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Monocyte-derived Dendritic Cells (monocyte-derived + dendritic_cell)
Selected AbstractsMonocyte-derived dendritic cells from HCV-infected patients transduced with an adenovirus expressing NS3 are functional when stimulated with the TLR3 ligand poly(I:C)JOURNAL OF VIRAL HEPATITIS, Issue 11 2008I. Echeverrķa Summary., Dendritic cells (DC) transfected with an adenovirus encoding hepatitis C virus (HCV) NS3 protein (AdNS3) induce potent antiviral immune responses when used to immunize mice. However, in HCV infected patients, controversial results have been reported regarding the functional properties of monocyte-derived DC (MoDC), a cell population commonly used in DC vaccination protocols. Thus, with the aim of future vaccination studies we decided to characterize MoDC from HCV patients transfected with AdNS3 and stimulated with the TLR3 ligand poly(I:C). Phenotypic and functional properties of these cells were compared with those from MoDC obtained from uninfected individuals. PCR analysis showed that HCV RNA was negative in MoDC from patients after the culture period. Also, phenotypic analysis of these cells showed lower expression of CD80, CD86, and CD40, but similar expression of HLA-DR molecules as compared to MoDC from uninfected individuals. Functional assays of MoDC obtained from patients and controls showed a similar ability to activate allogeneic lymphocytes or to produce IL-12 and IL-10, although lower IFN-, levels were produced by cells from HCV patients after poly(I:C) stimulation. Moreover, both groups of MoDC induced similar profiles of IFN-, and IL-5 after stimulation of allogeneic T-cells. Finally, migration assays did not reveal any difference in their ability to respond to CCL21 chemokine. In conclusion, MoDC from HCV patients are functional after transduction with AdNS3 and stimulation with poly(I:C). These findings suggest that these cells may be useful for therapeutic vaccination in chronic HCV infection. [source] Corticotropin-releasing factor decreases IL-18 in the monocyte-derived dendritic cellEXPERIMENTAL DERMATOLOGY, Issue 3 2009Hee Jung Lee Abstract:, Recent evidence suggests that crosstalk between mast cells, nerves and keratinocytes might be involved in the exacerbation of inflammatory conditions by stress, but the mechanism by which this occurs remains unclear. Corticotropin-releasing factor (CRF), which activates the hypothalamo-pituitary-adrenal (HPA) axis under stress, also has pro-inflammatory peripheral effects. However, there have been no reports about CRF receptor expression and the functional role of CRF in the dendritic cell (DC), which is considered to be the link between allergen uptake and the clinical manifestations of allergic diseases, such as atopic dermatitis. The purpose of this study was to investigate the expression of CRF receptors and the functional role of CRF in the monocyte-derived DC (MoDC) of atopic dermatitis patients and non-atopic healthy controls. In this study, mRNAs for CRF-R1, and 1,, as well as the CRF-R1 protein, were detected in MoDCs. CRF-R2, (but not R2, or R2,) mRNA and the CRF-R2 protein were present in MoDCs. Exposure of DCs to CRF resulted in a decrease of IL-18 in both atopic dermatitis patients and non-atopic healthy controls. However, CRF did not alter the expression of IL-6, CCL17, CCL18, and CCL22. Therefore, our results demonstrate that CRF could modulate immune responses by acting directly upon DCs. [source] Peptide-,2-microglobulin-major histocompatibility complex expressing cells are potent antigen-presenting cells that can generate specific T cellsIMMUNOLOGY, Issue 1 2007Sonja Obermann Summary Adoptive T-cell therapy represents a promising therapeutic approach for the treatment of cancer. Successful adoptive immunotherapy depends on the ex vivo priming and expansion of antigen-specific T cells. However, the in vitro generation of adequate numbers of functional antigen-specific T cell remains a major obstacle. It is important to develop efficient and reproducible methods to generate high numbers of antigen-specific T cells for adoptive T-cell transfer. We have developed a new artificial antigen-presenting cell (aAPC) by transfection of major histocompatibility (MHC) class I negative Daudi cells with a peptide-,2-microglobulin,MHC fusion construct (single-chain aAPC) ensuring presentation of the peptide,MHC complex of interest. Using this artificial antigen-presenting cell, we could generate up to 9·2 × 108 antigen-specific cytotoxic CD8+ T cells from 10 ml blood. In vitro generated T cells lysed endogenously presented antigens. Direct comparison of the single-chain aAPC with autologous monocyte-derived dendritic cells demonstrated that these cells were equally efficient in stimulation of T cells. Finally, we were able to generate antigen-specific T cell lines from perpheral blood mononuclear cells of patients receiving cytotoxic chemotherapy. The use of single-chain aAPC represent a promising option for the generation of antigen-specific CD8+ T cells, which could be used for adoptive T-cell therapy. [source] Differential toxicity on monocytes and monocyte-derived dendritic Cells: a new tool to differentiate allergens from irritants?INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 5 2007Laetitia Furio Phenotypic activation of monocyte-derived dendritic cells has been proposed as an in vitro alternative assay to discriminate potential sensitizers from irritants, but the sensitivity of the assay remains controversial. In this study, we first determined the dynamic range of expression of activation/maturation markers on human monocyte-derived dendritic cells cultured in the presence or absence of transforming growth factor ß (TGF,)? On day three of culture, most monocytes had already differentiated into dendritic cells that expressed low levels of costimulatory molecules especially in the presence TGF,-treatment of 3-day-old TGF,-treated monocyte-derived dendritic cells with several chemicals at sub-toxic concentrations induced significant phenotypic changes for all the strong and mild sensitizers tested, whereas the irritant sodium lauryl sulfate had no effect. However, a very large variability was observed among the experiments. Most interestingly, we could show here for the first time that at concentrations sub-toxic for monocyte-derived dendritic cells all the allergens tested induced monocyte apoptosis within 2 days of culture. In contrast, sodium lauryl sulfate displayed similar toxicity on monocytes and monocyte-derived dendritic cells and these results were confirmed with other irritants such as benzoic acid or methylsalicylate. Although testing of far more chemicals is required, these results indicate that differential toxicity of chemicals to monocytes and monocyte-derived dendritic cells could be a rapid, simple and valuable tool to differentiate sensitizers from irritants. [source] Immunotherapy using autologous monocyte-derived dendritic cells pulsed with leukemic cell lysates for acute myeloid leukemia relapse after autologous peripheral blood stem cell transplantationJOURNAL OF CLINICAL APHERESIS, Issue 2 2004Je-Jung Lee Abstract Although a second stem cell transplantation (SCT) can be used as salvage therapy in patients with relapsing leukemia after SCT, most of these patients have a poor outcome. We tried clinical vaccination using monocyte-derived dendritic cells (DCs) pulsed with leukemic lysates to treat relapsing acute myeloid leukemia (AML) after autologous SCT. To generate DCs, CD14+ cells isolated from peripheral blood stem cell products were cultured in AIM-V in the presence of GM-CSF and IL-4. Adding TNF-, on day 6 induced maturation of the DCs, which were harvested on day 8 or 9. The DCs were incubated with tumor lysate and KLH for 2 hr at 37°C. After certifying the absence of microorganisms and endotoxins, the patients received four DC vaccinations at two- to three-week intervals. Two patients received four DC vaccinations with means of 7.8 × 106 and 9 × 106 DCs at two- to three-week intervals. The DC vaccinations were well tolerated with no apparent side effects. After the vaccinations, the patients showed immunological responses with positive delayed-type hypersensitivity skin reaction and increasing autologous T cells stimulatory capacity to the DCs; however, the BM blast percentage of the patients did not improve. The results suggest that DCs are a feasible cellular therapy for relapsing AML after autologous SCT. J Clin Apheresis 19:66,70, 2004. © 2004 Wiley-Liss, Inc. [source] Evaluation of survival in Japanese stage IV melanoma patients treated with melanoma antigen-pulsed mature monocyte-derived dendritic cellsTHE JOURNAL OF DERMATOLOGY, Issue 12 2008Noriaki NAKAI No abstract is available for this article. [source] | ||||||||||