Abstract
Purpose :
We have previously reported that, in the in vitro corneal wound healing model using mouse corneal epithelial cell line, epidermal growth factor (EGF) promoted re-epithelialization of denuded area, and that the re-epithelialization did not depend on cell proliferation. The purpose of this study was to investigate which downstream signal pathway, MAP kinase pathway or phosphatidyl inositol 3 (PI3) kinase pathway, is involved in this re-epithelialization.
Methods :
Corneal epithelial cell line TKE-2 was cultured and multilayered cultures were scratch-wounded with P10 pipette tip. Either EGF receptor kinase inhibitor AG1478 (2.5μM), MAP kinase kinase inhibitor PD08059 (20μM), PI3 kinase inhibitor LY294002 (50μM), or Wortmannin (5μM) was added to the culture and decrease of denuded area was evaluated. ImageJ software was used for the measurement of the area. Cell proliferation was evaluated by BrdU uptake and cell death by colorimetric analyses of lactate dehydrogenase in proliferating cell cultures.
Results :
When EGF receptor kinase inhibitor AG1478 was added, re-epithelialization was completely inhibited, while inhibition of re-epithelialization by MAP kinase kinase inhibitor PD08059 was mild. Similar to AG1478, two PI3 kinase inhibitors LY294002 and Wortmannin inhibited re-epithelialization completely. Under the administration of these inhibitors to proliferating cells, BrdU uptake was suppressed compared with control, while levels of cell death were not significantly different.
Conclusions :
For the re-epithelialization of denuded area, PI3 kinase pathway is the main pathway of the downstream of EGF receptor.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.