Alterations in fibronectin distribution in oral mucosal vesiculo‐bullous lesions

The distribution of fibronectin in human oral mucosal vesiculo-bullous diseases was studied by indirect immunofluorescence. Subepithelial (benign mucous membrane pemphigoid and erythema multiforme) as well as intraepithelial (pemphigus vulgaris and dyskeratosis follicularis) lesions were selected. A marked accumulation of fibronectin was generally found in the lamina propria and basement membrane region, except in dyskeratosis follicularis. Intraepithelial staining occurred in erythema multiforme and dyskeratosis follicularis. In pemphigus vulgaris intercellular staining was seen in relation to acantholysis. Both mucous membrane pemphigoid and erythema multiforme showed a linear accumulation corresponding to the intact basement membrane. However, only pemphigoid lesions disclosed fibronectin on the epithelial side of the vesicles.