Abstract: In order to understand the relationship between platelet activation and the pathogenesis of psoriasis, expression of platelet.activation molecules CD62P and CD63 on platelets from 36 patients with psoriasis and from 31 healthy controls was detected by using flow cytometry and specific monoclonal antibodies against activated platelet. The results were as follows: ①Compared with normal subjects, increased expression of CD62P and CD63 on platelets from the patients with psoriasis was observed (P<0.01). ②Expression of CD62P and CD63 on platelets was positively correlated with PASI(psoriasis area and severity index) in psoriatic patients (P<0.01). ③There was no correlation between expression of platelet.activation molecules and course of disease in psoriatic patients. It is suggested that platelet activation may play an important role in microvascular changes, inflammation and higher incidence of occlusive vascular diseases found in psoriatic patients.

Key words: Psoriasis, Flow cytometry, Blood platelets, CD62P, CD63