[Detection of serum desmoglein antibody level using enzyme-linked immunosorbent assay (ELISA) for monitoring disease activity in patients with pemphigus vulgaris].

OBJECTIVE: Pemphigus is an autoimmune blistering disease of skin and mucous membranes. Pemphigus vulgaris (PV) is a major subtype of pemphigus, which is histologically characterized by suprabasal acantholysis. The major antigen in PV is desmosomal glycoproteins desmoglein (Dsg) 3. The autoantibodies against Dsg3 cause loss of adhesion between keratinocytes. Some PV patients also have circulating anti-Dsg1 autoantibodies. Enzyme-linked immunosorbent assays (ELISAs) with recombinant Dsg3 and Dsg1 are highly sensitive and specific for detecting anti-Dsg3 and anti-Dsg1 autoantibodies in PV patients. To evaluate the role of desmosomal glycoproteins desmoglein (Dsg3) ELISA and Dsg1 ELISA for detecting anti-Dsg3 and anti-Dsg1 autoantibodies in monitoring disease activity in Pemphigus vulgaris patients. METHODS: Twenty PV patients with long-term follow-up were included. We tested their serial sera with modified Dsg3 ELISA (MESACUP Desmoglein TEST "Dsg3", Medical & Biological Laboratories Co. LTD.), Dsg1 ELISA(MESACUP Desmoglein TEST "Dsg1", Medical & Biological Laboratories Co. LTD.) and indirect immunofluorescence (IIF). Then we analyzed the correlation between Dsg3 ELISA index values, Dsg1 ELISA index values, IIF titres and disease activity scores (ABSIS) along the time course. RESULTS: There were significant correlations between Dsg3 ELISA index values, Dsg1 ELISA index values, IIF titres and disease activity scores (both skin scores and oral scores) (P<0.01) along the time course. Significant differences of Dsg3 ELISA index values, Dsg1 ELISA index values and IIF titres between active time-point group and clinical remission time-point group were also observed (P<0.01). We found that Dsg3 ELISA index values, Dsg1 ELISA index values and IIF titres fluctuated in parallel with disease activity, and ELISA index values were superior to IIF titres. CONCLUSION: Dsg3 ELISA index values fluctuating in parallel with disease activity are useful to monitor disease activity, predict flares or relapses and plan the schedules for tapering the drugs.