[Differential regulation of expression of PDGF receptors on corneal epithelial cells]

The function of platelet-derived growth factor (PDGF) during corneal wound healing is only incompletely understood to date. Previous studies have shown that the mRNA of PDGF receptor type alpha (PDGFR alpha) and type beta (PDGFR beta) is expressed in cultured corneal epithelial cells (CEP). To add to the current knowledge, the following study was designed to compare the expression of mRNA and protein of both PDGF receptor subtypes in cultured CEPs and in CEPs ex vivo.

Total RNA and protein were extracted from cultured CEPs and from CEPs ex vivo according to standard protocols. The reverse-transcription polymerase chain reaction (RT-PCR) was applied to detect specific expression of the mRNA of PDGFR alpha and PDGFRss. The expression of the corresponding proteins was detected using Western blotting.

MRNA and protein of both PDGF receptor subtypes could be detected in cultured CEPs but not in CEPs ex vivo.

The present study shows for the first time that mRNA and protein of both PDGF receptor subtypes are expressed in cultured human corneal epithelial cells, while corneal epithelial cells ex vivo do not express these receptors. The differential up-regulation of PDGF receptors in activated cells during wound healing could be of pathophysiological importance.