Effect of cryopreservation on proliferative features of neural progenitor cells derived from olfactory bulb of embryonic rat

Objective: Stem cell research offers unique opportunities for developing new medical therapies for devastating diseases and a new way to explore fundamental questions of biology. The use of olfactory bulb neural progenitor cells for transplantation requires efficient recovery methods and cryopreservation procedures. The purpose of this study was to determine cryopreservation techniques for neural progenitor cells derived from olfactory bulb (OB NPCs) of embryonic rat. Methods: Initially, we compared the survival rates of cryopreserved OB NPCs using three cryoprotectants: dimethyl sulfoxide (DMSO), ethylene glycol (EG) and glycerol with or without 10% FBS. Cells were held at liquid nitrogen (-186 degrees C) for 7 days ("short-term storage") or 6 months ("long-term storage"). We assessed OB NPCs recovery efficiency after freezing and thawing by viability testing, colony-forming ability and immunocytochemistry under different conditions. Results: The survival rate of cryopreserved-thawed OB NPCs was estimated by counting colony numbers under a stereomicroscope. No significant difference in survival rate was observed between cryoprotectants. Conclusions: These observations indicate that cryopreservation of OB NPCs is possible for up to 6 months in optimal conditions without losing proliferation activity. (C) 2009 Elsevier Ireland Ltd. All rights reserved.