[Use of the immunoblotting technic for the study of antibodies present in the serum of patients with bullous pemphigoid].

Bullous pemphigoid (BP) is an autoimmune disease characterized, at histology, by subepidermal bullous separations. Antibodies (Ab) and complement are present at the dermal-epidermal junction, and most patient with the disease have serum antibodies directed against a normal constituent of stratified epithelia (10, 25). During the past few years, the immunotransfer technique has been used to study autoimmune bullous diseases of the skin. The antigen (Ag) of bullous pemphigoid has been described by Stanley et al. (16, 17) as the polypeptidic doublet 220-240 KD. However, different results in favour of an heterogeneous antigen have been obtained by Labib et al. (11) who reported the presence of 5 separate polypeptides: 240, 200, 180, 97 and 77 KD. The purpose of the present study was to confirm on infirm these findings. We recorded the antigens recognized at immunotransfer by the circulating antibodies of BP patients, then extended this study to sera from BP patients in whom no antibody had been detected by indirect immunofluorescence (IIF). We report the results of our immunotransfer study in 9 seropositive and 9 seronegative BP patients and in 11 seronegative controls. The antigenic extract we used was prepared from suspensions of epidermal cells and represented the intracellular BP antigen. Epidermal cell suspensions were obtained by trypsinization of human abdominal skin. The cells were homogenized in a Tris-HCl 10 mM pH 7.8 buffer with SDS 2 p. 100 and B-mercaptoethanol 5 p. 100. The soluble proteins were analyzed in a polyacrylamide gel in the presence of SDS.(ABSTRACT TRUNCATED AT 250 WORDS)