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J Voswinkel

Publications and source records attributed to J Voswinkel.

14 recordsLinked to original sources
PubMed2005

B lymphocyte maturation in Wegener's granulomatosis: a comparative analysis of VH genes from endonasal lesions.

BACKGROUND: Anti-neutrophil cytoplasmic antibodies (ANCA) directed against proteinase 3 (PR3) are highly specific for Wegener's granulomatosis (WG). Evidence for a pivotal role of PR3-ANCA in the induction of vasculitis has been demonstrated. B cell clusters have been observed within endonasal biopsy specimens. OBJECTIVES: To determine whether B cell selection and maturation take place in granulomatous lesions of WG. METHODS: Granulomatous lesions and the immunoglobulin (VH) gene repertoire from nasal tissue of six WG patients-two active and two smouldering localised WG (ANCA negative, restricted to respiratory tract), plus one active and one smouldering PR3-ANCA positive generalised WG-were characterised by immunohistochemistry, polymerase chain reaction, cloning, DNA sequencing and database comparison. RESULTS: B lymphocyte-rich, follicle-like areas were observed proximal to PR3 positive cells and plasma cells in granulomatous lesions; 184 VH genes from these granulomatous lesions were compared with 84 VH genes from peripheral blood of a healthy donor. The mutational pattern of VH genes from active WG resembled memory B cells. Structural homologies of VH genes from granulomatous lesions to PR3-ANCA encoding genes were detected. Significantly more genes (55%, 45%, and 53%, respectively) from active WG compared with the healthy repertoire carried mutations to negatively charged amino acids within the binding site coding regions, favouring affinity to the positively charged PR3. CONCLUSIONS: Selection and affinity maturation of potentially PR3-ANCA producing autoreactive B cells may start in granulomatous lesions, thereby contributing to disease progression from ANCA negative localised to PR3-ANCA positive generalised WG.

Aged↗
PubMed2005

Lack of efficacy of rituximab in Wegener's granulomatosis with refractory granulomatous manifestations.

OBJECTIVE: To investigate the safety and efficacy of rituximab (RTX) in patients with refractory Wegener's granulomatosis (WG). PATIENTS AND METHODS: Eight consecutive patients with active refractory WG were included. In all patients disease activity had persisted despite standard treatment with cyclophosphamide and prednisolone, as well as tumour necrosis factor alpha blockade 3 months before inclusion in the study. Patients had particular granulomatous manifestations like retro-orbital granulomata (n=5), nodules of the lungs (n=1), and subglottic stenosis (n=2). RTX was given intravenously every 4th week in combination with the standard treatment in five patients and with methotrexate in two others. Disease extent and activity were monitored clinically by interdisciplinary care, immunodiagnostics (ANCA serology, B cells by flow cytometry), and magnetic resonance imaging. RESULTS: Beneficial response and a reduction in disease activity were seen in three patients, two of whom went into complete remission. In three other patients, disease activity remained unchanged while the disease progressed in the remaining two patients. In all patients peripheral blood B cells fell to zero during treatment with RTX. cANCA titres remained unchanged in all except one patient. CONCLUSION: In this pilot study, B lymphocyte depletion was not associated with a change of the ANCA titres or obvious clinical improvement of refractory granulomatous disease in patients with WG. Further studies are needed to evaluate the role of RTX in WG.

Adult↗
PubMed2005

Is PR3-ANCA formation initiated in Wegener's granulomatosis lesions? Granulomas as potential lymphoid tissue maintaining autoantibody production.

In Wegener's granulomatosis (WG), antiproteinase 3 (PR3) autoantibodies (PR3-ANCA) are crucial in the development of generalized vasculitis. Wegener's pathognomonic lesion, a granulomatous inflammation of the upper and lower respiratory tract, contains abundant lymphocytes and macrophages. Lymphocyte clusters in germinal center-like formation within the granulomatous lesion are frequently observed, which suggests antigen-driven B cell maturation. Wegener's autoantigen PR3, the target for autoreactive B and T cells, is expressed in granulomatous lesions. Disease progression in WG is accompanied by a profound generalized alteration of T cell differentiation with an increase of effector memory T cells (CD4(+)CD28(-)). The cytokine profile suggests an aberrant Th1-type response either to an environmental trigger and/or the autoantigen PR3 itself. Staphylococcus aureus, a risk factor for disease exacerbation, is widely present in the upper airways in WG. The Ig gene repertoire from WG lesions indicates a predominance of VH3+ B cells with affinity to PR3 as well as to the S. aureus B cell superantigen SPA. Hence, within the WG lesion, S. aureus might support the maturation of PR3-affinity B cells that enter a germinal center reaction in contact with PR3 and T cells and expand, leading to PR3-ANCA production. Thus, granulomatous lesions could represent a potential lymphoid tissue-maintaining autoantibody production rather than a simple, random leukocyte accumulation in WG.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed2003

Rituximab induces remission in refractory HCV associated cryoglobulinaemic vasculitis.

OBJECTIVES: To report the successful induction of remission with the monoclonal anti-CD20 antibody rituximab in a patient with hepatitis C virus (HCV) associated cryoglobulinaemic vasculitis and a non-Hodgkin's lymphoma (NHL) resistant to previously advocated conventional treatments. CASE REPORT: The patient was a 45 year old woman with HCV associated cryoglobulinaemic vasculitis, with purpura, arthralgia, constitutional symptoms, and a polyneuropathy. A malignant NHL was found as underlying lymphoproliferative disease. At this stage the disease was refractory to interferon alpha2b and ribavirin and to subsequent immunosuppressive treatment with cyclophosphamide. Six rituximab infusions targeting the CD20 antigen on cells of the B cell lineage induced remission of the vasculitis. Bone marrow biopsy disclosed absence of the NHL. Remission has subsequently been maintained and HCV eliminated with the new pegylated interferon alpha2b and ribavirin for nearly one year. CONCLUSIONS: Transition of the underlying "benign" lymphoproliferative disease to a malignant lymphoma may result in difficult to treat HCV associated cryoglobulinaemic vasculitis. Rituximab offers a new possibility for inducing remission in refractory HCV associated cryoglobulinaemic vasculitis and the lymphoproliferative disorder. After remission, HCV may subsequently be eliminated with pegylated interferon alpha2b and ribavirin.

Antibodies, Monoclonal↗
PubMed2002

[Induction of remission with infliximab in therapy-refractory Wegener's granulomatosis - Follow-up of six patients].

UNLABELLED: BACKGROUND AND QUESTION: The prognosis of patients with Wegener's granulomatosis (WG) refractory to standard treatment for the induction of remission (cyclophosphamide and steroids) has been poor so far. We report on the results of the follow-up of six patients refractory to the standard regimen (Fauci's scheme) with progressive, imminent visual loss, pulmonary and renal involvement, respectively. How long can remissions be successfully maintained with anti-TNF-alpha-antibody infliximab? What side effects occur? PATIENTS AND METHODS: Patients received infliximab (3 mg/kg) in addition to standard therapy with cyclophosphamide and steroids. Intervals between the first two infliximab infusions were 2 weeks, thereafter 4 weeks. Based on the impression of higher efficacy patients received 5 mg/kg infliximab for subsequent infusions. RESULTS: Remission was induced after 4-6 infliximab infusions in five patients. Remission has been maintained in four patients for 16-26 months. After 12 months a pulmonary relapse occurred in one patient, who received azathioprine for the maintenance of remission. Infliximab was stopped in another patient because of a suspected infection. In the light of high cumulative cyclophosphamide doses (100 g/275 g) and cyclophosphamide induced hemorrhagic cystitis, infliximab was added to azathioprine in the two patients with a pulmonary relapse and protrusion of the eye with imminent visual loss, respectively. Remission was induced in both patients. A carcinoid of the bronchus was diagnosed in one patient after 12 months in remission. CONCLUSION: Infliximab means a new therapeutic option and offers better perspectives for a patient group with previously bad prognosis.

Adrenal Cortex Hormones↗
PubMed2002

Effectiveness of TNF-alpha blockade with infliximab in refractory Wegener's granulomatosis.

OBJECTIVE: To study the effect of the chimeric monoclonal anti-tumour necrosis factor alpha (TNF-alpha) antibody infliximab in the induction of remission in six patients refractory to standard treatment with cyclophosphamide and corticosteroids. In four patients, other measures for treating refractory Wegener's granulomatosis (WG) that have been advocated previously, i.e. intensified cyclophosphamide therapy and additional intravenous immunoglobulin, were ineffective. METHODS: Patients received infliximab (3 mg/kg in two patients and 5 mg/kg in four patients) with a 2-week interval after the first administration and 4-week intervals between infusions until remission, in addition to cyclophosphamide and corticosteroids. Vasculitis activity was assessed with the Birmingham Vasculitis Activity Score (BVAS). A standardized interdisciplinary approach was used for the follow-up of specific organ involvement. RESULTS: Remission was induced in five patients and corticosteroid doses could be tapered. Acute-phase responses (e.g. C-reactive protein) normalized. Titres of c-ANCA (cytoplasmic pattern antineutrophil cytoplasmic antibodies) were no longer detectable. The BVAS was reduced to zero. The higher dose of infliximab (5 mg/kg) seemed more effective in inducing remission. One patient was withdrawn because of suspected systemic infection. Five patients remained in remission for 6-24 months of follow-up. CONCLUSION: The data suggest that infliximab may provide an effective and more specific therapeutic option in the treatment of active WG refractory to standard treatment.

Antibodies, Monoclonal↗
PubMed2001

B lymphocyte involvement in ankylosing spondylitis: the heavy chain variable segment gene repertoire of B lymphocytes from germinal center-like foci in the synovial membrane indicates antigen selection.

The synovial membrane (SM) of affected joints in ankylosing spondylitis (AS) is infiltrated by germinal center-like aggregates (foci) of lymphocytes similar to rheumatoid arthritis (RA). We characterized the rearranged heavy chain variable segment (VH) genes in the SM for gene usage and the mutational pattern to elucidate the B lymphocyte involvement in AS. Cryosections from an AS-derived SM were stained for B and T lymphocytes. B cells were isolated from different areas of a focus. The rearranged VH genes were amplified by semi-nested polymerase chain reaction (PCR) using oligonucleotides specific for the six different VH families and heavy chain joining segments (JHs). PCR products were cloned and sequenced.Fifty-nine of 70 different heavy chain gene rearrangements were potentially functional. Most of the rearranged genes were mutated (range, 1-15%). Thirty of 70 products had a mutational pattern typical for antigen selection. Most of the rearranged VH genes belonged to the VH3 family (54%), consistent with data from healthy donors and patients with RA, while VH4 genes, in contrast to RA, were identified less frequently (10%) and VH5 genes were over-represented (11%). In contrast to RA, neither VH6 genes nor the autoimmunity-prone VH4-34 were seen, whereas another autoimmunity-prone gene, V3-23, was predominantly used (11%). One VH1-derived and one VH3-derived B cell clone were expanded. CDR3 were shorter and more variable in length than in RA. Comparable with RA and reactive arthritis, there is a biased repertoire of selected VH genes, whereas the panel of represented genes is different and less clonal expansion was observed.

Amino Acid Sequence↗
PubMed1999

The B lymphocyte in rheumatoid arthritis: recirculation of B lymphocytes between different joints and blood.

In order to search for further evidence for a pathogenetic role of recirculating, antigen-driven B cell clones in rheumatoid arthritis (RA) rearranged VH genes were analysed for clonal relationship and somatic mutations from synovial tissue and peripheral blood of a patient with RA undergoing synovectomy of several finger joints. DNA was prepared from the synovial tissue of two finger joints and blood. PCR for the different VH families was performed with one specific oligonucleotide for each VH family and a mixture of JH-specific oligonucleotides. The PCR products were separated on a high resolution acrylamide gel differentiating one base pair difference of length. Transfer of the products onto a nylon membrane and hybridization with an oligonucleotide specific for the FR3 region revealed a polyclonal representation of rearranged VH1, VH3, VH4 and VH5 genes. The VH6 family, which is encoded by a single germline gene, was represented by few distinct bands, with some bands of identical height for both joints and blood. DNA from these bands of interest was eluted, reamplified by PCR, cloned and sequenced. Sequence analysis of 27 independent bacterial colonies allowed distribution of the different VH genes to seven B cell clones (A-G). Members of clone A were found in both joints and blood, clones B and C in one joint and blood, clone D in both joints, and clones E, F and G only in one joint. The VH regions were somatically mutated with characteristic patterns for the different clones. In conclusion, our findings confirm the systemic character of RA, because they show that not only expansion and affinity maturation of B cells occur in synovial membranes but antigen-specific B cells recirculate between different joints and blood.

Adult↗
PubMed1996

Evidence for a selected humoral immune response encoded by VH4 family genes in the synovial membrane of a patient with rheumatoid arthritis (RA).

The analysis of rearranged antibody-encoding genes from B cell foci in rheumatoid synovial tissue has characterized these cells as highly mutated memory B cells with a high proportion of members of the VH4 family. In order to characterize further the VH4 response in one patient, B cell-rich areas from different sections of synovial membrane (SM) were identified by CD20 staining, isolated by microdissection and pooled, in order to analyse highly enriched B cells without selection by in vitro culture procedures. From DNA of about 5 x 10(3) B cells rearranged VH genes were amplified by polymerase chain reaction (PCR) and cloned. Sequencing of 11 clones containing rearranged VH4 gene products revealed that seven were potentially functional, and all were mutated with 84-96% homology to known germ-line (gl) genes and VH4 gl genes amplified from the patient's genomic DNA. Analysis of the complementarity determining region (CDR) 3 revealed that two products represented members of one B cell clone which differed by five nucleotide changes. Three of the five mutations encoded amino acid replacements in CDRs indicating antigen-driven expansion of one specific clone. Additional analyses of 25 members of three B cell clones from isolated aggregates showing intraclonal diversity in one of three clones provided further evidence that antigen selection takes place in the SM. Overall, the pattern of mutations and the replacement to silent (R:S) ratios were diverse, with six products indicating antigen selection by their high R:S ratios in CDRs. Although DNA analysis does not allow a characterization of antibody specificities, we can conclude from our analysis does not allow a characterization of antibody specificities, we can conclude from our analysis of antibody-encoding genes that selection by antigen and expansion of specific clones occur in the SM against the background of polyclonal activation.

Aged↗