Virus-induced Systemic Vasculitides: New Therapeutic Approaches

The best therapeutic strategy in virus-induced vasculitides should take into account the etiology of the disease and be adapted to the pathogenesis. The combination of antiviral treatments and plasma exchanges has been proven effective in polyarteritis nodosa (PAN). In human immunodeficiency virus (HIV)-related vasculitis this strategy is also effective and does not jeopardize, like cytotoxic agents, the outcome of AIDS. In vasculitis related to HCV-associated cryoglobulinemia, plasma exchanges improve the outcome but the poor effectiveness of antiviral drugs is not able to favor, usually, a definite recovery of the patients and relapses are frequent

Meta-analytic estimation of measurement variability and assessment of its impact on decision-making: the case of perioperative haemoglobin concentration monitoring

Abstract Background As a part of a larger Health Technology Assessment (HTA), the measurement error of a device used to monitor the hemoglobin concentration of a patient undergoing surgery, as well as its decision consequences, were to be estimated from published data. Methods A Bayesian hierarchical model of measurement error, allowing the meta-analytic estimation of both central and dispersion parameters (under the assumption of normality of measurement errors) is proposed and applied to published data; the resulting potential decision errors are deduced from this estimation. The same method is used to assess the impact of an initial calibration. Results The posterior distributions are summarized as mean ± sd (credible interval). The fitted model exhibits a modest mean expected error (0.24 ± 0.73 (−1.23 1.59) g/dL) and a large variability (mean absolute expected error 1.18 ± 0.92 (0.05 3.36) g/dL). The initial calibration modifies the bias (−0.20 ± 0.87 (−1.99 1.49) g/dL), but the variability remains almost as large (mean absolute expected error 1.05 ± 0.87 (0.04 3.21) g/dL). This entails a potential decision error (“false positive” or “false negative”) for about one patient out of seven. Conclusions The proposed hierarchical model allows the estimation of the variability from published aggregates, and allows the modeling of the consequences of this variability in terms of decision errors. For the device under assessment, these potential decision errors are clinically problematic

Protective effect of A/H1N1 vaccination in immune-mediated disease—a prospectively controlled vaccination study

Objectives. To assess the 2009 influenza vaccine A/H1N1 on antibody response, side effects and disease activity in patients with immune-mediated diseases. Methods. Patients with RA, SpA, vasculitis (VAS) or CTD (n = 149) and healthy individuals (n = 40) received a single dose of adjuvanted A/H1N1 influenza vaccine. Sera were obtained before vaccination, and 3 weeks, 6 weeks and 6 months thereafter. A/H1N1 antibody titres were measured by haemagglutination inhibition (HAI) assay. Seroprotection was defined as specific antibody titre ≥ 1 : 40, seroconversion as 4-fold increase in antibody titre. Results. Titres increased significantly in patients and controls with a maximum at Week 3, declining to levels below protection at Month 6 (P < 0.001). Seroprotection was more frequently reached in SpA and CTD than in RA and VAS (80 and 82% and 57 and 47%, respectively). There was a significantly negative impact by MTX (P < 0.001), rituximab (P = 0.0031) and abatacept (P = 0.045). Other DMARDs, glucocorticoids and TNF blockers did not significantly suppress response (P = 0.06, 0.11 and 0.81, respectively). A linear decline in response was noted in patients with increasing age (P < 0.001). Disease reactivation possibly related to vaccination was suspected in 8/149 patients. No prolonged side effects or A/H1N1 infections were noted. Conclusions. The results show that vaccination response is a function of disease type, intensity and character of medication and age. A single injection of adjuvanted influenza vaccine is sufficient to protect a high percentage of patients. Therefore, differential vaccination recommendations might in the future reduce costs and increase vaccination acceptanc

Autoantibodies to Endothelial Cell Surface ATP Synthase, the Endogenous Receptor for Hsp60, Might Play a Pathogenic Role in Vasculatides

International audienceBACKGROUND: Heat shock protein (hsp) 60 that provides "danger signal" binds to the surface of resting endothelial cells (EC) but its receptor has not yet been characterized. In mitochondria, hsp60 specifically associates with adenosine triphosphate (ATP) synthase. We therefore examined the possible interaction between hsp60 and ATP synthase on EC surface. METHODOLOGY/PRINCIPAL FINDINGS: Using Far Western blot approach, co-immunoprecipitation studies and surface plasmon resonance analyses, we demonstrated that hsp60 binds to the β-subunit of ATP synthase. As a cell surface-expressed molecule, ATP synthase is potentially targeted by anti-EC-antibodies (AECAs) found in the sera of patients suffering vasculitides. Based on enzyme-linked immunosorbent assay and Western blotting techniques with F1-ATP synthase as substrate, we established the presence of anti-ATP synthase antibodies at higher frequency in patients with primary vasculitides (group I) compared with secondary vasculitides (group II). Anti-ATP synthase reactivity from group I patients was restricted to the β-subunit of ATP synthase, whereas those from group II was directed to the α-, β- and γ-subunits. Cell surface ATP synthase regulates intracellular pH (pHi). In low extracellular pH medium, we detected abnormal decreased of EC pHi in the presence of anti-ATP synthase antibodies, irrespective of their fine reactivities. Interestingly, soluble hsp60 abrogated the anti-ATP synthase-induced pHi down-regulation. CONCLUSIONS/SIGNIFICANCE: Our results indicate that ATP synthase is targeted by AECAs on the surface of EC that induce intracellular acidification. Such pathogenic effect in vasculitides can be modulated by hsp60 binding on ATP synthase which preserves ATP synthase activity

Identification of new autoantibody specificities directed at proteins involved in the transforming growth factor β pathway in patients with systemic sclerosis

International audienceABSTRACT: INTRODUCTION: Antinuclear antibodies (ANA), usually detected by indirect immunofluorescence on HEp-2 cells, are identified in 90% of patients with systemic sclerosis (SSc). Thus, approximately 10% of SSc patients have no routinely detectable autoantibodies, and for 20% to 40% of those with detectable ANA, the ANA do not have identified specificity (non-identified ANA). In this work, we aimed to identify new target autoantigens in SSc patients. METHODS: Using a proteomic approach combining 2-D electrophoresis and immunoblotting with HEp-2 cell total and enriched nuclear protein extracts as sources of autoantigens, we systematically analysed autoantibodies in SSc patients. Sera from 45 SSc patients were tested in 15 pools from groups of 3 patients with the same phenotype. A sera pool from 12 healthy individuals was used as a control. Proteins of interest were identified by mass spectrometry and analysed using Pathway Studio software. RESULTS: We identified 974 and 832 protein spots in HEp-2 cell total and enriched nuclear protein extracts, respectively. Interestingly, alpha-enolase was recognised by immunoglobulin-G (IgG) from all pools of patients in both extracts. Fourteen and 4 proteins were recognised by IgG from at least 75% of the 15 pools in total and enriched nuclear protein extracts, respectively, whereas 15 protein spots were specifically recognised by IgG from at least 4 of the 10 pools from patients with non-identified ANA. The IgG intensity for a number of antigens was higher in sera from patients than in those from healthy controls; these antigens included triosephosphate isomerase, superoxide dismutase mitochondrial precursor, heterogeneous nuclear ribonucleoprotein L and lamin A/C. In addition, peroxiredoxin-2, cofilin-1 and calreticulin were specifically recognised by sera from phenotypic subsets of patients with non-identified ANA. Interestingly, several identified target antigens were involved in the transforming growth factor-beta pathway. CONCLUSIONS: We identified several new target antigens shared among patients with SSc or specific to a given phenotype. The specification of new autoantibodies could help in understanding the pathophysiology of SSc. Moreover, these autoantibodies could represent new diagnostic and/or prognostic markers for SSc

Les 100 médicaments essentiels. Une approche de médecine interne = 100 essential drugs. An internal medicine approach

Déclaration d'intérêts : B. Grosbois : expert pour Actélion, Celgene, Octapharma, Shire. Recherche subventionnée par LFB, Janssen, Genzyme. L. Guillevin : conseiller scientifique Actélion, expert pour (et conférences rémunérées par) GSK, CSL, Roche. L. Guillevin estime cependant n'avoir pas de conflit d'intérêt concernant le présent travail. C. Le Jeunne : expert pour Roche, Sanofi, Novartis, BSM, UCB. Essais thérapeutiques en cours pour Bayer, Pfizer, BMS. P. Morlat : expert pour Gilead, ViiV Health Care, BMS, Abbott, MSD. Ph. Morlat estime cependant n'avoir pas de conflit d'intérêt concernant le présent travail. P. Arlet, O. Aumaitre, J. Cosserat, A. Kettaneh, C. Massot et M. Thomas : aucun conflit d'intérêt.International audiencePURPOSE: Up to 4600 drugs in about 15,000 pharmaceutical forms are available in France which may be a source of misuse with increased occurrence of side effects and costs. While the World Health Organization is encouraging each developed country to work out its own list of essential drugs. The list provided in 2008 by the French Office for the safety of health products has had so far limited impact on practice, so it became obvious to a group of internists to work out a "wise list" of 100 essential medicines covering 95% of the disorders observed in France. METHODS: In June 2011, 10 internists agreed to each provide a list of 100 essential medicines, according to individual experience. In December 2011, a meeting of the participants provided a list as initial consensus and mandated five among them to make proposals for those areas neglected by too many participants or in which needless dispersion of medicines was stated. After internet-facilitated exchanges, an additional list was validated in mild-January 2012. RESULTS: Fifty-four drugs were included in the list of initial consensus (including nine selected by all 10 participants), and 46 in the additional list. So the final "wise list" included 100 drugs. In June 2012, 56 of these drugs were available as generics. This list was compared to those lists set out by five countries in the European Union. CONCLUSION: Generating such a list is feasible. Undoubtedly still non-comprehensive, this list will benefit from the expertise of 14 general practitioners who are currently working out a similar list across France. The final list will be submitted for validation by the French associations of generalist teachers and Internists

Identification of target antigens of anti-endothelial cell and anti-vascular smooth muscle cell antibodies in patients with giant cell arteritis: a proteomic approach

International audienceABSTRACT: INTRODUCTION: Immunological studies of giant cell arteritis (GCA) suggest that a triggering antigen of unknown nature could generate a specific immune response. We thus decided to detect autoantibodies directed against endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) in the serum of GCA patients and to identify their target antigens. METHODS: Sera from 15 GCA patients were tested in 5 pools of 3 patients' sera and compared to a sera pool from 12 healthy controls (HCs). Serum immunoglobulin G (IgG) reactivity was analysed by 2-D electrophoresis and immunoblotting with antigens from human umbilical vein ECs (HUVECs) and mammary artery VSMCs. Target antigens were identified by mass spectrometry. RESULTS: Serum IgG from GCA patients recognised 162 ± 3 (mean ± SD) and 100 ± 17 (mean ± SD) protein spots from HUVECs and VSMCs, respectively, and that from HCs recognised 79 and 94 protein spots, respectively. In total, 30 spots from HUVECs and 19 from VSMCs were recognised by at least two-thirds and three-fifths, respectively, of the pools of sera from GCA patients and not by sera from HCs. Among identified proteins, we found vinculin, lamin A/C, voltage-dependent anion-selective channel protein 2, annexin V and other proteins involved in cell energy metabolism and key cellular pathways. Ingenuity pathway analysis revealed that most identified target antigens interacted with growth factor receptor-bound protein 2. CONCLUSIONS: IgG antibodies to proteins in the proteome of ECs and VSMCs are present in the sera of GCA patients and recognise cellular targets that play key roles in cell biology and maintenance of homeostasis. Their potential pathogenic role remains to be determined

Predictors of treatment resistance and relapse in antineutrophil cytoplasmic antibody-associated small-vessel vasculitis: Comparison of two independent cohorts

Predictors of treatment resistance and relapse have been identified in patients with antineutrophil cytoplasmic antibody (ANCA)–associated vasculitis in the Glomerular Disease Collaborative Network (GDCN) in the southeastern US. This study was undertaken to evaluate the applicability of those predictors in an independent cohort followed up by the French Vasculitis Study Group