Increased expression of thymic stromal lymphopoietin receptor in a rat model of middle cerebral artery occlusion.

Thymic stromal lymphopoietin (TSLP) is an epithelial cell-derived cytokine expressed in the skin, gut, lungs, and thymus. TSLP triggers dendritic cell-mediated T helper 2 inflammatory responses by formation of a ternary complex consisting of a heterodimer of interleukin-7 (IL-7) receptor α chain (IL-7Rα), TSLP, and the TSLP receptor chain (TSLPR). The present study aimed to investigate the expression of this ternary complex and its interaction with signal transducer and activator of transcription 5 (STAT5) in a ischemic stroke model using middle cerebral artery occlusion. Using immunofluorescence staining, we found that TSLPR was expressed widely in neurons and gliocytes. Using immunoprecipitation analysis, we detected an increased interaction between STAT5 and the ternary complex in the cortex of stroke rats. Moreover, using western blots, we found that expressions of the ternary complex and STAT5 were markedly increased in the cortex of stroke rats compared with the control and sham rats. These results suggest that the formation of the ternary TSLPR : TSLP : IL-7Rα complex may activate STAT5 or a STAT5-related signaling pathway to mediate neuroinflammation in ischemic stroke.