In allergic skin diseases such as atopic dermatitis (AD), eosinophils migrate from the circulation to the skin. We investigated the mechanisms of eosinophil chemotaxis in atopic dermatitis by examining the effect of stimulation of epidermal keratinocytes (KC) by inflammatory cytokines, interferon-gamma (IFNgamma) and/or tumor necrosis factor-alpha (TNF alpha) on the production of eosinophil chemotactic factors. Simultaneous addition of IFNgamma and TNF alpha to culture KC synergistically increased eosinophil chemotaxis and the expression of RANTES mRNA and protein level on these cells. Anti-RANTES antibody blocked eosinophil chemotaxis by IFNgamma- and TNF alpha-stimulated KC. Our results indicate that the production of RANTES by KC may help to explain eosinophil infiltration into the skin in AD.