3D) and Foxp3+ regulatory CD4+ T cells (Fig. 3E) was similar in both strains of mice, whereas at day 22 p.i., as compared with FasLfl/fl mice, the percentage of Foxp3− CD25+ activated CD4+ T cells was increased while the percentage of Foxp3+ regulatory CD4+ T cells was reduced in GFAP-Cre FasLfl/fl mice, respectively (Fig. 3D and E). Intraspinal CD4+ T cells from both mouse strains expressed Fas, as detected by flow cytometry (Fig. 3F), and, thus, they might be regulated by FasL+ cells. At day 22 p.i., the percentage of 7-aminoactinomycin

D (7-AAD)+ CD4+ T cells was significantly reduced in GFAP-Cre FasLfl/fl mice as compared with that in FasLfl/fl mice (Fig. 3G, *p < 0.05) suggesting that elimination of infiltrating T cells by apoptosis was impaired in GFAP-Cre FasLfl/fl mice in late stages of EAE. Annexin V staining was not used to detect CD4+ T-cell apoptosis in vivo because previous reports showed that annexin selleck chemical V did not selectively detect apoptotic T cells, since it also stained activated CD4+ T cells [24]. To examine the impact of astrocyte-specific FasL deletion on the expression of proinflammatory genes during EAE, quantitative real-time PCR for cytokines and chemokines

was performed on spinal cord tissue at day 15 p.i. and day 22 p.i. of EAE, respectively. At day 15 p.i., IFN-γ and IL-27 mRNA was significantly elevated in GFAP-Cre FasLfl/fl mice as compared to FasLfl/fl mice while mRNA levels of IL-17, TNF, IL-23, and GM-CSF did not differ between the two mouse strains (Fig. 4). In contrast, at day 22 p.i., mRNA levels

www.selleckchem.com/screening/chemical-library.html of all mediators, except for IL-23, were significantly upregulated in GFAP-Cre FasLfl/fl mice as compared mafosfamide with levels in FasLfl/fl mice, indicating an increased proinflammatory response in the spinal cord of GFAP-Cre FasLfl/fl mice at this late time point (Fig. 4). Interestingly, mRNA of IL-17, a main mediator of EAE, persisted at high levels in the spinal cord of GFAP-Cre FasLfl/fl mice up to day 22 p.i. Taken together, these results show that astrocytic deletion of FasL resulted in an increased transcription of important proinflammatory genes in the spinal cord which induce and contribute to severity of EAE. Twenty-four hours after coculture of FasLfl/fl CD4+ T cells with primary astrocytes isolated from the CNS of FasLfl/fl or GFAP-Cre FasLfl/fl mice, T-cell apoptosis induced by FasL-deficient astrocytes was compared to that induced by control astrocytes. In accordance with a previous report of Bechmann et al. [21], significantly lower numbers of T cells cocultured with FasL-deficient astrocytes underwent apoptosis as demonstrated by both annexin V binding and caspase staining (Fig. 5). Based on these findings, we conclude that, during EAE, astrocytic FasL-induced apoptotic elimination of T cells in the CNS of GFAP-Cre FasLfl/fl mice is significantly compromised as compared with that of control animals, resulting in a significantly enhanced disease activity.

RNA was reverse-transcribed with First Strand cDNA Synthesis kit (Roche Diagnostics, Mannheim, Germany) and quantified with primer pairs (Search-LC, Heidelberg, Germany) specific for IFN-γ or the housekeeping see more gene hypoxanthine guanine phosphoribosyl transferase (hprt) in a LightCycler 2.0 Real-Time PCR system (Roche Diagnostics). The signal of IFN-γ in each sample was normalized to that obtained for hprt. At the protein level, IFN-γ expression was determined by intracellular

staining with APC-conjugated XMG-1.2 mAb (BioLegend) after 4 h of PMA/ionomycine stimulation of total splenocytes or by using an IFN-γ capture assay kit (Miltenyi Biotec). NK cells were defined as NK1.1+CD3- by counterstaining for NK1.1 and CD3, and dead cells were excluded by propidium iodide (ICN, Eschwege, Germany). Survival analyses were made using the log-rank

test. For phenotyping and RT-PCR, means and standard deviations are shown in the diagrams. As the normality assumption of the data is not violated, we used Student’s t test for analyses of these data. We are indebted to D. J. Schendel for her ongoing support. Expert technical assistance by N. Hömberg, A. Geishauser and N. Dierkes is gratefully acknowledged. We thank J. Schulz for help in RT-PCR experiments and P. Reitmeir for statistical advice. This work includes parts of the doctoral theses of C.D.B., M.P., I.W. and C.A. The work was supported by grants from Deutsche Krebshilfe (107114

and Nivolumab 107128) and Wilhelm-Sander-Stiftung (2003.043.2) and SFB 685. Conflict of interest: The authors declare no financial or commercial conflict of interest. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available BCKDHB as submitted by the authors. “
“Anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis is an autoimmune disease in which the contributions of genetic, epigenetic and environmental factors to aetiology and pathogenesis are being unravelled. The ANCA immunoglobulin G targeting proteinase 3 and myeloperoxidase affects several neutrophil functions, usually to augment or dysregulate these, promoting a proinflammatory phenotype whereby neutrophils have enhanced capabilities of causing collateral damage to endothelial and other cells. In addition, B cells are intimately involved in pathogenesis as anti-B cell therapies are highly effective, but the manner of this involvement still needs to be delineated. Similarly, the T cell compartment is disturbed in ANCA vasculitis and numerous alterations in T cell subsets have been described, but recognition of a novel CD8+ T cell transcription signature which can predict likelihood of relapse in ANCA vasculitis indicates that more needs to be learnt about the influence of T cells in the disease process.

7D). Thus, in vivo infusion with DC-FcγRIIb could protect MRL/lpr mice from obvious nephritis injuries. Finally, in vivo administration of DC-FcγRIIb, before (4-wk-old) or after (10-wk-old) the onset of clinic lupus, was found to be able to significantly prolong the survival of MRL/lpr mice, whereas MRL/lpr mice receiving DC-GFP or DCs all died by 40 wk (Fig. 7E). Thus, in vivo administration of DC-FcγRIIb www.selleckchem.com/products/bmn-673.html could protect MRL/lpr mice from lupus progression, both preventively and therapeutically. SLE is a progressive systemic autoimmune disease, for which current therapy relies largely on long-term suppression of the immune system. We

here provide a short-term treatment regimen to attenuate lupus progression. Single infusion of DC-FcγRIIb, either before or after the onset of clinic lupus, into lupus-prone mice exerts a significant protection from lupus progression. The presence of large amounts of circulating IC in SLE may be potent stimulator for DCs. However, selleck inhibitor for DC-FcγRIIb, these IC might become potent inhibitor of DC maturation through binding to the preferentially expressed FcγRIIb. FcγRIIb-mediated negative signal contributes to the maintenance of immature/tolerogenic property of DCs. The consequence of this event results in suppression of antigen-specific

T-cell responses and thereby inhibition of B-cell responses, furthermore reducing the generation of autoreactive T cells and autoantibodies. It has been previously reported that decreased FcγRIIb expression is associated with the progression of lupus;

it would therefore make sense that artificial enhancement of the inhibitory FcγRIIb expression on some cell types could possibly provide an efficient approach for the treatment of lupus. In addition to the maintenance of DC tolerogenecity, IC also induce massive PGE2 production from DCs and more PGE2 from DC-FcγRIIb. PGE2 might play a protective role in autoimmune responses via directly inhibiting both CD4+ and CD8+ T-cell responses, inducing Foxp3+ Treg differentiation, suppressing B-cell activation and Ig production 28–32. Moreover, PGE2 Monoiodotyrosine may be also responsible for the inhibition of TLR-induced DC maturation because PGE2-triggered signal is involved in the downregulation of TLR4 expression 27. It is worth investigating whether PGE2 also contributes to inhibition of TLR7 and TLR9 expression, because natural activators of TLR9 and TLR7 can be found in the blood of lupus patients. FcγRIIb seems to be a redundant receptor to mediate PGE2 production, because FcγRIIb−/− DCs can also produce certain amount of PGE2 although much less than that produced by WT DCs in response to stimuli. We found that DCs express more FcγRIIa than FcγRIIb (Supporting Information Fig. 5), suggesting that other activating FcγRs might contribute to the production of PGE2 by IC. Once pretreated with IC and then triggered with TLR-ligands, FcγRIIb−/− DCs could secrete certain level of PGE2.