[The role of urokinase-type plasminogen activator in the pathogenesis of pemphigus].

OBJECTIVE

To investigate the changes of urokinase-type plasmino-gen activator (u-PA) in the process of acantholysis in pemphigus and observe the influence of purified urokinase on the cultured skin explant.

METHODS

The expression of urokinase antigen on the pemphigus organ model was revealed by immunohistochemical method; PA activity was assayed in the acantholysis model; the influence of urokinase on the epidermis was observed by adding purified urokinase into the cultured skin explant.

RESULTS

PA activity was elevated in the acantholysis model at 24 hour and was continuing its increase at 48 and 72 hours. The expression of urokinase was high in the epidermis of pemphigus organ model; purified urokinase could induce acantholysis like changes.

CONCLUSION

Pemphigus antibody induces acantholysis through activating keratinocytes. The latter secretes an elevated u-PA, which locates on the membrane of the epidermal cells producing a limited pro-teolysis which damages the cohesion of epidermal cells.