Engineered neural tissue for peripheral nerve repair

A new combination of tissue engineering techniques provides a simple and effective method for building aligned cellular biomaterials. Self-alignment of Schwann cells within a tethered type-1 collagen matrix, followed by removal of interstitial fluid produces a stable tissue-like biomaterial that recreates the aligned cellular and extracellular matrix architecture associated with nerve grafts. Sheets of this engineered neural tissue supported and directed neuronal growth in a co-culture model, and initial in vivo tests showed that a device containing rods of rolled-up sheets could support neuronal growth during rat sciatic nerve repair (5 mm gap). Further testing of this device for repair of a critical-sized 15 mm gap showed that, at 8 weeks, engineered neural tissue had supported robust neuronal regeneration across the gap. This is, therefore, a useful new approach for generating anisotropic engineered tissues, and it can be used with Schwann cells to fabricate artificial neural tissue for peripheral nerve repair. (C) 2013 Elsevier Ltd. All rights reserved.