NEUTROPHIL ANTIBODIES (PANCA) IN CHRONIC LIVER-DISEASE AND INFLAMMATORY BOWEL-DISEASE - DO THEY REACT WITH DIFFERENT ANTIGENS

Objective: A high frequency of perinuclear neutrophil antibodies (pANC A) has been described in patients with ulcerative colitis (UC) and pri mary sclerosing cholangitis (PSC). We evaluated the presence of pANCA in chronic liver disease and compared the immunoglobulin G (IgG) subcl asses of pANCA in inflammatory bowel disease with chronic liver diseas e. Since the antigen reacting with pANCA could not be determined, the antigenic role of various neutrophil antigens was evaluated. Subjects and methods: Detection of pANCA and their IgG subclass was performed b y immunofluorescence. One hundred and forty patients with chronic live r disease, 96 patients with inflammatory bowel disease and 40 healthy controls were tested for pANCA. pANCA positive and negative sera were evaluated for their reactivity with different neutrophil antigens in a n enzyme-linked immunosorbent assay (ELISA) system. Results: pANCA wer e found in 8 of 23 patients (35%) with autoimmune hepatitis, in 6 of 2 1 patients (28%) with primary biliary cirrhosis (PBC), in 18 of 25 pat ients (72%) with PSC, in 3 of 48 patients (6%) with viral hepatitis, i n 30 of 48 patients (62%) with UC, and in 2 of 48 patients (4%) with C rohn's disease. All 20 patients with alcoholic liver disease and 40 he althy controls were negative for pANCA. In contrast to the patients wi th UC who had 83% IgG1 and only 13% IgG3 antibodies, patients with PSC and PBC had an overexpression of IgG3 antibodies (PSC: 50% lgG3; PBC: 67% lgG3). A proportion of pANCA positive sera recognized lactoferrin , myeloperoxidase, cathepsin G, laminarase and alpha(1)-antitrypsin. C onclusion: pANCA is not present only in patients with UC but in autoim mune liver diseases such as PSC, autoimmune hepatitis and PBC. Conside ring the Ige subclass of pANCA, the antibody response of patients with UC is different from patients with liver disease. No unique pANCA spe cific antigen could be detected, so heterogeneity of pANCA has to be c onsidered.