The Research On TLR Signaling Pathways On Pathogenesis Of Dry Eye Disease

Objective: To investigate the corneal expression of toll-like receptor (TLR)4anddetermine its contribution to the immunopathogenesis of dry eye disease (DED).Methods:7to8-week-old female C57BL/6mice were housed in a controlledenvironment chamber. Randomly divided into3groups: normal group, TLR4inhibition group and DED group.The expression of TLR4by the corneal epitheliumwas evaluated using reverse transcription PCR and Immunohistochemicalstaining.The expression of proinflammatory cytokines (IL-1β, IL-6, TNF) by thecorneal epithelium was evaluated using ELISA. Corneal fluorescein staining (CFS)was performed to evaluate clinical disease severity.Result:(1) The epithelial cells of normal corneas expressed TLR4intracellularly.(2)DED significantly increased the cell surface expression of TLR4.(3) TLR4inhibition decreased the severity of CFS and significantly reduced themRNA expression of IL-1β, IL-6, and TNF.Conclusion: These results suggest that DED increases the corneal expression ofTLR4and that TLR4participates in the inflammatory response to DED...