Abstract
Purpose :
Very recently, the discovery of a class of molecules which could partially restore transparency in animal cataract models opened a new window for the treatment of cataracts. Therefore, to generate an in vitro model for the development of the human lens which could serve as a platform to test new therapeutic strategies for the treatment of cataract would be the priority for the further use of these molecules. Our group has generated functional lentoid bodies (LBs) using human induced pluripotent stem cells (hiPSCs) (unpublished data and presented in ARVO 2015), but whether the LB could model the human lens genesis is still unclear. Thus, this study is to investigate the similarity of the relative gene expression between the LB induction process and the lens development in vivo.
Methods :
LBs were generated using the established “fried egg” method. Degeneration of nucleus and organelles during the differentiation of lens fiber cells was investigated through transmission electron microscropy (TEM). Lens development- and autophagy-specific gene expression levels and their temporal distribution patterns were evaluated among cell samples on Day0 (D0), D7, D14, D25 of LB generation process by microarray data analysis and real-time PCR. The expression of selected lens and autophagy markers was further analyzed by immunofluorescence examination and/or western blot.
Results :
The “fried egg” method for LB induction was named after the cell clusters which showed “fried egg” morphology on D11. Degeneration of nucleus and organelles accompanied with autophagosomes was observed in both unmature and mature LBs. During LB induction process, the placodal markers such as SIX3 and DLX3 were first detected when epithelial-like cells were able to be distinguished from the other cells. Then, the expression of early lens markers such as SOX1, PAX6 and PROX1 started to be observed when the cell clusters with “fried egg” morphology appeared, so as the other lens development-specific genes such as MAB21L2, CDH2, MEIS1 and MAF. Moreover, the autophagy-specific markers such as LC3B, ATG5, VMP1 were highly expressed in the cells at the stage of fiber cell differentiation.
Conclusions :
Our study provides the evidence toward the gene expression profile of the LBs derived from hiPSCs, thereby established an in vitro model for the development of the human lens.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.