A Prototype Instrument for Subretinal Transplantation of induced Pluripotent Stem (iPS) Cell-derived Retinal Pigment Epithelial Cell Sheets

Abstract

Purpose: : To develop surgical techniques and instruments for cell sheet transplantation into subretinal space.

Methods: : Retinal pigment epithelial (RPE) cells were derived from human induced pluripotent stem cells and RPE cell sheets were prepared by the expansion of picked-up induced pluripotent stem (iPS) cell-derived RPE cell colonies. The pneumatic balloon actuator (PBA) was made of polydimethylsiloxane (PDMS) membrane and driven by pneumatic pressure. Employing the principle of PBA, a 3 x 3mm square shaped actuator was retracted into the cylindrical shaped cannula of 2mm diameter. We fabricated a prototype instrument for subretinal transplantation with a cannula which RPE cell sheets could be rounded in a cylindrical shape and inserted into the eye. By using the instrument, we tried to perform sequential motions so as to insert and transplant RPE cell sheets into the subretinal space of monkey eyes.

Results: : By coating the surface of the actuator with gelatin gel, RPE cell sheets could be mounted on the actuator and retracted in the cannula. The actuator could be inserted into the eye through the cannula and expanded in the subretinal space. On the other hand, there were some difficulties to insert the cannula into the subretinal space and to release RPE cell sheets by the negative pressure of leaking intraocular fluid through the cannula.

Conclusions: : Transplantation of cell sheets into subretinal space needs the safe and stable technique to place the sheets keeping polarity of the RPE cells. We are improving the instrument for the safe and stable technique for RPE cell sheet transplantation.

Keywords: regeneration • retinal pigment epithelium • transplantation