FIG. 5.

Tumorogenicity of bioreactor-differentiated cells. (A) Undifferentiated embryonic stem cells (ESCs) from static or suspension bioreactors form teratomas 18 days post-injection into a SCID mouse. (B) The frequency of teratoma formation diminishes rapidly when ESCs are differentiated in static culture but not in bioreactor culture systems. Excessive mineralization resulted in limited ability to collect the cells for the assay and these samples could therefore not be analyzed. These samples are noted in the table as N/A. (C) Representative sections of teratomas generated from ESCs that were differentiated for 30 days in either untreated, osteogenic, or chondrogenic bioreactor cultures, stained with H&E.