Proliferation, multipotency and neuronal differentiation of cryopreserved neural progenitor cells derived from the olfactory neuroepithelium of the adult rat.

The use of olfactory neuroepithelium neural progenitor cells for transplantation has attracted attention in the treatment of many neurological disorders, which require efficient recovery methods and cryopreservation procedures. The purpose of this study was to evaluate different cryopreservation techniques for neural progenitor cells derived from the olfactory neuroepithelium (ONe NPCs) in adult rats. Initially, we compared the survival rates of cryopreserved ONe NPCs treated with six different cryoprotectants: dimethylsulfoxide (DMSO), ethylene glycol (EG) and glycerol, each with or without 10% FBS and with two different storage periods in liquid nitrogen (-196 degrees C), specifically 3 days short-term storage and 3 months long-term storage. We assessed the recovery efficiency of ONe NPCs after freezing and thawing by viability testing and colony-forming assay as well as immunocytochemistry under different conditions. No significant difference in the survival rate was observed among these different cryoprotectants. With these protocols, ONe NPCs retained their multipotency and differentiated into glial (GFAP-positive), neuronal (NeuN-positive) and oligodendroglia (Galc-positive) cells. Collectively, our results imply that, under optimal conditions, ONe NPCs might be cryopreserved for periods of >3 months without losing their proliferative and multipotency activities.