ICAM-1 and LFA-1 expressions in the lesional skin of annular erythema associated with Sjögren syndrome.

ICAM-1 and LFA-1 expression was studied in the lesional skin of ten cases of annular erythema associated with Sjögren syndrome. Most of the infiltrating mononuclear cells around blood vessels expressed LFA-1 in addition to its strong expression on vascular endothelial cells and focal expression on the epidermal basal cell layer in 3 cases. ICAM-1 expression on vascular endothelial cells was similar to LFA-1, although relatively focal and weak expression was observed on mononuclear cells. ICAM-1 expression on keratinocytes was focal and limited to the basal cell layer in annular erythema. These findings suggest that strong expression of ICAM-1 on endothelial cells but not keratinocytes and LFA-1 on mononuclear cells might play some role in the induction of skin lesions in annular erythema associated with Sjögren syndrome.