Search results for "Dendritic Cell"

2015

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 tol…

Exclusive Expression of MyD88 on Dendritic Cells Is Sufficient to Induce Protection against Experimental Leishmaniasis

2022

Treatment with an Allogeneic Leukemia-Derived Dendritic Cell Vaccine in AML Patients Shows MRD Conversion and Improved Survival

2021

Abstract Background. Persistence of measurable residual disease (MRD) is a poor prognostic factor and predicts relapse in acute myeloid leukemia (AML). In a phase I study, the allogeneic leukemia-derived dendritic cell vaccine, DCP-001, has shown safety and humoral and cellular immune responses (A.A. van de Loosdrecht, et al. Cancer Immunol. Immunother. 2018;67:1505). In the current phase II study, (Clintrials.gov: NCT03697707) we report on progress and evaluation of MRD conversion, as primary endpoint, relapse free and overall survival. Methods. AML-patients, ineligible at screening for HSCT, who are in first complete remission (CR1) but with MRD receive 4 biweekly doses of 25e6 or 50e6 ce…

Adjuvant effects of aluminium hydroxide-adsorbed allergens and allergoids – differences in vivo and in vitro

2014

Summary Allergen-specific immunotherapy (SIT) is a clinically effective therapy for immunoglobulin (Ig)E-mediated allergic diseases. To reduce the risk of IgE-mediated side effects, chemically modified allergoids have been introduced. Furthermore, adsorbance of allergens to aluminium hydroxide (alum) is widely used to enhance the immune response. The mechanisms behind the adjuvant effect of alum are still not completely understood. In the present study we analysed the effects of alum-adsorbed allergens and allergoids on their immunogenicity in vitro and in vivo and their ability to activate basophils of allergic donors. Human monocyte derived dendritic cells (DC) were incubated with native …

Hop-derived fraction rich in beta acids and prenylflavonoids regulates the inflammatory response in dendritic cells differently from quercetin: unvei…

2021

Dendritic cells (DCs) represent a heterogeneous family of immune cells that link innate and adaptive immunity and their activation is linked to metabolic changes that are essential to support their activity and function. Hence, targeting the metabolism of DCs represents an opportunity to modify the inflammatory and immune response. Among the natural matrices, Humulus lupulus (Hop) compounds have recently been shown to exhibit immunomodulatory and anti-inflammatory activity. This study aimed to evaluate the ability of specific Hop fractions to modulate DCs metabolism after stimulation with lipopolysaccharide (LPS) by an untargeted metabolomics approach and compare their effect with flavonol …

Production of interleukin-13 by human dendritic cells after stimulation with protein allergens is a key factor for induction of T helper 2 cytokines …

2003

Dendritic cells (DC) are able to induce not only T helper 1 (Th1) but also Th2 immune responses after stimulation with allergens. While DC-derived interleukin (IL)-12 and IL-18 are the key factors for the induction of Th1 cells, early signals being involved in Th2 differentiation are less well characterized so far. To analyse such early signals we used an antigen-specific setting with CD4+ T cells from atopic donors stimulated in the presence of autologous mature DC, which were pulsed with different allergen doses. The addition of increasing amounts of allergen during DC maturation with tumour necrosis factor-alpha, IL-1beta and prostaglandin E2 resulted in enhanced secretion of IL-6 and IL…

Gram-positive bacteria on grass pollen exhibit adjuvant activity inducing inflammatory T cell responses.

2011

BACKGROUND: Recently, it has been established that pollen grains contain Th2-enhancing activities besides allergens. OBJECTIVE: The aim of this study was to analyse whether pollen carry additional adjuvant factors like microbes and what immunological effects they may exert. METHODS: Timothy pollen grains were collected and disseminated on agar plates, and the growing microorganisms were cultivated and defined. Furthermore, the immunologic effects of microbial products on DC and T cell responses were analysed. RESULTS: A complex mixture of bacteria and moulds was detected on grass pollen. Besides Gram-negative bacteria that are known to favour Th1-directed immune responses, moulds were ident…

IgG Fc sialylation is regulated during the germinal center reaction following immunization with different adjuvants

2020

Background: Effector functions of IgG Abs are regulated by their Fc N-glycosylation pattern. IgG Fc glycans that lack galactose and terminal sialic acid residues correlate with the severity of inflammatory (auto)immune disorders and have also been linked to protection against viral infection and discussed in the context of vaccine-induced protection. In contrast, sialylated IgG Abs have shown immunosuppressive effects.Objective: We sought to investigate IgG glycosylation programming during the germinal center (GC) reaction following immunization of mice with a foreign protein antigen and different adjuvants.Methods: Mice were analyzed for GC T-cell, B-cell, and plasma cell responses, as wel…

Compartmentalized production of CCL17 in vivo: strong inducibility in peripheral dendritic cells contrasts selective absence from the spleen.

2003

Dendritic cells (DCs)(*) fulfill an important regulatory function at the interface of the innate and adaptive immune system. The thymus and activation-regulated chemokine (TARC/CCL17) is produced by DCs and facilitates the attraction of activated T cells. Using a fluorescence-based in vivo reporter system, we show that CCL17 expression in mice is found in activated Langerhans cells and mature DCs located in various lymphoid and nonlymphoid organs, and is up-regulated after stimulation with Toll-like receptor ligands. DCs expressing CCL17 belong to the CD11b(+)CD8(-)Dec205(+) DC subset, including the myeloid-related DCs located in the subepithelial dome of Peyer's patches. CCL17-deficient mi…

The RNA binding protein tristetraprolin influences the activation state of murine dendritic cells

2010

Abstract Dendritic cells (DCs) serve to maintain peripheral tolerance under steady state conditions. Upon triggering by activation signals they initiate strong immune responses. The activation of DCs is accompanied by a rapid upregulation of proinflammatory cytokines, which were shown in other cell types to be regulated by mechanisms at the transcriptional and posttranscriptional level. Tristetraprolin (TTP), an important RNA binding protein, is involved in the regulation of mRNA stability of such cytokines. In this study we analyzed the significance of TTP for mouse DCs, which were derived from TTP −/− and WT bone marrow progenitor cells (BM-DCs). Unstimulated BM-DCs of TTP −/− mice expres…