A human hair keratin hydrogel scaffold enhances median nerve regeneration in nonhuman primates: an electrophysiological and histological study

Tissue Eng Part A. 2014 Feb;20(3-4):507-17. doi: 10.1089/ten.TEA.2013.0084. Epub 2013 Nov 15.


A human hair keratin biomaterial hydrogel scaffold was evaluated as a nerve conduit luminal filler following median nerve transection injury in 10 Macaca fascicularis nonhuman primates (NHP). A 1 cm nerve gap was grafted with a NeuraGen® collagen conduit filled with either saline or keratin hydrogel and nerve regeneration was evaluated by electrophysiology for a period of 12 months. The keratin hydrogel-grafted nerves showed significant improvement in return of compound motor action potential (CMAP) latency and recovery of baseline nerve conduction velocity (NCV) compared with the saline-treated nerves. Histological evaluation was performed on retrieved median nerves and abductor pollicis brevis (APB) muscles at 12 months. Nerve histomorphometry showed a significantly larger nerve area in the keratin group compared with the saline group and the keratin APB muscles had a significantly higher myofiber density than the saline group. This is the first published study to show that an acellular biomaterial hydrogel conduit filler can be used to enhance peripheral nerve regeneration and motor recovery in an NHP model.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Action Potentials / drug effects
  • Animals
  • Antibodies / metabolism
  • Axons / drug effects
  • Axons / metabolism
  • Electrophysiological Phenomena / drug effects*
  • Female
  • Hair / chemistry*
  • Humans
  • Hydrogel, Polyethylene Glycol Dimethacrylate / pharmacology*
  • Keratins / pharmacology*
  • Macaca fascicularis / physiology*
  • Median Nerve / drug effects
  • Median Nerve / pathology
  • Median Nerve / physiopathology*
  • Motor Activity / drug effects
  • Muscles / drug effects
  • Muscles / pathology
  • Myelin Sheath / metabolism
  • Nerve Regeneration / drug effects*
  • Neural Conduction / drug effects
  • Tissue Scaffolds / chemistry*
  • Tolonium Chloride / metabolism


  • Antibodies
  • Tolonium Chloride
  • Hydrogel, Polyethylene Glycol Dimethacrylate
  • Keratins