Differential endothelial adhesion molecule expression in early and late whealing reactions

In order to clarify the pathomechanisms of fleeting versus more persistent wheals, expression of endothelial adhesion molecules was studied in biopsies of lesional and uninvolved skin of 15 patients with different types of whealing reactions, using immunohistochemistry. In wheals of less than or equal to 30 mill duration, no increase of ELAM-1 and ICAM-1 was noted. GMP-140 expression was absent in prick tests. but could be demonstrated in lesions of cholinergic and cold urticaria, with a gradual increase of the latter with time. In wheals of greater than or equal to 6 h duration, GMP-140 was only weakly expressed whereas ELAM-1 and ICAM-1 were markedly upregulated in lesional and less so in nonlesional skill of acute, chronic recurrent and delayed pressure urticaria. This differential expression of endothelial adhesion molecules may reflect the activity of mast cell-derived and other mediators during the elicitation phase and explains the persistence of wheals in different types of urticaria.