Different thawing methods for cryopreserved rabbit limbs: activity of Schwann cells after thawing

doi:10.3969/j.issn.2095-4344.2015.20.016

Abstract：BACKGROUND:According to the characteristics of nerve regeneration, the integrity of Schwann cels as regenerative scaffold is very important. Therefore, to save the Schwann cel structure and activity is most important for nerve cryopreservation. OBJECTIVE: To investigate the optimal thawing procedures for the survival of peripheral nerves in cryopreserved rabbit limbs. METHODS:Forty hindlimbs from New Zealand White rabbits were randomized into four groups: blank, fast-thawing, slow-thawing and control groups. The control group was subjected to perfusion with protective agent. The severed limbs in fast-thawing and slow-thawing groups were perfused with protective agent folowed by gradient cryopreservation and storage in liquid nitrogen for 72 hours. Then, the slow-thawing group was given gradient thawing procedures, and the fast-thawing group was subjected to fast thawing in 37℃ water bath. After thawing, the tibial nerves were harvested for light microscope, electron microscope, immunofluorescence and confocal microscope observation. SPSS17.0 was used for statistical analysis. RESULTS AND CONCLUSION:No significant difference was found between the blank and control groups. Nerve fiber breakage, axonal damage and mitochondrial sweling were severer in the fast-thawing and slow-thawing groups than the control and blank groups. In addition, the fast-thawing group was superior to the slow-thawing group. These findings indicate that the fast-thawing method has the minimal effects on the survival of nerve fibers in cryopreserved rabbit limbs.