Experimental Approaches on Tissue Engineering Repair of Peripheral Nerve Gaps

Peripheral nerve research is highly dynamic and a current major focus is the development of cell based supportive therapies as well as bioengineered nerve conduits to overcome the challenges in reconstructing long peripheral nerve defects. Whenever primary nerve repair cannot be performed without regeneration impairing tension at the suture sites, autologous nerve grafting or nerve tubulization are standard surgical repair techniques. However, functional recovery after severe nerve lesions is generally partial and unsatisfactory. Furthermore, nerve grafting is accompanied with several disadvantages. Autologous nerve material is only of limited availability as it has to be withdrawn from a healthy sensory nerve during an extra surgical incision that commonly results in sensory residual deficits. Reconstruction of long nerve defects remains a challenge since the gold standard of autologous nerve grafting as well as transplantation of clinically approved artificial resorbable nerve conduits result in a success rate of approximately 69% for nerve defects not exceeding a length of 3 cm only. This chapter reviews basic science studies from several laboratories evaluating tissue engineering nerve repair strategies especially with regard to the cellular and molecular composition of artificial nerve grafts. The possibility to attach Schwann cells or Schwann cell-like cells to biodegradable nerve guides for cellular support of the regeneration processes or for ex vivo gene therapy is of similar interest as the opportunity to functionalize the biomaterial with bioactive molecules through physicochemical modification or to allow long term release of regeneration promoting molecules during biodegradation. Peripheral nerve * Corresponding author: Kirsten Haastert-Talini: Hannover Medical School, Institute of Neuroanatomy, D-30623 Hannover, Germany, Email: [email protected], Tel: 0049-511-532-2891; Fax: 0049-511-5322880 The exclusive license for this PDF is limited to personal website use only. No part of this digital document may be reproduced, stored in a retrieval system or transmitted commercially in any form or by any means. The publisher has taken reasonable care in the preparation of this digital document, but makes no expressed or implied warranty of any kind and assumes no responsibility for any errors or omissions. No liability is assumed for incidental or consequential damages in connection with or arising out of information contained herein. This digital document is sold with the clear understanding that the publisher is not engaged in rendering legal, medical or any other professional services. Kirsten Haastert-Talini 210 tissue engineering holds promise to provide future support and orchestration of regeneration processes across long nerve gaps to a similar or even higher extend an autologous nerve graft does today.