Epicutaneous immunization with hapten-conjugated protein antigen alleviates contact sensitivity mediated by three different types of effector cells

Allergic contact dermatitis (ACD) is a common clinical condition in industrialized countries and often causes occupational diseases. Animal model of contact sensitivity (CS) is commonly used to study ACD in mice and can be induced by skin application of haptens. It has been previously shown that CS is mediated by CD4+ or CD8+ T effector cells. More recently it was found that also liver NK cells can play a role of CS effector cells in mice. The aim of the present study was to test whether skin-induced suppression could inhibit CS response in vivo. Here we show that EC immunization of normal mice with hapten conjugated protein antigen prior to hapten sensitization suppresses Th1, Tc1 and NK mediated CS responses. These data strongly suggest that maneuver of EC immunization may have important implications for designing therapeutic schemes aimed at modulating unwanted immune responses in contact hypersensitivity.