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Wolfgang L Gross

Publications and source records attributed to Wolfgang L Gross.

At least 19 recordsLinked to original sources
PubMed2006

EULAR recommendations for conducting clinical studies and/or clinical trials in systemic vasculitis: focus on anti-neutrophil cytoplasm antibody-associated vasculitis.

OBJECTIVES: To develop the European League Against Rheumatism (EULAR) recommendations for conducting clinical studies and/or clinical trials in systemic vasculitis. METHODS: An expert consensus group was formed consisting of rheumatologists, nephrologists and specialists in internal medicine representing five European countries and the USA, a clinical epidemiologist and representatives from regulatory agencies. Using an evidence-based and expert opinion-based approach in accordance with the standardised EULAR operating procedures, the group identified nine topics for a systematic literature search through a modified Delphi technique. On the basis of research questions posed by the group, recommendations were derived for conducting clinical studies and/or clinical trials in systemic vasculitis. RESULTS: Based on the results of the literature research, the expert committee concluded that sufficient evidence to formulate guidelines on conducting clinical trials was available only for anti-neutrophil cytoplasm antibody-associated vasculitides (AAV). It was therefore decided to focus the recommendations on these diseases. Recommendations for conducting clinical trials in AAV were elaborated and are presented in this summary document. It was decided to consider vasculitis-specific issues rather than general issues of trial methodology. The recommendations deal with the following areas related to clinical studies of vasculitis: definitions of disease, activity states, outcome measures, eligibility criteria, trial design including relevant end points, and biomarkers. A number of aspects of trial methodology were deemed important for future research. CONCLUSIONS: On the basis of expert opinion, recommendations for conducting clinical trials in AAV were formulated. Furthermore, the expert committee identified a strong need for well-designed research in non-AAV systemic vasculitides.

Antibodies↗
PubMed2006

[Rheumatology -- Part 3. Research news concerning epidemiology, diagnosis, and therapy of primary systemic vasculitides].

Antineutrophil cytoplasmic autoantibody-(ANCA-)associated vasculitides, immune complex-mediated vasculitides and granulomatous arteritides of unknown etiology belong to the group of primary systemic vasculitides. Numerous in vitro and in vivo studies have underscored the role of ANCA in the pathogenesis of ANCA-associated vasculitides (Wegener's granulomatosis, microscopic polyangiitis, Churg-Strauss syndrome) in the meantime. Whereas the pathogenicity of myeloperoxidase (MPO) ANCA has been supported by data from various animal models in the past, the in vivo pathogenicity of proteinase 3 (PR3) ANCA has been demonstrated in an animal model only recently. Other studies showed an altered T-cell response in Wegener's granulomatosis. Hepatitis C virus-(HCV-)associated cryoglobulinemic vasculitis is mediated by immune complexes. Recent data suggest that the HCV core particles concentrated in the cryoprecipitate apparently play a role in the interaction of cryoglobulin and endothelial cells and neutrophil granulocytes. Data from the European Vasculitis Study Group (EUVAS) demonstrate the efficacy of azathioprine in maintaining remission in ANCA-associated vasculitides on the basis of large patient numbers. Biologicals play an increasing role in the treatment of refractory vasculitis.

Adrenal Cortex Hormones↗
PubMed2006

On the Wegener granulomatosis associated region on chromosome 6p21.3.

BACKGROUND: Wegener granulomatosis (WG) belongs to the heterogeneous group of systemic vasculitides. The multifactorial pathophysiology of WG is supposedly caused by yet unknown environmental influence(s) on the basis of genetic predisposition. The presence of anti-neutrophil cytoplasmic antibodies (ANCA) in the plasma of patients and genetic involvement of the human leukocyte antigen system reflect an autoimmune background of the disease. Strong associations were revealed with WG by markers located in the major histocompatibility complex class II (MHC II) region in the vicinity of human leukocyte antigen (HLA)-DPB1 and the retinoid X receptor B (RXRB) loci. In order to define the involvement of the 6p21.3 region in WG in more detail this previous population-based association study was expanded here to the respective 3.6 megabase encompassing this region on chromosome 6. The RXRB gene was analysed as well as a splice-site variation of the butyrophilin-like (BTNL2) gene which is also located within the respective region. The latter polymorphism has been evaluated here as it appears as a HLA independent susceptibility factor in another granulomatous disorder, sarcoidosis. METHODS: 150-180 German WG patients and a corresponding cohort of healthy controls (n = 100-261) were used in a two-step study. A panel of 94 microsatellites was designed for the initial step using a DNA pooling approach. Markers with significantly differing allele frequencies between patient and control pools were individually genotyped. The RXRB gene was analysed for single strand conformation polymorphisms (SSCP) and restriction fragment length polymorphisms (RFLP). The splice-site polymorphism in the BTNL2 gene was also investigated by RFLP analysis. RESULTS: A previously investigated microsatellite (#1.0.3.7, Santa Cruz genome browser (UCSC) May 2004 Freeze localisation: chr6:31257596-34999883), which was used as a positive control, remained associated throughout the whole two-step approach. Yet, no additional evidence for association of other microsatellite markers was found in the entire investigated region. Analysis of the RXRB gene located in the WG associated region revealed associations of two variations (rs10548957 pallelic = 0.02 and rs6531 pallelic = 5.20 x 10-5, OR = 1.88). Several alleles of markers located between HLA-DPB1, SNP rs6531 and microsatellite 1.0.3.7 showed linkage disequilibrium with r2 values exceeding 0.10. Significant differences were not demonstrable for the sarcoidosis associated splice-site variation (rs2076530 pallelic = 0.80) in our WG cohort. CONCLUSION: Since a microsatellite flanking the RXRB gene and two intragenic polymorphisms are associated significantly with WG on chromosome 6p21.3, further investigations should be focussed on extensive fine-mapping in this region by densely mapping with additional markers such as SNPs. This strategy may reveal even deeper insights into the genetic contributions of the respective region for the pathogenesis of WG.

Butyrophilins↗
PubMed2006

[Rheumatology-part 2. Research news concerning pathogenesis, epidemiology, diagnosis, and therapy of connective tissue disease].

Due to the partial elucidation of the immunopathogenesis of chronic inflammatory diseases during the last years, clinical rheumatology has made a rapid development, which by the consequent use of immunomodulatory therapies including recombinant proteins (biologicals) led to a significantly ameliorated prognosis of these diseases. On this basis, new research projects are continuously performed in the fields of pathogenesis, new drug development, outcome and therapy studies. New developments of imaging techniques and serologic testing facilitate a better classification and definition of disease activity and remission criteria. The current state of research in the field of collagen vascular diseases with its clinical consequences is reviewed in this article on the basis of the most recent data available.

Biological Products↗
PubMed2006

Wegener autoantigen induces maturation of dendritic cells and licenses them for Th1 priming via the protease-activated receptor-2 pathway.

Autoantibodies to proteinase 3 (PR3) are involved in the pathogenesis of autoimmune-mediated vasculitis in Wegener granulomatosis (WG). To address the question how the autoantigen PR3 becomes a target of adaptive immunity, we investigated the effect of PR3 on immature dendritic cells (iDCs) in patients with WG, healthy blood donors, and patients with Crohn disease (CD), another granulomatous disease. PR3 induces phenotypic and functional maturation of a fraction of blood monocyte-derived iDCs. PR3-treated DCs express high levels of CD83, a DC-restricted marker of maturation, CD80 and CD86, and HLA-DR. Furthermore, the DCs become fully competent antigen-presenting cells and can induce stimulation of PR3-specific CD4(+) T cells, which produce IFN-gamma. PR3-maturated DCs derived from WG patients induce a higher IFN-gamma response of PR3-specific CD4(+) T cells compared with patients with CD and healthy controls. The maturation of DCs mediated through PR3 was inhibited by a serine protease inhibitor, by antibodies directed against the protease-activated receptor-2 (PAR-2), and by inhibition of phospholipase C, suggesting that the interactions of PR3 with PAR-2 are involved in the induction of DC maturation. Wegener autoantigen interacts with a "gateway" receptor (PAR-2) on iDCs in vitro triggering their maturation and licenses them for a T helper 1 (Th1)-type response potentially favoring granuloma formation in WG.

Adult↗
PubMed2006

A case of destructive Wegener's granulomatosis complicated by cytomegalovirus infection.

BACKGROUND: A 63-year-old man with a 4-year history of Wegener's granulomatosis presented with hemoptysis, palatal ulceration and sensorimotor polyneuropathy. INVESTIGATIONS: Physical examination, serologic testing, proteinase 3 enzyme-linked immunosorbent assay, IgG and IgM specific to Epstein-Barr virus enzyme-linked immunosorbent assay, MRI of the middle face, an ear, nose and throat consultation, immunohistochemical staining of an esophageal sample obtained from esophagogastroduodenoscopy, polymerase chain reaction of cytomegalovirus (CMV) DNA from esophageal and blood samples, and measurement of pp65 early antigen. DIAGNOSIS: Wegener's granulomatosis with progressive palatal ulceration and osseous destruction complicated by CMV-related esophagitis during induction treatment. MANAGEMENT: Induction treatment with cyclophosphamide pulse therapy was discontinued and antiviral therapy with ganciclovir was started. Cyclophosphamide pulse therapy was later reintroduced, but there was subsequent CMV reactivation, and, therefore, cyclophosphamide pulse therapy was suspended again and ganciclovir and intravenous immunoglobulin were started. After control of CMV, cyclophosphamide pulse therapy was reinitiated. Prolonged immunosuppressive therapy controlled disease activity, without CMV reactivation.

Antiviral Agents↗
PubMed2006

Advances in the therapy of Wegener's granulomatosis.

PURPOSE OF REVIEW: In the past, recommendations for the treatment of Wegener's granulomatosis were primarily based on findings reported from open-label clinical trials. Results from several randomized controlled trials in patients with Wegener's granulomatosis and other antineutrophil cytoplasm antibody-associated vasculitides have recently been reported that have a great impact on patient care. RECENT FINDINGS: In view of the considerable toxicity of cyclophosphamide, strategies to limit exposure to it have recently been evaluated. The replacement of cyclophosphamide by azathioprine after the successful induction of remission has been demonstrated not to increase the rate of relapse compared with continued cyclophosphamide. In patients with early antineutrophil cytoplasm antibody-associated vasculitides without critical organ manifestations low-dose methotrexate can replace cyclophosphamide for induction treatment with similar remission rates. As the early discontinuation of immunosuppressive treatment is associated with unacceptably high relapse rates, however, treatment for the maintenance of remission is mandatory. Besides azathioprine, leflunomide and methotrexate were efficacious in preventing relapses in Wegener's granulomatosis. Data on anti-cytokine therapy in Wegener's granulomatosis are controversial, possibly related to differences in study design. Open-label clinical studies suggest a beneficial effect of infliximab in addition to standard therapy in refractory Wegener's granulomatosis. In contrast, a recent randomized controlled trial showed that etanercept in addition to standard therapy, with the subsequent tapering of standard medications, is not effective for the maintenance of remission. SUMMARY: Despite recent progress, the prevention of relapses and treatment of refractory cases remain the greatest challenges in the treatment of Wegener's granulomatosis.

Antibodies, Monoclonal↗
PubMed2005

Stable incidence of primary systemic vasculitides over five years: results from the German vasculitis register.

OBJECTIVE: To register all newly diagnosed patients with primary systemic vasculitides (PSV) in a large region in northern Germany. METHODS: Between January 1, 1998 and December 31, 2002 all newly diagnosed cases of PSV were identified in a large mixed rural/urban northern German region consisting of 2,777,275 habitants in a population-based prospective study. The following sources were used: departments of all hospitals, including their outpatient clinics; all departments of pathology; and the reference immunologic labs serving the catchment area. RESULTS: During 5 years, 642 PSV patients were identified. The incidence rates for all PSV were between 40 and 54 cases per 1 million and per year. People at age 50 years and older had a 3-5-fold higher risk of developing PSV compared with those younger than 50 years. The incidence rates of antineutrophil cytoplasmic antibody (ANCA)-associated PSV (Wegener's granulomatosis [WG], microscopic polyangiitis [MPA], Churg-Strauss syndrome [CSS]) were between 9.5 and 16/million/year. WG occured 2-3 times more frequently than MPA or CSS. CONCLUSION: Results of a population-based vasculitis register over 5 years for the incidence of PSV among 2.78 million habitants in northern Germany revealed a stable incidence for all PSV. Compared with other European studies coming from small regions or referral centers, the incidence rates for ANCA-associated PSV were the same as in Norway, lower than those in United Kingdom, but higher than those in Spain.

Adult↗
PubMed2005

Association study with Wegener granulomatosis of the human phospholipase Cgamma2 gene.

BACKGROUND: Wegener Granulomatosis (WG) is a multifactorial disease of yet unknown aetiology characterized by granulomata of the respiratory tract and systemic necrotizing vasculitis. Analyses of candidate genes revealed several associations, e.g. with alpha(1)-antitrypsin, proteinase 3 and with the HLA-DPB1 locus. A mutation in the abnormal limb mutant 5 (ALI5) mouse in the region coding for the hydrophobic ridge loop 3 (HRL3) of the phospholipaseCgamma2 (PLCgamma-2) gene, corresponding to human PLCgamma-2 exon 27, leads to acute and chronic inflammation and granulomatosis. For that reason, we screened exons 11, 12 and 13 coding for the hydrophobic ridge loop 1 and 2 (HRL1 and 2, respectively) and exon 27 of the PLCgamma-2 protein by single strand conformation polymorphism (SSCP), sequencing and PCR/ restriction fragment length polymorphism (RFLP) analyses. In addition, we screened indirectly for disease association via 4 microsatellites with pooled DNA in the PLCgamma-2 gene. RESULTS: Although a few polymorphisms in these distinct exons were observed, significant differences in allele frequencies were not identified between WG patients and respective controls. In addition, the microsatellite analyses did not reveal a significant difference between our patient and control cohort. CONCLUSION: This report does not reveal any hints for an involvement of the PLCgamma-2 gene in the pathogenesis of WG in our case-control study.

Alleles↗
PubMed2005

Randomized trial of cyclophosphamide versus methotrexate for induction of remission in early systemic antineutrophil cytoplasmic antibody-associated vasculitis.

OBJECTIVE: Standard therapy for antineutrophil cytoplasmic antibody-associated systemic vasculitis (AASV) with cyclophosphamide (CYC) and prednisolone is limited by toxicity. This unblinded, prospective, randomized, controlled trial was undertaken to determine whether methotrexate (MTX) could replace CYC in the early treatment of AASV. METHODS: Patients with newly diagnosed AASV, with serum creatinine levels <150 mumoles/liter, and without critical organ manifestations of disease were randomized to receive either standard oral CYC, 2 mg/kg/day or oral MTX, 20-25 mg/week; both groups received the same prednisolone regimen. All drug treatments were gradually tapered and withdrawn by 12 months. Followup continued to 18 months. The primary end point was the remission rate at 6 months (noninferiority testing). RESULTS: One hundred patients were recruited from 26 European centers; 51 patients were randomized to the MTX group and 49 to the CYC group. At 6 months, the remission rate in patients treated with MTX (89.8%) was not inferior to that in patients treated with CYC (93.5%) (P = 0.041). In the MTX group, remission was delayed among patients with more extensive disease (P = 0.04) or pulmonary involvement (P = 0.03). Relapse rates at 18 months were 69.5% in the MTX group and 46.5% in the CYC group; the median time from remission to relapse was 13 months and 15 months, respectively (P = 0.023, log rank test). Two patients from each group died. Adverse events (mean 0.87 episodes/patient) included leukopenia, which was less frequent in the MTX versus the CYC group (P = 0.012), and liver dysfunction, which was more frequent in the MTX group (P = 0.036). CONCLUSION: MTX can replace CYC for initial treatment of early AASV. The MTX regimen used in the present study was less effective for induction of remission in patients with extensive disease and pulmonary involvement and was associated with more relapses than the CYC regimen after termination of treatment. The high relapse rates in both treatment arms support the practice of continuation of immunosuppressive treatment beyond 12 months.

Adult↗
PubMed2005

The PTPN22 620W allele is a risk factor for Wegener's granulomatosis.

OBJECTIVE: Analyses of families with multiple autoimmune disorders have revealed a functional polymorphism, 620W, in the intracellular tyrosine phosphatase gene PTPN22 as a predisposing factor for type 1 diabetes, seropositive rheumatoid arthritis, systemic lupus erythematosus, and Hashimoto thyroiditis, and the presence of the PTPN22 protein appears to herald the development of autoantibodies in these disorders. This study therefore examined whether the functionally relevant PTPN22 polymorphism is associated with Wegener's granulomatosis (WG). METHODS: A population-based study was performed for the PTPN22 polymorphism in 199 patients with WG and in 399 healthy individuals. The R620W variation was investigated by simple restriction fragment-length polymorphism analysis. RESULTS: The PTPN22 620W allele frequency was significantly increased in antineutrophil cytoplasmic antibody (ANCA)-positive WG patients compared with healthy controls (P < 0.001). The association was particularly striking in patients with kidney, lung, eye, and peripheral nervous system involvement (i.e., those with generalized WG). CONCLUSION: The PTPN22 620W allele appears to be involved in the pathogenesis of WG, and ANCA positivity seems to be the hallmark.

Alleles↗
PubMed2005

Complex genetics of Wegener granulomatosis.

Wegener granulomatosis (WG) belongs to a heterogeneous group of systemic anti-neutrophil cytoplasmatic antibody (ANCA) associated vasculitides (AASV). WG is characterized by necrotizing granulomatous inflammation of the upper and lower respiratory tract, glomerulonephritis and vasculitis. As a multifactorial model disease, WG is hallmarked by the presence of specific ANCA-subtypes directed against a defined antigen. WG is more predominant among Caucasians and the genetic predisposition appears quite complex. Here, we provide a brief overview concerning genetic factors in the pathogenesis of WG and discuss intricacies of molecular genetic approaches.

Antibodies, Antineutrophil Cytoplasmic↗