Histamine H4 Receptor in Allergic Dermatitis

Abstract

Allergic dermatitis, the common skin disease, includes chronic allergic contact dermatitis (CACD) and atopic dermatitis (AD), the Th2 dominant diseases. Histamine aggravates CACD in mice. Histamine H4 receptor (HH4R) is expressed on eosinophils, mast cells, T cells, natural killer cells, antigen presenting cells, basophils, keratinocytes and sensory neurons and is suggested to be related to allergic dermatitis. Administration of the HH4R antagonist JNJ7777120 is effective to the murine CACD models. Furthermore, combination of JNJ7777120 and the histamine H1 receptor antagonist olopatadine hydrochloride is a potent therapeutic target in chronic inflammatory skin diseases such as CACD and AD, since combined therapy is more effective than monotherapy.