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E Csernok

Publications and source records attributed to E Csernok.

At least 37 records · Page 2Linked to original sources
PubMed2000

Neutrophils synthesize and activate TGFbeta2.

Human polymorphonuclear neutrophils (PMN) are regulated by soluble factors such as chemotactic peptides and cytokines. PMN themselves are capable of synthesizing and releasing various cytokines, thereby taking part in the afferent or inductive limb of the immune response. We report for the first time that TGFbeta2 can be synthesized and released by PMN obtained from peripheral blood. Reverse transcriptase polymerase chain reaction (RT-PCR) showed that preparations of PMN express mRNA for transforming growth factor (TGF)beta1 and TGFbeta2 but not for TGFbeta3. Only translation of TGFbeta2 into protein was observed applying different assays. Interestingly, TGFbeta2 in supernatants from stimulated PMN could be detected in the bioactive form.

Animals↗
PubMed2000

Primary vasculitides and vasculitis confined to skin: clinical features and new pathogenic aspects.

Cutaneous vasculitis is a heterogeneous group of disorders, and may occur with virtually all syndromes of vasculitis. It can occur as an isolated dermatologic disorder or as a manifestation of a potentially life-threatening systemic vasculitis. Cutaneous manifestations vary depending on the underlying cause, the size of the vessel involved and the severity and type of inflammation. In this short review, the classification, the characteristic skin manifestations of the primary vasculitides and new pathogenic aspects are discussed.

Animals↗
PubMed2000

Anti-neutrophil cytoplasmic antibodies directed against the bactericidal/permeability-increasing protein (BPI) in pediatric cystic fibrosis patients do not recognize N-terminal regions important for the anti-microbial and lipopolysaccharide-binding activity of BPI.

This study was performed to examine the prevalence and clinical correlates of bactericidal/permeability-increasing protein anti-neutrophil cytoplasmic antibodies (BPI-ANCA) in pediatric cystic fibrosis (CF) patients and to elucidate their possible role in CF pulmonary pathology. Sera of 27 CF patients were tested for ANCA by indirect immunofluorescence (IFT) and by enzyme-linked immunosorbent assay (ELISA) for ANCA sub-specificities. BPI-ANCA were examined by using standard ELISA for BPI, lipopolysaccharide-binding protein (LBP), and BPI/LBP fusion proteins to epitope map the main binding sites and look for cross-reactivity with LBP. Pulmonary function and serum concentrations of total immunoglobulin G (IgG) were measured and infections were diagnosed. In addition, release of reactive oxygen species (ROS) by neutrophil granulocytes was measured after stimulation with monoclonal BPI-ANCA. Using IFT, two patients showed atypical ANCA staining, six patients exhibited perinuclear ANCA staining, and no cytoplasmic ANCA staining was detected. Of 27 patients, 13 (48%) were BPI-ANCA (IgG) positive, and three were also immunoglobulin A (IgA) BPI-ANCA positive; one patient had ANCA against lactoferrin; and no proteinase 3 ANCA was detected in any of the patients. All BPI-ANCA bound to the C-terminal region of the molecule; none bound to the N-terminus or to LBP. There was no significant correlation between clinical data and the occurrence of BPI-ANCA in this cross-sectional study. Release of ROS from granulocytes was induced by monoclonal BPI-ANCA. Activation of neutrophils and possible modulation of BPI-mediated opsonophagocytosis and disposal of Gram-negative bacteria and lipopolysaccharides by BPI-ANCA raise the possibility that they contribute to pulmonary pathology in pediatric CF patients but intervention longitudinal studies in large groups of patients are needed to establish a causative association.

Adolescent↗
PubMed2000

Granulocyte-macrophage colony-stimulating factor (GM-CSF) but not granulocyte colony-stimulating factor (G-CSF) induces plasma membrane expression of proteinase 3 (PR3) on neutrophils in vitro.

The theoretical risk of triggering vasculitis resulting from administration of G-CSF and GM-CSF to patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV), such as Wegener's granulomatosis (WG), who develop agranulocytosis due to cytotoxic therapy, is unknown. Since there is strong evidence that activation of polymorphonuclear neutrophils (PMN) induced by binding of ANCA to PR3 or myeloperoxidase (MPO) expressed on their plasma membrane is involved in the pathogenesis of systemic vasculitides (SV), we studied the surface expression of PR3 and MPO on PMN from healthy donors in response to G-CSF and GM-CSF in vitro by flow cytometric analysis. Increasing doses of G-CSF did not alter PR3 expression on either untreated or tumour necrosis factor-alpha (TNF-alpha)-primed donor PMN significantly. In contrast, GM-CSF significantly increased PR3 membrane expression on both intact PMN and neutrophils primed with TNF-alpha. MPO expression was not significantly altered by either G-CSF or GM-CSF. In summary, these data demonstrate that GM-CSF, but not G-CSF, induces plasma membrane expression of PR3 on PMN in vitro. Since in AAV accessibility of the antigen (PR3 or MPO) to the antibody (ANCA) on the plasma membrane of PMN is thought to be essential for neutrophil activation by ANCA, the results of the present study suggest that administration of GM-CSF to patients with WG with neutropenia implies a definite theoretical risk of deterioration of vasculitis via this mechanism.

Adult↗
PubMed2000

Opsonization of apoptotic neutrophils by anti-neutrophil cytoplasmic antibodies (ANCA) leads to enhanced uptake by macrophages and increased release of tumour necrosis factor-alpha (TNF-alpha).

Since proteinase 3 (PR3)-ANCA interact with PR3 on the surface of apoptotic polymorphonuclear neutrophils (PMN) and ingestion of apoptotic PMN is known to modulate macrophage inflammatory reactions, we raised the question whether PR3-ANCA-opsonized apoptotic PMN influence the uptake by macrophages and their state of activation. We therefore analysed the effects of PR3-ANCA-opsonized apoptotic PMN on the uptake process by enzymatic assay. We further investigated the production of TNF-alpha, IL-10, IL-12 and the secretion of lipid inflammatory mediators (TxB2, leukotriene B4 (LTB4) and prostaglandin E2 (PGE2)) by human monocyte-derived macrophages using FACS and ELISA methods. We show that PMN-opsonization by PR3-ANCA substantially enhances phagocytosis by macrophages and thereby triggers the production of TNF-alpha and TxB2. These in vitro findings indicate that PR3-ANCA opsonization of apoptotic PMN might be an important mechanism in the pathogenesis of Wegener's granulomatosis (WG), prompting macrophages to produce proinflammatory mediators. These mediators, mainly TNF-alpha, might prime further PMN leading to perpetuation of the known priming-dependent mechanisms of ANCA action.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed2000

BPI-ANCA is found in reactive arthritis caused by Yersinia and Salmonella infection and recognise exclusively the C-terminal part of the BPI molecule.

OBJECTIVE: To examine the prevalence, binding sites and functional interactions of antineutrophil cytoplasmic autoantibodies (ANCA) against the bactericidal/permeability increasing protein (BPI) in reactive arthritis (ReA). METHODS: Sera were analysed for the occurrence of ANCA by indirect immunofluorescence microscopy (IIF) and ELISA. Binding sites were determined using BPI, lipopolysaccharid binding protein (LBP), and fusion proteins of both proteins in ELISA. In addition, the effect of antibodies on the antibiotic activity of BPI was examined. RESULTS: BPI-ANCA was found in patients with Yersinia- and Salmonella-triggered ReA and directed against the C-terminal portion of BPI. Goat anti BPI antibodies recognising this part inhibited the antibiotic activity of BPI in vitro. CONCLUSION: BPI-ANCA was associated with ReA triggered by Salmonella and Yersinia infection. Directed against the C-terminal part of BPI, it can potentially inhibit its antibiotic activity and might be useful to identify patients with infectious bowel disease prone to extraintestinal sequelae.

Acute-Phase Proteins↗
PubMed2000

Activation of neutrophils, eosinophils, and lymphocytes in the lower respiratory tract in Wegener's granulomatosis.

Levels of cell products released by neutrophils, eosinophils and lymphocytes were measured in the bronchoalveolar lavage fluid (BALF) of 19 patients with pulmonary active Wegener's granulomatosis (WG) to assess in vivo the magnitude of cellular activation at sites of active disease. Measurements included the BAL cell profile and BALF levels of myeloperoxidase (MPO), free proteinase 3 (fPR3), complexes of PR3 and alpha1-antitrypsin (PR3/alpha1-AT), eosinophil cationic protein (ECP), peroxidase activity (PEROX), and soluble interleukin-2 receptor (sIL-2R). Six patients also underwent a repeat examination after immunosuppressive treatment. Pulmonary active WG was found to be associated with elevated MPO, PEROX, ECP, and sIL-2R levels in BALF. Only trace amounts of fPR3 were detected, the bulk of PR3 being found in PR3/alpha1-AT complexes. Clinically effective treatment depressed BAL neutrophil counts and reversed elevated levels of MPO and PEROX but had an inconsistent effect on the BAL lymphocyte count and the sIL-2R level. In conclusion, the elevated levels of extracellular MPO and PEROX at a site of active disease and the correlation between these and clinical disease activity support the view that neutrophils are indeed an important effector cell population in WG lung disease. The present data also suggest that oxidative injury is an important aspect of neutrophil-mediated lung injury, whereas it remains unresolved whether the low levels of fPR3 in the BALF adequately reflect the situation at inflammatory tissue sites.

Adult↗
PubMed1999

Cytokine profiles in Wegener's granulomatosis: predominance of type 1 (Th1) in the granulomatous inflammation.

OBJECTIVE: To determine whether a specific cytokine pattern (type 1 [Th1] or type 2 [Th2]) predominates in Wegener's granulomatosis (WG), by evaluating interferon-gamma (IFNgamma) and interleukin-4 (IL-4) expression in different compartments of the body (i.e., biopsied nasal mucosal tissue [NBS], bronchoalveolar lavage [BAL] fluid, and peripheral blood [PB]) and comparing the findings with those in disease and healthy control subjects. METHODS: Competitive reverse transcriptase-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay were used to assess IFNgamma and IL-4 expression in T cell clones (TCC), T cell lines (TCL), and polyclonal CD4+ and CD8+ cells derived from NBS, BAL, and PB. RESULTS: Patients with WG and chronic rhinitis were found to share in situ production of messenger RNA (mRNA) specific for IFNgamma (Th1). Only 2 patients with WG expressed IL-4, whereas IL-4 mRNA PCR products were found in inflamed tissues of the disease control patients. The granuloma-derived T cells of WG patients produced only IFNgamma, while TCC, TCL, and CD4+ and CD8+ T cells from BAL and PB produced mainly IFNgamma. CONCLUSION: Our data indicate that a Thl cytokine pattern predominates in the granulomatous inflammation in patients with WG.

Adult↗
PubMed1999

Subclinical alveolar bleeding in pulmonary vasculitides: correlation with indices of disease activity.

Haemosiderin-laden alveolar macrophages are a common finding in patients with alveolar bleeding. Iron-positive macrophages, suggestive of subclinical alveolar bleeding, were found to be fairly common in bronchoalveolar lavage (BAL) fluid in primary systemic vasculitis but uncommon in collagen vascular diseases (CVDs) and rheumatoid arthritis (RA). To substantiate the impression that subclinical alveolar bleeding may be a feature distinguishing between these disorders, fibreoptic bronchoscopy and BAL were performed in 49 patients with active Wegener's granulomatosis or Churg-Strauss syndrome and 44 patients with CVDs or RA, all of them without clinically manifest alveolar bleeding. The percentage of iron-positive cells was compared with clinical and radiological findings. Only a minority of the CVD and RA patients had iron-positive alveolar macrophages; the 95th percentile of the median number of such cells was 5%. Fifty-three per cent of the patients in the vasculitis group had >5% iron-positive cells, with individual counts ranging up to 95%. Patients with iron-positive macrophages had more extensive disease, more frequent microhaematuria, a higher antineutrophil cytoplasmic antibody titre, a higher myeloperoxidase concentration in the BAL fluid and somewhat more frequent low-attenuation opacities in pulmonary high-resolution computed tomography than the patients with a low iron-positive cell count. In conclusion, subclinical alveolar bleeding was, indeed, a common finding in antineutrophil cytoplasmic antibody-associated vasculitis, which distinguished these disorders from lung disease due to collagen vascular diseases or rheumatoid arthritis. Its association with indices of disease activity, although weak in this cross-sectional study, merits a longitudinal study of its value for the long-term monitoring of vasculitis patients.

Aged↗
PubMed1999

Inflammatory cells and cellular activation in the lower respiratory tract in Churg-Strauss syndrome.

BACKGROUND: To obtain insight into the mechanisms of tissue injury in lung disease due to Churg-Strauss syndrome (CSS), the bronchoalveolar lavage (BAL) cell profile and the levels in the BAL fluid of cell products released by activated eosinophils and neutrophils were assessed. METHODS: Thirteen patients with active progressive CSS (n = 7) or CSS in partial remission (n = 6) underwent clinical staging and bronchoalveolar lavage. The levels of eosinophil cationic protein (ECP), myeloperoxidase (MPO), and peroxidase activity in the BAL fluid were determined and the results were compared with those of 19 patients with pulmonary active Wegener's granulomatosis (WG) and nine control subjects. RESULTS: In patients with progressive CSS the BAL cell profile was dominated by eosinophils, neutrophil elevation being the exception. The eosinophilia was associated with high ECP levels (4.39 ng/ml and 0. 40 ng/ml in the two CSS groups compared with unmeasurable values in the controls). Individual patients with highly active CSS also had raised MPO levels, comparable to the levels in the most active WG patients. Peroxidase activity in the BAL fluid was 1.26 U/ml and 0. 10 U/ml in the two groups of patients with CSS and 0.20 U/ml in the controls. Pulmonary disease in patients with WG was characterised by an extensive increase in MPO (0.30 ng/ml versus 0.13 ng/ml in the controls) together with high peroxidase activity in the BAL fluid (4. 37 U/ml), but only a small increase in ECP levels was seen. No correlation was found between the ECP and MPO levels in patients with CSS which suggests that eosinophil and neutrophil activation vary independently of each other. CONCLUSIONS: These findings suggest that, in addition to eosinophil activation, neutrophil activation is an important feature in some patients with highly active CSS. The balance of neutrophil and eosinophil involvement appears to be variable and this may be one explanation for the individually variable treatment requirements of patients with CSS.

Adult↗
PubMed1999

T cell receptor vbeta repertoire in bronchoalveolar lavage in Wegener's granulomatosis and sarcoidosis.

BACKGROUND: Lymphocytic alveolitis is a common feature of Wegener's granulomatosis (WG) and sarcoidosis. In pulmonary sarcoidosis analysis of the T cell receptor (TCR) configuration disclosed a biased TCR repertoire in cells obtained by bronchoalveolar lavage (BAL), suggesting that the pulmonary T cell population contains an oligoclonal, probably antigenically selected component. We examined whether this is also a feature of WG. METHODS: The distribution of 16 TCR Vbeta phenotypes on BAL cells was compared with the distribution on autologous blood cells in 8 WG patients with lymphocytic alveolitis. A control group was composed of 5 patients with active pulmonary sarcoidosis. The two groups were comparable with respect to the lymphocyte count in BAL and the distribution of the CD4+ and CD8+ T cell subsets in BAL and the blood. Overutilization of individual Vbeta phenotypes on BAL cells was considered to be significant when the percentage of positive cells in BAL doubled than in the blood and the frequency in BAL was at least 10% of total BAL T cells. RESULTS: All 5 sarcoidosis patients showed substantial overutilization of individual Vbeta families in BAL as compared with the blood. By contrast, only 2 of the 8 WG patients showed overutilization of individual Vbeta phenotypes in BAL. CONCLUSIONS: These findings do not suggest that the T cell population in BAL of WG patients contains a prominent oligoclonal component. While BAL is a convenient approach to obtain T cells from a site of active disease, BAL cells do not appear to be good material for the isolation of clonally selected T cells in WG.

Adult↗
PubMed1999

Immunopathology of ANCA-associated vasculitis.

During the past few years remarkable progress has been achieved in the understanding of the pathogenic mechanisms leading to vascular inflammation and injury in ANCA-associated vasulitides (AAV): Wegener's granulomatosis (WG), microscopic polyangiitis (MPA) and Churg Strauss syndrome (CSS). In this paper we review the immunopathology of these diseases by describing the role of autoantibodies (ANCA), dysregulation and abnormalities at the cellular level, genetic background and environmental factors that predispose to autoimmune response.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1998

Wegener's granulomatosis: anti-proteinase 3 antibodies are potent inductors of human endothelial cell signaling and leakage response.

Anti-neutrophil cytoplasmic antibodies (ANCAs) targeting proteinase 3 (PR3) have a high specifity for Wegener's granulomatosis (WG), and their role in activating leukocytes is well appreciated. In this study, we investigated the influence of PR3-ANCA and murine monoclonal antibodies on human umbilical vascular endothelial cells (HUVECs). Priming of HUVECs with tumor necrosis factor alpha induced endothelial upregulation of PR3 message and surface expression of this antigen, as measured by Cyto-ELISA, with a maximum occurrence after 2 h. Primed cells responded to low concentrations of both antibodies (25 ng-2.5 microg/ml), but not to control immunoglobulins, with pronounced, dose-dependent phosphoinositide hydrolysis, as assessed by accumulation of inositol phosphates. The signaling response peaked after 20 min, in parallel with the appearance of marked prostacyclin and platelet-activating factor synthesis. The F(ab)2 fragment of ANCA was equally potent as ANCA itself. Disrupture of the endothelial F-actin content by botulinum C2 toxin to avoid antigen-antibody internalization did not affect the response. In addition to the metabolic events, anti-PR3 challenge, in the absence of plasma components, provoked delayed, dose-dependent increase in transendothelial protein leakage. We conclude that anti-PR3 antibodies are potent inductors of the preformed phosphoinositide hydrolysis-related signal tranduction pathway in human endothelial cells. Associated metabolic events and the loss of endothelial barrier properties suggest that anti-PR3-induced activation of endothelial cells may contribute to the pathogenetic sequelae of autoimmune vasculitis characterizing WG.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1998

Churg-Strauss syndrome: serum markers of lymphocyte activation and endothelial damage.

OBJECTIVE: To find serologic markers of disease activity in patients with Churg-Strauss syndrome (CSS) linked to possible pathogenetic mechanisms by studying endothelial cell damage (soluble thrombomodulin [sTM]) in relation to T cell and eosinophil activation markers (soluble interleukin-2 receptor [sIL-2R] and eosinophil cationic protein [ECP]), and the presence of autoantibodies (antineutrophil cytoplasmic antibodies [ANCA] and anti-endothelial cell antibodies [AECA]) during both active and inactive phases of disease. METHODS: Sixteen consecutive patients who fulfilled the 1992 Chapel Hill definition of CSS were studied over a period of 4.5 +/- 3.9 years (mean +/- SD). ECP was detected by Columbo immunocapture (immunoCAP) assay, sIL-2R and sTM by enzyme-linked immunosorbent assay (ELISA), AECA by cell ELISA, and ANCA by indirect immunofluorescence and ELISA. RESULTS: In patients with active disease, ECP (8.4 +/- 90 units/ml), sIL-2R (3,725 +/- 2,310 units/ml), and sTM levels (5.5 +/- 2.9 units/liter) were significantly elevated compared with those in remission. Levels of sIL-2R showed a close correlation with levels of sTM (r = 0.75, P < 0.05). Interestingly, during remission, sIL-2R levels remained elevated in 4 of 7 patients, although the erythrocyte sedimentation rate, C-reactive protein level, and sTM level returned to the normal range (levels > 1,000 units/ml were associated with relapse). ANCA were found in only 7 patients (4 had classic ANCA, 3 had perinuclear ANCA), and AECA in 11 sera from 8 patients. In contrast to AECA, ANCA were associated with active disease. CONCLUSION: In its active state, CSS is associated with markedly increased levels of sIL-2R and ECP, indicating T cell and eosinophil activation. Elevated sTM is a sign of endothelial cell damage that can be closely linked to T cell activation, as indicated by increased sIL-2R levels.

Adolescent↗
PubMed1998

Determination of primary amino acid sequence and unique three-dimensional structure of WGH1, a monoclonal human IgM antibody with anti-PR3 specificity.

Transformed B cells making monoclonal IgM-lambda anti-PR3 antibody WGH1 from a patient with Wegener's granulomatosis were used to prepare mRNA and synthesize cDNA. PCR primers for human micro and lambda chains were then employed to amplify heavy- and light-chain V-regions followed by cloning into pCR2-1 vector and sequencing. Molecular modeling of VH regions employed knowledge-based homology modeling to obtain minimum energy conformation. The VH sequence was subgroup III with marked overall homology to VH1.9III. The VHCDR3 region of WGH1 was unique, consisting of 21 amino acid residues which included seven tyrosines as well as three negatively charged aspartic acid residues. The VL region was subgroup II with a negatively charged glutamic acid at position 100 in CDR3. Molecular modeling of VH revealed a major conformational difference in the shape of CDR3 compared with other antibodies for which three-dimensional structures have been determined. Monoclonal antibody WGH1 reacting with PR3 (a highly positively charged molecule) shows a unique reactive cassette within VHCDR3 with a number of negatively charged aspartic acid residues. WGH1 VHCDR3 contains a loop which shows a major projection not usually recorded in other previously studied antibody molecules.

Amino Acid Sequence↗