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International audience; Renal ischaemia reperfusion (I/R) triggers a cascade of events including oxidative stress, apoptotic body and microparticle (MP) formation as well as an acute inflammatory process that may contribute to organ failure. Macrophages are recruited to phagocytose cell debris and MPs. The tyrosine kinase receptor MerTK is a major player in the phagocytosis process. Experimental models of renal I/R events are of major importance for identifying I/R key players and for elaborating novel therapeutical approaches. A major aim of our study was to investigate possible involvement of MerTK in renal I/R. We performed our study on both natural mutant rats for MerTK (referred to as RCS) and on wild type rats referred to as WT. I/R was established by of bilateral clamping of the renal pedicles for 30′ followed by three days of reperfusion. Plasma samples were analysed for creatinine, aspartate aminotransferase (ASAT), lactate dehydrogenase (LDH), kidney injury molecule -1 (KIM-1), and neutrophil gelatinase-associated lipocalin (NGAL) levels and for MPs. Kidney tissue damage and CD68-positive cell requirement were analysed by histochemistry. monocyte chemoattractant protein-1 (MCP-1), myeloperoxidase (MPO), inducible nitric oxide synthase (iNOS), and histone 3A (H3A) levels in kidney tissue lysates were analysed by western blotting. The phagocytic activity of blood-isolated monocytes collected from RCS or WT towards annexin-V positive bodies derived from cultured renal cell was assessed by fluorescence-activated single cell sorting (FACS) and confocal microscopy analyses. The renal I/R model for RCS rat described for the first time here paves the way for further investigations of MerTK-dependent events in renal tissue injury and repair mechanisms.

BackgroundSchnitzler syndrome (SchS) is a rare autoinflammatory disease characterized by urticarial exanthema, bone and joint alterations, fever and monoclonal IgM gammopathy. Overactivation of the interleukin(IL)-1 system is reported, even though the exact pathophysiological pathways remain unknown.ObjectiveTo determine ex vivo cytokine profiles of Peripheral Blood Mononuclear Cells (PBMCs) from SchS patients prior to treatment and after initiation of anti-IL-1 therapy (anakinra). The sera cytokine profile was studied in parallel.MethodsWe collected blood samples from thirty-six untreated or treated SchS. PBMCs were cultured with and without LPS or anti-CD3/CD28. Cytokine levels were evaluated in serum and cell culture supernatants using Luminex technology.ResultsSpontaneous TNFα, IL-6, IL-1β, IL-1α, and IL-1RA release by PBMCs of SchS patients were higher than in controls. LPS-stimulation further induced the secretion of these cytokines. In contrast, after T-cell stimulation, TNFα, IL-10, IFNγ, IL-17A, and IL-4 production decreased in SchS patients compared to healthy controls, but less in treated patients. Whereas IL-1β serum level was not detected in most sera, IL-6, IL-10, and TNFα serum levels were higher in patients with SchS and IFNγ and IL-4 levels were lower. Of note, IL-6 decreased after treatment in SchS (p = 0.04).ConclusionOur data strengthen the hypothesis of myeloid inflammation in SchS, mediated in particular by IL-1β, TNFα, and IL-6, associated with overproduction of the inhibitors IL-1RA and IL-10. In contrast, we observed a loss of Th1, Th2, and Th17 cell functionalities that tends to be reversed by anakinra.

International audience; Recent studies suggest that psoriasis may be more severe in patients with nonalcoholic fatty liver disease, particularly in those with the inflammatory stage of steatohepatitis [nonalcoholic steatohepatitis (NASH)]. Herein, we investigated the impact of diet-induced steatohepatitis on the severity of imiquimod-induced psoriasiform dermatitis. Mice fed with a high-fat diet developed steatohepatitis reminiscent of human NASH with ballooning hepatocytes and significant liver fibrosis. Mice with steatohepatitis also displayed moderate cutaneous inflammation characterized by erythema, dermalinfiltrates of CD45(+) leukocytes, and a local production of IL-17A. Moreover, steatohepatitis was associated with an epidermal activation of caspase-1 and cutaneous overexpression of IL-1 beta. Imiquimod-induced psoriasiform dermatitis was exacerbated in mice with steatohepatitis as compared to animals fed with a standard diet. Scale formation and acanthosis were aggravated, in correlation with increased IL-17A and IL-22 expression in inflamed skins. Finally, intradermal injection of IL-17A in standard diet-fed mice recapitulated the cutaneous pathology of mice with steatohepatitis. The results show that high-fat diet induced steatohepatitis aggravates the inflammation in psoriasiform dermatitis, via the cutaneous production of IL-17A. In agreement with clinical data, this description of a novel extrahepatic manifestation of NASH should sensitize dermatologists to the screening and the management of fatty liver in psoriatic patients.

In psoriasis, a specific cytokine network has been described to play a central role in the pathophysiology of the disease. Anti-cytokine therapeutic approaches have been largely developed and TNFα constitutes the main target. Adalimumab is a human anti-TNFα monoclonal antibody that has been reported to demonstrate clinical efficacy and safety, resulting in reversal of epidermal hyperplasia and cutaneous inflammation. We aimed to analyse changes in the skin inflammatory transcriptomic profile in psoriatic patients during adalimumab therapy. In addition, the circulating cytokine profile was analysed to define systemic inflammation. Eighteen patients with chronic plaque psoriasis were treated with adalimumab. After four and 16 weeks, clinical efficacy was assessed using PASI and DLQI, and skin mRNA profiles were determined and circulating cytokines quantified. We identified a rapid effect of adalimumab therapy on a large array of Th17 cytokines of the skin, which may account for the modification of keratinocyte expression profile and clinical response. In contrast, analysis of serum cytokine concentrations was uninformative, confirming the need for characterization of local cytokines in skin lesions. Finally, in non-responders, local cytokine expression was shown to be unchanged. We show that TNFα inhibition in psoriasis patients treated with adalimumab has a broad effect on the expression profile of cytokines and keratinocyte markers of skin inflammation, which may account for its clinical efficacy.

Pancreatic acinar cells are major targets of IL-22. Our aim is to study early plasma levels of IL-22, of pro- and anti-inflammatory cytokines in acute pancreatitis, and their association with severity or necrosis infection.Consecutive patients admitted to the Department of Hepato-Gastroenterology at Poitiers University of Medicine Hospital (France) with a diagnosis of AP were prospectively enrolled. Plasma concentrations of IL-22, IL-6, IL-8, IL-1 α, IL-1β, TNF- α, IFN-γ, IL-17A, IL-10, IL-1ra and IL-4 were assessed by multiple immunoassay at the admission time. A thoracoabdominal contrast-enhanced CT scan was performed at day 2.Sixty-two patients were included; 13 patients (21%) had a severe acute pancreatitis, 5 patients (8%) developed necrosis infection and 29 patients (47%) had pleural effusion. Plasma levels of IL-22 were high in AP (135 ± 31 vs 4.2 ± 1.8 pg/ml for controls, p0.05), but did not correlate with the severity of the disease, whereas IL-6, IL-10 and IL-1ra where enhanced in patients with severe acute pancreatitis and with pleural effusion. Patients who further developed necrosis infection had higher levels of IL-1ra at admission (p = 0.0004).In acute pancreatitis, high plasma levels of IL-22 are observed, regardless the severity of the disease. In contrast, severe forms were associated with increased levels of IL-6, IL-10 and IL-1ra. The beneficial or deleterious role of IL-22 in AP remains to be further studied.

Introduction Un reseau cytokinique complexe a ete decrit dans les lesions cutanees psoriasiques et illustre le role central des cytokines pro-inflammatoires telles que l’IL-23, l’IL-22, l’IL-17, l’IL-1, l’oncostatine M et le TNFα, produites par les cellules immunitaires infiltrees. Recemment, nous avons montre que l’association d’IL-1α, IL-17A, IL-22, OSM et TNFα agit de facon synergique sur les keratinocytes en augmentant l’expression de molecules liees a l’immunite innee et a l’inflammation, telles que des chimiokines et des peptides antimicrobiens, et en inhibant leur programme de differenciation. Ceci genere un modele in vitro d’inflammation cutanee mimant certaines caracteristiques du psoriasis. Nous avons demontre que cette combinaison de cytokines constitue une signature moleculaire des lesions cutanees psoriasiques. En parallele, plusieurs approches therapeutiques anti-cytokine ont ete developpees et le TNFα constitue une cible de choix. Parmi ces traitements, l’adalimumab est une IgG1 monoclonale anti-TNFα entierement humaine qui diminue l’inflammation cutanee et le score de severite clinique d’au moins 75 % chez environ 80 % des patients. Notre objectif etait d’analyser la modification du profil transcriptomique cutane et les concentrations des cytokines circulantes chez les patients psoriasiques pendant le traitement par l’adalimumab. Materiel et methodes Les patients psoriasiques ont ete traites par l’adalimumab. Au bout de 4 et 16 semaines, l’efficacite clinique de la therapie a ete evaluee par les mesures de PASI et de DLQI. Les profils transcriptomiques cutanes avant et apres traitement ont ete determines par RT-PCR quantitative et les cytokines circulantes mesurees par immuno-analyse multiplexe. Resultats Nous observons un effet clair et rapide du traitement par l’adalimumab sur l’expression des cytokines « Th17 », de l’IL-1 et de l’oncostatine M, expliquant les modifications d’expression genique par les keratinocytes (BD2, S100A7, CXCL8, CK10) et la reponse clinique. Une persistance de l’expression des cytokines et de leurs cibles keratinocytaires est egalement observee dans certaines lesions residuelles. En revanche, les concentrations seriques de cytokines sont peu correlees a l’evolution clinique et aux profils d’expression cutanes, ce qui confirme la necessite d’une caracterisation locale des cytokines dans les lesions cutanees. Fait interessant, en plus du maintien de l’expression locale des cytokines chez les patients non repondeurs, un profil cytokinique initial chez les non-repondeurs pourrait suggerer l’identification possible de marqueurs predictifs de resistance/sensibilite au traitement par l’adalimumab. Discussion Nos donnees montrent que le ciblage du TNFα dans le psoriasis a un effet tres large sur le profil d’expression des cytokines Th17 et des marqueurs de l’inflammation de la peau, ce qui explique son efficacite clinique.

International audience

In order to clarify the inflammatory mechanism underlying familial Mediterranean fever (FMF), we aimed to evaluate the ex vivo cytokine profile of FMF patients during acute attacks and attack-free periods, and compare it with that of healthy controls. The study included 34 FMF patients, of whom 9 were studied during attack and remission and 24 healthy controls. Cytokine levels were evaluated by Luminex technology in serum and supernatants of PBMC (Peripheral Blood Mononuclear Cells) cultures with and without 24h stimulation of monocytes by LPS and T lymphocytes by anti-CD3/CD28 beads. Levels of IL-6 and TNF-α were higher in unstimulated and LPS-stimulated PBMC supernatants of FMF patients in crises compared to controls. In response to LPS stimulation, higher levels of IL-1β and IL-1α were found in PBMC supernatants of patients during crises compared to those in remission and to controls. IFN-γ and IL-4 levels were the lowest in unstimulated and anti-CD3/CD28 stimulated PBMCs supernatants of patients during crises compared to remission and controls. The Th17 cytokines IL-17 and IL-22 were respectively higher in anti-CD3/CD28 stimulated PBMC supernatants of FMF patients during and between crises compared to controls. Amongst cytokines tested in serum, only IL-6 and TNFα were enhanced in FMF patients. The ex vivo study represents an interesting approach to evaluate cytokines' involvement in FMF. Our results suggest an ongoing subclinical inflammation and define an elevated inflammatory cytokine signature, distinctly for M694V homozygous patients. The absence of spontaneous IL-1β release by PBMCs reflects no constitutive activation of the inflammasome in FMF physiopathology.

Objective: Soluble forms of interleukin-6 (IL-6) receptors are known to modulate biological activities of IL-6. The purpose of the study was to measure circulating levels of IL-6, sIL-6R and sgp130 in patients undergoing coronary artery bypass grafting with cardiopulmonary bypass (CPB group) or without CPB (non-CPB group). Methods: The CPB group included 19 patients and the non-CPB group 12 patients. Sera levels of IL-6, sIL-6R and sgp130 were measured by specific ELISA at the beginning of the operation (T0, 15 min before skin incision) and 6 h later (T1). Results: IL-6 sera levels were respectively 9 ^ 20 pg/ml (mean ^ SD) and 13 ^ 19 pg/ml at T0 and reached 340 ^ 250 pg/ml and 965 ^ 1060 pg/ml at T1 in CPB and non-CPB groups, indicating a significant increase from T0 to T1, but no differences between the two groups. When compared to T0 values, sgp130 levels decreased in both groups (respectively 105 ^ 37 and 115 ^ 35 ng/ml at T0 for CPB and non-CPB groups, and 72 ^ 25 and 84 ^ 29 ng/ml at T1) while we are not able to detect differences between the groups. Whatever the group or the time, sIL-6R concentrations remained unchanged. Conclusions: We showed that the increase of IL-6 after artery bypass grafting was similar between patients operated with CPB or without CPB. We conclude that the main inductor of IL-6 release is linked to surgical trauma rather than a reaction to CPB. Since it is known that gp130 inhibits IL-6-biological activities, we suggest that the decrease of sgp130 sera levels could further enhance the inflammatory effects of IL-6 in cardiac surgery. q 2000 Elsevier Science B.V. All rights reserved.

Erdheim-Chester disease (ECD) is a rare non-Langerhans systemic histiocytosis of unknown origin. ECD is characterized by bilateral and symmetric sclerosis of the metaphyseal regions of the long bones and infiltration in other organs. Histopathologically, ECD is characterized by a mononuclear infiltrate of foamy histiocytes.

Objective A new class of autoinflammatory syndromes called NLRP12-associated disorders (NLRP12AD) has been associated with mutations in NLRP12. Conflicting data on the putative role of NLRP12 in interleukin-1β (IL-1β) signaling have been found in in vitro analyses. This prospective study was undertaken to assess the secretion of IL-1β and 3 IL-1β–induced cytokines (IL-1 receptor antagonist [IL-1Ra], IL-6, and tumor necrosis factor α [TNFα]) in patients' peripheral blood mononuclear cells (PBMCs) cultured ex vivo and to evaluate the patients' response to IL-1Ra (anakinra), a major drug used in the treatment of autoinflammatory disorders. Methods Patients' disease manifestations and cytokine measurements were recorded before anakinra treatment was started, during 14 months of therapy, and after discontinuation of anakinra treatment. Results Spontaneous secretion of IL-1β by patients' PBMCs was found to be dramatically increased (80–175 fold) compared to healthy controls. Consistent with these findings, anakinra initially led to a marked clinical improvement and to a rapid near-normalization of IL-1β secretion. However, a progressive clinical relapse occurred secondarily, associated with an increase in TNFα secretion, persistent elevated levels of IL-1Ra and IL-6, and a reactivation of IL-1β secretion. Anakinra was discontinued after 14 months of therapy. Conclusion Our findings provide in vivo evidence of the crucial role of IL-1β in the pathophysiology of NLRP12AD. This is the first time anakinra has been used to treat this disorder. This study provides new insights into the mechanisms underlying resistance to anti–IL-1 therapy observed in a few patients with autoinflammatory syndromes. Our data also point to the potential of ex vivo cytokine measurements as predictors of response to treatment.

Summary Interleukin (IL)-22 is a T cell-derived cytokine that has been reported recently to induce cutaneous inflammation in an experimental murine model of psoriasis, and to induce in vitro an inflammatory-like phenotype. In the present study, we assessed the presence of IL-22 and the IL-22 receptor 1 (IL-22R1) in skin lesions, skin-derived T cells, as well as IL-22 levels in sera from patients with psoriasis. IL-22R1 and IL-10R2 transcripts are expressed at a similar level in psoriatic and healthy skin. In contrast, IL-22 mRNA expression was up-regulated in psoriatic skin lesions compared to normal skin, whereas IL-22 mRNA levels in peripheral blood mononuclear cells from psoriatic patients and normal subjects were similar. Circulating IL-22 levels were significantly higher in psoriatic patients than in normal subjects. T cells isolated from psoriatic skin produced higher levels of IL-22 in comparison to peripheral T cells isolated from the same patients. IL-10 was expressed at similar levels in skin biopsies and peripheral blood mononuclear cells of psoriatic patients and normal subjects. Finally, we show here that supernatants of lesional psoriatic skin-infiltrating T cells induce an inflammatory response by normal human epidermal keratinocytes, resembling that observed in psoriatic lesions. Taken together, the results reported in this study indicate that IL-22 is a cytokine produced by skin-infiltrating lymphocytes that is potentially involved in initiation and/or maintenance of the pathogenesis of psoriasis.

Familial Mediterranean fever (FMF) is an autosomal recessive autoinflammatory disorder affecting mainly Jews, Armenians, Turks and Arabs. Recently, several pro- and anti-inflammatory cytokines have been studied in sera of Armenian and Turkish FMF patients during and in between crises. However, the information were limited and contradictory.