59 research outputs found
COMPARATIVE STUDY OF TWO HELIX ASPERSA EXTRACTS ON TUMOR CELL LINES (HUT-78 AND SEAX) PROLIFERATION AND MMP-9 SECRETION
Objective: Despite the progress in cancer research, current therapies are ineffective and cause many adverse effects. The discovery of new natural anti-tumor agents that can act on multiple mechanisms of growth and tumor invasion with minor side effects and which can be safe for patients. Therefore, we sought new natural products from an invertebrate organism belonging to the phylum of mollusks: a land snail, Helix aspersa. This study was aimed to evaluate the cytotoxic activity of two extracts prepared from Helix aspersa, on two cutaneous T cell lymphoma cell line (HUT-78 and SeAx). Their effect on MMP-9 expression was also tested.Methods: We prepared from the snail Helix aspersa: an aqueous (AE) and a hydroalcoholic extracts (HAE). We have evaluated the concentration of total proteins and total phenols in these extracts. The percentage of cell mortality was evaluated after incubating the cell lines with the two extracts at different concentrations, by using trypan blue exclusion method. Finally, the tumor cells expression of metalloproteinase MMP-9 was examined by zymography analysis.Results: We have found that 1 mg/ml of AE contains (4.53ñ0.48 mg) of total proteins and (2.44ñ0.11 mg) GAE g-1of phenols. 1 mg/ml of HAE contains (1.83ñ0.23 mg) of total proteins and (2.81ñ0.16 mg) GAE g-1 of phenols. On one hand, both extracts exerted a toxic effect on these tumor cells. Indeed, aqueous extract induced 44.09 % mortality in HUT-78 and 31.47 % mortality in SeAx tumor cell line with 50 Ôg/ml. While, the hydroalcoholic extract induced 29.90 % in HUT-78 and 25 % in SeAx. On the other hand, the result showed no changes of MMP-9 expression.Conclusion: Helix aspersa's extracts had a toxic effect on cutaneous T cell lymphoma (CTCL), but did not inhibit the production of the protease by these two cell lines in culture
NET Formation in Bullous Pemphigoid Patients With Relapse Is Modulated by IL-17 and IL-23 Interplay
Background: DNA extracellular traps (ETs), released by neutrophils (NETs), or eosinophils (EETs), play a pathogenic role in several autoimmune disorders. However, to date, NETs have never been investigated in bullous pemphigoid (BP) with respect to clinical and immunological activities, both at baseline and at time of relapse which have been characterized with specific IL-17 and IL-23 patterns.Objective: We sought to assess whether ETs were associated with BP as well as the relative contribution of IL-17 axis cytokines to NET induction.Methods: Skin biopsy specimens were obtained from 11 patients with BP. Immuno-detection of neutrophils and eosinophils combined to DNA staining allowed us to investigate the in-situ presence of NETs and EETs using confocal scanning microscopy. NETs release was evaluated ex vivo by stimulating polymorphonuclear cells from BP patients with BP biological fluids in presence of IL-17A and IL-23 or of glucocorticoids.Results: At baseline, ETs were observed in BP lesions at the site of dermal-epidermal cleavage. Despite an important infiltrate of eosinophils, ETs were essentially associated with neutrophils in situ and were not related to BP clinical activity at diagnosis. In situ observation of NETs was associated in 6 among 8 patients with serum capacity of NET induction. Notably both blister fluid and sera from BP patients at diagnosis and at time of relapse could induce NET formation ex vivo. In contrast, a longitudinal investigation showed a decrease of NET formation with time of treatment in patients undergoing remission. Mimicking relapse, complementation of sera from BP patients with ongoing remission with either IL-17A or IL-23 increased NET formation. Conversely, IL-17A inhibited NET formation induced by serum from BP patients with relapse supplemented or not with IL-23. Finally, glucocorticoids also inhibited NET formation ex vivo in BP.Conclusion: NET formation is an associated phenomenon with BP. Furthermore, we showed that IL-23 favored NET formation, whereas the effects of IL-17A are environment dependent. Indeed, IL-17A displayed a protective effect on NET formation when associated with IL-23, showing for the first-time differential effects of these two cytokines in BP
Paraneoplastic Syndromes and Thymic Malignancies: An Examination of the International Thymic Malignancy Interest Group Retrospective Database
Introduction
Thymic epithelial tumors (TETs) are associated with paraneoplastic autoimmune (PN/AI) syndromes. Myasthenia gravis is the most common PN/AI syndrome associated with TETs.
Methods
The International Thymic Malignancy Interest Group (ITMIG) retrospective database was examined to determine (i) baseline and treatment characteristics associated with PN/AI syndromes and (ii) the prognostic role of PN/AI syndromes for patients with TETs. The competing risks model was used to estimate cumulative incidence of recurrence (CIR) and the Kaplan-Meier method was used to calculate overall survival (OS). A Cox proportional hazards model was used for multivariate analysis.
Results
6670 patients with known PN/AI syndrome status were identified from 1951-2012. PN/AI syndromes were associated with younger age, female sex, type B1 thymoma, earlier stage, and an increased rate of total thymectomy and complete resection status. There was a statistically significant lower CIR in the PN/AI (+) group compared to the PN/AI (-) group (10-year 17.3% vs. 21.2%, respectively, p=0.0003). The OS was improved in the PN/AI (+) group compared to the PN/AI (-) group (HR 0.63, 95% CI 0.54-0.74, P<0.0001, median OS 21.6 years versus 17.0 years, respectively). However, in the multivariate model for recurrence-free survival and OS, PN/AI syndrome was not an independent prognostic factor.
Discussion
Previously, there has been mixed data regarding the prognostic role of PN/AI syndromes for patients with TETs. Here, using the largest dataset in the world for TETs, PN/AI syndromes were associated with favorable features (i.e. earlier stage, complete resection status) but were not an independent prognostic factor for TETs
Meeting Report of the Pathogenesis of Pemphigus and Pemphigoid Meeting in Munich, September 2016
Autoimmune blistering diseases are a heterogeneous group of about a dozen complex disorders that are characterized by intraepidermal (pemphigus) and subepidermal blistering (pemphigoid diseases and dermatitis herpetiformis). The Pathogenesis of Pemphigus and Pemphigoid Meeting, organized by the Departments of Dermatology in Lubeck and Marburg and the Institute of Anatomy and Cell Biology, Munich, was held in September 2016 in Munich. The meeting brought together basic scientists and clinicians from all continents dedicating their work to autoimmune blistering diseases. Considerable advances have been made in describing incidences and prevalences of these diseases and linking comorbidities with autoantibody reactivities and clinical variants, for example, dipeptidyl peptidase-IV inhibitor-associated noninflammatory bullous pemphigoid. Although new entities are still being described, diagnosis of most autoimmune blistering diseases can now be achieved using standardized and widely available serological test systems. Various experimental mouse models of pemphigus and pemphigoid disease are increasingly being used to understand mechanisms of central and peripheral tolerance and to evaluate more specific treatment approaches for these disorders, such as molecules that target autoreactive T and B cells and anti-inflammatory mediators, that is, dimethyl fumarate, phosphodiesterase 4, and leukotriene B4 inhibitors in pemphigoid disorders, and chimeric antigen receptor T cells in pemphigus. Very recent experimental data about the immunopathology and the determinants of autoantibody formation and keratinocyte susceptibility in pemphigus were discussed. With regard to cellular mechanisms leading to the loss of cell-cell adhesion, new ideas were shared in the field of signal transduction. Major steps were taken to put the various partly contradictory and controversial findings about the effects of pemphigus autoantibodies and other inflammatory mediators into perspective and broaden our view of the complex pathophysiology of this disease. Finally, two investigator-initiated multicenter trials highlighted doxycycline and dapsone as valuable medications in the treatment of bullous pemphigoid.Non peer reviewe
Regulation des activites phospholipasiques A2 dans les cellules thyroiediennes en culture : effets de la dexamethasone et des esters de phorbol sur la synthese et/ou l'activite des lipocortines
SIGLECNRS T Bordereau / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
Bullous Pemphigoid: A Review of its Diagnosis, Associations and Treatment
International audienceBullous pemphigoid (BP) is the most common autoimmune subepidermal blistering disease in Western countries, and typically affects the elderly. BP is immunologically characterized by tissue-bound and circulating autoantibodies directed against either the BP antigen 180 (BP180, or BPAG2) or the BP antigen 230 (BP230, or BPAG1e), or even both, which are components of hemidesmosomes involved in the dermal-epidermal cohesion. Risk factors for BP include old age, neurologic diseases (dementia, Parkinson's disease, cerebrovascular disease), and some particular drugs, including loop diuretics, spironolactone and neuroleptics. The spectrum of clinical presentations is extremely broad. Clinically, BP is an intensely pruritic erythematous eruption with widespread blister formation. In the early stages, or in atypical, non-bullous variants of the disease, only excoriated, eczematous or urticarial lesions (either localized or generalized) are present. The diagnosis of BP relies on immunopathologic findings, especially based on both direct and indirect immunofluorescence microscopy observations, as well as on anti-BP180/BP230 enzyme-linked immunosorbent assays (ELISAs). BP is usually a chronic disease, with spontaneous exacerbations and remissions, which may be accompanied by significant morbidity. In the past decade, potent topical corticosteroids have emerged as an effective and safe first-line treatment for BP, but their long-term feasibility is still controversial. Newer therapeutic agents targeting molecules involved in the inflammatory cascade associated with BP represent future alternatives to classical immunosuppressant drugs for maintenance therapy
Autoantibodies Associated With Connective Tissue Diseases: What Meaning for Clinicians?
Connective tissue diseases (CTDs) such as systemic lupus erythematosus, systemic sclerosis, myositis, Sjögrenâs syndrome, and rheumatoid arthritis are systemic diseases which are often associated with a challenge in diagnosis. Autoantibodies (AAbs) can be detected in these diseases and help clinicians in their diagnosis. Actually, pathophysiology of these diseases is associated with the presence of antinuclear antibodies. In the last decades, many new antibodies were discovered, but their implication in pathogenesis of CTDs remains unclear. Furthermore, the classification of these AAbs is nowadays misused, as their targets can be localized outside of the nuclear compartment. Interestingly, in most cases, each antibody is associated with a specific phenotype in CTDs and therefore help in better defining either the disease subtypes or diseases activity and outcome. Because of recent progresses in their detection and in the comprehension of their pathogenesis implication in CTD-associated antibodies, clinicians should pay attention to the presence of these different AAbs to improve patientâs management. In this review, we propose to focus on the different phenotypes and features associated with each autoantibody used in clinical practice in those CTDs
The elastin peptides-mediated induction of pro-collagenase-1 production by human fibroblasts involves activation of MEK/ERK pathway via PKA- and PI 3 K-dependent signaling
International audienceElastin peptides, such as kappa-elastin (kE), bind to the elastin receptor at the cell surface of human dermal fibroblasts and stimulate collagenase-1 expression at the gene and protein levels. Using specific inhibitors and phosphospecific antibodies, we show here that the binding of elastin peptides to their receptor activates the extracellular signal-regulated kinase (ERK) pathway; this activation is essential for the induction of pro-collagenase-1 production. Moreover, protein kinase A (PKA) and phosphatidylinositol 3-kinase (PI(3)K) signaling were found to participate in ERK activation. Concomitantly, we demonstrate that stimulation by elastin peptides leads to enhanced DNA binding of activator protein-1 (AP-1). Our data indicate that the up-regulation of collagenase-1 following treatment of fibroblasts with elastin peptides results from a cross-talk between PKA, PI(3)K and the ERK signaling pathways and that this regulation is accompanied by activation of AP-1 transcription factors
Anti-Type VII Collagen Antibodies Are Identified in a Subpopulation of Bullous Pemphigoid Patients With Relapse
Bullous pemphigoid (BP) is an autoimmune bullous skin disease characterized by anti-BP180 and anti-BP230 autoantibodies (AAbs). Mucous membrane involvement is an uncommon clinical feature of BP which may evoke epidermolysis bullosa acquisita, another skin autoimmune disease characterized by anti-type VII collagen AAbs. We therefore evaluated the presence of anti-type VII collagen AAbs in the serum of BP patients with and without mucosal lesions at time of diagnosis and under therapy. Anti-BP180, anti-BP230, and anti-type VII collagen AAbs were measured by ELISA in the serum of unselected patients fulfilling clinical and histo/immunopathological BP criteria at baseline (nâ=â71) and at time of relapse (nâ=â24). At baseline, anti-type VII collagen AAbs were detected in 2 out of 24 patients with BP presenting with mucosal involvement, but not in patients without mucosal lesions (nâ=â47). At the time of relapse, 10 out of 24 BP patients either displayed a significant induction or increase of concentrations of anti-type VII collagen AAbs (Pâ<â0.01), independently of mucosal involvement. Those 10 relapsing BP patients were also characterized by a sustained high concentration of anti-BP180 AAb, whereas the serum anti-BP230 AAb concentrations did not vary in BP patients with relapse according to the presence of anti-type VII collagen AAbs. Thus, our study showed that anti-type VII collagen along with anti-BP180 AAbs detection stratified BP patients at time of relapse, illustrating a still dysregulated immune response that could reflect a potential epitope spreading mechanism in those BP patients
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