Traumatic injuries resulting in peripheral nerve lesions often require a graft to bridge the gap. Although autologous nerve auto-graft is still the first choice strategy in reconstructions, it has the severe disadvantage of the sacrifice of a functional nerve. Cell transplantation in a bioartificial conduit is an alternative strategy to create a favorable environment for nerve regeneration. We decided to test fibrin as a new conduit material after injury of the sciatic nerve. Conduits were tested both empty and in combination with different kind of regenerative cells such as Schwann cells (SC), mesenchymal (MSC) and adipose-derived stem cells (ASC), differentiated into a Schwann cell phenotype. Each group was composed by 5 animals for a total of 4 different groups (n = 20). At 2 weeks after implantation, conduits were explanted and examined by immunohistochemistry: axonal sprouting was evaluated by PGP 9.5 marker and Schwann cell presence was detected proximally and distally by S100 marker.
The results show a significant increase in axonal regeneration in the group fibrin seeded with SC compared with the empty fibrin conduit. Differentiated ASC showed a positive tendency in regeneration distance, comparable with the differentiated MSC.
These observations seem to strengthen the argument that SC can help in enhancing nerve regeneration when seeded in a conduit. Similarly, the interesting outcomes obtained from the dASC, which appear comparable to the dMSC, underline the effectiveness of this cell population and their promising applications in nerve regeneration.