Role of Histamine on Itch Sensation Induced by Interleukin-31

Abstract

Chronic allergic dermatitis, including atopic dermatitis and chronic allergic contact dermatitis, is characterized by an itch sensation and eczematous lesions, along with T helper (Th) 2 cell and granulocyte infiltration. Th2 cells, mast cells and eosinophils secrete interleukin (IL)-31, inducing intense itching in allergic dermatitis. Regulatory T cells (Tregs) inhibit the infiltration of these cells. Histamine induces the development of eczematous lesions in patients with chronic allergic dermatitis. In these eczematous lesions, histamine induces cell infiltration and inhibits Treg infiltration via histamine H1 and H4 receptors. Therefore, histamine may aggravate the itch sensation during chronic allergic dermatitis by increasing IL-31 levels.