Early events in ultraviolet light-induced skin lesions in lupus erythematosus: expression patterns of adhesion molecules ICAM-1, VCAM-1 and E-selectin.

In our previous study, photoprovocation induced lupus erythematosus (LE) and polymorphous light eruption-like lesions in photosensitive LE patients. In this new study we examined the expression of ICAM-1, VCAM-1 and E-selectin, in early lesions in particular. A total of 32 patients with cutaneous LE, 25 with "classic" discoid LE, and 7 with systemic LE, including 3 patients with subacute cutaneous LE, were provoked with UVA and UVB on normal appearing skin. Induced lesions were followed up with serial biopsies. LE-like histopathology was seen within 1 week of provocation in some cases. Adhesion molecule expression was statistically significantly affected by the factors clinical diagnosis and wavelength (UVA or UVB). Strong keratinocyte ICAM-1 expression was found 1 week after provocation in reactions that eventually developed into long-standing ones. It is possible that these early changes reflect an underlying defect in the mechanisms that regulate adhesion molecule expression in LE.