Effect of pulsed dye laser on intercellular adhesion molecule-1 (ICAM-1) expression after treatment of psoriasis

Abstract

Background

Intercellular adhesion molecule-1 (ICAM-1) is a member of the immunoglobulin super family of adhesion molecules that plays a role in transendothelial migration and adhesion processes involved in the pathogenesis of psoriasis. Previous studies have demonstrated partial and total clearance of psoriasis by selective photothermolysis of dermal vessels with the pulsed dye laser.

Objective

The aim of this study is to assess the efficacy of the pulsed dye laser (PDL) in treatment of chronic psoriatic plaque lesions by measuring changes in ICAM-1 expression in the epidermis and dermis of psoriatic patients before, during and after treatment, with correlation to the clinical improvement.

Patients and methods

Sixty patients with chronic plaque psoriasis were treated with flashlamp-pumped pulsed dye laser (FPDL) with 585 nm wavelength, 450 μs pulse duration, 7–8.5 J/cm² fluence, and 7 mm spot size. Sessions were performed every 2 weeks with each patient receiving a total of 3 sessions. Clinical, histological, and immunohistochemical assessments were carried out. A correlation between plaque severity score (sum score) and changes in the mean of ICAM-1 expression was assessed throughout and after treatment.

Results

Reduction of ICAM-1 expression mean in psoriatic lesion was 1.83 ± 0.29 at week 2, 1.60 ± 0.19 at week 4, and 1.53 ± 0.18 at week 6 from the start of the laser treatment, compared to the baseline which was 2.90 ± 0.40. In the control group, ICAM-1 expression was 0.60 ± 0.07. A significant correlation between clinical improvement and reduction in ICAM-1 expression at weeks 4 and 6 of laser treatment was proven (p < 0.05).

Conclusion

ICAM-1 expression is reduced significantly after treatment of psoriasis with pulsed dye laser, which can be used as an indicator for its efficacy.