Human epidermal cells were cultured with pemphigus antibody in the presence of hydrocortisone, methylprednisolone sodium succinate, dapsone and gold. Hydrocortisone and methylprednisolone reduced the production of the enzyme plasminogen activator but dapsone and gold had no effect. These results support the hypothesis that corticosteroids have dual effects on pemphigus through inhibition of plasminogen activator production by epidermal cells and suppression of pemphigus antibody production by B lymphocytes.