Search results for "Tumor Necrosis Factors"
showing 10 items of 11 documents
Induction of the cytokine TWEAK and its receptor Fn14 in ischemic stroke.
2008
Stroke outcome is determined by delayed neuronal cell death and edema formation. TWEAK, a cytokine of the TNF superfamily, and its membrane receptor Fn14 promote ischemia-induced neuronal apoptosis and leakage of the blood-brain barrier. Both TWEAK and Fn14 are upregulated in experimental stroke models. In this study, we investigated whether TWEAK and Fn14 are upregulated in stroke patients. We measured serum concentrations of TWEAK in stroke patients and matched control subjects by ELISA. Expression of Fn14 in the brain was evaluated by real-time RT-PCR and immunohistochemistry. TWEAK serum concentrations were elevated in stroke patients. In autopsy samples, we found elevated mRNA levels o…
Technical advance: Soluble OX40 molecule mimics regulatory T cell modulatory activity on FCεRI-dependent mast cell degranulation
2011
ABSTRACT Tregs play a central role in modulating FcɛRI-dependent MC effector functions in the course of the allergic response. Cellular interaction depends on the constitutive expression of OX40 on Tregs and the OX40L counterpart on MCs. Study of OX40L signaling on MCs is hampered by the need of a highly purified molecule, which triggers OX40L specifically. We now report that sOX40 mimics the physiological activity of Treg interaction by binding to activated MCs. When treated with sOX40, activated MCs showed decreased degranulation and Ca++ influx, whereas PLC-γ2 phosphorylation remained unaffected. Once injected into experimental animals, sOX40 not only located within the endothelium but a…
JNK and AP-1 mediate apoptosis induced by bortezomib in HepG2 cells via FasL/caspase-8 and mitochondria-dependent pathways
2006
The proteasome inhibitor bortezomib is an efficacious apoptotic agent in many tumor cells. This paper shows that bortezomib induced apoptosis in human hepatoma HepG2 cells associated with many modifications in the expression of survival or death factors. Although bortezomib increased the level of the protective factors HSP70 and HSP27, the effects of the drug that favour cell death were predominant. These events include accumulation of c-Jun, phospho-c-Jun and p53; increase in FasL level with activation of caspase-8; changes related to members of Bcl-2 family with increase in the level of pro-apoptotic members and decrease in that of anti-apoptotic ones; dissipation of mitochondrial potenti…
Anandamide-induced apoptosis in Chang liver cells involves ceramide and JNK/AP-1 pathway
2006
In the present study we demonstrate that anandamide, the most important endogenous cannabinoid, markedly induced apoptosis in Chang liver cells, an immortalized non-tumor cell line derived from normal liver tissue, while it induced only modest effects in a number of hepatoma cell lines. The apoptotic effect was reduced by methyl-beta-cyclodextrin, a membrane cholesterol depletor, suggesting an interaction between anandamide and the membrane microdomains named lipid rafts. Anandamide effects were mediated by the production of ceramide, as demonstrated by experiments performed with the sphingomyelinase inhibitor, desipramine, or with the sphingomyelinase activator, melittin. This conclusion w…
Epithelial NEMO links innate immunity to chronic intestinal inflammation
2007
Deregulation of intestinal immune responses seems to have a principal function in the pathogenesis of inflammatory bowel disease(1-4). The gut epithelium is critically involved in the maintenance of intestinal immune homeostasis-acting as a physical barrier separating luminal bacteria and immune cells, and also expressing antimicrobial peptides(3,5,6). However, the molecular mechanisms that control this function of gut epithelial cells are poorly understood. Here we show that the transcription factor NF kappa B, a master regulator of pro-inflammatory responses(7,8), functions in gut epithelial cells to control epithelial integrity and the interaction between the mucosal immune system and gu…
Reduced circulating sTWEAK levels are associated with metabolic syndrome in elderly individuals at high cardiovascular risk
2014
BACKGROUND: The circulating soluble TNF-like weak inducer of apoptosis (sTWEAK) is a cytokine that modulates inflammatory and atherogenic reactions related to cardiometabolic risk. We investigated the association between sTWEAK levels and metabolic syndrome (MetS) and its components in older subjects at high cardiovascular risk. METHODS: Cross-sectional analysis of 452 non-diabetic individuals (men and women aged 55-80 years) at high cardiovascular risk. MetS was defined by AHA/NHLBI and IDF criteria. Logistic regression analyses were used to estimate odds ratios (ORs) for MetS and its components by tertiles of serum sTWEAK concentrations measured by ELISA. RESULTS: sTWEAK concentrations we…
Long-term anti-TNF therapy and the risk of serious infections in a cohort of patients with rheumatoid arthritis: Comparison of adalimumab, etanercept…
2012
Objective: To evaluate the risk of serious infections (SIs) in RA patients receiving anti-TNF therapy on the basis of the data included in the GISEA register. METHODS: The study involved 2769 adult patients with long-standing RA (mean age 53.2±13.4years; mean disease duration 9.0±8.3years) enrolled in the GISEA register, who had been treated for at least 6months with TNF inhibitors or had discontinued therapy due to SI: 837 (30%) treated with infliximab (IFN), 802 (29%) with adalimumab (ADA), and 1130 (41%) with etanercept (ETN). RESULTS: 176 patients had experienced at least one of the 226 Sis during the 9years of treatment with an anti-TNF agent, an overall incidence of 31.8/1000 patient-…
Mast cells counteract regulatory T-cell suppression through interleukin-6 and OX40/OX40L axis toward Th17-cell differentiation
2009
Abstract The development of inflammatory diseases implies inactivation of regulatory T (Treg) cells through mechanisms that still are largely unknown. Here we showed that mast cells (MCs), an early source of inflammatory mediators, are able to counteract Treg inhibition over effector T cells. To gain insight into the molecules involved in their interplay, we set up an in vitro system in which all 3 cellular components were put in contact. Reversal of Treg suppression required T cell–derived interleukin-6 (IL-6) and the OX40/OX40L axis. In the presence of activated MCs, concomitant abundance of IL-6 and paucity of Th1/Th2 cytokines skewed Tregs and effector T cells into IL-17–producing T cel…
CD4+CD25+ regulatory T cells suppress mast cell degranulation and allergic responses through OX40-OX40L interaction.
2008
T regulatory (Treg) cells play a role in the suppression of immune responses, thus serving to induce tolerance and control autoimmunity. Here, we explored whether Treg cells influence the immediate hypersensitivity response of mast cells (MCs). Treg cells directly inhibited the FcεRI-dependent MC degranulation through cell-cell contact involving OX40-OX40L interactions between Treg cells and MCs, respectively. When activated in the presence of Treg cells, MCs showed increased cyclic adenosine monophosphate (cAMP) concentrations and reduced Ca2+ influx, independently of phospholipase C (PLC)-γ2 or Ca2+ release from intracellular stores. Antagonism of cAMP in MCs reversed the inhibitory effec…