Abstract
Abstract: :
Purpose: To determine the gene expression encoding for plasminogen activator inhibitor–1 (PAI–1), protein C and protein S in serum free cultured pigmented ciliary epithelial cells of the porcine eye and to detect PAI–1 activity and concentrations of protein C and S in cell culture supernatants. Methods:Total mRNA was extracted from confluent primary cultures of porcine pigmented ciliary epithelial cells, which were cultured under serum free conditions. Reverse transcribed mRNA of PAI–1, protein C and protein S was measured by real time polymerase chain reaction (TaqMan® PCR). In order to demonstrate that PAI–1, protein C and S may be produced and secreted by cultured porcine pigmented ciliary epithelial cells we additionally analyzed supernatants of cell cultures (n=16) by using an enzyme–linked immunosorbent assay (Asserachrom® Protein C, Protein C, Roche Diagnostics, Germany). The activity of PAI–1 in the cell culture supernatants (n=8) was measured by using a specific chromogenic test (Coatest® PAI–1, Chromogenix, Italy). Results: The mRNA of PAI–1, protein C and protein S was localized in cultured pigmented ciliary epithelial cells of the porcine eye. As a positive control we established total mRNA of Hep–G2 cells. The negative controls, mRNA of kidney cells, did not show any signal. PAI–1 activity were found in all samples of cell culture supernatants (20–36 AU/ml). However, we could not detect any concentration of protein C and S in the cell culture supernatants. Conclusions: Our results indicate that ciliary epithelial cells are able to produce and secrete PAI–1, which is a main regulator of the fibrinolytic system. We suggest that PAI–1 overproduction in the anterior segment of the eye may be involved in aequous outflow by reducing both fibrinolysis and degradation of extracellular matrix in aequous humor and trabecular meshwork. In addition, stimulation of PAI–1 production may be involved in intraocular inflammation and wound healing processes.
Keywords: gene/expression • ciliary body • wound healing