Profile of anti-stratum corneum autoantibodies in psoriatic patients

Using autologous normal skin and freshly separated sera, the titers of circulating anti-stratum corneum (SC) IgG autoantibodies, which were predominantly demonstrated by ordinary indirect immuno-fluorescence (IF), and those of complement-fixing anti-SC autoantibodies were compared in 16 psoriatic patients with active lesions, 16 patients with nonpsoriatic inflammatory dermatoses, and 11 normal subjects. As in patients with other inflammatory dermatoses, the titers of IgG anti-SC autoantibodies in psoriatic patients were not specifically higher than in normal controls but were more variable, indicating that their circulating levels are dependent on a delicate balance between consumption at inflammatory sites and a secondary increase due to SC-antigen release following inflammation. The titers of complement-fixing anti-SC autoantibodies were much higher than those of IgG autoantibodies in most cases but they were not particularly high in psoriatic patients. From these findings, we think that if these autoantibodies are really involved in complement activation in inducing the transepidermal leukocyte migration of psoriatic lesions, a local factor of psoriatic epidermis, which may facilitate the permeation of these antibodies toward the SC, plays a more important role than the actual circulating antibody levels.