Dataset Information

Synovial fluid myeloid dendritic cells display important differences compared to monocyte-derived dendritic cells prepared in vitro.

ABSTRACT: The object of this study was to characterise synovial fluid dendritic cells (SFDCs) with regard to morphology, phenotype and responses to 1,25hydroxy-cholecalciferol (1,25D) and lipopolysaccharide (LPS), and to compare these characteristics with those of peripheral blood (PB) monocyte-derived DCs (MDDCs). SF was aspirated from knees with inflammatory effusions. PB samples were obtained contemporaneously. SFDCs were separated by flow cytometry. Morphology was determined on cytosmears. Expression of accessory molecules, cytokines and prostaglandin synthases mRNA was quantified by reverse transcription PCR. Analyses were performed on freshly prepared DCs and after incubation with 1,25D and LPS, separately and in combination. SFDCs and MDDCs displayed broadly similar morphology. Expression of accessory molecules, cytokines, cyclooxygenase-2 (COX-2) and prostaglandin E-synthase (PGES) was similar. SFDCs, but not MDDCs, expressed prostaglandin D-synthase (PGDS). PGDS was lost on incubation with SFDCs, but was induced by 1,25D in MDDCs. LPS in the presence or absence of 1,25D, induced interleukin 23 (IL23), IL1? and tumour necrosis factor-? in SFDCs and MDDCs, with SFDC showing stronger expression of these cytokines. 1,25D in combination with LPS induced PGES and enhanced LPS induction of IL6 in SFDCs and MDDCs. LPS reduced 1,25D-induced expression of PGDS in MDDCs. SFDCs and MDDCs display similar basal characteristics but differ in PGDS expression and responsiveness to LPS and 1,25D. MDDCs have limitations as a model of SFDCs which have differentiated in vivo.

SUBMITTER: Moghaddami M

PROVIDER: S-EPMC4232072 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Synovial fluid myeloid dendritic cells display important differences compared to monocyte-derived dendritic cells prepared in vitro.

Moghaddami Mahin M James Michael M Whittle Samuel L SL Cleland Leslie G LG

Clinical & translational immunology 20140808 8

The object of this study was to characterise synovial fluid dendritic cells (SFDCs) with regard to morphology, phenotype and responses to 1,25hydroxy-cholecalciferol (1,25D) and lipopolysaccharide (LPS), and to compare these characteristics with those of peripheral blood (PB) monocyte-derived DCs (MDDCs). SF was aspirated from knees with inflammatory effusions. PB samples were obtained contemporaneously. SFDCs were separated by flow cytometry. Morphology was determined on cytosmears. Expression ...[more]

PMID: 25505971

Similar Datasets

Project description:Recent advances reveal that metabolic reprogramming is required for adequate antiviral responses of dendritic cells (DCs) that possess the capacity to initiate innate and adaptive immune responses. Several reports indicate that Toll-like receptor (TLR) stimulation of DCs is accompanied by a rapid induction of glycolysis; however, the metabolic requirements of retinoic-acid inducible gene I (RIG-I)-like receptor (RLR) activation have not defined either in conventional DCs (cDCs) or in plasmacytoid DCs (pDCs) that are the major producers of type I interferons (IFN) upon viral infections. To sense viruses and trigger an early type I IFN response, pDCs rely on endosomal TLRs, whereas cDCs employ cytosolic RIG-I, which is constitutively present in their cytoplasm. We previously found that RIG-I is upregulated in pDCs upon endosomal TLR activation and contributes to the late phase of type I IFN responses. Here we report that TLR9-driven activation of human pDCs leads to a metabolic transition to glycolysis supporting the production of type I IFNs, whereas RIG-I-mediated antiviral responses of pDCs do not require glycolysis and rather rely on oxidative phosphorylation (OXPHOS) activity. In particular, TLR9-activated pDCs show increased extracellular acidification rate (ECAR), lactate production, and upregulation of key glycolytic genes indicating an elevation in glycolytic flux. Furthermore, administration of 2-deoxy-D-glucose (2-DG), an inhibitor of glycolysis, significantly impairs the TLR9-induced secretion of type I IFNs by human pDCs. In contrast, RIG-I stimulation of pDCs does not result in any alterations of ECAR, and type I IFN production is not inhibited but rather promoted by 2-DG treatment. Moreover, pDCs activated via TLR9 but not RIG-I in the presence of 2-DG are impaired in their capacity to prime allogeneic naïve CD8+ T cell proliferation. Interestingly, human monocyte-derived DCs (moDC) triggered via RIG-I show a commitment to glycolysis to promote type I IFN production and T cell priming in contrast to pDCs. Our findings reveal for the first time, that pDCs display a unique metabolic profile; TLR9-driven but not RIG-I-mediated activation of pDCs requires glycolytic reprogramming. Nevertheless, the metabolic signature of RIG-I-stimulated moDCs is characterized by glycolysis suggesting that RIG-I-induced metabolic alterations are rather cell type-specific and not receptor-specific.

Project description:Despite their distinct etiology, several lines of evidence suggest that innate immunity plays a pivotal role in both juvenile idiopathic arthritis (JIA) and septic arthritis (SA) pathophysiology. Indeed, monocytes and dendritic cells (DC) are involved in the first line of defense against pathogens and play a critical role in initiating and orchestrating the immune response. The aim of this study was to compare the number and phenotype of monocytes and DCs in peripheral blood (PB) and synovial fluid (SF) from patients with JIA and SA to identify specific cell subsets and activation markers associated with pathophysiological mechanisms and that could be used as biomarkers to discriminate both diseases. The proportion of intermediate and non-classical monocytes in the SF and PB, respectively, were significantly higher in JIA than in SA patients. In contrast the proportion of classical monocytes and their absolute numbers were higher in the SF from SA compared with JIA patients. Higher expression of CD64 on non-classical monocyte was observed in PB from SA compared with JIA patients. In SF, higher expression of CD64 on classical and intermediate monocyte as well as higher CD163 expression on intermediate monocytes was observed in SA compared with JIA patients. Moreover, whereas the number of conventional (cDC), plasmacytoid (pDC) and inflammatory (infDC) DCs was comparable between groups in PB, the number of CD141+ cDCs and CD123+ pDCs in the SF was significantly higher in JIA than in SA patients. CD14+ infDCs represented the major DC subset in the SF of both groups with potent activation assessed by high expression of HLA-DR and CD86 and significant up-regulation of HLA-DR expression in SA compared with JIA patients. Finally, higher activation of SF DC subsets was monitored in SA compared with JIA with significant up-regulation of CD86 and PDL2 expression on several DC subsets. Our results show the differential accumulation and activation of innate immune cells between septic and inflammatory arthritis. They strongly indicate that the relative high numbers of CD141+ cDC and CD123+ pDCs in SF are specific for JIA while the over-activation of DC and monocyte subsets is specific for SA.

Project description:BackgroundChronic, low-grade inflammation of the synovium (synovitis) is a hallmark of osteoarthritis (OA), thus understanding of OA immunobiology, mediated by immune effectors, is of importance. Specifically, monocytes/macrophages (MΦs) are known to be abundantly present in OA joints and involved in OA progression. However, different subsets of OA MΦs have not been investigated in detail, especially in terms of their relationship with patient-reported outcome measures (PROMs). We hypothesized that levels of synovial fluid (SF) MΦ subsets are indicative of joint function and quality of life in patients with OA, and can therefore serve as biomarkers and therapeutic targets for OA.MethodsIn this cohort study, synovial fluid leukocytes (SFLs, N = 86) and peripheral blood mononuclear cells (n = 53) from patients with knee OA were characterized. Soluble MΦ receptors and chemokine (sCD14, sCD163, CCL2, CX3CL1) levels were detected in SF using immunoassays. Linear models, adjusted for sex, age and body mass index, were used to determine associations between SF MΦs and soluble factors with PROMs (N = 83). Pearson correlation was calculated to determine correlation between MΦ subsets, T cells and soluble factors.ResultsSF MΦs were the most abundant SFLs. Within these, the double-positive CD14+CD16+-MΦ subset is enriched in knee OA SF compared to the circulation. Importantly, MΦ subset ratios correlated with PROMs, specially stiffness, function and quality of life. Interestingly, the SF CD14+CD16+-MΦ subset ratio correlated with SF chemokine (C-C motif) ligand 2 (CCL2) levels but not with levels of sCD163 or sCD14; we found no association between PROMs and either SF CCL2, sCD163, sCD14 or CX3CL1 (which was below detection levels). All SF MΦs displayed high levels of HLA-DR, suggesting an activated phenotype. Correlation between OA SF MΦ subsets and activated CD4+ T cell subsets suggests modulation of CD4+ T cell activation by MΦs.ConclusionSF MΦ subsets are associated with knee OA PROMs and display an activated phenotype, which may lead to modulation of CD4+ T cell activation. Knee OA SF MΦ subsets could serve as knee OA function biomarkers and as targets of novel therapeutics.

Dataset Information

Synovial fluid myeloid dendritic cells display important differences compared to monocyte-derived dendritic cells prepared in vitro.

Publications

Synovial fluid myeloid dendritic cells display important differences compared to monocyte-derived dendritic cells prepared in vitro.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets