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J Wieslander

Publications and source records attributed to J Wieslander.

At least 19 recordsLinked to original sources
PubMed1999

Goodpasture disease. Characterization of a single conformational epitope as the target of pathogenic autoantibodies.

Goodpasture disease is a prototype autoimmune disease characterized by the formation of autoantibodies against the heterotrimeric basement membrane collagen type IV, which causes a rapidly progressive glomerulonephritis. The pathogenic antibody response is directed to the non-collagenous (NC1) domain of the alpha3 chain of type IV collagen (alpha3(IV)NC1), but not to the homologous region of the alpha1(IV)NC1. To identify the conformation-dependent immunodominant epitope on the alpha3(IV)NC1, a variety of recombinant NC1 domains were constructed by replacing single residues of alpha3(IV) with the corresponding amino acids from the nonreactive alpha1(IV) chain. Replacement mutations were identified that completely destroyed the Goodpasture epitope in the alpha3(IV) chain. Based on the identification of these critical positions, the epitope was finally reconstructed within the frame of the alpha1(IV) chain. The substitution of nine discontinuous positions in the alpha1(IV)NC1 with amino acid residues from the alpha3 chain resulted in a recombinant construct that was recognized by all patients' sera (n = 20) but by none of the sera from healthy controls (n = 10). This provides, for the first time, the molecular characterization of a single immunodominant conformational epitope recognized by pathogenic autoantibodies in a human autoimmune disease, representing the basis for the development of new epitope-specific strategies in the treatment of Goodpasture disease.

Anti-Glomerular Basement Membrane Disease↗
PubMed1999

Identification of a clinically relevant immunodominant region of collagen IV in Goodpasture disease.

BACKGROUND: The characteristic feature of Goodpasture disease is the occurrence of an autoantibody response to the noncollagenous domain of the alpha3 chain of type IV collagen [alpha3(IV)NC1] in the alveolar and glomerular basement membrane. These antibodies are associated with the development of a rapidly progressive glomerulonephritis, with or without lung hemorrhage, whereas autoantibodies specific for the other alpha chains of the heterotrimeric type IV collagen probably do not cause disease. In this study, we have investigated whether differences in fine specificity of autoimmune recognition of the alpha3(IV)NC1 correlate with clinical outcome. METHODS: For mapping of antibody binding to type IV collagen, chimeric collagen constructs were generated in which parts of the alpha3(IV)NC1 domain were replaced by the corresponding sequences of homologous nonreactive alpha1(IV). The different recombinant collagen chimeras allowed the analysis of antibody specificities in 77 sera from well-documented patients. RESULTS: One construct that harbors the aminoterminal third of the alpha3(IV)NC1 was recognized by all sera, indicating that it represents the dominant target of the B-cell response in Goodpasture disease. Seventy percent of the samples recognized other parts of the molecule as well. However, only reactivity to the N-terminus of the alpha3(IV)NC1 correlated with prognosis, that is, kidney survival after six months of follow-up. CONCLUSION: The results indicate the crucial importance of antibody recognition of this particular domain for the pathogenesis of Goodpasture disease, thereby opening new avenues for the development of better diagnostic and therapeutic procedures.

Anti-Glomerular Basement Membrane Disease↗
PubMed1999

International Consensus Statement on Testing and Reporting of Antineutrophil Cytoplasmic Antibodies (ANCA)

Antineutrophil cytoplasmic antibody (ANCA) tests are used to diagnose and monitor inflammatory activity in the primary systemic small vessel vasculitides. ANCA is best demonstrated in these diseases by using a combination of indirect immunofluorescence (IIF) of normal peripheral blood neutrophils and enzyme-linked immunosorbent assays (ELISAs) that detect ANCA specific for proteinase 3 (PR3) or myeloperoxidase (MPO). For ANCA testing in "new" patients, IIF must be performed on all serum samples. Serum samples containing ANCA, any other cytoplasmic fluorescence, or an antinuclear antibody (ANA) that results in homogeneous or peripheral nuclear fluorescence then should be tested in ELISAs for PR3-ANCA and MPO-ANCA. Optimally, ELISAs for PR3-ANCA and MPO-ANCA should be performed on all serum samples. Inclusion of the most recent positive sample in the IIF or ELISA may help demonstrate a change in antibody level. Reports should use recommended terms. Any report of positive neutrophil fluorescence issued before the ELISA results are available should indicate that positive fluorescence alone is not specific for the diagnosis of Wegener granulomatosis or microscopic polyangiitis and that decisions about treatment should not be based solely on the ANCA results.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1999

The prevalence and clinical significance of alpha 1-antitrypsin deficiency (PiZ) and ANCA specificities (proteinase 3, BPI) in patients with ulcerative colitis.

Our aim was to determine the prevalence of the PiZ allele for alpha 1-antitrypsin (AAT) deficiency and some relevant antineutrophil cytoplasmic antibody (ANCA) specificities in patients with ulcerative colitis (UC), and explore a possible association between these markers. In addition, we studied the relation to disease extension and activity. Sera from 141 patients with UC (72 women) were analyzed while 50 blood donors and 54 patients with acute myocardial infarction served as controls. Serum samples were screened for PiZ with ELISA and phenotyped by isoelectric focusing. BPI-ANCA and PR3-ANCA were detected by ELISA. Results were that 8.5% (12/141) of the patients with UC were PiZ carriers, higher than expected in the general Swedish population (4.7%) (p = 0.03). There was a significant difference between PiZ-carriers and non-PiZ-carriers in the extension and severity of colitis (odds ratio = 4.1, confidence interval = 1.1, 14.9; p = 0.028, and odds ratio = 9.0, confidence interval = 1.1, 73.3; p = 0.015; respectively). BPI-ANCA and PR3-ANCA were detected in 20.5% (29/141) and 12% (17/141) (p < 0.05 compared with controls for all parameters). Occurrence of BPI-ANCA and PR3-ANCA was not related to extension or severity of colitis (p > 0.05 for both variables). We observed no association between PiZ-carrier status and occurrence of BPI-ANCA or PR3-ANCA. The increased frequency of heterozygosity for the PiZ variant of AAT deficiency among patients with UC might imply a role played by protease inhibitors for regulation of inflammation and immunologic response in UC.

Adolescent↗
PubMed1998

Capture-ELISA based on recombinant PR3 is sensitive for PR3-ANCA testing and allows detection of PR3 and PR3-ANCA/PR3 immunecomplexes.

Proteinase 3 (PR3), a constituent of azurophil granules of neutrophils (polymorphonuclear cells, PMNs), is the target antigen for most anti-neutrophil cytoplasmic antibodies (c-ANCA) in Wegener's granulomatosis (WG). We have recently developed an expression system for recombinant PR3 (rPR3) that is recognized by c-ANCA. Here, we report on the development and characterization of two monoclonal antibodies (moABs) and a rabbit polyclonal antiserum generated against this rPR3. Epitope competition analysis indicates that the moABs MCPR3-1 and MCPR3-2 recognize overlapping epitopes on the PR3 molecule that are distinct from the ones recognized by moABs 4A5 and 6A6 developed by others. Since MCPR3-2 does not appear to compete for epitopes recognized by a sizable proportion of PR3-ANCA, we used it to develop a sensitive capture enzyme linked immunosorbent assay (ELISA) for clinical PR3-ANCA testing. Both purified PMN PR3 and crude human mast cell line (HMC-1)/PR3-S176A cell lysates were used as sources of PR3 target antigen in this assay with equal analytical sensitivity and specificity. Of 109 patients with ANCA-associated disease, 91 (83.5%) and 90 (82.6%) were PR3-ANCA positive by capture ELISA when PMN-PR3 and HMC-1/PR3-S176A cell lysates were used as antigen, respectively. When HMC-1/PR3 and HMC-1/PR3-S176A cells were used as indirect immunofluorescence (IIF) substrate, 88 (80.7%) and 92 (84.4%) were PR3-ANCA positive, respectively. These differences were not statistically significant. Only 1 of 151 controls without defined ANCA-associated disease tested positive by capture ELISA with either target antigen (both negative by PR3-ANCA specific IIF). The capture ELISA can also be used to detect of PR3-ANCA immunecomplexes and, in combination with the rabbit antiserum, for the quantitative measurement of PR3 in biological fluids.

Animals↗
PubMed1998

Clinical evaluation of a capture ELISA for detection of proteinase-3 antineutrophil cytoplasmic antibody.

Detection of antineutrophil cytoplasmic antibodies (ANCA) has become a useful tool in the diagnosis of Wegener's granulomatosis and microscopic polyangiitis. However, the results obtained with indirect immunofluorescence (IIF) and by ELISA for ANCA demonstration do not always correlate. A possible explanation for this finding could be that proteins are denatured during the process of antigen purification or during coating onto the solid phase. To avoid this possibility, a monoclonal antibody to PR3 that is precoated on the plate can be used. In the present study we have used the monoclonal antibody (MoAb) 4A3 for the capture of PR3 in an ELISA, and a clinical evaluation of the diagnostic properties of the new capture ELISA has been made. The sensitivity of the capture PR3-ANCA ELISA was 85% in a material of c-ANCA positive sera. A specificity of 90% was obtained in analyses from patients having various forms of glomerulonephritis. There was a significantly higher diagnostic sensitivity of the capture PR3-ANCA ELISA (85%) compared to c-ANCA by IIF (58%) in patients with Wegener's granulomatosis with renal involvement. Capture PR3-ANCA and direct ELISA for MPO-ANCA together gave a diagnostic sensitivity of 98%, versus 75% using IIF. In conclusion, the capture PR3-ANCA ELISA seems to be a valuable tool in the diagnosis of Wegener's granulomatosis with renal involvement. Preliminary data suggest that the technique may have an advantage over direct ELISA for PR3-ANCA, as well as in the follow-up of c-/PR3-ANCA associated vasculitides. However, further prospective studies are needed to clarify this premise.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1998

Persistent high prevalence of thyroid antibodies after immunosuppressive therapy in subjects with glomerulonephritis. A prospective three-year follow-up study.

The prevalence of thyroid antibodies, indicating an autoimmune thyroiditis, has been shown to be significantly increased in patients with autoimmune diseases. A 3-year prospective follow-up study of 42 patients with biopsy-confirmed glomerulonephritis is presented. Although the majority of patients had been treated with immunosuppressants, the prevalence of thyroid peroxidase antibodies was unchanged in both females and males, 47 and 15% respectively, at follow-up. Likewise, the prevalence of thyroglobulin antibodies was unaffected as was that of antinuclear antibodies (ANA) when analysing males and females together. However, for males there was a trend to higher prevalence for ANA at follow-up. On the other hand, the prevalence of antineutrophil cytoplasmic antibodies declined. Furthermore, thyroid antibodies were not restricted to membranous nephropathy, and notably found in 4 out of the 8 patients with vasculitis.

Adult↗
PubMed1998

Relapse rate, renal survival, and cancer morbidity in patients with Wegener's granulomatosis or microscopic polyangiitis with renal involvement.

Wegener's granulomatosis (WG) and microscopic polyangiitis (MPA) are both frequently associated with antineutrophil cytoplasmic autoantibodies (ANCA). Immunosuppressive treatment has dramatically improved outcome for these patients, but today we have to deal with the problems of relapses, cases refractory to treatment, and long-term side effects of therapy. This study comprises a consecutive series of 123 patients with WG (n=56) or MPA (n=67) with biopsy-confirmed renal involvement, followed up for a median of 55 mo (range, 0.1 to 273.2 mo). ANCA was detected by enzyme-linked immunosorbent assay in 97% of patients. Nearly half of the patients (46%) relapsed. There was no statistically significant difference in overall relapse rate according to type of ANCA. Renal survival was 78% in patients alive at the end of follow-up. Three variables seemed important for renal survival: serum creatinine, the titer of proteinase 3-ANCA measured by capture enzyme-linked immunosorbent assay, and B thrombocyte count, at time of referral. Cancer incidence data were obtained from the population-based South Swedish Regional Tumor Registry. Standardized morbidity ratio was calculated using expected values from the health care region. We found an 11-fold increase in risk for bladder cancer in patients treated with cyclophosphamide for at least 12 mo. Skin carcinoma had the strongest relationship with azathioprine use for at least 12 mo and with corticosteroid therapy for at least 48 mo. In addition, four patients developed myelodysplastic syndrome and five had carcinoma in situ of the skin. Because the therapeutic regimen used today is not efficient enough to prevent relapses and is associated with a host of side effects, of which the risk for cancer is by far the most important, improved therapy and medical care are needed for patients with WG and MPA.

Adolescent↗
PubMed1997

Seminiferous tubule basement membrane. Composition and organization of type IV collagen chains, and the linkage of alpha3(IV) and alpha5(IV) chains.

Seminiferous tubule basement membrane (STBM) plays an important role in spermatogenesis. In the present study, the composition and structural organization of type IV collagen of bovine STBM was investigated. STBM was found to be composed of all six alpha-chains of type IV collagen based upon immunocytochemical and biochemical analysis. The content of alpha3(IV) chain (40%) and the alpha4(IV) chain (18%) was substantially higher than in any other basement membrane collagen. The supramolecular structure of the six alpha(IV) chains was investigated using pseudolysin (EC 3.4.24.26) digestion to excise triple-helical molecules, subsequent collagenase digestion to produce NC1 hexamers and antibody affinity chromatography to resolve populations of NC1 hexamers. The hexamers, which reflect specific arrangements of alpha(IV) chains, were characterized for their alpha(IV) chain composition using high performance liquid chromatography, two-dimensional electrophoresis, and immunoblotting with alpha(IV) chain-specific antibodies. Three major hexamer populations were found that represent the classical network of the alpha1(IV) and alpha2(IV) chains and two novel networks, one composed of the alpha1(IV)-alpha6(IV) chains and the other composed of the alpha3(IV)-alpha6(IV) chains. The results establish a structural linkage between the alpha3(IV) and alpha5(IV) chains, suggesting a molecular basis for the conundrum in which mutations in the gene encoding the alpha5(IV) chain cause defective assembly of the alpha3(IV) chain in the glomerular basement membrane of patients with Alport syndrome.

Animals↗
PubMed1997

Systemic vasculitis in a kidney transplant population.

BACKGROUND: Systemic vasculitis as original disease might adversely influence the result of kidney transplantation. METHODS: The clinical course after 32 transplantations to 26 patients with microscopic polyangiitis, Wegener's granulomatosis, Henoch-Schonlein purpura, thrombotic thrombocytopenic purpura/hemolytic uremic syndrome, or Goodpasture's disease was evaluated. The median follow-up time was 82 months (range, 4-132 months). Frozen sera from 25 transplantations were analyzed for Goodpasture antibodies, myeloperoxidase antineutrophil cytoplasmic antibodies (ANCA), and proteinase 3 ANCA. RESULTS: Survival of patients and grafts did not differ between patients and matched controls. Recurrent vasculitis occurred with seven grafts (four patients with microscopic polyangiitis or Wegener's granulomatosis, two patients with Henoch-Schonlein purpura, and one patient thrombotic thrombocytopenic purpura). New-onset hematuria was the initial renal symptom in five patients. Treatment with corticosteroids, cyclophosphamide, and/or plasma exchange was most often effective, but two grafts were lost. Proteinase 3 ANCA titers were increased to 12-738 U/ml before seven transplants. The patient with the lowest titer lost his graft due to recurrence, two other patients had reversible recurrence after 1 year and 5 years, two patients lost their grafts due to unknown/unrelated causes, and two patients' grafts remain without recurrence. Myeloperoxidase ANCA were increased to 22-39 U/ml before two transplants, which have been uneventful for 4 years. CONCLUSIONS: An awareness of the small but perpetual risk of recurrence facilitates early treatment that may save the transplant. Testing for hematuria and early transplant biopsies, and possibly monitoring of ANCA titers, are essential, but pretransplant ANCA titers have no predictive value in asymptomatic patients. Results of kidney transplantation in patients with vasculitis are as good as in other patients.

Adult↗
PubMed1997

A study of autoantibodies and circulating immune complexes in mercury-exposed chloralkali workers.

UNLABELLED: Inorganic mercury may cause immunologically mediated disease: e.g., glomerulonephritis, acrodynia, and contact allergy. Animal models have demonstrated the importance of genetic factors in determining susceptibility and resistance to autoimmunity, as well as the specific manifestation of the autoimmune response. Findings in groups of workers with occupational exposure to inorganic mercury have been inconsistent. OBJECTIVE: To investigate whether an immune response, caused by exposure to inorganic mercury (Hg), could be shown in occupationally exposed workers. METHODS: Immunoglobulin G (IgG), antinuclear autoantibodies, antibodies against thyroid, stomach or kidney antigens using indirect immunofluorescence, antibodies against glomerular basement membrane using ELISA, and circulating immune complexes in serum, and albumin in urine, were examined in Hg-exposed workers and controls. The two groups, 41 male chloralkali workers exposed to Hg vapour (mean exposure time 9 years) and 41 unexposed controls were age-matched and recruited from the same company. Hg concentrations in whole blood (B-Hg), plasma (P-Hg), and urine (U-Hg) were determined using cold vapor atomic spectrometry. DESIGN: Cross-sectional study. RESULTS: The mean B-Hg, P-Hg and U-Hg levels were 46 nmol/l, 37 nmol/l, and 27 micrograms/g creatinine in the exposed group, and 17 nmol/l, 6.9 nmol/l, and 3.4 micrograms/g creatinine in the referents. No statistically significant differences were found regarding IgG levels, urinary albumin excretion, prevalence of abnormal titers of autoantibodies or circulating immune complexes. There were no statistically significant associations between autoantibodies or immune complexes on the one hand and mercury exposure indices on the other. CONCLUSION: The results indicate that, if and when lasting autoimmune response occurs at the mercury exposure levels of the present study, it is uncommon. A small fraction of humans may, however, be susceptible to the development of autoimmunity, and there is also a possible "healthy worker" selection. Thus cross-sectional studies of moderate numbers of active workers will have low power to demonstrate autoimmune effects.

Adolescent↗
PubMed1997

Binding and inhibition of myeloperoxidase (MPO): a major function of ceruloplasmin?

Interactions between plasma proteins and MPO were studied. The protein fraction of normal plasma and serum was shown to exhibit an inhibitory effect on the peroxidase activity of MPO. Most of the inhibitory effect could be retained on an MPO-coupled affinity chromatography column. In particular, a protein with apparent mol. wt of 130 kD showed affinity for MPO. The protein was identified as ceruloplasmin by N-terminal amino acid sequencing and immunochemistry. During separation procedures the peroxidase inhibitory effect was limited to ceruloplasmin-containing fractions of plasma. Purified ceruloplasmin inhibited the peroxidase activity of MPO in a concentration-dependent manner, and exhibited selective binding to MPO-coated microtitre plates. This binding could be inhibited by MPO dissolved in buffer. Correspondingly the binding of MPO to ceruloplasmin-coated plates could be blocked by ceruloplasmin in solution, showing a physical interaction to occur between the two proteins under physiological conditions. We also found affinity to exist between MPO and C3 (and its C3d-containing fragments). However, C3 and C3 fragments did not inhibit the peroxidase reaction in vitro. We propose that ceruloplasmin takes part in the clearance and inactivation of MPO, in vivo. We also speculate that impaired inactivation of MPO may have a pathophysiological role in inflammatory diseases characterized by autoantibodies to MPO, such as rapidly progressive glomerulonephritis with P-ANCA (perinuclear anti-neutrophil cytoplasmic antibodies).

Ceruloplasmin↗
PubMed1997

Rapid screening assay for anti-GBM antibody and ANCAs; an important tool for the differential diagnosis of pulmonary renal syndromes.

BACKGROUND: Pulmonary renal syndrome is encountered in several diseases such as Goodpasture's syndrome, antineutrophil cytoplasmic antibody (ANCA) associated systemic vasculitis, systemic lupus erythematosus (SLE) and infection-associated or drug-induced glomerulonephritis. To preserve organ function it is of vital importance to make the correct diagnosis and institute adequate therapy early, in the acute phase. METHOD: An enzyme-linked immunosorbent assay (ELISA), specially designed as a rapid screening assay for antiglomerular basement membrane (anti-GBM) antibody, proteinase-3 (PR3-) ANCA and myeloperoxidase-(MPO-) ANCA were evaluated from 1060 serum samples drawn from patients with clinically suspected pulmonary renal syndrome or rapidly progressive glomerulonephritis (RPGN). RESULTS: Of the 1060 serum samples, 142 were positive for anti-GBM antibody (n = 19), PR3-ANCA (n = 60), or MPO-ANCA (n = 73). Of the 142 samples, 10 were double positive. Reanalysis of positive sera with a quantitative ELISA yielded results manifesting good correlation with those of the the rapid screening assay. Of 918 sera found to be negative in the rapid screening assay, 105 were also tested with IIF, 11 being found to be positive. However, these 11 sera manifested no specificity for PR3 or MPO, but some were specific for bactericidal/permeability-increasing proteins, lactoferrin or elastase ANCAs. Two of the patients whose sera yielded negative results in the rapid assay had systemic vasculitis. CONCLUSION: The ELISA thus detects the true antibodies to PR3, MPO, and GBM, whereas IIF detects additional specificities. The findings suggest the rapid assay results to be of high positive predictive value, and the assay to be of high diagnostic specificity and sensitivity and thus useful in the diagnostic workup in suspected cases of RPGN or pulmonary renal syndrome.

Anti-Glomerular Basement Membrane Disease↗
PubMed1997

Human autoimmune anti-proteinase 3 scFv from a phage display library.

This is the first study describing recombinant human antibody fragments directed to the autoantigen proteinase 3 (PR3) from an immune B cell source. Detection of these autoantibodies has proven valid for the diagnosis and monitoring of Wegener's granulomatosis. The described antibody fragment (scFv) was isolated from a phage display library prepared from the IgG-positive splenic lymphocytes of a patient with systemic autoimmunity. The cloning strategy was designed to maintain the diversity of the antibody variable gene repertoire, and sequencing of several variable genes demonstrated that all major heavy and light chain families were represented. We found an over-representation of particular heavy chain variable domains in splenic lymphocytes which differ from the ones frequently found in peripheral blood lymphocytes. It was possible to obtain specific scFv to PR3 after a single round of selection and the binding could be inhibited by the patients' sera. Although the antibody fragments in the splenic repertoire were found to be highly mutated, it was interesting to find that the selected scFv showed only limited somatic mutation. Furthermore, we could demonstrate that the removal of the mutations had no effect on binding specificity.

Amino Acid Sequence↗
PubMed1997

Prevalence of autoantibodies associated with glomerulonephritis, unaffected after extracorporeal shock wave lithotripsy for renal calculi, in a three-year follow-up.

Extracorporeal shock wave lithotripsy (ESWL) has become a useful tool in the treatment of renal calculi, but side effects may occur. Hitherto, two case reports have been published of an anti-glomerular basement membrane disease resulting in end-stage renal failure following ESWL treatment. In this prospective study of 59 consecutive patients undergoing ESWL for renal calculi, the prevalence of autoantibodies associated with glomerulonephritis was investigated before ESWL and at 3-year follow-up. The prevalences of antinuclear, anti-glomerular basement membrane, anti-neutrophil cytoplasmic and thyroid antibodies were found to be within the respective normal ranges prior to the first ESWL treatment and to be unaffected at follow-up.

Adult↗