P174 - The selective removal method of undifferentiated iPS cells using specific antibody for cartilage regenerative medicine.
Abstract
Purpose
Currently, a new option for repairing cartilage injury has become available by applying human iPS cells (hiPSCs), however, the tumorigenicity of residual hiPSCs is major concern. Hence, we verified the effects of new method to eliminate hiPSCs by using the iPS specific antibody “R-17F” which potentially has specific cytotoxicity toward them.
Methods and Materials
The binding ability of R-17F to hiPSC was evaluated using immunostaining. Cytotoxicity against hiPSC and chondrocyte (C28/I2) was evaluated by detecting the dead cells positive for PI staining by flow cytometry. Finally, to evaluate the selective cytotoxicity, R-17F was added after co-culturing hiPSC and C28/I2 fluorescently labeled respectively, cells were microscopically monitored at every 12h.
Results
Immunostaining by R-17F revealed its specific binding to hiPS colonies. In the evaluation of cytotoxicity, more than 70% of hiPSC were killed whereas the number of dead cells of C28/I2 was 15% that was almost equivalent to control (12%). Administration of R-17F to the mixing of chondrocytes and iPSCs diminished iPS colonies at 24 h whereas most of C28/I2 cells survived.
Conclusion
Our study revealed that the cell selection method using the R-17F antibody successfully eliminated iPSCs under the mixed condition with chondrocytes. This strategy will reduce the risk of the tumorigenicity of the iPS-derived cells before their transplantation.
