The Expression Of CXCL11/I-TAC And Its Receptor CXCR3 In The Lesions Of Discoid Lupus Erythematosus

IntroductionChemokine is a class of lowmolecular weight proteins to attract leukocytes specifically, which can be divided into 4 subgroups:C, CC, CXC and CX3C, Chemokines play their roles by chemokine receptors (CR), which are expressed on their target cells'membranes. IFN-inducible T cell chemoattractant (CXCL11/I-TAC) is a type 1 chemokines (or Thl chemokines) which specifically chemoattracts CXCR3-expressing Thl or Tcl cells.The type 1 chemokines are overexpressed in Thl-dominated inflammatory skin diseases. Their main source is keratinocytes (KCs). In recent years, there have been increasing evidences that CXCL11/I-TAC is overexpressed in Thl-dominated skin disorders such as psoriasis and lichen planus. The expression of CXCL11/I-TAC and its receptor CXCR3 are detected in the lesions of 36 patients with discoid lupus erythematosus by immunohistochemical assay.Materials and Methods1. Materials(1) Cases and samples:All patients with discoid lupus erythematosus were diagnosed by clinical manifestations, pathology and direct immunofluorescence. Normal control skin samples were from plastic surgery patients.(2) Major reagents:Rabbit anti-human I-TAC polyclonal antibody and goat anti-human CXCR3 polyclonal antibody were from Santa Cruz, USA. Goat anti-rabbit streptavidin-peroxidase (SP) kits and rabbit anti-goat SP kits were from Zhongshan. 2. MethodsFrozen sections (5μm) were prepared from lesions of 36 patients with discoid lupus erythematosus. Normal control skin samples were prepared from 16 patients undergoing plastic surgery without dermatosis. Immunohistochemical assay was came out to detect the expression of CXCL11/I-TAC and CXCR3.ResultsThe expressions of CXCL11/I-TAC and CXCR3 were both significantly higher in discoid lupus erythematosus lesions than those in normal skins (P<0.01).ConclusionThe upregulated expression of type 1 chemokine CXCL11/I-TAC and its receptor CXCR3 in the lesions of discoid lupus erythematosus, a Thl-dominated skin diseases, indicates that CXCL11/I-TAC and CXCR3 play important roles in the pathogenesis of discoid lupus erythematosus.