title: Reactivity against complementary proteinase-3 is not increased in patients with PR3-ANCA-associated vasculitis.
abstract: The etiology of anti-neutrophil cytoplasmic antibodies (ANCA) associated vasculitides (AAV) is unknown, but the association between infections and autoimmunity has been studied extensively. In 2004, a novel theory was proposed that could link infection and autoimmunity. This 'theory of autoantigen complementarity' was based on the serendipitous finding of antibodies against complementary-PR3 (cPR3) in patients with PR3-ANCA-associated vasculitis. cPR3 demonstrated homology to several bacterial proteins, and it was hypothesized that PR3-ANCA develop in response to anti-cPR3 antibodies, as a consequence of the anti-idiotypic network. These data have not been confirmed in other patient cohorts. We investigated the presence of anti-cPR3 antibodies in a Dutch cohort of PR3-ANCA-associated vasculitis patients. Anti-cPR3 reactivity was determined in serum using ELISA. Two separate batches of cPR3 were used to determine reactivity in two separate cohorts of PR3-ANCA-associated vasculitis patients. We found that anti-cPR3-reactivity was not increased in our PR3-ANCA-associated vasculitis patients, in comparison to control groups. Further research will be necessary to prove the concept of autoantigen complementarity in autoimmune diseases.
authors: Department of Rheumatology and Clinical Immunology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands. h.tadema@reuma.umcg.nl
authors: Henko
authors: H
authors: Tadema
authors: Cees G M
authors: CG
authors: Kallenberg
authors: Coen A
authors: CA
authors: Stegeman
authors: Peter
authors: P
authors: Heeringa
mesh_terms: D056648:Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis / Q000097:blood / Q000276:immunology*; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000276:immunology*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D053146:Myeloblastin / Q000276:immunology*
chemical_list: D019268:Antibodies, Antineutrophil Cytoplasmic; D053146:Myeloblastin