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C G Kallenberg

Publications and source records attributed to C G Kallenberg.

At least 19 recordsLinked to original sources

Traditional and non-traditional risk factors contribute to the development of accelerated atherosclerosis in patients with systemic lupus erythematosus.

To determine risk factors of accelerated atherosclerosis in patients with systemic lupus erythematosus (SLE), 72 patients with inactive disease and 36 age- and sex-matched controls were included. The intima-media thickness (IMT) of the common carotid artery was determined by ultrasound. Traditional risk factors and disease-related factors were recorded. Cardiovascular risk was estimated using SCORE (systematic coronary risk evaluation). Markers of inflammation, endothelial activation and vascular remodelling (matrix metalloproteinases (MMP-3, MMP-9) and tissue inhibitor of metalloproteinase- 1 (TIMP- 1)) were determined. IMT was increased in patients (0.67 mm+/-0.13 versus 0.61 mm+/-0.11, P < 0.05). Prevalence of hypertension (33% versus 6%, P < 0.001), SCORE (2.2 (1.7-4.2) versus 1.7 (1.3-2.1), P < 0.001), as well as parameters of inflammation (CRP 1.8 (0.6-5.8) mg/L versus 0.6 (0.2-1.0) mg/L, P < 0.001) and endothelial activation (VCAM-1 505 (389-683) ng/mL versus 374 (322-427) ng/mL, P < 0.001) and von Willebrand factor (138 (59-208)% versus 48 (24-92)%, P < 0.001), were increased in patients. Vascular remodelling was altered: MMP-3 and TIMP-1 were increased (18 (10-29) ng/mL versus 8 (5-11) ng/mL, P < 0.001, and 275 (216-352) ng/mL versus 230 (197-268) ng/mL, P < 0.001, respectively), and MMP-9 was decreased in SLE (266 (147-412) ng/mL versus 348 (226-530) ng/mL, P < 0.05). Univariate analyses revealed that in patients IMT was associated with age, systolic blood pressure, SCORE and disease duration. In multivariate analysis, age and SCORE were independent predictors of IMT. In conclusion, SLE patients have an increased IMT, which is associated with traditional risk factors. Non-traditional risk factors, such as endothelial activation, altered vascular remodelling and disease duration, might play an additional role.

Atherosclerosis↗

Accelerated atherosclerosis in patients with Wegener's granulomatosis.

BACKGROUND: Several autoimmune disorders are complicated by excess cardiovascular disease. In addition to traditional risk factors, non-traditional risk factors such as endothelial activation and excessive vascular remodelling might be determinants of the progression of atherosclerosis in patients with an autoimmune disease. OBJECTIVE: To evaluate whether patients with Wegener's granulomatosis (WG) have an increased prevalence of atherosclerosis and to determine predisposing factors. METHODS: 29 WG patients (19 men; mean (SD) age, 53 (14) years) with inactive disease and 26 controls (16 men; age 53 (15) years) were studied. Common carotid intima-media thickness (IMT) was measured by ultrasound. In all individuals traditional risk factors for cardiovascular disease were determined. High sensitivity C reactive protein (hsCRP) was measured. Endothelial activation was assessed by measuring thrombomodulin, vascular cell adhesion molecule-1, and von Willebrand factor. As a marker of vascular remodelling matrix metalloproteinases (MMP-3 and MMP-9) and TIMP-1 were measured. RESULTS: IMT was increased in WG patients compared with controls (p<0.05). No differences in traditional risk factors and endothelial activation markers between patients and controls were found. Levels of hsCRP, MMPs, and TIMP-1 were increased in WG patients (p<0.05). CONCLUSIONS: Increased IMT found in WG patients cannot be explained by an increased prevalence of traditional risk factors. Although endothelial activation markers in WG patients with inactive disease were not increased, the raised levels of hsCRP, MMPs, and TIMP-1 suggest that enhanced inflammation and excessive vascular remodelling are contributing factors in the development of accelerated atherosclerosis in WG.

Adult↗

The effect of two different dosages of intravenous immunoglobulin on the incidence of recurrent infections in patients with primary hypogammaglobulinemia. A randomized, double-blind, multicenter crossover trial.

BACKGROUND: In patients with hypogammaglobulinemia, substitution with immunoglobulin is the treatment of choice to reduce both frequency and severity of bacterial infections. Even with treatment, however, infections still occur in these patients. OBJECTIVE: To determine whether doubling the standard dose of intravenous immunoglobulin would affect the incidence and duration of infections. DESIGN: Multicenter, double-blind, randomized, crossover study. SETTING: 15 outpatient clinics in the Netherlands. PATIENTS: 43 patients with primary hypogammaglobulinemia, 41 of whom completed the protocol. INTERVENTION: Patients received standard-dose immunoglobulin therapy for 9 months, followed by a 3-month washout period, and high-dose intravenous immunoglobulin therapy for 9 months, or vice versa. MEASUREMENTS: The primary outcome measures were total number and duration of infections. Other measures were periods of fever, hospital admissions, use of antibiotics, absence from school or work, and trough levels of serum immunoglobulin. Side effects from the study medication were also recorded. RESULTS: Compared with the standard dose of intravenous immunoglobulin (adults, 300 mg/kg of body weight every 4 weeks; children, 400 mg/kg every 4 weeks), high-dose therapy (adults, 600 mg/kg every 4 weeks; children, 800 mg/kg every 4 weeks) significantly reduced the number (3.5 vs. 2.5 per patient; P = 0.004) and duration (median, 33 days vs. 21 days; P = 0.015) of infections. Trough levels of IgG increased significantly during high-dose therapy. The incidence and type of side effects did not differ significantly for the two dosages. CONCLUSION: In patients with hypogammaglobulinemia, doubling the standard dose of intravenous immunoglobulin significantly reduced the number and duration of infections.

Adolescent↗

Native and recombinant proteins to analyze auto-antibodies to myeloperoxidase in pauci-immune crescentic glomerulonephritis.

The prevalence of Anti-Neutrophil Cytoplasmic Antibodies (ANCA) directed against myeloperoxidase (MPO) in pauci-immune necrotizing crescentic glomerulonephritis (NCGN) is dependent on the assay(s) used. We investigated the frequency of MPO-ANCA as detected by different assays for MPO-ANCA in a large cohort of patients with biopsy-proven pauci-immune NCGN. Sera from 121 consecutive untreated patients presenting with pauci-immune NCGN were tested for ANCA directed to proteinase-3 (PR3) at diagnosis. PR3-ANCA negative sera were tested by direct ELISA using recombinant or native MPO and by capture ELISA using two different specific monoclonal antibodies directed to MPO and three different antigenic sources. Sera from 80 relevant disease controls were tested to explore the specificity of the different assays. Thirty-eight out of 121 patients (31%) with pauci-immune NCGN did not have PR3-ANCA. Sufficient amounts of serum from 30 of these 38 PR3-ANCA negative patients were available for further testing. Recombinant and native MPO were recognized by similar numbers of sera in a direct ELISA (recombinant MPO: 93%, native MPO: 93%) and a capture ELISA (recombinant MPO: 77-87%, native MPO: 93%). Sera of patients with PR3-ANCA positive pauci-immune NCGN and disease controls were less frequently positive for MPO-ANCA in a capture ELISA (recombinant MPO: 3-7%, native MPO: 6-7%) than in a direct ELISA (recombinant MPO: 25%, native MPO: 13%). Both direct and capture ELISA assays using either native or recombinant MPO are sensitive techniques to detect MPO-ANCA in patients with pauci-immune NCGN. A capture ELISA performs better than a direct ELISA because it combines a higher specificity with a comparable sensitivity. Recombinant MPO is a good alternative for native MPO when used as antigen in a capture ELISA, but not when used in a direct ELISA because of lower specificity in this latter assay.

Antibodies, Antineutrophil Cytoplasmic↗

Renal expression of endothelial and inducible nitric oxide synthase, and formation of peroxynitrite-modified proteins and reactive oxygen species in Wegener's granulomatosis.

To investigate the role of nitric oxide (NO) in glomerular inflammation, the expression of endothelial NO synthase (eNOS) and inducible NOS (iNOS) was studied in conjunction with inflammatory cell influx, H2O2 production, and the formation of nitrotyrosines in renal biopsies from patients with Wegener's granulomatosis (WG). Renal cryostat sections from patients with WG (n=15) were stained by immunohistochemistry for eNOS, iNOS, endothelial cells (CD31), nitrotyrosines, polymorphonuclear cells (PMNs, CD15), and monocytes/macrophages (CD14, CD68). Production of H2O2 was identified by enzyme cytochemistry using diaminobenzidine. In control tissues, strong staining for eNOS was found in glomerular and interstitial tubular capillaries and cortical vessels. A significant reduction in eNOS expression was found in WG biopsies, which was associated with a reduction in CD31 expression. Expression of iNOS was found in infiltrating inflammatory cells, mainly located in the interstitium. H2O2-producing cells were detected in glomeruli and were abundantly present in the interstitium. Nitrotyrosine-positive cells, however, were almost exclusively found in the interstitium. It is concluded that renal inflammation in WG is associated with the induction of iNOS in inflammatory cells and the formation of nitrotyrosines. Expression of eNOS in glomerular capillaries is lost, most likely due to endothelial cell damage. These results suggest that decreased NO production by endothelial cells, in conjunction with increased NO production by iNOS-positive inflammatory cells, is involved in renal tissue injury in WG.

3,3'-Diaminobenzidine↗

New insights into the pathogenesis of systemic lupus erythematosus (SLE): the role of apoptosis.

In recent years disturbances in the process of apoptosis and the clearance of apoptotic cells have been put forward as fundamental in the development of autoimmunity. In this review we will discuss the data which supply evidence for this theory. We will focus on SLE as the prototype of autoimmune disease and will review both animal studies and clinical studies in SLE patients.

Animals↗

Are antineutrophil cytoplasmic antibody-associated vasculitides pauci-immune?

The role of ICs in ANCA-associated vasculitides remains controversial. The ANCA-associated vasculitides are described as being pauci-immune. We hypothesize that the absence of ICs is a result of an exaggerated inflammatory response caused by the presence of ANCAs. We present evidence indicating that ICs may play a role in the initiation or relapses of the disease. The nature of the involved antigen(s) is not yet known. Possible candidates are reviewed and include ANCA antigens, AECA antigens, and staphylococcal antigens.

Antibodies, Antineutrophil Cytoplasmic↗

Inflammation in autoimmunity: receptors for IgG revisited.

During the past decade, our knowledge of Fc receptor interactions in inflammation has increased dramatically owing to the availability of single and multiple Fc-receptor-deficient mice. The deletion of activating Fc gamma receptors protects against inflammation in models of immune-complex-mediated diseases, whereas the deletion of inhibitory Fc gamma receptors triggers increased susceptibility to immune-complex-induced inflammation. These new insights have a profound impact on our understanding of inflammation in autoimmune diseases, such as systemic lupus erythematosus (SLE). Comprehending the complex interactions between activating and inhibitory Fc gamma receptors might lead to new therapeutic approaches for human diseases, including SLE.

Animals↗

Anti-CD3-induced and anti-Fas-induced apoptosis in systemic lupus erythematosus (SLE).

Disturbances in apoptosis or in the clearance of apoptotic material might result in increased presentation of autoantigens which could be relevant to the pathogenesis of SLE. Data concerning defects in apoptosis in SLE are conflicting. To determine whether intrinsic defects in apoptosis induction occur in SLE irrespective of disease activity, we examined anti-CD3 and anti-Fas-induced apoptosis in vitro in SLE patients with inactive disease. Isolated peripheral blood lymphocytes (PBL) from 13 SLE patients and 14 healthy controls were incubated with anti-CD3, and, subsequently, after up-regulation of membrane Fas following anti-CD3 incubation, with anti-Fas. Expression of Fas and levels of apoptosis as detected by annexin V and propidium iodide staining were assessed by flow cytometry before and after the respective incubations. Fas expression on freshly isolated lymphocytes of SLE patients was increased whereas levels of circulating apoptotic cells were comparable between patients and controls. Stimulation with anti-CD3 resulted in up-regulation of membrane Fas in patients and in controls. In vitro induction of apoptosis by anti-CD3 as well as by anti-Fas occurred both in SLE patients and controls, and was higher in SLE patients after incubation with anti-CD3 as well as with anti-Fas. We conclude that Fas expression and in vitro induction of apoptosis are increased in SLE even in the absence of disease activity.

Adult↗

Effects of smoking on activation markers, Fas expression and apoptosis of peripheral blood lymphocytes.

BACKGROUND: Smoking influences numbers and function of peripheral blood lymphocytes (PBL) by a process that is badly understood. We conducted this study to evaluate whether the immune impairment of smoking might be related to changes in the expression or functionality of Fas, a cell surface molecule that plays a central role in immune homeostasis and cytotoxic activity. METHODS: PBL from 10 smoking and 10 nonsmoking healthy volunteers were isolated. Flow cytometry was performed to measure the state of activation, Fas expression and apoptosis of PBL. Functionality of Fas was tested by assessing apoptosis after incubation of isolated lymphocytes with agonistic anti-Fas antibodies in four smoking and four nonsmoking individuals. RESULTS: Smoking was associated with an increase in the percentage of Fas-expressing CD4+ T and B lymphocytes. A decrease in the percentage of activated (CD38+) B cells was observed. In vitro Fas-induced apoptosis did not appear different between smokers and nonsmokers. No differences in the percentages of circulating apoptotic lymphocytes could be demonstrated between smoking and nonsmoking individuals. Conclusion Smoking is associated with increased Fas expression on PBL in general, and on B cells in particular. This might render these cells more susceptible for apoptosis. As Fas is functionally intact this may also explain the reduced percentage of activated (CD38+) B cells found in smoking individuals. The latter may contribute to the reduced humoral immune response observed in smokers.

Adult↗

Antineutrophil cytoplasmic antibodies to proteinase 3 in Wegener's granulomatosis: epitope analysis using synthetic peptides.

BACKGROUND: Antineutrophil cytoplasmic antibodies (ANCA) to proteinase 3 (PR3) are strongly associated with Wegener's granulomatosis (WG) and are thought to be involved in its pathogenesis. Levels of PR3-ANCA do not always correspond to clinical disease activity nor to functional effects of these antibodies in vitro, suggesting differences in epitope specificity. To define relevant epitopes for PR3-ANCA, sera of WG patients were analyzed on their reactivity to linear peptides of PR3. METHODS: Fifty linear peptides of 15 amino acids in length with an overlap of 10 aa spanning the entire PR3 sequence were synthesized. Sera of 27 WG patients with active disease and 27 age- and sex-matched healthy controls, eight anti-PR3 monoclonal antibodies (mAbs), and a rabbit anti-PR3 serum were tested by enzyme-linked immunosorbent assay for reactivity to PR3 peptides. RESULTS: Rabbit anti-PR3 serum recognized three distinct peptide areas, whereas none of the anti-PR3 mAbs bound PR3 peptides. Sera of both WG patients and healthy controls recognized a restricted number of PR3 peptides. Four of these peptide areas were recognized significantly more strongly by WG sera than by control sera. Sera drawn at the initial presentation of WG mainly recognized these peptides. Two of the recognized peptide areas were located near the active center of PR3. CONCLUSION: A restricted number of epitope areas of PR3 are recognized both by WG patient sera and control sera. Four peptide areas were bound stronger by sera of WG patients at initial presentation than by healthy controls.

Adult↗

Absence of cross-reactivity to myeloperoxidase of anti-thyroid microsomal antibodies in patients with autoimmune thyroid diseases.

BACKGROUND: Thyroperoxidase is the major antigen of the thyroid microsomal antibodies (TMA) detected in autoimmune thyroid diseases. Its amino acid sequence has 44% homology with myeloperoxidase (MPO), an enzyme present in the primary granules of neutrophils and one of the major antineutrophil cytoplasmic antibodies (ANCA) antigens. The objective of the present study was to investigate the presence of cross-reactivity to MPO of TMA. METHODS: We studied sera from 51 patients with autoimmune thyroid diseases, all of them TMA-positive. The presence of ANCA was investigated by indirect immunofluorescence and by capture enzyme-linked immunosorbent assay. RESULTS: ANCA were positive in 3.9% of the TMA-positive sera and none of them reacted with MPO. In contrast, the ANCA-positive sera revealed antielastase activity. None of the ANCA-positive cases presented clinical signs of vasculitis. However, these 2 patients had been on prolonged treatment with propylthiouracil. CONCLUSIONS: We conclude that there is no cross-reactivity to MPO of TMA in patients with autoimmune thyroid diseases, possibly because of difference in the spatial configuration of the immunodominant region. The presence of ANCA in patients with autoimmune thyroid diseases without evidence of vasculitis might result from propyIthiouracil-induced polyclonal activation.

Adult↗

Novel therapies for anti-neutrophil cytoplasmic antibody-associated vasculitis.

High-dose corticosteroids in combination with cytotoxic drugs are universally accepted as the initial approach in vasculitides that are associated with anti-neutrophil cytoplasmic antibodies. Cyclophosphamide is the most effective cytotoxic drug and is used in more severe cases. Because cyclophosphamide has more severe short- and long-term side-effects than methotrexate, methotrexate is used in less severe cases. New prospects for the treatment of vasculitis include novel immunosuppressive agents (e.g. mycophenolate, 15-deoxyspergualin, and leflunomide), sequential chemotherapy (e.g. cyclophosphamide followed by azathioprine or cyclophosphamide followed by methotrexate), intravenous immunoglobulin, tumour necrosis factor-alpha directed therapy, anti-lymphocyte directed therapy (e.g. antithymocyte globulin or anti CD52/anti CD4 antibodies), anti-adhesion molecule directed therapy (e.g. anti-CD18 or intercellular adhesion molecule-1 antisense) or immunoablation using high-dose cytotoxic medication with or without stem cell rescue.

Antibodies, Antineutrophil Cytoplasmic↗

Detection of immune deposits in skin lesions of patients with Wegener's granulomatosis.

BACKGROUND: Wegener's granulomatosis (WG) is considered a pauci-immune systemic vasculitis based on the absence of immune deposits in renal biopsies of patients with active disease. In animal models of antineutrophil cytoplasmic antibody (ANCA) associated glomerulonephritis, immune deposits along the glomerular capillary wall are present at early stages of lesion development. These deposits are degraded rapidly, resulting in "pauci-immune" lesions. OBJECTIVE: To test the hypothesis that immune deposits can also be detected in early lesions of patients with WG, thereby initiating an inflammatory reaction that, in time, is augmented in the presence of ANCA, resulting in pauci-immune lesions later on. METHODS: The presence of immune deposits in skin biopsies taken within 48 hours of lesion development was investigated. Direct immunofluorescence was used to examine 32 skin biopsies for the presence of immune deposits (IgG, IgA, IgM, C3c). When possible, a comparison was made between the immunofluorescence findings in renal and skin biopsies taken at the same time. RESULTS: Four of 11 biopsies taken at initial presentation and four of 21 biopsies taken at the onset of a relapse of WG showed IgG and/or IgA containing immune deposits in the subepidermal blood vessels. All nine renal biopsies showed pauci-immune glomerulonephritis, irrespective of the presence (n=5) or absence (n=4) of immune deposits in the skin biopsy. CONCLUSION: A substantial number of skin biopsies showed immune deposits during active disease. These results could support the hypothesis that immune complexes may trigger vasculitic lesions in WG.

Adult↗

Sialometry and sialochemistry: diagnostic tools for Sjögren's syndrome.

BACKGROUND: The common occurrence of xerostomia in Sjögren's syndrome (SS) as well as the easy accessibility of saliva supports the use of sialometry and sialochemistry in the diagnosis of SS. Collection and analysis of whole saliva (oral fluid) is currently the routine technique for sialometry, despite the fact that it is rather inaccurate and impure. OBJECTIVE: To assess the value of glandular sialometry and sialochemistry as diagnostic instruments in SS. METHODS: In a group of 100 consecutive patients referred for diagnosis of SS, glandular secretory flow rates and a spectrum of salivary components (sodium, potassium, chloride, calcium, phosphate, urea, amylase, total protein) were assessed. The patients were classified as positive or negative for SS according to the revised European classification criteria. RESULTS: Patients with SS differed clearly from those who tested negative for SS, showing lower submandibular/sublingual (SM/SL) flow rates and an appreciably changed salivary composition of parotid and SM/SL saliva. Besides changes in salivary flow rate and composition, distinct sialometric profiles were observed, characteristic of either early or late salivary manifestation of SS, or of the xerogenic side effects of medication. CONCLUSIONS: Glandular sialometry and sialochemistry are not only useful tools for differentiating SS from other salivary gland disease in clinical practice, but they also have great potential as diagnostic criteria for SS, showing distinct sialometric and sialochemical changes as well as profiles. Being simple, safe (non-invasive), and sensitive (early disease detection), they have three major advantages over other oral tests for SS.

Adult↗

Expression of costimulatory molecules on peripheral blood lymphocytes of patients with systemic lupus erythematosus.

OBJECTIVE: In systemic lupus erythematosus (SLE) autoantibody production is T cell dependent. For a proper T and B cell interaction, signalling of costimulatory molecules on these cells is necessary. The expression of costimulatory molecules on peripheral blood lymphocytes in patients with SLE in conjunction with disease activity was measured to evaluate whether expression of costimulatory molecules in SLE is increased. METHODS: Thirteen patients with SLE with active disease, 10 patients with inactive disease, and 14 controls entered the study. In addition, samples from 10 of the 13 patients with active disease could be studied at a moment of inactive disease as well. Isolated peripheral blood lymphocytes were stained for the lymphocyte subset markers CD4, CD8, CD19, their respective activation markers CD25, HLA-DR, CD38, and the costimulatory molecules CD40L, CD28, CD40, CD80, and CD86. Expression was measured by flow cytometry. RESULTS: Peripheral blood lymphocytes of patients with SLE showed signs of increased activation at the moment of active disease. Almost all CD4+ T cells expressed CD28, both in patients and in controls. CD80 expression on CD19+ B cells was low in both groups and did not correlate with disease activity. In contrast, the percentage of CD19+ B cells expressing CD86 was increased in patients with SLE even in patients with inactive disease (p=0.04) and correlated with the SLEDAI score (p=0.0005) and levels of anti-dsDNA (p=0.006). No changes in CD40 or CD40L expression were found in the patients with SLE. CONCLUSION: In patients with SLE the expression of CD86 on CD19+ B cells is increased and is associated with disease activity, B cell activation, and levels of anti-dsDNA. The increased CD86 expression will render (autoreactive) B cells more susceptible for T cells. This can facilitate autoantibody production and might be a target for immunosuppressive treatments.

Antigens, CD↗