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Sample records for alter dendritic cell

  1. The extent to which melanoma alters tissue-resident dendritic cell function correlates with tumorigenicity

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    Hargadon, Kristian Michael

    2015-01-01

    ABSTRACT We have shown that melanoma-derived factors alter the function of differentiated tissue-resident dendritic cells (DC) in a tumorigenicity-dependent manner. Soluble factors, including TGF?1 and VEGF-A, contributed to dendritic cell dysfunction associated with a highly-aggressive melanoma and conferred a phenotype upon DC likely to favor immune escape and tumor outgrowth.

  2. The extent to which melanoma alters tissue-resident dendritic cell function correlates with tumorigenicity.

    Science.gov (United States)

    Hargadon, Kristian Michael

    We have shown that melanoma-derived factors alter the function of differentiated tissue-resident dendritic cells (DC) in a tumorigenicity-dependent manner. Soluble factors, including TGFβ1 and VEGF-A, contributed to dendritic cell dysfunction associated with a highly-aggressive melanoma and conferred a phenotype upon DC likely to favor immune escape and tumor outgrowth.

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

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    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.

  4. Genome wide transcriptome analysis of dendritic cells identifies genes with altered expression in psoriasis.

    Science.gov (United States)

    Filkor, Kata; Hegedűs, Zoltán; Szász, András; Tubak, Vilmos; Kemény, Lajos; Kondorosi, Éva; Nagy, István

    2013-01-01

    Activation of dendritic cells by different pathogens induces the secretion of proinflammatory mediators resulting in local inflammation. Importantly, innate immunity must be properly controlled, as its continuous activation leads to the development of chronic inflammatory diseases such as psoriasis. Lipopolysaccharide (LPS) or peptidoglycan (PGN) induced tolerance, a phenomenon of transient unresponsiveness of cells to repeated or prolonged stimulation, proved valuable model for the study of chronic inflammation. Thus, the aim of this study was the identification of the transcriptional diversity of primary human immature dendritic cells (iDCs) upon PGN induced tolerance. Using SAGE-Seq approach, a tag-based transcriptome sequencing method, we investigated gene expression changes of primary human iDCs upon stimulation or restimulation with Staphylococcus aureus derived PGN, a widely used TLR2 ligand. Based on the expression pattern of the altered genes, we identified non-tolerizeable and tolerizeable genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (Kegg) analysis showed marked enrichment of immune-, cell cycle- and apoptosis related genes. In parallel to the marked induction of proinflammatory mediators, negative feedback regulators of innate immunity, such as TNFAIP3, TNFAIP8, Tyro3 and Mer are markedly downregulated in tolerant cells. We also demonstrate, that the expression pattern of TNFAIP3 and TNFAIP8 is altered in both lesional, and non-lesional skin of psoriatic patients. Finally, we show that pretreatment of immature dendritic cells with anti-TNF-α inhibits the expression of IL-6 and CCL1 in tolerant iDCs and partially releases the suppression of TNFAIP8. Our findings suggest that after PGN stimulation/restimulation the host cell utilizes different mechanisms in order to maintain critical balance between inflammation and tolerance. Importantly, the transcriptome sequencing of stimulated/restimulated iDCs identified numerous genes with

  5. Genome wide transcriptome analysis of dendritic cells identifies genes with altered expression in psoriasis.

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    Kata Filkor

    Full Text Available Activation of dendritic cells by different pathogens induces the secretion of proinflammatory mediators resulting in local inflammation. Importantly, innate immunity must be properly controlled, as its continuous activation leads to the development of chronic inflammatory diseases such as psoriasis. Lipopolysaccharide (LPS or peptidoglycan (PGN induced tolerance, a phenomenon of transient unresponsiveness of cells to repeated or prolonged stimulation, proved valuable model for the study of chronic inflammation. Thus, the aim of this study was the identification of the transcriptional diversity of primary human immature dendritic cells (iDCs upon PGN induced tolerance. Using SAGE-Seq approach, a tag-based transcriptome sequencing method, we investigated gene expression changes of primary human iDCs upon stimulation or restimulation with Staphylococcus aureus derived PGN, a widely used TLR2 ligand. Based on the expression pattern of the altered genes, we identified non-tolerizeable and tolerizeable genes. Gene Ontology (GO and Kyoto Encyclopedia of Genes and Genomes (Kegg analysis showed marked enrichment of immune-, cell cycle- and apoptosis related genes. In parallel to the marked induction of proinflammatory mediators, negative feedback regulators of innate immunity, such as TNFAIP3, TNFAIP8, Tyro3 and Mer are markedly downregulated in tolerant cells. We also demonstrate, that the expression pattern of TNFAIP3 and TNFAIP8 is altered in both lesional, and non-lesional skin of psoriatic patients. Finally, we show that pretreatment of immature dendritic cells with anti-TNF-α inhibits the expression of IL-6 and CCL1 in tolerant iDCs and partially releases the suppression of TNFAIP8. Our findings suggest that after PGN stimulation/restimulation the host cell utilizes different mechanisms in order to maintain critical balance between inflammation and tolerance. Importantly, the transcriptome sequencing of stimulated/restimulated iDCs identified

  6. Tumor-altered dendritic cell function: implications for anti-tumor immunity

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    Kristian Michael Hargadon

    2013-07-01

    Full Text Available Dendritic cells are key regulators of both innate and adaptive immunity, and the array of immunoregulatory functions exhibited by these cells is dictated by their differentiation, maturation, and activation status. Although a major role for these cells in the induction of immunity to pathogens has long been appreciated, data accumulated over the last several years has demonstrated that DC are also critical regulators of anti-tumor immune responses. However, despite the potential for stimulation of robust anti-tumor immunity by DC, tumor-altered DC function has been observed in many cancer patients and tumor-bearing animals and is often associated with tumor immune escape. Such dysfunction has significant implications for both the induction of natural anti-tumor immune responses as well as the efficacy of immunotherapeutic strategies that target endogenous DC in situ or that employ exogenous DC as part of anti-cancer immunization maneuvers. In this review, the major types of tumor-altered DC function will be described, with emphasis on recent insights into the mechanistic bases for the inhibition of DC differentiation from hematopoietic precursors, the altered programming of DC precursors to differentiate into myeloid-derived suppressor cells or tumor-associated macrophages, the suppression of DC maturation and activation, and the induction of immunoregulatory DC by tumors, tumor-derived factors, and tumor-associated cells within the milieu of the tumor microenvironment. The impact of these tumor-altered cells on the quality of the overall anti-tumor immune response will also be discussed. Finally, this review will also highlight questions concerning tumor-altered DC function that remain unanswered, and it will address factors that have limited advances in the study of this phenomenon in order to focus future research efforts in the field on identifying strategies for interfering with tumor-associated DC dysfunction and improving DC-mediated anti

  7. Tumor-altered dendritic cell function: implications for anti-tumor immunity.

    Science.gov (United States)

    Hargadon, Kristian M

    2013-01-01

    Dendritic cells (DC) are key regulators of both innate and adaptive immunity, and the array of immunoregulatory functions exhibited by these cells is dictated by their differentiation, maturation, and activation status. Although a major role for these cells in the induction of immunity to pathogens has long been appreciated, data accumulated over the last several years has demonstrated that DC are also critical regulators of anti-tumor immune responses. However, despite the potential for stimulation of robust anti-tumor immunity by DC, tumor-altered DC function has been observed in many cancer patients and tumor-bearing animals and is often associated with tumor immune escape. Such dysfunction has significant implications for both the induction of natural anti-tumor immune responses as well as the efficacy of immunotherapeutic strategies that target endogenous DC in situ or that employ exogenous DC as part of anti-cancer immunization maneuvers. In this review, the major types of tumor-altered DC function will be described, with emphasis on recent insights into the mechanistic bases for the inhibition of DC differentiation from hematopoietic precursors, the altered programing of DC precursors to differentiate into myeloid-derived suppressor cells or tumor-associated macrophages, the suppression of DC maturation and activation, and the induction of immunoregulatory DC by tumors, tumor-derived factors, and tumor-associated cells within the milieu of the tumor microenvironment. The impact of these tumor-altered cells on the quality of the overall anti-tumor immune response will also be discussed. Finally, this review will also highlight questions concerning tumor-altered DC function that remain unanswered, and it will address factors that have limited advances in the study of this phenomenon in order to focus future research efforts in the field on identifying strategies for interfering with tumor-associated DC dysfunction and improving DC-mediated anti-tumor immunity.

  8. Central muscarinic cholinergic activation alters interaction between splenic dendritic cell and CD4+CD25- T cells in experimental colitis.

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    Peris Munyaka

    Full Text Available The cholinergic anti-inflammatory pathway (CAP is based on vagus nerve (VN activity that regulates macrophage and dendritic cell responses in the spleen through alpha-7 nicotinic acetylcholine receptor (a7nAChR signaling. Inflammatory bowel disease (IBD patients present dysautonomia with decreased vagus nerve activity, dendritic cell and T cell over-activation. The aim of this study was to investigate whether central activation of the CAP alters the function of dendritic cells (DCs and sequential CD4+/CD25-T cell activation in the context of experimental colitis.The dinitrobenzene sulfonic acid model of experimental colitis in C57BL/6 mice was used. Central, intracerebroventricular infusion of the M1 muscarinic acetylcholine receptor agonist McN-A-343 was used to activate CAP and vagus nerve and/or splenic nerve transection were performed. In addition, the role of α7nAChR signaling and the NF-kB pathway was studied. Serum amyloid protein (SAP-A, colonic tissue cytokines, IL-12p70 and IL-23 in isolated splenic DCs, and cytokines levels in DC-CD4+CD25-T cell co-culture were determined.McN-A-343 treatment reduced colonic inflammation associated with decreased pro-inflammatory Th1/Th17 colonic and splenic cytokine secretion. Splenic DCs cytokine release was modulated through α7nAChR and the NF-kB signaling pathways. Cholinergic activation resulted in decreased CD4+CD25-T cell priming. The anti-inflammatory efficacy of central cholinergic activation was abolished in mice with vagotomy or splenic neurectomy.Suppression of splenic immune cell activation and altered interaction between DCs and T cells are important aspects of the beneficial effect of brain activation of the CAP in experimental colitis. These findings may lead to improved therapeutic strategies in the treatment of IBD.

  9. Melanoma-derived factors alter the maturation and activation of differentiated tissue-resident dendritic cells.

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    Hargadon, Kristian M; Bishop, Johnathan D; Brandt, John P; Hand, Zachary C; Ararso, Yonathan T; Forrest, Osric A

    2016-01-01

    Dendritic cells (DCs) are key regulators of host immunity that are capable of inducing either immune tolerance or activation. In addition to their well-characterized role in shaping immune responses to foreign pathogens, DCs are also known to be critical for the induction and maintenance of anti-tumor immune responses. Therefore, it is important to understand how tumors influence the function of DCs and the quality of immune responses they elicit. Although the majority of studies in this field to date have utilized either immortalized DC lines or DC populations that have been generated under artificial conditions from hematopoietic precursors in vitro, we wished to investigate how tumors impact the function of already differentiated, tissue-resident DCs. Therefore, we used both an ex vivo and in vivo model system to assess the influence of melanoma-derived factors on DC maturation and activation. In ex vivo studies with freshly isolated splenic DCs, we demonstrate that the extent to which DC maturation and activation are altered by these factors correlates with melanoma tumorigenicity, and we identify partial roles for tumor-derived transforming growth factor (TGF)β1 and vascular endothelial growth factor (VEGF)-A in the altered functionality of DCs. In vivo studies using a lung metastasis model of melanoma also demonstrate tumorigenicity-dependent alterations to the function of lung-resident DCs, and skewed production of proinflammatory cytokines and chemokines by these tumor-altered cells is associated with recruitment of an immune infiltrate that may ultimately favor tumor immune escape and outgrowth.

  10. Dendritic cell vaccines.

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    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.

  11. Alterations in gene array patterns in dendritic cells from aged humans.

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    Jia-ning Cao

    Full Text Available Dendritic cells (DCs are major antigen-presenting cells that play a key role in initiating and regulating innate and adaptive immune responses. DCs are critical mediators of tolerance and immunity. The functional properties of DCs decline with age. The purpose of this study was to define the age-associated molecular changes in DCs by gene array analysis using Affymatrix GeneChips. The expression levels of a total of 260 genes (1.8% were significantly different (144 down-regulated and 116 upregulated in monocyte-derived DCs (MoDCs from aged compared to young human donors. Of the 260 differentially expressed genes, 24% were down-regulated by more than 3-fold, suggesting that a large reduction in expression occurred for a notable number of genes in the aged. Our results suggest that the genes involved in immune response to pathogens, cell migration and T cell priming display significant age-related changes. Furthermore, downregulated genes involved in cell cycle arrest and DNA replication may play a critical role in aging-associated genetic instability. These changes in gene expression provide molecular based evidence for age-associated functional abnormalities in human DCs that may be responsible for the defects in adaptive immunity observed in the elderly.

  12. Altered distribution of peripheral blood dendritic cell subsets in patients with pulmonary paracoccidioidomycosis.

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    Venturini, James; Cavalcante, Ricardo Souza; Moris, Daniela Vanessa; Golim, Márjorie de Assis; Levorato, Adriele Dandara; Reis, Karoline Hagatha Dos; Arruda, Maria Sueli Parreira de; Mendes, Rinaldo Poncio

    2017-09-01

    Paracoccidioidomycosis (PCM) is a systemic mycosis caused by fungi from the genus Paracoccidioides in Latin America. PCM-patients (PCM-p) are classified as having acute/subacute or chronic (CF) clinical forms. CF is responsible for 75%-90% of all cases, affects mainly adults over 30 years old and the clinical manifestation are associated mainly with lungs and mucosa of upper airdigestive tract. In addition, the CF patients exhibit fibrosis of the lungs, oral mucous membranes and adrenals, and pulmonary emphysema. Consequently, CF PCM-p with active disease, as well as those that have been apparently cured, seem to be an interesting model for studies aiming to understand the long-term host-fungi relationship and hypoxia. Dendritic cells (DCs) constitute a system that serve as a major link between innate and adaptive immunity composed of several subpopulations of cells including two main subsets: myeloid (mDCs) and plasmacytoid (pDCs). The present study aimed to access the distribution of PBDC subsets of CF PCM-p who were not treated (NT) or treated (apparently cured - AC). CF PCM-p were categorized into two groups, consisting of 9 NTs and 9 ACs. Twenty-one healthy individuals were used as the control group. The determination of the PBDC subsets was performed by FACS (fluorescence-activated cell sorting) and the dosage of serum TNF-α, IL1β, IL-18, CCL3, IL-10 and basic fibroblast growth factor (bFGF) by ELISA (enzyme-linked immunosorbent assay). A high count and percentage of mDCs was observed before treatment, along with a low count of pDCs in treated patients. Furthermore, the mDC:pDC ratio and serum levels of TNF-α was higher in both of the PCM-p groups than in the control group. In conclusion, our findings demonstrated that active PCM influences the distribution of mDCs and pDCs, and after treatment, PCM-p retained a lower count of pDCs associated with pro-inflammatory profile. Therefore, we identified new evidences of persistent immunological abnormalities in

  13. Dendritic cell neoplasms: an overview.

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    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.

  14. Proteome analysis demonstrates profound alterations in human dendritic cell nature by TX527, an analogue of vitamin D

    DEFF Research Database (Denmark)

    Ferreira, G. B.; van Etten, E.; Lage, K.

    2009-01-01

    Structural analogues of vitamin D have been put forward as therapeutic agents able to exploit the immunomodulatory effects of vitamin D, without its undesired calcemic side effects. We have demonstrated that TX527 affects dendritic cell (DC) maturation in vitro, resulting in the generation...

  15. Lack of NMDA receptor subunit exchange alters Purkinje cell dendritic morphology in cerebellar slice cultures

    NARCIS (Netherlands)

    Metzger, F; Pieri, [No Value; Eisel, ULM; Pieri, Isabelle

    2005-01-01

    Early postnatal developmental changes in N-methyl-D-aspartate (NMDA) receptor (NR) subunits regulate cerebellar granule cell maturation and potentially Purkinje cell development. We therefore investigated Purkinje cell morphology in slice cultures from mice with genetic subunit exchange from NR2C to

  16. CCR7 Modulates the Generation of Thymic Regulatory T Cells by Altering the Composition of the Thymic Dendritic Cell Compartment

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    Zicheng Hu

    2017-10-01

    Full Text Available Upon recognition of auto-antigens, thymocytes are negatively selected or diverted to a regulatory T cell (Treg fate. CCR7 is required for negative selection of auto-reactive thymocytes in the thymic medulla. Here, we describe an unanticipated contribution of CCR7 to intrathymic Treg generation. Ccr7−/− mice have increased Treg cellularity because of a hematopoietic but non-T cell autonomous CCR7 function. CCR7 expression by thymic dendritic cells (DCs promotes survival of mature Sirpα− DCs. Thus, CCR7 deficiency results in apoptosis of Sirpα− DCs, which is counterbalanced by expansion of immature Sirpα+ DCs that efficiently induce Treg generation. CCR7 deficiency results in enhanced intrathymic generation of Tregs at the neonatal stage and in lymphopenic adults, when Treg differentiation is critical for establishing self-tolerance. Together, these results reveal a complex function for CCR7 in thymic tolerance induction, where CCR7 not only promotes negative selection but also governs intrathymic Treg generation via non-thymocyte intrinsic mechanisms.

  17. Single-cell genetic expression of mutant GABAA receptors causing Human genetic epilepsy alters dendritic spine and GABAergic bouton formation in a mutation-specific manner

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    Pamela eLachance-Touchette

    2014-10-01

    Full Text Available Mutations in genes encoding for GABAA receptor subunits is a well-established cause of genetic generalized epilepsy. GABA neurotransmission is implicated in several developmental processes including neurite outgrowth and synapse formation. Alteration in excitatory/inhibitory synaptic activities plays a critical role in epilepsy, thus here we investigated whether mutations in α1 subunit of GABAA receptor may affect dendritic spine and GABAergic bouton formation. In particular, we examined the effects of three mutations of the GABRA1 gene (D219N, A322D and K353delins18X that were found in a cohort of families with genetic generalized epilepsy. We used a novel single-cell genetic approach, by preparing cortical organotypic cultures from GABRA1flox/flox mice and simultaneously inactivating endogenous GABRA1 and transfecting mutant α1 subunits in single glutamatergic pyramidal cells and basket GABAergic interneurons by biolistic transfection. We found that GABRA1-/- GABAergic cells showed reduced innervation field, which was rescued by co-expressing α1-A322D and α1-WT but not α1-D219N. We further found that the expression of the most severe GABRA1 missense mutation (α1-A322D induced a striking increase of spine density in pyramidal cells along with an increase in the number of mushroom-like spines. In addition, α1-A322D expression in GABAergic cells slightly increased perisomatic bouton density, whereas other mutations did not alter bouton formation. All together, these results suggest that the effects of different GABAAR mutations on GABAergic bouton and dendritic spine formation are specific to the mutation and cannot be always explained by a simple loss-of-function gene model. The use of single cell genetic manipulation in organotypic cultures may provide a better understanding of the specific and distinct neural circuit alterations caused by different GABAA receptor subunit mutations and will help define the pathophysiology of genetic

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

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    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.

  19. Fast generation of dendritic cells

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

    2009-01-01

    Dendritic cells (DC) are potent antigen presenting cells capable of inducing immune responses. DC are widely used as vaccine adjuvant in experimental clinical settings. DC-based vaccines are normally generated using a standard 8day DC protocol (SDDC). In attempts to shorten the vaccine production...... 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....

  20. Targeting vaccines to dendritic cells

    DEFF Research Database (Denmark)

    Foged, Camilla; Sundblad, Anne; Hovgaard, Lars

    2002-01-01

    Dendritic cells (DC) are specialized antigen presenting cells (APC) with a remarkable ability to take up antigens and stimulate major histocompatibility complex (MHC)-restricted specific immune responses. Recent discoveries have shown that their role in initiating primary immune responses seems...... to be far superior to that of B-cells and macrophages. DC are localized at strategic places in the body at sites used by pathogens to enter the organism, and are thereby in an optimal position to capture antigens. In general, vaccination strategies try to mimic the invasiveness of the pathogens. DC...

  1. Dendritic Cell-Targeted Vaccines

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    Cohn, Lillian; Delamarre, Lélia

    2014-01-01

    Despite significant effort, the development of effective vaccines inducing strong and durable T-cell responses against intracellular pathogens and cancer cells has remained a challenge. The initiation of effector CD8+ T-cell responses requires the presentation of peptides derived from internalized antigen on class I major histocompatibility complex molecules by dendritic cells (DCs) in a process called cross-presentation. A current strategy to enhance the effectiveness of vaccination is to deliver antigens directly to DCs. This is done via selective targeting of antigen using monoclonal antibodies directed against endocytic receptors on the surface of the DCs. In this review, we will discuss considerations relevant to the design of such vaccines: the existence of DC subsets with specialized functions, the impact of the antigen intracellular trafficking on cross-presentation, and the influence of maturation signals received by DCs on the outcome of the immune response. PMID:24910635

  2. Gut dendritic cell activation links an altered colonic microbiome to mucosal and systemic T-cell activation in untreated HIV-1 infection.

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    Dillon, S M; Lee, E J; Kotter, C V; Austin, G L; Gianella, S; Siewe, B; Smith, D M; Landay, A L; McManus, M C; Robertson, C E; Frank, D N; McCarter, M D; Wilson, C C

    2016-01-01

    HIV-1-associated disruption of intestinal homeostasis is a major factor contributing to chronic immune activation and inflammation. Dendritic cells (DCs) are crucial in maintaining intestinal homeostasis, but the impact of HIV-1 infection on intestinal DC number and function has not been extensively studied. We compared the frequency and activation/maturation status of colonic myeloid DC (mDC) subsets (CD1c(+) and CD1c(neg)) and plasmacytoid DCs in untreated HIV-1-infected subjects with uninfected controls. Colonic mDCs in HIV-1-infected subjects had increased CD40 but decreased CD83 expression, and CD40 expression on CD1c(+) mDCs positively correlated with mucosal HIV-1 viral load, with mucosal and systemic cytokine production, and with frequencies of activated colon and blood T cells. Percentage of CD83(+)CD1c(+) mDCs negatively correlated with frequencies of interferon-γ-producing colon CD4(+) and CD8(+) T cells. CD40 expression on CD1c(+) mDCs positively associated with abundance of high prevalence mucosal Prevotella copri and Prevotella stercorea but negatively associated with a number of low prevalence mucosal species, including Rumminococcus bromii. CD1c(+) mDC cytokine production was greater in response to in vitro stimulation with Prevotella species relative to R. bromii. These findings suggest that, during HIV infection, colonic mDCs become activated upon exposure to mucosal pathobiont bacteria leading to mucosal and systemic immune activation.

  3. Gut Dendritic Cell Activation Links an Altered Colonic Microbiome to Mucosal and Systemic T Cell Activation in Untreated HIV-1 infection

    Science.gov (United States)

    Dillon, SM; Lee, EJ; Kotter, CV; Austin, GL; Gianella, S; Siewe, B; Smith, DM; Landay, AL; McManus, MC; Robertson, CE; Frank, DN; McCarter, MD; Wilson, CC

    2015-01-01

    HIV-1-associated disruption of intestinal homeostasis is a major factor contributing to chronic immune activation and inflammation. Dendritic cells (DCs) are crucial in maintaining intestinal homeostasis, but the impact of HIV-1 infection on intestinal DC number and function has not been extensively studied. We compared the frequency and activation/maturation status of colonic myeloid DC (mDC) subsets (CD1c+ and CD1cneg) and plasmacytoid DCs in untreated HIV-1-infected subjects with uninfected controls. Colonic mDCs in HIV-1-infected subjects had increased CD40 but decreased CD83 expression, and CD40 expression on CD1c+ mDCs positively correlated with mucosal HIV-1 viral load, with mucosal and systemic cytokine production, and with frequencies of activated colon and blood T cells. Percent of CD83+CD1c+ mDCs negatively correlated with frequencies of IFN-γ-producing colon CD4+ and CD8+ T cells. CD40 expression on CD1c+ mDCs positively associated with abundance of high prevalence mucosal Prevotella copri and P. stercorea, but negatively associated with a number of low prevalence mucosal species including Rumminococcus bromii. CD1c+ mDC cytokine production was greater in response to in vitro stimulation with Prevotella species relative to R. bromii. These findings suggest that during HIV infection, colonic mDCs become activated upon exposure to mucosal pathobiont bacteria leading to mucosal and systemic immune activation. PMID:25921339

  4. A cell adhesion molecule mimetic, FGL peptide, induces alterations in synapse and dendritic spine structure in the dentate gyrus of aged rats: a three-dimensional ultrastructural study

    DEFF Research Database (Denmark)

    Popov, Victor I; Medvedev, Nikolay I; Kraev, Igor V

    2008-01-01

    The FGL peptide is a neural cell adhesion molecule (NCAM) mimetic comprising a 15-amino-acid-long sequence of the FG loop region of the second fibronectin type III module of NCAM. It corresponds to the binding site of NCAM for the fibroblast growth factor receptor 1. FGL improves cognitive function...... through enhancement of synaptic function. We examined the effect of FGL on synaptic and dendritic structure in the brains of aged (22-month-old) rats that were injected subcutaneously (8 mg/kg) at 2-day intervals until 19 days after the start of the experiment. Animals were perfused with fixative, brains...... structure of synapses and dendritic spines in hippocampus of aged rats, complementing data showing its effect on cognitive processes....

  5. Dendritic cells in autoimmune thyroid disease.

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    Kabel, P J; Voorbij, H A; van der Gaag, R D; Wiersinga, W M; de Haan, M; Drexhage, H A

    1987-01-01

    Dendritic cells form a morphologically distinct class of cells characterized by shape, reniform nucleus, absent to weak acid-phosphatase activity and strong Class II MHC determinant positivity. Functionally they are the most efficient cells in antigen presentation to T-lymphocytes which indicates their role in the initiation of an immune response. Using immunehistochemical techniques we studied the presence of dendritic cells in normal Wistar rat and human thyroids, in thyroids of BBW rats developing thyroid autoimmunity and in Graves' goitres. Dendritic cells could be identified in all thyroids studied and were positioned underneath the thyrocytes in between the follicles. Skin dendritic cells travel via lymphatics to draining lymph nodes, thus forming an antigen presenting cell system. It is likely that a similar cell system exists on the level of the thyroid for dendritic cells have also been detected in thyroid draining lymph nodes. In normal thyroid tissue of both human and rat dendritic cells were relatively scarce. During the initial phases of the thyroid autoimmune response in the BBW rat (before the appearance of Tg-antibodies in the circulation) numbers of thyroid dendritic cells increased. Intrathyroidal T-helper cells, B-cells or plasma cells could not be found. The thyroid draining lymph node contained large numbers of plasma cells. During the later stages of the thyroid autoimmune response in the BB/W rat (after the appearance of Tg-antibodies in the circulation) and in Graves' goitres dendritic cells were not only present in high number, but 20-30% were seen in contact with now-present intrathyroidal T-helper lymphocytes.(ABSTRACT TRUNCATED AT 250 WORDS)

  6. Dendritic cells and aging: consequences for autoimmunity.

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    Agrawal, Anshu; Sridharan, Aishwarya; Prakash, Sangeetha; Agrawal, Harsh

    2012-01-01

    The immune system has evolved to mount immune responses against foreign pathogens and to remain silent against self-antigens. A balance between immunity and tolerance is required as any disturbance may result in chronic inflammation or autoimmunity. Dendritic cells (DCs) actively participate in maintaining this balance. Under steady-state conditions, DCs remain in an immature state and do not mount an immune response against circulating self-antigens in the periphery, which maintains a state of tolerance. By contrast, foreign antigens result in DC maturation and DC-induced T-cell activation. Inappropriate maturation of DCs due to infections or tissue injury may cause alterations in the balance between the tolerogenic and immunogenic functions of DCs and instigate the development of autoimmune diseases. This article provides an overview of the effects of advancing age on DC functions and their implications in autoimmunity.

  7. The dendritic cell niche in chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Haczku Angela

    2012-09-01

    Full Text Available Abstract The pulmonary innate immune system is heavily implicated in the perpetual airway inflammation and impaired host defense characterizing Chronic Obstructive Pulmonary Disease (COPD. The airways of patients suffering from COPD are infiltrated by various immune and inflammatory cells including macrophages, neutrophils, T lymphocytes, and dendritic cells. While the role of macrophages, neutrophils and T lymphocytes is well characterized, the contribution of dendritic cells to COPD pathogenesis is still the subject of emerging research. A paper by Botelho and colleagues in the current issue of Respiratory Research investigates the importance of dendritic cell recruitment in cigarette-smoke induced acute and chronic inflammation in mice. Dendritic cells of the healthy lung parenchyma and airways perform an important sentinel function and regulate immune homeostasis. During inflammatory responses the function and migration pattern of these cells is dramatically altered but the underlying mechanisms are incompletely understood. Botelho and colleagues demonstrate here the importance of IL-1R1/IL-1α related mechanisms including CCL20 production in cigarette-smoke induced recruitment of dendritic cells and T cell activation in the mouse lung.

  8. 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.

  9. [Natural killer cells complot with dendritic cells].

    Science.gov (United States)

    Bielawska-Pohl, Aleksandra; Pajtasz-Piasecka, Elżbieta; Duś, Danuta

    2013-03-18

    Dendritic cells (DC) were initially considered as antigen presenting cells participating in the polarization of the immune response. Further understanding of their biology allowed determining their additional functions such as immunoregulatory and cytotoxicity. Until recently natural killer (NK) cells were known as a homogeneous population of lymphocytes capable of non-specific recognizing and eliminating target cells. Now it is widely accepted that NK cells, as a heterogeneous population, may also possess immunomodulatory functions. Moreover, the most recent analysis of the interactions between DC and NK cells revealed the exceptional functions of these cells. As a result of these studies the existence of bitypic cell population was postulated. The distinguishing features of these hybrid cells are: the expression of surface receptors typical for NK cells and DC, the cytotoxic activity, the production of interferons as well as their ability to present antigen after prior stimulation. Despite the lack of strong direct evidence that the same cell can be both cytotoxic and effectively present the antigen at the same time, there are experimental findings suggesting that generated ex vivo bitypic cells may be used in antitumor therapy. 

  10. 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...

  11. Ins and outs of dendritic cells.

    NARCIS (Netherlands)

    Schuurhuis, D.H.; Fu, N.; Ossendorp, F.; Melief, C.J.

    2006-01-01

    Dendritic cells (DC) are professional antigen-presenting cells which are strategically positioned at the boundaries between the inner and the outside world, in this way bridging innate and adaptive immunity. DC can initiate T cell responses against microbial pathogens and tumors due to their

  12. Nonuniform alteration of dendritic development in the cerebral cortex following prenatal cocaine exposure.

    Science.gov (United States)

    Jones, L; Fischer, I; Levitt, P

    1996-01-01

    Prenatal exposure to cocaine has the potential to modify normal brain development and result in behavioral dysfunction. We used a new animal model in which cocaine was administered intravenously during prenatal development in pregnant rabbits twice daily at low dosages. Analysis of brain development focused on two areas of the cerebral cortex, anterior cingulate and primary visual, in which dopamine afferents, a target of cocaine, are differentially distributed. All postnatal rabbits exposed to cocaine prenatally exhibited normal features of cortical organization, including thickness, lamination patterns, and cytoarchitectonic differentiation. General axonal and astroglial organization, assessed by neurofilament-H and glial fibrillary acidic protein immunostaining, also was unchanged in the cocaine-exposed animals. Analysis of dendritic organization was done using antibodies against microtubule-associated protein 2 (MAP2), which reveals mostly the larger apical shafts of cortical pyramidal cells. In the anterior cingulate cortex of adolescent rabbits exposed to cocaine in utero, there is a marked decrease in both dendritic bundling and typical long, straight MAP2-stained profiles. In normal animals, the long, bundled dendrites area readily traced in a single focal plane from layer III or V pyramidal cell somata to the pial surface in saline-treated animals. Instead, the drug-exposed animals contained many more short segments of MAP2-stained dendrites that could be viewed coursing in and out of the plane of focus in the sections. Apical dendrites in mature visual cortex appeared normal in the cocaine-exposed rabbits. Examination of MAP2 staining at various postnatal ages revealed that the dendritic changes expressed in the adolescent anterior cingulate cortex appeared less robust, but still evident at birth. By P10-14, dendritic modifications were similar to the adult. Counts of the number of MAP2-positive dendritic profiles crossing the layer II-III interface

  13. Maximizing dendritic cell migration in cancer immunotherapy

    NARCIS (Netherlands)

    Verdijk, Pauline; Aarntzen, Erik H. J. G.; Punt, Cornelis J. A.; de Vries, I. Jolanda M.; Figdor, Carl G.

    2008-01-01

    The success of dendritic cell (DC)-based immunotherapy in inducing cellular immunity against tumors is highly dependent on accurate delivery and trafficking of the DC to T-cell-rich areas of secondary lymphoid tissues. To provide an overview of DC migration in vivo and how migration to peripheral

  14. Maximizing dendritic cell migration in cancer immunotherapy.

    NARCIS (Netherlands)

    Verdijk, P.; Aarntzen, E.H.J.G.; Punt, C.J.A.; Vries, I.J.M. de; Figdor, C.G.

    2008-01-01

    BACKGROUND: The success of dendritic cell (DC)-based immunotherapy in inducing cellular immunity against tumors is highly dependent on accurate delivery and trafficking of the DC to T-cell-rich areas of secondary lymphoid tissues. OBJECTIVE: To provide an overview of DC migration in vivo and how

  15. 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’

  16. Molecular characterization of interdigitating dendritic cell sarcoma

    Directory of Open Access Journals (Sweden)

    Glen J. Weiss

    2010-08-01

    Full Text Available Interdigitating dendritic cell sarcoma is an extremely rare cancer that lacks a standard treatment approach. We report on a patient who was surgically resected and remains disease-free. The tumor was assessed for druggable targets using immunohistochemical staining to identify potential agents that could be used in the event of disease recurrence.

  17. Characterization of chicken dendritic cell markers

    Science.gov (United States)

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

  18. 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

  19. 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...

  20. Histamine receptor 2 modifies dendritic cell responses to microbial ligands.

    Science.gov (United States)

    Frei, Remo; Ferstl, Ruth; Konieczna, Patrycja; Ziegler, Mario; Simon, Tunde; Rugeles, Tulia Mateus; Mailand, Susanne; Watanabe, Takeshi; Lauener, Roger; Akdis, Cezmi A; O'Mahony, Liam

    2013-07-01

    The induction of tolerance and protective immunity to microbes is significantly influenced by host- and microbiota-derived metabolites, such as histamine. We sought to identify the molecular mechanisms for histamine-mediated modulation of pattern recognition receptor signaling. Human monocyte-derived dendritic cells (MDDCs), myeloid dendritic cells, and plasmacytoid dendritic cells were examined. Cytokine secretion, gene expression, and transcription factor activation were measured after stimulation with microbial ligands and histamine. Histamine receptor 2 (H₂R)-deficient mice, histamine receptors, and their signaling pathways were investigated. Histamine suppressed MDDC chemokine and proinflammatory cytokine secretion, nuclear factor κB and activator protein 1 activation, mitogen-activated protein kinase phosphorylation, and T(H)1 polarization of naive lymphocytes, whereas IL-10 secretion was enhanced in response to LPS and Pam3Cys. Histamine also suppressed LPS-induced myeloid dendritic cell TNF-α secretion and suppressed CpG-induced plasmacytoid dendritic cell IFN-α gene expression. H₂R signaling through cyclic AMP and exchange protein directly activated by cyclic AMP was required for the histamine effect on LPS-induced MDDC responses. Lactobacillus rhamnosus, which secretes histamine, significantly suppressed Peyer patch IL-2, IL-4, IL-5, IL-12, TNF-α, and GM-CSF secretion in wild-type but not H₂R-deficient animals. Both host- and microbiota-derived histamine significantly alter the innate immune response to microbes through H₂R. Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  1. Dendritic Cells as Danger-Recognizing Biosensors

    Directory of Open Access Journals (Sweden)

    Seokmann Hong

    2009-08-01

    Full Text Available Dendritic cells (DCs are antigen presenting cells that are characterized by a potent capacity to initiate immune responses. DCs comprise several subsets with distinct phenotypes. After sensing any danger(s to the host via their innate immune receptors such as Toll-like receptors, DCs become mature and subsequently present antigens to CD4+ T cells. Since DCs possess the intrinsic capacity to polarize CD4+ helper cells, it is critical to understand the immunological roles of DCs for clinical applications. Here, we review the different DC subsets, their danger-sensing receptors and immunological functions. Furthermore, the cytokine reporter mouse model for studying DC activation is introduced.

  2. 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.

  3. Dendritic spread and functional coverage of starburst amacrine cells.

    Science.gov (United States)

    Keeley, Patrick W; Whitney, Irene E; Raven, Mary A; Reese, Benjamin E

    2007-12-10

    The network of starburst amacrine cells plays a fundamental role in the neural circuitry underlying directional selectivity within the retina. Individual sectors of the starburst dendritic field are directionally selective by virtue of a mutually inhibitory relationship between starburst amacrine cells with overlapping dendrites. These features of the starburst amacrine cell network suggest that starburst cells regulate their dendritic overlap to ensure a uniform coverage of the retinal surface. The present study has compared the dendritic morphology of starburst amacrine cells in two different strains of mice that differ in starburst amacrine cell number. The A/J (A) strain contains about one-quarter fewer starburst amacrine cells than does the C57BL/6J (B6) strain, although the mosaics of starburst amacrine cells in both strains are comparably patterned. Dendritic field size, however, does not compensate for the difference in density, the A strain having a slightly smaller dendritic field relative to the B6 strain, yielding a significantly larger dendritic coverage factor for individual cells in the B6 strain. The area of the distal (output) annulus of the dendritic field occupies a comparable proportion of the overall field area in the two strains, but overlapping annuli establish a finer meshwork of co-fasciculating processes in the B6 strain. These results would suggest that the architecture of the dendritic network, rather than the overall size of the dendritic field, is dependent on the density of starburst amacrine cells. (c) 2007 Wiley-Liss, Inc.

  4. 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...... 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....

  5. [Dendritic cells in cancer immunotherapy].

    Science.gov (United States)

    Gato, M; Liechtenstein, T; Blanco-Luquín, I; Zudaire, M I; Kochan, G; Escors, D

    2015-01-01

    Since the beginning of the 20th century, biomedical scientists have tried to take advantage of the natural anti-cancer activities of the immune system. However, all the scientific and medical efforts dedicated to this have not resulted in the expected success. In fact, classical antineoplastic treatments such as surgery, radio and chemotherapy are still first line treatments. Even so, there is a quantity of experimental evidence demonstrating that cancer cells are immunogenic. However, the effective activation of anti-cancer T cell responses closely depends on an efficient antigen presentation carried out by professional antigen presenting cells such as DC. Although there are a number of strategies to strengthen antigen presentation by DC, anti-cancer immunotherapy is not as effective as we would expect according to preclinical data accumulated in recent decades. We do not aim to make an exhaustive review of DC immunotherapy here, which is an extensive research subject already dealt with in many specialised reviews. Instead, we present the experimental approaches undertaken by our group over the last decade, by modifying DC to improve their anti-tumour capacities.

  6. Targeting vaccines to dendritic cells

    DEFF Research Database (Denmark)

    Foged, Camilla; Sundblad, Anne; Hovgaard, Lars

    2002-01-01

    are considered to play a central role for the provocation of primary immune responses by vaccination. A rational way of improving the potency and safety of new and already existing vaccines could therefore be to direct vaccines specifically to DC. There is a need for developing multifunctional vaccine drug...... 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...... 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....

  7. Targeting dendritic cells--why bother?

    Science.gov (United States)

    Kreutz, Martin; Tacken, Paul J; Figdor, Carl G

    2013-04-11

    Vaccination is among the most efficient forms of immunotherapy. Although sometimes inducing lifelong protective B-cell responses, T-cell-mediated immunity remains challenging. Targeting antigen to dendritic cells (DCs) is an extensively explored concept aimed at improving cellular immunity. The identification of various DC subsets with distinct functional characteristics now allows for the fine-tuning of targeting strategies. Although some of these DC subsets are regarded as superior for (cross-) priming of naive T cells, controversies still remain about which subset represents the best target for immunotherapy. Because targeting the antigen alone may not be sufficient to obtain effective T-cell responses, delivery systems have been developed to target multiple vaccine components to DCs. In this Perspective, we discuss the pros and cons of targeting DCs: if targeting is beneficial at all and which vaccine vehicles and immunization routes represent promising strategies to reach and activate DCs.

  8. 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.

  9. Homophilic Protocadherin Cell-Cell Interactions Promote Dendrite Complexity

    Directory of Open Access Journals (Sweden)

    Michael J. Molumby

    2016-05-01

    Full Text Available Growth of a properly complex dendrite arbor is a key step in neuronal differentiation and a prerequisite for neural circuit formation. Diverse cell surface molecules, such as the clustered protocadherins (Pcdhs, have long been proposed to regulate circuit formation through specific cell-cell interactions. Here, using transgenic and conditional knockout mice to manipulate γ-Pcdh repertoire in the cerebral cortex, we show that the complexity of a neuron’s dendritic arbor is determined by homophilic interactions with other cells. Neurons expressing only one of the 22 γ-Pcdhs can exhibit either exuberant or minimal dendrite complexity, depending only on whether surrounding cells express the same isoform. Furthermore, loss of astrocytic γ-Pcdhs, or disruption of astrocyte-neuron homophilic matching, reduces dendrite complexity cell non-autonomously. Our data indicate that γ-Pcdhs act locally to promote dendrite arborization via homophilic matching, and they confirm that connectivity in vivo depends on molecular interactions between neurons and between neurons and astrocytes.

  10. 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

  11. 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.

  12. 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...

  13. 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

  14. Dendritic Properties Control Energy Efficiency of Action Potentials in Cortical Pyramidal Cells.

    Science.gov (United States)

    Yi, Guosheng; Wang, Jiang; Wei, Xile; Deng, Bin

    2017-01-01

    Neural computation is performed by transforming input signals into sequences of action potentials (APs), which is metabolically expensive and limited by the energy available to the brain. The metabolic efficiency of single AP has important consequences for the computational power of the cell, which is determined by its biophysical properties and morphologies. Here we adopt biophysically-based two-compartment models to investigate how dendrites affect energy efficiency of APs in cortical pyramidal neurons. We measure the Na + entry during the spike and examine how it is efficiently used for generating AP depolarization. We show that increasing the proportion of dendritic area or coupling conductance between two chambers decreases Na + entry efficiency of somatic AP. Activating inward Ca 2+ current in dendrites results in dendritic spike, which increases AP efficiency. Activating Ca 2+ -activated outward K + current in dendrites, however, decreases Na + entry efficiency. We demonstrate that the active and passive dendrites take effects by altering the overlap between Na + influx and internal current flowing from soma to dendrite. We explain a fundamental link between dendritic properties and AP efficiency, which is essential to interpret how neural computation consumes metabolic energy and how biophysics and morphologies contribute to such consumption.

  15. 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

  16. Time course of EPSCs in ON‐type starburst amacrine cells is independent of dendritic location

    Science.gov (United States)

    Stincic, Todd; Smith, Robert G.

    2016-01-01

    Key points Direction selectivity has been widely studied as an example of a complex neural computation.Directional GABA release from starburst amacrine cells (SBACs) is critical for generating directional signals in direction‐selective ganglion cells. The mechanisms producing the directional release remain unclear.For SBACs, ordered distribution of sustained and transient bipolar cell inputs along the dendrites is proposed to generate directional GABA release. This study tests whether this hypothesis applies to ON‐type SBACs.EPSCs activated at proximal and distal dendritic locations have the same time course. Therefore, the ordered arrangement of inputs from bipolar cells with different kinetic properties cannot be responsible for generating directional GABA release from ON‐type SBACs. Abstract Direction selectivity in the retina relies critically on directionally asymmetric GABA release from the dendritic tips of starburst amacrine cells (SBACs). GABA release from each radially directed dendrite is larger for motion outward from the soma toward the dendritic tips than for motion inwards toward the soma. The biophysical mechanisms generating these directional signals remain controversial. A model based on electron‐microscopic reconstructions of the mouse retina proposed that an ordered arrangement of kinetically distinct bipolar cell inputs to ON‐ and OFF‐type SBACs could produce directional GABA release. We tested this prediction by measuring the time course of EPSCs in ON‐type SBACs in the mouse retina, activated by proximal and distal light stimulation. Contrary to the prediction, the kinetics of the excitatory inputs were independent of dendritic location. Computer simulations based on 3D reconstructions of SBAC dendrites demonstrated that the response kinetics of distal inputs were not significantly altered by dendritic filtering. These direct physiological measurements, do not support the hypothesis that directional signals in SBACs arise from

  17. Time course of EPSCs in ON-type starburst amacrine cells is independent of dendritic location.

    Science.gov (United States)

    Stincic, Todd; Smith, Robert G; Taylor, W Rowland

    2016-10-01

    Direction selectivity has been widely studied as an example of a complex neural computation. Directional GABA release from starburst amacrine cells (SBACs) is critical for generating directional signals in direction-selective ganglion cells. The mechanisms producing the directional release remain unclear. For SBACs, ordered distribution of sustained and transient bipolar cell inputs along the dendrites is proposed to generate directional GABA release. This study tests whether this hypothesis applies to ON-type SBACs. EPSCs activated at proximal and distal dendritic locations have the same time course. Therefore, the ordered arrangement of inputs from bipolar cells with different kinetic properties cannot be responsible for generating directional GABA release from ON-type SBACs. Direction selectivity in the retina relies critically on directionally asymmetric GABA release from the dendritic tips of starburst amacrine cells (SBACs). GABA release from each radially directed dendrite is larger for motion outward from the soma toward the dendritic tips than for motion inwards toward the soma. The biophysical mechanisms generating these directional signals remain controversial. A model based on electron-microscopic reconstructions of the mouse retina proposed that an ordered arrangement of kinetically distinct bipolar cell inputs to ON- and OFF-type SBACs could produce directional GABA release. We tested this prediction by measuring the time course of EPSCs in ON-type SBACs in the mouse retina, activated by proximal and distal light stimulation. Contrary to the prediction, the kinetics of the excitatory inputs were independent of dendritic location. Computer simulations based on 3D reconstructions of SBAC dendrites demonstrated that the response kinetics of distal inputs were not significantly altered by dendritic filtering. These direct physiological measurements, do not support the hypothesis that directional signals in SBACs arise from the ordered arrangement of

  18. 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.

  19. 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...

  20. 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...

  1. Dendritic Cells in the Cancer Microenvironment

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

    2013-01-01

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

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

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    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.

  3. Murine Cytomegalovirus Spreads by Dendritic Cell Recirculation

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    Helen E. Farrell

    2017-10-01

    Full Text Available Herpesviruses have coevolved with their hosts over hundreds of millions of years and exploit fundamental features of their biology. Cytomegaloviruses (CMVs colonize blood-borne myeloid cells, and it has been hypothesized that systemic dissemination arises from infected stem cells in bone marrow. However, poor CMV transfer by stem cell transplantation argues against this being the main reservoir. To identify alternative pathways for CMV spread, we tracked murine CMV (MCMV colonization after mucosal entry. We show that following intranasal MCMV infection, lung CD11c+ dendritic cells (DC migrated sequentially to lymph nodes (LN, blood, and then salivary glands. Replication-deficient virus followed the same route, and thus, DC infected peripherally traversed LN to enter the blood. Given that DC are thought to die locally following their arrival and integration into LN, recirculation into blood represents a new pathway. We examined host and viral factors that facilitated this LN traverse. We show that MCMV-infected DC exited LN by a distinct route to lymphocytes, entering high endothelial venules and bypassing the efferent lymph. LN exit required CD44 and the viral M33 chemokine receptor, without which infected DC accumulated in LN and systemic spread was greatly reduced. Taken together, our studies provide the first demonstration of virus-driven DC recirculation. As viruses follow host-defined pathways, high endothelial venules may normally allow DC to pass from LN back into blood.

  4. The dendritic cell niche in chronic obstructive pulmonary disease

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    Haczku, Angela

    2012-01-01

    Abstract The pulmonary innate immune system is heavily implicated in the perpetual airway inflammation and impaired host defense characterizing Chronic Obstructive Pulmonary Disease (COPD). The airways of patients suffering from COPD are infiltrated by various immune and inflammatory cells including macrophages, neutrophils, T lymphocytes, and dendritic cells. While the role of macrophages, neutrophils and T lymphocytes is well characterized, the contribution of dendritic cells to COPD pathog...

  5. Preconception paternal stress in rats alters dendritic morphology and connectivity in the brain of developing male and female offspring.

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    Harker, A; Raza, S; Williamson, K; Kolb, B; Gibb, R

    2015-09-10

    The goal of this research was to examine the effect of preconception paternal stress (PPS) on the subsequent neurodevelopment and behavior of male and female offspring. Prenatal (gestational) stress has been shown to alter brain morphology in the developing brain, and is presumed to be a factor in the development of some adult psychopathologies. Our hypothesis was that paternal stress in the preconception period could impact brain development in the offspring, leading to behavioral abnormalities later in life. The purpose of this study was to examine the effect of preconception paternal stress on developing male and female offspring brain morphology in five brain areas; medial prefrontal cortex (mPFC), orbitofrontal cortex (OFC), parietal cortex (Par1), hippocampus (CA1) and nucleus accumbens (NAc). Alterations in dendritic measures and spine density were observed in each brain area examined in paternal stress offspring. Our two main findings reveal; (1) PPS alters brain morphology and organization and these effects are different than the effects of stress observed at other ages; and, (2) the observed dendritic changes were sexually dimorphic. This study provides direct evidence that PPS modifies brain architecture in developing offspring, including dendritic length, cell complexity, and spine density. Alterations observed may contribute to the later development of psychopathologies and maladaptive behaviors in the offspring. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

  6. Histamine regulates murine primary dendritic cell functions.

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    Schenk, Heiko; Neumann, Detlef; Kloth, Christina

    2016-10-01

    The modulation of antigen uptake and activation of dendritic cells (DCs) by histamine may function as a regulator of inflammation. Therefore, we sought to determine the impact of histamine on antigen uptake by and activation of murine DCs. DCs from spleen and lung were either identified by flow cytometry or were immunomagnetically enriched. Cells were stimulated with histamine, and the regulation of MHC-II and co-stimulatory molecule expression (CD80, CD86, and ICOS-L) and antigen uptake were quantified by flow cytometry. Individual contributions of the histamine receptor subtypes were determined by using the antagonists mepyramine (histamine H1-receptor: H1R), famotidine (H2R), and JNJ 7777120 (H4R). Histamine accelerated the uptake of soluble antigen via the H1R, H2R, and H4R in splenic DCs. Co-stimulatory molecule expression was enhanced already by enrichment procedures, thus, the analyses were performed in unseparated cell populations. Histamine enhanced the expression of CD86 and ICOS-L while expression of CD80 was unaffected. Antagonism at H1R, H2R, and H4R and at H1R and H4R reduced the histamine-induced enhanced expression of CD86 and ICOS-L, respectively. Histamine contributes to the regulation of the immunological synapse by stimulation of antigen uptake and activation of DCs via H1R, H2R, and H4R.

  7. Use and abuse of dendritic cells by Toxoplasma gondii

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    Sanecka, Anna; Frickel, Eva-Maria

    2012-01-01

    The ubiquitous apicomplexan parasite Toxoplasma gondii stimulates its host’s immune response to achieve quiescent chronic infection. Central to this goal are host dendritic cells. The parasite exploits dendritic cells to disseminate through the body, produce pro-inflammatory cytokines, present its antigens to the immune system and yet at the same time subvert their signaling pathways in order to evade detection. This carefully struck balance by Toxoplasma makes it the most successful parasite on this planet. Recent progress has highlighted specific parasite and host molecules that mediate some of these processes particularly in dendritic cells and in other cells of the innate immune system. Critically, there are several important factors that need to be taken into consideration when concluding how the dendritic cells and the immune system deal with a Toxoplasma infection, including the route of administration, parasite strain and host genotype. PMID:23221473

  8. Deciphering dendritic cell heterogenity in immunity

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    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.

  9. Dendritic spines form 'collars' in hippocampal granule cells.

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    Rusakov, D A; Stewart, M G; Sojka, M; Richter-Levin, G; Bliss, T V

    1995-07-31

    A quantitative study of the distribution of dendritic spines was carried out in three orders of dendritic branches of granule cells from the dentate gyrus of the rat hippocampus. Golgi-stained preparations (7-19 neurones in each of seven rats) were analysed using computerized microscopy. Identification of spines and quantification of stem-spine geometry was performed using a segmentation algorithm and a line skeleton transformation of dendritic images. Analysis of data using the statistics of point processes revealed that, in all three branch orders, the distribution of visible spines along dendrites was not evenly random, but included dense clusters of spines surrounding the dendritic stem (spine 'collars'). Three-dimensional reconstructions from serial ultrathin sections have confirmed the presence of such spine groups. We speculate the spine collars represent a functional element in which associative synaptic plasticity is fostered by the proximity of individual synapses.

  10. The chemoimmunotherapy based on dendritic cells and cisplatin in experiment

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    Gorbach, O.; Khranovska, N.; Skachkova, O.; Sydor, R.; Pozur, V.

    2014-01-01

    The aim of the study was to develop a scheme of combined chemoimmunotherapy and to investigate antitumor and immunomodulatory activity of chemoimmunotherapy regimen using the vaccine based on dendritic cells and low-doses of cisplatin in CBA mice with sarcoma-37. Maximal antitumor and immunomodulatory effects were observed after application of the vaccine based on dendritic cells in combination with doses of cisplatin concentration of 2 mg/kg. Among significant immunomodulatory effects of com...

  11. Functional Compartmentalization within Starburst Amacrine Cell Dendrites in the Retina

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    Alon Poleg-Polsky

    2018-03-01

    Full Text Available Summary: Dendrites in many neurons actively compute information. In retinal starburst amacrine cells, transformations from synaptic input to output occur within individual dendrites and mediate direction selectivity, but directional signal fidelity at individual synaptic outputs and correlated activity among neighboring outputs on starburst dendrites have not been examined systematically. Here, we record visually evoked calcium signals simultaneously at many individual synaptic outputs within single starburst amacrine cells in mouse retina. We measure visual receptive fields of individual output synapses and show that small groups of outputs are functionally compartmentalized within starburst dendrites, creating distinct computational units. Inhibition enhances compartmentalization and directional tuning of individual outputs but also decreases the signal-to-noise ratio. Simulations suggest, however, that the noise underlying output signal variability is well tolerated by postsynaptic direction-selective ganglion cells, which integrate convergent inputs to acquire reliable directional information. : Poleg-Polsky et al. examine the directional signaling fidelity of individual synapses on starburst amacrine cell dendrites. They identify functionally and morphologically distinct signaling compartments within SAC dendrites and show that inhibition enhances reliable decoding by postsynaptic direction-selective ganglion cells. Keywords: retina, synaptic transmission, amacrine cell, correlation, visual processing, inhibition, direction selectivity

  12. Functional Compartmentalization within Starburst Amacrine Cell Dendrites in the Retina.

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    Poleg-Polsky, Alon; Ding, Huayu; Diamond, Jeffrey S

    2018-03-13

    Dendrites in many neurons actively compute information. In retinal starburst amacrine cells, transformations from synaptic input to output occur within individual dendrites and mediate direction selectivity, but directional signal fidelity at individual synaptic outputs and correlated activity among neighboring outputs on starburst dendrites have not been examined systematically. Here, we record visually evoked calcium signals simultaneously at many individual synaptic outputs within single starburst amacrine cells in mouse retina. We measure visual receptive fields of individual output synapses and show that small groups of outputs are functionally compartmentalized within starburst dendrites, creating distinct computational units. Inhibition enhances compartmentalization and directional tuning of individual outputs but also decreases the signal-to-noise ratio. Simulations suggest, however, that the noise underlying output signal variability is well tolerated by postsynaptic direction-selective ganglion cells, which integrate convergent inputs to acquire reliable directional information. Published by Elsevier Inc.

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

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    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.

  14. New generation of dendritic cell vaccines.

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    Radford, Kristen J; Caminschi, Irina

    2013-02-01

    Dendritic cells (DC) play a pivotal role in the induction and regulation of immune responses, including the induction of cytotoxic T lymphocytes (CTL) responses. These are essential for the eradication of cancers and pathogens including HIV and malaria, for which there are currently no effective vaccines. New developments in our understanding of DC biology have identified the key DC subset responsible for CTL induction, which is now an attractive candidate to target for vaccination. These DC are characterized by expression of novel markers Clec9A and XCR1, and a specialized capacity to cross-present antigen (Ag) from tumors and pathogens that do not directly infect DC. New generation DC vaccines that specifically target the cross-presenting DC in vivo have already demonstrated potential in preclinical animal models but the challenge remains to translate these findings into clinically efficacous vaccines in man. This has been greatly facilitated by the recent identification of the equivalent Clec9A(+) XCR1(+) cross-presenting DC in human lymphoid tissues and peripheral tissues that are key sites for vaccination administration. These findings combined with further studies on DC subset biology have important implications for the design of new CTL-mediated vaccines.

  15. Hypergravity Effects on Dendritic Cells and Vascular Wall Interactions

    Science.gov (United States)

    Bellik, L.; Parenti, A.; Ledda, F.; Basile, V.; Romano, G.; Fusi, F.; Monici, M.

    2009-01-01

    Dendritic cells (DCs), the most potent antigen-presenting cells inducing specific immune responses, are involved in the pathogenesis of atherosclerosis. In this inflammatory disease, DCs increase in number, being particularly abundant in the shoulder regions of plaques. Since the exposure to altered gravitational conditions results in a significant impairment of the immune function, the aim of this study was to investigate the effects of hypergravity on both the function of DCs and their interactions with the vascular wall cells. Monocytes from peripheral blood mononuclear cells of healthy volunteers were sorted by CD14+ magnetic beads selection, cultured for 6 days in medium supplemented with GM-CSF and IL-4, followed by a further maturation stimulus. DC phenotype, assessed by flow cytometry, showed a high expression of the specific DC markers CD80, CD86, HLA-DR and CD83. The DCs obtained were then exposed to hypergravitational stimuli and their phenotype, cytoskeleton, ability to activate lymphocytes and interaction with vascular wall cells were investigated. The findings showed that the exposure to hypergravity conditions resulted in a significant impairment of DC cytoskeletal organization, without affecting the expression of DC markers. Moreover, an increase in DC adhesion to human vascular smooth muscle cells and in their ability to activate lymphocytes was observed.

  16. Systems immunology allows a new view on human dendritic cells.

    Science.gov (United States)

    Schultze, Joachim L; Aschenbrenner, Anna C

    2018-02-24

    As the most important antigen-presenting cells, dendritic cells connect the innate and adaptive part of our immune system and play a pivotal role in our course of action against invading pathogens as well as during successful vaccination. Immunologists have therefore studied these cells in great detail using flow cytometry-based analyses, in vitro assays and in vivo models, both in murine models and in humans. Albeit, sophisticated, classical immunological, and molecular approaches were often unable to unequivocally determine the subpopulation structure of the dendritic cell lineage and not surprisingly, conflicting results about dendritic cell subsets co-existed throughout the last decades. With the advent of systems approaches and the most recent introduction of -omics approaches on the single cell level combined with multi-colour flow cytometry or mass cytometry, we now enter an era allowing us to define cell population structures with an unprecedented precision. We will report here on the most recent studies applying these technologies to human dendritic cells. Proper delineation of and definition of molecular signatures for the different human dendritic cell subsets will greatly facilitate studying these cells in the future: understanding their function under physiological as well as pathological conditions. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. 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

  18. Immune roles of dendritic cells in stem cell transplantation.

    Science.gov (United States)

    Zhang, Cheng; Liao, Wenwei; Liu, Furong; Zhu, Xiaofeng; He, Xiaoshun; Hu, Anbin

    2017-11-01

    Dendritic cells (DCs) are professional antigen-presenting cells and initial stimulators for immune response. DCs can shape their functions based on their immune states, which are crucial for the balance of immunity and tolerance to preserve homeostasis. In the immune response involved in stem cell transplantation, DCs also play important roles in inducing immune tolerance and antitumor immunity. After the rapid development of stem cell transplantation technology in recent years, the risks of graft rejection, tumor recurrence, and tumorigenicity are still present after stem cell transplantation. It is important to understand the mechanisms of DC-mediated immune tolerance and stimulation during stem cell transplantation. In this review, we will summarize and analyze the regulatory mechanisms of DCs in stem cell transplantation and their application in clinical settings. It may help to promote the innovation in basic theories and therapeutic approaches of stem cell transplantation. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. Immunity and Tolerance Induced by Intestinal Mucosal Dendritic Cells

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    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.

  20. Complete response of metastatic renal cancer with dendritic cell vaccine

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    Dall'Oglio Marcos

    2003-01-01

    Full Text Available INTRODUCTION: We report a case of metastatic renal cell carcinoma that presented involution following therapy with dendritic cells. CASE REPORT: Male, 51-year old patient underwent left radical nephrectomy in September 1999 due to renal cell carcinoma, evolved with recurrence of the neoplasia in January 2002, confirmed by resection of the lesion. A vaccine therapy based on dendritic cells was then performed during 5 months (4 applications. After this period, there was occurrence of new lesions, whose resection revealed areas of necrosis and inflammatory infiltrate. DISCUSSION: The outcome of renal cell carcinoma is influenced by prognostic factors that confer more aggressive tumor characteristics. However, in cases of recurrence, the systemic therapy with dendritic cells-based vaccine can be associated with a better outcome with regression of disease.

  1. A Model of Dendritic Cell Therapy for Melanoma

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    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.

  2. Cranial irradiation alters dendritic spine density and morphology in the hippocampus.

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    Ayanabha Chakraborti

    Full Text Available Therapeutic irradiation of the brain is a common treatment modality for brain tumors, but can lead to impairment of cognitive function. Dendritic spines are sites of excitatory synaptic transmission and changes in spine structure and number are thought to represent a morphological correlate of altered brain functions associated with hippocampal dependent learning and memory. To gain some insight into the temporal and sub region specific cellular changes in the hippocampus following brain irradiation, we investigated the effects of 10 Gy cranial irradiation on dendritic spines in young adult mice. One week or 1 month post irradiation, changes in spine density and morphology in dentate gyrus (DG granule and CA1 pyramidal neurons were quantified using Golgi staining. Our results showed that in the DG, there were significant reductions in spine density at both 1 week (11.9% and 1 month (26.9% after irradiation. In contrast, in the basal dendrites of CA1 pyramidal neurons, irradiation resulted in a significant reduction (18.7% in spine density only at 1 week post irradiation. Analysis of spine morphology showed that irradiation led to significant decreases in the proportion of mushroom spines at both time points in the DG as well as CA1 basal dendrites. The proportions of stubby spines were significantly increased in both the areas at 1 month post irradiation. Irradiation did not alter spine density in the CA1 apical dendrites, but there were significant changes in the proportion of thin and mushroom spines at both time points post irradiation. Although the mechanisms involved are not clear, these findings are the first to show that brain irradiation of young adult animals leads to alterations in dendritic spine density and morphology in the hippocampus in a time dependent and region specific manner.

  3. Human intestinal dendritic cells as controllers of mucosal immunity

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    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.

  4. Subversion of pulmonary dendritic cell function by paramyxovirus infections.

    Science.gov (United States)

    Guerrero-Plata, Antonieta; Kolli, Deepthi; Hong, Chao; Casola, Antonella; Garofalo, Roberto P

    2009-03-01

    Lower respiratory tract infections caused by the paramyxoviruses human metapneumovirus (hMPV) and respiratory syncytial virus (RSV) are characterized by short-lasting virus-specific immunity and often long-term airway morbidity, both of which may be the result of alterations in the Ag-presenting function of the lung which follow these infections. In this study, we investigated whether hMPV and RSV experimental infections alter the phenotype and function of dendritic cell (DC) subsets that are recruited to the lung. Characterization of lung DC trafficking demonstrated a differential recruitment of plasmacytoid DC (pDC), conventional DC (cDC), and IFN-producing killer DC to the lung and draining lymph nodes after hMPV and RSV infection. In vitro infection of lung DC indicated that in pDC, production of IFN-alpha, TNF-alpha, and CCL5 was induced only by hMPV, whereas CCL3 and CCL4 were induced by both viruses. In cDC, a similar repertoire of cytokines was induced by hMPV and RSV, except for IFN-beta, which was not induced by RSV. The function of lung pDC was altered following hMPV or RSV infection in vivo, as we demonstrated a reduced capacity of lung pDC to produce IFN-alpha as well as other cytokines including IL-6, TNF-alpha, CCL2, CCL3, and CCL4 in response to TLR9 stimulation. Moreover, we observed an impaired capacity of cDC from infected mice to present Ag to CD4(+) T cells, an effect that lasted beyond the acute phase of infection. Our findings suggest that acute paramyxovirus infections can alter the long-term immune function of pulmonary DC.

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

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    Sandra J van Vliet

    2009-10-01

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

  6. Human monocytes differentiate into dendritic cells subsets that induce anergic and regulatory T cells in sepsis.

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    Valérie Faivre

    Full Text Available BACKGROUND: Sepsis is a multifactorial pathology with high susceptibility to secondary infections. Innate and adaptive immunity are affected in sepsis, including monocyte deactivation. METHODOLOGY/PRINCIPAL FINDINGS: To better understand the effects of alterations in monocytes on the regulation of immune responses during sepsis, we analyzed their differentiation in dendritic cell (DC. Cells from septic patients differentiated overwhelmingly into CD1a-negative DC, a population that was only a minor subset in controls and that is so far poorly characterized. Analysis of T cell responses induced with purified CD1a-negative and CD1a+ DC indicated that (i CD1a-negative DC from both healthy individuals and septic patients fail to induce T cell proliferation, (ii TGFβ and IL-4 were strongly produced in mixed leukocyte reaction (MLR with control CD1a-negative DC; reduced levels were produced with patients DC together with a slight induction of IFNγ, (iii compared to controls, CD1a+ DC derived from septic patients induced 3-fold more Foxp3+ T cells. CONCLUSION/SIGNIFICANCE: Our results indicate a strong shift in DC populations derived from septic patients' monocytes with expanded cell subsets that induce either T cell anergy or proliferation of T cells with regulatory potential. Lower regulatory cytokines induction on a per cell basis by CD1a-negative dendritic cells from patients points however to a down regulation of immune suppressive abilities in these cells.

  7. Macrophages as APC and the dendritic cell myth.

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    Hume, David A

    2008-11-01

    Dendritic cells have been considered an immune cell type that is specialized for the presentation of Ag to naive T cells. Considerable effort has been applied to separate their lineage, pathways of differentiation, and effectiveness in Ag presentation from those of macrophages. This review summarizes evidence that dendritic cells are a part of the mononuclear phagocyte system and are derived from a common precursor, responsive to the same growth factors (including CSF-1), express the same surface markers (including CD11c), and have no unique adaptation for Ag presentation that is not shared by other macrophages.

  8. CD163 positive subsets of blood dendritic cells

    DEFF Research Database (Denmark)

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

    2006-01-01

    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...... transcriptase polymerase chain reaction. The effect of glucocorticoid and phorbol ester stimulation on monocyte and dendritic cell CD163 and CD91 expression was investigated in cell culture of mononuclear cells using multicolor flow cytometry. We identified two CD163+ subsets in human blood with dendritic cell...... characteristics, CD163lo and CD163hi, together constituting a substantial fraction of DCs. Both subsets were characterized as [lin]- CD4+ ILT3+ HLA-DR+ CD11c+ by flow cytometry, and CD163 mRNA was readily detectable in MACS purified human DCs. CD163 on DCs was upregulated by glucocorticoid, and treatment...

  9. Differential impact of diesel particle composition on pro-allergic dendritic cell function.

    Science.gov (United States)

    Braun, Andrea; Bewersdorff, Mayte; Lintelmann, Jutta; Matuschek, Georg; Jakob, Thilo; Göttlicher, Martin; Schober, Wolfgang; Buters, Jeroen T M; Behrendt, Heidrun; Mempel, Martin

    2010-01-01

    Diesel exhaust particles (DEP) were described as potent adjuvant in the induction and maintenance of allergic diseases, suggesting that they might play a role in the increase of allergic diseases in the industrialized countries. However, the cellular basis by which these particles enhance allergic immune responses is still a matter of debate. Thus, we exposed immature murine bone marrow-derived dendritic cells (BMDC) to different particles or particle-associated organic compounds in the absence or presence of the maturation stimuli lipopolysaccharide (LPS) and analyzed the cellular maturation, viability, and cytokine production. Furthermore, we monitored the functionality of particle-exposed BMDC to suppress B cell isotype switching to immunoglobulin (Ig) E. Only highly polluted DEP (standard reference material 1650a [SRM1650a]) but not particle-associated organic compounds or less polluted DEP from modern diesel engines were able to modulate the dendritic cell phenotype. SRM1650a particles significantly suppressed LPS-induced IL-12p70 production in murine BMDC, whereas cell-surface marker expression was not altered. Furthermore, SRM1650a-exposed immature BMDC lost the ability to suppress IgE isotype switch in B cells. This study revealed that highly polluted DEP not only interfere with dendritic cell maturation but also additionally with dendritic cell function, thus suggesting a role in T(h)2 immune deviation.

  10. 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

  11. Building on Dendritic Cell Subsets to Improve Cancer Vaccines

    OpenAIRE

    Palucka, Karolina; Ueno, Hideki; Zurawski, Gerard; Fay, Joseph; Banchereau, Jacques

    2010-01-01

    T cells can reject established tumors when adoptively transferred into patients, thereby demonstrating that the immune system can be harnessed for cancer therapy. However, such passive immunotherapy is unlikely to maintain memory T cells that might control tumor outgrowth on the long term. Active immunotherapy with vaccines has the potential to induce tumor-specific effector and memory T cells. Vaccines act through dendritic cells (DCs) which induce, regulate and maintain T cell immunity. Cli...

  12. 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

  13. Dendritic cell vaccines in melanoma: from promise to proof?

    NARCIS (Netherlands)

    Lesterhuis, W. J.; Aarntzen, E. H. J. G.; de Vries, I. J. M.; Schuurhuis, D. H.; Figdor, C. G.; Adema, G. J.; Punt, C. J. A.

    2008-01-01

    Dendritic cells (DC) are the directors of the immune system, capable of inducing tumour antigen-specific T- and B-cell responses. As such, they are currently applied in clinical studies in cancer patients. Early small clinical trials showed promising results, with frequent induction of anti-cancer

  14. Investigating Human Dendritic Cell Immune Responses to Borrelia burgdorferi

    NARCIS (Netherlands)

    Mason, Lauren M. K.; Hovius, Joppe W. R.

    2018-01-01

    Dendritic cells (DCs) are professional antigen-presenting cells that recognize and phagocytose pathogens, and help to orchestrate adaptive immune responses to combat them. DCs are abundant in the skin where Borrelia burgdorferi first enters the body during a tick bite, and are thus critical in

  15. Natural killer cells complot with dendritic cells 

    Directory of Open Access Journals (Sweden)

    Aleksandra Bielawska-Pohl

    2013-03-01

    Full Text Available Dendritic cells (DC were initially considered as antigen presenting cells participating in the polarization of the immune response. Further understanding of their biology allowed determining their additional functions such as immunoregulatory and cytotoxicity. Until recently natural killer (NK cells were known as a homogeneous population of lymphocytes capable of non-specific recognizing and eliminating target cells. Now it is widely accepted that NK cells, as a heterogeneous population, may also possess immunomodulatory functions. Moreover, the most recent analysis of the interactions between DC and NK cells revealed the exceptional functions of these cells. As a result of these studies the existence of bitypic cell population was postulated. The distinguishing features of these hybrid cells are: the expression of surface receptors typical for NK cells and DC, the cytotoxic activity, the production of interferons as well as their ability to present antigen after prior stimulation. Despite the lack of strong direct evidence that the same cell can be both cytotoxic and effectively present the antigen at the same time, there are experimental findings suggesting that generated ex vivo bitypic cells may be used in antitumor therapy. 

  16. Influence of Dendritic Cells on B-Cell Responses during HIV Infection

    Directory of Open Access Journals (Sweden)

    Johanne Poudrier

    2012-01-01

    Full Text Available Dendritic cells (DCs modulate B-cell differentiation, activation, and survival mainly through production of growth factors such as B lymphocyte stimulator (BLyS/BAFF. DC populations have been reported to be affected in number, phenotype and function during HIV infection and such alterations may contribute to the dysregulation of the B-cell compartment. Herein, we reflect on the potential impact of DC on the pathogenesis of HIV-related B cell disorders, and how DC status may modulate the outcome of mucosal B cell responses against HIV, which are pivotal to the control of disease. A concept that could be extrapolated to the overall outcome of HIV disease, whereby control versus progression may reside in the host’s capacity to maintain DC homeostasis at mucosal sites, where DC populations present an inherent capacity of modulating the balance between tolerance and protection, and are amongst the earliest cell types to be exposed to the virus.

  17. 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.

  18. 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...

  19. Langerhans Cells - The Macrophage in Dendritic Cell Clothing.

    Science.gov (United States)

    Doebel, Thomas; Voisin, Benjamin; Nagao, Keisuke

    2017-11-01

    Our assumptions on the identity and functions of Langerhans cells (LCs) of the epidermis have undergone considerable changes. Once thought to be prototypic representatives of the dendritic cell (DC) lineage, they are now considered to be a specialized subset of tissue-resident macrophages. Despite this, LCs display a remarkable mixture of properties. Like many tissue macrophages, they self-maintain locally. However, unlike tissue macrophages and similar to DCs, they homeostatically migrate to lymph nodes and present antigen to antigen-specific T cells. Current evidence indicates that the immune responses initiated by LCs are complex and dependent on antigenic properties and localization of the stimulus. This complexity is reflected in the recently demonstrated roles of LCs in type 17, regulatory, and humoral immune responses. Copyright © 2017. Published by Elsevier Ltd.

  20. 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

  1. 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

  2. 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

  3. EVIDENCE OF CELL-NONAUTONOMOUS CHANGES IN DENDRITE AND DENDRITIC SPINE MORPHOLOGY IN THE MET-SIGNALING DEFICIENT MOUSE FOREBRAIN

    Science.gov (United States)

    Judson, Matthew C.; Eagleson, Kathie L.; Wang, Lily; Levitt, Pat

    2010-01-01

    Human genetic findings and murine neuroanatomical expression mapping have intersected to implicate Met receptor tyrosine kinase signaling in the development of forebrain circuits controlling social and emotional behaviors that are atypical in autism spectrum disorders (ASD). To clarify roles for Met signaling during forebrain circuit development in vivo, we generated mutant mice (Emx1Cre/Metfx/fx) with an Emx1-Cre-driven deletion of signaling-competent Met in dorsal pallially-derived forebrain neurons. Morphometric analyses of Lucifer Yellow-injected pyramidal neurons in postnatal day 40 anterior cingulate cortex (ACC) revealed no statistically significant changes in total dendritic length, but a selective reduction in apical arbor length distal to the soma in Emx1Cre/Metfx/fx neurons relative to wild type, consistent with a decrease in the total tissue volume sampled by individual arbors in the cortex. The effects on dendritic structure appear to be circuit-selective, as basal arbor length was increased in Emx1Cre/Metfx/fx layer 2/3 neurons. Spine number was not altered on Emx1Cre/Metfx/fx pyramidal cell populations studied, but spine head volume was significantly increased (~20%). Cell-nonautonomous, circuit-level influences of Met signaling on dendritic development were confirmed by studies of medium spiny neurons (MSN), which do not express Met, but receive Met-expressing corticostriatal afferents during development. Emx1Cre/Metfx/fx MSN exhibited robust increases in total arbor length (~20%). Like in the neocortex, average spine head volume was also increased (~12%). These data demonstrate that a developmental loss of presynaptic Met receptor signaling can affect postsynaptic morphogenesis and suggest a mechanism whereby attenuated Met signaling could disrupt both local and long-range connectivity within circuits relevant to ASD. PMID:20853516

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

    OpenAIRE

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

    2009-01-01

    International audience; BACKGROUND: 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. DESIGN AND METHODS: Microparticles generated from endothelial cell lines, platelets or activated T ...

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

    Lifescience Database Archive (English)

    Full Text Available InP.Bld.05.AllAg.Dendritic_Cells mm9 Input control Blood Dendritic Cells SRX885956,...76,SRX122481,SRX667880,SRX667874,SRX667878 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.Bld.05.AllAg.Dendritic_Cells.bed ...

  6. File list: Unc.Bld.50.AllAg.Dendritic_Cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.Bld.50.AllAg.Dendritic_Cells hg19 Unclassified Blood Dendritic Cells SRX818200,...203,SRX818202,SRX818182,SRX818195,SRX818196,SRX818181 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Unc.Bld.50.AllAg.Dendritic_Cells.bed ...

  7. File list: InP.Bld.10.AllAg.Dendritic_Cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.Bld.10.AllAg.Dendritic_Cells hg19 Input control Blood Dendritic Cells SRX627429...,SRX627427 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/InP.Bld.10.AllAg.Dendritic_Cells.bed ...

  8. 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 ...

  9. 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 cells * cancer vaccines Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.519, year: 2001

  10. Processing of MHC class II in dendritic cells

    NARCIS (Netherlands)

    ten Broeke, A.G.

    2012-01-01

    In the past years we performed studies to gain more insight into the processing of major histocompatibility class II (MHC class II) in dendritic cells. We focused on the sorting mechanisms of MHC class II, the degradation of its associated Ii and peptide loading at the endosomal system. In addition,

  11. 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 ...

  12. Virosome-mediated delivery of protein antigens to dendritic cells

    NARCIS (Netherlands)

    Bungener, L; Serre, K; Bijl, L; Leserman, L; Wilschut, J; Daemen, T; Machy, P

    2002-01-01

    Virosomes are reconstituted viral membranes in which protein can be encapsulated. Fusion-active virosomes, fusion-inactive virosomes and liposomes were used to study the conditions needed for delivery of encapsulated protein antigen ovalbumin (OVA) to dendritic cells (DCs) for MHC class I and 11

  13. 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 ...

  14. Blastic Plasmacytoid Dendritic Cell Leukemia in a Black Malian

    African Journals Online (AJOL)

    2017-06-28

    Jun 28, 2017 ... (BPDCN) is an acute myeloblastic leukemia (AML) characterized by the clonal proliferation of precursors of plasmacytoid dendritic cells. It is categorized as an acute myeloid neoplasm by the 2008 world health organization classification of neoplasms. Over 90% of cases present with skin lesions in the form ...

  15. 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 cells * tumour vaccines Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.330, year: 2001

  16. Modulation of synaptic potentials and cell excitability by dendritic

    Indian Academy of Sciences (India)

    Its major cellular substrates, the medium spiny (MS) neurons, possess a wide variety of dendritic active conductances that may modulate the excitatory post synaptic potentials (EPSPs) and cell excitability. We examine this issue using a biophysically detailed 189-compartment stylized model of the NAc MS neuron, ...

  17. Innate signaling and regulation of Dendritic cell immunity

    NARCIS (Netherlands)

    van Vliet, Sandra J.; den Dunnen, Jeroen; Gringhuis, Sonja I.; Geijtenbeek, Teunis Bh; van Kooyk, Yvette

    2007-01-01

    Dendritic cells are crucial in pathogen recognition and induction of specific immune responses to eliminate pathogens from the infected host. Host recognition of invading microorganisms relies on evolutionarily conserved, germline-encoded pattern-recognition receptors (PRRs) that are expressed by

  18. Dendritic cell subsets digested: RNA sensing makes the difference!

    NARCIS (Netherlands)

    Buschow, S.I.; Figdor, C.G.

    2010-01-01

    In this issue of Immunity, Luber et al. (2010) report a comprehensive quantitative proteome of in vivo mouse spleen dendritic cell (DC) subsets: a data set of encyclopedic value already revealing that DC subsets exploit different RNA sensors for virus recognition.

  19. Modulation of synaptic potentials and cell excitability by dendritic ...

    Indian Academy of Sciences (India)

    Modulation of synaptic potentials and cell excitability by dendritic. KIR and KAs channels in nucleus accumbens medium spiny neurons: A computational study. JESSY JOHN* and ROHIT MANCHANDA. Biomedical Engineering group, Department of Biosciences and Bioengineering, Indian Institute of Technology. Bombay ...

  20. Menage a trois: Borrelia, dendritic cells, and tick saliva interactions

    NARCIS (Netherlands)

    Mason, Lauren M. K.; Veerman, Christiaan C.; Geijtenbeek, Teunis B. H.; Hovius, Joppe W. R.

    2014-01-01

    Borrelia burgdorferi sensu lato, the causative agent of Lyme borreliosis, is inoculated into the skin during an lxodes tick bite where it is recognised and captured by dendritic cells (DCs). However, considering the propensity of Borrelia to disseminate, it would appear that DCs fall short in

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

    OpenAIRE

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

    2016-01-01

    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 intermediat...

  2. 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.

  3. 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...

  4. 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.

  5. Immunohistochemical analysis of small plaque parapsoriasis: involvement of dendritic cells.

    Science.gov (United States)

    Zeybek, N Dilara; Asan, Esin; Erbil, A Hakan; Dagdeviren, Attila

    2008-01-01

    Small plaque parapsoriasis (SPP) is one of the cutaneous T-cell lymphoproliferative disorders. The aim of the present study was to show the antigenic profile of a subset of dendritic cells and lymphocytes in SPP in comparison with normal cells to provide data on the role of these two cell types in the pathogenesis of SPP. Skin biopsy specimens of lesions were obtained from 8 patients with SPP. Biopsies of the healthy skin from 9 control individuals were also analyzed. Immunohistochemistry was performed on the frozen tissue sections to reveal binding of anti-HLA Class II, anti-CD1a, anti-CD4, anti-CD8, anti-CD44, anti-CD45, and anti-CD68 monoclonal antibodies. There was a statistically significant increase in the number of CD1a(+), Langerhans cells (LCs), HLA-DR-immunoreactive and, CD1a-positive dermal dendritic cells and CD68(+) macrophages in the SPP group (p=0.008, 0.008, 0.002 and <0.0009, respectively). The number of lymphocytes positive for CD4, CD8 and CD45 was significantly higher than normal in the SPP group (p=0.015, <0.0009 and <0.0009, respectively). Our study demonstrates that both peptide- and lipid-based antigens are involved in the persistent antigenic exposure in SPP. Dendritic cells play a pivotal role in SPP by presenting antigens by both LC and dermal dendritic cells via MHC Class II and CD1a molecules. The CD68(+) macrophages are thought to be involved in the immune response in this pathology as an antigen-presenting cell.

  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. Murine and Human Model Systems for the Study of Dendritic Cell Immunobiology.

    Science.gov (United States)

    Hargadon, Kristian M

    2016-01-01

    Dendritic cells are a population of innate immune cells that possess their own effector functions as well as numerous regulatory properties that shape the activity of other innate and adaptive cells of the immune system. Following their development from either lymphoid or myeloid progenitors, the function of dendritic cells is tightly linked to their maturation and activation status. Differentiation into specialized subsets of dendritic cells also contributes to the diverse immunologic functions of these cells. Because of the key role played by dendritic cells in the regulation of both immune tolerance and activation, significant efforts have been focused on understanding dendritic cell biology. This review highlights the model systems currently available to study dendritic cell immunobiology and emphasizes the advantages and disadvantages to each system in both murine and human settings. In particular, in vitro cell culture systems involving immortalized dendritic cell lines, ex vivo systems for differentiating and expanding dendritic cells from their precursor populations, and systems for expanding, ablating, and manipulating dendritic cells in vivo are discussed. Emphasis is placed on the contribution of these systems to our current understanding of the development, function, and immunotherapeutic applications of dendritic cells, and insights into how these models might be extended in the future to answer remaining questions in the field are discussed.

  8. THE CHEMOIMMUNOTHERAPY BASED ON DENDRITIC CELLS AND CISPLATIN IN EXPERIMENT

    Directory of Open Access Journals (Sweden)

    Gorbach O. I.

    2014-08-01

    Full Text Available The aim of the study was to develop a scheme of combined chemoimmunotherapy and to investigate antitumor and immunomodulatory activity of chemoimmunotherapy regimen using the vaccine based on dendritic cells and low-doses of cisplatin in CBA mice with sarcoma-37. Maximal antitumor and immunomodulatory effects were observed after application of the vaccine based on dendritic cells in combination with doses of cisplatin concentration of 2 mg/kg. Among significant immunomodulatory effects of combination therapy it has to be noted the increased functional activity of natural immunity,in particular, enhancing of cytotoxic activity of natural killer cells and the ability of peritoneal macrophages, neutrophils and spleen macrophages to increase their absorbing activity and to produce the active oxygen forms. The obtained results prove the expediency of combining of chemo- and immunotherapeutic methods for the development of more effective approaches to prevent recurrence and metastasis after primary treatment of cancer patients.

  9. Viral piracy: HIV-1 targets dendritic cells for transmission.

    Science.gov (United States)

    Lekkerkerker, Annemarie N; van Kooyk, Yvette; Geijtenbeek, Teunis B H

    2006-04-01

    Dendritic cells (DCs), the professional antigen presenting cells, are critical for host immunity by inducing specific immune responses against a broad variety of pathogens. Remarkably the human immunodeficiency virus-1 (HIV-1) subverts DC function leading to spread of the virus. At an early phase of HIV-1 transmission, DCs capture HIV-1 at mucosal surfaces and transmit the virus to T cells in secondary lymphoid tissues. Capture of the virus on DCs takes place via C-type lectins of which the dendritic cell-specific intercellular adhesion molecule-3 (ICAM-3) grabbing nonintegrin (DC-SIGN) is the best studied. DC-SIGN-captured HIV-1 particles accumulate in CD81(+) multivesicular bodies (MVBs) in DCs and are subsequently transmitted to CD4+ T cells resulting in infection of T cells. The viral cell-to-cell transmission takes place at the DC-T cell interface termed the infectious synapse. Recent studies demonstrate that direct infection of DCs contributes to the transmission to T cells at a later phase. Moreover, the infected DCs may function as cellular reservoirs for HIV-1. This review discusses the different processes that govern viral piracy of DCs by HIV-1, emphasizing the intracellular routing of the virus from capture on the cell surface to egress in the infectious synapse.

  10. Utilization of oncoprotein-pulsed dendritic cells as tumor vaccines

    Czech Academy of Sciences Publication Activity Database

    Bubeník, Jan

    2001-01-01

    Roč. 127, č. 8 (2001), s. 463-466 ISSN 0171-5216 R&D Projects: GA MZd NC5526; GA MZd NC45011; GA ČR GA312/98/0826; GA ČR GA312/99/0542; GA ČR GA301/00/0114 Institutional research plan: CEZ:AV0Z5052915 Keywords : dendritic cells * tumor vaccines * oncoproteins Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.194, year: 2001

  11. 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.

  12. 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.

  13. 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.

  14. 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...

  15. 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.

  16. Re-Emergence of Dendritic Cell Vaccines for Cancer Treatment.

    Science.gov (United States)

    Saxena, Mansi; Bhardwaj, Nina

    2018-02-01

    Dendritic cells (DCs) are essential in immunity owing to their role in activating T cells, thereby promoting antitumor responses. Tumor cells, however, hijack the immune system, causing T cell exhaustion and DC dysfunction. Tumor-induced T cell exhaustion may be reversed through immune checkpoint blockade (ICB); however, this treatment fails to show clinical benefit in many patients. While ICB serves to reverse T cell exhaustion, DCs are still necessary to prime, activate, and direct the T cells to target tumor cells. In this review we provide a brief overview of DC function, describe mechanisms by which DC functions are disrupted by the tumor microenvironment, and highlight recent developments in DC cancer vaccines. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. Overexpression of cypin alters dendrite morphology, single neuron activity, and network properties via distinct mechanisms

    Science.gov (United States)

    Rodríguez, Ana R.; O'Neill, Kate M.; Swiatkowski, Przemyslaw; Patel, Mihir V.; Firestein, Bonnie L.

    2018-02-01

    Objective. This study investigates the effect that overexpression of cytosolic PSD-95 interactor (cypin), a regulator of synaptic PSD-95 protein localization and a core regulator of dendrite branching, exerts on the electrical activity of rat hippocampal neurons and networks. Approach. We cultured rat hippocampal neurons and used lipid-mediated transfection and lentiviral gene transfer to achieve high levels of cypin or cypin mutant (cypinΔPDZ PSD-95 non-binding) expression cellularly and network-wide, respectively. Main results. Our analysis revealed that although overexpression of cypin and cypinΔPDZ increase dendrite numbers and decrease spine density, cypin and cypinΔPDZ distinctly regulate neuronal activity. At the single cell level, cypin promotes decreases in bursting activity while cypinΔPDZ reduces sEPSC frequency and further decreases bursting compared to cypin. At the network level, by using the Fano factor as a measure of spike count variability, cypin overexpression results in an increase in variability of spike count, and this effect is abolished when cypin cannot bind PSD-95. This variability is also dependent on baseline activity levels and on mean spike rate over time. Finally, our spike sorting data show that overexpression of cypin results in a more complex distribution of spike waveforms and that binding to PSD-95 is essential for this complexity. Significance. Our data suggest that dendrite morphology does not play a major role in cypin action on electrical activity.

  18. Divergent Effects of Dendritic Cells on Pancreatitis

    Science.gov (United States)

    2015-09-01

    Sagi,3 and George Miller1,2 1Department of Surgery , 2Department of Cell Biology, 3Department of Biochemistry and Molecular Pharmacology, and...establish orthotopic pancreatic lesions, we grafted PDECs harboring oncogenic KRasG12D by direct intrapancreatic injection via laparotomy as we have...or Raji lymphoma cells. For our human experiments, proteins were also isolated from human pancreatic duct fluid harvested at surgery from patients

  19. Dendritic maturation in cat retinal ganglion cells: a Lucifer yellow study.

    Science.gov (United States)

    Dann, J F; Buhl, E H; Peichl, L

    1987-09-11

    The dendritic morphology of developing cat alpha- and beta-retinal ganglion cells was investigated by intracellular injection of Lucifer yellow. In both cell classes the basic pattern of adult morphology was present at birth. However, the presence of transient small spiny protrusions along the dendrites was characteristic of early postnatal cells. Many alpha-cells were further distinguished by a small degree of dendritic bi-stratification which disappeared within the first 5 postnatal days. Therefore during the period before the eyes opened (P7-P10) there was a considerable degree of modification and maturation in dendritic morphology in both classes of retinal ganglion cells. alpha- and beta-cells exhibited differing temporal patterns of dendritic growth, which argues against a 'passive-stretching' hypothesis that explains dendritic field enlargement solely as an effect of retinal areal growth.

  20. Classing it up to get noticed : MHC class 1 antigen display in dendritic cells and neuroblastoma

    NARCIS (Netherlands)

    Spel, Lotte

    2018-01-01

    In this thesis I have explored the process of MHC-1-mediated antigen presentation in two distinctive cell types: dendritic cells and neuroblastoma tumor cells. Dendritic cells (DCs) are pivotal players that bridge innate and adaptive immunity. DCs are able to engulf tumor-derived material and

  1. 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.

  2. Dendritic Cell Cancer Vaccines: From the Bench to the Bedside

    Directory of Open Access Journals (Sweden)

    Tamar Katz

    2014-10-01

    Full Text Available The recognition that the development of cancer is associated with acquired immunodeficiency, mostly against cancer cells themselves, and understanding pathways inducing this immunosuppression, has led to a tremendous development of new immunological approaches, both vaccines and drugs, which overcome this inhibition. Both “passive” (e.g. strategies relying on the administration of specific T cells and “active” vaccines (e.g. peptide-directed or whole-cell vaccines have become attractive immunological approaches, inducing cell death by targeting tumor-associated antigens. Whereas peptide-targeted vaccines are usually directed against a single antigen, whole-cell vaccines (e.g. dendritic cell vaccines are aimed to induce robust responsiveness by targeting several tumor-related antigens simultaneously. The combination of vaccines with new immuno-stimulating agents which target “immunosuppressive checkpoints” (anti-CTLA-4, PD-1, etc. is likely to improve and maintain immune response induced by vaccination.

  3. 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.

  4. 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...

  5. 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.

  6. 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.

  7. Alterations in p53-specific T cells and other lymphocyte subsets in breast cancer patients during vaccination with p53-peptide loaded dendritic cells and low-dose interleukin-2

    DEFF Research Database (Denmark)

    Svane, Inge Marie; Pedersen, Anders E; Nikolajsen, Kirsten

    2008-01-01

    We have previously established a cancer vaccine using autologous DCs, generated by in vitro stimulation with IL-4 and GM-CSF, and pulsed with six HLA-A*0201 binding wild-type p53 derived peptides. This vaccine was used in combination with low-dose interleukin-2 in a recently published clinical...... Phase II trial where 26 HLA-A2+ patients with progressive late-stage metastatic breast cancer (BC) were included. Almost 1/3rd of the patients obtained stable disease or minor regression during treatment with a positive correlation to tumour over-expression of p53. In the present study, we performed...... a comprehensive analysis of the effector stage of the p53-specific CD8+ T cells by the use of Dextramer Technology and multicolour FACS. Pre- and post-treatment blood samples from eight BC patients were analysed. Independent of clinical outcome p53-specific T cells were phenotypic distinctly antigen experienced...

  8. 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

  9. Investigating Evolutionary Conservation of Dendritic Cell Subset Identity and Functions.

    Science.gov (United States)

    Vu Manh, Thien-Phong; Bertho, Nicolas; Hosmalin, Anne; Schwartz-Cornil, Isabelle; Dalod, Marc

    2015-01-01

    Dendritic cells (DCs) 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, organs, and

  10. 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.

  11. Blastic plasmacytoid dendritic cell neoplasm: challenges and future prospects

    Directory of Open Access Journals (Sweden)

    Trottier AM

    2017-12-01

    Full Text Available Amy M Trottier, Sonia Cerquozzi, Carolyn J Owen Division of Hematology and Hematological Malignancies, University of Calgary, Foothills Medical Centre, Calgary, AB, Canada Abstract: Blastic plasmacytoid dendritic cell neoplasm (BPDCN is a rare CD4+ CD56+ myeloid malignancy that is challenging to diagnose and treat. BPDCN typically presents with nonspecific cutaneous lesions with or without extra-cutaneous manifestations before progressing to leukemia. Currently, there is no standard of care for the treatment of BPDCN and various approaches have been used including acute myeloid leukemia, acute lymphoblastic leukemia, and lymphoma-based regimens with or without stem cell transplantation. Despite these treatment approaches, the prognosis of BPDCN remains poor and there is a lack of prospective data upon which to base treatment decisions. Recent work examining the mutational landscape and gene expression profiles of BPDCN has identified a number of potential therapeutic targets. One such target is CD123, the α subunit of the human interleukin-3 receptor, which is the subject of intervention studies using the novel agent SL-401. Other investigational therapies include UCART123, T-cell immunotherapy, and venetoclax. Prospective trials are needed to determine the best treatment for this uncommon and aggressive neoplasm. Keywords: BPDCN, myeloid, neoplasm, cutaneous, dendritic cell

  12. Regulating Immunogenicity and Tolerogenicity of Bone Marrow-Derived Dendritic Cells through Modulation of Cell Surface Glycosylation by Dexamethasone Treatment

    Directory of Open Access Journals (Sweden)

    Kevin Lynch

    2017-10-01

    Full Text Available Dendritic cellular therapies and dendritic cell vaccines show promise for the treatment of autoimmune diseases, the prolongation of graft survival in transplantation, and in educating the immune system to fight cancers. Cell surface glycosylation plays a crucial role in the cell–cell interaction, uptake of antigens, migration, and homing of DCs. Glycosylation is known to change with environment and the functional state of DCs. Tolerogenic DCs (tDCs are commonly generated using corticosteroids including dexamethasone, however, to date, little is known on how corticosteroid treatment alters glycosylation and what functional consequences this may have. Here, we present a comprehensive profile of rat bone marrow-derived dendritic cells, examining their cell surface glycosylation profile before and after Dexa treatment as resolved by both lectin microarrays and lectin-coupled flow cytometry. We further examine the functional consequences of altering cell surface glycosylation on immunogenicity and tolerogenicity of DCs. Dexa treatment of rat DCs leads to profoundly reduced expression of markers of immunogenicity (MHC I/II, CD80, CD86 and pro-inflammatory molecules (IL-6, IL-12p40, inducible nitric oxide synthase indicating a tolerogenic phenotype. Moreover, by comprehensive lectin microarray profiling and flow cytometry analysis, we show that sialic acid (Sia is significantly upregulated on tDCs after Dexa treatment, and that this may play a vital role in the therapeutic attributes of these cells. Interestingly, removal of Sia by neuraminidase treatment increases the immunogenicity of immature DCs and also leads to increased expression of pro-inflammatory cytokines while tDCs are moderately protected from this increase in immunogenicity. These findings may have important implications in strategies aimed at increasing tolerogenicity where it is advantageous to reduce immune activation over prolonged periods. These findings are also relevant in

  13. 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 cells * tumour vaccines Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.513, year: 2000

  14. 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...

  15. 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

  16. Boosting antibody responses by targeting antigens to dendritic cells.

    Science.gov (United States)

    Caminschi, Irina; Shortman, Ken

    2012-02-01

    Delivering antigens directly to dendritic cells (DCs) in situ, by injecting antigens coupled to antibodies specific for DC surface molecules, is a promising strategy for enhancing vaccine efficacy. Enhanced cytotoxic T cell responses are obtained if an adjuvant is co-administered to activate the DC. Such DC targeting is also effective at enhancing humoral immunity, via the generation of T follicular helper cells. Depending on the DC surface molecule targeted, antibody production can be enhanced even in the absence of adjuvants. In the case of Clec9A as the DC surface target, enhanced antibody production is a consequence of the DC-restricted expression of the target molecule. Few other cells absorb the antigen-antibody construct, therefore, it persists in the bloodstream, allowing sustained antigen presentation, even by non-activated DCs. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Apoptosis and systemic autoimmunity: the dendritic cell connection

    Directory of Open Access Journals (Sweden)

    AA Manfredi

    2009-12-01

    Full Text Available Much effort has been devoted in recent years to the events linking recognition and disposal of apoptotic cells to sustained immunity towards the antigens they contain. Programmed death via apoptosis indeed provides most of the raw material the immune system exploits to establish self tolerance, i.e. to learn how to distinguish between self constituents and foreign antigens, belonging to invading pathogens. In parallel, events occurring during cell death may enable a restricted array of molecules endowed with diverse structure, function and intracellular distribution to satisfy the requirement to evoke and maintain autoimmune responses. Dendritic cells (DCs, the most potent antigen presenting cells, appear to play a crucial role. Here we will discuss some of the constrains regulating the access of dying cells’ antigens to DCs, as well as censorship mechanisms that prevent their maturation and the full explication of their antigen presenting function.

  18. 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.

  19. Krebs cycle rewired for macrophage and dendritic cell effector functions.

    Science.gov (United States)

    Ryan, Dylan Gerard; O'Neill, Luke A J

    2017-10-01

    The Krebs cycle is an amphibolic pathway operating in the mitochondrial matrix of all eukaryotic organisms. In response to proinflammatory stimuli, macrophages and dendritic cells undergo profound metabolic remodelling to support the biosynthetic and bioenergetic requirements of the cell. Recently, it has been discovered that this metabolic shift also involves the rewiring of the Krebs cycle to regulate cellular metabolic flux and the accumulation of Krebs cycle intermediates, notably, citrate, succinate and fumarate. Interestingly, a new role for Krebs cycle intermediates as signalling molecules and immunomodulators that dictate the inflammatory response has begun to emerge. This review will discuss the latest developments in Krebs cycle rewiring and immune cell effector functions, with a particular focus on the regulation of cytokine production. © 2017 Federation of European Biochemical Societies.

  20. Phenotypical heterogeneity of testicular macrophages/dendritic cells in normal adult mice: an immunohistochemical study

    NARCIS (Netherlands)

    Itoh, M.; de rooij, D. G.; Jansen, A.; Drexhage, H. A.

    1995-01-01

    The distribution of macrophage/dendritic cell antigens was investigated immunohistochemically in frozen testis sections of normal A/J mice using a panel of rat monoclonal antibodies against murine macrophage/dendritic cell antigens (F4/80, BM8, MP23, MOMA1, MOMA2, M5/114, BMDM1 and NLDC145).

  1. Development of Type 1 Diabetes: Monocytes and dendritic cells in the pancreas

    NARCIS (Netherlands)

    J.M.C. Welzen-Coppens (Jojanneke)

    2013-01-01

    textabstractThis thesis focuses on the presence of precursors for dendritic cells and the characterization of dendritic cell subsets in the normal pancreas in mice and humans as well as in the pancreas of the NOD mouse, a type 1 diabetes mouse model. Therefore, we give a short introduction to

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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....

  7. Dengue tropism for macrophages and dendritic cells : the host cell effect

    NARCIS (Netherlands)

    Flipse, Jacky; Torres Pedraza, Silvia; Diosa-Toro, Mayra; van der Ende-Metselaar, Heidi; Herrera-Rodriguez, Jose; Urcuqui-Inchima, Silvio; Huckriede, Anke; Rodenhuis-Zybert, Izabela A; Smit, Jolanda M

    Dengue virus infects immune cells, including monocytes, macrophages and dendritic cells (DC). We compared virus infectivity in macrophages and DC, and found that the virus origin determined the cell tropism of progeny virus. The highest efficiency of re-infection was seen for macrophage-derived

  8. 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...

  9. Modulation of Dendritic Cell Activation and Subsequent Th1 Cell Polarization by Lidocaine

    Science.gov (United States)

    Chung, Yeonseok

    2015-01-01

    Dendritic cells play an essential role in bridging innate and adaptive immunity by recognizing cellular stress including pathogen- and damage-associated molecular patterns and by shaping the types of antigen-specific T cell immunity. Although lidocaine is widely used in clinical settings that trigger cellular stress, it remains unclear whether such treatment impacts the activation of innate immune cells and subsequent differentiation of T cells. Here we showed that lidocaine inhibited the production of IL–6, TNFα and IL–12 from dendritic cells in response to toll-like receptor ligands including lipopolysaccharide, poly(I:C) and R837 in a dose-dependent manner. Notably, the differentiation of Th1 cells was significantly suppressed by the addition of lidocaine while the same treatment had little effect on the differentiation of Th17, Th2 and regulatory T cells in vitro. Moreover, lidocaine suppressed the ovalbumin-specific Th1 cell responses in vivo induced by the adoptive transfer of ovalbumin-pulsed dendritic cells. These results demonstrate that lidocaine inhibits the activation of dendritic cells in response to toll-like receptor signals and subsequently suppresses the differentiation of Th1 cell responses. PMID:26445366

  10. 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

  11. Mechanisms of Dendritic Cell Lysosomal Killing of Cryptococcus

    Science.gov (United States)

    Hole, Camaron R.; Bui, Hoang; Wormley, Floyd L.; Wozniak, Karen L.

    2012-10-01

    Cryptococcus neoformans is an opportunistic pulmonary fungal pathogen that disseminates to the CNS causing fatal meningitis in immunocompromised patients. Dendritic cells (DCs) phagocytose C. neoformans following inhalation. Following uptake, cryptococci translocate to the DC lysosomal compartment and are killed by oxidative and non-oxidative mechanisms. DC lysosomal extracts kill cryptococci in vitro; however, the means of antifungal activity remain unknown. Our studies determined non-oxidative antifungal activity by DC lysosomal extract. We examined DC lysosomal killing of cryptococcal strains, anti-fungal activity of purified lysosomal enzymes, and mechanisms of killing against C. neoformans. Results confirmed DC lysosome fungicidal activity against all cryptococcal serotypes. Purified lysosomal enzymes, specifically cathepsin B, inhibited cryptococcal growth. Interestingly, cathepsin B combined with its enzymatic inhibitors led to enhanced cryptococcal killing. Electron microscopy revealed structural changes and ruptured cryptococcal cell walls following treatment. Finally, additional studies demonstrated that osmotic lysis was responsible for cryptococcal death.

  12. 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

  13. Alterations to dendritic spine morphology, but not dendrite patterning, of cortical projection neurons in Tc1 and Ts1Rhr mouse models of Down syndrome.

    Directory of Open Access Journals (Sweden)

    Matilda A Haas

    Full Text Available Down Syndrome (DS is a highly prevalent developmental disorder, affecting 1/700 births. Intellectual disability, which affects learning and memory, is present in all cases and is reflected by below average IQ. We sought to determine whether defective morphology and connectivity in neurons of the cerebral cortex may underlie the cognitive deficits that have been described in two mouse models of DS, the Tc1 and Ts1Rhr mouse lines. We utilised in utero electroporation to label a cohort of future upper layer projection neurons in the cerebral cortex of developing mouse embryos with GFP, and then examined neuronal positioning and morphology in early adulthood, which revealed no alterations in cortical layer position or morphology in either Tc1 or Ts1Rhr mouse cortex. The number of dendrites, as well as dendrite length and branching was normal in both DS models, compared with wildtype controls. The sites of projection neuron synaptic inputs, dendritic spines, were analysed in Tc1 and Ts1Rhr cortex at three weeks and three months after birth, and significant changes in spine morphology were observed in both mouse lines. Ts1Rhr mice had significantly fewer thin spines at three weeks of age. At three months of age Tc1 mice had significantly fewer mushroom spines--the morphology associated with established synaptic inputs and learning and memory. The decrease in mushroom spines was accompanied by a significant increase in the number of stubby spines. This data suggests that dendritic spine abnormalities may be a more important contributor to cognitive deficits in DS models, rather than overall neuronal architecture defects.

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

    Directory of Open Access Journals (Sweden)

    Veronica Rainone

    Full Text Available Dendritic cells play a key role as initiators of T-cell responses, and even if tumour antigen-loaded dendritic cells can induce anti-tumour responses, their efficacy has been questioned, suggesting a need to enhance immunization strategies.We focused on the characterization of bone marrow-derived dendritic cells pulsed with whole tumour lysate (TAA-DC, as a source of known and unknown antigens, in a mouse model of breast cancer (MMTV-Ras. Dendritic cells were evaluated for antigen uptake and for the expression of MHC class I/II and costimulatory molecules and markers associated with maturation.Results showed that antigen-loaded dendritic cells are characterized by a phenotypically semi-mature/mature profile and by the upregulation of genes involved in antigen presentation and T-cell priming. Activated dendritic cells stimulated T-cell proliferation and induced the production of high concentrations of IL-12p70 and IFN-γ but only low levels of IL-10, indicating their ability to elicit a TH1-immune response. Furthermore, administration of Antigen loaded-Dendritic Cells in MMTV-Ras mice evoked a strong anti-tumour response in vivo as demonstrated by a general activation of immunocompetent cells and the release of TH1 cytokines.Data herein could be useful in the design of antitumoral DC-based therapies, showing a specific activation of immune system against breast cancer.

  15. 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.

  16. Tumour tissue microenvironment can inhibit dendritic cell maturation in colorectal cancer.

    Directory of Open Access Journals (Sweden)

    Adriana J Michielsen

    Full Text Available 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.

  17. Tumor Antigen Cross-Presentation and the Dendritic Cell: Where it All Begins?

    Directory of Open Access Journals (Sweden)

    Alison M. McDonnell

    2010-01-01

    Full Text Available Dendritic cells (DCs are professional antigen-presenting cells (APCs that are critical for the generation of effective cytotoxic T lymphocyte (CTL responses; however, their function and phenotype are often defective or altered in tumor-bearing hosts, which may limit their capacity to mount an effective tumor-specific CTL response. In particular, the manner in which exogenous tumor antigens are acquired, processed, and cross-presented to CD8 T cells by DCs in tumor-bearing hosts is not well understood, but may have a profound effect on antitumor immunity. In this paper, we have examined the role of DCs in the cross-presentation of tumor antigen in terms of their subset, function, migration, and location with the intention of examining the early processes that contribute to the development of an ineffective anti-tumor immune response.

  18. 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

  19. T Cells in Osteoarthritis: Alterations and Beyond

    OpenAIRE

    Li, Yu-sheng; Luo, Wei; Zhu, Shou-an; Lei, Guang-hua

    2017-01-01

    Although osteoarthritis (OA) has been traditionally regarded as a non-inflammatory disease, reports increasingly suggest that it is inflammatory, at least in certain patients. OA patients often exhibit inflammatory infiltration of synovial membranes by macrophages, T cells, mast cells, B cells, plasma cells, natural killer cells, dendritic cells, granulocytes, etc. Although previous reviews have summarized the knowledge of inflammation in the pathogenesis of OA, as far as we know, no report r...

  20. 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 andauto... (.csml) Show Plasmacytoid dendritic cells: sensing nucleic acids in viral infection andautoimmune diseases.... PubmedID 18641647 Title Plasmacytoid dendritic cells: sensing nucleic acids in viral infection andauto

  1. 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

  2. Cancer Vaccine by Fusions of Dendritic and Cancer Cells

    Directory of Open Access Journals (Sweden)

    Shigeo Koido

    2009-01-01

    Full Text Available Dendritic cells (DCs are potent antigen-presenting cells and play a central role in the initiation and regulation of primary immune responses. Therefore, their use for the active immunotherapy against cancers has been studied with considerable interest. The fusion of DCs with whole tumor cells represents in many ways an ideal approach to deliver, process, and subsequently present a broad array of tumor-associated antigens, including those yet to be unidentified, in the context of DCs-derived costimulatory molecules. DCs/tumor fusion vaccine stimulates potent antitumor immunity in the animal tumor models. In the human studies, T cells stimulated by DC/tumor fusion cells are effective in lysis of tumor cells that are used as the fusion partner. In the clinical trials, clinical and immunological responses were observed in patients with advanced stage of malignant tumors after being vaccinated with DC/tumor fusion cells, although the antitumor effect is not as vigorous as in the animal tumor models. This review summarizes recent advances in concepts and techniques that are providing new impulses to DCs/tumor fusions-based cancer vaccination.

  3. 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.

  4. Human myeloid dendritic cells are refractory to tryptophan metabolites.

    Science.gov (United States)

    von Bubnoff, Dagmar; Wilms, Helene; Scheler, Marina; Brenk, Manuela; Koch, Susanne; Bieber, Thomas

    2011-10-01

    The enzyme indoleamine 2,3-dioxygenase (IDO) degrades the essential amino acid tryptophan and is expressed, among other cell types, in immune cells such as dendritic cells (DCs), monocytes, and macrophages. It has been shown that the activity of IDO has a broad regulatory function in the immune system by inhibiting effector T-cell responses, inducing regulatory T cells and facilitating the development of regulatory DCs. The degradation of tryptophan has 2 consequences, both of which have been postulated to be physiologically relevant, namely the reduction of tryptophan levels and the accumulation of tryptophan catabolites. Recently, we have shown that DCs that had differentiated under low-tryptophan conditions acquire a tolerogenic phenotype with increased expression of the inhibitory receptors immunoglobulin-like transcript 2 (ILT2), ILT3, and ILT4. In the present study, we investigated the effect of distinct tryptophan catabolites on the function of human DCs and the expression of ILT2, ILT3, and ILT4 on these cells. We show that, in contrast to low tryptophan levels alone, the combination of several metabolites along the tryptophan-kynurenine degradation pathway during DC differentiation does not induce ILT2, ILT3, or ILT4 on these DCs and does not reduce the T-cell stimulatory capacity of these DCs. Copyright © 2011 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

  5. LAG-3 Regulates Plasmacytoid Dendritic Cell Homeostasis1

    Science.gov (United States)

    Workman, Creg J.; Wang, Yao; El Kasmi, Karim C.; Pardoll, Drew M.; Murray, Peter J.; Drake, Charles G.; Vignali, Dario A.A.

    2009-01-01

    LAG-3 is a CD4-related, activation-induced cell surface molecule expressed by various lymphoid cell types and binds to MHC class II with high affinity. We have previously shown that LAG-3 negatively regulates the expansion of activated T cells and T cell homeostasis, and is required for maximal regulatory T cell (Treg) function. Here we demonstrate for the first time that LAG-3 is also expressed on CD11clo/B220+/PDCA-1+ plasmacytoid dendritic cells (pDCs). Lag3 expression, as determined by real time PCR, was ∼10-fold greater in pDCs than in either Tregs or activated T effector cells. Activated pDCs also generate ∼5 times more sLAG-3 than activated T cells. LAG-3-deficient pDCs proliferate and expand more than wild-type pDCs in vivo in response to the TLR9 ligand, CpG. However, the effect of LAG-3 appears to be selective as there was no effect of LAG-3 on the expression of MHC class II, TLR9 and chemokine receptors, or on cytokine production. Lastly, adoptive transfer of either Lag3+/+ or Lag3−/− T cells plus or minus Lag3+/+ or Lag3−/− pDCs defined a role for LAG-3 in controlling pDC homeostasis as well as highlighting the consequences of deregulated Lag3−/− pDCs on T cell homeostasis. This raised the possibility of homeostatic reciprocity between T cells and pDCs. Collectively, our data suggests that LAG-3 plays an important but selective cell intrinsic and cell extrinsic role in pDC biology, and may serve as a key functional marker for their study. PMID:19201841

  6. C-type lectin receptors on dendritic cells and Langerhans cells.

    NARCIS (Netherlands)

    Figdor, C.G.; Kooyk, Y. van; Adema, G.J.

    2002-01-01

    Dendritic cells and Langerhans cells are specialized for the recognition of pathogens and have a pivotal role in the control of immunity. As guardians of the immune system, they are present in essentially every organ and tissue, where they operate at the interface of innate and acquired immunity.

  7. 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

  8. Human XCR1+ dendritic cells derived in vitro from CD34+ progenitors closely resemble blood dendritic cells, including their adjuvant responsiveness, contrary to monocyte-derived dendritic cells.

    Science.gov (United States)

    Balan, Sreekumar; Ollion, Vincent; Colletti, Nicholas; Chelbi, Rabie; Montanana-Sanchis, Frédéric; Liu, Hong; Vu Manh, Thien-Phong; Sanchez, Cindy; Savoret, Juliette; Perrot, Ivan; Doffin, Anne-Claire; Fossum, Even; Bechlian, Didier; Chabannon, Christian; Bogen, Bjarne; Asselin-Paturel, Carine; Shaw, Michael; Soos, Timothy; Caux, Christophe; Valladeau-Guilemond, Jenny; Dalod, Marc

    2014-08-15

    Human monocyte-derived dendritic cell (MoDC) have been used in the clinic with moderately encouraging results. Mouse XCR1(+) DC excel at cross-presentation, can be targeted in vivo to induce protective immunity, and share characteristics with XCR1(+) human DC. Assessment of the immunoactivation potential of XCR1(+) human DC is hindered by their paucity in vivo and by their lack of a well-defined in vitro counterpart. We report in this study a protocol generating both XCR1(+) and XCR1(-) human DC in CD34(+) progenitor cultures (CD34-DC). Gene expression profiling, phenotypic characterization, and functional studies demonstrated that XCR1(-) CD34-DC are similar to canonical MoDC, whereas XCR1(+) CD34-DC resemble XCR1(+) blood DC (bDC). XCR1(+) DC were strongly activated by polyinosinic-polycytidylic acid but not LPS, and conversely for MoDC. XCR1(+) DC and MoDC expressed strikingly different patterns of molecules involved in inflammation and in cross-talk with NK or T cells. XCR1(+) CD34-DC but not MoDC efficiently cross-presented a cell-associated Ag upon stimulation by polyinosinic-polycytidylic acid or R848, likewise to what was reported for XCR1(+) bDC. Hence, it is feasible to generate high numbers of bona fide XCR1(+) human DC in vitro as a model to decipher the functions of XCR1(+) bDC and as a potential source of XCR1(+) DC for clinical use. Copyright © 2014 by The American Association of Immunologists, Inc.

  9. 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.

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

    Science.gov (United States)

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

    2016-12-11

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

  11. 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.

  12. Membrane dynamics and interactions in measles virus dendritic cell infections.

    Science.gov (United States)

    Avota, Elita; Koethe, Susanne; Schneider-Schaulies, Sibylle

    2013-02-01

    Viral entry, compartmentalization and transmission depend on the formation of membrane lipid/protein microdomains concentrating receptors and signalosomes. Dendritic cells (DCs) are prime targets for measles virus (MV) infection, and this interaction promotes immune activation and generalized immunosuppression, yet also MV transport to secondary lymphatics where transmission to T cells occurs. In addition to MV trapping, DC-SIGN interaction can enhance MV uptake by activating cellular sphingomyelinases and, thereby, vertical surface transport of its entry receptor CD150. To exploit DCs as Trojan horses for transport, MV promotes DC maturation accompanied by mobilization, and restrictions of viral replication in these cells may support this process. MV-infected DCs are unable to support formation of functional immune synapses with conjugating T cells and signalling via viral glycoproteins or repulsive ligands (such as semaphorins) plays a key role in the induction of T-cell paralysis. In the absence of antigen recognition, MV transmission from infected DCs to T cells most likely involves formation of polyconjugates which concentrate viral structural proteins, viral receptors and with components enhancing either viral uptake or conjugate stability. Because DCs barely support production of infectious MV particles, these organized interfaces are likely to represent virological synapses essential for MV transmission. © 2012 Blackwell Publishing Ltd.

  13. Immunotherapy Using Dendritic Cells against Multiple Myeloma: How to Improve?

    Directory of Open Access Journals (Sweden)

    Thanh-Nhan Nguyen-Pham

    2012-01-01

    Full Text Available Multiple myeloma (MM is a good target disease in which one can apply cellular immunotherapy, which is based on the graft-versus-myeloma effect. This role of immune effector cells provides the framework for the development of immune-based therapeutic options that use antigen-presenting cells (APCs with increased potency, such as dendritic cells (DCs, in MM. Current isolated idiotype (Id, myeloma cell lysates, myeloma dying cells, DC-myeloma hybrids, or DC transfected with tumor-derived RNA has been used for immunotherapy with DCs. Immunological inhibitory cytokines, such as TGF-β, IL-10, IL-6 and VEGF, which are produced from myeloma cells, can modulate antitumor host immune response, including the abrogation of DC function, by constitutive activation of STAT3. Therefore, even the immune responses have been observed in clinical trials, the clinical response was rarely improved following DC vaccinations in MM patients. We are going to discuss how to improve the efficacy of DC vaccination in MM.

  14. 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...

  15. 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

  16. Efferocytosis promotes suppressive effects on dendritic cells through prostaglandin E2 production in the context of autoimmunity.

    Directory of Open Access Journals (Sweden)

    Irma Pujol-Autonell

    Full Text Available INTRODUCTION: Efferocytosis is a crucial process by which apoptotic cells are cleared by phagocytes, maintaining immune tolerance to self in the absence of inflammation. Peripheral tolerance, lost in autoimmune processes, may be restored by the administration of autologous dendritic cells loaded with islet apoptotic cells in experimental type 1 diabetes. OBJECTIVE: To evaluate tolerogenic properties in dendritic cells induced by the clearance of apoptotic islet cells, thus explaining the re-establishment of tolerance in a context of autoimmunity. METHODS: Bone marrow derived dendritic cells from non-obese diabetic mice, a model of autoimmune diabetes, were generated and pulsed with islet apoptotic cells. The ability of these cells to induce autologous T cell proliferation and to suppress mature dendritic cell function was assessed, together with cytokine production. Microarray experiments were performed using dendritic cells to identify differentially expressed genes after efferocytosis. RESULTS: Molecular and functional changes in dendritic cells after the capture of apoptotic cells were observed. 1 Impaired ability of dendritic cells to stimulate autologous T cell proliferation after the capture of apoptotic cells even after proinflammatory stimuli, with a cytokine profile typical for immature dendritic cells. 2 Suppressive ability of mature dendritic cell function. 3 Microarray-based gene expression profiling of dendritic cells showed differential expression of genes involved in antigen processing and presentation after efferocytosis. 4 Prostaglandin E2 increased production was responsible for immunosuppressive mechanism of dendritic cells after the capture of apoptotic cells. CONCLUSIONS: The tolerogenic behaviour of dendritic cells after islet cells efferocytosis points to a mechanism of silencing potential autoreactive T cells in the microenvironment of autoimmunity. Our results suggest that dendritic cells may be programmed to induce

  17. 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....

  18. New generation of oral mucosal vaccines targeting dendritic cells.

    Science.gov (United States)

    Owen, Jennifer L; Sahay, Bikash; Mohamadzadeh, Mansour

    2013-12-01

    As most infectious organisms gain entry at mucosal surfaces, there is a great deal of interest in developing vaccines that elicit effective mucosal immune responses against pathogen challenge. Targeted vaccination is one of the most effective methods available to prevent and control infectious diseases. Mucosal vaccines can offer lower costs, better accessibility, needle free delivery, and a higher capacity for mass immunizations during pandemics. Both local mucosal immunity and robust systemic responses can be achieved through mucosal vaccination. Recent progress in understanding the molecular and cellular components of the mucosal immune system have allowed for the development of a novel mucosal vaccine platform utilizing specific dendritic cell-targeting peptides and orally administered lactobacilli to elicit efficient antigen specific immune responses against infections, including Bacillus anthracis in experimental models of disease. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. DIFFERENTIAL FUNCTIONAL EFFECTS OF BIOMATERIALS ON DENDRITIC CELL MATURATION

    Science.gov (United States)

    Park, Jaehyung; Babensee, Julia E.

    2012-01-01

    The immunological outcome of dendritic cell (DC) treatment with different biomaterials was assessed to demonstrate the range of DC phenotypes induced by biomaterials commonly used in combination products. Immature DCs (iDCs) were derived from human peripheral blood monocytes, and treated with different biomaterial films of alginate, agarose, chitosan, hyaluronic acid (HA), or 75:25 poly(lactic-co-glycolic acid) (PLGA) and a comprehensive cadre of phenotypic functional outcomes were assessed. Differential levels of functional changes of DC phenotype were observed depending on the type of biomaterial films used to treat DCs. Treatment of DCs with PLGA or chitosan films supported DC maturation with higher levels of DC allostimulatory capacity, pro-inflammatory cytokine release, expression of CD80, CD86, CD83, HLA-DQ and CD44 expression as compared to iDCs, and endocytic ability at a level lower compared to iDCs. Alginate film induced pro-inflammatory cytokine release from DCs at levels higher than iDCs,. Dendritic cells treated with HA film expressed lower levels of CD40, CD80, CD86 and HLA-DR as compared to iDCs. They also exhibited endocytic ability and CD44 expression at levels lower than iDCs, possibly due to an insolublized (cross-linked) form with high molecular weight HA. Interestingly, treatment of DCs with agarose film maintained a DC functional phenotype at levels similar to iDCs except for CD44 expression which was lower than expression levels for iDCs. Taken together, these results can provide selection criteria for biomaterials to be used in immunomodulating applications and can inform potential outcomes of biomaterials within combination products on associated immune responses as desired by the application. PMID:22705044

  20. Mesothelioma Tumor Cells Modulate Dendritic Cell Lipid Content, Phenotype and Function

    Science.gov (United States)

    Gardner, Joanne K.; Mamotte, Cyril D. S.; Patel, Priya; Yeoh, Teong Ling; Jackaman, Connie; Nelson, Delia J.

    2015-01-01

    Dendritic cells (DCs) play an important role in the generation of anti-cancer immune responses, however there is evidence that DCs in cancer patients are dysfunctional. Lipid accumulation driven by tumor-derived factors has recently been shown to contribute to DC dysfunction in several human cancers, but has not yet been examined in mesothelioma. This study investigated if mesothelioma tumor cells and/or their secreted factors promote increases in DC lipid content and modulate DC function. Human monocyte-derived DCs (MoDCs) were exposed to human mesothelioma tumor cells and tumor-derived factors in the presence or absence of lipoproteins. The data showed that immature MoDCs exposed to mesothelioma cells or factors contained increased lipid levels relative to control DCs. Lipid accumulation was associated with reduced antigen processing ability (measured using a DQ OVA assay), upregulation of the co-stimulatory molecule, CD86, and production of the tolerogenic cytokine, IL-10. Increases in DC lipid content were further enhanced by co-exposure to mesothelioma-derived factors and triglyceride-rich lipoproteins, but not low-density lipoproteins. In vivo studies using a murine mesothelioma model showed that the lipid content of tumor-infiltrating CD4+CD8α- DCs, CD4-CD8α- DCs DCs and plasmacytoid DCs increased with tumor progression. Moreover, increasing tumor burden was associated with reduced proliferation of tumor-antigen-specific CD8+ T cells in tumor-draining lymph nodes. This study shows that mesothelioma promotes DC lipid acquisition, which is associated with altered activation status and reduced capacity to process and present antigens, which may impair the ability of DCs to generate effective anti mesothelioma T cell responses. PMID:25886502

  1. Mesothelioma tumor cells modulate dendritic cell lipid content, phenotype and function.

    Directory of Open Access Journals (Sweden)

    Joanne K Gardner

    Full Text Available Dendritic cells (DCs play an important role in the generation of anti-cancer immune responses, however there is evidence that DCs in cancer patients are dysfunctional. Lipid accumulation driven by tumor-derived factors has recently been shown to contribute to DC dysfunction in several human cancers, but has not yet been examined in mesothelioma. This study investigated if mesothelioma tumor cells and/or their secreted factors promote increases in DC lipid content and modulate DC function. Human monocyte-derived DCs (MoDCs were exposed to human mesothelioma tumor cells and tumor-derived factors in the presence or absence of lipoproteins. The data showed that immature MoDCs exposed to mesothelioma cells or factors contained increased lipid levels relative to control DCs. Lipid accumulation was associated with reduced antigen processing ability (measured using a DQ OVA assay, upregulation of the co-stimulatory molecule, CD86, and production of the tolerogenic cytokine, IL-10. Increases in DC lipid content were further enhanced by co-exposure to mesothelioma-derived factors and triglyceride-rich lipoproteins, but not low-density lipoproteins. In vivo studies using a murine mesothelioma model showed that the lipid content of tumor-infiltrating CD4+ CD8α- DCs, CD4- CD8α- DCs DCs and plasmacytoid DCs increased with tumor progression. Moreover, increasing tumor burden was associated with reduced proliferation of tumor-antigen-specific CD8+ T cells in tumor-draining lymph nodes. This study shows that mesothelioma promotes DC lipid acquisition, which is associated with altered activation status and reduced capacity to process and present antigens, which may impair the ability of DCs to generate effective anti mesothelioma T cell responses.

  2. Distribution of Dendritic Cells in Normal Human Salivary Glands

    International Nuclear Information System (INIS)

    Le, An; Saverin, Michele; Hand, Arthur R.

    2011-01-01

    Dendritic cells (DC) are believed to contribute to development of autoimmune sialadenitis, but little is known about their distribution in normal salivary glands. In this study, DC were identified and their distribution was determined in normal human parotid and submandibular glands. For light microscopy, salivary gland sections were stained with H&E or immunocytochemically using antibodies to DC markers. Transmission electron microscopy (TEM) was used to evaluate the ultrastructural characteristics of DC. In H&E sections, elongated, irregularly shaped nuclei were occasionally seen in the striated and excretory duct epithelium. Immunolabeling with anti-HLA-DR, anti-CD11c and anti-S100 revealed DC with numerous processes extending between ductal epithelial cells, often close to the lumen. Morphometric analyses indicated that HLA-DR-positive DC occupied approximately 4–11% of the duct wall volume. Similar reactive cells were present in acini, intercalated ducts and interstitial tissues. TEM observations revealed cells with indented nuclei containing dense chromatin, pale cytoplasm with few organelles, and lacking junctional attachments to adjacent cells. These results indicate that DC are abundant constituents of normal human salivary glands. Their location within ductal and acinar epithelium suggests a role in responding to foreign antigens and/or maintaining immunological tolerance to salivary proteins

  3. Dendritic cell-based vaccine efficacy: aiming for hot spots

    Directory of Open Access Journals (Sweden)

    Gabriela Andrea Pizzurro

    2015-03-01

    Full Text Available Many approaches for cancer immunotherapy have targeted dendritic cells (DC, directly or indirectly, for the induction of antitumor immune responses. DC-based vaccines have been developed using a wide variety of ex vivo DC culture conditions, antigen source and loading strategies, maturation agents and routes of vaccination. Adjuvants are used to activate innate immune cells at the vaccine injection site, to promote antigen transport to the draining lymph nodes (LNs and to model adaptive immune responses. Despite years of effort, the effective induction of strong and durable antitumor T cell responses in vaccinated patients remains a challenge. The study of vaccine interactions with other immune cells in the LNs and, more recently, in the injection site has opened new doors for understanding antitumor effector T cell licensing and function. In this review, we will briefly discuss the relevant sites and up-to-date facts regarding possible targets for antitumor vaccine refinement. We will focus on the processes taking place at the injection site, adjuvant combinations and their role in DC-based vaccines LN homing and modeling vaccine-induced immune responses capable of controlling tumor growth and generating immune memory.

  4. 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.

  5. Critical immunological pathways are downregulated in APECED patient dendritic cells.

    Science.gov (United States)

    Pöntynen, Nora; Strengell, Mari; Sillanpää, Niko; Saharinen, Juha; Ulmanen, Ismo; Julkunen, Ilkka; Peltonen, Leena

    2008-10-01

    Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is a monogenic autoimmune disease caused by mutations in the autoimmune regulator (AIRE) gene. AIRE functions as a transcriptional regulator, and it has a central role in the development of immunological tolerance. AIRE regulates the expression of ectopic antigens in epithelial cells of the thymic medulla and has been shown to participate in the development of peripheral tolerance. However, the mechanism of action of AIRE has remained elusive. To further investigate the role of AIRE in host immune functions, we studied the properties and transcript profiles in in vitro monocyte-differentiated dendritic cells (moDCs) obtained from APECED patients and healthy controls. AIRE-deficient monocytes showed typical DC morphology and expressed DC marker proteins cluster of differentiation 86 and human leukocyte antigen class II. APECED patient-derived moDCs were functionally impaired: the transcriptional response of cytokine genes to pathogens was drastically reduced. Interestingly, some changes were observable already at the immature DC stage. Pathway analyses of transcript profiles revealed that the expression of the components of the host cell signaling pathways involved in cell-cell signalling, innate immune responses, and cytokine activity were reduced in APECED moDCs. Our observations support a role for AIRE in peripheral tolerance and are the first ones to show that AIRE has a critical role in DC responses to microbial stimuli in humans.

  6. Dendritic Cell-Based Immunotherapy Treatment for Glioblastoma Multiforme

    Directory of Open Access Journals (Sweden)

    Liu Yang

    2015-01-01

    Full Text Available Glioblastoma multiforme (GBM is the most malignant glioma and patients diagnosed with this disease had poor outcomes even treated with the combination of conventional treatment (surgery, chemotherapy, and radiation. Dendritic cells (DCs are the most powerful antigen presenting cells and DC-based vaccination has the potential to target and eliminate GBM cells and enhance the responses of these cells to the existing therapies with minimal damage to the healthy tissues around them. It can enhance recognition of GBM cells by the patients’ immune system and activate vast, potent, and long-lasting immune reactions to eliminate them. Therefore, this therapy can prolong the survival of GBM patients and has wide and bright future in the treatment of GBM. Also, the efficacy of this therapy can be strengthened in several ways at some degree: the manipulation of immune regulatory components or costimulatory molecules on DCs; the appropriate choices of antigens for loading to enhance the effectiveness of the therapy; regulation of positive regulators or negative regulators in GBM microenvironment.

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

    Directory of Open Access Journals (Sweden)

    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.

  8. Dendritic compartmentalization of chloride cotransporters underlies directional responses of starburst amacrine cells in retina.

    Science.gov (United States)

    Gavrikov, Konstantin E; Nilson, James E; Dmitriev, Andrey V; Zucker, Charles L; Mangel, Stuart C

    2006-12-05

    The mechanisms in the retina that generate light responses selective for the direction of image motion remain unresolved. Recent evidence indicates that directionally selective light responses occur first in the retina in the dendrites of an interneuron, i.e., the starburst amacrine cell, and that these responses are highly sensitive to the activity of Na-K-2Cl (NKCC) and K-Cl (KCC), two types of chloride cotransporter that determine whether the neurotransmitter GABA depolarizes or hyperpolarizes neurons, respectively. We show here that selective blockade of the NKCC2 and KCC2 cotransporters located on starburst dendrites consistently hyperpolarized and depolarized the starburst cells, respectively, and greatly reduced or eliminated their directionally selective light responses. By mapping NKCC2 and KCC2 antibody staining on these dendrites, we further show that NKCC2 and KCC2 are preferentially located in the proximal and distal dendritic compartments, respectively. Finally, measurements of the GABA reversal potential in different starburst dendritic compartments indicate that the GABA reversal potential at the distal dendrite is more hyperpolarized than at the proximal dendrite due to KCC2 activity. These results thus demonstrate that the differential distribution of NKCC2 on the proximal dendrites and KCC2 on the distal dendrites of starburst cells results in a GABA-evoked depolarization and hyperpolarization at the NKCC2 and KCC2 compartments, respectively, and underlies the directionally selective light responses of the dendrites. The functional compartmentalization of interneuron dendrites may be an important means by which the nervous system encodes complex information at the subcellular level.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  11. SK2 channel modulation contributes to compartment-specific dendritic plasticity in cerebellar Purkinje cells

    Science.gov (United States)

    Ohtsuki, Gen; Piochon, Claire; Adelman, John P.; Hansel, Christian

    2012-01-01

    Small-conductance Ca2+-activated K+ channels (SK channels) modulate excitability and curtail excitatory postsynaptic potentials (EPSPs) in neuronal dendrites. Here, we demonstrate long-lasting plasticity of intrinsic excitability (IE) in dendrites that results from changes in the gain of this regulatory mechanism. Using dendritic patch-clamp recordings from rat cerebellar Purkinje cells, we find that somatic depolarization or parallel fiber (PF) burst stimulation induce long-term amplification of synaptic responses to climbing fiber (CF) or PF stimulation, and enhance the amplitude of passively propagated sodium spikes. Dendritic plasticity is mimicked and occluded by the SK channel blocker apamin, and is absent in Purkinje cells from SK2 null mice. Triple-patch recordings from two dendritic sites and the soma, and confocal calcium imaging studies show that local stimulation limits dendritic plasticity to the activated compartment of the dendrite. This plasticity mechanism allows Purkinje cells to adjust the SK2-mediated control of dendritic excitability in an activity-dependent manner. PMID:22794265

  12. Candida albicans mannoprotein influences the biological function of dendritic cells.

    Science.gov (United States)

    Pietrella, Donatella; Bistoni, Giovanni; Corbucci, Cristina; Perito, Stefano; Vecchiarelli, Anna

    2006-04-01

    Cell wall components of fungi involved in induction of host immune response are predominantly proteins and glycoproteins, the latter being mainly mannoproteins (MP). In this study we analyse the interaction of the MP from Candida albicans (MP65) with dendritic cells (DC) and demonstrate that MP65 stimulates DC and induces the release of TNF-alpha, IL-6 and the activation of IL-12 gene, with maximal value 6 h post treatment. MP65 induces DC maturation by increasing costimulatory molecules and decreasing CD14 and FcgammaR molecule expression. The latter effect is partly mediated by toll-like receptor 2 (TLR2) and TLR4, and the MyD88-dependent pathway is involved in the process. MP65 enables DC to activate T cell response, its protein core is essential for induction of T cell activation, while its glycosylated portion primarily promotes cytokine production. The mechanisms involved in induction of protective response against C. albicans could be mediated by the MP65 antigen, suggesting that MP65 may be a suitable candidate vaccine.

  13. Lipopolysaccharide-induced expression of TRAIL promotes dendritic cell differentiation.

    Science.gov (United States)

    Cho, Young S; Challa, Sreerupa; Clancy, Lauren; Chan, Francis K-M

    2010-08-01

    Tumour necrosis factor-related apoptosis inducing ligand (TRAIL) is a death-inducing cytokine whose physiological function is not well understood. Here, we show that TRAIL has a role in programming human dendritic cell (DC) differentiation. TRAIL expression was strongly induced in DCs upon stimulation with lipopolysaccharide (LPS) or Polyinosine-polycytidylic acid (poly(I:C)) stimulation. Blockade of TRAIL with neutralizing antibody partially inhibited LPS-induced up-regulation of co-stimulatory molecules and the expression of inflammatory cytokines including interleukin-12 (IL-12) p70. In addition, neutralization of TRAIL in LPS-treated DCs inhibited the DC-driven differentiation of T cells into interferon-gamma (IFN-gamma) -producing effectors. The effects of TRAIL neutralization in poly(I:C)-treated DCs were similar, except that IL-12 production and the differentiation of effector T cells into IFN-gamma producers were not inhibited. Strikingly, TRAIL stimulation alone was sufficient to induce morphological changes resembling DC maturation, up-regulation of co-stimulatory molecules, and enhancement of DC-driven allogeneic T-cell proliferation. However, TRAIL alone did not induce inflammatory cytokine production. We further show that the effects of TRAIL on DC maturation were not the result of the induction of apoptosis, but may involve p38 activation. Hence, our data demonstrate that TRAIL co-operates with other cytokines to facilitate DC functional maturation in response to Toll-like receptor activation.

  14. 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.

  15. [Morphofunctional changes of dendritic cells induced by sulfated polysaccharides of brown algae].

    Science.gov (United States)

    Makarenkova, I D; Akhmatova, N K; Ermakova, S P; Besednova, N N

    2017-01-01

    The effects of various sulfated polysaccharides of brown algae Fucus evanescens, Saccharina cichorioides and Saccharina japonica on the morphofunctional changes of dendritic cells have been investigated using flow cytometry and phase-contrast microscopy. The dendritic cells are characterized by larger sizes, vacuolated cytoplasm, eccentrically located nucleus, and also by the presence of numerous cytoplasmic pseudopodia of various shapes. They express surface markers, indicating their maturation (CD83, CD11c, HLA-DR, CD86). Increased production of immunoregulatory (IL-12) and proinflammatory TNF-a, IL-6) cytokines (by dendritic cells polarizes the development of the Th-1 type immune response.

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

    Directory of Open Access Journals (Sweden)

    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.

  17. GABA(B) receptors inhibit backpropagating dendritic spikes in hippocampal CA1 pyramidal cells in vivo.

    Science.gov (United States)

    Leung, L Stan; Peloquin, Pascal

    2006-01-01

    Spike backpropagation has been proposed to enhance dendritic depolarization and synaptic plasticity. However, relatively little is known about the inhibitory control of spike backpropagation in vivo. In this study, the backpropagation of the antidromic spike into the dendrites of CA1 pyramidal cells was studied by extracellular recording in urethane-anesthetized rats. The population antidromic spike (pAS) in CA1 following stimulation of the alveus was recorded simultaneously with a 16-channel silicon probe and analyzed as current source density (CSD). The pAS current sink was shown to sequentially invade the soma and then the apical and basal dendrites. When the pAS was preceded sinks were reduced and delayed. Dendritic spike suppression was large after a high-intensity CA3 conditioning stimulus that evoked a population spike, small after a low-intensity CA3 conditioning stimulus, and weak after conditioning by another pAS. The late (150-400 ms latency) inhibition of the backpropagating pAS at the apical and basal dendrites was partially relieved by a GABA(B) receptor antagonist, CGP35348 or CGP56999A, given intracerebroventricularly (icv). CGP35348 icv also decreased the latency of the antidromic spike sinks at all depths. A compartment cable model of a CA1 pyramidal cell with excitable dendrites, combined with a model of extracellular potential generation, confirms that GABA(B) receptor activation delays a backpropagating spike and blocks distal dendritic spikes. GABA(B) receptor-mediated conductance increase and hyperpolarization, amplified by removing dendritic I(A) inactivation, contribute to conditioned dendritic spike suppression. In addition, the model shows that slow Na(+) channel inactivation also participates in conditioned spike suppression, which may partly explain the small dendritic spike suppression after conditioning with a weak orthodromic stimulus or another antidromic spike. Thus, both theory and experiment confirm an important role of the GABA

  18. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Schwarz, Sebastian [Institute for Biomedical Engineering, Department of Cell Biology, RWTH Aachen University Medical School, Pauwelsstrasse 30, 52074 Aachen (Germany); Helmholtz Institute for Biomedical Engineering, Department of Cell Biology, RWTH Aachen, Pauwelsstrasse 20, 52074 Aachen (Germany); Fernandes, Fabiana [Institute for Biomedical Engineering, Department of Cell Biology, RWTH Aachen University Medical School, Pauwelsstrasse 30, 52074 Aachen (Germany); Department of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Sanroman, Laura [Institute for Biomedical Engineering, Department of Cell Biology, RWTH Aachen University Medical School, Pauwelsstrasse 30, 52074 Aachen (Germany); Helmholtz Institute for Biomedical Engineering, Department of Cell Biology, RWTH Aachen, Pauwelsstrasse 20, 52074 Aachen (Germany); Hodenius, Michael [Institute for Biomedical Engineering and Helmholtz Institute for Biomedical Engineering, Department of Applied Medical Engineering, RWTH Aachen, Pauwelsstrasse 20, 52074 Aachen (Germany); Lang, Claus [Department of Microbiology, Ludwig-Maximillians-University of Munich, Maria-Ward-Str. 1a, 80638 Munich (Germany); Himmelreich, Uwe [In-vivo-NMR-Laboratory, Max-Planck-Institute for Neurological Research, Gleueler Str. 50, 50931 Cologne (Germany); Biomedical NMR Unit, MoSAIC, Faculty of Medicine, KU Leuven, Onderwijs en Navorsing 1, bus 505, 3000 Leuven (Belgium); Schmitz-Rode, Thomas [Institute for Biomedical Engineering and Helmholtz Institute for Biomedical Engineering, Department of Applied Medical Engineering, RWTH Aachen, Pauwelsstrasse 20, 52074 Aachen (Germany); Schueler, Dirk [Department of Microbiology, Ludwig-Maximillians-University of Munich, Maria-Ward-Str. 1a, 80638 Munich (Germany); Hoehn, Mathias [In-vivo-NMR-Laboratory, Max-Planck-Institute for Neurological Research, Gleueler Str. 50, 50931 Cologne (Germany)] (and others)

    2009-05-15

    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{sup +} 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.

  20. 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.

  1. Loss of Gadkin Affects Dendritic Cell Migration In Vitro.

    Directory of Open Access Journals (Sweden)

    Hannah Schachtner

    Full Text Available Migration is crucial for the function of dendritic cells (DCs, which act as outposts of the immune system. Upon detection of pathogens, skin- and mucosa-resident DCs migrate to secondary lymphoid organs where they activate T cells. DC motility relies critically on the actin cytoskeleton, which is regulated by the actin-related protein 2/3 (ARP2/3 complex, a nucleator of branched actin networks. Consequently, loss of ARP2/3 stimulators and upstream Rho family GTPases dramatically impairs DC migration. However, nothing is known yet about the relevance of ARP2/3 inhibitors for DC migration. We previously demonstrated that the AP-1-associated adaptor protein Gadkin inhibits ARP2/3 by sequestering it on intracellular vesicles. Consistent with a role of Gadkin in DC physiology, we here report Gadkin expression in bone marrow-derived DCs and show that its protein level and posttranslational modification are regulated upon LPS-induced DC maturation. DCs derived from Gadkin-deficient mice were normal with regards to differentiation and maturation, but displayed increased actin polymerization. While the actin-dependent processes of macropinocytosis and cell spreading were not affected, loss of Gadkin significantly impaired DC migration in vitro, however, in vivo DC migration was unperturbed suggesting the presence of compensatory mechanisms.

  2. Intestinal dendritic cells in the regulation of mucosal immunity

    DEFF Research Database (Denmark)

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

    2014-01-01

    The intestine presents a huge surface area to the outside environment, a property that is of critical importance for its key functions in nutrient digestion, absorption, and waste disposal. As such, the intestine is constantly exposed to dietary and microbial-derived foreign antigens, to which im...... of the role these subsets play in the regulation of intestinal immune homeostasis and inflammation will help to define novel strategies for the treatment of intestinal pathologies and contribute to improved rational design of mucosal vaccines....... 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...... immune responses. In the intestinal mucosa, DCs are located diffusely throughout the intestinal lamina propria, within gut-associated lymphoid tissues, including Peyer's patches and smaller lymphoid aggregates, as well as in intestinal-draining lymph nodes, including mesenteric lymph nodes...

  3. Overview of dendritic cell-based vaccine development for leishmaniasis.

    Science.gov (United States)

    Bagirova, M; Allahverdiyev, A M; Abamor, E S; Ullah, I; Cosar, G; Aydogdu, M; Senturk, H; Ergenoglu, B

    2016-11-01

    Leishmaniasis is one of the most serious vector-borne diseases in the world and is distributed over 98 countries. It is estimated that 350 million people are at risk for leishmaniasis. There are three different generation of vaccines that have been developed to provide immunity and protection against leishmaniasis. However, their use has been limited due to undesired side effects. These vaccines have also failed to provide effective and reliable protection and, as such, currently, there is no safe and effective vaccine for leishmaniasis. Dendritic cells (DCs) are a unique population of cells that come from bone marrow and become specialized to take up, process and present antigens to helper T cells in a mechanism similar to macrophages. By considering these significant features, DCs stimulated with different kinds of Leishmania antigens have been used in recent vaccine studies for leishmaniasis with promising results so far. In this review, we aim to review and combine the latest studies about this issue after defining potential problems in vaccine development for leishmaniasis and considering the importance of DCs in the immunopathogenesis of the disease. © 2016 John Wiley & Sons Ltd.

  4. Interaction of large DNA viruses with dendritic cells.

    Science.gov (United States)

    Jenne, L; Thumann, P; Steinkasserer, A

    2001-12-01

    Dendritic cells (DC) with their unique capacity to prime naïve T cells are crucial in the induction of immunological responses, including anti-tumoral and anti-viral immunity. DC based immunotherapies are thus currently considered a particularly promising approach for cellular immunotherapy. The cloning of tumor associated antigens (TAAs) together with the possibility of manipulating viral genomes by biotechnological techniques has sparked the interest of using genetically modified viruses to transduce DC in order to achieve antigenic expression of TAA with the aim of inducing a protective immune response. An increasing number of modified viral vectors has been designed for gene therapy purposes and consecutively has been used for the ex vivo transduction of DC. It has been shown that viral vectors genetically engineered to express TAA or immune modifiers like cytokines or costimulatory molecules can lead to a high level of transgene expression. Furthermore, these studies have also revealed that viruses have developed several immune evasion mechanisms specifically targeting DC. Therefore, analysing the interactions of viruses with DC is crucial for the development of new viral vectors suitable for the transduction of DC. In this report we describe the interaction of two large DNA viruses, herpes simplex virus type 1 (HSV-1) and vaccinia virus (VV), with DC generated from peripheral blood mononuclear cells.

  5. 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.

  6. 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.

  7. Bisphenol-A exposure during adolescence leads to enduring alterations in cognition and dendritic spine density in adult male and female rats.

    Science.gov (United States)

    Bowman, Rachel E; Luine, Victoria; Diaz Weinstein, Samantha; Khandaker, Hameda; DeWolf, Sarah; Frankfurt, Maya

    2015-03-01

    We have previously demonstrated that adolescent exposure of rats to bisphenol-A (BPA), an environmental endocrine disrupter, increases anxiety, impairs spatial memory, and decreases dendritic spine density in the CA1 region of the hippocampus (CA1) and medial prefrontal cortex (mPFC) when measured in adolescents in both sexes. The present study examined whether the behavioral and morphological alterations following BPA exposure during adolescent development are maintained into adulthood. Male and female, adolescent rats received BPA, 40μg/kg/bodyweight, or control treatments for one week. In adulthood, subjects were tested for anxiety and locomotor activity, spatial memory, non-spatial visual memory, and sucrose preference. Additionally, stress-induced serum corticosterone levels and dendritic spine density in the mPFC and CA1 were measured. BPA-treated males, but not females, had decreased arm visits on the elevated plus maze, but there was no effect on anxiety. Non-spatial memory, object recognition, was also decreased in BPA treated males, but not in females. BPA exposure did not alter spatial memory, object placement, but decreased exploration during the tasks in both sexes. No significant group differences in sucrose preference or serum corticosterone levels in response to a stress challenge were found. However, BPA exposure, regardless of sex, significantly decreased spine density of both apical and basal dendrites on pyramidal cells in CA1 but had no effect in the mPFC. Current data are discussed in relation to BPA dependent changes, which were present during adolescence and did, or did not, endure into adulthood. Overall, adolescent BPA exposure, below the current reference safe daily limit set by the U.S.E.P.A., leads to alterations in some behaviors and neuronal morphology that endure into adulthood. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. 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...... dependent DCs in the maintenance of intestinal T cell homeostasis....

  9. Differential Regulation of Apical-basolateral Dendrite Outgrowth by Activity in Hippocampal Neurons

    Directory of Open Access Journals (Sweden)

    Yang eYuan

    2015-08-01

    Full Text Available Hippocampal pyramidal neurons have characteristic dendrite asymmetry, characterized by structurally and functionally distinct apical and basolateral dendrites. The ability of the neuron to generate and maintain dendrite asymmetry is vital, since synaptic inputs received are critically dependent on dendrite architecture. Little is known about the role of neuronal activity in guiding maintainance of dendrite asymmetry. Our data indicate that dendrite asymmetry is established and maintained early during development. Further, our results indicate that cell intrinsic and global alterations of neuronal activity have differential effects on net extension of apical and basolateral dendrites. Thus, apical and basolateral dendrite extension may be independently regulated by cell intrinsic and network neuronal activity during development, suggesting that individual dendrites may have autonomous control over net extension. We propose that regulated individual dendrite extension in response to cell intrinsic and neuronal network activity may allow temporal control of synapse specificity in the developing hippocampus.

  10. Dendritic spine remodeling after spinal cord injury alters neuronal signal processing.

    Science.gov (United States)

    Tan, Andrew M; Choi, Jin-Sung; Waxman, Stephen G; Hains, Bryan C

    2009-10-01

    Central sensitization, a prolonged hyperexcitability of dorsal horn nociceptive neurons, is a major contributor to abnormal pain processing after spinal cord injury (SCI). Dendritic spines are micron-sized dendrite protrusions that can regulate the efficacy of synaptic transmission. Here we used a computational approach to study whether changes in dendritic spine shape, density, and distribution can individually, or in combination, adversely modify the input-output function of a postsynaptic neuron to create a hyperexcitable neuronal state. The results demonstrate that a conversion from thin-shaped to more mature, mushroom-shaped spine structures results in enhanced synaptic transmission and fidelity, improved frequency-following ability, and reduced inhibitory gating effectiveness. Increasing the density and redistributing spines toward the soma results in a greater probability of action potential activation. Our results demonstrate that changes in dendritic spine morphology, documented in previous studies on spinal cord injury, contribute to the generation of pain following SCI.

  11. 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.

  12. 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

  13. 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.

  14. Evidence for local dendritic cell activation in pulmonary sarcoidosis

    Directory of Open Access Journals (Sweden)

    Berge Bregje

    2012-04-01

    Full Text Available Abstract Background Sarcoidosis is a granulomatous disease characterized by a seemingly exaggerated immune response against a difficult to discern antigen. Dendritic cells (DCs are pivotal antigen presenting cells thought to play an important role in the pathogenesis. Paradoxically, decreased DC immune reactivity was reported in blood samples from pulmonary sarcoidosis patients. However, functional data on lung DCs in sarcoidosis are lacking. We hypothesized that at the site of disease DCs are mature, immunocompetent and involved in granuloma formation. Methods We analyzed myeloid DCs (mDCs and plasmacytoid DCs (pDCs in broncho-alveolar lavage (BAL and blood from newly diagnosed, untreated pulmonary sarcoidosis patients and healthy controls using 9-color flowcytometry. DCs, isolated from BAL using flowcytometric sorting (mDCs or cultured from monocytes (mo-DCs, were functionally assessed in a mixed leukocyte reaction with naïve allogeneic CD4+ T cells. Using Immunohistochemistry, location and activation status of CD11c+DCs was assessed in mucosal airway biopsies. Results mDCs in BAL, but not in blood, from sarcoidosis patients were increased in number when compared with mDCs from healthy controls. mDCs purified from BAL of sarcoidosis patients induced T cell proliferation and differentiation and did not show diminished immune reactivity. Mo-DCs from patients induced increased TNFα release in co-cultures with naïve allogeneic CD4+ T cells. Finally, immunohistochemical analyses revealed increased numbers of mature CD86+ DCs in granuloma-containing airway mucosal biopsies from sarcoidosis patients. Conclusion Taken together, these finding implicate increased local DC activation in granuloma formation or maintenance in pulmonary sarcoidosis.

  15. Dendritic Cell-Based Immunotherapy for Myeloid Leukemias

    Science.gov (United States)

    Schürch, Christian M.; Riether, Carsten; Ochsenbein, Adrian F.

    2013-01-01

    Acute and chronic myeloid leukemia (AML, CML) are hematologic malignancies arising from oncogene-transformed hematopoietic stem/progenitor cells known as leukemia stem cells (LSCs). LSCs are selectively resistant to various forms of therapy including irradiation or cytotoxic drugs. The introduction of tyrosine kinase inhibitors has dramatically improved disease outcome in patients with CML. For AML, however, prognosis is still quite dismal. Standard treatments have been established more than 20 years ago with only limited advances ever since. Durable remission is achieved in less than 30% of patients. Minimal residual disease (MRD), reflected by the persistence of LSCs below the detection limit by conventional methods, causes a high rate of disease relapses. Therefore, the ultimate goal in the treatment of myeloid leukemia must be the eradication of LSCs. Active immunotherapy, aiming at the generation of leukemia-specific cytotoxic T cells (CTLs), may represent a powerful approach to target LSCs in the MRD situation. To fully activate CTLs, leukemia antigens have to be successfully captured, processed, and presented by mature dendritic cells (DCs). Myeloid progenitors are a prominent source of DCs under homeostatic conditions, and it is now well established that LSCs and leukemic blasts can give rise to “malignant” DCs. These leukemia-derived DCs can express leukemia antigens and may either induce anti-leukemic T cell responses or favor tolerance to the leukemia, depending on co-stimulatory or -inhibitory molecules and cytokines. This review will concentrate on the role of DCs in myeloid leukemia immunotherapy with a special focus on their generation, application, and function and how they could be improved in order to generate highly effective and specific anti-leukemic CTL responses. In addition, we discuss how DC-based immunotherapy may be successfully integrated into current treatment strategies to promote remission and potentially cure myeloid leukemias

  16. 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.

  17. Dendritic Cells and Multiple Sclerosis: Disease, Tolerance and Therapy

    Directory of Open Access Journals (Sweden)

    Mohammad G. Mohammad

    2012-12-01

    Full Text Available Multiple sclerosis (MS is a devastating neurological disease that predominantly affects young adults resulting in severe personal and economic impact. The majority of therapies for this disease were developed in, or are beneficial in experimental autoimmune encephalomyelitis (EAE, the animal model of MS. While known to target adaptive anti-CNS immune responses, they also target, the innate immune arm. This mini-review focuses on the role of dendritic cells (DCs, the professional antigen presenting cells of the innate immune system. The evidence for a role for DCs in the appropriate regulation of anti-CNS autoimmune responses and their role in MS disease susceptibility and possible therapeutic utility are discussed. Additionally, the current controversy regarding the evidence for the presence of functional DCs in the normal CNS is reviewed. Furthermore, the role of CNS DCs and potential routes of their intercourse between the CNS and cervical lymph nodes are considered. Finally, the future role that this nexus between the CNS and the cervical lymph nodes might play in site directed molecular and cellular therapy for MS is outlined.

  18. 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.

  19. Neuropeptide Y induces potent migration of human immature dendritic cells and promotes a Th2 polarization.

    Science.gov (United States)

    Buttari, Brigitta; Profumo, Elisabetta; Domenici, Giacomo; Tagliani, Angela; Ippoliti, Flora; Bonini, Sergio; Businaro, Rita; Elenkov, Ilia; Riganò, Rachele

    2014-07-01

    Neuropeptide Y (NPY), a major autonomic nervous system and stress mediator, is emerging as an important regulator of inflammation, implicated in autoimmunity, asthma, atherosclerosis, and cancer. Yet the role of NPY in regulating phenotype and functions of dendritic cells (DCs), the professional antigen-presenting cells, remains undefined. Here we investigated whether NPY could induce DCs to migrate, mature, and polarize naive T lymphocytes. We found that NPY induced a dose-dependent migration of human monocyte-derived immature DCs through the engagement of NPY Y1 receptor and the activation of ERK and p38 mitogen-activated protein kinases. NPY promoted DC adhesion to endothelial cells and transendothelial migration. It failed to induce phenotypic DC maturation, whereas it conferred a T helper 2 (Th2) polarizing profile to DCs through the up-regulation of interleukin (IL)-6 and IL-10 production. Thus, during an immune/inflammatory response NPY may exert proinflammatory effects through the recruitment of immature DCs, but it may exert antiinflammatory effects by promoting a Th2 polarization. Locally, at inflammatory sites, cell recruitment could be amplified in conditions of intense acute, chronic, or cold stress. Thus, altered or amplified signaling through the NPY-NPY-Y1 receptor-DC axis may have implications for the development of inflammatory conditions.-Buttari, B., Profumo, E., Domenici, G., Tagliani, A., Ippoliti, F., Bonini, S., Businaro, R., Elenkov, I., Riganò, R. Neuropeptide Y induces potent migration of human immature dendritic cells and promotes a Th2 polarization. © FASEB.

  20. Dendritic relationship between starburst amacrine cells and direction-selective ganglion cells in the rabbit retina.

    Science.gov (United States)

    Dong, Wei; Sun, Wenzhi; Zhang, Yingye; Chen, Xiaorong; He, Shigang

    2004-04-01

    We investigated the dendritic relationship between starburst amacrine cells (SAs) and morphologically and physiologically characterized ON and ON-OFF direction-selective ganglion cells (DSGCs) in the rabbit retina. ON and ON-OFF DSGCs were found to exhibit tight dendritic cofasciculation with the SA plexus, visualized by immunolabelling of the vesicular acetylcholine transporter (VAChT). The degree of cofasciculation of both types of DSGC dendrites and SA plexus was found to be significant, unlike the relationship between non-DS cells and the SA plexus, which was close to chance distribution. No difference in the degree of cofasciculation in different regions of the DS dendritic field was observed. Individual SAs intracellularly injected both on the 'preferred' and 'null' side of the DSGCs showed the same degree of cofasciculation with the DSGCs. Therefore, the computation of motion direction is unlikely to result from apparent asymmetry in geometric proximity between SAs and DSGCs. Highly selective synaptic connections between SAs and DSGCs are necessary.

  1. Dendritic Cell-Targeted Phage Vectors for Breast Cancer Vaccine Development

    National Research Council Canada - National Science Library

    Dewhurst, Stephen

    2002-01-01

    .... During the period covered by this progress report, we have used phage display technology to identify peptide sequences which bind to cellular receptors expressed on dendritic cells, and we have...

  2. 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

  3. 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.

  4. 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.

  5. 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

  6. Resistin-like molecule alpha1 (Fizz1 recruits lung dendritic cells without causing pulmonary fibrosis

    Directory of Open Access Journals (Sweden)

    Madala Satish K

    2012-06-01

    Full Text Available Abstract Background Resistin-like molecule alpha or found in inflammatory zone protein (Fizz1 is increased in pulmonary epithelial cells and also in limited amounts by other lung cells during various lung injuries and fibrosis. However, the direct role of Fizz1 produced in the pulmonary epithelium has not been determined. Methods Fizz1 Transgenic mice (CCSP/Fizz1 were generated that overexpress Fizz1 in the lung epithelium under the control of a doxycycline (Dox inducible lung epithelial cell specific promoter Scgb1a1 (Clara cell secretory protein, CCSP. Histology and FACS analysis of lung cells were used to identify the direct effects of Fizz1 in the transgenic mice (Dox treated when compared with control (CCSP/- mice. Intratracheal bleomycin sulfate or silica in saline and saline alone were used to study the role of Fizz1 during bleomycin- and silica-induced pulmonary fibrosis in CCSP/Fizz1 and CCSP/- mice. Weight change, pulmonary inflammation, and fibrosis were assessed 10 days post bleomycin or 28 days post silica challenge. Results When CCSP/Fizz1 mice were fed Dox food, elevated Fizz1 protein was detected in lung homogenates by western blot. Lungs of mice in which Fizz1 was induced in the epithelium contained increased lung cells staining for CD11c and F4/80 by FACS analysis consistent with increased dendritic cells however, no changes were observed in the percentage of interstitial macrophages compared to CCSP/- controls. No significant changes were found in the lung histology of CCSP/Fizz1 mice after up to 8 weeks of overexpression compared to CCSP/- controls. Overexpression of Fizz1 prior to challenge or following challenge with bleomycin or silica did not significantly alter airway inflammation or fibrosis compared to control mice. Conclusions The current study demonstrates that epithelial cell derived Fizz1 is sufficient to increase the bone-marrow derived dendritic cells in the lungs, but it is not sufficient to cause lung

  7. Symmetric interactions within a homogeneous starburst cell network can lead to robust asymmetries in dendrites of starburst amacrine cells.

    Science.gov (United States)

    Münch, Thomas A; Werblin, Frank S

    2006-07-01

    Starburst amacrine cells in the mammalian retina respond asymmetrically to movement along their dendrites; centrifugal movement elicits stronger responses in each dendrite than centripetal movement. It has been suggested that the asymmetrical response can be attributed to intrinsic properties of the processes themselves. But starburst cells are known to release and have receptors for both GABA and acetylcholine. We tested whether interactions within the starburst cell network can contribute to their directional response properties. In a computational model of interacting starburst amacrine cells, we simulated the response of individual dendrites to moving light stimuli. By setting the model parameters for "synaptic connection strength" (cs) to positive or negative values, overlapping starburst dendrites could either excite or inhibit each other. For some values of cs, we observed a very robust inward/outward asymmetry of the starburst dendrites consistent with the reported physiological findings. This is the case, for example, if a starburst cell receives inhibition from other starburst cells located in its surround. For other values of cs, individual dendrites can respond best either to inward movement or respond symmetrically. A properly wired network of starburst cells can therefore account for the experimentally observed asymmetry of their response to movement, independent of any internal biophysical or biochemical properties of starburst cell dendrites.

  8. Modulation of respiratory dendritic cells during Klebsiella pneumonia infection

    Science.gov (United States)

    2013-01-01

    Background Klebsiella pneumoniae is a leading cause of severe hospital-acquired respiratory tract infections and death but little is known regarding the modulation of respiratory dendritic cell (DC) subsets. Plasmacytoid DC (pDC) are specialized type 1 interferon producing cells and considered to be classical mediators of antiviral immunity. Method By using multiparameter flow cytometry analysis we have analysed the modulation of respiratory DC subsets after intratracheal Klebsiella pneumonia infection. Results Data indicate that pDCs and MoDC were markedly elevated in the post acute pneumonia phase when compared to mock-infected controls. Analysis of draining mediastinal lymph nodes revealed a rapid increase of activated CD103+ DC, CD11b+ DC and MoDC within 48 h post infection. Lung pDC identification during bacterial pneumonia was confirmed by extended phenotyping for 120G8, mPDCA-1 and Siglec-H expression and by demonstration of high Interferon-alpha producing capacity after cell sorting. Cytokine expression analysis of ex vivo-sorted respiratory DC subpopulations from infected animals revealed elevated Interferon-alpha in pDC, elevated IFN-gamma, IL-4 and IL-13 in CD103+ DC and IL-19 and IL-12p35 in CD11b+ DC subsets in comparison to CD11c+ MHC-class IIlow cells indicating distinct functional roles. Antigen-specific naive CD4+ T cell stimulatory capacity of purified respiratory DC subsets was analysed in a model system with purified ovalbumin T cell receptor transgenic naive CD4+ responder T cells and respiratory DC subsets, pulsed with ovalbumin and matured with Klebsiella pneumoniae lysate. CD103+ DC and CD11b+ DC subsets represented the most potent naive CD4+ T helper cell activators. Conclusion These results provide novel insight into the activation of respiratory DC subsets during Klebsiella pneumonia infection. The detection of increased respiratory pDC numbers in bacterial pneumonia may indicate possible novel pDC functions with respect to lung repair

  9. 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.

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

    DEFF Research Database (Denmark)

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

    2009-01-01

    Pseudomonas aeruginosa releases a wide array of toxins and tissue-degrading enzymes. Production of these malicious virulence factors is controlled by interbacterial communication in a process known as quorum sensing. An increasing body of evidence reveals that the bacterial signal molecule N-(3...... article we demonstrate that both OdDHL and PQS decrease the production of interleukin-12 (IL-12) by Escherichia coli lipopolysaccharide-stimulated bone marrow-derived dendritic cells (BM-DCs) without altering their IL-10 release. Moreover, BM-DCs exposed to PQS and OdDHL during antigen stimulation exhibit...... a decreased ability to induce T-cell proliferation in vitro. Collectively, this suggests that OdDHL and PQS change the maturation pattern of stimulated DCs away from a proinflammatory T-helper type I directing response, thereby decreasing the antibacterial activity of the adaptive immune defence. Od...

  11. 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.

  12. BAFF and APRIL from Activin A-Treated Dendritic Cells Upregulate the Antitumor Efficacy of Dendritic Cells In Vivo.

    Science.gov (United States)

    Shurin, Michael R; Ma, Yang; Keskinov, Anton A; Zhao, Ruijing; Lokshin, Anna; Agassandian, Marianna; Shurin, Galina V

    2016-09-01

    The members of the TGFβ superfamily play a key role in regulating developmental and homeostasis programs by controlling differentiation, proliferation, polarization, and survival of different cell types. Although the role of TGFβ1 in inflammation and immunity is well evident, the contribution of other TGFβ family cytokines in the modulation of the antitumor immune response remains less documented. Here we show that activin A triggers SMAD2 and ERK1/2 pathways in dendritic cells (DC) expressing type I and II activin receptors, and upregulates production of the TNFα family cytokines BAFF (TALL-1, TNFSF13B) and APRIL (TALL-2, TNFSF13A), which is blocked by SMAD2 and ERK1/2 inhibitors, respectively. BAFF and APRIL derived from activin A-treated DCs upregulate proliferation and survival of T cells expressing the corresponding receptors, BAFF-R and TACI. In vivo, activin A-stimulated DCs demonstrate a significantly increased ability to induce tumor-specific CTLs and inhibit the growth of melanoma and lung carcinoma, which relies on DC-derived BAFF and APRIL, as knockdown of the BAFF and APRIL gene expression in activin A-treated DCs blocks augmentation of their antitumor potential. Although systemic administration of activin A, BAFF, or APRIL for the therapeutic purposes is not likely due to the pluripotent effects on malignant and nonmalignant cells, our data open a novel opportunity for improving the efficacy of DC vaccines. In fact, a significant augmentation of the antitumor activity of DC pretreated with activin A and the proven role of DC-derived BAFF and APRIL in the induction of antitumor immunity in vivo support this direction. Cancer Res; 76(17); 4959-69. ©2016 AACR. ©2016 American Association for Cancer Research.

  13. 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.

  14. Natural Killer cells as helper cells in Dendritic cell cancer vaccines

    Directory of Open Access Journals (Sweden)

    María Betina Pampena

    2015-01-01

    Full Text Available Vaccine-based cancer immunotherapy has generated highly variable clinical results due to differing methods of vaccine preparation and variation in patient populations, among other lesser factors. Moreover, these clinical responses do not necessarily correspond with the induction of tumor-specific cytotoxic lymphocytes. Here we review the participation of natural killer (NK cells as alternative immune components that could cooperate in successful vaccination treatment. NK cells have been described as helper cells in dendritic cell-based cancer vaccines, but the role in other kinds of vaccination strategies (whole cells, peptide or DNA- based vaccines is poorly understood. In this article we address the following issues regarding the role of NK cells in cancer vaccines: NK cell anti-tumor action sites, and the loci of NK cell interaction with other immune cells; descriptions of new data on the memory characteristics of NK cells described in infectious diseases; and finally phenotypical and functional changes after vaccination measured by immunomonitoring in preclinical and clinical settings.

  15. Human Liver Stem Cells Suppress T-Cell Proliferation, NK Activity, and Dendritic Cell Differentiation

    Directory of Open Access Journals (Sweden)

    Stefania Bruno

    2016-01-01

    Full Text Available Human liver stem cells (HLSCs are a mesenchymal stromal cell-like population resident in the adult liver. Preclinical studies indicate that HLSCs could be a good candidate for cell therapy. The aim of the present study was to evaluate the immunogenicity and the immunomodulatory properties of HLSCs on T-lymphocytes, natural killer cells (NKs, and dendritic cells (DCs in allogeneic experimental settings. We found that HLSCs inhibited T-cell proliferation by a mechanism independent of cell contact and dependent on the release of prostaglandin E2 (PGE2 and on indoleamine 2,3-dioxygenase activity. When compared with mesenchymal stromal cells (MSCs, HLSCs were more efficient in inhibiting T-cell proliferation. At variance with MSCs, HLSCs did not elicit NK degranulation. Moreover, HLSCs inhibited NK degranulation against K562, a NK-sensitive target, by a mechanism dependent on HLA-G release. When tested on DC generation from monocytes, HLSCs were found to impair DC differentiation and DCs ability to induce T-cell proliferation through PGE2. This study shows that HLSCs have immunomodulatory properties similar to MSCs, but, at variance with MSCs, they do not elicit a NK response.

  16. Enhancing whole-tumor cell vaccination by engaging innate immune system through NY-ESO-1/dendritic cell interactions.

    Science.gov (United States)

    Xu, Le; Zheng, Junying; Nguyen, David H; Luong, Quang T; Zeng, Gang

    2013-10-01

    NY-ESO-1 is a cancer/germline antigen (Ag) with distinctively strong immunogenicity. We have previously demonstrated that NY-ESO-1 serves as an endogenous adjuvant by engaging dendritic cell (DC)-surface receptors of calreticulin (CRT) and toll-like receptor (TLR) 4. In the present study, NY-ESO-1 was investigated for its immunomodulatory roles as a molecular adjuvant in whole-tumor cell vaccines using the Renca kidney cancer model. Renca cells were genetically engineered to express NY-ESO-1 on the cell surface to enhance direct interactions with DC. The effect of ectopic cell-surface expression of NY-ESO-1 was investigated on tumor immunogenicity, DC activation, cytotoxic T lymphocytes against model tumor-associated Ags, and the effectiveness of the modified tumor cells as a therapeutic whole-cell vaccine. Cell-surface expression of NY-ESO-1 was able to reduce the tumor growth of Renca cells in BALB/c mice, although the modification did not alter cell proliferation rate in vitro. Directly engaging the innate immune system through NY-ESO-1 facilitated the interaction of tumor cells with DC, leading to enhanced DC activation and subsequent tumor-specific T-cell priming. When used as a therapeutic whole-cell vaccine, Renca cells with NY-ESO-1 on the surface mediated stronger inhibitory effects on tumor growth and metastasis compared with parental Renca or Renca cells expressing a control protein GFP on the surface. Augmented antitumor efficacy correlated with increased CD8 T-cell infiltration into tumors and decreased myeloid-derived suppressor cells and regulatory T cells in the spleen. As a cancer/germline Ag and as an immunomodulatory adjuvant through engaging innate immune receptors, NY-ESO-1 offers a unique opportunity for improved whole-tumor cell vaccinations upon the classic GM-CSF-engineered cell vaccines.

  17. Nanostructured lipid carriers loaded with resveratrol modulate human dendritic cells

    Directory of Open Access Journals (Sweden)

    Barbosa JP

    2016-07-01

    Full Text Available João P Barbosa,1–3,* Ana R Neves,3,* Andreia M Silva,1,2,4 Mário A Barbosa,1,2,4 M Salette Reis,3 Susana G Santos1,2 1Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal; 2INEB - Instituto de Engenharia Biomédica, Universidade do Porto, Portugal; 3UCIBIO, REQUIMTE, Chemical Sciences Department, Faculty of Pharmacy, University of Porto, Portugal; 4Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal *These authors contributed equally to this work Abstract: Dendritic cells (DCs are promising targets for drug delivery, as they can induce immunity or tolerance. The current study aims to examine the potential of using nanostructured lipid carriers (NLC as delivery systems for human DC by evaluating nanoparticle internalization, cell labeling, and drug activity. NLC were formulated incorporating the fluorochrome fluorescein isothiocyanate (FITC-NLC or the natural anti-inflammatory molecule resveratrol (rsv-NLC. Primary human DCs were differentiated from peripheral blood monocytes, and the innovative imaging flow cytometry technique was used to examine FITC-NLC internalization. The capacity of rsv-NLC to inhibit DC activation in response to proinflammatory cytokine tumor necrosis factor-α (TNF-α was investigated by conventional flow cytometry. A combination of imaging and conventional flow cytometry was used to assess NLC cytotoxicity. The results obtained indicate that both NLC formulations were stable over time, with mean diameter <200 nm and highly negative zeta potential (about -30 mV. When DCs were placed in contact with NLC, imaging flow cytometry clearly showed that DCs efficiently internalized FITC-NLC, with nearly 100% of cells internalizing nanoparticles upon 1 hour of incubation. Both immature and mature DCs internalized NLC to high and comparable levels, and without cytotoxicity. Stimulating DC with TNF-α in the presence of rsv-NLC revealed that, using these

  18. 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

  19. Selective transport of internalized antigens to the cytosol for MHC class I presentation in dendritic cells

    NARCIS (Netherlands)

    Rodriguez, A; Regnault, A; Kleijmeer, M; Ricciardi-Castagnoli, P; Amigorena, S

    1999-01-01

    In order for cytotoxic T cells to initiate immune responses, peptides derived from internalized antigens must be presented to the cytotoxic T cells on major histocompatibility complex (MHC) class I molecules. Here we show that dendritic cells, the only antigen-presenting cells that initiate immune

  20. 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

    Electroporation is well established for transient mRNA transfection of many mammalian cells, including immune cells such as dendritic cells used in cancer immunotherapy. Therapeutic application requires methods to efficiently electroporate and transfect millions of immune cells in a fast process...

  1. 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.

  2. 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.)

  3. Lung Dendritic Cells Facilitate Extrapulmonary Bacterial Dissemination during Pneumococcal Pneumonia

    Directory of Open Access Journals (Sweden)

    Alva eRosendahl

    2013-06-01

    Full Text Available Streptococcus pneumoniae is a leading cause of bacterial pneumonia worldwide. Given the critical role of dendritic cells (DCs in regulating and modulating the immune response to pathogens, we investigated here the role of DCs in S. pneumoniae lung infections. Using a well-established transgenic mouse line which allows the conditional transient depletion of DCs, we showed that ablation of DCs resulted in enhanced resistance to intranasal challenge with S. pneumoniae. DC-depleted mice exhibited delayed bacterial systemic dissemination, significantly reduced bacterial loads in the infected organs and lower levels of serum inflammatory mediators than non-depleted animals. The increased resistance of DC-depleted mice to S. pneumoniae was associated with a better capacity to restrict pneumococci extrapulmonary dissemination. Furthermore, we demonstrated that S. pneumoniae disseminated from the lungs into the regional lymph nodes in a cell-independent manner and that this direct way of dissemination was much more efficient in the presence of DCs. We also provide evidence that S. pneumoniae induces expression and activation of matrix metalloproteinase-9 (MMP-9 in cultured bone marrow-derived DCs. MMP-9 is a protease involved in the breakdown of extracellular matrix proteins and is critical for DC trafficking across extracellular matrix and basement membranes during the migration from the periphery to the lymph nodes. MMP-9 was also significantly up-regulated in the lungs of mice after intranasal infection with S. pneumoniae. Notably, the expression levels of MMP-9 in the infected lungs were significantly decreased after depletion of DCs suggesting the involvement of DCs in MMP-9 production during pneumococcal pneumonia. Thus, we propose that S. pneumoniae can exploit the DC-derived proteolysis to open tissue barriers thereby facilitating its own dissemination from the local site of infection.

  4. Glucocorticoid-Induced Leucine Zipper Protein Controls Macropinocytosis in Dendritic Cells.

    Science.gov (United States)

    Calmette, Joseph; Bertrand, Matthieu; Vétillard, Mathias; Ellouze, Mehdi; Flint, Shaun; Nicolas, Valérie; Biola-Vidamment, Armelle; Pallardy, Marc; Morand, Eric; Bachelerie, Françoise; Godot, Véronique; Schlecht-Louf, Géraldine

    2016-12-01

    Ag sampling is a key process in dendritic cell (DC) biology. DCs use constitutive macropinocytosis, receptor-mediated endocytosis, and phagocytosis to capture exogenous Ags for presentation to T cells. We investigated the mechanisms that regulate Ag uptake by DCs in the steady-state and after a short-term LPS exposure in vitro and in vivo. We show that the glucocorticoid-induced leucine zipper protein (GILZ), already known to regulate effector versus regulatory T cell activation by DCs, selectively limits macropinocytosis, but not receptor-mediated phagocytosis, in immature and recently activated DCs. In vivo, the GILZ-mediated inhibition of Ag uptake is restricted to the CD8α + DC subset, which expresses the highest GILZ level among splenic DC subsets. In recently activated DCs, we further establish that GILZ limits p38 MAPK phosphorylation, providing a possible mechanism for GILZ-mediated macropinocytosis control. Finally, our results demonstrate that the modulation of Ag uptake by GILZ does not result in altered Ag presentation to CD4 T cells but impacts the efficiency of cross-presentation to CD8 T cells. Altogether, our results identify GILZ as an endogenous inhibitor of macropinocytosis in DCs, the action of which contributes to the fine-tuning of Ag cross-presentation. Copyright © 2016 by The American Association of Immunologists, Inc.

  5. Phenotype and polarization of autologous T cells by biomaterial-treated dendritic cells.

    Science.gov (United States)

    Park, Jaehyung; Gerber, Michael H; Babensee, Julia E

    2015-01-01

    Given the central role of dendritic cells (DCs) in directing T-cell phenotypes, the ability of biomaterial-treated DCs to dictate autologous T-cell phenotype was investigated. In this study, we demonstrate that differentially biomaterial-treated DCs differentially directed autologous T-cell phenotype and polarization, depending on the biomaterial used to pretreat the DCs. Immature DCs (iDCs) were derived from human peripheral blood monocytes and treated with biomaterial films of alginate, agarose, chitosan, hyaluronic acid, or 75:25 poly(lactic-co-glycolic acid) (PLGA), followed by co-culture of these biomaterial-treated DCs and autologous T cells. When autologous T cells were co-cultured with DCs treated with biomaterial film/antigen (ovalbumin, OVA) combinations, different biomaterial films induced differential levels of T-cell marker (CD4, CD8, CD25, CD69) expression, as well as differential cytokine profiles [interferon (IFN)-γ, interleukin (IL)-12p70, IL-10, IL-4] in the polarization of T helper (Th) types. Dendritic cells treated with agarose films/OVA induced CD4+CD25+FoxP3+ (T regulatory cells) expression, comparable to untreated iDCs, on autologous T cells in the DC-T co-culture system. Furthermore, in this co-culture, agarose treatment induced release of IL-12p70 and IL-10 at higher levels as compared with DC treatment with other biomaterial films/OVA, suggesting Th1 and Th2 polarization, respectively. Dendritic cells treated with PLGA film/OVA treatment induced release of IFN-γ at higher levels compared with that observed for co-cultures with iDCs or DCs treated with all other biomaterial films. These results indicate that DC treatment with different biomaterial films has potential as a tool for immunomodulation by directing autologous T-cell responses. © 2014 Wiley Periodicals, Inc.

  6. Toll-like receptor expression and function in human dendritic cell subsets: implications for dendritic cell-based anti-cancer immunotherapy.

    NARCIS (Netherlands)

    Schreibelt, G.; Tel, J.; Sliepen, K.H.; Benitez-Ribas, D.; Figdor, C.G.; Adema, G.J.; Vries, I.J.M. de

    2010-01-01

    Dendritic cells (DCs) are central players of the immune response. To date, DC-based immunotherapy is explored worldwide in clinical vaccination trials with cancer patients, predominantly with ex vivo-cultured monocyte-derived DCs (moDCs). However, the extensive culture period and compounds required

  7. Activation of antitumor cytotoxic T lymphocytes by fusions of human dendritic cells and breast carcinoma cells

    Science.gov (United States)

    Gong, Jianlin; Avigan, David; Chen, Dongshu; Wu, Zekui; Koido, Shigeo; Kashiwaba, Masahiro; Kufe, Donald

    2000-03-01

    We have reported that fusions of murine dendritic cells (DCs) and murine carcinoma cells reverse unresponsiveness to tumor-associated antigens and induce the rejection of established metastases. In the present study, fusions were generated with primary human breast carcinoma cells and autologous DCs. Fusion cells coexpressed tumor-associated antigens and DC-derived costimulatory molecules. The fusion cells also retained the functional potency of DCs and stimulated autologous T cell proliferation. Significantly, the results show that autologous T cells are primed by the fusion cells to induce MHC class I-dependent lysis of autologous breast tumor cells. These findings demonstrate that fusions of human breast cancer cells and DCs activate T cell responses against autologous tumors.

  8. Does the exposure to microgravity affect dendritic cell maturation from monocytes?

    Science.gov (United States)

    Monici, Monica; Basile, Venere; Bellik, Lydia; Fusi, Franco; Marziliano, Nicola; Parenti, Astrid; Romano, Giovanni; Conti, Antonio

    2007-09-01

    The exposure to microgravity conditions results in a significant impairment of the immune function. Many reports describe morphological and functional changes in T-lymphocytes, monocytes and neutrophil granulocytes cultured in microgravity, both real and modeled, but very few studies have been made on the effect of microgravity on dendritic cells (DCs) and DC differentiation. DCs are able to process antigens and are the most efficient cells in presenting them to T-lymphocytes, thus giving a crucial contribution to the rise of an effective immune response. The aim of this study was to investigate whether the maturation of DCs from monocytes of astronauts was altered postflight. Blood samples from a crew-member of the Eneide mission were collected before the flight, soon after the return to earth and one year after the mission. In order to generate DCs, monocytes were used as precursors. They were separated, cultured for 6 days in medium supplemented with granulocyte macrophage colony stimulating factor (GM-CSF) and interleukin 4 (IL-4), then furtherly stimulated for 24 hours with a cocktail of cytokines. Differentiation was assessed by flow cytometry and immunofluorescence, assaying the expression of typical DC markers. Gene expression was analysed by RT-PCR. Morphological and functional characteristics were studied by autofluorescence microscopy. The findings showed that the maturation of DCs from monocytes collected from the astronaut immediately postflight was altered. In comparison with controls, significant differences were found in expression of DC markers, expression of genes involved in DC maturation, morphological and functional characteristics.

  9. High salt drives Th17 responses in experimental autoimmune encephalomyelitis without impacting myeloid dendritic cells.

    Science.gov (United States)

    Jörg, Stefanie; Kissel, Jan; Manzel, Arndt; Kleinewietfeld, Markus; Haghikia, Aiden; Gold, Ralf; Müller, Dominik N; Linker, Ralf A

    2016-05-01

    Recently, we have shown that high dietary salt intake aggravates T helper cell (Th) 17 responses and neuroinflammation. Here, we employed in vitro assays for myeloid dendritic cell (mDC) maturation, DC cytokine production, T cell activation and ex vivo analyses in murine experimental autoimmune encephalomyelitis (EAE) to investigate whether the salt effect on Th17 cells is further mediated through DCs in vivo. In cell culture, an excess of 40mM sodium chloride did neither affect the generation, maturation nor the function of DCs, but, in different assays, significantly increased Th17 differentiation. During the initiation phase of MOG35-55 EAE, we did not observe altered DC frequencies or co-stimulatory capacities in lymphoid organs, while IL-17A production and Th17 cells in the spleen were significantly increased. Complementary ex vivo analyses of the spinal cord during the effector phase of EAE showed increased frequencies of Th17 cells, but did not reveal differences in phenotypes of CNS invading DCs. Finally, adaption of transgenic mice harboring a MOG specific T cell receptor to a high-salt diet led to aggravated clinical disease only after active immunization. Wild-type mice adapted to a high-salt diet in the effector phase of EAE, bypassing the priming phase of T cells, only displayed mildly aggravated disease. In summary, our data argue for a direct effect of NaCl on Th17 cells in neuroinflammation rather than an effect primarily exerted via DCs. These data may further fuel our understanding on the dietary impact on different immune cell subsets in autoimmune diseases, such as multiple sclerosis. Copyright © 2016. Published by Elsevier Inc.

  10. 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

  11. 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.

  12. 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. PMID:23977019

  13. 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.

  14. M27 Expressed by Cytomegalovirus Counteracts Effective Type I Interferon Induction of Myeloid Cells but Not of Plasmacytoid Dendritic Cells

    Science.gov (United States)

    Döring, Marius; Lessin, Irina; Frenz, Theresa; Spanier, Julia; Kessler, Annett; Tegtmeyer, Pia; Dağ, Franziska; Thiel, Nadine; Trilling, Mirko; Lienenklaus, Stefan; Weiss, Siegfried; Scheu, Stefanie; Messerle, Martin; Cicin-Sain, Luka; Hengel, Hartmut

    2014-01-01

    ABSTRACT In healthy individuals, the functional immune system effectively confines human cytomegalovirus (CMV) replication, while viral immune evasion and persistence preclude sterile immunity. Mouse CMV (MCMV) is a well-established model to study the delicate CMV-host balance. Effective control of MCMV infection depends on the induction of protective type I interferon (IFN-I) responses. Nevertheless, it is unclear whether in professional antigen-presenting cell subsets MCMV-encoded evasins inhibit the induction of IFN-I responses. Upon MCMV treatment, enhanced expression of MCMV immediate-early and early proteins was detected in bone marrow cultures of macrophages and myeloid dendritic cells compared with plasmacytoid dendritic cell cultures, whereas plasmacytoid dendritic cells mounted more vigorous IFN-I responses. Experiments with Toll-like receptor (TLR)- and/or RIG-I like helicase (RLH)-deficient cell subsets revealed that upon MCMV treatment of myeloid cells, IFN-I responses were triggered independently of TLR and RLH signaling, whereas in plasmacytoid dendritic cells, IFN-I induction was strictly TLR dependent. Macrophages and myeloid dendritic cells treated with either UV-inactivated MCMV or live MCMV that lacked the STAT2 antagonist M27 mounted significantly higher IFN-I responses than cells treated with live wild-type MCMV. In contrast, plasmacytoid dendritic cells responded similarly to UV-inactivated and live MCMV. These experiments illustrated that M27 not only inhibited IFN-I-mediated receptor signaling, but also evaded the induction of IFN responses in myeloid dendritic cells. Furthermore, we found that additional MCMV-encoded evasins were needed to efficiently shut off IFN-I responses of macrophages, but not of myeloid dendritic cells, thus further elucidating the subtle adjustment of the host-pathogen balance. IMPORTANCE MCMV may induce IFN-I responses in fibroblasts and epithelial cells, as well as in antigen-presenting cell subsets. We focused

  15. Butyrate increases IL-23 production by stimulated dendritic cells

    Science.gov (United States)

    Berndt, Bradford E.; Zhang, Min; Owyang, Stephanie Y.; Cole, Tyler S.; Wang, Teresa W.; Luther, Jay; Veniaminova, Natalia A.; Merchant, Juanita L.; Chen, Chun-Chia; Huffnagle, Gary B.

    2012-01-01

    The gut microbiota is essential for the maintenance of intestinal immune homeostasis and is responsible for breaking down dietary fiber into short-chain fatty acids (SCFAs). Butyrate, the most abundant bioactive SCFA in the gut, is a histone deacetylase inhibitor (HDACi), a class of drug that has potent immunomodulatory properties. This characteristic of butyrate, along with our previous discovery that conventional dendritic cells (DCs) are required for the development of experimental colitis, led us to speculate that butyrate may modulate DC function to regulate gut mucosal homeostasis. We found that butyrate, in addition to suppressing LPS-induced bone marrow-derived DC maturation and inhibiting DC IL-12 production, significantly induced IL-23 expression. The upregulation of mRNA subunit IL-23p19 at the pretranslational level was consistent with the role of HDACi on the epigenetic modification of gene expression. Furthermore, the mechanism of IL-23p19 upregulation was independent of Stat3 and ZBP89. Coculture of splenocytes with LPS-stimulated DCs pretreated with or without butyrate was performed and showed a significant induction of IL-17 and IL-10. We demonstrated further the effect of butyrate in vivo using dextran sulfate sodium (DSS)-induced colitis and found that the addition of butyrate in the drinking water of mice worsened DSS-colitis. This is in contrast to the daily intraperitoneal butyrate injection of DSS-treated mice, which mildly improved disease severity. Our study highlights a novel effect of butyrate in upregulating IL-23 production of activated DCs and demonstrates a difference in the host response to the oral vs. systemic route of butyrate administration. PMID:23086919

  16. 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

  17. 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.

  18. The response of monocyte derived dendritic cells following exposure to a nematode larval carbohydrate antigen.

    Science.gov (United States)

    Pernthaner, A; Stasiuk, S J; Roberts, J M; Sutherland, I A

    2012-08-15

    The glycolipid CarLA (carbohydrate larval antigen) is present on the epicuticle of the infective-stage larvae of gastrointestinal nematode parasites infecting livestock. The molecule is lost from the surface of the larvae in the few days post-ingestion by a host animal, and the resulting anti-CarLA antibody response has been demonstrated to be protective in vivo. Both the anti-CarLA response, and anti-parasite immunity in general, are slow to develop, and several months of natural exposure to ingested larvae is required. The current study was designed to provide information on how the anti-CarLA response develops, and focuses on the initial recognition of the molecule by human monocyte derived dendritic cells (mdDC) in vitro. Immunofluorescence and flow cytometry demonstrated that mdDC recognise and internalise both the purified and the native form of CarLA, in the case of the latter once it is shed from the larval surface. However, the recognition of CarLA did not result in classical maturation of DC, while there was only transient or minor up-regulation of CD86, CD83, HLA-DR and CD40. Exposure of mdDC to purified CarLA resulted in the increased production of the pro-inflammatory cytokines IL-6 and to a lesser extent of IL-8 and TNF-α, and a reduced production of the anti-inflammatory cytokine IL-1RA. CarLA therefore has little ability to mature and functionally alter monocyte derived dendritic cell function. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. 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.

  20. Equine infectious anemia virus-infected dendritic cells retain antigen presentation capability.

    Science.gov (United States)

    Rivera, Julie A; McGuire, Travis C

    2005-05-10

    To determine if equine monocyte-derived dendritic cells (DC) were susceptible to equine infectious anemia virus (EIAV) infection, ex vivo-generated DC were infected with virus in vitro. EIAV antigen was detected by immunofluorescence 3 days post-infection with maximum antigen being detected on day 4, whereas there was no antigen detected in DC incubated with the same amount of heat-inactivated EIAV. No cytolytic activity was observed after EIAV(WSU5) infection of DC. These monocyte-derived DC were more effective than macrophages and B cells in stimulating allogenic T lymphocytes. Both infected macrophages and DC stimulated similar levels of memory CTL responses in mixtures of CD8+ and CD4+ cells as detected with (51)Cr-release assays indicating that EIAV infection of DC did not alter antigen presentation. However, EIAV-infected DC were more effective than infected macrophages when used to stimulate memory CTL in isolated CD8+ cells. The maintenance of antigen processing and presenting function by EIAV-infected DC in vitro suggests that this function is maintained during in vivo infection.

  1. Equine infectious anemia virus-infected dendritic cells retain antigen presentation capability

    International Nuclear Information System (INIS)

    Rivera, Julie A.; McGuire, Travis C.

    2005-01-01

    To determine if equine monocyte-derived dendritic cells (DC) were susceptible to equine infectious anemia virus (EIAV) infection, ex vivo-generated DC were infected with virus in vitro. EIAV antigen was detected by immunofluorescence 3 days post-infection with maximum antigen being detected on day 4, whereas there was no antigen detected in DC incubated with the same amount of heat-inactivated EIAV. No cytolytic activity was observed after EIAV WSU5 infection of DC. These monocyte-derived DC were more effective than macrophages and B cells in stimulating allogenic T lymphocytes. Both infected macrophages and DC stimulated similar levels of memory CTL responses in mixtures of CD8+ and CD4+ cells as detected with 51 Cr-release assays indicating that EIAV infection of DC did not alter antigen presentation. However, EIAV-infected DC were more effective than infected macrophages when used to stimulate memory CTL in isolated CD8+ cells. The maintenance of antigen processing and presenting function by EIAV-infected DC in vitro suggests that this function is maintained during in vivo infection

  2. Molecular control of steady-state dendritic cell maturation and immune homeostasis.

    Science.gov (United States)

    Hammer, Gianna Elena; Ma, Averil

    2013-01-01

    Dendritic cells (DCs) are specialized sentinels responsible for coordinating adaptive immunity. This function is dependent upon coupled sensitivity to environmental signs of inflammation and infection to cellular maturation-the programmed alteration of DC phenotype and function to enhance immune cell activation. Although DCs are thus well equipped to respond to pathogens, maturation triggers are not unique to infection. Given that immune cells are exquisitely sensitive to the biological functions of DCs, we now appreciate that multiple layers of suppression are required to restrict the environmental sensitivity, cellular maturation, and even life span of DCs to prevent aberrant immune activation during the steady state. At the same time, steady-state DCs are not quiescent but rather perform key functions that support homeostasis of numerous cell types. Here we review these functions and molecular mechanisms of suppression that control steady-state DC maturation. Corruption of these steady-state operatives has diverse immunological consequences and pinpoints DCs as potent drivers of autoimmune and inflammatory disease.

  3. Molecular Control of Steady-State Dendritic Cell Maturation and Immune Homeostasis

    Science.gov (United States)

    Hammer, Gianna Elena; Ma, Averil

    2014-01-01

    Dendritic cells (DCs) are specialized sentinels responsible for coordinating adaptive immunity. This function is dependent upon coupled sensitivity to environmental signs of inflammation and infection to cellular maturation—the programmed alteration of DC phenotype and function to enhance immune cell activation. Although DCs are thus well equipped to respond to pathogens, maturation triggers are not unique to infection. Given that immune cells are exquisitely sensitive to the biological functions of DCs, we now appreciate that multiple layers of suppression are required to restrict the environmental sensitivity, cellular maturation, and even life span of DCs to prevent aberrant immune activation during the steady state. At the same time, steady-state DCs are not quiescent but rather perform key functions that support homeostasis of numerous cell types. Here we review these functions and molecular mechanisms of suppression that control steady-state DC maturation. Corruption of these steady-state operatives has diverse immunological consequences and pinpoints DCs as potent drivers of autoimmune and inflammatory disease. PMID:23330953

  4. Mast cells and dendritic cells form synapses that facilitate antigen transfer for T cell activation.

    Science.gov (United States)

    Carroll-Portillo, Amanda; Cannon, Judy L; te Riet, Joost; Holmes, Anna; Kawakami, Yuko; Kawakami, Toshiaki; Cambi, Alessandra; Lidke, Diane S

    2015-08-31

    Mast cells (MCs) produce soluble mediators such as histamine and prostaglandins that are known to influence dendritic cell (DC) function by stimulating maturation and antigen processing. Whether direct cell-cell interactions are important in modulating MC/DC function is unclear. In this paper, we show that direct contact between MCs and DCs occurs and plays an important role in modulating the immune response. Activation of MCs through FcεRI cross-linking triggers the formation of stable cell-cell interactions with immature DCs that are reminiscent of the immunological synapse. Direct cellular contact differentially regulates the secreted cytokine profile, indicating that MC modulation of DC populations is influenced by the nature of their interaction. Synapse formation requires integrin engagement and facilitates the transfer of internalized MC-specific antigen from MCs to DCs. The transferred material is ultimately processed and presented by DCs and can activate T cells. The physiological outcomes of the MC-DC synapse suggest a new role for intercellular crosstalk in defining the immune response. © 2015 Carroll-Portillo et al.

  5. Magnetic resonance tracking of dendritic cells in melanoma patients for monitoring of cellular therapy

    NARCIS (Netherlands)

    de Vries, I. Jolanda M.; Lesterhuis, W. Joost; Barentsz, Jelle O.; Verdijk, Pauline; van Krieken, J. Han; Boerman, Otto C.; Oyen, Wim J. G.; Bonenkamp, Johannes J.; Boezeman, Jan B.; Adema, Gosse J.; Bulte, Jeff W. M.; Scheenen, Tom W. J.; Punt, Cornelis J. A.; Heerschap, Arend; Figdor, Carl G.

    2005-01-01

    The success of cellular therapies will depend in part on accurate delivery of cells to target organs. In dendritic cell therapy, in particular, delivery and subsequent migration of cells to regional lymph nodes is essential for effective stimulation of the immune system. We show here that in vivo

  6. Magnetic resonance tracking of dendritic cells in melanoma patients for monitoring of cellular therapy.

    NARCIS (Netherlands)

    Vries, I.J.M. de; Lesterhuis, W.J.; Barentsz, J.O.; Verdijk, P.; Krieken, J.H.J.M. van; Boerman, O.C.; Oyen, W.J.G.; Bonenkamp, J.J.; Boezeman, J.B.M.; Adema, G.J.; Bulte, J.W.; Scheenen, T.W.J.; Punt, C.J.A.; Heerschap, A.; Figdor, C.G.

    2005-01-01

    The success of cellular therapies will depend in part on accurate delivery of cells to target organs. In dendritic cell therapy, in particular, delivery and subsequent migration of cells to regional lymph nodes is essential for effective stimulation of the immune system. We show here that in vivo

  7. 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

  8. Regulation of the multifaceted functions of human plasmacytoid dendritic cells: a polyphonic policy

    NARCIS (Netherlands)

    Jachimowski, L.C.M.

    2015-01-01

    Plasmacytoid dendritic cells (pDCs) are immune cells that belong to the innate immune system. Since pDCs are able to directly respond towards a broad range of viruses and bacteria and are capable of presenting antigens to T cells, pDCs have been put forward as a link between the innate and adaptive

  9. 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.

  10. Modulation of synaptic potentials and cell excitability by dendritic ...

    Indian Academy of Sciences (India)

    The nucleus accumbens (NAc), a critical structure of the brain reward circuit, is implicated in normal goal-directed behaviour and learning as well as pathological conditions like schizophrenia and addiction. Its major cellular substrates, the medium spiny (MS) neurons, possess a wide variety of dendritic active conductances ...

  11. 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.

  12. 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

  13. Impaired IFN-α-mediated signal in dendritic cells differentiates active from latent tuberculosis.

    Directory of Open Access Journals (Sweden)

    Stefania Parlato

    Full Text Available Individuals exposed to Mycobacterium tuberculosis (Mtb may be infected and remain for the entire life in this condition defined as latent tuberculosis infection (LTBI or develop active tuberculosis (TB. Among the multiple factors governing the outcome of the infection, dendritic cells (DCs play a major role in dictating antibacterial immunity. However, current knowledge on the role of the diverse components of human DCs in shaping specific T-cell response during Mtb infection is limited. In this study, we performed a comparative evaluation of peripheral blood circulating DC subsets as well as of monocyte-derived Interferon-α DCs (IFN-DCs from patients with active TB, subjects with LTBI and healthy donors (HD. The proportion of circulating myeloid BDCA3+ DCs (mDC2 and plasmacytoid CD123+ DCs (pDCs declined significantly in active TB patients compared to HD, whereas the same subsets displayed a remarkable activation in LTBI subjects. Simultaneously, the differentiation of IFN-DCs from active TB patients resulted profoundly impaired compared to those from LTBI and HD individuals. Importantly, the altered developmental trait of IFN-DCs from active TB patients was associated with down-modulation of IFN-linked genes, marked changes in molecular signaling conveying antigen (Ag presentation and full inability to induce Ag-specific T cell response. Thus, these data reveal an important role of IFN-α in determining the induction of Mtb-specific immunity.

  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. CD8+ T cells Sabotage their own Memory Potential through IFN-γ-dependent modification of the IL-12/IL-15Rα axis on Dendritic Cells

    Science.gov (United States)

    Kohlhapp, Frederick J.; Zloza, Andrew; O’Sullivan, Jeremy A.; Moore, Tamson V.; Lacek, Andrew T.; Jagoda, Michael C.; McCracken, James; Cole, David J.; Guevara-Patiño, José A.

    2012-01-01

    CD8+ T cell responses have been shown to be regulated by dendritic cells (DCs) and CD4+ T cells leading to the tenet that CD8+ T cells play a passive role in their own differentiation. In contrast, by using a DNA vaccination model, to separate the events of vaccination from those of CD8+ T cell priming, we demonstrate that CD8+ T cells, themselves, actively limit their own memory potential through CD8+ T cell-derived IFN-γ-dependent modification of the IL-12/IL-15Rα axis on DCs. Such CD8+ T cell-driven cytokine alterations result in increased T-bet and decreased Bcl-2 expression, and thus decreased memory progenitor formation. These results identify an unrecognized role for CD8+ T cells in the regulation of their own effector differentiation fate and a previously uncharacterized relationship between the balance of inflammation and memory formation. PMID:22430740

  16. Unsupervised High-Dimensional Analysis Aligns Dendritic Cells across Tissues and Species

    NARCIS (Netherlands)

    M. Guilliams (Martin); Dutertre, C.-A. (Charles-Antoine); C.L. Scott (C.); N. McGovern (Naomi); D. Sichien (Dorine); Chakarov, S. (Svetoslav); Van Gassen, S. (Sofie); Chen, J. (Jinmiao); M. Poidinger (Michael); S. de Prijck (Sofie); S.J. Tavernier (Simon); Low, I. (Ivy); Irac, S.E. (Sergio Erdal); Mattar, C.N. (Citra Nurfarah); Sumatoh, H.R. (Hermi Rizal); Low, G.H.L. (Gillian Hui Ling); Chung, T.J.K. (Tam John Kit); Chan, D.K.H. (Dedrick Kok Hong); Tan, K.K. (Ker Kan); Hon, T.L.K. (Tony Lim Kiat); Fossum, E. (Even); Bogen, B. (Bjarne); Choolani, M. (Mahesh); Chan, J.K.Y. (Jerry Kok Yen); A. Larbi (Anis); H. Luche (Hervé); S. Henri (Sandrine); Y. Saeys (Yvan); Newell, E.W. (Evan William); B.N.M. Lambrecht (Bart); B. Malissen (Bernard); F. Ginhoux (Florent)

    2016-01-01

    textabstractDendritic cells (DCs) are professional antigen-presenting cells that hold great therapeutic potential. Multiple DC subsets have been described, and it remains challenging to align them across tissues and species to analyze their function in the absence of macrophage contamination. Here,

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

    Indian Academy of Sciences (India)

    2015-02-04

    Feb 4, 2015 ... After centrifugation (500g) for. 20 min, the cells collected from the interface were cultured ..... pathway. Blood 92 745–755. Seth S, Oberdörfer L, Hyde R, Hoff K, Thies V, Worbs T, Schmitz S and Förster R 2011 CCR7 essentially contributes to the homing of plasmacytoid dendritic cells to lymph nodes under ...

  18. 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

    Dendritic cells (DC) modulated to induce T cell hyporesponsiveness have promising potential in immunotherapy of autoimmune disorders and for the prevention of allograft rejection. While studying the effect of immunosuppressive agents on the maturation of DC we found that 1alpha,25-Dihydroxyvitamin...

  19. Differential regulation of C-type lectin expression on tolerogenic dendritic cell subsets

    NARCIS (Netherlands)

    van Vliet, Sandra J.; van Liempt, Ellis; Geijtenbeek, Teunis B. H.; van Kooyk, Yvette

    2006-01-01

    Antigen presenting cells (APC) express high levels of C-type lectins, which play a major role in cellular interactions as well as pathogen recognition and antigen presentation. The C-type lectin macrophage galactose-type lectin (MGL), expressed by dendritic cells (DC) and macrophages, mediates

  20. Enumeration and phenotypical analysis of distinct dendritic cell subsets in psoriatic arthritis and rheumatoid arthritis

    NARCIS (Netherlands)

    Jongbloed, Sarah L.; Lebre, M. Cristina; Fraser, Alasdair R.; Gracie, J. Alastair; Sturrock, Roger D.; Tak, Paul P.; McInnes, Iain B.

    2006-01-01

    Dendritic cells (DCs) comprise heterogeneous subsets of professional antigen-presenting cells, linking innate and adaptive immunity. Analysis of DC subsets has been hampered by a lack of specific DC markers and reliable quantitation assays. We characterised the immunophenotype and functional

  1. Dendritic cell vaccination in melanoma patients: From promising results to future perspectives

    NARCIS (Netherlands)

    Boudewijns, S; Bloemendal, M.; Gerritsen, W.R.; Vries, I.J.M. de; Schreibelt, G.

    2016-01-01

    Dendritic cells (DCs) play an important role in the induction of antitumor immunity. Therefore, they are used as anti-cancer vaccines in clinical studies in various types of cancer. DC vaccines are generally well tolerated and able to induce antigen-specific T cell responses in melanoma patients.

  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. Phenotypic and functional characterization of mature dendritic cells from pediatric cancer patients.

    NARCIS (Netherlands)

    Jacobs, J.F.M.; Hoogerbrugge, P.M.; Rakt, M.W.M.M. van de; Aarntzen, E.H.J.G.; Figdor, C.G.; Adema, G.J.; Vries, I.J.M. de

    2007-01-01

    BACKGROUND: Dendritic cells (DCs) are the most potent antigen-presenting cells of the immune system. Clinical trials have demonstrated that mature DCs loaded with tumor-associated antigens can induce tumor-specific immune responses. Theoretically, pediatric patients are excellent candidates for

  4. Dendritic cells inversely regulate airway inflammation in cigarette smoke-exposed mice

    NARCIS (Netherlands)

    Ezzati Givi, Masoumeh; Akbari, Peyman; Boon, Louis; Puzovic, Vladimir S; Bezemer, Gillina F G; Ricciardolo, Fabio L M; Folkerts, Gert; Redegeld, Frank A; Mortaz, Esmaeil

    The recruitment and activation of inflammatory cells into the respiratory system is considered a crucial feature in the pathophysiology of chronic obstructive pulmonary disease (COPD). Since dendritic cells (DCs) have a pivotal role in the onset and regulation of immune responses, we investigated

  5. In situ tumor destruction: towards in vivo modulation of immune responses by dendritic cells.

    NARCIS (Netherlands)

    Brok, M.H.M.G.M. den

    2006-01-01

    Dendritic cells (DC's) are professional antigen presenting cells that play a critical role in initiation of immune responses. In recent years, it has become evident that tumor antigens presented by ex vivo generated DC can evoke tumor-specific responses in cancer patients. Although promising results

  6. Suppression of Th1-mediated autoimmunity by embryonic stem cell-derived dendritic cells.

    Directory of Open Access Journals (Sweden)

    Tokunori Ikeda

    Full Text Available We herein demonstrate the immune-regulatory effect of embryonic stem cell-derived dendritic cells (ES-DCs using two models of autoimmune disease, namely non-obese diabetic (NOD mice and experimental autoimmune encephalomyelitis (EAE. Treatment of pre-diabetic NOD mice with ES-DCs exerted almost complete suppression of diabetes development during the observation period for more than 40 weeks. The prevention of diabetes by ES-DCs was accompanied with significant reduction of insulitis and decreased number of Th1 and Th17 cells in the spleen. Development of EAE was also inhibited by the treatment with ES-DCs, and the therapeutic effect was obtained even if ES-DCs were administrated after the onset of clinical symptoms. Treatment of EAE-induced mice with ES-DCs reduced the infiltration of inflammatory cells into the spinal cord and suppressed the T cell response to the myelin antigen. Importantly, the ES-DC treatment did not affect T cell response to an exogenous antigen. As the mechanisms underlying the reduction of the number of infiltrating Th1 cells, we observed the inhibition of differentiation and proliferation of Th1 cells by ES-DCs. Furthermore, the expression of VLA-4α on Th1 cells was significantly inhibited by ES-DCs. Considering the recent advances in human induced pluripotent stem cell-related technologies, these results suggest a clinical application for pluripotent stem cell-derived dendritic cells as a therapy for T cell-mediated autoimmune diseases.

  7. 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.

  8. The low efficiency of dendritic cells and macrophages from mice susceptible to Paracoccidioides brasiliensis in inducing a Th1 response

    Directory of Open Access Journals (Sweden)

    S.R. Almeida

    2001-04-01

    Full Text Available In the present study we evaluated T cell proliferation and Th lymphokine patterns in response to gp43 from Paracoccidioides brasiliensis presented by isolated dendritic cells from susceptible and resistant mice. T cell proliferation assays showed that dendritic cells from susceptible mice were less efficient than those from resistant mice. The pattern of T cell lymphokines stimulated by dendritic cells was always Th1, although the levels of IL-2 and IFN-gamma were lower in T cell cultures from susceptible mice. To determie whether different antigen-presenting cells such as macrophages and dendritic cells stimulated different concentrations of Th1 lymphokines, the production of IFN-gamma and IL-2 was measured. It was observed that dendritic cells were more efficient than macrophages in stimulating lymphoproliferation in resistant mice. However, no significant difference was observed for IFN-gamma or IL-2 production. When cells from susceptible mice were used, macrophages were more efficient in stimulating lymphoproliferation than dendritic cells, but no difference was observed in the production of Th1 cytokine. Taken together, these results suggest the lower efficiency of dendritic cells and macrophages from B10.A mice in stimulating T cells that secrete Th1 lymphokines in vitro, an effect that may be involved in the progression of the disease in vivo.

  9. Generation of dendritic cells for immunotherapy is minimally impaired by granulocytes in the monocyte preparation.

    Science.gov (United States)

    ten Brinke, Anja; Karsten, Miriam L; Dieker, Miranda C; Zwaginga, Jaap Jan; Vrielink, Hans; Marieke van Ham, S

    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 cost-effective way to isolate monocytes directly from leukapheresis material in a closed system is by elutriation with the Elutra cell separation system. In the Elutra, granulocytes co-purify with the monocytes. Therefore, we studied if and to what extent the presence of granulocytes in a monocyte product affects the generation of mature DCs. The presence of up to 16% granulocytes in the monocyte product had no significant effects on the quality of the DCs formed. The presence of higher granulocyte percentages, however, gradually altered DC quality. In this respect, the presence of higher number of granulocytes induced significant lower migratory capacity of the DCs and lower expression levels of CD80, CD40 and CD86. No effects were observed on the DC yield, cytokine production or the stimulatory capacity of the DCs in MLR. In conclusion, the presence of 20-30% granulocytes in a monocyte product has no major influence on the quality of the DCs generated from monocytes. Therefore, the Elutra is a suitable closed system apparatus to separate monocytes from other blood components for the generation of DCs, even from leukapheresis material which contains a high number of granulocytes.

  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. Mechanical removal of dendritic cell-generating non-classical monocytes via ex vivo lung perfusion.

    Science.gov (United States)

    Stone, John P; Sevenoaks, Hannah; Sjöberg, Trygve; Steen, Stig; Yonan, Nizar; Fildes, James E

    2014-08-01

    Ex vivo lung perfusion (EVLP) is a novel procedure designed to rapidly assess and recondition unusable donor lungs for transplantation (LTx). EVLP may reduce graft immunogenicity and allorecognition via removal of passenger leukocytes. We aimed to explore this hypothesis using human EVLP and in vitro analysis. Explanted human lungs (n = 7) underwent standard EVLP. Perfusate samples and the leukocyte filter were collected, and cells characterized via flow cytometry. Isolated alveolar monocytes (from post-LTx bronchoalveolar lavage) were differentiated to dendritic cells and characterized (n = 10). An in vitro (air epithelial-liquid endothelial) lung model was utilized to evaluate monocyte migration and differentiation within the lung. Non-classical monocytes (NCM, normally <1% of total white blood cell repertoire) mobilized within 30 minutes of EVLP and represented 80.04% of the passenger leukocyte population. This subset readily differentiated to dendritic cells and secreted pro-inflammatory cytokines (interferon-γ and interleukin-2) after stimulation. NCM rapidly diapedesed from the vascular bed to the alveolus and, when cultured on the alveolus, differentiated to dendritic cells with inflammatory phenotypes. The lung possesses a reservoir of NCM, which can readily diapedese to the alveolus or mobilize in the circulation. After activation, NCM differentiate to inflammatory dendritic cells with T-cell co-stimulatory capacity. EVLP may impart additional benefits after LTx via the removal of passenger monocytes, which may represent a previously unidentified beneficial mechanism of action. Copyright © 2014 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

  12. Induction of complete and molecular remissions in acute myeloid leukemia by Wilms' tumor 1 antigen-targeted dendritic cell vaccination.

    NARCIS (Netherlands)

    Tendeloo, V.F. Van; Velde, A. van de; Driessche, A. Van; Cools, N.; Anguille, S.; Ladell, K.; Gostick, E.; Vermeulen, K.; Pieters, K.; Nijs, G.; Stein, B.; Smits, E.L.; Schroyens, W.A.; Gadisseur, A.P.; Vrelust, I.; Jorens, P.G.; Goossens, H.; Vries, I.J.M. de; Price, D.A.; Oji, Y.; Oka, Y.; Sugiyama, H.; Berneman, Z.N.

    2010-01-01

    Active immunization using tumor antigen-loaded dendritic cells holds promise for the adjuvant treatment of cancer to eradicate or control residual disease, but so far, most dendritic cell trials have been performed in end-stage cancer patients with high tumor loads. Here, in a phase I/II trial, we

  13. Three-day dendritic cells for vaccine development: Antigen uptake, processing and presentation

    Directory of Open Access Journals (Sweden)

    Schendel Dolores J

    2010-09-01

    Full Text Available Abstract Background Antigen-loaded dendritic cells (DC are capable of priming naïve T cells and therefore represent an attractive adjuvant for vaccine development in anti-tumor immunotherapy. Numerous protocols have been described to date using different maturation cocktails and time periods for the induction of mature DC (mDC in vitro. For clinical application, the use of mDC that can be generated in only three days saves on the costs of cytokines needed for large scale vaccine cell production and provides a method to produce cells within a standard work-week schedule in a GMP facility. Methods In this study, we addressed the properties of antigen uptake, processing and presentation by monocyte-derived DC prepared in three days (3d mDC compared with conventional DC prepared in seven days (7d mDC, which represent the most common form of DC used for vaccines to date. Results Although they showed a reduced capacity for spontaneous antigen uptake, 3d mDC displayed higher capacity for stimulation of T cells after loading with an extended synthetic peptide that requires processing for MHC binding, indicating they were more efficient at antigen processing than 7d DC. We found, however, that 3d DC were less efficient at expressing protein after introduction of in vitro transcribed (ivtRNA by electroporation, based on published procedures. This deficit was overcome by altering electroporation parameters, which led to improved protein expression and capacity for T cell stimulation using low amounts of ivtRNA. Conclusions This new procedure allows 3d mDC to replace 7d mDC for use in DC-based vaccines that utilize long peptides, proteins or ivtRNA as sources of specific antigen.

  14. Aryl Hydrocarbon Receptor Activation Reduces Dendritic Cell Function during Influenza Virus Infection

    Science.gov (United States)

    Jin, Guang-Bi; Moore, Amanda J.; Head, Jennifer L.; Neumiller, Joshua J.; Lawrence, B. Paige

    2010-01-01

    It has long been known that activation of the aryl hydrocarbon receptor (AhR) by ligands such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) suppresses T cell–dependent immune responses; however, the underlying cellular targets and mechanism remain unclear. We have previously shown that AhR activation by TCDD reduces the proliferation and differentiation of influenza virus–specific CD8+ T cells through an indirect mechanism; suggesting that accessory cells are critical AhR targets during infection. Respiratory dendritic cells (DCs) capture antigen, migrate to lymph nodes, and play a key role in activating naive CD8+ T cells during respiratory virus infection. Herein, we report an examination of how AhR activation alters DCs in the lung and affects their trafficking to and function in the mediastinal lymph nodes (MLN) during infection with influenza virus. We show that AhR activation impairs lung DC migration and reduces the ability of DCs isolated from the MLN to activate naive CD8+ T cells. Using novel AhR mutant mice, in which the AhR protein lacks its DNA-binding domain, we show that the suppressive effects of TCDD require that the activated AhR complex binds to DNA. These new findings suggest that AhR activation by chemicals from our environment impacts DC function to stimulate naive CD8+ T cells and that immunoregulatory genes within DCs are critical targets of AhR. Moreover, our results reinforce the idea that environmental signals and AhR ligands may contribute to differential susceptibilities and responses to respiratory infection. PMID:20498003

  15. Tumours of histiocytes and accessory dendritic cells : an immunohistochemical approach to classification from the International Lymphoma Study Group based on 61 cases

    NARCIS (Netherlands)

    Pileri, SA; Grogan, TM; Harris, NL; Banks, P; Campo, E; Chan, JKC; Favera, RD; Delsol, G; De Wolf-Peeters, C; Falini, B; Gascoyne, RD; Gaulard, P; Gatter, KC; Isaacson, PG; Jaffe, ES; Kluin, P; Knowles, DM; Mason, DY; Mori, S; Muller-Hermelink, HK; Piris, MA; Ralfkiaer, E; Stein, H; Su, IJ; Warnke, RA; Weiss, LM

    Neoplasms of histiocytes and dendritic cells are rare, and their phenotypic and biological definition is incomplete. Seeking to identify antigens detectable in paraffin-embedded sections that might allow a more complete, rational immunophenotypic classification of histiocytic/dendritic cell

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

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    Simone König

    Full Text Available 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.

  17. The cell biology of cross-presentation and the role of dendritic cell subsets.

    Science.gov (United States)

    Lin, Ming-Lee; Zhan, Yifan; Villadangos, Jose A; Lew, Andrew M

    2008-01-01

    The cell biology of cross-presentation is reviewed regarding exogenous antigen uptake, antigen degradation and entry into the major histocompatibility complex class I pathway. Whereas cross-presentation is not associated with enhanced phagocytic ability, certain receptors may favour uptake for cross-presentation for example mannose receptor for soluble glycoproteins. Perhaps, the defining property of the cross-presenting cell is some specialization in host machinery for handling and transport of antigen across organelles. Both cytosolic and vacuolar pathways are discussed. Which dendritic cell (DC) subset is the cross-presenting cell is explored. Cross-presentation is found within the CD8(+) subset resident in lymphoid organs. The role of other DC subsets (especially the migratory CD8(-) DC) and the route of antigen delivery are also discussed. Further consideration is given to antigen transfer between DC subsets and differential presentation to naive vs memory T cells.

  18. Dendritic cells as Achilles? heel and Trojan horse during varicella zoster virus infection

    OpenAIRE

    Sch?nrich, G?nther; Raftery, Martin J.

    2015-01-01

    Varicella zoster virus (VZV), a human alphaherpesvirus, causes varicella and subsequently establishes latency within sensory nerve ganglia. Later in life VZV can reactivate to cause herpes zoster. A reduced frequency of VZV-specific T cells is strongly associated with herpes zoster illustrating that these immune cells are central to control latency. Dendritic cells (DCs) are required for the generation of VZV-specific T cells. However, DCs can also be infected in vitro and in vivo allowing VZ...

  19. Dendritic cells as Achilles' heel and Trojan horse during varicella zoster virus infection

    OpenAIRE

    Günther eSchönrich; Martin J. Raftery

    2015-01-01

    Varicella zoster virus (VZV), a human alphaherpesvirus, causes varicella and subsequently estab-lishes latency within sensory nerve ganglia. Later in life VZV can reactivate to cause herpes zoster. A reduced frequency of VZV-specific T cells is strongly associated with herpes zoster illustrating that these immune cells are central to control latency. Dendritic cells (DCs) are required for the generation of VZV-specific T cells. However, DCs can also be infected in vitro and in vivo allowing V...

  20. Butyrate and retinoic acid imprint mucosal-like dendritic cell development synergistically from bone marrow cells.

    Science.gov (United States)

    Qiang, Y; Xu, J; Yan, C; Jin, H; Xiao, T; Yan, N; Zhou, L; An, H; Zhou, X; Shao, Q; Xia, S

    2017-09-01

    Accumulating data show that the phenotypes and functions of distinctive mucosal dendritic cells (DCs) in the gut are regulated by retinoic acid (RA). Unfortunately, the exact role of butyrate in RA-mediated mucosal DC differentiation has not been elucidated thoroughly to date. Mucosal-like dendritic cell differentiation was completed in vitro by culturing bone marrow cells with growth factors [granulocyte-macrophage colony-stimulating factor (GM-CSF/interleukin (IL)-4], RA and/or butyrate. The phenotypes, cytokine secretion, immune functions and levels of retinal dehydrogenase of different DCs were detected using quantitative polymerase chain reaction (qPCR), enzyme-linked immunosorbent assay (ELISA) and flow cytometry, respectively. The results showed that RA-induced DCs (RA-DCs) showed mucosal DC properties, including expression of CD103 and gut homing receptor α 4 β 7 , low proinflammatory cytokine secretion and low priming capability to antigen-specific CD4 + T cells. Butyrate-treated RA-DCs (Bu-RA-DCs) decreased CD11c, but increased CD103 and α 4 β 7 expression. Moreover, the CD4 + T priming capability and the levels of retinal dehydrogenase of RA-DCs were suppressed significantly by butyrate. Thus, butyrate and retinoic acid have different but synergistic regulatory functions on mucosal DC differentiation, indicating that immune homeostasis in the gut depends largely upon RA and butyrate to imprint different mucosal DC subsets, both individually and collectively. © 2017 British Society for Immunology.

  1. Stressful Presentations: Mild Chronic Cold Stress in Mice Influences Baseline Properties of Dendritic Cells

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    Kathleen Marie Kokolus

    2014-02-01

    Full Text Available The ability of dendritic cells to stimulate and regulate T cells is critical to effective anti-tumor immunity. Therefore, it is important to fully recognize any inherent factors which may influence DC function under experimental conditions, especially in laboratory mice since they are used so heavily to study immune responses. Physiological stress is well recognized to impair several arms of immune protection. The goals of this report are to briefly summarize previous work revealing how DCs respond to various forms of physiologically relevant stress and to present new data highlighting the potential for chronic mild cold stress inherent in mice housed at standard ambient temperatures required for laboratory mice to influence baseline DCs properties. Since recent data from our group shows that CD8+ T cell function is altered by mild chronic cold stress and since DC function is crucial for CD8+ T cell activation, we wondered whether mild cold stress may also be influencing DC properties. We found increased numbers of splenic DCs (CD11c+ in cold stressed mice compared to mice housed at a thermoneutral temperature, which significantly reduces cold stress. However, many of the DCs which are expanded in cold stressed mice express an immature phenotype. We also found that antigen presentation and ability of splenocytes to activate T cells were impaired compared to that seen in DCs isolated from mice at thermoneutrality. The new data presented here strongly suggest that the housing temperature of mice can affect fundamental properties of DC function which in turn could be influencing the response of DCs to added experimental stressors or other treatments.

  2. Neuroantigen-specific autoregulatory CD8+ T cells inhibit autoimmune demyelination through modulation of dendritic cell function.

    Directory of Open Access Journals (Sweden)

    Venkatesh P Kashi

    Full Text Available Experimental autoimmune encephalomyelitis (EAE is a well-established murine model of multiple sclerosis, an immune-mediated demyelinating disorder of the central nervous system (CNS. We have previously shown that CNS-specific CD8+ T cells (CNS-CD8+ ameliorate EAE, at least in part through modulation of CNS-specific CD4+ T cell responses. In this study, we show that CNS-CD8+ also modulate the function of CD11c+ dendritic cells (DC, but not other APCs such as CD11b+ monocytes or B220+ B cells. DC from mice receiving either myelin oligodendrocyte glycoprotein-specific CD8+ (MOG-CD8+ or proteolipid protein-specific CD8+ (PLP-CD8+ T cells were rendered inefficient in priming T cell responses from naïve CD4+ T cells (OT-II or supporting recall responses from CNS-specific CD4+ T cells. CNS-CD8+ did not alter DC subset distribution or MHC class II and CD86 expression, suggesting that DC maturation was not affected. However, the cytokine profile of DC from CNS-CD8+ recipients showed lower IL-12 and higher IL-10 production. These functions were not modulated in the absence of immunization with CD8-cognate antigen, suggesting an antigen-specific mechanism likely requiring CNS-CD8-DC interaction. Interestingly, blockade of IL-10 in vitro rescued CD4+ proliferation and in vivo expression of IL-10 was necessary for the suppression of EAE by MOG-CD8+. These studies demonstrate a complex interplay between CNS-specific CD8+ T cells, DC and pathogenic CD4+ T cells, with important implications for therapeutic interventions in this disease.

  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. Polymeric inserts differing in their chemical composition as substrates for dendritic cell cultivation.

    Science.gov (United States)

    Roch, Toralf; Kratz, Karl; Ma, Nan; Lendlein, Andreas

    2015-01-01

    Dendritic cells (DC) contribute to immunity by presenting antigens to T cells and shape the immune response by the secretion of cytokines. Due to their immune stimulatory potential DC-based therapies are promising approaches to overcome tolerance e.g. against tumors. In order to enforce the immunogenicity of DCs, they have to be matured and activated in vitro, which requires an appropriate cell culture substrate, supporting their survival expansion and activation.Since most cell culture devices are not optimized for DC growth, it is hypothesized that polymers with certain physicochemical properties can positively influence the DC cultures. With the aim to evaluate the effects that polymers with different chemical compositions have on the survival, the activation status, and the cytokine/chemokine secretion profile of DC, their interaction with polystyrene (PS), polycarbonate (PC), poly(ether imide) (PEI), and poly(styrene-co-acrylonitrile) (PSAN)-based cell culture inserts was investigated. By using this insert system, which fits exactly into 24 well cell culture plates, effects induced from the culture dish material can be excluded. The viability of untreated DC after incubation with the different inserts was not influenced by the different inserts, whereas LPS-activated DC showed an increased survival after cultivation on PC, PS, and PSAN compared to tissue culture polystyrene (TCP). The activation status of DC estimated by the expression of CD40, CD80, CD83, CD86 and HLA-DR expression was not altered by the different inserts in untreated DC but slightly reduced when LPS-activated DC were cultivated on PC, PS, PSAN, and PEI compared to TCP. For each polymeric cell culture insert a distinct cytokine profile could be observed.Since inserts with different chemical compositions of the inserts did not substantially alter the behavior of DC all insert systems could be considered as alternative substrate. The observed increased survival on some polymers, which showed in

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

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    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.

  6. MHC II in Dendritic Cells is Targeted to Lysosomes or T Cell-Induced Exosomes Via Distinct Multivesicular Body Pathways

    NARCIS (Netherlands)

    Buschow, Sonja I.; Nolte-'t Hoen, Esther N. M.; van Niel, Guillaume; Pols, Maaike S.; ten Broeke, Toine; Lauwen, Marjolein; Ossendorp, Ferry; Melief, Cornelis J. M.; Raposo, Graca; Wubbolts, Richard; Wauben, Marca H. M.; Stoorvogel, Willem

    2009-01-01

    Dendritic cells (DCs) express major histocompatibility complex class II (MHC II) to present peptide antigens to T cells. In immature DCs, which bear low cell surface levels of MHC II, peptide-loaded MHC II is ubiquitinated. Ubiquitination drives the endocytosis and sorting of MHC II to the luminal

  7. Combining autologous dendritic cell therapy with CD3 antibodies promotes regulatory T cells and permanent islet allograft acceptance

    NARCIS (Netherlands)

    Baas, M.C.; Kuhn, C.; Valette, F.; Mangez, C.; Duarte, M.S.; Hill, M.; Besancon, A.; Chatenoud, L.; Cuturi, M.C.; You, S.

    2014-01-01

    Cell therapy and the use of mAbs that interfere with T cell effector functions constitute promising approaches for the control of allograft rejection. In the current study, we investigated a novel approach combining administration of autologous tolerogenic dendritic cells with short-term treatment

  8. 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.

  9. Characterization of dendritic cells and macrophages generated by directed differentiation from mouse induced pluripotent stem cells.

    Science.gov (United States)

    Senju, Satoru; Haruta, Miwa; Matsunaga, Yusuke; Fukushima, Satoshi; Ikeda, Tokunori; Takahashi, Kazutoshi; Okita, Keisuke; Yamanaka, Shinya; Nishimura, Yasuharu

    2009-05-01

    Methods have been established to generate dendritic cells (DCs) from mouse and human embryonic stem (ES) cells. We designated them as ES-DCs and mouse models have demonstrated the induction of anti-cancer immunity and prevention of autoimmune disease by in vivo administration of genetically engineered ES-DCs. For the future clinical application of ES-DCs, the histoincompatibility between patients to be treated and available human ES cells and the ethical concerns associated with human ES cells may be serious obstacles. However, recently developed induced pluripotent stem (iPS) cell technology is expected to resolve these issues. This report describes the generation and characterization of DCs derived from mouse iPS cells. The iPS cell-derived DCs (iPS-DCs) possessed the characteristics of DCs including the capacity of T-cell-stimulation, antigen-processing and presentation and cytokine production. DNA microarray analyses revealed the upregulation of genes related to antigen-presenting functions during differentiation into iPS-DCs and similarity in gene expression profile in iPS-DCs and bone marrow cell-derived DCs. Genetically modified iPS-DCs expressing antigenic protein primed T-cells specific to the antigen in vivo and elicited efficient antigen-specific anti-tumor immunity. In addition, macrophages were generated from iPS cells (iPS-MP). iPS-MP were comparable with bone marrow cell-derived macrophages in the cell surface phenotype, functions, and gene expression profiles.

  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

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    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. Long-term depression of climbing fiber-evoked calcium transients in Purkinje cell dendrites

    Science.gov (United States)

    Weber, John T.; De Zeeuw, Chris I.; Linden, David J.; Hansel, Christian

    2003-01-01

    In recent years much has been learned about the molecular requirements for inducing long-term synaptic depression (LTD) in various brain regions. However, very little is known about the consequences of LTD induction for subsequent signaling events in postsynaptic neurons. We have addressed this issue by examining homosynaptic LTD at the cerebellar climbing fiber (CF)–Purkinje cell (PC) synapse. This synapse is built for reliable and massive excitation: Activation of a single axon produces an unusually large α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor-mediated synaptic current, the depolarization of which drives a regenerative complex spike producing a large, widespread Ca2+ transient in PC dendrites. Here we test whether CF LTD has an impact on dendritic, complex spike-evoked Ca2+ signals by simultaneously performing long-term recordings of complex spikes and microfluorimetric Ca2+ measurements in PC dendrites in rat cerebellar slices. Our data show that LTD of the CF excitatory postsynaptic current produces a reduction in both slow components of the complex spike waveform and complex spike-evoked dendritic Ca2+ transients. This LTD of dendritic Ca2+ signals may provide a neuroprotective mechanism and/or constitute “heterosynaptic metaplasticity” by reducing the probability for subsequent induction of those forms of use-dependent plasticity, which require CF-evoked Ca2+ signals such as parallel fiber–PC LTD and interneuron–PC LTP. PMID:12601151

  13. Alterations in apical dendrite bundling in the somatosensory cortex of 5-HT3A receptor knockout mice.

    NARCIS (Netherlands)

    Smit-Rigter, L.A.; Wadman, W.J.; van Hooft, J.A.

    2011-01-01

    In various species and areas of the cerebral cortex, apical dendrites of pyramidal neurons form clusters which extend through several layers of the cortex also known as dendritic bundles. Previously, it has been shown that 5-HT3A receptor knockout mice show hypercomplex apical dendrites of cortical

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

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    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.

  15. Dendritic Cells Expressing Plasmacytoid Marker PDCA-1 Are Trojan Horses during Toxoplasma gondii Infection1

    Science.gov (United States)

    Bierly, Allison L.; Shufesky, William J.; Sukhumavasi, Woraporn; Morelli, Adrian E.; Denkers, Eric Y.

    2009-01-01

    Plasmacytoid dendritic cells (pDCs) play a key role in the innate immune response to viral infection, due largely to their ability to produce large quantities of type I IFNs. These cells are also notable for their ability to differentiate into conventional dendritic cells after appropriate stimulation. Here, we show that a splenic population of murine CD11c+ cells expressing pDC markers Gr-1, B220, and PDCA-1 is preferentially parasitized after infection with the virulent RH strain of Toxoplasma gondii. Although these markers are closely associated with pDCs, the population we identified was unusual because the cells express CD11b and higher than expected levels of CD11c. By adoptive transfer of CD45.1-positive cells into CD45.2 congenic mice, we show that CD11c+Gr-1+ cells migrate from the peritoneal cavity to the spleen. During infection, these cells accumulate in the marginal zone region. Recruitment of infected CD11c+Gr-1+ cells to the spleen is partially dependent upon signaling through chemokine receptor CCR2. Intracellular cytokine staining demonstrates that infected, but not noninfected, splenic CD11c+Gr-1+ dendritic cells are suppressed in their ability to respond to ex vivo TLR stimulation. We hypothesize that Toxoplasma exploits pDCs as Trojan horses, targeting them for early infection, suppressing their cytokine effector function, and using them for dissemination within the host. PMID:19050266

  16. Dendritic cells expressing plasmacytoid marker PDCA-1 are Trojan horses during Toxoplasma gondii infection.

    Science.gov (United States)

    Bierly, Allison L; Shufesky, William J; Sukhumavasi, Woraporn; Morelli, Adrian E; Denkers, Eric Y

    2008-12-15

    Plasmacytoid dendritic cells (pDCs) play a key role in the innate immune response to viral infection, due largely to their ability to produce large quantities of type I IFNs. These cells are also notable for their ability to differentiate into conventional dendritic cells after appropriate stimulation. Here, we show that a splenic population of murine CD11c(+) cells expressing pDC markers Gr-1, B220, and PDCA-1 is preferentially parasitized after infection with the virulent RH strain of Toxoplasma gondii. Although these markers are closely associated with pDCs, the population we identified was unusual because the cells express CD11b and higher than expected levels of CD11c. By adoptive transfer of CD45.1-positive cells into CD45.2 congenic mice, we show that CD11c(+)Gr-1(+) cells migrate from the peritoneal cavity to the spleen. During infection, these cells accumulate in the marginal zone region. Recruitment of infected CD11c(+)Gr-1(+) cells to the spleen is partially dependent upon signaling through chemokine receptor CCR2. Intracellular cytokine staining demonstrates that infected, but not noninfected, splenic CD11c(+)Gr-1(+) dendritic cells are suppressed in their ability to respond to ex vivo TLR stimulation. We hypothesize that Toxoplasma exploits pDCs as Trojan horses, targeting them for early infection, suppressing their cytokine effector function, and using them for dissemination within the host.

  17. Dendritic cells and parasites: from recognition and activation to immune response instruction.

    Science.gov (United States)

    Motran, Claudia Cristina; Ambrosio, Laura Fernanda; Volpini, Ximena; Celias, Daiana Pamela; Cervi, Laura

    2017-02-01

    The effective defense against parasite infections requires the ability to mount an appropriate and controlled specific immune response able to eradicate the invading pathogen while limiting the collateral damage to self-tissues. 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. Ligation of dendritic cell pattern recognition receptors by pathogen-associated molecular pattern present in the parasites initiates signaling pathways that lead to the production of surface and secreted proteins that are required, together with the antigen, to induce an appropriate and timely regulated immune response. There is evidence showing that parasites can influence and regulate dendritic cell functions in order to promote a more permissive environment for their survival. In this review, we will focus on new insights about the ability of protozoan and helminth parasites or their products to modify dendritic cell function and discuss how this interaction is crucial in shaping the host response.

  18. Mucosal dendritic cells in HIV-1 susceptibility: a critical role for C-type lectin receptors

    NARCIS (Netherlands)

    Hertoghs, Nina; van Pul, Lisa; Geijtenbeek, Teunis B. H.

    2017-01-01

    Sexual transmission is the major route of HIV-1 infection worldwide. The interaction of HIV-1 with mucosal dendritic cells (DCs) might determine HIV-1 susceptibility as well as initial antiviral immunity controlling virus in the chronic phase. Different DC subsets reside in mucosal tissues and

  19. 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

  20. Subset of DC-SIGN(+) dendritic cells in human blood transmits HIV-1 to T lymphocytes

    NARCIS (Netherlands)

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

    2002-01-01

    The dendritic cell (DC)-specific molecule DC-SIGN is a receptor for the HIV-1 envelope glycoprotein gp120 and is essential for the dissemination of HIV-1. DC-SIGN is expressed by DCs, both monocyte-derived DCs and DCs in several tissues, including mucosa and lymph nodes. To identify a DC-SIGN(+) DC

  1. 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,

  2. Make immunological peace not war: Potential applications of tolerogenic dendritic cells

    Directory of Open Access Journals (Sweden)

    Emma Louise Walton

    2017-04-01

    Full Text Available In this issue of the Biomedical Journal, we explore the powerful immunosuppressive properties of tolerogenic dendritic cells and discuss their potential to bring about lifelong tolerance in transplantation and autoimmune disease. We also highlight an exciting new development in the field of malaria diagnosis that could facilitate early detection of the disease.

  3. 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

  4. 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...

  5. Closed system generation of dendritic cells from a single blood volume for clinical application in immunotherapy

    NARCIS (Netherlands)

    Elias, M; van Zanten, J; Hospers, GAP; Setroikromo, A; de Jong, MA; de Leij, LFMH; Mulder, NH

    2005-01-01

    Dendritic cells (DC) used for clinical trials should be processed oil a large scale conforming to current good manufacturing practice (cGM P) guidelines. The aim of this study was to develop a protocol for clinical grade generation of immature DC in a closed-systern. Aphereses were performed with

  6. 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

  7. SAMHD1 degradation enhances active suppression of dendritic cell maturation by HIV-1

    NARCIS (Netherlands)

    Hertoghs, Nina; van der Aar, Angelic M. G.; Setiawan, Laurentia C.; Kootstra, Neeltje A.; Gringhuis, Sonja I.; Geijtenbeek, Teunis B. H.

    2015-01-01

    A hallmark of HIV-1 infection is the lack of sterilizing immunity. Dendritic cells (DCs) are crucial in the induction of immunity, and lack of DC activation might underlie the absence of an effective anti-HIV-1 response. We have investigated how HIV-1 infection affects maturation of DCs. Our data

  8. Human plasmacytoid dendritic cells phagocytose, process, and present exogenous particulate antigen.

    NARCIS (Netherlands)

    Tel, J.; Lambeck, A.J.A.; Cruz, L.J.; Tacken, P.J.; Vries, I.J.M. de; Figdor, C.G.

    2010-01-01

    Plasmacytoid dendritic cells (pDCs) play a major role in shaping both innate and adaptive immune responses, mainly via their production of large amounts of type I IFNs. pDCs are considered to primarily present endogenous Ags and are thought not to participate in the uptake and presentation of Ags

  9. Isolation of IL-12p70-competent human monocyte-derived dendritic cells

    DEFF Research Database (Denmark)

    Søndergaard, Jonas Nørskov; Pedersen, Susanne Brix

    2012-01-01

    Diverse methodologies ranging from experimental immunological studies to immunotherapy involve the application of human monocyte-derived dendritic cells (moDCs). Considerable donor-dependent variations in the moDC production of IL-12p70 affect the outcome of these methodologies. It has been shown...

  10. Immunomodulatory properties of oat and barley β-glucan populations on bone marrow derived dendritic cells

    NARCIS (Netherlands)

    Rosch, Christiane; Meijerink, Marjolein; Delahaije, Roy J.B.M.; Taverne, Nico; Gruppen, Harry; Wells, Jerry M.; Schols, Henk A.

    2016-01-01

    Specific structures of oat and barley β(1,3)(1,4)-glucans induced different in vitro immunomodulatory effects in bone marrow derived dendritic cells (BMDC) from TLR2/4 knock out mice. All barley β-glucan fractions induced larger amounts of cytokines in BMDCs than their oat equivalents. The

  11. Optimization of Assays to Assess Dendritic Cell Activation and/or Energy in Ebola Infection

    Science.gov (United States)

    2011-10-01

    vaccines and therapeutics.  We developed and successfully employed assays to monitor attachment and entry of EBOV virus-like particles tagged with beta ... lactamase .  We demonstrated a strong preference for EBOV to enter macrophages and dendritic cells versus monocytes.  We provided evidence

  12. 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

  13. 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

  14. 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

  15. 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

  16. 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 cells * Borrelia burgdorferi * Tick cystatin * Signalling Subject RIV: EC - Immunology Impact factor: 3.234, year: 2015

  17. 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

  18. 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

  19. 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 cells * immunity Subject RIV: EC - Immunology Impact factor: 5.293, year: 2007

  20. GSK-3β Overexpression Alters the Dendritic Spines of Developmentally Generated Granule Neurons in the Mouse Hippocampal Dentate Gyrus

    Science.gov (United States)

    Pallas-Bazarra, Noemí; Kastanauskaite, Asta; Avila, Jesús; DeFelipe, Javier; Llorens-Martín, María

    2017-01-01

    The dentate gyrus (DG) plays a crucial role in hippocampal-related memory. The most abundant cellular type in the DG, namely granule neurons, are developmentally generated around postnatal day P6 in mice. Moreover, a unique feature of the DG is the occurrence of adult hippocampal neurogenesis, a process that gives rise to newborn granule neurons throughout life. Adult-born and developmentally generated granule neurons share some maturational aspects but differ in others, such as in their positioning within the granule cell layer. Adult hippocampal neurogenesis encompasses a series of plastic changes that modify the function of the hippocampal trisynaptic network. In this regard, it is known that glycogen synthase kinase 3β (GSK-3β) regulates both synaptic plasticity and memory. By using a transgenic mouse overexpressing GSK-3β in hippocampal neurons, we previously demonstrated that the overexpression of this kinase has deleterious effects on the maturation of newborn granule neurons. In the present study, we addressed the effects of GSK-3β overexpression on the morphology and number of dendritic spines of developmentally generated granule neurons. To this end, we performed intracellular injections of Lucifer Yellow in developmentally generated granule neurons of wild-type and GSK-3β-overexpressing mice and analyzed the number and morphologies of dendritic spines (namely, stubby, thin and mushroom). GSK-3β overexpression led to a general reduction in the number of dendritic spines. In addition, it caused a slight reduction in the percentage, head diameter and length of thin spines, whereas the head diameter of mushroom spines was increased. PMID:28344548

  1. 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

  2. Macropinocytosis in phagocytes: regulation of MHC class-II-restricted antigen presentation in dendritic cells

    OpenAIRE

    Liu, Zhenzhen; Roche, Paul A.

    2015-01-01

    AbstractDendritic cells (DCs) are outstanding antigen presenting cells (APCs) due to their robust ability to internalize extracellular antigens using endocytic processes such as receptor-mediated endocytosis, phagocytosis, and macropinocytosis. Macropinocytosis mediates the non-specific uptake of soluble antigens and occurs in DCs constitutively. Macropinocytosis plays a key role in DC-mediated antigen presentation to T cells against pathogens and the efficiency of macropinocytosis in antigen...

  3. Regulation of acquired immunity by gamma delta T-cell/dendritic-cell interactions.

    Science.gov (United States)

    Shrestha, Niraj; Ida, James A; Lubinski, A Steven; Pallin, Maria; Kaplan, Gilla; Haslett, Patrick A J

    2005-12-01

    In humans, innate immune recognition of mycobacteria, including Mycobacterium tuberculosis and Mycobacterium leprae, involves toll-like receptor-2 (TLR-2), expressed on immature dendritic cells (DCs), and the T-cell gammadelta receptor expressed by a subpopulation of T cells that utilize Vdelta2 (Vdelta2 T cells). To investigate modulatory relationships between these host-cell populations in a microbial context, in vitro experiments were performed with human DCs and Vdelta2 T cells stimulated with model TLR-2 ligands and phosphoantigens, respectively. We observed that TLR-2-stimulated DCs enhanced interferon-gamma (IFN-gamma) production by Vdelta2 T cells; conversely, activated Vdelta2 T cells enhanced TLR-2-induced DC maturation via soluble factors including IFN-gamma, which costimulated interleukin-12 (IL-12) p70 secretion by DCs. Exposure of DCs to activated Vdelta2 T cells was critical for Th1 T-cell priming when TLR-2 stimulation was limiting. These results suggest that Vdelta2 T cells may play an adjuvant role in priming protective antimycobacterial immunity when TLR-2 stimulation is lacking, as may occur if the infectious inoculum is small, or if the pathogen is an intrinsically weak activator of DCs.

  4. 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

  5. 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.

  6. Clinical responses in patients with advanced colorectal cancer to a dendritic cell based vaccine

    DEFF Research Database (Denmark)

    Burgdorf, Stefan K; Fischer, Anders; Myschetzky, Peter S

    2008-01-01

    on dendritic cells pulsed with an allogenic tumor cell lysate. Twenty patients with advanced colorectal cancer were consecutively enrolled. Dendritic cells (DC) were generated from autologous peripheral blood mononuclear cells and pulsed with allogenic tumor cell lysate containing high levels of cancer......-testis antigens. Vaccines were biweekly administered intradermally with a total of 10 vaccines per patient. CT scans were performed and responses were graded according to the RECIST criteria. Quality of life was monitored with the SF-36 questionnaire. Toxicity and adverse events were graded according...... to the National Cancer Institute's common Toxicity Criteria. Four patients were graded with stable disease. Two remained stable throughout the entire study period. Analysis of changes in the patients' quality of life revealed stability in the subgroups: 'physical function' (p=0.872), 'physical role limitation' (p...

  7. 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.

  8. Fusions of Breast Carcinoma and Dendritic Cells as a Vaccine for the Treatment of Metastatic Breast Cancer

    Science.gov (United States)

    2005-07-01

    AD Award Number: DAMD17-03-1-0487 TITLE: Fusions of Breast Carcinoma and Dendritic Cells as a Vaccine for the Treatment of Metastatic Breast Cancer...4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Fusions of Breast Carcinoma and Dendritic Cells as a Vaccine for the Treatment of Metastatic Breast Cancer... Borras -Cuesta, F., and Lasarte, J. J. CD4+/CD25+ regulatory cells inhibit activation of tumor-primed CD4+ T cells with IFN- gamma-dependent

  9. DSCAM Promotes Refinement in the Mouse Retina through Cell Death and Restriction of Exploring Dendrites

    Science.gov (United States)

    Li, Shuai; Sukeena, Joshua M.; Simmons, Aaron B.; Hansen, Ethan J.; Nuhn, Renee E.; Samuels, Ivy S.

    2015-01-01

    In this study we develop and use a gain-of-function mouse allele of the Down syndrome cell adhesion molecule (Dscam) to complement loss-of-function models. We assay the role of Dscam in promoting cell death, spacing, and laminar targeting of neurons in the developing mouse retina. We find that ectopic or overexpression of Dscam is sufficient to drive cell death. Gain-of-function studies indicate that Dscam is not sufficient to increase spatial organization, prevent cell-to-cell pairing, or promote active avoidance in the mouse retina, despite the similarity of the Dscam loss-of-function phenotype in the mouse retina to phenotypes observed in Drosophila Dscam1 mutants. Both gain- and loss-of-function studies support a role for Dscam in targeting neurites; DSCAM is necessary for precise dendrite lamination, and is sufficient to retarget neurites of outer retinal cells after ectopic expression. We further demonstrate that DSCAM guides dendrite targeting in type 2 dopaminergic amacrine cells, by restricting the stratum in which exploring retinal dendrites stabilize, in a Dscam dosage-dependent manner. Based on these results we propose a single model to account for the numerous Dscam gain- and loss-of-function phenotypes reported in the mouse retina whereby DSCAM eliminates inappropriately placed cells and connections. PMID:25855178

  10. A mouse model of adoptive immunotherapeutic targeting of autoimmune arthritis using allo-tolerogenic dendritic cells.

    Directory of Open Access Journals (Sweden)

    Jie Yang

    Full Text Available OBJECTIVE: Tolerogenic dendritic cells (tDCs are immunosuppressive cells with potent tolerogenic ability and are promising immunotherapeutic tools for treating rheumatoid arthritis (RA. However, it is currently unknown whether allogeneic tDCs (allo-tDCs induce tolerance in RA, and whether the numbers of adoptively transferred allo-tDCs, or the requirement for pulsing with relevant auto-antigens are important. METHODS: tDCs were derived from bone marrow precursors of C57BL/B6 mice, which were induced in vitro by GM-CSF, IL-10 and TGF-β1. Collagen-induced arthritis (CIA was modeled in D1 mice by immunization with type II collagen (CII to test the therapeutic ability of allo-tDCs against CIA. Clinical and histopathologic scores, arthritic incidence, cytokine and anti-CII antibody secretion, and CD4(+Th subsets were analyzed. RESULTS: tDCs were characterized in vitro by a stable immature phonotype and a potent immunosuppressive ability. Following adoptive transfer of low doses (5×10(5 of CII-loaded allo-tDCs, a remarkable anti-arthritic activity, improved clinical scores and histological end-points were found. Serological levels of inflammatory cytokines and anti-CII antibodies were also significantly lower in CIA mice treated with CII-pulsed allo-tDCs as compared with allo-tDCs. Moreover, treatment with allo-tDCs altered the proportion of Treg/Th17 cells. CONCLUSION: These findings suggested that allo-tDCs, especially following antigen loading, reduced the severity of CIA in a dose-dependent manner. The dampening of CIA was associated with modulated cytokine secretion, Treg/Th17 polarization and inhibition of anti-CII secretion. This study highlights the potential therapeutic utility of allo-tDCs in autoimmune arthritis and should facilitate the future design of allo-tDC immunotherapeutic strategies against RA.

  11. Blood dendritic cell frequency declines in idiopathic Parkinson's disease and is associated with motor symptom severity.

    Directory of Open Access Journals (Sweden)

    Antonio Ciaramella

    Full Text Available The role of inflammation in Parkinson's Disease (PD is well appreciated, but its underlying mechanisms are still unclear. Our objective was to determine whether dendritic cells (DC, a unique type of migratory immune cells that regulate immunological response and inflammation have an impact on PD. In a case-control study including 80 PD patients and 80 age- and gender-matched healthy control subjects, the two main blood subsets of plasmacytoid and myeloid DC were defined by flow cytometry analysis. Clinical evaluation of subjects consisting of cognition and depression assessment was performed using the Mini Mental State Examination and the Beck Depression Inventory. The severity of motor symptoms was measured using the Unified Parkinson's Disease Rating Scale-Part III. Comparison between patient and control DC measures and their relationships with clinical assessments were evaluated.The following main results were obtained: 1 the level of circulating DC (mainly the myeloid subset was significantly reduced in PD patients in comparison with healthy controls; 2 after controlling for depressive and cognitive characteristics, the frequency of myeloid DC was confirmed as one of the independent determinants of PD; 3 the number of both myeloid and plasmacytoid DC was negatively associated with motor symptom severity. Overall, the decline of blood DC, perhaps due to the recruitment of immune cells to the site of disease-specific lesions, can be considered a clue of the immune alteration that characterizes PD, suggesting innovative exploitations of DC monitoring as a clinically significant tool for PD treatment. Indeed, this study suggests that reduced peripheral blood DC are a pathologically-relevant factor of PD and also displays the urgency to better understand DC role in PD for unraveling the immune system contribution to disease progression and thus favoring the development of innovative therapies ideally based on immunomodulation.

  12. The intestinal archaea Methanosphaera stadtmanae and Methanobrevibacter smithii activate human dendritic cells.

    Directory of Open Access Journals (Sweden)

    Corinna Bang

    Full Text Available The methanoarchaea Methanosphaera stadtmanae and Methanobrevibacter smithii are known to be part of the indigenous human gut microbiota. Although the immunomodulatory effects of bacterial gut commensals have been studied extensively in the last decade, the impact of methanoarchaea in human's health and disease was rarely examined. Consequently, we studied and report here on the effects of M. stadtmanae and M. smithii on human immune cells. Whereas exposure to M. stadtmanae leads to substantial release of proinflammatory cytokines in monocyte-derived dendritic cells (moDCs, only weak activation was detected after incubation with M. smithii. Phagocytosis of M. stadtmanae by moDCs was demonstrated by confocal microscopy as well as transmission electronic microscopy (TEM and shown to be crucial for cellular activation by using specific inhibitors. Both strains, albeit to different extents, initiate a maturation program in moDCs as revealed by up-regulation of the cell-surface receptors CD86 and CD197 suggesting additional activation of adaptive immune responses. Furthermore, M. stadtmanae and M. smithii were capable to alter the gene expression of antimicrobial peptides in moDCs to different extents. Taken together, our findings strongly argue that the archaeal gut inhabitants M. stadtmanae and M. smithii are specifically recognized by the human innate immune system. Moreover, both strains are capable of inducing an inflammatory cytokine response to different extents arguing that they might have diverse immunomodulatory functions. In conclusion, we propose that the impact of intestinal methanoarchaea on pathological conditions involving the gut microbiota has been underestimated until now.

  13. Differential responses of human dendritic cells to metabolites from the oral/airway microbiome.

    Science.gov (United States)

    Whiteson, K; Agrawal, S; Agrawal, A

    2017-06-01

    Small molecule metabolites that are produced or altered by host-associated microbial communities are emerging as significant immune response modifiers. However, there is a key gap in our knowledge of how oral microbial metabolites affect the immune response. Here, we examined the effects of metabolites from five bacterial strains found commonly in the oral/airway microbial communities of humans. The five strains, each isolated from cystic fibrosis patient sputum, were Pseudomonas aeruginosa FLR01 non-mucoid (P1) and FLR02 mucoid (P2) forms, Streptococcus pneumoniae (Sp), S. salivarius (Ss) and Rothia mucilaginosa (Rm). The effect of bacterial metabolites on dendritic cell (DC) activation, T cell priming and cytokine secretion was determined by exposing DCs to bacterial supernatants and individual metabolites of interest. Supernatants from P1 and P2 induced high levels of tumour necrosis factor (TNF)-α, interleukin (IL)-12 and IL-6 from DCs and primed T cells to secrete interferon (IFN)-γ, IL-22 compared to supernatants from Sp, Ss and Rm. Investigations into the composition of supernatants using gas chromatography-mass spectroscopy (GC-MS) revealed signature metabolites for each of the strains. Supernatants from P1 and P2 contained high levels of putrescine and glucose, while Sp and Ss contained high levels of 2,3-butanediol. The individual metabolites replicated the results of whole supernatants, although the magnitudes of their effects were reduced significantly. Altogether, our data demonstrate for the first time that the signature metabolites produced by different bacteria have different effects on DC functions. The identification of signature metabolites and their effects on the host immune system can provide mechanistic insights into diseases and may also be developed as biomarkers. © 2017 British Society for Immunology.

  14. T cell-derived IL-10 determines leishmaniasis disease outcome and is suppressed by a dendritic cell based vaccine.

    Science.gov (United States)

    Schwarz, Tobias; Remer, Katharina A; Nahrendorf, Wiebke; Masic, Anita; Siewe, Lisa; Müller, Werner; Roers, Axel; Moll, Heidrun

    2013-01-01

    In the murine model of Leishmania major infection, resistance or susceptibility to the parasite has been associated with the development of a Th1 or Th2 type of immune response. Recently, however, the immunosuppressive effects of IL-10 have been ascribed a crucial role in the development of the different clinical correlates of Leishmania infection in humans. Since T cells and professional APC are important cellular sources of IL-10, we compared leishmaniasis disease progression in T cell-specific, macrophage/neutrophil-specific and complete IL-10-deficient C57BL/6 as well as T cell-specific and complete IL-10-deficient BALB/c mice. As early as two weeks after infection of these mice with L. major, T cell-specific and complete IL-10-deficient animals showed significantly increased lesion development accompanied by a markedly elevated secretion of IFN-γ or IFN-γ and IL-4 in the lymph nodes draining the lesions of the C57BL/6 or BALB/c mutants, respectively. In contrast, macrophage/neutrophil-specific IL-10-deficient C57BL/6 mice did not show any altered phenotype. During the further course of disease, the T cell-specific as well as the complete IL-10-deficient BALB/c mice were able to control the infection. Furthermore, a dendritic cell-based vaccination against leishmaniasis efficiently suppresses the early secretion of IL-10, thus contributing to the control of parasite spread. Taken together, IL-10 secretion by T cells has an influence on immune activation early after infection and is sufficient to render BALB/c mice susceptible to an uncontrolled Leishmania major infection.

  15. 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.

  16. 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.

  17. Dendritic cells derived from HOXB4-immortalized hematopoietic bone marrow cells.

    Science.gov (United States)

    Baru, Abdul Mannan; Krishnaswamy, Jayendra Kumar; Rathinasamy, Anchana; Scherr, Michaela; Eder, Matthias; Behrens, Georg M N

    2011-11-01

    Dendritic cells (DCs) are essential for the generation and modulation of cell-mediated adaptive immunity against infections. DC-based vaccination involves transplantation of ex vivo-generated DCs loaded with antigen in vitro, but remains limited by the number of autologous or allogeneic cells. While in vitro expansion and differentiation of hematopoietic stem cells (HSCs) into DCs seems to be the most viable alternative to overcome this problem, the complexity of HSC expansion in vitro has posed significant limitations for clinical application. We immortalized lineage-depleted murine hematopoietic bone marrow (lin(-)BM) cells with HOXB4, and differentiated them into CD11c(+)MHCII(+) DCs. These cells showed the typical DC phenotype and upregulated surface expression of co-stimulatory molecules on stimulation with various toll-like receptor ligands. These DCs efficiently presented exogenous antigen to T-cells via major histocompatibility complex (MHC) I and II and viral antigen on infection. Finally, they showed migratory capacity and were able to generate antigen-specific primed T-cells in vivo. In summary, we provide evidence that HOXB4-transduced lin(-)BM cells can serve as a viable means of generating fully functional DCs for scientific and therapeutic applications.

  18. Dendritic cell type-specific HIV-1 activation in effector T cells: implications for latent HIV-1 reservoir establishment

    NARCIS (Netherlands)

    van der Sluis, Renée M.; van Capel, Toni M. M.; Speijer, Dave; Sanders, Rogier W.; Berkhout, Ben; de Jong, Esther C.; Jeeninga, Rienk E.; van Montfort, Thijs

    2015-01-01

    Latent HIV type I (HIV-1) infections can frequently occur in short-lived proliferating effector T lymphocytes. These latently infected cells could revert into resting T lymphocytes and thereby contribute to the establishment of the long-lived viral reservoir. Monocyte-derived dendritic cells can

  19. C-type lectin Mermaid inhibits dendritic cell mediated HIV-1 transmission to CD4+ T cells

    NARCIS (Netherlands)

    Nabatov, Alexey A.; de Jong, Marein A. W. P.; de Witte, Lot; Bulgheresi, Silvia; Geijtenbeek, Teunis B. H.

    2008-01-01

    Dendritic cells (DCs) are important in HIV-1 transmission; DCs capture invading HIV-1 through the interaction of the gp120 oligosaccharides with the C-type lectin DC-SIGN and migrate to the lymphoid tissues where HIV-1 is transmitted to T cells. Thus, the HIV-1 envelope glycoprotein gp120 is an

  20. Vitamin D3 metabolite calcidiol primes human dendritic cells to promote the development of immunomodulatory IL-10-producing T cells

    NARCIS (Netherlands)

    Bakdash, Ghaith; van Capel, Toni M. M.; Mason, Lauren M. K.; Kapsenberg, Martien L.; de Jong, Esther C.

    2014-01-01

    Vitamin D is recognized as a potent immunosuppressive drug. The suppressive effects of vitamin D are attributed to its physiologically active metabolite 1,25 dihydroxy vitamin D3 (calcitriol), which was shown, to prime dendritic cells (DCs) to promote the development of regulatory T (Treg) cells.

  1. 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

  2. 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

  3. 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.

  4. 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

  5. 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 regulatory T cell 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.

  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. 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.

  8. 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.

  9. The Dendritic Cell Synapse: A Life Dedicated to T Cell Activation.

    Science.gov (United States)

    Benvenuti, Federica

    2016-01-01

    T-cell activation within immunological synapses is a complex process whereby different types of signals are transmitted from antigen-presenting cells to T cells. The molecular strategies developed by T cells to interpret and integrate these signals have been systematically dissected in recent years and are now in large part understood. On the other side of the immune synapse, dendritic cells (DCs) participate actively in synapse formation and maintenance by remodeling of membrane receptors and intracellular content. However, the details of such changes have been only partially characterized. The DCs actin cytoskeleton has been one of the first systems to be identified as playing an important role in T-cell priming and some of the underlying mechanisms have been elucidated. Similarly, the DCs microtubule cytoskeleton undergoes major spatial changes during synapse formation that favor polarization of the DCs subcellular space toward the interacting T cell. Recently, we have begun to investigate the trafficking machinery that controls polarized delivery of endosomal vesicles at the DC-T immune synapse with the aim of understanding the functional relevance of polarized secretion of soluble factors during T-cell priming. Here, we will review the current knowledge of events occurring in DCs during synapse formation and discuss the open questions that still remain unanswered.

  10. 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

  11. Dendritic Cells Produce CXCL13 and Participate in the Development of Murine Small Intestine Lymphoid Tissues

    OpenAIRE

    McDonald, Keely G.; McDonough, Jacquelyn S.; Dieckgraefe, Brian K.; Newberry, Rodney D.

    2010-01-01

    In the adult intestine, luminal microbiota induce cryptopatches to transform into isolated lymphoid follicles (ILFs), which subsequently act as sites for the generation of IgA responses. The events leading to this conversion are incompletely understood. Dendritic cells (DCs) are components of cryptopatches (CPs) and ILFs and were therefore evaluated in this process. We observed that the adult murine intestine contains clusters of DCs restricted to the CP/ILF continuum. A numerical and cell as...

  12. Lactobacilli differentially modulate expression of cytokines and maturation surface markers in murine dendritic cells

    DEFF Research Database (Denmark)

    Christensen, Hanne Risager; Frøkiær, Hanne; Pestka, J.J.

    2002-01-01

    Dendritic cells (DC) play a pivotal immunoregulatory role in the Th1, Th2, and Th3 cell balance and are present throughout the gastrointestinal tract. Thus, DC may be targets for modulation by gut microbes, including ingested probiotics. In the present study, we tested the hypothesis that species......-driving capacities of the gut DC to be modulated according to composition of gut microflora, including ingested probiotics....

  13. The Effect of Histamine on Dendritic Cells Pulsed with Myelin Proteins and Autologous T Cell Response in Vitro

    Directory of Open Access Journals (Sweden)

    H Mohebalian

    2013-07-01

    Full Text Available Abstract Background & aim: The role of dendritic cells in the immune responses has led to the application of these cells in autoimmune diseases such as multiple sclerosis. The aim of this study was to investigate the effect of histamine on dendritic cells pulsed with myelin proteins and autologous T cell response in vitro. Methods: In this experimental study, blood samples were taken from 5 volunteers. Subsequently, peripheral blood mononuclear cells were isolated by using Phicole Hypaque. Using GM-CSF cytokine and IL-4, dendritic cells were produced from peripheral blood and then stimulated with MBP in the presence and without histamine in control and treated group to be matured. The CD14+ and surface markers of resulted DC were evaluated by Flowcytometry. The levels of cytokines IL-10 and IL-12 in dendritic cells culture and IL-4, and IFN-γ in both cultured dendritic cells and antilogous T cells were obtained. And then the proliferation of T lymphocytes in the treatment and control groups were compared. The collected data was analyzed by Student's t-test and ANOVA. Results: In the treatment group, the expression of CD83 (from 3/15 to 5/24% and HLA-DR (from 3/26 to 38% was significantly higher than the control group (P> 0.05. The expression of CD14 exhibited no change. The secretion of IL-10 increased and IL-12 showed a decrease. The secretion of IL-4/IFN- ᵞ showed an increase in treated group than the control group (P ˂ 0/05. Conclusion: Histamine deviation with immune responses from TH1/TH17 to the TH2 in an experimental model of MS can be used as a new method of DC-based vaccines which may be useful in treating this disease. Key words: Denderitic Cells, Myelin Basic Protein (MBP, Histamine, Multiple sclerosis (MS

  14. 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.

  15. Aminopeptidase N (CD13 Is Involved in Phagocytic Processes in Human Dendritic Cells and Macrophages

    Directory of Open Access Journals (Sweden)

    Mónica I. Villaseñor-Cardoso

    2013-01-01

    Full Text Available Aminopeptidase N (APN or CD13 is a membrane ectopeptidase expressed by many cell types, including myelomonocytic lineage cells: monocytes, macrophages, and dendritic cells. CD13 is known to regulate the biological activity of various peptides by proteolysis, and it has been proposed that CD13 also participates in several functions such as angiogenesis, cell adhesion, metastasis, and tumor invasion. We had previously reported that, in human monocytes and macrophages, CD13 modulates the phagocytosis mediated by receptors for the Fc portion of IgG antibodies (FcγRs. In this work, we analyzed the possible interaction of CD13 with other phagocytic receptors. We found out that the cross-linking of CD13 positively modulates the phagocytosis mediated by receptors of the innate immune system, since a significant increase in the phagocytosis of zymosan particles or heat-killed E. coli was observed when CD13 was cross-linked using anti-CD13 antibodies, in both macrophages and dendritic cells. Also, we observed that, during the phagocytosis of zymosan, CD13 redistributes and is internalized into the phagosome. These findings suggest that, besides its known functions, CD13 participates in phagocytic processes in dendritic cells and macrophages.

  16. MHC class II distribution in dendritic cells and B cells is determined by ubiquitin chain length

    Science.gov (United States)

    Ma, Jessica K.; Platt, Mia Y.; Eastham-Anderson, Jeffrey; Shin, Jeoung-Sook; Mellman, Ira

    2012-01-01

    Dendritic cells (DCs) and B cells present antigen-derived peptides bound to MHC class II (MHC II) molecules for recognition by CD4-positive T lymphocytes. DCs control the intracellular traffic of peptide–MHC II complexes by regulating the ubiquitination of MHC II. In resting or “immature” DCs, ubiquitinated MHC II molecules are targeted to lysosomes, but upon pathogen-induced “maturation,” ubiquitination is down-regulated and MHC II can accumulate on the plasma membrane of mature DCs. Although B cells constitutively ubiquitinate their MHC II, it unexpectedly remains at the surface. We find that DCs and B cells differ in MHC II-conjugated ubiquitin (Ub) chain length: four to six Ub in immature DCs vs. two to three in B cells. In both cell types, experimentally increasing Ub chain length led to efficient lysosomal transport of MHC II, whereas MHC II with fewer than two Ubs did not reach lysosomes. Thus, Ub chain length plays a crucial role in regulating the intracellular fate and function of MHC II in DCs and B cells. PMID:22566640

  17. Immunotherapy with dendritic cells in an animal model of early pulmonary metastatic squamous cell carcinoma.

    Science.gov (United States)

    Moon, Jeong Hwan; Chung, Man Ki; Son, Young-Ik

    2012-11-01

    Distant metastases is becoming a more frequently recognized pattern of treatment failure in patients with squamous cell carcinoma of the head and neck (SCCHN). In this study, we evaluated the effect of a dendritic cell (DC)-based vaccine in an early pulmonary metastatic murine model with the aim of providing an effective treatment for SCCHN patients presenting with occult pulmonary metastasis. In vivo animal experiments were conducted in C3H/He immunocompetent mice using the SCCVII syngeneic squamous carcinoma cell line. SCCVII cells were injected through the tail vein to establish early pulmonary metastases. Bone marrow-derived DCs were cultured and educated with ultraviolet B-irradiated apoptotic SCCVII cells before adoptive transfer into the inguinal area. Control groups were vaccinated with normal saline, naïve DCs, or apoptotic tumor cells. In the apoptotic SCCVII-pulsed DC group, the number of pulmonary tumor nodules was reduced, extirpated lung weight was less, and survival was longer than in control groups. Differences were statistically significant (P cells. We hope this study will help improve overall survival of patients with SCCHN, especially when they have early or occult pulmonary metastasis. Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.

  18. Scrapie affects the maturation cycle and immune complex trapping by follicular dendritic cells in mice.

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    Gillian McGovern

    2009-12-01

    Full Text Available Transmissible spongiform encephalopathies (TSEs or prion diseases are infectious neurological disorders of man and animals, characterised by abnormal disease-associated prion protein (PrP(d accumulations in the brain and lymphoreticular system (LRS. Prior to neuroinvasion, TSE agents often accumulate to high levels within the LRS, apparently without affecting immune function. However, our analysis of scrapie-affected sheep shows that PrP(d accumulations within the LRS are associated with morphological changes to follicular dendritic cells (FDCs and tingible body macrophages (TBMs. Here we examined FDCs and TBMs in the mesenteric lymph nodes (MLNs of scrapie-affected mice by light and electron microscopy. In MLNs from uninfected mice, FDCs could be morphologically categorised into immature, mature and regressing forms. However, in scrapie-affected MLNs this maturation cycle was adversely affected. FDCs characteristically trap and retain immune complexes on their surfaces, which they display to B-lymphocytes. In scrapie-affected MLNs, some FDCs were found where areas of normal and abnormal immune complex retention occurred side by side. The latter co-localised with PrP(d plasmalemmal accumulations. Our data suggest this previously unrecognised morphology represents the initial stage of an abnormal FDC maturation cycle. Alterations to the FDCs included PrP(d accumulation, abnormal cell membrane ubiquitin and excess immunoglobulin accumulation. Regressing FDCs, in contrast, appeared to lose their membrane-attached PrP(d. Together, these data suggest that TSE infection adversely affects the maturation and regression cycle of FDCs, and that PrP(d accumulation is causally linked to the abnormal pathology observed. We therefore support the hypothesis that TSEs cause an abnormality in immune function.

  19. Chemokine regulation in response to beryllium exposure in human peripheral blood mononuclear and dendritic cells

    International Nuclear Information System (INIS)

    Hong-Geller, Elizabeth; Pardington, Paige E.; Cary, Robert B.; Sauer, Nancy N.; Gupta, Goutam

    2006-01-01

    Exposure to beryllium (Be) induces a delayed-type hypersensitivity immune reaction in the lungs of susceptible individuals, which leads to the onset of Be sensitivity and Chronic Beryllium Disease (CBD). Although some mechanistic aspects of CBD have begun to be characterized, very little is known about the molecular mechanisms by which Be activates the host immune response. To gain insight into the cellular response to Be exposure, we have performed global microarray analysis using a mixture of peripheral blood mononuclear and dendritic cells (PBMC/DCs) from a non-CBD source to identify genes that are specifically upregulated in response to BeSO 4 stimulation, compared to a control metal salt, Al 2 (SO 4 ) 3 . We identified a number of upregulated immunomodulatory genes, including several chemokines in the MIP-1 and GRO families. Using PBMC/DCs from three different donors, we demonstrate that BeSO 4 stimulation generally exhibits an increased rate of both chemokine mRNA transcription and release compared to Al 2 (SO 4 ) 3 exposure, although variations among the individual donors do exist. We show that MIP-1α and MIP-1β neutralizing antibodies can partially inhibit the ability of BeSO 4 to stimulate cell migration of PBMC/DCs in vitro. Finally, incubation of PBMC/DCs with BeSO 4 altered the binding of the transcription factor RUNX to the MIP-1α promoter consensus sequence, indicating that Be can regulate chemokine gene activation. Taken together, these results suggest a model in which Be stimulation of PBMC/DCs can modulate the expression and release of different chemokines, leading to the migration of lymphocytes to the lung and the formation of a localized environment for development of Be disease in susceptible individuals

  20. Chemokine regulation in response to beryllium exposure in human peripheral blood mononuclear and dendritic cells.

    Science.gov (United States)

    Hong-Geller, Elizabeth; Pardington, Paige E; Cary, Robert B; Sauer, Nancy N; Gupta, Goutam

    2006-02-01

    Exposure to beryllium (Be) induces a delayed-type hypersensitivity immune reaction in the lungs of susceptible individuals, which leads to the onset of Be sensitivity and Chronic Beryllium Disease (CBD). Although some mechanistic aspects of CBD have begun to be characterized, very little is known about the molecular mechanisms by which Be activates the host immune response. To gain insight into the cellular response to Be exposure, we have performed global microarray analysis using a mixture of peripheral blood mononuclear and dendritic cells (PBMC/DCs) from a non-CBD source to identify genes that are specifically upregulated in response to BeSO(4) stimulation, compared to a control metal salt, Al(2)(SO(4))(3). We identified a number of upregulated immunomodulatory genes, including several chemokines in the MIP-1 and GRO families. Using PBMC/DCs from three different donors, we demonstrate that BeSO(4) stimulation generally exhibits an increased rate of both chemokine mRNA transcription and release compared to Al(2)(SO(4))(3) exposure, although variations among the individual donors do exist. We show that MIP-1 alpha and MIP-1 beta neutralizing antibodies can partially inhibit the ability of BeSO(4) to stimulate cell migration of PBMC/DCs in vitro. Finally, incubation of PBMC/DCs with BeSO(4) altered the binding of the transcription factor RUNX to the MIP-1 alpha promoter consensus sequence, indicating that Be can regulate chemokine gene activation. Taken together, these results suggest a model in which Be stimulation of PBMC/DCs can modulate the expression and release of different chemokines, leading to the migration of lymphocytes to the lung and the formation of a localized environment for development of Be disease in susceptible individuals.

  1. Novel immunomodulators from hard ticks selectively reprogramme human dendritic cell responses.

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    Stephen G Preston

    Full Text Available Hard ticks subvert the immune responses of their vertebrate hosts in order to feed for much longer periods than other blood-feeding ectoparasites; this may be one reason why they transmit perhaps the greatest diversity of pathogens of any arthropod vector. Tick-induced immunomodulation is mediated by salivary components, some of which neutralise elements of innate immunity or inhibit the development of adaptive immunity. As dendritic cells (DC trigger and help to regulate adaptive immunity, they are an ideal target for immunomodulation. However, previously described immunoactive components of tick saliva are either highly promiscuous in their cellular and molecular targets or have limited effects on DC. Here we address the question of whether the largest and globally most important group of ticks (the ixodid metastriates produce salivary molecules that specifically modulate DC activity. We used chromatography to isolate a salivary gland protein (Japanin from Rhipicephalus appendiculatus ticks. Japanin was cloned, and recombinant protein was produced in a baculoviral expression system. We found that Japanin specifically reprogrammes DC responses to a wide variety of stimuli in vitro, radically altering their expression of co-stimulatory and co-inhibitory transmembrane molecules (measured by flow cytometry and their secretion of pro-inflammatory, anti-inflammatory and T cell polarising cytokines (assessed by Luminex multiplex assays; it also inhibits the differentiation of DC from monocytes. Sequence alignments and enzymatic deglycosylation revealed Japanin to be a 17.7 kDa, N-glycosylated lipocalin. Using molecular cloning and database searches, we have identified a group of homologous proteins in R. appendiculatus and related species, three of which we have expressed and shown to possess DC-modulatory activity. All data were obtained using DC generated from at least four human blood donors, with rigorous statistical analysis. Our results suggest

  2. Haloperidol suppresses murine dendritic cell maturation and priming of the T helper 1-type immune response.

    Science.gov (United States)

    Matsumoto, Atsuhiro; Ohta, Noriyuki; Goto, Yukiko; Kashiwa, Yozo; Yamamoto, Shunsuke; Fujino, Yuji

    2015-04-01

    Haloperidol has immunomodulatory effects when used to treat patients with schizophrenia and also is used to sedate critically ill patients in the intensive care unit. Although the mechanism by which haloperidol affects immune function is unclear, one possibility is that it alters dendritic cell (DC) function. DCs are potent antigen-presenting cells that influence the activation and maturation of T lymphocytes. In this study, we investigated the in vitro and in vivo immunomodulatory effects of haloperidol on DC-mediated immune responses. Using bone marrow-derived DCs in cell culture, we evaluated the effect of haloperidol on expression of costimulatory molecules (CD80 and CD86), major histocompatibility complex class ΙІ molecules, and the DC maturation marker CD83. DC culture supernatants also were evaluated for interleukin-12 p40 levels. In addition, we analyzed the effect of haloperidol on a mixed cell culture containing DCs and lymphocytes and measured the secretion of interferon-γ in the culture supernatants. We also assessed the in vivo effects of haloperidol on hapten-induced contact hypersensitivity responses. Haloperidol inhibited the expression of CD80, CD86, major histocompatibility complex class ΙІ, and CD83 molecules on DCs and the secretion of interleukin-12p40 in DC culture supernatants. In mixed cell cultures containing both T cells (CD4 and CD8α) and DCs, haloperidol-treated DCs suppressed the proliferation of allogeneic T cells and effectively inhibited the production of interferon-γ. In vivo, haloperidol reduced hapten-induced contact hypersensitivity responses. Furthermore, an antagonist to D2-like receptor suppressed the maturation of DCs in a manner similar to haloperidol. The results of our study suggest that haloperidol suppresses the functional maturation of DCs and plays an important role in the inhibition of DC-induced T helper 1 immune responses in the whole animal. Furthermore, the effect of haloperidol on DCs may be mediated by

  3. Fasciola hepatica glycoconjugates immuneregulate dendritic cells through the Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Non-integrin inducing T cell anergy.

    Science.gov (United States)

    Rodríguez, Ernesto; Kalay, Hakan; Noya, Verónica; Brossard, Natalie; Giacomini, Cecilia; van Kooyk, Yvette; García-Vallejo, Juan J; Freire, Teresa

    2017-04-24

    Dendritic cell-specific ICAM-3 grabbing non-integrin (DC-SIGN) expressed on a variety of DCs, is a C-type lectin receptor that recognizes glycans on a diverse range of pathogens, including parasites. The interaction of DC-SIGN with pathogens triggers specific signaling events that modulate DC-maturation and activity and regulate T-cell activation by DCs. In this work we evaluate whether F. hepatica glycans can immune modulate DCs via DC-SIGN. We demonstrate that DC-SIGN interacts with F. hepatica glycoconjugates through mannose and fucose residues. We also show that mannose is present in high-mannose structures, hybrid and trimannosyl N-glycans with terminal GlcNAc. Furthermore, we demonstrate that F. hepatica glycans induce DC-SIGN triggering leading to a strong production of TLR-induced IL-10 and IL-27p28. In addition, parasite glycans induced regulatory DCs via DC-SIGN that decrease allogeneic T cell proliferation, via the induction of anergic/regulatory T cells, highlighting the role of DC-SIGN in the regulation of innate and adaptive immune responses by F. hepatica. Our data confirm the immunomodulatory properties of DC-SIGN triggered by pathogen-derived glycans and contribute to the identification of immunomodulatory glyans of helminths that might eventually be useful for the design of vaccines against fasciolosis.

  4. Human C-reactive protein activates monocyte-derived dendritic cells and induces dendritic cell-mediated T-cell activation.

    Science.gov (United States)

    Van Vré, Emily A; Bult, Hidde; Hoymans, Vicky Y; Van Tendeloo, Viggo F I; Vrints, Christiaan J; Bosmans, Johan M

    2008-03-01

    Recent studies proposed a pathogenic role for C-reactive protein (CRP), an independent predictor of cardiovascular disease (CVD), in atherosclerosis. Therefore, we tested whether CRP may modulate dendritic cell (DC) function, because these professional antigen-presenting cells have been implicated in atherogenesis. Human monocyte-derived immature DCs were cultured with human CRP (0 to 60 microg/mL) for 24 hours. Thereafter, activation markers were measured by flow-cytometry and DCs were cocultured with CFSE-labeled lymphocytes to measure T-cell proliferation and interferon (IFN)-gamma secretion after 8 days. Exposure to 60 microg/mL CRP (n=5) induced an activated cell morphology and significant (CD40 increase MFI 5.23+/-0.28, PLPS). Polymyxin B abolished the LPS response, without influencing CRP effects. Finally, immunohistochemistry could demonstrate DC/CRP colocalization in human atherosclerotic lesions. These findings suggest that CRP in plaques or found circulating in CVD patients can influence DC function during atherogenesis.

  5. Vaccinia virus inhibits the maturation of human dendritic cells: a novel mechanism of immune evasion.

    Science.gov (United States)

    Engelmayer, J; Larsson, M; Subklewe, M; Chahroudi, A; Cox, W I; Steinman, R M; Bhardwaj, N

    1999-12-15

    Vaccinia virus employs multiple mechanisms to evade the immune system, yet is highly immunogenic. We studied the interaction between vaccinia and human dendritic cells (DCs), potent APCs. DCs develop from precursor cells in two stages: an immature stage in which Ag uptake and processing occur, and a mature stage in which there is up-regulation of costimulatory and HLA molecules and efficient T cell activation. Vaccinia virus undergoes an abortive replication in both stages of DCs and induces apoptotic cell death. Furthermore, maturation of immature DCs and consequently T cell activation are inhibited. Obstruction of DC maturation may constitute a novel mechanism by which vaccinia attempts to evade the immune response.

  6. Intraventricular administration of substance p increases the dendritic arborisation and the synaptic surfaces of Purkinje cells in rat's cerebellum.

    Science.gov (United States)

    Baloyannis, S J; Costa, V; Deretzi, G; Michmizos, D

    2000-01-01

    Substance P was infused in the lateral ventricles of twenty Lewis rats for twenty days. On the twentieth day the animals were sacrificed and the cerebellar cortex was processed for electron microscopy. The ultrastructural morphometric analysis revealed that the Purkinje cell dendritic arborisation and the number of the synapses between the parallel fibres and the Purkinje cell dendritic spines were much higher than in control animals. Numerous unattached spines of the secondary and tertiary dendritic branches of the Purkinje cells were also seen in the molecular layer either free or surrounded by astrocytic sheath. The increased number of synapses between the Purkinje cell dendrites and the parallel fibres in the animals, which received substance P intraventricularly, in correlation to control animals, supports a neurotrophine-like activity of the substance P in the mammalian cerebellum, enforcing the pre-programmed capability of the Purkinje cells to develop new synaptic surfaces.

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

    Science.gov (United States)

    2012-01-01

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

  8. Migratory dermal dendritic cells act as rapid sensors of protozoan parasites.

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    Lai Guan Ng

    2008-11-01

    Full Text Available Dendritic cells (DC, including those of the skin, act as sentinels for intruding microorganisms. In the epidermis, DC (termed Langerhans cells, LC are sessile and screen their microenvironment through occasional movements of their dendrites. The spatio-temporal orchestration of antigen encounter by dermal DC (DDC is not known. Since these cells are thought to be instrumental in the initiation of immune responses during infection, we investigated their behavior directly within their natural microenvironment using intravital two-photon microscopy. Surprisingly, we found that, under homeostatic conditions, DDC were highly motile, continuously crawling through the interstitial space in a Galpha(i protein-coupled receptor-dependent manner. However, within minutes after intradermal delivery of the protozoan parasite Leishmania major, DDC became immobile and incorporated multiple parasites into cytosolic vacuoles. Parasite uptake occurred through the extension of long, highly dynamic pseudopods capable of tracking and engulfing parasites. This was then followed by rapid dendrite retraction towards the cell body. DDC were proficient at discriminating between parasites and inert particles, and parasite uptake was independent of the presence of neutrophils. Together, our study has visualized the dynamics and microenvironmental context of parasite encounter by an innate immune cell subset during the initiation of the immune response. Our results uncover a unique migratory tissue surveillance program of DDC that ensures the rapid detection of pathogens.

  9. 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.

  10. 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.

  11. Impact of MAPK Pathway Activation in BRAFV600 Melanoma on T Cell and Dendritic Cell Function

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    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.

  12. Avoiding horror autotoxicus: The importance of dendritic cells in peripheral T cell tolerance

    Science.gov (United States)

    Steinman, Ralph Marvin; Nussenzweig, Michel C.

    2002-01-01

    The immune system generally avoids horror autotoxicus or autoimmunity, an attack against the body's own constituents. This avoidance requires that self-reactive T cells be actively silenced or tolerized. We propose that dendritic cells (DCs) play a critical role in establishing tolerance, especially in the periphery, after functioning T cells have been produced in the thymus. In the steady state, meaning in the absence of acute infection and inflammation, DCs are in an immature state and not fully differentiated to carry out their known roles as inducers of immunity. Nevertheless, immature DCs continuously circulate through tissues and into lymphoid organs, capturing self antigens as well as innocuous environmental proteins. Recent experiments have provided direct evidence that antigen-loaded immature DCs silence T cells either by deleting them or by expanding regulatory T cells. This capacity of DCs to induce peripheral tolerance can work in two opposing ways in the context of infection. In acute infection, a beneficial effect should occur. The immune system would overcome the risk of developing autoimmunity and chronic inflammation if, before infection, tolerance were induced to innocuous environmental proteins as well as self antigens captured from dying infected cells. For chronic or persistent pathogens, a second but dire potential could take place. Continuous presentation of a pathogen by immature DCs, HIV-1 for example, may lead to tolerance and active evasion of protective immunity. The function of DCs in defining immunologic self provides a new focus for the study of autoimmunity and chronic immune-based diseases. PMID:11773639

  13. Avoiding horror autotoxicus: the importance of dendritic cells in peripheral T cell tolerance.

    Science.gov (United States)

    Steinman, Ralph Marvin; Nussenzweig, Michel C

    2002-01-08

    The immune system generally avoids horror autotoxicus or autoimmunity, an attack against the body's own constituents. This avoidance requires that self-reactive T cells be actively silenced or tolerized. We propose that dendritic cells (DCs) play a critical role in establishing tolerance, especially in the periphery, after functioning T cells have been produced in the thymus. In the steady state, meaning in the absence of acute infection and inflammation, DCs are in an immature state and not fully differentiated to carry out their known roles as inducers of immunity. Nevertheless, immature DCs continuously circulate through tissues and into lymphoid organs, capturing self antigens as well as innocuous environmental proteins. Recent experiments have provided direct evidence that antigen-loaded immature DCs silence T cells either by deleting them or by expanding regulatory T cells. This capacity of DCs to induce peripheral tolerance can work in two opposing ways in the context of infection. In acute infection, a beneficial effect should occur. The immune system would overcome the risk of developing autoimmunity and chronic inflammation if, before infection, tolerance were induced to innocuous environmental proteins as well as self antigens captured from dying infected cells. For chronic or persistent pathogens, a second but dire potential could take place. Continuous presentation of a pathogen by immature DCs, HIV-1 for example, may lead to tolerance and active evasion of protective immunity. The function of DCs in defining immunologic self provides a new focus for the study of autoimmunity and chronic immune-based diseases.

  14. 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.

  15. C-Reactive Protein Impairs Dendritic Cell Development, Maturation, and Function: Implications for Peripheral Tolerance

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    Rachel V. Jimenez

    2018-03-01

    Full Text Available C-reactive protein (CRP is the prototypical acute phase reactant, increasing in blood concentration rapidly and several-fold in response to inflammation. Recent evidence indicates that CRP has an important physiological role even at low, baseline levels, or in the absence of overt inflammation. For example, we have shown that human CRP inhibits the progression of experimental autoimmune encephalomyelitis (EAE in CRP transgenic mice by shifting CD4+ T cells away from the TH1 and toward the TH2 subset. Notably, this action required the inhibitory Fcγ receptor IIB (FcγRIIB, but did not require high levels of human CRP. Herein, we sought to determine if CRP’s influence in EAE might be explained by CRP acting on dendritic cells (DC; antigen presenting cells known to express FcγRIIB. We found that CRP (50 µg/ml reduced the yield of CD11c+ bone marrow-derived DCs (BMDCs and CRP (≥5 μg/ml prevented their full expression of major histocompatibility complex class II and the co-stimulatory molecules CD86 and CD40. CRP also decreased the ability of BMDCs to stimulate antigen-driven proliferation of T cells in vitro. Importantly, if the BMDCs were genetically deficient in mouse FcγRIIB then (i the ability of CRP to alter BMDC surface phenotype and impair T cell proliferation was ablated and (ii CD11c-driven expression of a human FCGR2B transgene rescued the CRP effect. Lastly, the protective influence of CRP in EAE was fully restored in mice with CD11c-driven human FcγRIIB expression. These findings add to the growing evidence that CRP has important biological effects even in the absence of an acute phase response, i.e., CRP acts as a tonic suppressor of the adaptive immune system. The ability of CRP to suppress development, maturation, and function of DCs implicates CRP in the maintenance of peripheral T cell tolerance.

  16. Oxymetazoline modulates proinflammatory cytokines and the T-cell stimulatory capacity of dendritic cells.

    Science.gov (United States)

    Tuettenberg, Andrea; Koelsch, Stephan; Knop, Jürgen; Jonuleit, Helmut

    2007-03-01

    The nasal decongestant oxymetazoline (OMZ) is frequently used in the topical treatment of rhinitis/sinusitis. As proinflammatory cytokines play a critical role in the development and maintenance of local inflammation, the aim of this study was to investigate the influence of OMZ on immune cells in order to diminish the mucosal infiltration of the nose. Peripheral blood mononuclear cells (PBMC) from buffy coats of healthy volunteers were isolated and stimulated in the presence or absence of OMZ. In addition, monocyte-derived dendritic cells (DC) were generated and different concentrations of OMZ were added. DC phenotype and their T-cell stimulatory properties were analysed. The vasoactive substance OMZ showed a concentration dependent inhibitory effect on T-cell activation as well as a dominant effect on T-cell stimulatory properties of DC. Low concentrations of OMZ inhibited the proliferation of polyclonally activated T cells. In addition, secretion of proinflammatory mediators such as the cytokines interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF alpha), IL-6 and IL-8 were inhibited in the presence of physiological doses of OMZ. Interestingly, the addition of IL-6 to DC-T-cell co-culture was able to completely restore T-cell proliferation. In conclusion, these findings indicate that the anti-inflammatory properties of OMZ are partially mediated by the inhibition of proinflammatory cytokines as well as reduced T-cell stimulatory capacity of DC resulting in a repressed stimulation of T cells. Therefore, the therapeutic benefit of OMZ can be explained in part by its immunomodulating effects in the topical treatment of nasal inflammation.

  17. Circulating dendritic cells in pediatric patients with nephrotic syndrome

    African Journals Online (AJOL)

    EL-HAKIM

    immune system in the pathogenesis of idiopathic. NS3. DCs are rare, ubiquitously distributed, migratory antigen presenting cells (APCs), derived from. CD34 bone marrow stem cells. In addition to having the unique capacity to prime naive T cells,. DCs also regulate various effector cell functions and play central roles in ...

  18. 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.

  19. Developmental hypothyroxinaemia and hypothyroidism limit dendritic growth of cerebellar Purkinje cells in rat offspring: involvement of microtubule-associated protein 2 (MAP2) and stathmin.

    Science.gov (United States)

    Wang, Yuan; Wang, Yi; Dong, Jing; Wei, Wei; Song, Binbin; Min, Hui; Teng, Weiping; Chen, Jie

    2014-06-01

    Iodine is essential for the synthesis of thyroid hormone. Iodine deficiency (ID)-induced hypothyroxinaemia and hypothyroidism during developmental period contribute to impairments of function in the brain, such as psychomotor and motor alterations. However, the mechanisms are still unclear. Therefore, the present research is to study the effects of developmental hypothyroxinaemia caused by mild ID and developmental hypothyroidism caused by severe ID or methimazole (MMZ) on dendritic growth in filial cerebellar Purkinje cells (PCs) and the underlying mechanisms. A maternal hypothyroxinaemia model was established in Wistar rats using a mild ID diet, and two maternal hypothyroidism models were developed with either severe ID diet or MMZ water. We examined the total dendritic length using immunofluorescence, and Western blot analysis was conducted to investigate the activity of microtubule-associated protein 2 (MAP2), stathmin and calcium/calmodulin-dependent protein kinase II (CaMKII). Hypothyroxinaemia and hypothyroidism reduced the total dendritic length of cerebellar PCs, decreased MAP2 and its phosphorylation, increased stathmin but reduced its phosphorylation and down-regulated the activity of CaMKII and its phosphorylation in cerebellar PCs on postnatal day (PN) 7, PN14 and PN21. Developmental hypothyroxinaemia induced by mild ID and hypothyroidism induced by severe ID or MMZ limit PCs dendritic growth, which may involve in the disturbance of MAP2 and stathmin in a CaMKII-dependent manner. It suggests a potential mechanism of motor coordination impairments caused by developmental hypothyroxinaemia and hypothyroidism. © 2013 British Neuropathological Society.

  20. Induction of T-cell memory by a dendritic cell vaccine: a computational model.

    Science.gov (United States)

    Pappalardo, Francesco; Pennisi, Marzio; Ricupito, Alessia; Topputo, Francesco; Bellone, Matteo

    2014-07-01

    Although results from phase III clinical trials substantially support the use of prophylactic and therapeutic vaccines against cancer, what has yet to be defined is how many and how frequent boosts are needed to sustain a long-lasting and protecting memory T-cell response against tumor antigens. Common experience is that such preclinical tests require the sacrifice of a relatively large number of animals, and are particularly time- and money-consuming. As a first step to overcome these hurdles, we have developed an ordinary differential equation model that includes all relevant entities (such as activated cytotoxic T lymphocytes and memory T cells), and investigated the induction of immunological memory in the context of wild-type mice injected with a dendritic cell-based vaccine. We have simulated the biological behavior both in the presence and in the absence of memory T cells. Comparing results of ex vivo and in silico experiments, we show that the model is able to envisage the expansion and persistence of antigen-specific memory T cells. The model might be applicable to more complex vaccination schedules and substantially in any biological condition of prime-boosting. The model is fully described in the article. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  1. Functional Specialization of Skin Dendritic Cell Subsets in Regulating T Cell Responses

    Science.gov (United States)

    Clausen, Björn E.; Stoitzner, Patrizia

    2015-01-01

    Dendritic cells (DC) are a heterogeneous family of professional antigen-presenting cells classically recognized as most potent inducers of adaptive immune responses. In this respect, Langerhans cells have long been considered to be prototypic immunogenic DC in the skin. More recently this view has considerably changed. The generation of in vivo cell ablation and lineage tracing models revealed the complexity of the skin DC network and, in particular, established the existence of a number of phenotypically distinct Langerin+ and negative DC populations in the dermis. Moreover, by now we appreciate that DC also exert important regulatory functions and are required for the maintenance of tolerance toward harmless foreign and self-antigens. This review summarizes our current understanding of the skin-resident DC system in the mouse and discusses emerging concepts on the functional specialization of the different skin DC subsets in regulating T cell responses. Special consideration is given to antigen cross-presentation as well as immune reactions toward contact sensitizers, cutaneous pathogens, and tumors. These studies form the basis for the manipulation of the human counterparts of the murine DC subsets to promote immunity or tolerance for the treatment of human disease. PMID:26557117

  2. Rapamycin Conditioning of Dendritic Cells Differentiated from Human ES Cells Promotes a Tolerogenic Phenotype

    Directory of Open Access Journals (Sweden)

    Kathryn M. Silk

    2012-01-01

    Full Text Available While human embryonic stem cells (hESCs may one day facilitate the treatment of degenerative diseases requiring cell replacement therapy, the success of regenerative medicine is predicated on overcoming the rejection of replacement tissues. Given the role played by dendritic cells (DCs in the establishment of immunological tolerance, we have proposed that DC, rendered tolerogenic during their differentiation from hESC, might predispose recipients to accept replacement tissues. As a first step towards this goal, we demonstrate that DC differentiated from H1 hESCs (H1-DCs are particularly responsive to the immunosuppressive agent rapamycin compared to monocyte-derived DC (moDC. While rapamycin had only modest impact on the phenotype and function of moDC, H1-DC failed to upregulate CD40 upon maturation and displayed reduced immunostimulatory capacity. Furthermore, coculture of naïve allogeneic T cells with rapamycin-treated H1-DC promoted an increased appearance of CD25hi Foxp3+ regulatory T cells, compared to moDC. Our findings suggest that conditioning of hESC-derived DC with rapamycin favours a tolerogenic phenotype.

  3. BLASTIC PLASMACYTOID DENDRITIC CELL NEOPLASM --A RAPIDLY EVOLVING ENTITY. CASE REPORT.

    Science.gov (United States)

    Andrese, Elena; Solovăstru, Laura Gheucă; Dimofte, G; Ferariu, D; Porumb, V; Vâţă, D; Iancul, Luminita Smaranda

    2015-01-01

    Blastic plasmacytoid dendritic cell neoplasm (BPDCN), CD4+/CD56+hematodermic neoplasm was formally known as blastic NK-cell lymphoma. It is in fact a form of acute myeloid leukemia notable for highly aggressive behavior with cutaneous, lymph node and bone marrow involvement. This entity is derived from plasmocytoid dendritic cells and has a predilection for extranodal sites, especially the skin. Elderly male patients are the most affected and the prognostic is poor. The first case was reported in 1994 and sice then, single cases and a few small series have been published. This article presents the case of a previously healthy 56-years-old man, who presented himself to a skin eruption consisting in multiple, large dermal ulcerated tumors, located on the trunk and scalp. The lesions were painless and grew in size rapidly. Physical examination was normal except for the skin lesions. Histological examination of a biopsy specimen and immunohistochemical studies (positive for next markers: CD4, CD 45, CD56, CD68, Ki 67) revealed the rare diagnostic-blastic plasmacytoid dendritic cell neoplasm.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-05-20

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

  5. Dendritic Cell-Mediated T Cell Proliferation -A Functional Bioindicator of Inflammatory Source-Specific Particulate Matter

    Science.gov (United States)

    Previously we found that dendritic cells (DC) were sensitive functional bioindicators of ambient PM (APM) exposure mediating Th2-allergic inflammation in the draining lymph nodes. Here, the ability of bone-marrow-derived DC (DC) and putative BM-derived basophils (Ba) to present a...

  6. DC-SIGN-mediated infectious synapse formation enhances X4 HIV-1 transmission from dendritic cells to T cells

    NARCIS (Netherlands)

    Arrighi, Jean-François; Pion, Marjorie; Garcia, Eduardo; Escola, Jean-Michel; van Kooyk, Yvette; Geijtenbeek, Teunis B.; Piguet, Vincent

    2004-01-01

    Dendritic cells (DCs) are essential for the early events of human immunodeficiency virus (HIV) infection. Model systems of HIV sexual transmission have shown that DCs expressing the DC-specific C-type lectin DC-SIGN capture and internalize HIV at mucosal surfaces and efficiently transfer HIV to CD4+

  7. 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

    Commensal gut bacteria have potent effects on the immune system, which are partially mediated by intestinal dendritic cells (DC). Distinct commensals confer different properties to in vitro-generated DC. The aim of the present study was to reveal strain-dependent maturation patterns in primary DC....... To this end, we compared the response of mouse Peyer's patch (PP) DC, mesenteric lymph node (MLN) DC and spleen DC to the commensal bacteria, Bifidobacterium longum Q46, Lactobacillus acidophilus X37 and Escherichia coli Nissle 1917. Bacterial maturation of DC occurred independently of tissue origin....... 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...

  8. Primary nasopharyngeal interdigitating dendritic cell tumor presentation and response to radiation therapy

    Directory of Open Access Journals (Sweden)

    Paul W. Read

    2010-03-01

    Full Text Available We report the case of a primary nasopharyngeal interdigitating dendritic cell tumor (IDDCT. A 25-year old male presented with bilateral decreased hearing, double vision, and ataxia. Flexible nasopharyngoscopy reviewed a large mass obstructing and filling the entire nasopharynx. MRI and PET-CT confirmed the presence of the primary tumor and demonstrated bilateral cervical lymphadenopathy. Biopsy of the nasopharynx revealed a hematolymphoid neoplasm with dendritic cell differentiation, most consistent with an IDDCT. The lesion was unresectable. The patient was treated with definitive radiotherapy to 66 Gy to the primary tumor and 50 Gy to the bilateral cervical lymphatics using an IMRT technique. A complete response was achieved and the patient remains disease free at the primary site 23 months after completion of radiotherapy.

  9. 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...... IL-20 effects on DC maturation, receptor expression and signaling. By use of extra cellular matrix components mimicking the skin environment, we also studied the functional effects of IL-20 on the chemotactic migration of DCs. Based on the recent finding that CD18 integrin are shed during migration...

  10. 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

  11. 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

  12. [Human soluble dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin inhibits phagocytosis of Staphylococcus aureus by immature dendritic cells].

    Science.gov (United States)

    Li, Hui-Jie; Xu, Tian-Yu; Zhou, Jia; Zhu, Ling-Yan; Zhang, Li-Yun; Lu, Xiao; Chen, Zheng-Liang

    2015-04-01

    To study the effect and mechanism of soluble dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin (sDC-SIGN) on the phagocytosis of Staphylococcus aureus (S. aureus) by immature dendritic cells (imDCs). Flow cytometry was employed to examine the effect of sDC-SIGN on the phagocytosis of S. aureus by imDCs. Enzyme-linked immunosorbent assay (ELISA) was used to analyze the binging of sDC-SIGN to S. aureus, lipoteichoic acid (LTA) and lipopolysaccharides (LPS) and investigate the effect of the ligands mannan and LTA and anti-DC-SIGN antibodies 1C6 and 4H3 on the binging of sDC-SIGN to S. aureus. sDC-SIGN inhibited the phagocytosis of S. aureus by imDCs. sDC-SIGN bound to S. aureus in a Ca(2+)-dependent manner. sDC-SIGN concentration-dependently bound to LTA, but not to LTA, and the binging of sDC-SIGN to S. aureus was blocked by mannan, LTA, 1C6 and 4H3. sDC-SIGN preferentially binds to the carbohydrate constituents on S. aureus to affect the binding between membrane-bound DC-SIGN and S. aureus, thus suppressing the phagocytosis of S. aureus by imDCs.

  13. Changes in human dendritic cell number and function in severe obesity may contribute to increased susceptibility to viral infection.

    LENUS (Irish Health Repository)

    O'Shea, D

    2013-02-26

    Dendritic cells (DCs) are key immune sentinels linking the innate and adaptive immune systems. DCs recognise danger signals and initiate T-cell tolerance, memory and polarisation. They are critical cells in responding to a viral illness. Obese individuals have been shown to have an impaired response to vaccinations against virally mediated conditions and to have an increased susceptibility to multi-organ failure in response to viral illness. We investigated if DCs are altered in an obese cohort (mean body mass index 51.7±7.3 kg m(-2)), ultimately resulting in differential T-cell responses. Circulating DCs were found to be significantly decreased in the obese compared with the lean cohort (0.82% vs 2.53%). Following Toll-like receptor stimulation, compared with lean controls, DCs generated from the obese cohort upregulated significantly less CD83 (40% vs 17% mean fluorescence intensity), a molecule implicated in the elicitation of T-cell responses, particularly viral responses. Obese DCs produced twofold more of the immunosuppressive cytokine interleukin (IL)-10 than lean controls, and in turn stimulated fourfold more IL-4-production from allogenic naive T cells. We conclude that obesity negatively impacts the ability of DCs to mature and elicit appropriate T-cell responses to a general stimulus. This may contribute to the increased susceptibility to viral infection observed in severe obesity.International Journal of Obesity advance online publication, 26 February 2013; doi:10.1038\\/ijo.2013.16.

  14. 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.

  15. Deletion of BCG Hip1 protease enhances dendritic cell and CD4 T cell responses.

    Science.gov (United States)

    Bizzell, Erica; Sia, Jonathan Kevin; Quezada, Melanie; Enriquez, Ana; Georgieva, Maria; Rengarajan, Jyothi

    2017-12-28

    Dendritic cells (DCs) play a key role in the generation of CD4 T cell responses to pathogens. Mycobacterium tuberculosis (Mtb) harbors immune evasion mechanisms that impair DC responses and prevent optimal CD4 T cell immunity. The vaccine strain Mycobacterium bovis Bacille Calmette-Guérin (BCG) shares many of the immune evasion proteins utilized by Mtb, but the role of these proteins in DC and T cell responses elicited by BCG is poorly understood. We previously reported that the Mtb serine protease, Hip1, promotes sub-optimal DC responses during infection. Here, we tested the hypothesis that BCG Hip1 modulates DC functions and prevents optimal antigen-specific CD4 T cell responses that limit the immunogenicity of BCG. We generated a strain of BCG lacking hip1 (BCGΔhip1) and show that it has superior capacity to induce DC maturation and cytokine production compared with the parental BCG. Furthermore, BCGΔhip1-infected DCs were more effective at driving the production of IFN-γ and IL-17 from antigen-specific CD4 T cells in vitro. Mucosal transfer of BCGΔhip1-infected DCs into mouse lungs induced robust CD4 T cell activation in vivo and generated antigen-specific polyfunctional CD4 T cell responses in the lungs. Importantly, BCGΔhip1-infected DCs enhanced control of pulmonary bacterial burden following Mtb aerosol challenge compared with the transfer of BCG-infected DCs. These results reveal that BCG employs Hip1 to impair DC activation, leading to attenuated lung CD4 T cell responses with limited capacity to control Mtb burden after challenge. ©2017 Society for Leukocyte Biology.

  16. 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.

  17. Propagating dendritic action potential mediates synaptic transmission in CA1 pyramidal cells in situ.

    Science.gov (United States)

    Herreras, O

    1990-11-01

    1. The events leading to the Schaffer collateral-induced discharge of CA1 pyramidal neurons were investigated in the hippocampus of anesthetized rats by current source-density (CSD) analysis. 2. The earliest evoked currents detected shortly after a stimulus were a sink in the zone where synapses are known to be located (300-350 microns ventral to the somatic layer) flanked by two smaller sources in the distal portion of the apical dendrites and in the somatic layer. This synaptic sink (SyS) extended over 75-100 microns; it lasted for 15-20 ms, and it reached its maximum amplitude some milliseconds after the population spike (PS) and remained in the same location. Stimuli submaximal and supramaximal for evoking a PS yielded the same pattern of current distribution for the SyS. Presynaptic fiber volleys were not detected in these recordings. 3. During the rising phase of the SyS a second sink appeared in a more proximal portion of the apical dendrites. This late dendritic sink (LS) extended over 50-75 microns and was centered 100-150 microns ventral to the somatic layer. This proximal dendritic sink was of amplitude comparable with the SyS; it outlasted the latter and was not necessarily followed by a somatic PS. The LS was extinguished with the appearance of a PS, whereas the SyS persisted regardless of the presence of a PS. 4. After maximal stimuli the LS grew until it exceeded a threshold amplitude, and then, it started to move somatopetally as a continuously propagating sink (PrS). The average speed of propagation was approximately 0.2 m/s. In 0.5-0.7 ms the PrS reached the cell-body layer displacing the passive source that moved into the basal dendrites. The PrS then became the intensive sink corresponding to the main (negative) phase of the somatic PS. This was followed by the development of an active source in the soma layer, probably corresponding to the repolarization phase of the PS. 5. From these observations it appears that the LS and PrS are active

  18. Melanopsin ganglion cells extend dendrites into the outer retina during early postnatal development.

    Science.gov (United States)

    Renna, Jordan M; Chellappa, Deepa K; Ross, Christopher L; Stabio, Maureen E; Berson, David M

    2015-09-01

    Melanopsin ganglion cells express the photopigment melanopsin and are the first functional photoreceptors to develop in the mammalian retina. They have been shown to play a variety of important roles in visual development and behavior in the early postnatal period (Johnson et al., 2010; Kirkby and Feller, 2013; Rao et al., 2013; Renna et al., 2011). Here, we probed the maturation of the dendritic arbors of melanopsin ganglion cells during this developmental period in mice. We found that some melanopsin ganglion cells (mainly the M1-subtype) transiently extend their dendrites not only into the inner plexiform layer (where they receive synaptic inputs from bipolar and amacrine cells) but also into the outer plexiform layer, where in mature retina, rod and cone photoreceptors are thought to contact only bipolar and horizontal cells. Thus, some immature melanopsin ganglion cells are biplexiform. This feature is much less common although still present in the mature retina. It reaches peak incidence 8-12 days after birth, before the eyes open and bipolar cells are sufficiently mature to link rods and cones to ganglion cells. At this age, some outer dendrites of melanopsin ganglion cells lie in close apposition to the axon terminals of cone photoreceptors and express a postsynaptic marker of glutamatergic transmission, postsynaptic density-95 protein (PSD-95). These findings raise the possibility of direct, monosynaptic connections between cones and melanopsin ganglion cells in the early postnatal retina. We provide a detailed description of the developmental profile of these processes and consider their possible functional and evolutionary significance. © 2015 Wiley Periodicals, Inc.

  19. 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

  20. 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 : HPV 16 * minimal residual tumour disease * dendritic cells Subject RIV: EC - Immunology Impact factor: 3.056, year: 2004

  1. 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

  2. Make immunological peace not war: Potential applications of tolerogenic dendritic cells.

    Science.gov (United States)

    Walton, Emma Louise

    2017-04-01

    In this issue of the Biomedical Journal, we explore the powerful immunosuppressive properties of tolerogenic dendritic cells and discuss their potential to bring about lifelong tolerance in transplantation and autoimmune disease. We also highlight an exciting new development in the field of malaria diagnosis that could facilitate early detection of the disease. Copyright © 2017 Chang Gung University. Published by Elsevier B.V. All rights reserved.

  3. Dendritic Cells and Their Role in Cardiovascular Diseases: A View on Human Studies

    OpenAIRE

    Maja-Theresa Dieterlen; Katja John; Hermann Reichenspurner; Friedrich W. Mohr; Markus J. Barten

    2016-01-01

    The antigen-presenting dendritic cells (DCs) are key to the immunological response, with different functions ascribed ranging from cellular immune activation to induction of tolerance. Such immunological responses are involved in the pathophysiological mechanisms of cardiovascular diseases, with DCs shown to play a role in atherosclerosis, hypertension, and heart failure and most notably following heart transplantation. A better understanding of the interplay between the immune system and car...

  4. 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...... difference at the level of miRNA induction between these two groups was observed, suggesting that quantitative evaluation of selected miRNAs potentially can predict the immunogenicity of DC vaccines....

  5. Feeding dendritic cells with tumor antigens: self-service buffet or à la carte?

    OpenAIRE

    Melero, I. (Ignacio); Vile, R.G. (Richard G.); Colombo, M.P. (Mario P.)

    2000-01-01

    Adoptive transfer of autologous dendritic cells (DC) presenting tumor-associated antigens initiate and sustain an immune response which eradicate murine malignancies. Based on these observations, several clinical trials are in progress testing safety and efficacy with encouraging preliminary reports. In these approaches, ex vivo incubation of DC with a source of tumor antigens is required to load the relevant antigenic epitopes on the adequate antigen presenting molecules. Recent data show th...

  6. Ribosomal protein mRNAs are translationally-regulated during human dendritic cells activation by LPS.

    OpenAIRE

    Ceppi, Maurizio; Clavarino, Giovanna; Gatti, Evelina; Schmidt, Enrico; De Gassart, Aude; Blankenship, Derek; Ogola, Gerald; Banchereau, Jacques; Chaussabel, Damien; Pierre, Philippe

    2009-01-01

    International audience; BACKGROUND: Dendritic cells (DCs) are the sentinels of the mammalian immune system, characterized by a complex maturation process driven by pathogen detection. Although multiple studies have described the analysis of activated DCs by transcriptional profiling, recent findings indicate that mRNAs are also regulated at the translational level. A systematic analysis of the mRNAs being translationally regulated at various stages of DC activation was performed using transla...

  7. Modification of dendritic development.

    Science.gov (United States)

    Feria-Velasco, Alfredo; del Angel, Alma Rosa; Gonzalez-Burgos, Ignacio

    2002-01-01

    Since 1890 Ramón y Cajal strongly defended the theory that dendrites and their processes and spines had a function of not just nutrient transport to the cell body, but they had an important conductive role in neural impulse transmission. He extensively discussed and supported this theory in the Volume 1 of his extraordinary book Textura del Sistema Nervioso del Hombre y de los Vertebrados. Also, Don Santiago significantly contributed to a detailed description of the various neural components of the hippocampus and cerebral cortex during development. Extensive investigation has been done in the last Century related to the functional role of these complex brain regions, and their association with learning, memory and some limbic functions. Likewise, the organization and expression of neuropsychological qualities such as memory, exploratory behavior and spatial orientation, among others, depend on the integrity and adequate functional activity of the cerebral cortex and hippocampus. It is known that brain serotonin synthesis and release depend directly and proportionally on the availability of its precursor, tryptophan (TRY). By using a chronic TRY restriction model in rats, we studied their place learning ability in correlation with the dendritic spine density of pyramidal neurons in field CA1 of the hippocampus during postnatal development. We have also reported alterations in the maturation pattern of the ability for spontaneous alternation and task performance evaluating short-term memory, as well as adverse effects on the density of dendritic spines of hippocampal CA1 field pyramidal neurons and on the dendritic arborization and the number of dendritic spines of pyramidal neurons from the third layer of the prefrontal cortex using the same model of TRY restriction. The findings obtained in these studies employing a modified Golgi method, can be interpreted as a trans-synaptic plastic response due to understimulation of serotoninergic receptors located in the

  8. Dendritic cells from oral cavity induce Foxp3(+ regulatory T cells upon antigen stimulation.

    Directory of Open Access Journals (Sweden)

    Sayuri Yamazaki

    Full Text Available Evidence is accumulating that dendritic cells (DCs from the intestines have the capacity to induce Foxp3(+CD4(+ regulatory T cells (T-regs and regulate immunity versus tolerance in the intestines. However, the contribution of DCs to controlling immunity versus tolerance in the oral cavity has not been addressed. Here, we report that DCs from the oral cavity induce Foxp3(+ T-regs as well as DCs from intestine. We found that oral-cavity-draining cervical lymph nodes contained higher frequencies of Foxp3(+ T-regs and ROR-γt(+ CD4(+T cells than other lymph nodes. The high frequency of Foxp3(+ T-regs in the oral-cavity-draining cervical lymph nodes was not dependent on the Toll like receptor (TLR adaptor molecules, Myd88 and TICAM-1 (TRIF. In contrast, the high frequency of ROR-γt(+ CD4(+T cells relies on Myd88 and TICAM-1. In vitro data showed that CD11c(+ DCs from oral-cavity-draining cervical lymph nodes have the capacity to induce Foxp3(+ T-regs in the presence of antigen. These data suggest that, as well as in the intestinal environment, antigen-presenting DCs may play a vital role in maintaining tolerance by inducing Foxp3(+ T-regs in the oral cavity.

  9. 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.

  10. 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

  11. Immunotherapy of hormone-refractory prostate cancer with antigen-loaded dendritic cells.

    Science.gov (United States)

    Small, E J; Fratesi, P; Reese, D M; Strang, G; Laus, R; Peshwa, M V; Valone, F H

    2000-12-01

    Provenge (Dendreon Corp, Seattle, WA) is an immunotherapy product consisting of autologous dendritic cells loaded ex vivo with a recombinant fusion protein consisting of prostatic acid phosphatase (PAP) linked to granulocyte-macrophage colony-stimulating factor. Sequential phase I and phase II trials were performed to determine the safety and efficacy of Provenge and to assess its capacity to break immune tolerance to the normal tissue antigen PAP. All patients had hormone-refractory prostate cancer. Dendritic-cell precursors were harvested by leukapheresis in weeks 0, 4, 8, and 24, loaded ex vivo with antigen for 2 days, and then infused intravenously over 30 minutes. Phase I patients received increasing doses of Provenge, and phase II patients received all the Provenge that could be prepared from a leukapheresis product. Patients tolerated treatment well. Fever, the most common adverse event, occurred after 15 infusions (14.7%). All patients developed immune responses to the recombinant fusion protein used to prepare Provenge, and 38% developed immune responses to PAP. Three patients had a more than 50% decline in prostate-specific antigen (PSA) level, and another three patients had 25% to 49% decreases in PSA. The time to disease progression correlated with development of an immune response to PAP and with the dose of dendritic cells received. Provenge is a novel immunotherapy agent that is safe and breaks tolerance to the tissue antigen PAP. Preliminary evidence for clinical efficacy warrants further exploration.

  12. Immune responses of dendritic cells after acquiring antigen from apoptotic hepatocholangioma cells caused by γ-ray

    International Nuclear Information System (INIS)

    Wu Gang; Gu Hongguang; Han Benli; Pei Xuetao

    2002-01-01

    Objective: To investigate the induction of cytotoxic T lymphocytes (CTLs) in antitumor responsiveness and therapeutic effects after dendritic cells (DCs) acquired antigen from apoptotic hepatocholangioma cells. Methods: DCs from blood mononuclear cells that maintain the characteristics of immaturity-anti-gen-capturing and-processing capacity were established in vitro by using granulocyte/macrophage colony-stimulating factor (GM-CSF) and interleukin-4. Then, apoptosis in hepatocholangioma cells was induced with γ-radiation. The experimental groups included (1) co-culture of DCs, and apoptotic cancer cells and T cells; (2) co-culture of DCs necrotic cancer cells and T cells; (3) co-culture of DCs-cultured cancer cell and T cells. These cells were co-cultured for 7 days. DCs and T cell were enriched separately. Finally, antitumor response test was carried out. Results: These cells had typical dendritic morphology, expressed high levels of CD1a, B7 and acquired antigen from apoptotic cells caused by γ-rays and induced an increased T cell-stimulatory capacity in MLR. Conclusions: DCs obtained from blood mononuclear cells using GM-CSF and IL-4 and DCs can efficiently present antigen driven from apoptotic cells caused by γ-rays and induce T cells increasing obviously. It can probably become an effective approach of DC transduction with antigen

  13. CD207+/langerin positive dendritic cells in invasive and in situ cutaneous malignant melanoma

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    Grzegorz Dyduch

    2017-05-01

    Full Text Available Introduction : Dendritic cells are crucial for cutaneous immune response. Their role in melanoma progression is however a matter of controversy. Material and methods : The number of dendritic cells within epidermis and in peri- and intratumoral location was analyzed using CD207 immunostain in 17 cases of in situ and 25 case of invasive melanoma. Results : Average peritumoral CD207+ cells count was 22.88 for all cases, 17.94 for in situ lesions and 26.24 for invasive cases. Average epidermal CD207+ cells count was 164.47 for all cases, 183.00 for in situ lesions and 150.78 – for invasive cases. In case of invasive melanomas, peritumoral CD207+ cells count was positively correlated with Breslow stage (R = 0.59 mitotic activity within the tumor (R = 0.62. Invasive cases with regression showed higher intratumoral and epidermal CD207+ cells count than the ones without (275.00 vs. 95.32 and 173.20 vs. 148.35 but lower peritumoral CD207+ cells count (17.60 vs. 27.26. Invasive cases with ulceration showed higher intratumoral and peritumoral CD207+ cells count than the ones without ulceration (220.08 vs. 55.67 and 44.17 vs. 9.69. Conclusions : CD207+ cells play a role in both progression and regression of melanoma but their exact role needs further studies.

  14. Specific targeting of whole lymphoma cells to dendritic cells ex vivo provides a potent antitumor vaccine

    Directory of Open Access Journals (Sweden)

    Mocikat Ralph

    2007-03-01

    Full Text Available Abstract Background Dendritic cells (DC pulsed with tumor-derived antigenic material have widely been used in antitumor vaccination protocols. However, the optimal strategy of DC loading has not yet been established. Our aim was to define requirements of optimal DC vaccines in terms of in vivo protection in a murine B-cell lymphoma model. Methods We compare various loading reagents including whole parental and modified tumor cells and a single tumor-specific antigen, namely the lymphoma idiotype (Id. Bone marrow-derived DC were pulsed in vitro and used for therapy of established A20 lymphomas. Results We show that a vaccine with superior antitumor efficacy can be generated when DC are loaded with whole modified tumor cells which provide both (i antigenic polyvalency and (ii receptor-mediated antigen internalization. Uptake of cellular material was greatly enhanced when the tumor cells used for DC pulsing were engineered to express an anti-Fc receptor immunoglobulin specificity. Upon transfer of these DC, established tumor burdens were eradicated in 50% of mice. By contrast, pulsing DC with unmodified lymphoma cells or with the lymphoma Id, even when it was endowed with the anti-Fc receptor binding arm, was far less effective. A specific humoral anti-Id response could be detected, particularly following delivery of Id protein-pulsed DC, but it was not predictive of tumor protection. Instead a T-cell response was pivotal for successful tumor protection. Interaction of the transferred DC with CD8+ T lymphocytes seemed to play a role for induction of the immune response but was dispensable when DC had received an additional maturation stimulus. Conclusion Our analyses show that the advantages of specific antigen redirection and antigenic polyvalency can be combined to generate DC-based vaccines with superior antitumor efficacy. This mouse model may provide information for the standardization of DC-based vaccination protocols.

  15. Chemokine-mediated distribution of dendritic cell subsets in renal cell carcinoma

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    Meyer Werner

    2010-10-01

    Full Text Available Abstract Background Renal cell carcinoma (RCC represents one of the most immunoresponsive cancers. Antigen-specific vaccination with dendritic cells (DCs in patients with metastatic RCC has been shown to induce cytotoxic T-cell responses associated with objective clinical responses. Thus, clinical trials utilizing DCs for immunotherapy of advanced RCCs appear to be promising; however, detailed analyses concerning the distribution and function of DC subsets in RCCs are lacking. Methods We characterized the distribution of the different immature and mature myeloid DC subsets in RCC tumour tissue and the corresponding normal kidney tissues. In further analyses, the expression of various chemokines and chemokine receptors controlling the migration of DC subsets was investigated. Results The highest numbers of immature CD1a+ DCs were found within RCC tumour tissue. In contrast, the accumulation of mature CD83+/DC-LAMP+ DCs were restricted to the invasive margin of the RCCs. The mature DCs formed clusters with proliferating T-cells. Furthermore, a close association was observed between MIP-3α-producing tumour cells and immature CCR6+ DC recruitment to the tumour bed. Conversely, MIP-3β and SLC expression was only detected at the tumour border, where CCR7-expressing T-cells and mature DCs formed clusters. Conclusion Increased numbers of immature DCs were observed within the tumour tissue of RCCs, whereas mature DCs were found in increased numbers at the tumour margin. Our results strongly implicate that the distribution of DC subsets is controlled by local lymphoid chemokine expression. Thus, increased expression of MIP-3α favours recruitment of immature DCs to the tumour bed, whereas de novo local expression of SLC and MIP-3β induces accumulation of mature DCs at the tumour margin forming clusters with proliferating T-cells reflecting a local anti-tumour immune response.

  16. Gal-3 regulates the capacity of dendritic cells to promote NKT-cell-induced liver injury.

    Science.gov (United States)

    Volarevic, Vladislav; Markovic, Bojana Simovic; Bojic, Sanja; Stojanovic, Maja; Nilsson, Ulf; Leffler, Hakon; Besra, Gurdyal S; Arsenijevic, Nebojsa; Paunovic, Verica; Trajkovic, Vladimir; Lukic, Miodrag L

    2015-02-01

    Galectin-3 (Gal-3), an endogenous lectin, exhibits pro- and anti-inflammatory effects in various disease conditions. In order to explore the role of Gal-3 in NKT-cell-dependent pathology, we induced hepatitis in C57BL/6 WT and Gal-3-deficient mice by using specific ligand for NKT cells: α-galactosylceramide, glycolipid Ag presented by CD1d. The injection of α-galactosylceramide significantly enhanced expression of Gal-3 in liver NKT and dendritic cells (DCs). Genetic deletion or selective inhibition of Gal-3 (induced by Gal-3-inhibitor TD139) abrogated the susceptibility to NKT-cell-dependent hepatitis. Blood levels of pro-inflammatory cytokines (TNF-α, IFN-γ, IL-12) and their production by liver DCs and NKT cells were also downregulated. Genetic deletion or selective inhibition of Gal-3 alleviated influx of inflammatory CD11c(+) CD11b(+) DCs in the liver and favored tolerogenic phenotype and IL-10 production of liver NKT and DCs. Deletion of Gal-3 attenuated the capacity of DCs to support liver damage in the passive transfer experiments and to produce pro-inflammatory cytokines in vitro. Gal-3-deficient DCs failed to optimally stimulate production of pro-inflammatory cytokines in NKT cells, in vitro and in vivo. In conclusion, Gal-3 regulates the capacity of DCs to support NKT-cell-mediated liver injury, playing an important pro-inflammatory role in acute liver injury. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Construction and evaluation of rats' tolerogenic dendritic cells (DC ...

    African Journals Online (AJOL)

    Compared with control group and LPS-stimulation group, the less mature adhered cells and hairlike DC were observed in NF-κB decoy group. Significant reduction (p<0.05) was observed for the positive expression and extension of CD80 and CD86 in cell surface. After loaded with calf type II collagen, the low expression of ...

  18. Role for Mechanotransduction in Macrophage and Dendritic Cell Immunobiology

    NARCIS (Netherlands)

    Mennens, S.F.B.J.; Dries, K. van den; Cambi, A.

    2017-01-01

    Tissue homeostasis is not only controlled by biochemical signals but also through mechanical forces that act on cells. Yet, while it has long been known that biochemical signals have profound effects on cell biology, the importance of mechanical forces has only been recognized much more recently.

  19. Immune modulation by dendritic-cell-based cancer vaccines

    Indian Academy of Sciences (India)

    2017-01-31

    Jan 31, 2017 ... The interplay between host immunity and tumour cells has opened the possibility of targeting tumour cells by modulation of the human immune system. Cancer immunotherapy involves the treatment of a tumour by utilizing the recombinant human immune system components to target the pro-tumour ...

  20. Immune modulation by dendritic-cell-based cancer vaccines

    Indian Academy of Sciences (India)

    The interplay between host immunity and tumour cells has opened the possibility of targeting tumour cells bymodulation of the human immune system. Cancer immunotherapy involves the treatment of a tumour by utilizing therecombinant human immune system components to target the pro-tumour microenvironment or by ...

  1. Dendritic cell populations in patients with self-reported food hypersensitivity

    Directory of Open Access Journals (Sweden)

    Lied GA

    2011-05-01

    Full Text Available Gülen A Lied1,3,4,*, Petra Vogelsang2,*, Arnold Berstad1,4, Silke Appel2 1Institute of Medicine, 2Broegelmann Research Laboratory, The Gade Institute, University of Bergen, Norway; 3Division of Gastroenterology, Department of Medicine; 4Section of Clinical Allergology, Department of Occupational Medicine, Haukeland University Hospital, Bergen, Norway *These authors contributed equally to this workAbstract: Self-reported hypersensitivity to food is a common condition and many of these patients have indications of intestinal immune activation. Dendritic cells (DCs are recognized as the most potent antigen-presenting cells involved in both initiating immune responses and maintaining tolerance. The aims of this study were to evaluate the DC populations with their phenotype and T cell stimulatory capacity in patients with food hypersensitivity and to study its relationship with atopic disease. Blood samples from 10 patients with self-reported food hypersensitivity, divided into atopic and nonatopic subgroups, and 10 gender- and age-matched healthy controls were analyzed by flow cytometry using the Miltenyi Blood Dendritic cells kit. Monocyte-derived DCs (moDCs were evaluated concerning their phenotype and T cell stimulatory capacity. DC populations and cell surface markers were not significantly different between patients and healthy controls, but moDCs from atopic patients expressed significantly more CD38 compared to moDCs from nonatopic patients. Moreover, lipopolysaccharide stimulated moDCs from atopic patients produced significantly more interleukin-10 compared to nonatopic patients. CD38 expression was correlated to total serum immunoglobulin E levels. These findings support the notion of immune activation in some patients with self-reported food hypersensitivity. They need to be confirmed in a larger cohort.Keywords: food hypersensitivity, atopy, dendritic cells, CD38

  2. Aging Impairs the Ability of Conventional Dendritic Cells to Cross-Prime CD8+ T Cells upon Stimulation with a TLR7 Ligand.

    Directory of Open Access Journals (Sweden)

    Estefanía R Zacca

    Full Text Available The aging process is accompanied by altered immune system functioning and an increased risk of infection. Dendritic cells (DCs are antigen-presenting cells that play a key role in both adaptive and innate immunity, but how aging affects DCs and their influence on immunity has not been thoroughly established. Here we examined the function of conventional DCs (cDCs in old mice after TLR7 stimulation, focusing on their ability to cross-prime CD8+ T cells. Using polyU, a synthetic ssRNA analog, as TLR7 ligand and OVA as an antigen (Ag model, we found that cDCs from old mice have a poor ability to stimulate a CD8+ T cell-mediated cytotoxic response. cDCs from old mice exhibit alterations in Ag-processing machinery and TLR7 activation. Remarkably, CD8α+ cDCs from old mice have an impaired ability to activate naïve CD8+ T cells and, moreover, a lower capacity to mature and to process exogenous Ag. Taken together, our results suggest that immunosenescence impacts cDC function, affecting the activation of naïve CD8+ T cells and the generation of effector cytotoxic T cells.

  3. Aging Impairs the Ability of Conventional Dendritic Cells to Cross-Prime CD8+ T Cells upon Stimulation with a TLR7 Ligand.

    Science.gov (United States)

    Zacca, Estefanía R; Crespo, María I; Acland, Rachel P; Roselli, Emiliano; Núñez, Nicolás G; Maccioni, Mariana; Maletto, Belkys A; Pistoresi-Palencia, María C; Morón, Gabriel

    2015-01-01

    The aging process is accompanied by altered immune system functioning and an increased risk of infection. Dendritic cells (DCs) are antigen-presenting cells that play a key role in both adaptive and innate immunity, but how aging affects DCs and their influence on immunity has not been thoroughly established. Here we examined the function of conventional DCs (cDCs) in old mice after TLR7 stimulation, focusing on their ability to cross-prime CD8+ T cells. Using polyU, a synthetic ssRNA analog, as TLR7 ligand and OVA as an antigen (Ag) model, we found that cDCs from old mice have a poor ability to stimulate a CD8+ T cell-mediated cytotoxic response. cDCs from old mice exhibit alterations in Ag-processing machinery and TLR7 activation. Remarkably, CD8α+ cDCs from old mice have an impaired ability to activate naïve CD8+ T cells and, moreover, a lower capacity to mature and to process exogenous Ag. Taken together, our results suggest that immunosenescence impacts cDC function, affecting the activation of naïve CD8+ T cells and the generation of effector cytotoxic T cells.

  4. An improved ontological representation of dendritic cells as a paradigm for all cell types

    Directory of Open Access Journals (Sweden)

    Mungall Chris

    2009-02-01

    Full Text Available Abstract Background Recent increases in the volume and diversity of life science data and information and an increasing emphasis on data sharing and interoperability have resulted in the creation of a large number of biological ontologies, including the Cell Ontology (CL, designed to provide a standardized representation of cell types for data annotation. Ontologies have been shown to have significant benefits for computational analyses of large data sets and for automated reasoning applications, leading to organized attempts to improve the structure and formal rigor of ontologies to better support computation. Currently, the CL employs multiple is_a relations, defining cell types in terms of histological, functional, and lineage properties, and the majority of definitions are written with sufficient generality to hold across multiple species. This approach limits the CL's utility for computation and for cross-species data integration. Results To enhance the CL's utility for computational analyses, we developed a method for the ontological representation of cells and applied this method to develop a dendritic cell ontology (DC-CL. DC-CL subtypes are delineated on the basis of surface protein expression, systematically including both species-general and species-specific types and optimizing DC-CL for the analysis of flow cytometry data. We avoid multiple uses of is_a by linking DC-CL terms to terms in other ontologies via additional, formally defined relations such as has_function. Conclusion This approach brings benefits in the form of increased accuracy, support for reasoning, and interoperability with other ontology resources. Accordingly, we propose our method as a general strategy for the ontological representation of cells. DC-CL is available from http://www.obofoundry.org.

  5. The immune modulation of Clara cell-10 in human peripheral monocytes and dendritic cells.

    Science.gov (United States)

    Yoon, Jung Min; Lee, Kyu-Hwa; Lee, Sang Min; Lim, Jae-Jun; Yang, Seok-Chul; Yoo, Chul-Gyu; Lee, Choon-Taek; Han, Sung Koo; Shim, Young-Soo; Kim, Young Whan

    2010-09-01

    Although Clara cell secretory protein (CC-10, CC-16 or uteroglobin, secretoglobin 1A1) has been ascribed anti-inflammatory, immunomodulatory and anti-cancer activity roles in lung diseases including lung cancer, its precise function remains unclear. The objective of the present study was to evaluate the role of CC-10 in the immunomodulation of human monocytes and dendritic cells (DCs). The human lung adenocarcinoma cell line A549, was used to examine PGE2 production after cyclooxygenase (COX) inhibition and adenovirus encoding human CC-10 cDNA (Ad-CC-10) transfection. Type I and II cytokines were measured from peripheral blood mononuclear cells (PBMCs) and DCs which were cultured with tumor supernatant (TSN) or Ad-CC-10 transfected TSN. When PBMCs were cultured with supernatant A549 (tumor supernatant, TSN), the levels of T-cell helper type 1 (Th1) and 2 (Th2) cytokines increased. However, CC-10 inhibited the induction of Th2 cytokines of PBMCs stimulated with TSN. In DCs, TSN inhibited Th1 type cytokines but induced Th2 type. In contrast, TSN treated with either CC-10 or NS398 (COX-2 inhibitor) stimulated Th1 type and inhibited Th2 type without any phenotypic changes. The supernatants generated in the presence of NS-398 or CC-10 prevented tumor-induced inhibition of allogeneic T-cell stimulation. While the level of interleukin (IL)-10 secretion from DC-Ad-CC-10 was decreased, the level of IL-12 secretion was increased by CC-10. Collectively our data suggest that a supernatant of NSCLC causes an imbalance in the immune response of PBMCs and DCs, which is reversed by CC-10. This suggests that CC-10 is a candidate for the development of a new immunotherapy for lung cancer.

  6. Autologous Dendritic Cells Pulsed with Allogeneic Tumor Cell Lysate in Mesothelioma: From Mouse to Human.

    Science.gov (United States)

    Aerts, Joachim G J V; de Goeje, Pauline L; Cornelissen, Robin; Kaijen-Lambers, Margaretha E H; Bezemer, Koen; van der Leest, Cor H; Mahaweni, Niken M; Kunert, André; Eskens, Ferry A L M; Waasdorp, Cynthia; Braakman, Eric; van der Holt, Bronno; Vulto, Arnold G; Hendriks, Rudi W; Hegmans, Joost P J J; Hoogsteden, Henk C

    2018-02-15

    Purpose: Mesothelioma has been regarded as a nonimmunogenic tumor, which is also shown by the low response rates to treatments targeting the PD-1/PD-L1 axis. Previously, we demonstrated that autologous tumor lysate-pulsed dendritic cell (DC) immunotherapy increased T-cell response toward malignant mesothelioma. However, the use of autologous tumor material hampers implementation in large clinical trials, which might be overcome by using allogeneic tumor cell lines as tumor antigen source. The purpose of this study was to investigate whether allogeneic lysate-pulsed DC immunotherapy is effective in mice and safe in humans. Experimental Design: First, in two murine mesothelioma models, mice were treated with autologous DCs pulsed with either autologous or allogeneic tumor lysate or injected with PBS (negative control). Survival and tumor-directed T-cell responses of these mice were monitored. Results were taken forward in a first-in-human clinical trial, in which 9 patients were treated with 10, 25, or 50 million DCs per vaccination. DC vaccination consisted of autologous monocyte-derived DCs pulsed with tumor lysate from five mesothelioma cell lines. Results: In mice, allogeneic lysate-pulsed DC immunotherapy induced tumor-specific T cells and led to an increased survival, to a similar extent as DC immunotherapy with autologous tumor lysate. In the first-in-human clinical trial, no dose-limiting toxicities were established and radiographic responses were observed. Median PFS was 8.8 months [95% confidence interval (CI), 4.1-20.3] and median OS not reached (median follow-up = 22.8 months). Conclusions: DC immunotherapy with allogeneic tumor lysate is effective in mice and safe and feasible in humans. Clin Cancer Res; 24(4); 766-76. ©2017 AACR . ©2017 American Association for Cancer Research.

  7. Regulation of gene expression and subcellular protein distribution in MLO-Y4 osteocytic cells by lysophosphatidic acid: Relevance to dendrite outgrowth.

    Energy Technology Data Exchange (ETDEWEB)

    Waters, Katrina M.; Jacobs, Jon M.; Gritsenko, Marina A.; Karin, Norman J.

    2011-02-26

    Osteoblastic and osteocytic cells are highly responsive to the lipid growth factor lysophosphatidic acid (LPA) but the mechanisms by which LPA alters bone cell functions are largely unknown. A major effect of LPA on osteocytic cells is the stimulation of dendrite membrane outgrowth, a process that we predicted to require changes in gene expression and protein distribution. We employed DNA microarrays for global transcriptional profiling of MLO-Y4 osteocytic cells grown for 6 and 24h in the presence or absence of LPA. We identified 932 transcripts that displayed statistically significant changes in abundance of at least 1.25-fold in response to LPA treatment. Gene ontology (GO) analysis revealed that the regulated gene products were linked to diverse cellular processes, including DNA repair, response to unfolded protein, ossification, protein-RNA complex assembly, and amine biosynthesis. Gene products associated with the regulation of actin microfilament dynamics displayed the most robust expression changes, and LPA-induced dendritogenesis in vitro was blocked by the stress fiber inhibitor cytochalasin D. Mass spectrometry-based proteomic analysis of MLO-Y4 cells revealed significant LPA-induced changes in the abundance of 284 proteins at 6h and 844 proteins at 24h. GO analysis of the proteomic data linked the effects of LPA to cell processes that control of protein distribution and membrane outgrowth, including protein localization, protein complex assembly, Golgi vesicle transport, cytoskeleton-dependent transport, and membrane invagination/endocytosis. Dendrites were isolated from LPA-treated MLO-Y4 cells and subjected to proteomic analysis to quantitatively assess the subcellular distribution of proteins. Sets of 129 and 36 proteins were enriched in the dendrite fraction as compared to whole cells after 6h and 24h of LPA exposure, respectively. Protein markers indicated that membranous organelles were largely excluded from the dendrites. Highly represented among

  8. Pemetrexed plus dendritic cells as third-line therapy for metastatic esophageal squamous cell carcinoma

    Directory of Open Access Journals (Sweden)

    Zhang B

    2016-06-01

    Full Text Available Bin Zhang,1,* Rui Li,2,3,* Chun-Xiao Chang,2,3 Yong Han,2,3 Sheng-Bin Shi,2,3 Jing Tian2,3 1Department of Medical Oncology, Shandong Ji Ning First People’s Hospital, 2Department of Medical Oncology, Shandong Cancer Hospital, Shandong University, Shandong 3Department of Medical Oncology, Shandong Cancer Hospital and Institute, Shandong Academy of Medical Sciences, Jinan, People’s Republic of China*These authors contributed equally to this workAbstract: This study was conducted to evaluate the toxicity and efficacy of pemetrexed plus dendritic cells (DCs when administered as third-line treatment for metastatic esophageal squamous cell carcinoma (ESCC. All patients in the study group had previously failed first-line treatment with 5-fluorouracil and cisplatin-based regimens, as well as second-line treatment with taxane-based regimens. A total of 31 patients were treated with pemetrexed (500 mg/m2 plus DCs on day 1, every 3 weeks. DCs were given for one cycle of 21 days. Thirty patients were evaluated for their response. No patient had a complete response, three patients (10.0% had a partial response, ten patients (33.3% had stable disease, and 17 patients (56.7% had progressive disease. The overall response rate was 10.0%. The median progression-free survival (PFS time was 2.9 months (95% CI, 2.7–3.2, and the median overall survival (OS time was 7.1 months (95% CI, 6.4–7.9. The median PFS and OS times among patients with high and low levels of miR-143 expression in their blood serum were significantly different: median PFS times =3.2 months (95% CI, 2.9–3.4 and 2.7 months (95% CI, 2.4–3.0, respectively (P=0.017, and median OS times =7.8 months (95% CI, 6.8–8.9 and 6.3 months (95% CI, 5.3–7.3, respectively (P=0.036. No patient experienced Grade 4 toxicity. Combined third-line treatment with pemetrexed and DCs was marginally effective and well tolerated in patients with advanced ESCC. Serum miR-143 levels are a potential

  9. Modular expression analysis reveals functional conservation between human Langerhans cells and mouse cross-priming dendritic cells

    OpenAIRE

    Artyomov, Maxim N.; Munk, Adiel; Gorvel, Laurent; Korenfeld, Daniel; Cella, Marina; Tung, Thomas; Klechevsky, Eynav

    2015-01-01

    Characterization of functionally distinct dendritic cell (DC) subsets in mice has fueled interest in whether analogous counterparts exist in humans. Transcriptional modules of coordinately expressed genes were used for defining shared functions between the species. Comparing modules derived from four human skin DC subsets and modules derived from the Immunological Genome Project database for all mouse DC subsets revealed that human Langerhans cells (LCs) and the mouse XCR1+CD8?+CD103+ DCs sha...

  10. Mast-Cell-Derived TNF Amplifies CD8+ Dendritic Cell Functionality and CD8+ T Cell Priming

    Directory of Open Access Journals (Sweden)

    Jan Dudeck

    2015-10-01

    Full Text Available Mast cells are critical promoters of adaptive immunity in the contact hypersensitivity model, but the mechanism of allergen sensitization is poorly understood. Using Mcpt5-CreTNFFL/FL mice, we show here that the absence of TNF exclusively in mast cells impaired the expansion of CD8+ T cells upon sensitization and the T-cell-driven adaptive immune response to elicitation. T cells primed in the absence of mast cell TNF exhibited a diminished efficiency to transfer sensitization to naive recipients. Specifically, mast cell TNF promotes CD8+ dendritic cell (DC maturation and migration to draining lymph nodes. The peripherally released mast cell TNF further critically boosts the CD8+ T-cell-priming efficiency of CD8+ DCs, thereby linking mast cell effects on T cells to DC modulation. Collectively, our findings identify the distinct potential of mast cell TNF to amplify CD8+ DC functionality and CD8+ T-cell-dominated adaptive immunity, which may be of great importance for immunotherapy and vaccination approaches.

  11. A Simulation Study on the Effects of Dendritic Morphology on Layer V Prefontal Pyramidal Cell Firing Behavior

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    Maria ePsarrou

    2014-09-01

    Full Text Available Pyramidal cells, the most abundant neurons in neocortex, exhibit significant structural variability across different brain areas and layers in different species. Moreover, in response to a somatic step current, these cells display a range of firing behaviors, the most common being (1 repetitive action potentials (Regular Spiking - RS, and (2 an initial cluster of 2-5 action potentials with short ISIs followed by single spikes (Intrinsic Bursting - IB. A correlation between firing behavior and dendritic morphology has recently been reported. In this work we use computational modeling to investigate quantitatively the effects of the basal dendritic tree morphology on the firing behavior of 112 three-dimensional reconstructions of layer V PFC rat pyramidal cells. Particularly, we focus on how different morphological (diameter, total length, volume and branch number and passive (Mean Electrotonic Path length features of basal dendritic trees shape somatic firing when the spatial distribution of ionic mechanisms in the basal dendritic trees is uniform or non-uniform. Our results suggest that total length, volume and branch number are the best morphological parameters to discriminate the cells as RS or IB, regardless of the distribution of ionic mechanisms in basal trees. The discriminatory power of total length, volume and branch number remains high in the presence of different apical dendrites. These results suggest that morphological variations in the basal dendritic trees of layer V pyramidal neurons in the PFC influence their firing patterns in a predictive manner and may in turn influence the information processing capabilities of these neurons.

  12. Apoptotic Cells Induced Signaling for Immune Homeostasis in Macrophages and Dendritic Cells

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    Uriel Trahtemberg

    2017-10-01

    Full Text Available Inefficient and abnormal clearance of apoptotic cells (efferocytosis contributes to systemic autoimmune disease in humans and mice, and inefficient chromosomal DNA degradation by DNAse II leads to systemic polyarthritis and a cytokine storm. By contrast, efficient clearance allows immune homeostasis, generally leads to a non-inflammatory state for both macrophages and dendritic cells (DCs, and contributes to maintenance of peripheral tolerance. As many as 3 × 108 cells undergo apoptosis every hour in our bodies, and one of the primary “eat me” signals expressed by apoptotic cells is phosphatidylserine (PtdSer. Apoptotic cells themselves are major contributors to the “anti-inflammatory” nature of the engulfment process, some by secreting thrombospondin-1 (TSP-1 or adenosine monophosphate and possibly other immune modulating “calm-down” signals that interact with macrophages and DCs. Apoptotic cells also produce “find me” and “tolerate me” signals to attract and immune modulate macrophages and DCs that express specific receptors for some of these signals. Neither macrophages nor DCs are uniform, and each cell type may variably express membrane proteins that function as receptors for PtdSer or for opsonins like complement or opsonins that bind to PtdSer, such as protein S and growth arrest-specific 6. Macrophages and DCs also express scavenger receptors, CD36, and integrins that function via bridging molecules such as TSP-1 or milk fat globule-EGF factor 8 protein and that differentially engage in various multi-ligand interactions between apoptotic cells and phagocytes. In this review, we describe the anti-inflammatory and pro-homeostatic nature of apoptotic cell interaction with the immune system. We do not review some forms of immunogenic cell death. We summarize the known apoptotic cell signaling events in macrophages and DCs that are related to toll-like receptors, nuclear factor kappa B, inflammasome, the lipid

  13. Brucella β 1,2 cyclic glucan is an activator of human and mouse dendritic cells.

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    Anna Martirosyan

    Full Text Available Bacterial cyclic glucans are glucose polymers that concentrate within the periplasm of alpha-proteobacteria. These molecules are necessary to maintain the homeostasis of the cell envelope by contributing to the osmolarity of Gram negative bacteria. Here, we demonstrate that Brucella β 1,2 cyclic glucans are potent activators of human and mouse dendritic cells. Dendritic cells activation by Brucella β 1,2 cyclic glucans requires TLR4, MyD88 and TRIF, but not CD14. The Brucella cyclic glucans showed neither toxicity nor immunogenicity compared to LPS and triggered antigen-specific CD8(+ T cell responses in vivo. These cyclic glucans also enhanced antigen-specific CD4(+ and CD8(+ T cell responses including cross-presentation by different human DC subsets. Brucella β 1,2 cyclic glucans increased the memory CD4(+ T cell responses of blood mononuclear cells exposed to recombinant fusion proteins composed of anti-CD40 antibody and antigens from both hepatitis C virus and Mycobacterium tuberculosis. Thus cyclic glucans represent a new class of adjuvants, which might contribute to the development of effective antimicrobial therapies.

  14. Plasmacytoid dendritic cells in cutaneous lesions of patients with chromoblastomycosis, lacaziosis, and paracoccidioidomycosis: a comparative analysis.

    Science.gov (United States)

    Pagliari, Carla; Kanashiro-Galo, Luciane; Silva, Aline Alves de Lima; Barboza, Tânia Cristina; Criado, Paulo Ricardo; Duarte, Maria Irma Seixas; Brito, Arival Cardoso de; Xavier, Marília Brasil; Unger, Deborah; Maria Moraes Oliveira, Clivia; Quaresma, Juarez Antonio Simões; Sotto, Mirian Nacagami

    2014-05-01

    Plasmacytoid dendritic cells (pDCs) are characterized by expression of CD123 and BDCA-2 (Blood Dendritic Cell Antigen 2) (CD303) molecules, which are important in innate and adaptive immunity. Chromoblastomycosis (CBM), lacaziosis or Jorge Lobo's disease (JLD), and paracoccidioidomycosis (PCM), are noteworthy in Latin America due to the large number of reported cases. The severity of lesions is mainly determined by the host's immune status and in situ responses. The dendritic cells studied in these fungal diseases are of myeloid origin, such as Langerhans cells and dermal dendrocytes; to our knowledge, there are no data for pDCs. Forty-three biopsies from patients with CBM, 42 from those with JLD and 46 diagnosed with PCM, were evaluated by immunohistochemistry. Plasmacytoid cells immunostained with anti-CD123 and anti-CD303 were detected in 16 cases of CBM; in those stained with anti-CD123, 24 specimens were obtained from PCM. We did not detect the presence of pDCs in any specimen using either antibody in JLD. We believe that, albeit a secondary immune response in PCM and CBM, pDCs could act as a secondary source of important cytokines. The BDCA-2 (CD303) is a c-type lectin receptor involved in cell adhesion, capture, and processing of antigens. Through the expression of the c-lectin receptor, there could be an interaction with fungi, similar to other receptors of this type, namely, CD207 in PCM and CD205 and CD209 in other fungal infections. In JLD, the absence of expression of CD123 and CD303 seems to indicate that pDCs are not involved in the immune response.

  15. Blastic plasmacytoid dendritic cell neoplasm: update on molecular biology, diagnosis, and therapy.

    Science.gov (United States)

    Riaz, Wasif; Zhang, Ling; Horna, Pedro; Sokol, Lubomir

    2014-10-01

    Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematological malignancy with an aggressive clinical course. Most patients with BPDCN have skin lesions and simultaneous involvement of the peripheral blood, bone marrow, and lymph nodes. A search of PubMed and Medline was conducted for English-written articles relating to BPDCN, CD4(+)CD56(+) hematodermic neoplasm, and blastic natural killer cell lymphoma. Data regarding diagnosis, prognosis, and treatment were analyzed. BPDCN is derived from precursor plasmacytoid dendritic cells. The diagnosis of BPDCN is based on the characteristic cytology and immunophenotype of malignant cells coexpressing CD4, CD56, CD123, blood dendritic cell antigens 2 and 4, and CD2AP markers. Multiple chromosomal abnormalities and gene mutations previously reported in patients with myeloid and selected lymphoid neoplasms were identified in approximately 60% of patients with BPDCN. Prospectively controlled studies to guide treatment decisions are lacking. The overall response rate with aggressive acute lymphoblastic leukemia-type induction regimens was as high as 90%, but the durability of response was short. Median survival rates ranged between 12 and 16 months. Patients with relapsed disease may respond to L-asparaginase-containing regimens. Allogeneic hematopoietic stem cell transplantation, particularly when performed during the first remission, may produce durable remissions in selected adults. BPDCN is a rare aggressive disease that typically affects elderly patients. The most commonly affected nonhematopoietic organ is the skin. Although BPDCN is initially sensitive to conventional chemotherapy regimens, this response is relatively short and long-term prognosis is poor. In the near future, novel targeted therapies may improve outcomes for patients with BPDCN.

  16. Differential activation behavior of dermal dendritic cells underlies the strain-specific Th1 responses to single epicutaneous immunization.

    Science.gov (United States)

    Lee, Chih-Hung; Chen, Jau-Shiuh; Chiu, Hsien-Ching; Hong, Chien-Hui; Liu, Ching-Yi; Ta, Yng-Cun; Wang, Li-Fang

    2016-12-01

    Epicutaneous immunization with allergens is an important sensitization route for atopic dermatitis. We recently showed in addition to the Th2 response following single epicutaneous immunization, a remarkable Th1 response is induced in B6 mice, but not in BALB/c mice, mimicking the immune response to allergens in human non-atopics and atopics. We investigated the underlying mechanisms driving this differential Th1 response between BALB/c and B6 mice. We characterized dermal dendritic cells by flow cytometric analysis. We measured the induced Th1/Th2 responses by measuring the IFN-γ/IL-13 contents of supernatants of antigen reactivation cultures of lymph node cells. We demonstrate that more dermal dendritic cells with higher activation status migrate into draining lymph nodes of B6 mice compared to BALB/c mice. Dermal dendritic cells of B6 mice have a greater ability to capture protein antigen than those of BALB/c mice. Moreover, increasing the activation status or amount of captured antigen in dermal dendritic cells induced a Th1 response in BALB/c mice. Further, differential activation behavior, but not antigen-capturing ability of dermal dendritic cells between BALB/c and B6 mice is dendritic cell-intrinsic. These results show that the differential activation behavior of dermal dendritic cells underlies the strain-specific Th1 responses following single epicutaneous immunization. Furthermore, our findings highlight the potential differences between human atopics and non-atopics and provide useful information for the prediction and prevention of atopic diseases. Copyright © 2016 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  17. Requirement of Interaction between Mast Cells and Skin Dendritic Cells to Establish Contact Hypersensitivity

    Science.gov (United States)

    Otsuka, Atsushi; Kubo, Masato; Honda, Tetsuya; Egawa, Gyohei; Nakajima, Saeko; Tanizaki, Hideaki; Kim, Bongju; Matsuoka, Satoshi; Watanabe, Takeshi; Nakae, Susumu; Miyachi, Yoshiki; Kabashima, Kenji

    2011-01-01

    The role of mast cells (MCs) in contact hypersensitivity (CHS) remains controversial. This is due in part to the use of the MC-deficient Kit W/Wv mouse model, since Kit W/Wv mice congenitally lack other types of cells as a result of a point mutation in c-kit. A recent study indicated that the intronic enhancer (IE) for Il4 gene transcription is essential for MCs but not in other cell types. The aim of this study is to re-evaluate the roles of MCs in CHS using mice in which MCs can be conditionally and specifically depleted. Transgenic Mas-TRECK mice in which MCs are depleted conditionally were newly generated using cell-type specific gene regulation by IE. Using this mouse, CHS and FITC-induced cutaneous DC migration were analyzed. Chemotaxis assay and cytoplasmic Ca2+ imaging were performed by co-culture of bone marrow-derived MCs (BMMCs) and bone marrow-derived dendritic cells (BMDCs). In Mas-TRECK mice, CHS was attenuated when MCs were depleted during the sensitization phase. In addition, both maturation and migration of skin DCs were abrogated by MC depletion. Consistently, BMMCs enhanced maturation and chemotaxis of BMDC in ICAM-1 and TNF-α dependent manners Furthermore, stimulated BMDCs increased intracellular Ca2+ of MC upon direct interaction and up-regulated membrane-bound TNF-α on BMMCs. These results suggest that MCs enhance DC functions by interacting with DCs in the skin to establish the sensitization phase of CHS. PMID:21980488

  18. Requirement of interaction between mast cells and skin dendritic cells to establish contact hypersensitivity.

    Directory of Open Access Journals (Sweden)

    Atsushi Otsuka

    Full Text Available The role of mast cells (MCs in contact hypersensitivity (CHS remains controversial. This is due in part to the use of the MC-deficient Kit (W/Wv mouse model, since Kit (W/Wv mice congenitally lack other types of cells as a result of a point mutation in c-kit. A recent study indicated that the intronic enhancer (IE for Il4 gene transcription is essential for MCs but not in other cell types. The aim of this study is to re-evaluate the roles of MCs in CHS using mice in which MCs can be conditionally and specifically depleted. Transgenic Mas-TRECK mice in which MCs are depleted conditionally were newly generated using cell-type specific gene regulation by IE. Using this mouse, CHS and FITC-induced cutaneous DC migration were analyzed. Chemotaxis assay and cytoplasmic Ca²⁺ imaging were performed by co-culture of bone marrow-derived MCs (BMMCs and bone marrow-derived dendritic cells (BMDCs. In Mas-TRECK mice, CHS was attenuated when MCs were depleted during the sensitization phase. In addition, both maturation and migration of skin DCs were abrogated by MC depletion. Consistently, BMMCs enhanced maturation and chemotaxis of BMDC in ICAM-1 and TNF-α dependent manners Furthermore, stimulated BMDCs increased intracellular Ca²⁺ of MC upon direct interaction and up-regulated membrane-bound TNF-α on BMMCs. These results suggest that MCs enhance DC functions by interacting with DCs in the skin to establish the sensitization phase of CHS.

  19. Self-glycolipids modulate dendritic cells changing the cytokine profiles of committed autoreactive T cells.

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    Karsten Buschard

    Full Text Available The impact of glycolipids of non-mammalian origin on autoimmune inflammation has become widely recognized. Here we report that the naturally occurring mammalian glycolipids, sulfatide and β-GalCer, affect the differentiation and the quality of antigen presentation by monocyte-derived dendritic cells (DCs. In response to sulfatide and β-GalCer, monocytes develop into immature DCs with higher expression of HLA-DR and CD86 but lower expression of CD80, CD40 and CD1a and lower production of IL-12 compared to non-modulated DCs. Self-glycolipid-modulated DCs responded to lipopolysaccharide (LPS by changing phenotype but preserved low IL-12 production. Sulfatide, in particular, reduced the capacity of DCs to stimulate autoreactive Glutamic Acid Decarboxylase (GAD65 - specific T cell response and promoted IL-10 production by the GAD65-specific clone. Since sulfatide and β-GalCer induced toll-like receptor (TLR-mediated signaling, we hypothesize that self-glycolipids deliver a (tolerogenic polarizing signal to differentiating DCs, facilitating the maintenance of self-tolerance under proinflammatory conditions.

  20. Dendritic Cell-Based Genetic Immunotherapy for Ovarian Cancer

    Science.gov (United States)

    2008-12-01

    Romanowski staining. As shown in Fig. 5.4, the hematoxylin and eosin staining of liver sections revealed increased infiltration of immune cells in the...T-Ag showed an absence of infiltration by immune cells, similar to control naïve mice. The Romanowski staining of the liver sections revealed there...CFm40L). 83 PBS Ad-SV40 Ad-SV40 + CFm40L Figure 5.5 Romanowski staining of liver tissue from B6C3F1 mice immunized using CD40-targeted Ad5

  1. Potassium conductances mediate bidirectional state-dependent modulation of action potential evoked dendritic calcium signals in dentate gyrus granule cells

    Directory of Open Access Journals (Sweden)

    János Brunner

    2014-03-01

    Full Text Available Backpropagating action potentials (bAPs and local calcium signals that they trigger are fundamental for dendritic functions. Here we addressed the question what extent the changes of local dendritic membrane properties can contribute to the shaping of the coupling between dendritic action potentials and the local calcium responses. Using a combination of in vitro electrophysiological and confocal imaging techniques we found that activation of dendritic GIRK channels via mGlu2 or GABAB receptors enhanced the bAP¬-triggered calcium signals in the dendrites of dentate gyrus granule cells (GCs. The enhancement of calcium signals was significant only in those dendritic regions, where these receptors are predominantly expressed. Similarly to GIRK channel activation, somatic hyperpolarization by DC current injection (from -64 mV to -77 mV, significantly increased bAP-associated calcium signals in the proximal dendrites. The hyperpolarization was associated with a decrease in the input resistance due to the rectification of the membrane potential of GCs. The effect of hyperpolarization on the calcium signals was maintained when T-type calcium currents were blocked but it decreased when GIRK channels were inhibited. Simultaneous dual somato-dendritic recordings from GCs showed that somatic hyperpolarization accelerated the repolarization phase of dendritic bAP in the proximal region whereas the rising phase and peak amplitude was not affected. We hypothesize that the larger driving force for calcium ions during the faster repolarization can contribute to the increasing in calcium signals. Employment of previously recorded dendritic bAP waveforms from hyperpolarized membrane potential as voltage command evoked larger calcium currents in nucleated patches compared to bAP waveform from the same recording at depolarized membrane potential. Furthermore, addition of native, high-voltage activated, inactivating potassium conductance by somatic dynamic clamp

  2. Ubiquitination regulates MHC class II-peptide complex retention and degradation in dendritic cells

    OpenAIRE

    Walseng, Even; Furuta, Kazuyuki; Bosch, Berta; Weih, Karis A.; Matsuki, Yohei; Bakke, Oddmund; Ishido, Satoshi; Roche, Paul A.

    2010-01-01

    The expression and turnover of MHC class II-peptide complexes (pMHC-II) on the surface of dendritic cells (DCs) is essential for their ability to activate CD4 T cells efficiently. The half-life of surface pMHC-II is significantly greater in activated (mature) DCs than in resting (immature) DCs, but the molecular mechanism leading to this difference remains unknown. We now show that ubiquitination of pMHC-II by the E3 ubiquitin ligase membrane-associated RING-CH 1 (March-I) regulates surface e...

  3. Induction of immune responses in vivo with small numbers of veiled (dendritic) cells.

    OpenAIRE

    Knight, S C; Mertin, J; Stackpoole, A; Clark, J

    1983-01-01

    The role of dendritic or veiled cells (VC) from lymph nodes or spleens of rats and mice in initiating immune responses in vivo has been investigated. Host-versus-graft responses were induced by injection of VC from spleens of (C57BL/10 X CBA) F1 mice into the footpads of parental strain (CBA) animals and measured by the increase in the weight of the draining popliteal lymph nodes. The potency of VC to induce the responses was 100-fold greater than that of unseparated spleen cells. The in vivo...

  4. Dendritic-cell-based technology landscape: Insights from patents and citation networks

    Science.gov (United States)

    Kong, Xiangjun; Hu, Yuanjia; Cai, Zhifang; Yang, Fengqing; Zhang, Qianru

    2015-01-01

    As the most potent antigen-presenting cells, dendritic cells (DCs) are pivotal players in regulating immune responses. DC-based technologies have generated a series of typical and promising therapeutic options, especially after the first DC-based cancer vaccine was approved by US. Food and Drug Administration (US. FDA). In this context, this paper employs patents and citation networks to conduct a fundamental analysis in order to show overall landscape of DC-based technologies. The results in this research can be used as references for decision-making in developing efficacious DC therapeutic products. PMID:25714961

  5. Immune modulation by dendritic-cell-based cancer vaccines

    Indian Academy of Sciences (India)

    2017-01-31

    Jan 31, 2017 ... 5. Molecular mechanism of action of. DC-based cancer vaccines. DC-based vaccines aim to load DCs with tumour antigens ex vivo or in vivo followed by maturation of DCs that leads to their activation. Upon infusion into the patient, the ex vivo mature DCs generate anti-tumour T-cell responses resulting.

  6. Mannose receptor is highly expressed by peritoneal dendritic cells in endometriosis.

    Science.gov (United States)

    Izumi, Gentaro; Koga, Kaori; Takamura, Masashi; Makabe, Tomoko; Nagai, Miwako; Urata, Yoko; Harada, Miyuki; Hirata, Tetsuya; Hirota, Yasushi; Fujii, Tomoyuki; Osuga, Yutaka

    2017-01-01

    To characterize peritoneal dendritic cells (DCs) in endometriosis and to clarify their role in its etiology. Experimental. University hospital. Sixty-three women (35 patients with endometriosis and 28 control women) who had undergone laparoscopic surgery. Peritoneal DCs from endometriosis and control samples were analyzed for the expression of cell surface markers. Monocyte-derived dendritic cells (Mo-DCs) were cultured with dead endometrial stromal cells (dESCs) to investigate changes in phagocytic activity and cytokine expression. Cell surface markers and cytokine expression and identification with the use of flow cytometry or reverse-transcription polymerase chain reaction (RT-PCR). Changes in cytokine expression and phagocytic activity of Mo-DCs cultured with dESCs and d-mannan were measured with the use of flow cytometry and RT-PCR. The proportion of mannose receptor (MR)-positive myeloid DC type 1 was higher in endometriosis samples than in control samples. The blocking of MR reduced phagocytosis of dESCs by Mo-DCs. Mo-DCs cultured with dESCs expressed higher levels of interleukin (IL) 1β and IL-6 than control samples. Peritoneal DCs in endometriosis tissue express high levels of MR, which promotes phagocytosis of dead endometrial cells and thereby contributes to the etiology of endometriosis. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  7. 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.

  8. Generation of functional CD8+ T Cells by human dendritic cells expressing glypican-3 epitopes

    Directory of Open Access Journals (Sweden)

    Farzaneh Farzin

    2010-05-01

    Full Text Available Abstract Background Glypican 3 (GPC-3 is an oncofoetal protein that is expressed in most hepatocellular carcinomas (HCC. Since it is a potential target for T cell immunotherapy, we investigated the generation of functional, GPC-3 specific T cells from peripheral blood mononuclear cells (PBMC. Methods Dendritic cells (DC were derived from adherent PBMC cultured at 37°C for 7 days in X-Vivo, 1% autologous plasma, and 800 u/ml GM-CSF plus 500 u/ml IL-4. Immature DC were transfected with 20 μg of in vitro synthesised GPC-3 mRNA by electroporation using the Easy-ject plus system (Equibio, UK (300 V, 150 μF and 4 ms pulse time, or pulsed with peptide, and subsequently matured with lipopolysaccharide (LPS. Six predicted GPC-3 peptide epitopes were synthesized using standard f-moc technology and tested for their binding affinity to HLA-A2.1 molecules using the cell line T2. Results DC transfected with GPC-3 mRNA but not control DC demonstrated strong intracellular staining for GPC-3 and in vitro generated interferon-gamma expressing T cells from autologous PBMC harvested from normal subjects. One peptide, GPC-3522-530 FLAELAYDL, fulfilled our criteria as a naturally processed, HLA-A2-restricted cytotoxic T lymphocyte (CTL epitope: i it showed high affinity binding to HLA-A2, in T2 cell binding assay; ii it was generated by the MHC class I processing pathway in DC transfected with GPC-3 mRNA, and iii HLA-A2 positive DC loaded with the peptide stimulated proliferation in autologous T cells and generated CTL that lysed HLA-A2 and GPC-3 positive target cells. Conclusions These findings demonstrate that electroporation of GPC-3 mRNA is an efficient method to load human monocyte-derived DC with antigen because in vitro they generated GPC-3-reactive T cells that were functional, as shown by interferon-gamma production. Furthermore, this study identified a novel naturally processed, HLA-A2-restricted CTL epitope, GPC-3522-530 FLAELAYDL, which can be used to

  9. A mouse model of visual perceptual learning reveals alterations in neuronal coding and dendritic spine density in the visual cortex

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    Yan eWang

    2016-03-01

    Full Text Available Visual perceptual learning (VPL can improve spatial vision in normally sighted and visually impaired individuals. Although previous studies of humans and large animals have explored the neural basis of VPL, elucidation of the underlying cellular and molecular mechanisms remains a challenge. Owing to the advantages of molecular genetic and optogenetic manipulations, the mouse is a promising model for providing a mechanistic understanding of VPL. Here, we thoroughly evaluated the effects and properties of VPL on spatial vision in C57BL/6J mice using a two-alternative, forced-choice visual water task. Briefly, the mice underwent prolonged training at near the individual threshold of contrast or spatial frequency (SF for pattern discrimination or visual detection for 35 consecutive days. Following training, the contrast-threshold trained mice showed an 87% improvement in contrast sensitivity (CS and a 55% gain in visual acuity (VA. Similarly, the SF-threshold trained mice exhibited comparable and long-lasting improvements in VA and significant gains in CS over a wide range of SFs. Furthermore, learning largely transferred across eyes and stimulus orientations. Interestingly, learning could transfer from a pattern discrimination task to a visual detection task, but not vice versa. We validated that this VPL fully restored VA in adult amblyopic mice and old mice. Taken together, these data indicate that mice, as a species, exhibit reliable VPL. Intrinsic signal optical imaging revealed that mice with perceptual training had higher cut-off SFs in primary visual cortex (V1 than those without perceptual training. Moreover, perceptual training induced an increase in the dendritic spine density in layer 2/3 pyramidal neurons of V1. These results indicated functional and structural alterations in V1 during VPL. Overall, our VPL mouse model will provide a platform for investigating the neurobiological basis of VPL.

  10. 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...... generation and to be superior to the standard DC (sDC) cocktail as it induced fully mature DCs with potent IL-12p70 secretion together with CCR7 expression which is necessary for priming of a TH1 response and for migration to the draining lymph node, respectively. In this study, we tested the adaptation...

  11. A Rapid Culture Technique Produces Functional Dendritic-Like Cells from Human Acute Myeloid Leukemia Cell Lines

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    Jian Ning

    2011-01-01

    Full Text Available Most anti-cancer immunotherapeutic strategies involving dendritic cells (DC as vaccines rely upon the adoptive transfer of DC loaded with exogenous tumour-peptides. This study utilized human acute myeloid leukemia (AML cells as progenitors from which functional dendritic-like antigen presenting cells (DLC were generated, that constitutively express tumour antigens for recognition by CD8+ T cells. DLC were generated from AML cell lines KG-1 and MUTZ-3 using rapid culture techniques and appropriate cytokines. DLC were evaluated for their cell-surface phenotype, antigen uptake and ability to stimulate allogeneic responder cell proliferation, and production of IFN-γ; compared with DC derived from normal human PBMC donors. KG-1 and MUTZ-3 DLC increased expression of CD80, CD83, CD86, and HLA-DR, and MUTZ-3 DLC downregulated CD14 and expressed CD1a. Importantly, both KG-1 and MUTZ-3-derived DLC promoted proliferation of allogeneic responder cells more efficiently than unmodified cells; neither cells incorporated FITC-labeled dextran, but both stimulated IFN-γ production from responding allogeneic CD8+ T cells. Control DC produced from PBMC using the FastDC culture also expressed high levels of critical cell surface ligands and demonstrated good APC function. This paper indicates that functional DLC can be cultured from the AML cell lines KG-1 and MUTZ-3, and FastDC culture generates functional KG-1 DLC.

  12. Surfactant Protein D modulates HIV infection of both T-cells and dendritic cells.

    Directory of Open Access Journals (Sweden)

    Jens Madsen

    Full Text Available Surfactant Protein D (SP-D is an oligomerized C-type lectin molecule with immunomodulatory properties and involvement in lung surfactant homeostasis in the respiratory tract. SP-D binds to the enveloped viruses, influenza A virus and respiratory syncytial virus and inhibits their replication in vitro and in vivo. SP-D has been shown to bind to HIV via the HIV envelope protein gp120 and inhibit infectivity in vitro. Here we show that SP-D binds to different strains of HIV (BaL and IIIB and the binding occurs at both pH 7.4 and 5.0 resembling physiological relevant pH values found in the body and the female urogenital tract, respectively. The binding of SP-D to HIV particles and gp120 was inhibited by the presence of several hexoses with mannose found to be the strongest inhibitor. Competition studies showed that soluble CD4 and CVN did not interfere with the interaction between SP-D and gp120. However, soluble recombinant DC-SIGN was shown to inhibit the binding between SP-D and gp120. SP-D agglutinated HIV and gp120 in a calcium dependent manner. SP-D inhibited the infectivity of HIV strains at both pH values of 7.4 and 5.0 in a concentration dependent manner. The inhibition of the infectivity was abolished by the presence of mannose. SP-D enhanced the binding of HIV to immature monocyte derived dendritic cells (iMDDCs and was also found to enhance HIV capture and transfer to the T-cell like line PM1. These results suggest that SP-D can bind to and inhibit direct infection of T-cells by HIV but also enhance the transfer of infectious HIV particles from DCs to T-cells in vivo.

  13. Layers of dendritic cell-mediated T cell tolerance, their regulation and the prevention of autoimmunity

    Directory of Open Access Journals (Sweden)

    Christian Thomas Mayer

    2012-07-01

    Full Text Available The last decades of Nobel prize-honored research have unequivocally proven a key role of dendritic cells (DCs at controlling both T cell immunity and tolerance. A tight balance between these opposing DC functions ensures immune homeostasis and host integrity. Its perturbation could explain pathological conditions such as the attack of self tissues, chronic infections and tumor immune evasion. While recent insights into the complex DC network help to unde