An experience for ELISA for desmoglein 1, suggesting a possible diagnostic help to determine the initial therapy for pemphigus foliaceus.

Pemphigus foliaceus (PF) is an autoimmune skin disease in which loss of adhesion between keratinocytes (i.e., acantholysis) in the granular cell layers appears to be mediated by the binding of autoantibodies against desmoglein (Dsg) 1. Although it has been suggested that the activity of the disease is rather correlated with the titer of the antibody, there are still no precise studies on the relationships between the disease activity and the titers of autoantibody against Dsg1 by using ELISA. In this study, we performed ELISA using recombinant Dsg1 (rDsg1) as antigen on 8 patients with pemphigus foliaceus in order to examine the reliability of this test for monitoring disease severity. The resultant index values of ELISA, which were defined by the formula: (OD of tested serum - OD of negative control)/(OD of positive control - OD of negative control) X 100, ranged from 16 to 264 compared with 6.41 of cutoff index value for normal sera. A patient with an index value of 213 had severe widespread erosions with erythema and required pulse therapy of methylpredonisolone (1,000 mg/day for 3 days). A patient with an index value of 111 had a moderate severity and was successfully treated with an initial dose of 30 mg/day (0.64 mg/kg) of predonisolone. The mildest patient with an index value of 16 was controlled with only topical application of 0.05% betamethasone ointment twice a day. These results suggest that ELISA index values for rDsg1 will provide a promising tool for monitoring the disease severity and for determining the initial therapy for pemphigus foliaceus.