Cicatricial Pemphigoid, Bullous Pemphigoid, and Epidermolysis Bullosa Acquisita Antigens: Differences in Organ and Species Specificities and Localization in Chemically-Separated Human Skin of Three Basement Membrane Antigens

Abstract

Bullous pemphigoid, cicatricial pemphigoid, and epidermolysis bullosa acquisita are three autoimmune diseases characterized by the presence of subepidermal blisters, in vivo-bound immunoreactants along the dermoepidermal junction, and variably detectable circulating anti-basement membrane autoantibodies. In order to better characterize the antigen(s) defined by cicatricial pemphigoid sera, indirect immunofluorescence was performed on a variety of human organs, skins of different animals, and on human skin chemically-split within the lamina lucida, comparing sera from cicatricial pemphigoid patients with sera from these two other blistering diseases. Sera from patients with each disease bound to the dermoepidermal junction of every laboratory animal species examined. In contrast, more mucosal tissues were bound by anti-basement membrane autoantibodies from patients with cicatricial pemphigoid and epidermolysis bullosa acquisita than from patients with bullous pemphigoid, consistent with the marked tendency for mucosal involvement in patients with the former two diseases. In addition, one of the cicatricial pemphigoid sera stained basal cell surfaces as well as dermoepidermal junction. Differences were also apparent in the staining of chemically-split human skin. The combined findings suggest that cicatricial pemphigoid and bullous pemphigoid antigens are distinct despite their common localization within the lamina lucida of the dermoepidermal junction. These data also suggest the presence of at least two different cicatricial pemphigoid antigens.