be equally supportive, and allowed the number of T cells required in microculture to be decreased from 3000 to 400. However, T cell proliferation was not required for the supportive effect of dendritic cells. Surface IgD-bearing cells were also found to switch to IgA production in microculture as judged by their generating clones expressing IgM along with IgA and other isotypes. Again, IgA was usually expressed only in the presence of dendritic cells. The mechanism may involve dendritic cell-induced T cell activation and/or dendritic cell factors, and is under investigation.

  11. Thy-1+ dendritic cells in murine epidermis are bone marrow-derived

    International Nuclear Information System (INIS)

    Breathnach, S.M.; Katz, S.I.

    1984-01-01

    Thy-1+, Ly-5+ dendritic cells have recently been described as a resident cell population in murine epidermis, but their ontogeny and function are unknown. The origin and turnover of epidermal Thy-1+ cells utilizing chimeric mice were investigated. Lethally x-irradiated AKR/J (Thy-1.1+) and AKR/Cum (Thy-1.2+) mice were reconstituted with allogeneic bone marrow cells with or without thymocytes from congenic AKR/Cum or AKR/J mice, respectively. The density of residual indigenous Thy-1.1+ cells in AKR/J chimeras and Thy-1.2+ cells in AKR/Cum chimeras was substantially reduced following x-irradiation, as determined by immunofluorescence staining of epidermal sheets. Epidermal repopulation by allogeneic Thy-1+ dendritic epidermal cells was first observed at 5 weeks in AKR/J chimeras and at 7 weeks in AKR/Cum chimeras and progressed slowly. Repopulation was not enhanced by increasing the number of allogeneic bone marrow cells injected from 2 X 10(7) to 10(8) cells or by the addition of 8 X 10(7) allogeneic thymocytes to the donor inoculate. Epidermal repopulation by allogeneic Thy-1.2+ cells was not seen in AKR/J mice reconstituted with syngeneic bone marrow cells and allogeneic Thy-1.2+ AKR/Cum thymocytes. Taken together, these results indicate that Thy-1+ dendritic epidermal cells are derived from the bone marrow and suggest that they are not related to conventional peripheral T-lymphocytes

  12. Circumvention of regulatory CD4(+) T cell activity during cross-priming strongly enhances T cell-mediated immunity.

    Science.gov (United States)

    Heit, Antje; Gebhardt, Friedemann; Lahl, Katharina; Neuenhahn, Michael; Schmitz, Frank; Anderl, Florian; Wagner, Hermann; Sparwasser, Tim; Busch, Dirk H; Kastenmüller, Kathrin

    2008-06-01

    Immunization with purified antigens is a safe and practical vaccination strategy but is generally unable to induce sustained CD8(+) T cell-mediated protection against intracellular pathogens. Most efforts to improve the CD8(+) T cell immunogenicity of these vaccines have focused on co-administration of adjuvant to support cross-presentation and dendritic cell maturation. In addition, it has been shown that CD4(+) T cell help during the priming phase contributes to the generation of protective CD8(+) memory T cells. In this report we demonstrate that the depletion of CD4(+) T cells paradoxically enhances long-lasting CD8-mediated protective immunity upon protein vaccination. Functional and genetic in vivo inactivation experiments attribute this enhancement primarily to MHC class II-restricted CD4(+) regulatory T cells (Treg), which appear to physiologically suppress the differentiation process towards long-living effector memory T cells. Since, in functional terms, this suppression by Treg largely exceeds the positive effects of conventional CD4(+) T cell help, even the absence of all CD4(+) T cells or lack of MHC class II-mediated interactions on priming dendritic cells result in enhanced CD8(+) T cell immunogenicity. These findings have important implications for the improvement of vaccines against intracellular pathogens or tumors, especially in patients with highly active Treg.

  13. Tolerogenic Dendritic Cells Generated with Tofacitinib Ameliorate Experimental Autoimmune Encephalomyelitis through Modulation of Th17/Treg Balance

    Directory of Open Access Journals (Sweden)

    Yan Zhou

    2016-01-01

    Full Text Available It is well known that dendritic cells (DCs play a pivotal role in triggering self-specific responses. Conversely, tolerogenic DCs (tolDCs, a specialized subset, induce tolerance and negatively regulate autoreactive responses. Tofacitinib, a Janus kinase inhibitor developed by Pfizer for treatment of rheumatoid arthritis, is probable to be a promising candidate for inducing tolDCs. The aims of this study were to evaluate the effectiveness of tolDCs induced by tofacitinib in a myelin oligodendrocyte glycoprotein- (MOG- specific experimental autoimmune encephalomyelitis (EAE model and to investigate their effects on Th17/Treg balance in the animal model of multiple sclerosis (MS. Our results revealed that tofacitinib-treated DCs maintained a steady semimature phenotype with a low level of proinflammatory cytokines and costimulatory molecules. DCs treated by tofacitinib also induced antigen-specific T cells hyporesponsiveness in a concentration-dependent manner. Upon intravenous injection into EAE mice, MOG pulsed tolDCs significantly dampened disease activity, and adoptive cell therapy (ACT disturbed Th17/Treg balance with a remarkable decrease of Th1/Th17 cells and an increase in regulatory T cells (Tregs. Overall, DCs modified by tofacitinib exhibited a typical tolerogenic phenotype, and the antigen-specific tolDCs may represent a new avenue of research for the development of future clinical treatments for MS.

  14. Yersinia outer proteins E, H, P, and T differentially target the cytoskeleton and inhibit phagocytic capacity of dendritic cells

    Czech Academy of Sciences Publication Activity Database

    Adkins, Irena; Köberle, M.; Gröbner, S.; Bohn, E.; Autenrieth, I. B.; Borgmann, S.

    2007-01-01

    Roč. 297, - (2007), s. 235-244 ISSN 1438-4221 Institutional research plan: CEZ:AV0Z50200510 Keywords : yersinia * yops * dendritic cell s Subject RIV: EC - Immunology Impact factor: 2.524, year: 2007

  15. Characterization of monocyte-derived dendritic cells maturated with IFN-alpha

    DEFF Research Database (Denmark)

    Svane, I M; Nikolajsen, K; Walter, M R

    2006-01-01

    Dendritic cells (DC) are promising candidates for cancer immunotherapy. These cells can be generated from peripheral blood monocytes cultured with granulocyte macrophage-colony stimulating factor (GM-CSF) and interleukin-4 (IL-4). In order to obtain full functional capacity, maturation is required......, maturation with IFN-alpha has only a small effect on induction of autologous T-cell stimulatory capacity of the DC. However, an increase in DC allogeneic T-cell stimulatory capacity was observed. These data suggest that IFN-alpha has a potential as a maturation agent used in DC-based cancer vaccine trials...

  16. Synergistic effects of dendritic cell targeting and laser-microporation on enhancing epicutaneous skin vaccination efficacy.

    Science.gov (United States)

    Machado, Yoan; Duinkerken, Sanne; Hoepflinger, Veronika; Mayr, Melissa; Korotchenko, Evgeniia; Kurtaj, Almedina; Pablos, Isabel; Steiner, Markus; Stoecklinger, Angelika; Lübbers, Joyce; Schmid, Maximillian; Ritter, Uwe; Scheiblhofer, Sandra; Ablinger, Michael; Wally, Verena; Hochmann, Sarah; Raninger, Anna M; Strunk, Dirk; van Kooyk, Yvette; Thalhamer, Josef; Weiss, Richard

    2017-11-28

    Due to its unique immunological properties, the skin is an attractive target tissue for allergen-specific immunotherapy. In our current work, we combined a dendritic cell targeting approach with epicutaneous immunization using an ablative fractional laser to generate defined micropores in the upper layers of the skin. By coupling the major birch pollen allergen Bet v 1 to mannan from S. cerevisiae via mild periodate oxidation we generated hypoallergenic Bet-mannan neoglycoconjugates, which efficiently targeted CD14 + dendritic cells and Langerhans cells in human skin explants. Mannan conjugation resulted in sustained release from the skin and retention in secondary lymphoid organs, whereas unconjugated antigen showed fast renal clearance. In a mouse model, Bet-mannan neoglycoconjugates applied via laser-microporated skin synergistically elicited potent humoral and cellular immune responses, superior to intradermal injection. The induced antibody responses displayed IgE-blocking capacity, highlighting the therapeutic potential of the approach. Moreover, application via micropores, but not by intradermal injection, resulted in a mixed TH1/TH17-biased immune response. Our data clearly show that applying mannan-neoglycoconjugates to an organ rich in dendritic cells using laser-microporation is superior to intradermal injection. Due to their low IgE binding capacity and biodegradability, mannan neoglycoconjugates therefore represent an attractive formulation for allergen-specific epicutaneous immunotherapy. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Dendritic cell-associated immune inflammation of cardiac mucosa: a possible factor in the formation of Barrett's esophagus.

    Science.gov (United States)

    Bobryshev, Yuri V; Tran, Dinh; Killingsworth, Murray C; Buckland, Michael; Lord, Reginald V N

    2009-03-01

    The development of Barrett's esophagus is poorly understood, but it has been suggested that cardiac mucosa is a precursor of intestinal type metaplasia and that inflammation of cardiac mucosa may play a role in the formation of Barrett's esophagus. The present study was undertaken to examine the presence and distribution of immune-inflammatory cells in cardiac mucosa, specifically focusing on dendritic cells because of their importance as regulators of immune reactions. Endoscopic biopsy specimens were obtained from 12 patients with cardiac mucosa without Barrett's esophagus or adenocarcinoma and from 21 patients with Barrett's esophagus without dysplasia (intestinal metaplasia). According to histology, in nine of the 21 specimens with Barrett's esophagus, areas of mucosa composed of cardiac type epithelium-lined glands were present as well. Immunohistochemical staining and electron microscopy were used to examine immune-inflammatory cells in paraffin-embedded sections. Immune-inflammatory cells, including T cells, B cells, dendritic cells, macrophages, and mast cells, were present in the connective tissue matrix that surrounded cardiac type epithelium-lined glands in all patients with cardiac mucosa. Clustering of dendritic cells with each other and with lymphocytes and the intrusion of dendritic cells between glandular mucus cells were observed. In the Barrett's esophagus specimens that contained cardiac type glands, computerized CD83 expression quantitation revealed that there were more dendritic cells in cardiac mucosa than in intestinal metaplasia. Immune-inflammatory infiltrates containing dendritic cells are consistently present in cardiac mucosa. The finding of a larger number of dendritic cells in areas of cardiac mucosa in Barrett's esophagus biopsies suggests that the immune inflammation of cardiac mucosa might play a role in modifying the local tissue environment to promote the development of specialized intestinal type metaplasia.

  18. DMPD: Pivotal role of PGE2 and IL-10 in the cross-regulation of dendritic cell-derivedinflammatory mediators. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available l) (.csml) Show Pivotal role of PGE2 and IL-10 in the cross-regulation of dendritic cell-derivedinflammatory mediator...egulation of dendritic cell-derivedinflammatory mediators. Authors Harizi H, Gualde N. Publication Cell Mol ...16978535 Pivotal role of PGE2 and IL-10 in the cross-regulation of dendritic cell-derivedinflammatory mediat...ors. Harizi H, Gualde N. Cell Mol Immunol. 2006 Aug;3(4):271-7. (.png) (.svg) (.htm

  19. T cell resistance to activation by dendritic cells requires long-term culture in simulated microgravity

    Science.gov (United States)

    Bradley, Jillian H.; Stein, Rachel; Randolph, Brad; Molina, Emily; Arnold, Jennifer P.; Gregg, Randal K.

    2017-11-01

    Immune impairment mediated by microgravity threatens the success of space exploration requiring long-duration spaceflight. The cells of most concern, T lymphocytes, coordinate the host response against microbial and cancerous challenges leading to elimination and long-term protection. T cells are activated upon recognition of specific microbial peptides bound on the surface of antigen presenting cells, such as dendritic cells (DC). Subsequently, this engagement results in T cell proliferation and differentiation into effector T cells driven by autocrine interleukin-2 (IL-2) and other cytokines. Finally, the effector T cells acquire the weaponry needed to destroy microbial invaders and tumors. Studies conducted on T cells during spaceflight, or using Earth-based culture systems, have shown reduced production of cytokines, proliferation and effector functions as compared to controls. This may account for the cases of viral reactivation events and opportunistic infections associated with astronauts of numerous missions. This work has largely been based upon the outcome of T cell activation by stimulatory factors that target select T cell signaling pathways rather than the complex, signaling events related to the natural process of antigen presentation by DC. This study tested the response of an ovalbumin peptide-specific T cell line, OT-II TCH, to activation by DC when the T cells were cultured 24-120 h in a simulated microgravity (SMG) environment generated by a rotary cell culture system. Following 72 h culture of T cells in SMG (SMG-T) or control static (Static-T) conditions, IL-2 production by the T cells was reduced in SMG-T cells compared to Static-T cells upon stimulation by phorbol 12-myristate 13-acetate (PMA) and ionomycin. However, when the SMG-T cells were stimulated with DC and peptide, IL-2 was significantly increased compared to Static-T cells. Such enhanced IL-2 production by SMG-T cells peaked at 72 h SMG culture time and decreased thereafter. When

  20. T cell resistance to activation by dendritic cells requires long-term culture in simulated microgravity.

    Science.gov (United States)

    Bradley, Jillian H; Stein, Rachel; Randolph, Brad; Molina, Emily; Arnold, Jennifer P; Gregg, Randal K

    2017-11-01

    Immune impairment mediated by microgravity threatens the success of space exploration requiring long-duration spaceflight. The cells of most concern, T lymphocytes, coordinate the host response against microbial and cancerous challenges leading to elimination and long-term protection. T cells are activated upon recognition of specific microbial peptides bound on the surface of antigen presenting cells, such as dendritic cells (DC). Subsequently, this engagement results in T cell proliferation and differentiation into effector T cells driven by autocrine interleukin-2 (IL-2) and other cytokines. Finally, the effector T cells acquire the weaponry needed to destroy microbial invaders and tumors. Studies conducted on T cells during spaceflight, or using Earth-based culture systems, have shown reduced production of cytokines, proliferation and effector functions as compared to controls. This may account for the cases of viral reactivation events and opportunistic infections associated with astronauts of numerous missions. This work has largely been based upon the outcome of T cell activation by stimulatory factors that target select T cell signaling pathways rather than the complex, signaling events related to the natural process of antigen presentation by DC. This study tested the response of an ovalbumin peptide-specific T cell line, OT-II TCH, to activation by DC when the T cells were cultured 24-120 h in a simulated microgravity (SMG) environment generated by a rotary cell culture system. Following 72 h culture of T cells in SMG (SMG-T) or control static (Static-T) conditions, IL-2 production by the T cells was reduced in SMG-T cells compared to Static-T cells upon stimulation by phorbol 12-myristate 13-acetate (PMA) and ionomycin. However, when the SMG-T cells were stimulated with DC and peptide, IL-2 was significantly increased compared to Static-T cells. Such enhanced IL-2 production by SMG-T cells peaked at 72 h SMG culture time and decreased thereafter

  1. Modified vaccinia virus Ankara triggers type I IFN production in murine conventional dendritic cells via a cGAS/STING-mediated cytosolic DNA-sensing pathway.

    Directory of Open Access Journals (Sweden)

    Peihong Dai

    2014-04-01

    Full Text Available Modified vaccinia virus Ankara (MVA is an attenuated poxvirus that has been engineered as a vaccine against infectious agents and cancers. Our goal is to understand how MVA modulates innate immunity in dendritic cells (DCs, which can provide insights to vaccine design. In this study, using murine bone marrow-derived dendritic cells, we assessed type I interferon (IFN gene induction and protein secretion in response to MVA infection. We report that MVA infection elicits the production of type I IFN in murine conventional dendritic cells (cDCs, but not in plasmacytoid dendritic cells (pDCs. Transcription factors IRF3 (IFN regulatory factor 3 and IRF7, and the positive feedback loop mediated by IFNAR1 (IFN alpha/beta receptor 1, are required for the induction. MVA induction of type I IFN is fully dependent on STING (stimulator of IFN genes and the newly discovered cytosolic DNA sensor cGAS (cyclic guanosine monophosphate-adenosine monophosphate synthase. MVA infection of cDCs triggers phosphorylation of TBK1 (Tank-binding kinase 1 and IRF3, which is abolished in the absence of cGAS and STING. Furthermore, intravenous delivery of MVA induces type I IFN in wild-type mice, but not in mice lacking STING or IRF3. Treatment of cDCs with inhibitors of endosomal and lysosomal acidification or the lysosomal enzyme Cathepsin B attenuated MVA-induced type I IFN production, indicating that lysosomal enzymatic processing of virions is important for MVA sensing. Taken together, our results demonstrate a critical role of the cGAS/STING-mediated cytosolic DNA-sensing pathway for type I IFN induction in cDCs by MVA. We present evidence that vaccinia virulence factors E3 and N1 inhibit the activation of IRF3 and the induction of IFNB gene in MVA-infected cDCs.

  2. Evaluation of Immune Responses Mediated by Listeria-Stimulated Human Dendritic Cells: Implications for Cancer Vaccine Therapy

    Science.gov (United States)

    2013-07-01

    transfected with RNA. NatBiotech. 1998;16:364-369. 20. Heiser A, Dahm P, Yancey DR, et al. Human dendritic cells transfected with RNA encoding prostate...specific antigen stimulate prostate-specific CTL responses in vitro. J Immunol. 2000;164(10):5508-5514. 21. Heiser A, Maurice MA, Yancey DR...primary and metastatic tumors. Cancer Res. 2001;61(8):3388-3393. 22. Heiser A, Coleman D, Dannull J, et al. Autologous dendritic cells transfected

  3. Dendritic cells and immuno-modulation in autoimmune arthritis

    NARCIS (Netherlands)

    Spiering, R.|info:eu-repo/dai/nl/313939020

    2013-01-01

    The immune system consists of a broad array of immune cells to protect the body against invasive pathogenic microorganisms. Immune responses should however, be tightly controlled to ensure tolerance to the body’s own cells and proteins in order to limit damage to the host own cells and tissue.

  4. Dendritic cells that phagocytose apoptotic macrophages loaded with mycobacterial antigens activate CD8 T cells via cross-presentation

    OpenAIRE

    Espinosa-Cueto, Patricia; Magallanes-Puebla, Alejandro; Castellanos, Carlos; Mancilla, Raul

    2017-01-01

    While homeostatic apoptosis is immunologically silent, macrophage apoptosis during Mycobacterium tuberculosis infection can potentially induce an immune response against the mycobacteria. To examine the role of dendritic cells in this response, macrophage apoptosis was induced by incubating the macrophage with cell wall extracts of mycobacteria expressing LpqH. The apoptogenic proteins of the cell wall extracts were engulfed by the macrophage and then were translocated from the cytosol to the...

  5. Donor lung derived myeloid and plasmacytoid dendritic cells differentially regulate T cell proliferation and cytokine production

    Directory of Open Access Journals (Sweden)

    Benson Heather L

    2012-03-01

    Full Text Available Abstract Background Direct allorecognition, i.e., donor lung-derived dendritic cells (DCs stimulating recipient-derived T lymphocytes, is believed to be the key mechanism of lung allograft rejection. Myeloid (cDCs and plasmacytoid (pDCs are believed to have differential effects on T cell activation. However, the roles of each DC type on T cell activation and rejection pathology post lung transplantation are unknown. Methods Using transgenic mice and antibody depletion techniques, either or both cell types were depleted in lungs of donor BALB/c mice (H-2d prior to transplanting into C57BL/6 mice (H-2b, followed by an assessment of rejection pathology, and pDC or cDC-induced proliferation and cytokine production in C57BL/6-derived mediastinal lymph node T cells (CD3+. Results Depleting either DC type had modest effect on rejection pathology and T cell proliferation. In contrast, T cells from mice that received grafts depleted of both DCs did not proliferate and this was associated with significantly reduced acute rejection scores compared to all other groups. cDCs were potent inducers of IFNγ, whereas both cDCs and pDCs induced IL-10. Both cell types had variable effects on IL-17A production. Conclusion Collectively, the data show that direct allorecognition by donor lung pDCs and cDCs have differential effects on T cell proliferation and cytokine production. Depletion of both donor lung cDC and pDC could prevent the severity of acute rejection episodes.

  6. Expression profiling on high-density DNA grids to detect novel targets in dendritic cells

    International Nuclear Information System (INIS)

    Weissmann, M.

    2000-10-01

    Gene expression analyzes on a large scale using DNA microarrays is a novel approach to study transcription of thousands of genes in parallel. By comparing gene expression profiles of different cell-types and of cells in different activation, novel regulatory networks will be identified that are unique to a cell-type and hence, important in its biological function. Among the differentially expressed genes many novel drug targets will be found. The Genetic department of the Novartis Research Institute was following this approach to identify novel genes, which are critical in the antigen presenting function of DCs and could become promising drug targets. Drugs that modulate effector functions of DCs towards induction of energy or tolerance in T-cells could be useful in the treatment of chronic inflammatory or autoimmune diseases. By using specific robotics equipment high-density cDNA grids on nylon membranes have been produced for hybridizations with various radioactive labeled DNA probes. By our format, based on 384 well plates and limited by the resolution power of our current image analysis software, 27.648 cDNA clones, bacterial colonies or pure DNA, were spotted on one filter. For RNA profiling, we generated filters containing a collection of genes expressed in peripheral blood DCs or monocytes and characterized by oligonucleotide fingerprinting (ONF) as being differentially expressed. The gene collection contained many unknown genes. Sequence analysis of to date 18.000 cDNA clones led to an estimate of 5.000 non-redundant genes being represented in the collection. 10 % of them are either completely unknown or homologous to rare ESTs (expressed sequence tags) in the public EST database. These clones occurred predominantly in small fingerprint clusters and were therefore assumed to be rarely expressed in DCs or monocytes. Some of those genes may become novel drug targets if their expression is DC specific or induced by external stimuli driving DCs into

  7. Tumour-inhibitory effects of dendritic cells administered at the site of HPV 16-induced neoplasms

    Czech Academy of Sciences Publication Activity Database

    Mendoza, Luis; Bubeník, Jan; Šímová, Jana; Korb, Jan; Bieblová, Jana; Vonka, V.; Indrová, Marie; Mikyšková, Romana; Jandlová, Táňa

    2002-01-01

    Roč. 48, č. 3 (2002), s. 114-119 ISSN 0015-5500 R&D Projects: GA MZd NC7148; GA ČR GA301/00/0114; GA AV ČR IAA7052002; GA AV ČR IAA5052203 Institutional research plan: CEZ:AV0Z5052915 Keywords : HPV 16 * dendritic cells * adjuvant therapy Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.615, year: 2002

  8. Dendritic Cell Targeted Chitosan Nanoparticles for Nasal DNA Immunization against SARS CoV Nucleocapsid Protein

    OpenAIRE

    Raghuwanshi, Dharmendra; Mishra, Vivek; Das, Dipankar; Kaur, Kamaljit; Suresh, Mavanur R.

    2012-01-01

    This work investigates the formulation and in vivo efficacy of dendritic cell (DC) targeted plasmid DNA loaded biotinylated chitosan nanoparticles for nasal immunization against nucleocapsid (N) protein of severe acute respiratory syndrome coronavirus (SARS-CoV) as antigen. The induction of antigen-specific mucosal and systemic immune response at the site of virus entry is a major challenge for vaccine design. Here, we designed a strategy for non-invasive receptor mediated gene delivery to na...

  9. Cytokines and dendritic cells as adjuvants for therapy of HPV16-associated tumours

    Czech Academy of Sciences Publication Activity Database

    Bubeník, Jan; Mikyšková, Romana; Reiniš, Milan; Mendoza, Luis; Indrová, Marie; Šmahel, M.; Vonka, V.

    2003-01-01

    Roč. 12, Supplement 1 (2003), s. S7 ISSN 1107-3756. [The 8th World Congress on Advances in Oncology and 6th Internationl Symposium on Molecular Medicine . Hernissos, Crete, 16.10.2003-18.10.2003] Institutional research plan: CEZ:AV0Z5052915 Keywords : HPV16 * dendritic cells * cytokines Subject RIV: FD - Oncology ; Hematology Impact factor: 1.940, year: 2003

  10. HPV16-associated tumours: Therapy of surgical minimal residual disease with dendritic cell-based vaccines

    Czech Academy of Sciences Publication Activity Database

    Reiniš, Milan; Indrová, Marie; Mendoza, Luis; Mikyšková, Romana; Bieblová, Jana; Bubeník, Jan; Šímová, Jana

    2004-01-01

    Roč. 25, č. 4 (2004), s. 1165-1170 ISSN 1019-6439 R&D Projects: GA MZd NC7148; GA ČR GA301/04/0492; GA ČR GA301/01/0985; GA AV ČR IAA5052203 Institutional research plan: CEZ:AV0Z5052915 Keywords : HPV16 * minimal residual tumour disease * dendritic cells Subject RIV: EC - Immunology Impact factor: 3.056, year: 2004

  11. Efficacy of a therapeutic vaccine using mutated β-amyloid sensitized dendritic cells in Alzheimer's mice.

    Science.gov (United States)

    Luo, Zhongqiu; Li, Jialin; Nabar, Neel R; Lin, Xiaoyang; Bai, Ge; Cai, Jianfeng; Zhou, Shu-Feng; Cao, Chuanhai; Wang, Jinhuan

    2012-09-01

    Despite FDA suspension of Elan's AN-1792 amyloid beta (Aβ) vaccine in phase IIb clinical trials, the implications of this study are the guiding principles for contemporary anti-Aβ immunotherapy against Alzheimer's disease (AD). AN-1792 showed promising results with regards to Aβ clearance and cognitive function improvement, but also exhibited an increased risk of Th1 mediated meningoencephalitis. As such, vaccine development has continued with an emphasis on eliciting a notable anti-Aβ antibody titer, while avoiding the unwanted Th1 pro-inflammatory response. Previously, we published the first report of an Aβ sensitized dendritic cell vaccine as a therapeutic treatment for AD in BALB/c mice. Our vaccine elicited an anti-Aβ titer, with indications that a Th1 response was not present. This study is the first to investigate the efficacy and safety of our dendritic cell vaccine for the prevention of AD in transgenic mouse models (PDAPP) for AD. We also used Immunohistochemistry to characterize the involvement of LXR, ABCA1, and CD45 in order to gain insight into the potential mechanisms through which this vaccine may provide benefit. The results indicate that (1) the use of mutant Aβ1-42 sensitized dendritic cell vaccine results in durable antibody production, (2) the vaccine provides significant benefits with regards to cognitive function without the global (Th1) inflammation seen in prior Aβ vaccines, (3) histological studies showed an overall decrease in Aβ burden, with an increase in LXR, ABCA1, and CD45, and (4) the beneficial results of our DC vaccine may be due to the LXR/ABCA1 pathway. In the future, mutant Aβ sensitized dendritic cell vaccines could be an efficacious and safe method for the prevention or treatment of AD that circumvents problems associated with traditional anti-Aβ vaccines.

  12. Dendritic Cells from Peyer's Patches and Mesenteric Lymph Nodes Differ from Spleen Dendritic Cells in their Response to Commensal Gut Bacteria

    DEFF Research Database (Denmark)

    Fink, Lisbeth Nielsen; Frøkiær, Hanne

    2008-01-01

    . Expression of CCR7 and CD103 on the surface of MLN DC, necessary for the induction of gut-homing regulatory T cells, increased with stimulation by Gram-positive commensals. Bacteria-dependent cytokine production (IL-6, IL-10 and TNF-alpha) was similar in spleen and MLN DC, and contaminant cells in these DC...

  13. Lactobacilli activate human dendritic cells that skew T cells toward T helper 1 polarization.

    Science.gov (United States)

    Mohamadzadeh, Mansour; Olson, Scott; Kalina, Warren V; Ruthel, Gordon; Demmin, Gretchen L; Warfield, Kelly L; Bavari, Sina; Klaenhammer, Todd R

    2005-02-22

    Professional antigen-presenting dendritic cells (DCs) are critical in regulating T cell immune responses at both systemic and mucosal sites. Many Lactobacillus species are normal members of the human gut microflora and most are regarded as safe when administered as probiotics. Because DCs can naturally or therapeutically encounter lactobacilli, we investigated the effects of several well defined strains, representing three species of Lactobacillus on human myeloid DCs (MDCs) and found that they modulated the phenotype and functions of human MDCs. Lactobacillus-exposed MDCs up-regulated HLA-DR, CD83, CD40, CD80, and CD86 and secreted high levels of IL-12 and IL-18, but not IL-10. IL-12 was sustained in MDCs exposed to all three Lactobacillus species in the presence of LPS from Escherichia coli, whereas LPS-induced IL-10 was greatly inhibited. MDCs activated with lactobacilli clearly skewed CD4(+) and CD8(+) T cells to T helper 1 and Tc1 polarization, as evidenced by secretion of IFN-gamma, but not IL-4 or IL-13. These results emphasize a potentially important role for lactobacilli in modulating immunological functions of DCs and suggest that certain strains could be particularly advantageous as vaccine adjuvants, by promoting DCs to regulate T cell responses toward T helper 1 and Tc1 pathways.

  14. Inhibition of cathepsin X enzyme influences the immune response of THP-1 cells and dendritic cells infected with Helicobacter pylori

    International Nuclear Information System (INIS)

    Skvarc, Miha; Stubljar, David; Kopitar, Andreja Natasa; Jeverica, Samo; Tepes, Bojan; Kos, Janko; Ihan, Alojz

    2013-01-01

    The immune response to Helicobacter pylori importantly determines the outcome of infection as well as the success of eradication therapy. We demonstrate the role of a cysteine protease cathepsin X in the immune response to H. pylori infection. We analysed how the inhibition of cathepsin X influenced the immune response in experiments when THP-1 cells or dendritic cells isolated from patients were stimulated with 48 strains of H. pylori isolated from gastric biopsy samples of patients which had problems with the eradication of bacteria. The experiments, performed with the help of a flow cytometer, showed that the expression of Toll-like receptors (TLRs), especially TLR-4 molecules, on the membranes of THP-1 cells or dendritic cells was higher when we stimulated cells with H. pylori together with inhibitor of cathepsin X 2F12 compared to THP-1 cells or dendritic cells stimulated with H. pylori only, and also in comparison with negative control samples. We also demonstrated that when we inhibited the action of cathepsin X in THP-1 cells, the concentrations of pro-inflammatory cytokines were lower than when THP-1 cell were stimulated with H. pylori only. We demonstrated that inhibition of cathepsin X influences the internalization of TLR-2 and TLR-4. TLR-2 and TLR-4 redistribution to intra-cytoplasmic compartments is hampered if cathepsin X is blocked. The beginning of a successful immune response against H. pylori in the case of inhibition of cathepsin X is delayed

  15. Proliferating cells in psoriatic dermis are comprised primarily of T cells, endothelial cells, and factor XIIIa+ perivascular dendritic cells

    International Nuclear Information System (INIS)

    Morganroth, G.S.; Chan, L.S.; Weinstein, G.D.; Voorhees, J.J.; Cooper, K.D.

    1991-01-01

    Determination of the cell types proliferating in the dermis of patients with psoriasis should identify those cells experiencing activation or responding to growth factors in the psoriatic dermal milieu. Toward that end, sections of formalin-fixed biopsies obtained from 3H-deoxyuridine (3H-dU)-injected skin of eight psoriatic patients were immunostained, followed by autoradiography. Proliferating dermal cells exhibit silver grains from tritium emissions. The identity of the proliferating cells could then be determined by simultaneous visualization with antibodies specific for various cell types. UCHL1+ (CD45RO+) T cells (recall antigen-reactive helper T-cell subset) constituted 36.6 +/- 3.1% (mean +/- SEM, n = 6) of the proliferating dermal cells in involved skin, whereas Leu 18+ (CD45RA+) T cells (recall antigen naive T-cell subsets) comprised only 8.7 +/- 1.5% (n = 6). The Factor XIIIa+ dermal perivascular dendritic cell subset (24.9 +/- 1.5% of proliferating dermal cells, n = 6) and Factor VIII+ endothelial cells represented the two other major proliferating populations in lesional psoriatic dermis. Differentiated tissue macrophages, identified by phase microscopy as melanophages or by immunostaining with antibodies to Leu M1 (CD15) or myeloid histiocyte antigen, comprised less than 5% of the proliferating population in either skin type. In addition to calculating the relative proportions of these cells to each other as percent, we also determined the density of cells, in cells/mm2 of tissue. The density of proliferating cells within these populations was increased in involved versus uninvolved skin: UCHL1+, 9.0 +/- 1.7 cells/mm2 versus 1.8 +/- 0.6 cells/mm2, p less than 0.01; Factor XIIIa+, 6.0 +/- 0.7 cells/mm2 versus 1.5 +/- 0.5 cells/mm2, p less than 0.01; Factor VIII+, 5.5 +/- 1.4 cells/mm2 versus 0.0 cells/mm2, p less than 0.05

  16. Optimization of dendritic cell loading with tumor cell lysates for cancer immunotherapy.

    Science.gov (United States)

    Hatfield, Paul; Merrick, Alison E; West, Emma; O'Donnell, Dearbhaile; Selby, Peter; Vile, Richard; Melcher, Alan A

    2008-09-01

    The immune response to cancer is critically determined by the way in which tumor cells die. As necrotic, stress-associated death can be associated with activation of antitumor immunity, whole tumor cell antigen loading strategies for dendritic cell (DC)-based vaccination have commonly used freeze-thaw "necrotic" lysates as an immunogenic source of tumor-associated antigens. In this study, the effect of such lysates on the ability of DCs to mature in response to well-established maturation stimuli was examined, and methods to enhance lysate-induced DC activation explored. Freeze-thaw lysates were prepared from murine tumor cell lines and their effects on bone marrow-derived DC maturation and function examined. Unmodified freeze-thaw tumor cell lysates inhibited the toll-like receptor-induced maturation and function of bone marrow-derived DCs, preventing up-regulation of CD40, CD86, and major histocompatibility complex class II, and reducing secretion of inflammatory cytokines [interleukin (IL)-12 p70, tumor necrosis factor-alpha, and IL-6]. Although IL-10 secretion was increased by lysate-pulsed DCs, this was not responsible for the observed suppression of IL-12. Although activation of the nuclear factor-kappaB pathway remained intact, the kinase activity of phosphorylated p38 mitogen-activated protein kinase was inhibited in lysate-pulsed DCs. Lysate-induced DC suppression was partially reversed in vitro by induction of tumor cell stress before lysis, and only DCs loaded with stressed lysates afforded protection against tumor challenge in vivo. These data suggest that ex vivo freeze-thaw of tumor cells does not effectively mimic in vivo immunogenic necrosis, and advocates careful characterization and optimization of tumor cell-derived vaccine sources for cancer immunotherapy.

  17. Targeting of tolerogenic dendritic cells towards heat-shock proteins: a novel therapeutic strategy for autoimmune diseases?

    Science.gov (United States)

    Jansen, Manon A A; Spiering, Rachel; Broere, Femke; van Laar, Jacob M; Isaacs, John D; van Eden, Willem; Hilkens, Catharien M U

    2018-01-01

    Tolerogenic dendritic<