Loss of Stemness by Suppression of Kruppel-Like Factor 5 in Human Limbal Stem Cells = Loss of Stemness by Suppression of Kruppel-Like Factor 5 in Human Limbal Stem Cells

다국어 초록 (Multilingual Abstract)

The aim of this study is to investigate the role of endogenous Kruppel-like factor 5 (KLF5) in human limbal stem cells (hLSCs). The hLSCs were isolated from the corneoscleral rims of donors after corneal transplantation. Isolated cells were co-cultured with mitomycin-c (MMC)-treated fibroblasts. HLSCs were treated with siRNA directed against KLF5, and effects on stemness were analyzed using colony forming efficacy (CFE). ABCG2, OCT4 and P63 as markers of hLSCs, cytokeratin 3 (CK3) and E-cadherin as markers of differentiation were confirmed by RT-PCR, western blotting assay, immunocytochemistry. And corneal epithelialization of the limbal stem cells was confirmed by air-lift 3d-culture. The number of colony (larger than 1 mm in diameter) in KLF5 siRNA treated-group was observed lower than that of control groups (non-treated group and negative siRNA treated-group). And expression of PCNA, OCT4, ABCG2 and P63 were decreased by KLF5 siRNA treatment. On the other hand, expression of cyclin D1, CK3 and E-cadherin were increased in KLF5 siRNA treated-group. Additionally, the limbal stem cells with klf5 siRNA treatment had not formed multi-layers in air-lift 3d-culture. In this study, suppression of KLF5 expression in hLSCs induced the loss of their stemness. These results suggested that KLF5 is closely relative to proliferation and stemness of hLSCs in cornea.