Poly lactic acid-caprolactone copolymer tube with a denatured skeletal muscle segment inside as a guide for peripheral nerve regeneration: A morphological and electrophysiological evaluation of the regenerated nerves

Abstract

A biodegradable copolymer of poly L-lactic acid and epsilon-caprolactone (PLAC) was manufactured into a tube, in which a denatured skeletal muscle segment was placed longitudinally. This model tube was implanted as a guide to promote nerve regeneration across a 5 cm gap in the rabbit sciatic nerve. Five months after implantation, good nerve regeneration was found throughout the graft and in the distal host nerve. The population (29.6/16 x 10(2) microm(2)) of regenerated nerves in the graft was higher than that of the contralateral normal sciatic nerve (18.0/16 x 10(2) microm(2)). Regenerated nerve fibers extended to the distal host nerve. The number of myelinated fibers was 13.7/16 x 10(2) microm(2) at a level 1.5 cm from the distal suture. The diameters (below 2 microm) of most regenerated myelinated (nerves in the graft and in the distal host nerve were much smaller than those (6-8 microm) of normal nerves. Electrophysiological evaluation showed that the hindlimb muscle (gastrocnemius) was innervated by motor nerves in all animals 5 months after implantation. These results indicate that the PLAC tube with a denatured muscle segment inside provided good conditions for nerve fiber regrowth. The PLAC tube is thought to protect the denatured muscle segment from rapid dissociation in the host tissue.

Electrophysiologic and Functional Evaluations of Regenerated Facial Nerve Defects with a Tube Containing Dental Pulp Cells in Rats

“…These results were quite consistent with those of previous reports that regenerated nerve has immature myelin sheath, slower conduction velocity, and larger compound muscle action potential latency compared with intact or autografted nerve. [41][42][43] Therefore, it might take longer than 13 weeks to observe sufficient recovery of the conduction velocity of regenerated facial nerve, even with dental pulp cells.…”

Intra-thoracic fibrous tissue induction by polylactic acid and epsilon-caprolactone copolymer cubes, with or without slow release of basic fibroblast growth factor

“…The cubes fabricated from the PLAC were biodegradable, permeable, and biocompatible. This material is widely used as a scaffold for nerve regeneration [18][19][20][21].…”

First human experience with autologous Schwann cells to supplement sciatic nerve repair: report of 2 cases with long-term follow-up

“…Although initial reports focused on short gap repairs, 5,18,26 several substrates have been studied for their potential to heal large gap defects when supplemented with AGCs, including purified SCs. 1,6,7,9,11,12,16,17,27,28,34,37,38,[40][41][42]44 Berrocal et al demonstrated that adding autologous SCs suspended in serum to AGCs significantly enhanced the ability to bridge larger gap distances in sciatic nerve repair in rats. 3 Autologous SCs can be harvested from either a donor nerve or from the epicenter of the traumatized nerve ends in sharp injuries (propeller injury, gunshot wound, stab wound).…”