Abstract
Abstract: :
Purpose: It has been suggested that human ß-defensin (HBD) plays a role in the defense against microbial infection, and it has recently been shown that the cornea produces HBDs. We have reported that dexamethasone reduce HBD-1 mRNA expression in corneal epithelial cells. In this series of experiments, we wished to examine the effects of cyclosporin A, which is clinically often administered as immunosuppressive agaents, on mRNA expression of HBDs by corneal epithelial cells in vitro. Methods: Corneal epithelial cells from an immortalized corneal epithelial cell line (SV40) were cultured at a concentration of 6×104 cells/cm2 in culture medium (SHEM medium) in 6 well dish. After 72hrs, when the cultures reached confluence, cells were harvested and total RNA was extracted. Using semi-quantitive PCR and competitive PCR, HBD-1 and HBD-2 mRNA expression were examined. In some cultures, dexamethasone (10-5, 10-7M) or cyclosporin A (1, 10-1 mg/l) was added to the cultures at 48 hours. The level of HBDs mRNA expression by corneal epithelium cultured with or without dexamethasone or cyclosporin A was analyzed by both semi-quantitive PCR which is a conventional method and introduced amplified fragment length polymorphism (iAFLP) which is a more exact method. Results: Semi-quantitive PCR and iAFLP revealed that dexamethasone suppressed only HBD-1 mRNA expression in corneal epithelial cells in a dose-dependent manner, however cyclosporin A suppressed only HBD-2 mRNA expression in corneal epithelial cells in a dose-dependent manner. Conclusion: These results suggest that the regulations of HBD-1 and HBD-2 are completely deferent between dexamethasone and cysclosporin A. We imply that ocular surface defensive abilities against bacterial infection may differ between the administration of dexamethasone and cyclosporine A.
Keywords: 372 cornea: epithelium