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E Csernok

Publications and source records attributed to E Csernok.

At least 73 records · Page 4Linked to original sources
PubMed1996

Transforming growth factor-beta (TGF-beta) expression and interaction with proteinase 3 (PR3) in anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis.

TGF-beta is a multifunctional cytokine modulating the onset and course of autoimmune diseases as shown in experimental models. The aim of this study was to investigate TGF-beta expression in ANCA-associated vasculitis (AAV), and the possible interactions of this cytokine with lysosomal enzymes identified as ANCA autoantigens (e.g. PR3). This included TGF-beta effects on the translocation of the lysosomal enzymes to the cell surface of polymorphonuclear neutrophils (PMN), and the presumed activation of non-bioactive, latent TGF-beta by these enzymes. Patients with various types of systemic vasculitis (SV) were studied, including three different types of AAV (Wegener's granulomatosis (WG), Churg-Strauss syndrome (CSS) and microscopic polyangiitis (MPA)). Regardless of the type of assay applied, the TGF-beta 1 isoform was found to be over-expressed in SV, including AAV, and to correlate with disease activity as shown for WG. Mean TGF-beta 1 plasma levels in AAV patients ranged from 8.9 ng/ml (WG) to 13.3 ng/ml (CSS) (control 4.2 ng/ml; P < 0.01), while TGF-beta 2 levels were not elevated. Flow cytometry analysis showed TGF-beta 1 to be a potent translocation factor for PR3 comparable to other neutrophil-activating factors such as IL-8. PR3 membrane expression on primed PMN increased by up to 51% after incubation with TGF-beta 1. PR3 itself was revealed as a potent activator of latent TGF-beta, thus mediating bioeffects of this cytokine. These findings, together with other features of TGF-beta such as induction of angiogenesis and its strong chemotactic capacity, indicate that TGF-beta might serve as a proinflammatory factor in SV, especially in AAV.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1996

Incidence, target antigens, and clinical implications of antineutrophil cytoplasmic antibodies in rheumatoid arthritis.

OBJECTIVE: To determine the incidence of antineutrophil cytoplasmic antibodies (ANCA) in rheumatoid arthritis (RA), to detect the target antigens of ANCA, and to compare clinical and laboratory data of ANCA+ with ANCA- patients with RA. METHODS: 385 sera of patients with RA were screened for ANCA by indirect immunofluorescence. ANCA+ sera were further analyzed for target antigens by ELISA: The ANCA+ patients were compared to randomly selected ANCA- patients with RA with respect to serological and radiological variables and extraarticular involvement. RESULTS: ANCA were found in 16% of patients with RA (61/385 sera). All sera showed a perinuclear (pANCA) pattern. Antibodies directed against proteinase 3 were not observed. The analysis of ANCA+ and ANCA- patients revealed that the pANCA+ group exhibited significantly higher serological markers of inflammation (p < 0.005) and a higher incidence of rheumatoid factor (p < 0.005). Furthermore, vasculitic involvement was found at a higher frequency (p < 0.05) in the pANCA+ group. Five patients in the pANCA+ group had pulmonary involvement, but none in the pANCA- group. CONCLUSION: pANCA in RA may be a marker for a more aggressive course of disease in respect to serological variables and extraarticular manifestations including rheumatoid vasculitis and lung involvement.

Aged↗
PubMed1995

Antineutrophil cytoplasmic antibodies in systemic lupus erythematosus. Prevalence, specificities, and clinical significance.

OBJECTIVE: To examine the prevalence, subspecificities, and clinical associations of antineutrophil cytoplasmic antibodies (ANCA) in patients with systemic lupus erythematosus (SLE). METHODS: One hundred fifty-seven sera from 120 patients with SLE were examined for classic (c) and perinuclear (p) pattern ANCA by indirect immunofluorescence. Antibody subspecificities were determined by enzyme-linked immunosorbent assay (ELISA). Serologic results were correlated with clinical manifestations as categorized by the BILAG (British Isles Lupus Assessment Group) index. RESULTS: ANCA were found in 40 of the 157 sera (25%). Only a pANCA, not a cANCA, pattern of fluorescence was seen. By ELISA testing, 16 sera reacted to lactoferrin, 8 to elastase, and 4 to lysozyme. There was no reactivity to proteinase 3 (PR3) or myeloperoxidase (MPO). No correlation of pANCA, or any of the ANCA subspecificities, with organ system involvement, as categorized by the BILAG index, was found. Notably, there was no correlation of ANCA results with lupus vasculitis. CONCLUSION: The absence of cANCA, anti-PR3, and anti-MPO shows that with appropriate assay conditions, ANCA testing assists in the differentiation between SLE and the ANCA-associated vasculitides. The lack of a correlation between pANCA or any ANCA subspecificity and clinical manifestations suggests that ANCA do not identify particular clinical subsets among SLE patients, including those with lupus vasculitis.

Adult↗
PubMed1995

Distribution of the granulocyte serine proteinases proteinase 3 and elastase in human glomerulonephritis.

The serine proteinases proteinase 3 (PR3) and elastase are target antigens of antineutrophil cytoplasmic autoantibodies (ANCAs), which are found in various systemic vasculitides with rapidly progressive glomerulonephritis (RPGN). The expression of both proteinases was studied immunohistologically (avidin-biotin complex method) with murine monoclonal antibodies against PR3 (WGM2) and elastase (NP 57) in 122 human renal biopsy specimens to investigate their role in mediating renal damage. Expression of PR3 predominated in ANCA-associated RPGN and was independent of the serologic ANCA pattern (c-/p-ANCA). The PR3 staining pattern was patchy and not always related to distint granulocytes due to antigen spreading by disintegrating cells. It was found in crescentic glomeruli and the interstitum of ANCA-positive RPGN. In contrast, glomerular and interstitial elastase staining pattern was much more granulocyte related and was even found in noncrescentic glomeruli in c-ANCA- and p-ANCA-positive pauci-immune RPGN. Endothelial cell and glomerular basement membrane-bound PR3 or elastase expression were not observed. A faint glomerular PR3/elastase expression was seen in Goodpasture's syndrome and within the interstitium in crescentic mesangioproliferative glomerulonephritis (granulocyte related). Both serine proteinases were found in the glomeruli in ANCA-negative acute postinfectious glomerulonephritis. In conclusion, this study provides evidence, for the first time, for the implication of the granulocyte serine proteinases PR3 and elastase in mediating pauci-immune ANCA-positive RPGN and different forms of proliferative glomerulonephritis. The expression of ANCA antigens in ANCA-negative glomerulonephritis suggests that this finding is a marker of neutrophil activation.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1995

Treatment of anti-neutrophil cytoplasmic antibody (ANCA)-associated systemic vasculitis with high-dose intravenous immunoglobulin.

In this uncontrolled study 15 patients with ANCA-associated systemic vasculitis, who were poor responders to conventional therapy, were treated with single or multiple courses of intravenous immunoglobulin (IVIG), 30 g/day over 5 days. Clinical and serological evaluation was performed before and 4 weeks after IVIG. Six of the 15 patients experienced clinically significant benefit from IVIG. Improvement was confined to single organ manifestations (skin, ENT findings), no improvement was seen with conjunctivitis and scleritis, pericarditis or nephritis. No patient experienced complete remission after IVIG. Repeated courses of IVIG at 4-week intervals were no more effective than single courses. In six anti-proteinase 3 (PR3)-positive patients pretreatment sera were incubated with F(ab')2 fragments of the IVIG preparation in vitro to measure the inhibitory effect of IVIG on anti-PR3 activity. An inhibition of anti-PR3 activity by 25-70% was observed; this did not correlate with clinical effects. Approximately 40% of patients benefited from IVIG treatment, though complete remission of disease activity did not occur. Neither clinical characteristics nor the inhibitory effect of the IVIG preparation on serum anti-PR3 activity in vitro predicted clinical response to this treatment modality.

Adult↗
PubMed1995

Antineutrophil cytoplasmic autoantibodies, autoantigens, and systemic vasculitis.

Antineutrophil cytoplasmic antibodies (ANCA) encompass a heterogeneous group of autoantibodies targeting antigens in neutrophils (PMN), monocytes, and endothelial cells. ANCA are routinely detected by the indirect immunofluorescence technique (IFT) and at least three different patterns of fluorescence can be distinguished which have been assigned the acronyms cANCA, pANCA and aANCA. cANCA is mostly induced by proteinase 3 (PR3) antibodies (PR3-ANCA), and pANCA by myeloperoxidase (MPO) antibodies (MPO-ANCA), while aANCA has unidentified subspecificity. Over the past decade, ANCA have been the subject of extensive investigation. They have proved to be of significant value both as diagnostic tools and for follow-up in several forms of systemic vasculitis (e.g. Wegener's granulomatosis, WG; microscopic polyarteritis, MPA; Churg-Strauss syndrome, CSS) which are now termed 'ANCA-associated vasculitides'. Furthermore, it is suspected that the presence of ANCA is an important factor in the pathogenesis of these disease groups. Data regarding the detection of ANCA and their diagnostic value and role in the pathogenesis of vasculitic disorders will be discussed in this review. Growing evidence points to a pathophysiological and diagnostic relevance of the distribution of the ANCA target antigens PR3 and MPO (presence in the circulation, on cell membranes, and in tissue extracellularly). An autoimmune process has been implicated in the pathogenesis of ANCA-associated vasculitis, but it is uncertain which mechanism underlies the induction of the ANCA-related immunoresponse. In this paper mechanisms such as antigenic cross-reactivity between human PMN proteins and extrinsic antigens by molecular mimicry, idiotypic immunoglobulin regulation, and T-cell reactivity to PR3 and MPO will be discussed.

Antibodies↗
PubMed1995

Immunodiagnostic and pathophysiologic aspects of antineutrophil cytoplasmic antibodies in vasculitis.

Antineutrophil cytoplasmic antibodies (ANCA) are a heterogeneous group of autoantibodies with a wide and diverse range of clinical associations. In vasculitis, the diagnostic utility of proteinase 3 (PR3)-ANCA and myeloperoxidase-ANCA for Wegener's granulomatosis and microscopic polyangiitis, respectively, is now well established. Because of their significance as tools for diagnosis and prognosis, these autoantibodies have been analyzed extensively as markers for underlying immunopathogenic disturbances. In this review, we consider recent advances in the understanding of ANCA, focusing on their detection, diagnostic value, and role in the pathogenesis of vasculitis. In addition, promising new ways have been developed to elucidate the pathophysiologic and diagnostic relevance of the ANCA target antigens PR3 and myeloperoxidase. A great deal of attention and controversy has focused on the possible mechanisms underlying the ANCA-related immune response, such as antigenic cross-reactivity between human polymorphonuclear leukocyte proteins and extrinsic antigens by molecular mimicry, idiotype network regulation, and T cell reactivity to PR3 and myeloperoxidase.

Animals↗
PubMed1994

Anti-neutrophil cytoplasmic antibodies engage and activate human neutrophils via Fc gamma RIIa.

The presence of anti-neutrophil cytoplasmic Abs (ANCA) in many patients with systemic vasculitis suggests that ANCA may play a role in disease pathogenesis. Neutrophils from patients with Wegener's granulomatosis often express ANCA target Ags (myeloperoxidase (MPO) and proteinase 3 (PR3)) on their surface, making these intracellular primary granule enzymes accessible to these autoantibodies. Similarly, normal neutrophils can be induced to translocate MPO and PR3 to the cell surface in vitro, and we demonstrate that murine mAb ANCA IgG, but not IgM, binds to the ANCA target and engages the Fc gamma RIIa ligand-binding site on the surface of human neutrophils. In contrast to ANCA IgM, ANCA IgG also induces an oxidative burst in neutrophils (oxidation of dihydrorhodamine = 91 +/- 15 fluorescence units with anti-PR3 IgG vs 17 +/- 2 with anti-PR3 IgM, p < 0.001). Blockade of the ligand-binding site of Fc gamma RIIa with an antibinding site mAb Fab significantly reduces this ANCA IgG-triggered production of reactive oxygen species (p < 0.01). Similarly, human ANCA bind the ANCA target, engage Fc gamma RIIa, and induce an oxidative burst in neutrophils. The allelic phenotype of Fc gamma RIIa strongly influences the Fc gamma receptor engagement by ligand, and Fc gamma RIIa homozygous donors differ by more than threefold in the quantitative production of reactive oxygen intermediates (ROI) (p < 0.01). Thus, engagement of Fc gamma RIIa by the Fc region of ANCA is one mechanism by which these autoantibodies activate receptor-mediated signal transduction systems in human neutrophils to initiate programs of inflammation and tissue injury. Fc gamma receptor alleles may represent heritable disease risk factors influencing the magnitude of such a process.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1994

Activated neutrophils express proteinase 3 on their plasma membrane in vitro and in vivo.

Apart from the diagnostic value of anti-neutrophil cytoplasmic antibodies (ANCA), their detailed characterization and that of their corresponding antigens have opened new ways for the exploration of the pathogenesis of primary systemic vasculitis. ANCA are now thought to play an important functional role via activation of phagocytic cells (e.g. polymorphonuclear neutrophils (PMN)). In this study we examined the mechanisms by which ANCA could gain access to proteinase 3 (PR3) in intact PMN, at two levels: ex vivo by analysing the presence of PR3 on the plasma membrane of PMN from patients with ANCA-associated vasculitis, and in vitro by stimulation of PMN using different cytokines, including recombinant tumour necrosis factor-alpha (rhTNF-alpha) and two forms of IL-8 (produced by monocytic and endothelial cells). Using immunocytochemical staining techniques (FACS and immunoelectronmicroscopy) PR3 has been detected on the plasma membrane of PMN from patients with active ANCA-associated vasculitis. However, this phenomenon is also seen in patients with sepsis who do not have ANCA. In addition, TNF-alpha and both forms of IL-8 act synergistically and induce a translocation of PR3 from the intragranular loci to the cell surface of PMN. These results provide strong evidence for the hypothesis that ANCA are directly pathogenic by binding to PR3 which is expressed on the cell surface of primed/activated PMN.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1993

Human endothelial cells express proteinase 3, the target antigen of anticytoplasmic antibodies in Wegener's granulomatosis.

Autoantibodies directed against cytoplasmic antigens of neutrophils (ANCA), especially proteinase 3 (PR-3), have proved to be a useful clinical tool confirming the diagnosis or monitoring disease activity of Wegener's granulomatosis (WG). Although several concepts concerning the pathophysiologic potentials of ANCA have been discussed, only sparse data about ANCA-endothelium interactions have been available. In this study, we have investigated the expression of PR-3 in cytokine-treated human endothelial cells using purified anti-PR-3 antibodies of patients with WG, murine and human monoclonal anti-PR-3 antibodies as probes. We were able to show that tumor necrosis factor-alpha, interleukin-1 alpha/beta, and interferon-gamma led to an increased PR-3 expression in the cytoplasm of endothelial cells by performing polymerase chain reaction analysis, Western blot, cyto-enzyme-linked immunosorbent assays, and confocal laser scanning microscopy. Moreover, PR-3 was also translocated into the cell membrane, becoming accessible to ANCA. Our data suggest a possible direct pathogenic effect of anti-PR-3 antibodies in WG and other vasculitides. Anti-PR-3 antibodies represent an important missing link in ANCA-endothelial interactions.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1993

'Classic' anti-neutrophil cytoplasmic autoantibodies (cANCA), 'Wegener's autoantigen' and their immunopathogenic role in Wegener's granulomatosis.

Wegener's autoantigen (WA), a 29 kD multifunctional protein, is the principal target antigen of autoantibodies associated with Wegener's granulomatosis (WG). WA was first identified as proteinase 3 (PR3), which is now known to be identical with myeloblastin and AGP7. Like other lysosomal proteins, WA/PR3 displays enzymatic activity, differentiation factor activity for myeloid precursor cells, and antimicrobial functions. Neutrophilic polymorphonuclear leukocytes (PMN) and a subpopulation of monocytes contain high levels of WA/PR3 in their myeloperoxidase-positive granules. The autoantibodies from WG sera produce a finely granular, centrally accentuated fluorescence pattern on PMN and monocytes and have been designated 'classic' pattern antineutrophil cytoplasmic autoantibodies (cANCA). However, PMN/monocyte activation (in vitro/ex vivo) is associated with the translocation of WA/PR3 on the cytoplasm membrane. WA/PR3 is accessible to the WG-associated autoantibody: cANCA stimulate cytokine-preactivated PMN to produce oxygen radicals and to degranulate. Furthermore, cANCA interfere with the biological functions of WA/PR3 (e.g. inhibition of elastinolytic activity). Hence, cANCA represents not only the best seromarker for WG so far available, but several lines of evidence indicate that the autoantibodies against WA/PR3 play a major role in the pathogenesis of this enigmatic disease.

Amino Acid Sequence↗
PubMed1993

In vitro interactions of c-ANCA (antibodies to proteinase 3) with human endothelial cells.

Several concepts concerning the pathogenicity of antineutrophil cytoplasmic antibodies (ANCA) exist, but till now only sparse data about ANCA-endothelial interactions are available. In this study we have investigated the expression of proteinase 3 (PR-3) in human umbilical endothelial cells (HEC) using purified anti-PR-3 antibodies (C-ANCA) of patients with Wegener's granulomatosis (WG) and monoclonal antibodies to PR-3 (human and murine) as probes. Performing cyto-ELISAs, laser scanning microscopy and Western blot we were able to show that treatment of HEC with IL-1-alpha led to an increased PR-3 expression in the cytoplasm and to a transient translocation into the EC-membrane. Representing an important missing link of ANCA-endothelial interactions, our data give a hint at a possible direct pathogenicity of anti-PR-3 antibodies in WG and other vasculitides.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1993

ANCA in systemic vasculitides, collagen vascular diseases, rheumatic disorders and inflammatory bowel diseases.

It was the aim of this study to reevaluate the diagnostic significance and clinical implication of ANCA after testing sera from 13,606 patients for the presence of ANCA. Our data confirm the high specificity (97%) and sensitivity (80%) of cANCA for Wegener's granulomatosis. pANCA were found in renal vasculitides (60%), collagen vascular diseases (SLE 20%, Sjögren's syndrome 26%, polymyositis 16%) and rheumatic disorders (Felty's syndrome 50%, rheumatoid arthritis 20%). A third fluorescence pattern in sera of patients with inflammatory bowel disease (ulcerative colitis 28/72, Crohn's disease 6/84), here called xANCA, was seen. Target antigens of granule proteins from PMN and monocytes (proteinase 3, myeloperoxidase, elastase, cathepsin G, lactoferrin, lysozyme) were identified.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1993

Autoantibodies directed against lysozyme: a new target antigen for anti-neutrophil cytoplasmic antibodies (ANCA).

ANCA-positive sera from 1138 patients and ANCA-negative sera from 90 patients were screened for autoantibodies directed against lysozyme (LZ) by ELISA. Sera from 120 patients did react with LZ. 99 sera bound to LZ only, whereas 56 sera bound to further granule proteins, especially cathepsin G and lactoferrin. In the routine ANCA screening, most of the anti-LZ-positive sera showed a pANCA fluorescence. In total, 8% of 674 pANCA-positive sera did react with LZ. Clinically, anti-LZ antibodies were associated inflammatory rheumatologic, -renal and -bowel diseases.

Antibodies, Antineutrophil Cytoplasmic↗