The axonal regeneration across a honeycomb collagen sponge applied to the transected spinal cord.
We developed a honeycomb-shaped lyophilized Type I atelocollagen (Honeycomb Collagen: HC) with different pore sizes, and the effectiveness of the honeycomb shape on nerve regeneration was examined. We analyzed neurite outgrowth of dorsal root ganglion (DRG) explants on HC, both in vitro and, with direct implantation of HC into the defects of adult rat spinal cords, in vivo. The neurites of DRGs on HC extended linearly through the pores. HC with a 400 microm-pore size enhanced neurite extension, and YIGSR laminin peptide coating to the HC extended more neurites than fibronectin coating. The HC scaffolds coated with YIGSR were implanted into 2 mm-defects of spinal cords at the level of T8-9. Four weeks after implantation, the implants had degraded and been replaced with self-tissues, repairing the injured site. Neurofilament-positive fibers were observed in the implantation area and passed the borders between the HC and spinal cord stumps. Functionally, a motor-evoked potential was observed in the quadriceps femoris muscle 10 weeks after implantation. The electrophysiological examination showed reconstruction of axon tracts over the implant. This result indicates that our developed honeycomb shape is advantageous for host spinal cord compared to the random pored sponge shape, and that it promotes axonal regeneration after spinal cord injury.
Department of Orthopaedic and Spinal Surgery, Tokyo Medical and Dental University Graduate School, 1-5-45 Yushima Bunkyo-ku Tokyo, 113-8519 Japan.
Kazuyuki
K
Fukushima
Mitsuhiro
M
Enomoto
Shoji
S
Tomizawa
Makoto
M
Takahashi
Yoshiaki
Y
Wakabayashi
Soichiro
S
Itoh
Yoshinori
Y
Kuboki
Kenichi
K
Shinomiya
D000818:Animals; D001369:Axons / Q000502:physiology*; D020099:Coated Materials, Biocompatible; D003094:Collagen; D019054:Evoked Potentials, Motor; D016326:Extracellular Matrix Proteins / Q000502:physiology; D005260:Female; D005353:Fibronectins; D005727:Ganglia, Spinal / Q000293:injuries / Q000503:physiopathology*; D009416:Nerve Regeneration / Q000502:physiology*; D016501:Neurites / Q000502:physiology; D009842:Oligopeptides; D016062:Porosity; D051381:Rats; D017207:Rats, Sprague-Dawley; D013119:Spinal Cord Injuries / Q000503:physiopathology*; D054457:Tissue Scaffolds
D020099:Coated Materials, Biocompatible; D016326:Extracellular Matrix Proteins; D005353:Fibronectins; D009842:Oligopeptides; C059821:atelocollagen; C081571:tyrosyl-isoleucyl-glycyl-seryl-arginine; D003094:Collagen