Abstract
Purpose:
To evaluate a surgical technique for human induced pluripotent stem cell-derived retinal pigment epithelium (hiPSC-RPE) cell-sheet without artificial scaffold using a novel device.
Methods:
A novel device consisted of a processed flat 20-gauge cannula and a custom-made plunger. Subretinal transplantation of a 1.3 mm X 3.0 mm hiPSC-RPE cell-sheet was performed in 12 rabbits. Results were evaluated by graft condition (damaged or folded), settled side (correct or upside down), position (center, near, far), and direction (anterior, posterior, right, left) immediately after surgery and graft condition (shrunk or folded) 2 weeks after surgery with fundus photographs. The eyes were then fixed for histology. Besides, Subretinal transplantation of grafts in the medium with 50 % viscosity was performed in 8 rabbits.
Results:
All grafts could be transplanted without obvious damage. Among the 12 transplanted grafts, 2 were folded, 12 were settled with correct side, 12 were center positioned, 10 were shifted in anterior direction and 2 were in right direction immediately after surgery. However, by inserting the device co-axial to the direction of flow paths corrected the grafts direction (consecutive 9 of 9 grafts). Two weeks after surgery, 2 of 12 grafts were invisible, 2 were folded, and 4 were shrunk. All the grafts in 50 % viscosity medium ended up shrunk. Nevertheless, adequate drainage of subretinal fluid during surgery to help the adhesion of graft and host prevented grafts from shrinking (consecutive 4 of 4 grafts). Histology demonstrated that outer nuclear layer above the grafts were not significantly different from those around the grafted area.
Conclusions:
We presented a novel device to transplant hiPSC-RPE cells-sheet safely and stably with the correct positioning into subretinal space by inserting the grafts in the coaxial direction of flow paths and with adequate subretinal drainage. We will further confirm these results by transplanting hiPSC-RPE cell-sheet into monkey eyes.
Keywords: 701 retinal pigment epithelium •
741 transplantation •
762 vitreoretinal surgery