Unlike for Human Monocytes after LPS Activation, Release of TNF-α by THP-1 Cells Is Produced by a TACE Catalytically Different from Constitutive TACE

Tumor necrosis factor-alpha (TNF-α) is a pro-inflammatory cytokine today identified as a key mediator of several chronic inflammatory diseases. TNF-α, initially synthesized as a membrane-anchored precursor (pro-TNF-α), is processed by proteolytic cleavage to generate the secreted mature form. TNF-α converting enzyme (TACE) is currently the first and single protease described as responsible for the inducible release of soluble TNF-α.Here, we demonstrated the presence on THP-1 cells as on human monocytes of a constitutive proteolytical activity able to cleave pro-TNF-α. Revelation of the cell surface TACE protein expression confirmed that the observed catalytic activity is due to TACE. However, further studies using effective and innovative TNF-α inhibitors, as well as a highly selective TACE inhibitor, support the presence of a catalytically different sheddase activity on LPS activated THP-1 cells. It appears that this catalytically different TACE protease activity might have a significant contribution to TNF-α release in LPS activated THP-1 cells, by contrast to human monocytes where the TACE activity remains catalytically unchanged even after LPS activation.On the surface of LPS activated THP-1 cells we identified a releasing TNF-α activity, catalytically different from the sheddase activity observed on human monocytes from healthy donors. This catalytically-modified TACE activity is different from the constitutive shedding activity and appears only upon stimulation by LPS

Quantification of Trace Metalloids and Metals in Airborne Particles Applying Dynamic Reaction Cell Inductively Coupled Plasma Mass Spectrometry

International audienc

Speciation of lead in ambient air dust combining individual particle analysis by ESEM-EDS, micro-Raman, micro-PIXE and bulk analysis by ICP-MS and selective chemical extractions

In order to determine the speciation of lead in ambient air dust, a combination of two complementary levels of investigation is used. The first one consists in a quantitative bulk analysis of the samples by applying selective chemical extractions followed by ICP-MS analysis. The second one is an individual particle analysis done by ESEM-EDS, micro-PIXE and micro-Raman. This paper presents the results from initial studies aiming to demonstrate the relevance of our methodology. Primary information about the main physico-chemical species of lead found in ambient air particulate matter, collected in the vicinity of a lead and zinc smelter, are given

Au-del\ue0 de l'arabe standard. Moyen arabe et arabe mixe dans les sources m\ue9di\ue9vales, modernes et contemporaines

Il volume presenta un insieme di contributi di autori di fama internazionale, che riguardano principalmente il medio arabo e l'arabo misto nella documentazione di epoca pre-moderna e contemporanea. La documentazione medievale e moderna \ue8 principalemnte suddivisa per confessione religiosa di origine del documento o per genere letterario, per cui si troveranno articoli riguardanti il giudeo-arabo, il medio arabo cristiano o documenti della letteratura epica o popolare. Per quanto riguarda la documentazione contemporanea i contributi presenti nel volume si sono principalmente dedicati alla riflessione dell'uso dell'arabo nei moderni mezzi di comunicazione e nel web: socialnetworks, chatrooms, e-mail, telegiornali etc..

Leachability and leaching patterns from aluminium-based water treatment residual used as media in laboratory-scale engineered wetlands

Concept and purpose Virtually all water treatment facilities worldwide generate an enormous amount of water treatment residual (WTR) solids for which environmentally-friendly end-use options are continually being sought as opposed to their landfilling. Aluminium-based WTR (Al-WTR) can offer huge benefits particularly for phosphorus (P) removal and biofilm attachment when used as media in engineered wetlands. However, potential environmental risks that may arise from the leaching out of its constituents must be properly evaluated before such reuse can be assured. This paper presents results of an assessment carried out to monitor and examine the leachability and leaching patterns of the constituents of an Al-WTR used as media in laboratory scale engineered wetland systems. Main features, materials and methods Al-WTR was used as media in four different configurations of laboratory scale engineered wetland systems treating agricultural wastewater. Selected metal levels were determined in the Al-WTR prior to being used while levels of total and dissolved concentration for the metals were monitored in the influent and effluent samples. The increase or decrease of these metals in the used Al-WTR and their potential for leaching were determined. Leached metal levels in the effluents were compared with relevant environmental quality standards to ascertain if they pose considerable risks. Results Aluminium, arsenic, iron, lead, and manganese were leached into the treated effluent, but aluminium exhibited the least leaching potential relative to the initial content in the fresh Al-WTR. Levels of P increased from 0.13 mg-P/g (fresh Al-WTR) to 33.9 mg-P/g – 40.6 mg-P/g (used Al-WTR). Dissolved levels of lead and arsenic (except on one instance) were below the prescribed limits for discharge. However, total and dissolved levels of aluminium were in most cases above the prescribed limits for discharge, especially at the beginning of the experiments. Conclusions, recommendations and perspectives Overall, the study indicate that when Al-WTR is beneficially reused for enhanced P removal in engineered wetlands as opposed to landfilling it, the leaching out of aluminium into the treated effluent beyond the prescribed limits of 0.2mg/l may be a potential problem. However, since the results obtained indicate that most of the aluminium leached out are associated with solids, a post-treatment unit which can further reduce the level of aluminium in the treated effluent by filtering out the solids could serve to mitigate this. Notwithstanding, the use of Al-WTR as a media in engineered wetlands can serve to greatly enhance the removal of P from wastewaters and also serve as support material for biofilm attachment.Other funderEnvironmental Protection Agenc

Proteinase 3 is an IL-32 binding protein

IL-32, a recently discovered proinflammatory cytokine with four isoforms, induces IL-1β, TNF-α, IL-6, and chemokines. Here, we used ligand (IL-32α) affinity chromatography in an attempt to isolate an IL-32α soluble receptor or binding protein. Recombinant IL-32α was covalently immobilized on agarose, and preparations of concentrated crude human urinary proteins were applied for chromatographic separation. A specific 30-kDa protein eluted from the column during acid washing and was identified by mass spectrometry as proteinase 3 (PR3) and confirmed by N-terminal microsequencing. PR3, a neutrophil granule serine protease, exists in a soluble or membrane form and is the major autoantigen for autoantibodies in the systemic vasculitic disease, Wegener's granulomatosis. The affinity of IL-32α to PR3 was determined by surface plasmon resonance. The dissociation constants were 2.65 ± 0.4 nM for urinary PR3 and 1.2 ± 0.05 nM for neutrophil-derived PR3. However, irreversible inactivation of PR3 enzymatic activity did not significantly change binding to the cytokine. Nevertheless, limited cleavage of IL-32 yielded products consistent with PR3 enzyme activity. Moreover, after limited cleavage by PR3, IL-32α was more active than intact IL-32α in inducing macrophage inflammatory protein-2 in mouse macrophages and IL-8 in human peripheral blood mononuclear cells. We suggest that PR3 is a specific IL-32α binding protein, independent of its enzymatic activity. However, limited cleavage of IL-32α by PR3 enhances activities of the cytokine. Therefore, specific inhibition of PR3 activity to process IL-32 or neutralization of IL-32 by inactive PR3 or its fragments may reduce the consequences of IL-32 in immune regulated diseases