Sixteen patients with varying degrees of alopecia areata, without an associated disease were examined before and during a local DNCB therapy for evidence of immunological abnormalities in both cellular and humoral immune parameters. The mean values of IgG, IgA, IgM, IgE, complement factors C3 and C4 and of alpha 1-antitrypsin were found within the norm, of the C1-Inhibitor slight diminished. Antinuclear antibodies in low titer were observed in three, antithyroglobulin antibodies in two young patients. Immuncomplexes were always negative. The mean value for T cells (67 +/- 7%) was normal as well as the lymphocyte transformation to phytohemagglutin, pokweed-mitogen and candidin, the PPD stimulation was slight reduced. No changes in the immunprofile were observed during the DNCB therapy, with exception of a slight, but significant increase of the T cell number from 63 +/- 8% to 77 +/- 5%. Our findings exclude a common systemic immune defect in alopecia areata.