Abstract
Purpose :
To evaluate the differentiation efficiency of umbilical endothelial progenitor cells (UVEPCs) towards corneal endothelial cells (CECs) under the induction of the ROCK inhibitor Y-27632, and determine the most effective scheme to repair a rabbit corneal endothelium injury model.
Methods :
UVEPCs were cultured in EGM-2 medium, or in conditioned medium (CM) of human CECs, with or without Y-27632. BrdU staining and CCK8 assay were used to examine the cellular proliferation. Western blot and real-time PCR were used to detect the expression of CEC markers. The corneal endothelia of New Zealand white rabbits were treated with an Nd: YAG laser in a uniformly scattered fashion to establish the corneal endothelium injury model. Group A was injected with 100 μl Media (Opti-MEM I Reduced Serum Media) into the anterior chamber; Group B was injected with 100 μM Y-27632 diluted in Media; a total of 2 x 105UVEPCs supplemented with 100 μM Y-27632 (final volume, 100 μl) were injected into the anterior chamber of Group C. During the follow up, slit-lamp biomicroscopy, and optical coherence tomography were performed to evaluate wound-healing status.
Results :
Compared to the EGM-2 medium and CM, UVEPCs cultured in CM supplemented with 10 μM Y-27632 exhibited higher proliferation ability, and significantly improved protein level of N-Cadherin, Na+-K+-ATPase α1, Na+-K+-ATPase β1, and Pax6, as well as improved mRNA level of COL4A2, COL8A2, and AQP1. After 6 weeks of repairing, the corneal thickness of Group C (UVEPC with Y-27632) declined to the normal level, and the slit lamp examination revealed transparent cornea. The cornea thickness of Group B (Y-27632) significantly decreased compared to Group A (Media), but still is significantly thicker than Group C. The slit lamp examination revealed mild corneal nebula of group B, and moderate corneal opacity of group A.
Conclusions :
Y-27632 not only promotes the proliferation of UVEPCs, but also contributes to the differentiation of UVEPCs to CECs in CM. Y-27632 intracameral injection alone promoted the corneal endothelium wound healing, an on this basis, UVEPC supplemented with Y-27632 accelerated the healing process.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.