Abstract: We purified IgG in the serum of apatient with pemphigus vulgaris.After immunizing BALB/c mice with purified pemphigus autoantibody(Pab),spleen cells of the mice were fused with a myeloma cell line SP2/0,and we selected two hybridoma cell lines(PI₁,PI₁) which produced anti-idio-type antibody specific to the pemphigus antibody IgG.The anti-idiotype antibody produced by PI₁ hybridoma celline was characterized,it was of the IgG2 bsubclass.PI₁ could inhibit the binding of Pab to pemphigus antigen.The binding of PI₁ to Pab could beinhibited by the IgG antibody in the sera of other patients with pemphigus.Both competitive inhibition and neutralization inhibition were dose-depen-dent.This suggests that idiotype antibody recognised by PI₁ is closely asociated with the paratopy of Pab.The potential usefulness of PI₁ in the study of the clinical diagnosis,treatment and immune regulation of patients with pemphigus is discussed.

Key words: Pemphigus, Antibodies,monoclonal