Epithelial antigenic specificities of circulating autoantibodies in mucosal lichen planus

Abstract

BACKGROUND: Mucosal lichen planus (LP) is an inflammatory disease of the mucous membranes of unknown origin. The antigen-specific autoantibodies or T cells responsible for this disease have not yet been established. OBJECTIVES: This study was designed to study the antigenic specificities of circulating antibodies in patients with mucosal LP and to review previous findings on this topic. METHODS: We tested a series of consecutive cases of mucosal LP in our clinic by enzyme-linked immunosorbent assay using desmoglein 3 (Dsg3) and BP180 fusion proteins. RESULTS: Three of 22 patients were positive for anti-NC16A antibodies. Interestingly, we found a middle-aged woman with severe disease with circulating anti-Dsg3 antibodies at high levels, typical of pemphigus vulgaris. Levels of these antibodies positively correlated with the severity of clinical manifestations. We failed to detect anti-desmoglein antibodies in any other patient in our series and in the literature review. CONCLUSIONS: Some patients with mucosal LP may present with circulating anti-BP180 antibodies at low levels. We also report the first case with positive anti-Dsg3 antibodies. The pathogenic relevance of these autoantibodies remains unknown.