Thymic stromal lymphopoietin

Thymic stromal lymphopoietin (TSLP) is an epithelial cell derived cytokine expressed in skin, gut, lungs and thymus. TSLP signals via TSLPR, a heterodimer of the IL-7 receptor alpha chain (IL-7Rα) and the TSLP receptor chain (TSLPR), which is closely related to the common receptor-γ chain (γc), expressed on a wide range of cell types in the adptaive and innate immune system. TSLP exerts profound influence on the polarization of dendritic cells (DCs) to drive T helper (Th) 2 cytokine production. It also directly promotes T cell proliferation in response to T cell receptor (TCR) activation, and Th2 cytokine production. TSLP also supports B cell expansion and differentiation. TSLP further amplifies Th2 cytokine production by mast cells and NKT cells. These properties confer on TSLP a critical role in driving Th2 mediated inflammation. This role is supported by the finding that TSLP expression is up-regulated in keratinocytes of atopic dermatitis (AD) skin lesions and in bronchial epithelial cells in asthma