In vitro characterization of a nanostructured fibrin agarose bio-artificial nerve substitute.

Neural tissue engineering is focused on the design of novel biocompatible substitutes to repair peripheral nerve injuries. In this paper we describe a nanostructured fibrin-agarose bioartificial nerve substitute (NFABNS), based on nanostructured fibrin-agarose hydrogels (FAHs) with human adipose-derived mesenchymal stem cells (HADMSCs). These NFABNSs were mechanically characterized and HADMSCs behaviour was evaluated using histological and ultrastructural techniques. Mechanical characterization showed that the NFABNSs were resistant, flexible and elastic, with a high deformation capability. Histological analyses carried out in vitro during 16 days revealed that the number of HADMSCs decreased over time, with a significant increase after 16 days. HADMSCs formed cell clusters and degraded the surrounding scaffold during this time; additionally, HADMSCs showed active cell proliferation and cytoskeletal remodelling, with a progressive synthesis of extracellular matrix molecules. Finally, this study demonstrated that it is possible to generate biologically active and mechanically stable tissue-like substitutes with specific dimensions, based on the use of HADMSCs, FAHs and a nanostructure technique. However, in vivo analyses are needed to demonstrate their potential usefulness in peripheral nerve repair.