Effects of topically applied glucocorticosteroids on patch test responses and recruitment of inflammatory cells in allergic contact dermatitis.

The effects of repeated topical application of a strong glucocorticosteroid (GCS) on patch test responses and the inflammatory infiltrate were studied in twenty nickel allergic patients. Patch test responses were strongly inhibited in 18 out of 20 patients. Immunohistochemical analysis revealed marked reductions in CD1+(T6+) Langerhans cells, activated inflammatory T cells and of mast cells in the skin. It is concluded that GCS suppress contact allergic responses by reduction, or functional inhibition of antigen presenting cells. The reduced number of mast cells release less vasoactive mediators, inhibiting recruitment of inflammatory cells.