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[Cryopreservation and resuscitation of neural stem cells from fetal rat].

OBJECTIVE
To explore the survival rate of neural stem cells (NSCs) from fetal rat and its biological properties after cryopreservation and thawing.


METHOD
Different generations NSCs (the first generation, the third generation and the sixth generation) from fetal rat which cultivated with serum-free medium in vitro were cryopreserved in the cryogen, which were neurosphere culture medium with 10% BSA and 7.5% DMSO (without neural growth factor). The cryopreserved cells were resuscitated at 1st week, 4th week, 8th week, 12th week and 16th week respectively. The survival rate of cells were calculated and the cells were incubated and differentiated again.


RESULT
Different time of cryopreservation, different generations did not affect NSCs survival (P > 0.05) after cryopreservation. The survival rate of NSCs was from 60% to 70% after resuscitated, which were differentiated into neurons and astrocytes in 10% embryonic bovine serum (without growth factor).


CONCLUSION
NSCs were successfully cryopreserved, resuscitated and recultured, which would create bases for the experimental study on the selected-date application of NSCs transplantation into cochlea for treating sensorineural deafness.