A proper protocol for isolation of retinal pigment epithelium from rabbit eyes

BACKGROUND: Retinal pigment epithelium (RPE) is a hexagonal monolayer of pigmented cells located between the neural retina and the choroid with an essential role for visual function. So, isolation, propagation and maintenance of their functional integrity of RPE are crucial for research in vitro which next used for cell transplantation. The evaluation of features of RPE cells as a sheet after 14 days has not been reported yet. This study aimed to examine and compare three protocols for RPE isolation from rabbit eyes and obtain a proper protocol, which illustrated isolated RPE cells as a sheet cause to preserve their characterize even after 2 weeks. MATERIALS AND METHODS: RPE cells were prepared from eyes of 24 rabbit eyes. After enucleating of eyes, anterior segment discarded and posterior segment cut to small pieces. Two of these procedures are based on the enzymatic digestion, but third protocol based on mechanical dissection. The culture cells harvested and morphological feature of cells assessed by phase-contrast microscope and then analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR) and immunocytochemistry. RESULTS: Evaluation of morphological feature showed that isolation of RPE cells as a sheet lead to preserve their hexagonal morphology. Immunocytochemistry and RT-PCR assessment demonstrated RPE cell cultured in sheet maintained their phenotypic feature, tight junction and the distribution of actin and cytokeratin filament. Comparison of three protocols showed that dissociation of RPE cells as a sheet was superior in the preserve of RPE characteristic. CONCLUSIONS: Isolation of RPE cells as a sheet maintains the integrity of these cells, this procedure promising a therapeutic approach, which is important for some retinal diseases.