An extract of cultured A431 cells contains major tissue antigens of autoimmune bullous diseases.

Abstract

Autoantibodies that are characteristic of autoimmune bullous diseases (AIBDs) can be detected by immunoblot assay using epidermal or dermal extracts. However, none of the substrates obtained by ordinary methods seems to contain a sufficient amount of all of the autoantigens involved in AIBDs, and diagnosis may require the use of several different substrates. To examine the potential of A431 cell extracts as a substrate for immunoblotting. Fourteen sera obtained from patients with major AIBDs (pemphigus vulgaris, pemphigus foliaceus, paraneoplastic pemphigus, bullous pemphigoid and epidermolysis bullosa acquisita) were tested using this substrate. Bands corresponding to desmoglein 1 and 3, desmoplakin 1 and 2, periplakin, BPAG1, BPAG2 and type VII collagen were identified distinctly with these sera. This finding suggests that culture extracts of A431 cells provide an effective substrate for the diagnosis and differential diagnosis of major AIBDs.