DEVELOPMENT OF AN ELISA FOR RAPID DETECTION OF ANTI-TYPE-VII COLLAGENAUTOANTIBODIES IN EPIDERMOLYSIS-BULLOSA ACQUISITA

Epidermolysis bullosa acquisita (EBA) is an acquired blistering skin d isease characterized by the presence of IgG autoantibodies to type VII collagen. EBA autoantibodies recognize four major immunodominant epit opes localized within the amino-terminal, noncollagenous (NC1) domain, In this study, we developed a rapid, quantitative enzyme-linked immun osorbent assay (ELISA) to detect autoantibody activity against the com plete NC1 domain of type VII collagen with the use of an eukaryotic-ex pressed, recombinant human NC1 antigen, With the ELISA, we tested seru m from patients with EBA (n = 24), bullous systemic lupus erythematosu s (BSLE) (n = 3), bullous pemphigoid (n = 16), pemphigus (n = 11), and normal controls (n = 12). All EBA and BSLE serum, including four sera that were negative by indirect immunofluorescence, demonstrated react ivity with immobilized NC1 in the ELISA, In contrast, none of the sera from healthy control subjects or patients with unrelated blistering s kin diseases reacted with NC1. The EBA sera also reacted with recombin ant NC1 by immunoblot analysis but with less sensitivity, Thus, the ne wly developed ELISA using recombinant NC1 is a sensitive, specific ass ay and a useful tool for rapidly screening EBA and BSLE serum.