Expressions of cell differentiation proteins and intercellular connectins in pinguecula epithelium

Objective To evaluate the expressions of cell differentiation proteins (K19 and K10), intercellular connectins (E-cadherin and β-catenin) in pinguecula epithelium. Methods Fifteen patients ( 15 eyes ) with pinguecula who underwent simple excision were enrolled in this study. K19, K10, E-cadherin and β-catenin expressions in pinguecula tissue were detected by immunofluorescence histochemistry staining method and compared with those in normal conjunctiva. Results E-cadherin and β-catenin expressed at low level (335.37±216.42, 1903.31±333.12) ;K19 expressed in whole conjunctival epithelium (25 792.08±14 260.50), while K10 was absent in normal conjunctival epithelium. In contrast, there were higher expressions of K10, E-cadherin and β-catenin (3242.45±3056.78, 2324.05±2598.64, 8979.97±3777.61 ), and lower or no expression of KI9 (5995.64±5140.48)in pinguecula epithelium. Compared with normal conjunctiva, the absorbance (A value) of K10, K19, E-cadherin and β-catenin expressions were significantly different in pinguecula epithelium (P< 0.05). Conclusion Abnormal expressions of K10, K19, E-cadherin and β-catenin in pinguecula tissue are possibly involved in epithelial squamous metaplasia. Key words: Pinguecula; Connexins; Cell differentiation; Epithelial cells; Fluorescent antibody technique