Abstract: Objective To investigate the correlation between expression of four adhesion molecules in sera and in skin lesions of patients with psoriasis vulgaris, as well as their relevance to clinical severity of the disease. Methods Enzyme-linked immunosorbent assay (ELISA) was used to determine the serum levels of ICAM-1, ICAM-3, VCAM-1 and ELAM-1 in 36 patients with plaque type psoriasis vulgaris and 36 healthy controls. Avidin biotin immunoperoxidase staining system was employed to quantitate expression of the four adhesion molecules in psoriatic skin lesions before and after treatment. Results Significantly increased expression of four adhesion molecules was found in psoriatic skin lesions (P<0.005). Significantly increased serum levels of ICAM-1, ICAM-3, ELAM and VCAM-1 were also found in psoriatic patients as compared to those in healthy controls (P<0.001). Serum levels of these adhesion molecules were significantly decreased after treatment. A significant reduction of expression of ICAM-1, ICAM-3, ELAM and VCAM-1 was noted on dermal vascular endothelial cells and infiltrating leukocytes after treatment (P<0.005). Serum levels of these adhesion molecules were positively correlated to clinical severity of psoriasis assessed by psoriasis area severity index (PASI). Moreover, as compared to other adhesion molecules, VCAM-1 was found to be most significantly increased in sera of patients with psoriasis and to be most significantly correlated to PASI score of the patients. Conclusions The present data suggest that both serum and lesional adhesion molecules be involved in psoriatic inflammatory process. Elevated serum adhesion molecules may be due to the results of shedding off the corresponding adhesion molecules into the blood stream from activated endothelial cells in lesional area of psoriatic patients. Among the four adhesion molecules investigated, VCAM-1 serum level is a novel sensitive marker of monitoring disease activity in psoriatic patients.

Key words: Cell adhesion molecules, Psoriasis