Search results for "dendritic cell"
showing 10 items of 447 documents
Enhanced production of CCL18 by tolerogenic dendritic cells is associated with inhibition of allergic airway reactivity
2012
Background IL-10–treated dendritic cells (DCs) have been shown to inhibit T-cell responses through induction of anergy and regulatory T cells in various model systems, including allergic inflammation, but the factors being involved in this inhibition are still unclear. Objective This study set out to analyze such factors produced or induced by IL-10–treated DCs by using gene expression profiling and to explore their function. Methods CD4 + T cells from allergic donors were stimulated with autologous monocyte-derived allergen-pulsed mature DCs or IL-10–treated DCs. After 24 hours, the transcriptional profile was analyzed by using Affymetrix technology. Results were validated by using quantit…
Mage-3 and influenza-matrix peptide-specific cytotoxic T cells are inducible in terminal stage HLA-A2.1+ melanoma patients by mature monocyte-derived…
2000
Abstract Dendritic cell (DC) vaccination, albeit still in an early stage, is a promising strategy to induce immunity to cancer. We explored whether DC can expand Ag-specific CD8+ T cells even in far-advanced stage IV melanoma patients. We found that three to five biweekly vaccinations of mature, monocyte-derived DC (three vaccinations of 6 × 106 s.c. followed by two i.v. ones of 6 and 12 × 106, respectively) pulsed with Mage-3A2.1 tumor and influenza matrix A2.1-positive control peptides as well as the recall Ag tetanus toxoid (in three of eight patients) generated in all eight patients Ag-specific effector CD8+ T cells that were detectable in blood directly ex vivo. This is the first time …
Effects of glycation of the model food allergen ovalbumin on antigen uptake and presentation by human dendritic cells.
2010
Advanced glycation endproducts (AGEs) of food proteins resulting from the Maillard reaction after cooking or heating may have particular importance in food allergy. The underlying immunological mechanisms are only poorly understood. The aim of the study was to examine the effects of AGE derived from the model food allergen ovalbumin (AGE-OVA) on dendritic cells (DCs), their immunostimulatory capacity and the T-cell response compared with regular OVA. For this purpose, human immature DCs were exposed to fluorescein isothiocyanate (FITC)-labelled AGE-OVA and FITC-labelled regular OVA and uptake was analysed by flow cytometry and fluorescence microscopy. Furthermore, autologous CD4(+) T-cell p…
Human dendritic cells transfected with allergen-DNA stimulate specific immunoglobulin G4 but not specific immunoglobulin E production of autologous B…
2007
Atopic/allergic diseases are characterized by T helper 2 (Th2)-dominated immune responses resulting in immunoglobulin E (IgE) production. DNA-based immunotherapies have been shown to shift the immune response towards Th1 in animal models. In further studies we showed that human dendritic cells (DC) transfected with allergen-DNA are able to stimulate autologous CD4(+) T cells from atopic individuals to produce Th1 instead of Th2 cytokines and to activate interferon-gamma (IFN-gamma)-producing CD8(+) T cells. The aim of this study was to analyse whether DC transfected with allergen-DNA are also able to influence immunoglobulin production of B cells from atopic donors. For this purpose, human …
Comparison of allergen-stimulated dendritic cells from atopic and nonatopic donors dissecting their effect on autologous naive and memory T helper ce…
2000
Abstract Background: Because of their production of IL-12, mature dendritic cells (DC) are potent inducers of T H 1 responses. However, recent reports have demonstrated that DCs can also induce T H 2 differentiation. Objective: In the current study we investigated which immune response is induced by DCs in naive CD45RA + or memory CD45R0 + CD4 + T cells from atopic individuals (patients with grass pollen, birch pollen, or house dust mite allergy) compared with nonatopic control subjects. Methods: Immature DCs, generated from peripheral blood monocytes from atopic and nonatopic donors, were pulsed with the respective allergen and fully matured. Then the mature DCs were cocultured in vitro wi…
Inhibition of human allergic T-cell responses by IL-10–treated dendritic cells: Differences from hydrocortisone-treated dendritic cells
2001
Abstract Background: Dendritic cells (DCs) are able to induce human allergic T H 1 responses as well as T H 2 responses. Objective: In this study, we examined the effect of antiinflammatory agents such as IL-10 and hydrocortisone (HC) on the accessory function of DCs and the resulting T-cell response, especially that of T H 2 cells. Methods: Naive and memory CD4 + T cells from atopic donors were stimulated with autologous allergen-pulsed DCs generated from CD14 + monocytes by culture with GM-CSF/IL-4 and fully matured with IL-1β, TNF-α, and PGE 2 in the presence or absence of IL-10 or HC. Results: IL-10–treated DCs and, to a lesser extent, HC-treated DCs showed a decreased expression of MHC…
Modification of the human allergic immune response by allergen-DNA-transfected dendritic cells in vitro.
2004
Abstract Background Atopic-allergic diseases are characterized by T H 2-dominated immune responses, resulting in IgE production. DNA-based immunotherapies have been shown to shift the immune response toward a T H 1-type response in animal models. Objective The aim of the study was to analyze whether dendritic cells (DCs) transfected with allergen-DNA conjugates are able to stimulate human autologous CD4 + T cells, CD8 + T cells, or both from atopic individuals to produce T H 1 cytokines instead of T H 2 cytokines. Methods For this purpose, human mature DCs from atopic donors were transfected with an adenovirus encoding the allergen Phl p 1. Autologous CD4 + and CD8 + T cells were stimulated…
Identification of NY-ESO-1 epitopes presented by human histocompatibility antigen (HLA)-DRB4*0101-0103 and recognized by CD4(+) T lymphocytes of pati…
2000
NY-ESO-1 is a member of the cancer-testis family of tumor antigens that elicits strong humoral and cellular immune responses in patients with NY-ESO-1–expressing cancers. Since CD4+ T lymphocytes play a critical role in generating antigen-specific cytotoxic T lymphocyte and antibody responses, we searched for NY-ESO-1 epitopes presented by histocompatibility leukocyte antigen (HLA) class II molecules. Autologous monocyte-derived dendritic cells of cancer patients were incubated with recombinant NY-ESO-1 protein and used in enzyme-linked immunospot (ELISPOT) assays to detect NY-ESO-1–specific CD4+ T lymphocyte responses. To identify possible epitopes presented by distinct HLA class II allele…
CD4(+) and CD8(+) anergic T cells induced by interleukin-10-treated human dendritic cells display antigen-specific suppressor activity.
2002
Interleukin-10 (IL-10)–treated dendritic cells (DCs) induce an alloantigen- or peptide-specific anergy in various CD4+ and CD8+ T-cell populations. In the present study, we analyzed whether these anergic T cells are able to regulate antigen-specific immunity. Coculture experiments revealed that alloantigen-specific anergic CD4+ and CD8+ T cells suppressed proliferation of syngeneic T cells in a dose-dependent manner. The same effect was observed when the hemagglutinin-specific CD4+T-cell clone HA1.7 or tyrosinase-specific CD8+ T cells were cocultured with anergic T cells of the same specificity. Anergic T cells did not induce an antigen-independent bystander inhibition. Suppression was depe…
Interleukin 1α Promotes Th1 Differentiation and Inhibits Disease Progression in Leishmania major–susceptible BALB/c Mice
2003
Protective immunity against pathogens such as Leishmania major is mediated by interleukin (IL)-12–dependent Th1-immunity. We have shown previously that skin-dendritic cells (DCs) from both resistant C57BL/6 and susceptible BALB/c mice release IL-12 when infected with L. major, and infected BALB/c DCs effectively vaccinate against leishmaniasis. To determine if cytokines other than IL-12 might influence disease outcome, we surveyed DCs from both strains for production of a variety of cytokines. Skin-DCs produced significantly less IL-1α in response to lipopolysaccharide/interferon γ or L. major when expanded from BALB/c as compared with C57BL/6 mice. In addition, IL-1α mRNA accumulation in l…