Effects of Human Serum on Human Corneal Epithelial Cells in Vitro

ABSTRACT

PURPOSE: To investigate the effect of human serum on corneal epithelial cells. METHODS: Changes of corneal epithelial cells were evaluated after 1, 4, 12, and 24 hours (hrs) of exposure to various concentrations of human serum (3, 5, 8, and 16%). Cellular metabolic activity and the extent of cellular damage were measured. Effect of human serum on cell migration was also examined. Concentration of procollagen type-I COOH-terminal peptide (PIP), epidermal growth factor (EGF), and laminin after exposure to human serum was further observed. RESULTS: In every concentration of human serum, metabolic activity of the corneal epithelial cells temporarily decreased at 4 hrs of exposure and recovered to baseline levels afterward. With the same exposure time, there was no statistically significant difference in metabolic activity between the human serum-exposed group and the control group. Cellular toxicity of human serum exhibited a time- and dose-dependent relationship. Cellular migration was observed after 24 hrs of exposure to 5% concentration of human serum and after 12 hrs of exposure to 8% and 16% concentration of human serum. The PIP, EGF, and laminin titers increased in time- and dose-dependent manners. CONCLUSIONS: Human serum does not decrease the metabolic activity of corneal epithelial cells as the concentration and exposure time increase, but it can induce cytotoxicity. Considering cellular migration, a serum concentration of 5% or higher should be used.