IgM and IgG autoantibodies from microscopic polyangiitis patients but not those with other small- and medium-sized vessel vasculitides recognize multiple endothelial cell antigens

• Published in: Clinical immunology (Orlando, Fla.) Vol. 109; no. 2; pp. 165 - 178
• Main Authors: Chanseaud, Youri, Peña-Lefebvre, Paloma García de la, Guilpain, Philippe, Mahr, Alfred, Tamby, Mathieu C, Uzan, Michèle, Guillevin, Loïc, Boissier, Marie-Christophe, Mouthon, Luc
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 01.11.2003; Elsevier
• Subjects: Autoantibodies - immunology; Autoantibody; Biological and medical sciences; Blotting, Western; Churg-Strauss Syndrome - immunology; Endothelial cell; Endothelium, Vascular - immunology; Female; Fluorescent Antibody Technique, Indirect; General aspects; Granulomatosis with Polyangiitis - immunology; Hepatitis B virus; Humans; Immunoglobulin G - blood; Immunoglobulin G - immunology; Immunoglobulin M - blood; Immunoglobulin M - immunology; Immunopathology; Male; Medical sciences; Microscopic polyangiitis; Middle Aged; Polyarteritis Nodosa - immunology; Sarcoidosis. Granulomatous diseases of unproved etiology. Connective tissue diseases. Elastic tissue diseases. Vasculitis; Autoantibody; Microscopic polyangiitis; Endothelial cell; Autoimmunity; Human; Immunopathology; Multiple; Antibody; Cardiovascular disease; Vascular disease; Vasculitis; Immunological investigation; Immunoblotting assay
• ISSN: 1521-6616; 1521-7035
• DOI: 10.1016/S1521-6616(03)00170-0

Using a quantitative immunoblotting technique on extracts of macrovascular and microvascular endothelial cells (EC), we analyzed serum IgM and IgG reactivities of patients with active disease fulfilling the ACR and Chapel Hill criteria for the diagnosis of polyarteritis nodosa (PAN) ( n = 8), PAN related to hepatitis B virus (HBV) infection (HBV-PAN) ( n = 5), Wegener's granulomatosis ( n = 6), microscopic polyangiitis (MPA) ( n = 18), Churg-Strauss syndrome ( n = 8), and patients with chronic HBV infection without PAN ( n = 5) and age- and gender-matched healthy individuals ( n = 45). MPA patients' IgM bound to 200-, 105-, 80-, 65-, 45-, 35-, and 33-kDa major bands, whereas IgM from controls and other patients bound predominantly to the 65-kDa band in EC extracts. MPA patients' IgG reacted mainly with 105-, 70-, 55-, and 38-kDa protein bands, whereas IgG from controls and other patients did not. Our results provide evidence that IgM and to a lesser degree IgG from MPA patients specifically recognize multiple EC antigens.