Expression of intercellular adhesion molecule-1 (ICAM-1) and OKM5 in UVA- and UVB-induced lesions in patients with lupus erythematosus and polymorphous light eruption.

Pathological skin reactions were induced with both UVA and UVB in 12 patients with lupus erythematosus (LE) and with UVA in 7 with polymorphous light eruption (PMLE) but in none of the controls. Biopsy specimens taken from UV-induced lesions showed that in dermal infiltrates of LE cases CD4-positive cells predominated, whereas in the majority of PMLE cases CD8-positive cells predominated. Keratinocytes expressed intercellular adhesion molecule-1 (ICAM-1) in 7 of the 12 UVA- and in eight of the ten UVB-induced LE lesions, and in three of the UVA-induced lesions of PMLE patients. Three different staining patterns were found. In subacute cutaneous LE (SCLE) cases staining throughout the epidermis resembled that seen in genuine SCLE lesions. In discoid LE (DLE) lesions, the staining was most prominent in and near the basal cell layer. In the one systemic LE case and in the PMLE cases, ICAM-1 expression was seen only in association with epidermal spongiosis and T-cell infiltration. Keratinocytes did not express ICAM-1 in the controls or in the non-irradiated skin of the LE patients. In five on the UVA-induced lesions, in eight of the UVB-induced LE lesions and in one of the PMLE cases, keratinocytes expressed CD36. In four of the six LE lesions with fewer CD1a-positive cells, dendritic CD36-positive cells were seen in the epidermis. In conclusion, the pattern of activated keratinocytes and immunocompetent cells in the dermis was similar to that seen in genuine LE and PMLE lesions, but dissimilar to each other and to the controls.(ABSTRACT TRUNCATED AT 250 WORDS)