Identifying Markers to Determine Optimal Stage of Differentiation of Retinal Pigmented Epithelial Cells into Photoreceptors

According to the CDC, approximately 12 million people in the United States over the age of 40 suffer from vision impairment.7 Stem cell therapies have grown widely in popularity as treatment options for conditions of vision impairment.11 These therapies include differentiating stem cells into retinal pigmented epithelium (RPE) cells which are then transplanted into the epithelial layer that lines the back of the eye, the retina. Although there have been clinical trials using stem cell therapies to treat vision loss, various issues, such as the presence of off target cell types during the differentiation process, exist which require the refinement of these therapeutic techniques. Through this work, the goal was to determine various markers that were expressed at different stages of RPE differentiation from induced pluripotent stem cells (iPSCs). Using immunocytochemistry, markers that were expressed at specific timepoints of RPE differentiation from iPSCs were determined. By knowing what markers are expressed by RPEs during their development, the issues of mixed cultures can be avoided. Additionally, the most adequate seeding density to conduct the differentiation process based on the protocol that was used was determined, resulting in improved yields of RPE.