P-ANCA TARGET ANTIGENS IN ULCERATIVE-COLITIS

Introduction: Data about the nature and pathophysiological relevance o f the target antigens reacting with perinuclear antineutrophil cytopla smatic autoantibodies (p-ANCA) in ulcerative colitis are inconsistent and partly conflicting. In the majority of the previous studies only o ne singular potential target antigen was investigated. The present stu dy aimed on the simultaneous assessment of five different p-ANCA subty pes in patients with ulcerative colitis and attempted to detect reacti vity against one of the previously described antigens and to correlate specificity for different target antigens with clinical features of t he disease, Methods: Sera from 61 patients with ulcerative colitis and from 56 healthy controls were tested using indirect immunofluorescenc e and enzyme-linked immunosorbent assays specific for elastase, lactof errin, cathepsin G, myeloperoxidase and bactericidal permeability incr easing protein (BPI), p-ANCA subtypes were correlated with clinical fe atures of ulcerative colitis like disease extent or presence of extrai ntestinal manifestations. Moreover, a possible correlation to current immunosuppressive therapy was evaluated, Results: In 46% (28/61) of pa tients with ulcerative colitis and in 4% (2/56) of the controls p-ANCA were detected, p-ANCA subtypes were distributed as follows: 26% (16/6 1) anti-BPI, 16% (10/61) anticathepsin G, 15% (9/61) antielastase, 7% (4/61) anti lactoferrin, 5% (3/61) antimyeloperoxidase. Presence of an ticathepsin G antibodies was negatively correlated with immunosuppress ive therapy. No further correlations between p-ANCA subtypes and clini cal characteristics were observed. Discussion: p-ANCA subtypes in infl ammatory bowel disease react with a variety of different target antige ns and are not correlated with clinical features of the disease.