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Ulrich Specks

Publications and source records attributed to Ulrich Specks.

At least 19 recordsLinked to original sources
PubMed2006

Functional significance of Asn-linked glycosylation of proteinase 3 for enzymatic activity, processing, targeting, and recognition by anti-neutrophil cytoplasmic antibodies.

Proteinase 3 (PR3) is a neutral serine protease stored in neutrophil granules. It has substantial sequence homology with elastase, cathepsin G and azurocidin. PR3 is the target antigen for autoantibodies (ANCA) in Wegener's granulomatosis, a necrotizing vasculitis syndrome. ANCA have been implicated in the pathogenesis of this disease. PR3 has two potential Asn-linked glycosylation sites. This study was designed to determine the occupancy of these glycosylation sites, and to evaluate their effect on enzymatic function, intracellular processing, targeting to granules and recognition by ANCA. We found that glycosylation occurs at both sites in native neutrophil PR3 and in wild type recombinant PR3 (rPR3) expressed in HMC-1 cells. Using glycosylation deficient rPR3 mutants we found that glycosylation at Asn-147, but not at Asn-102, is critical for thermal stability, and for optimal hydrolytic activity of PR3. Efficient amino-terminal proteolytic processing of rPR3 is dependent on glycosylation at Asn-102. Targeting to granules is not dependent on glycosylation, but unglycosylated rPR3 gets secreted preferentially into media supernatants. Finally, a capture ELISA for ANCA detection, using rPR3 glycosylation variants as target antigens, reveals that in about 20% of patients, epitope recognition by ANCA is affected by the glycosylation status of PR3.

Amino Acid Sequence↗
PubMed2006

Melanoma antigen A4 is expressed in non-small cell lung cancers and promotes apoptosis.

A variety of melanoma antigen A (MAGE-A) genes are commonly detected in non-small cell lung cancers. Their biological function is not well characterized but may involve the regulation of apoptosis and cell cycle progression. We hypothesized that MAGE-A4 is involved in the regulation of apoptosis. To investigate this, expression of MAGE-A was evaluated. MAGE-A4 was expressed in 48% of non-small cell lung carcinomas. Ninety percent of lung carcinomas expressing MAGE-A4 were classified as squamous cell carcinomas and 10% were adenocarcinomas. Tumor-free surrounding lung tissue was negative for MAGE-A4. A molecular clone of MAGE-A4 derived from human lung cancer was stably expressed in human embryonic kidney cells (293 cells) to evaluate effects on cell death. Overexpression of MAGE-A4 increased apoptosis as measured by the apoptotic index (P < 0.0001) and caspase-3 activity (P < 0.002). Exposure to 25 micromol/L etoposide, a chemotherapeutic agent, increased the apoptotic effect (P < 0.0001). Furthermore, we show that MAGE-A4 silencing using a small interfering RNA approach results in decreased caspase-3 activity in the squamous cell lung cancer cell line H1703 by 58% (P = 0.0027) and by 24% (P = 0.028) in 293/MAGE-A4 cells. These findings suggest that MAGE-A4 expression may promote tumor cell death, sensitize malignancies to apoptotic stimuli, such as chemotherapeutic agents, and therefore may represent a tumor suppressor protein.

Aged↗
PubMed2006

Solid malignancies among patients in the Wegener's Granulomatosis Etanercept Trial.

OBJECTIVE: Etanercept is a soluble fusion protein designed to inhibit tumor necrosis factor (TNF). During the Wegener's Granulomatosis Etanercept Trial (WGET), a placebo-controlled trial of etanercept given in addition to standard therapy for remission induction and maintenance, more solid malignancies were observed in the etanercept group than in the group treated with standard therapy alone. This study was undertaken to further explore the potential association between anti-TNF therapy and the development of malignancy in these patients. METHODS: One hundred eighty patients with active WG were enrolled and followed up for a median of 27 months. At enrollment, disease characteristics, treatment history, specific medical history items, and information about previous WG treatments and risk factors for malignancy were recorded. During the trial, the occurrence of malignancies and other adverse events was recorded prospectively. RESULTS: All 6 solid malignancies observed during the WGET occurred in the etanercept group (P = 0.01 versus placebo group); based on a comparison of age- and sex-specific incidence rates, 1.92 solid malignancies would have been expected in this group. The solid malignancies included 2 cases of mucinous adenocarcinoma of the colon, 1 each of metastatic cholangiocarcinoma, renal cell carcinoma, and breast carcinoma, and 1 recurrent liposarcoma. There were no differences between the 2 treatment groups in sex distribution, disease severity, personal or family history of cancer, or tobacco and alcohol use. The etanercept group was older at baseline and less likely to be newly diagnosed with WG at the time of randomization. Patients who developed solid tumors were older than patients who did not. All etanercept-treated patients who developed solid tumors were also treated with cyclophosphamide during the trial. However, there were no differences between the groups in the amount of cyclophosphamide received during the trial or the percentage who had received cyclophosphamide before enrollment. There were also no differences in the mean duration of daily cyclophosphamide therapy or the maximum daily cyclophosphamide dosage before enrollment. CONCLUSION: Data from the WGET, the first substantial reported experience of the combined use of etanercept and cyclophosphamide in the treatment of WG, indicate that the combination of TNF inhibition and cyclophosphamide may heighten the risk of cancer beyond that observed with cyclophosphamide alone.

Aged↗
PubMed2006

Churg-Strauss syndrome.

Churg-Strauss syndrome was originally called "allergic granulomatosis and angiitis," describing the combination of eosinophilic inflammation, extravascular granulomas, and necrotizing vasculitis occurring in patients with severe asthma. It is now classified as a small-vessel vasculitis and, together with Wegener's granulomatosis and microscopic polyangiitis, as one of the vasculitides associated with antineutrophil cytoplasmic autoantibodies (ANCA). Glucocorticoid-sparing agents used in the treatment of asthma, such as leukotriene receptor antagonists, may unmask this particular form of vasculitis as oral glucocorticoids are withdrawn. ANCA occur in 40-75% of patients with active disease and typically react with myeloperoxidase. Patients' symptoms are defined by various degrees of eosinophilic inflammation and necrotizing vasculitis, which may affect any organ. On presentation, Churg-Strauss syndrome needs to be differentiated from other eosinophilic pneumonias, idiopathic hypereosinophilic syndrome, and Wegener's granulomatosis and microscopic polyangiitis. Churg-Strauss syndrome remains a rare disease with a poorly understood pathogenesis. Treatment consists primarily of glucocorticoids. Patients who have ANCA at the time of presentation should be treated according to the treatment principles for ANCA-associated vasculitides. However, the exact role of glucocorticoid-sparing immunosuppressive agents and treatment options for refractory disease remain poorly studied.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed2006

Churg-Strauss syndrome: update on clinical, laboratory and therapeutic aspects.

Originally described over fifty years ago as a disorder of asthma, eosinophilic inflammation and small vessel vasculitis, Churg-Strauss syndrome is now defined as one of the ANCA-associated vasculitides. The predilection of disease manifestations for the respiratory tract, preferred affliction of small vessels including capillaries, and the frequent occurrence of anti-neutrophil cytoplasmic antibodies (ANCA) justify this grouping together with Wegener's granulomatosis and microscopic polyangiitis. However, the allergic background in which the vasculitis presents, typically characterized by asthma and prominent peripheral blood and tissue eosinophilia, render it unique among the primary systemic vasculitis syndromes. Despite recent interest in a potential link between leukotriene receptor antagonist use for asthma and the onset of Churg-Strauss syndrome, it remains a rare disease with poorly understood pathogenesis. This review provides an update on the clinical diagnosis of Churg-Strauss syndrome in light of changing disease definitions and classifications, and focuses on evolving therapeutic approaches for this challenging systemic disorder.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed2005

BAFF is elevated in serum of patients with Wegener's granulomatosis.

BAFF (B-cell activating factor of the TNF family) plays a crucial role in B-cell survival. Elevated BAFF serum levels have been linked to several autoimmune diseases in humans, and therapies targeting BAFF were successful in animal models of rheumatoid arthritis and systemic lupus erythematosus. Wagener's granulomatosis (WG), a chronic systemic vasculitis, is characterized by circulating autoantibodies (cANCA) targeting neutrophils, which can produce BAFF. To investigate whether BAFF is involved in WG pathology, BAFF serum levels were measured by ELISA in 46 WG patients and 62 healthy donors. We report the novel finding that in WG patients serum levels of BAFF were significantly increased (median 3.95 ng/ml, p=0.009) compared to healthy controls (median 2.38 ng/ml). The difference was even more pronounced when comparing controls with untreated WG patients (median 4.61 ng/ml, p=0.001). Treatment of WG patients with glucocorticoids was associated with lower BAFF levels. The serum BAFF level in treated WG patients was about the same as in the control group. We propose that BAFF might be a pathogenic factor in WG and that targeting BAFF may represent a new therapeutic strategy in a subset of chronically relapsing WG patients with elevated BAFF levels.

Aged↗
PubMed2005

Rituximab for refractory Wegener's granulomatosis: report of a prospective, open-label pilot trial.

RATIONALE: Standard therapy for Wegener's granulomatosis is fraught with substantial toxicity and not always effective. B lymphocytes have been implicated in the pathogenesis of Wegener's granulomatosis. Their depletion has been proposed as salvage therapy for refractory disease. Earlier encouraging reports are confounded by concomitant immunosuppressive medications and include only limited available biomarker data. OBJECTIVES: To evaluate the efficacy and safety of rituximab for remission induction in refractory Wegener's granulomatosis. METHODS: A prospective open-label pilot trial was conducted with 10 patients monitored for 1 yr. Included were patients with active severe antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis, ANCA positivity, and resistance to (or intolerance of) cyclophosphamide. The remission induction regimen consisted of oral prednisone (1 mg/kg/d) and four weekly infusions of rituximab (375 mg/m(2)). Prednisone was tapered and discontinued over 5 mo. Failure to achieve remission, a clinical flare in the absence of B lymphocytes, and inability to complete the glucocorticoid taper were considered treatment failures. MAIN RESULTS: Three women and seven men (median age, 57 yr; range, 25-72 yr) were enrolled. All had ANCA reacting with proteinase-3. The median activity score at enrollment was 6 (range, 5-10). All patients tolerated rituximab well, achieved swift B-lymphocyte depletion and complete clinical remission (activity score, 0) by 3 mo, and were tapered off glucocorticoids by 6 mo. Five patients were retreated with rituximab alone for recurring/rising ANCA titers according to protocol. One patient experienced a clinical flare after B lymphocyte reconstitution. CONCLUSION: In this cohort, rituximab was a well-tolerated and effective remission induction agent for severe refractory Wegener's granulomatosis.

Adult↗
PubMed2005

A novel capture-ELISA for detection of anti-neutrophil cytoplasmic antibodies (ANCA) based on c-myc peptide recognition in carboxy-terminally tagged recombinant neutrophil serine proteases.

Testing for antineutrophil cytoplasmic antibodies (ANCA) reacting with proteinase 3 (PR3) is part of the routine diagnostic evaluation of patients with small vessel vasculitis. For PR3-ANCA detection, capture ELISAs are reported to be superior to direct ELISAs. Standard capture ELISAs, in which PR3 is anchored by anti-PR3 monoclonal antibodies (moAB), have two potential disadvantages. First, the capturing moAB may compete for epitopes recognized by some PR3-ANCA, causing occasional false-negative results. Second, the capture of recombinant PR3 mutant molecules becomes unpredictable as modifications of specific conformational epitopes may not only affect the binding of PR3-ANCA, but also the affinity of the capturing anti-PR3 moAB. Here, we describe a new capture ELISA, and its application for PR3-ANCA detection. This new assay is based on the standardized capture of a variety of different carboxy-terminally c-myc tagged recombinant ANCA target antigens using anti-c-myc coated ELISA plates. Antigen used include c-myc tagged human rPR3 variants (mature and pro-form conformations), mouse mature rPR3 and human recombinant neutrophil elastase. This new anti-c-myc-capture ELISA for PR3-ANCA detection has an intra- and inter-assay coefficient of variation of 3.6% to 7.7%, and 15.8% to 18.4%, respectively. The analytical sensitivity and specificity for PR3-ANCA positive serum samples were 93% and 100%, respectively when rPR3 with mature conformation was used as target antigen, and 83% and 100% when the pro-enzyme conformation was employed. In conclusion, this new anti-c-myc capture ELISA compares favorably to our standard capture ELISA for PR3-ANCA detection, enables the unified capture of different ANCA target antigens through binding to a c-myc tag, and allows capture of rPR3 mutants necessary for PR3-ANCA epitope mapping studies.

Animals↗
PubMed2005

Brief communication: high incidence of venous thrombotic events among patients with Wegener granulomatosis: the Wegener's Clinical Occurrence of Thrombosis (WeCLOT) Study.

BACKGROUND: Venous thrombotic events (VTEs) have been observed in Wegener granulomatosis, but the incidence rate is not known. OBJECTIVE: To measure the incidence of VTEs in patients with Wegener granulomatosis. DESIGN: Prospective, observational cohort study. SETTING: A multicenter, randomized, double-blind, placebo-controlled treatment trial for Wegener granulomatosis. PATIENTS: 180 patients with Wegener granulomatosis enrolled during periods of active disease. MEASUREMENTS: Venous thrombotic events (deep venous thromboses or pulmonary emboli) were documented and confirmed prospectively. Incidence rates were calculated on the basis of time to first VTE. RESULTS: Thirteen patients had VTEs before enrollment. During 228 person-years of prospective follow-up, 16 VTEs occurred in 167 patients with no history of VTE. Median time from enrollment to VTE for patients with an event was 2.1 months. The incidence of VTE among patients with Wegener granulomatosis was 7.0 per 100 person-years (95% CI, 4.0 to 11.4). LIMITATIONS: Although prospectively recorded, screening for VTEs did not occur. CONCLUSIONS: The incidence rate of VTEs in Wegener granulomatosis is high when compared with available rates in the general population, patients with lupus, and patients with rheumatoid arthritis. These results have important implications for clinical care of patients with Wegener granulomatosis.

Double-Blind Method↗
PubMed2005

Induction of remission by B lymphocyte depletion in eleven patients with refractory antineutrophil cytoplasmic antibody-associated vasculitis.

OBJECTIVE: To assess the clinical effects of rituximab therapy in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). METHODS: The study group comprised 11 patients who had active AAV despite receiving maximally tolerated doses of cyclophosphamide or had contraindications for cyclophosphamide use. All patients had ANCA reactive against proteinase 3. The patients received rituximab infusions and glucocorticoids to induce remission. Three patients also received plasma exchange. No other immunosuppressive agents were used. Glucocorticoids were tapered as soon as control of disease activity was achieved. Disease activity was monitored using the Birmingham Vasculitis Activity Score, modified for Wegener's granulomatosis. RESULTS: Rituximab therapy was well tolerated by all patients, and adverse events were rare. Following the rituximab infusions, circulating B lymphocytes became undetectable, and ANCA titers decreased significantly. Remission was achieved in all patients and was maintained while B lymphocytes were absent. CONCLUSION: The ability to achieve stable remissions with rituximab in patients with AAV refractory to conventional therapy suggests that B lymphocyte depletion may be a safe, effective, mechanism-based treatment modality for treatment of patients with these conditions.

Adolescent↗
PubMed2005

A serum proteomic approach to gauging the state of remission in Wegener's granulomatosis.

OBJECTIVE: To identify serum ion patterns that distinguish remission from active disease in patients with Wegener's granulomatosis (WG). METHODS: Using sera collected in the WG Etanercept Trial, we selected samples from patients who either were undergoing a period of extended disease remission or had recent flares of active WG. Unfractionated samples were randomized into sets for training and testing, such that remission sera and active disease sera could be analyzed without batch bias. Molecular species within the sera were ionized by high-resolution, matrix-assisted laser desorption ionization time-of-flight mass spectrometry. We then used a bioinformatics pattern-recognition tool to identify optimal combinations of ions. During the training stage, the clinical data (remission versus active disease) were provided in association with the spectral data from each sample. In the testing stage, we performed blinded testing on a previously unexamined set of samples. RESULTS: The most robust model, trained on a total of 82 samples (42 remission, 40 active disease), included 7 key ions with mass:charge ratios of 803.239, 2,171.672, 2,790.574, 3,085.237, 5,051.726, 5,833.989, and 6,630.465. The combined relative amplitudes of these 7 ions identified 5 distinct clusters of either remission or active disease samples during the training stage. In the testing stage, this model segregated 72 samples into the same 5 clusters, including 1 large remission cluster (n = 28) and another large active disease cluster (n = 32). Three smaller clusters of active disease or remission samples were also identified, with remission clusters populated by 2 samples in one cluster and 8 in another, and an active disease cluster populated by 2 samples. The model categorized 35 of 37 remission samples correctly (sensitivity 95%, 95% confidence interval [95% CI] 82.1-99.4) and 32 of 35 active disease samples correctly (specificity 91%, 95% CI 78.1-98.1). CONCLUSION: This serum proteomic profiling approach appears to be useful in distinguishing between states of stable clinical remission and active disease. Further validation and refinement of this strategy may help clinicians apply immunosuppressive therapies more judiciously among their patients, thereby avoiding morbidity and mortality from excessive treatment. Identification of the most robust and clinically useful combinations of ions will permit the rational selection of molecules for sequencing and analysis.

Antirheumatic Agents↗
PubMed2005

Damage caused by Wegener's granulomatosis and its treatment: prospective data from the Wegener's Granulomatosis Etanercept Trial (WGET).

OBJECTIVE: To analyze damage occurring in patients with Wegener's granulomatosis (WG) enrolled in the WG Etanercept Trial (WGET) and to correlate that damage with disease activity, adverse events, and quality of life. METHODS: The Vasculitis Damage Index (VDI) was applied to all 180 patients at trial entry and every 6 months throughout the trial. Items of damage were analyzed by presumed etiology (i.e., secondary to WG, to therapy, or both) and time of occurrence. Spearman's rank correlation coefficients were calculated between VDI scores and the Birmingham Vasculitis Activity Score for WG (BVAS/WG), frequency of flares, number of adverse events, and the patients' quality-of-life assessments. RESULTS: The mean VDI score was 1.3 at the study enrollment and 1.8 at the end of the trial. This increase was due to damage that occurred despite (or because of) therapy, including visual impairment, hearing loss, nasal blockade, pulmonary fibrosis, hypertension, renal insufficiency, peripheral neuropathy, gonadal failure, and diabetes mellitus. Only 11% of the enrolled patients had not sustained a single VDI item after 1 year of enrollment. When adjusted for baseline VDI, the baseline BVAS/WG correlated moderately well with the VDI score at 1 year (r = 0.20, P = 0.015). Increases in adjusted VDI scores also correlated with the number of adverse events, particularly among patients with limited WG (P = 0.06). CONCLUSION: Damage from both active disease and its treatment remain important problems for patients with WG. Despite the dramatic improvements in patient survival achieved over the last several decades, only a few patients with WG emerge from a period of active disease without sustaining some damage from the disease itself, its treatment, or both. An important measure of future therapeutic approaches will be their ability to reduce the damage accrued over time.

Double-Blind Method↗
PubMed2005

Herpes zoster in immunocompromised patients: incidence, timing, and risk factors.

PURPOSE: To evaluate the risk factors for herpes zoster as well as the incidence and timing of this complication in patients who were treated with immunosuppression because of active Wegener's granulomatosis. SUBJECTS AND METHODS: We studied the 180 Wegener's granulomatosis patients in the Wegener's Granulomatosis Etanercept Trial (WGET). Herpes zoster events during WGET were documented prospectively. Follow-up questionnaires were employed to describe the location, treatment, and complication(s) of herpes zoster and its therapy. Univariate and multivariate analyses were performed to evaluate risk factors, including history of herpes zoster, for the occurrence of herpes zoster during the trial. All analyses were based on the time to first occurrence of herpes zoster. RESULTS: Eighteen patients (10% of the WGET cohort) suffered a total of 19 herpes zoster episodes over a mean follow-up period of 27 months. The annual incidence of herpes zoster in the WGET cohort was 45 cases/1000 patient-years (95% confidence interval [CI]: 27, 70). The median time from enrollment to the occurrence of herpes zoster in the subgroup of patients with that complication was 16.5 months (+/- 9.4). Fifteen of the 19 herpes zoster events (79%) occurred between months 6 and 36, many months after the period of most intensive immunosuppression. In univariate analyses, history of serum creatinine > or =1.5 mg/dL before enrollment was associated with a relative risk (RR) of 3.0 (95% CI: 1.1, 7.8) for herpes zoster during WGET (P=.03). In multivariate analyses, serum creatinine > or =1.5 mg/dL was associated with an RR of 6.3 (95% CI: 2.0, 19.8; P=.002), and female sex with an RR of 4.6 (95% CI: 1.6, 13.2; P=.004). CONCLUSION: Renal dysfunction and female sex were consistently strong risk factors for herpes zoster events in this population. Contrary to expectation, most herpes zoster events did not occur during periods of most intensive immunosuppression. These data may inform studies of interventions designed to prevent herpes zoster in patients on treatment for immune-mediated diseases.

Adolescent↗
PubMed2005

Echocardiographic findings in patients with Wegener granulomatosis.

OBJECTIVE: To describe the spectrum and clinical implications of echocardiographic findings associated with Wegener granulomatosis. PATIENTS AND METHODS: We retrospectively reviewed the clinical records and echocardiographic data of consecutive patients with confirmed Wegener granulomatosis referred to the echocardiography laboratory during the 21-year period from 1976 through 1997. RESULTS: Of the 85 patients Identified as having confirmed Wegener granulomatosis, 73 (86%) were found to have echocardiographic abnormalities. In 26 (36%) of these 73 patients, lesions appeared directly related to Wegener granulomatosis. We found regional wall motion abnormalities in 17 (65%) of these 26 patients. Left ventricular systolic dysfunction with decreased ejection fraction was found in 13 patients (50%) and pericardial effusion in 5 patients (19%). Other findings Included valvulitis, left ventricular aneurysm, and a large intracardlac mass. A significantly increased mortality rate was observed among patients who had cardiac involvement of Wegener granulomatosis found by echocardiography. CONCLUSIONS: We found a high frequency of echocardiographic abnormalities that appear to be related to Wegener granulomatosis and associated with Increased mortality. Because cardiac involvement in Wegener granulomatosis often is silent and associated with Increased morbidity and worse prognosis, echocardlographic screening of patients with active Wegener granulomatosis may be of clinical value.

Adult↗
PubMed2005

Current status of outcome measures in vasculitis: focus on Wegener's granulomatosis and microscopic polyangiitis. Report from OMERACT 7.

The complexity of assessing disease activity, disease status, and damage in the vasculitides reflects the multisystemic pathologic manifestations of these often chronic illnesses. Major progress has been made in the past decade in the development of validated and widely accepted outcome measures for use in clinical trials. Over time, these tools have been regularly revised, expanded, and supplemented with new measures of disease prognosis and damage. As a result clinical research in this area has become increasingly complex. This article critically reviews the current status of tools for assessing disease activity and damage in "ANCA-associated" vasculitides (Wegener's granulomatosis and microscopic polyangiitis), summarizes the current level of validation of each measure, addresses central problems and controversies to be considered during development of new vasculitis assessment tools, and proposes a series of research agendas for consideration by the vasculitis research community.

Clinical Trials as Topic↗