Autologous serum skin test for autoantibodies is associated with airway hyperresponsiveness in patients with asthma

Background: Autoimmune diseases have been implicated as a cause of intrinsic asthma; however, there is little data on the role of autoimmunity in the pathogenesis of asthma. Objective: The purpose of this study was to investigate circulating functional autoantibodies against the high-affinity IgE receptor Fc epsilon RI or IgE in patients with asthma. Methods: Twenty-eight patients with asthma and 19 control subjects were included. All subjects were skin tested with autologous serum to assess for the potential presence of receptor Fc epsilon RI or IgE autoantibodies. If the serum-induced wheal diameter was 1.5 mm larger than the histamine-induced wheal diameter and that was 3 mm larger than the saline-induced wheal diameter at 30 min, the reaction was defined positive. Results: Of the 47 total subjects (both asthma patients and control subjects), 13 (27.7%) had a positive autologous serum skin test (ASST). Of the 28 asthma patients, 8 (28.6%) were regarded as having autoimmune origin. Autoantibodies against Fc epsilon RI or IgE were found in asthma patients, irrespective of atopic status (atopy+3/13 vs. atopy -5/15). The wheal diameter related to ASST was not related to atopy. Asthma patients with ASST-positive results as compared with patients with ASST-negative results exhibited a significant increased airway hyperresponsiveness (PC20 methacholine, 2.70 +/- 1.27 vs. 9.08 +/- 2.35; p < 0.026). Conclusion: Our data demonstrate that aberrant autoantibodies against the high-affinity IgE receptor Fc epsilon RI or IgE are related to airway hyperresponsiveness in patients with asthma. Copyright (C) 2006 S. Karger AG, Basel.