Serum OX40 ligand: a potential marker of atopic dermatitis disease severity in children

INTRODUCTION The tumor necrosis factor receptor (TNFR) family consists of a number of type I transmembrane glycoproteins characterized by homologous cysteine-rich domains in their extracellular region. The intracellular parts of these proteins vary in size and structure, corresponding to the wide array of functions of TNFR proteins, ranging from regulation of cell activation and differentiation to induction of cell death. Twenty-two TNFR family members have been identified, including TNFR1, TNFR2, the low-affinity nerve growth factor receptor, CD27, CD30, CD40, CD95 (Fas), and CD134 (OX40). Except for the ligands of the lowaffinity nerve growth factor receptor, the ligands of TNFR proteins form the family of TNF-related proteins. Most TNF family members can be expressed as type II transmembrane receptors, and some of these proteins mediate signal transduction via their intracellular domain. Several members of the TNFR family (e.g., CD95, TNFR1, and TNFR2) and the TNF family (e.g., TNF-α, CD40 ligand, and CD95 ligand) can be produced as Original article