Abstract
Abstract: :
Purpose: Retinal and iris pigment epithelial (RPE and IPE) cells undergo significant changes in cell morphology, cell function and differentiation when cultured, especially if they are passaged a number of times. Such changes, especially functional changes, may adversely influence the outcome if these cells are used for transplantation. It is therefore essential that, once isolated, these cells be maintained in a "native" state, that is viable and without undergoing de-differentiative changes. Since between isolation and transplantation there may be a significant delay, the aim of this study was to devise procedures for maintaining RPE and IPE in a "native" state for an extended period of time. Methods: Freshly isolated RPE cells were transferred in suspension into eppendorf tubes coated with silicone oil, pelletted and stored under various conditions. Viability was assessed at 4 hours and 24 hours in 96 well plates (10.000 cells/well) by a WST (WST-1 2-(4-lodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfonphenyl)-2H-tetrazolium) assay. Each individual test was performed in triplicate. Results: RPE cells kept in a pellet in phosphate buffered saline at 37°C for a minimum of 24 hours were shown to remain functional under maintenance of cell viability. Conclusion: Pigment epithelial cells can be maintained in suspension for up to 24 hours in phospate buffered saline, without a significant loss of viability. These results indicate that it is possible to maintain pigment epithelial cells without culturing them for at least 24 hours without the loss of viability.
Keywords: 567 retinal pigment epithelium • 607 transplantation