Controlled release of neurotrophin-3 from fibrin-based tissue engineering scaffolds enhances neural fiber sprouting following subacute spinal cord injury.
This study investigated whether delayed treatment of spinal cord injury with controlled release of neurotrophin-3 (NT-3) from fibrin scaffolds can stimulate enhanced neural fiber sprouting. Long Evans rats received a T9 dorsal hemisection spinal cord injury. Two weeks later, the injury site was re-exposed, and either a fibrin scaffold alone, a fibrin scaffold containing a heparin-based delivery system with different concentrations of NT-3 (500 and 1,000 ng/mL), or a fibrin scaffold containing 1,000 ng/mL of NT-3 (no delivery system) was implanted into the injury site. The injured spinal cords were evaluated for morphological differences using markers for neurons, astrocytes, and chondroitin sulfate proteoglycans 2 weeks after treatment. The addition of 500 ng/mL of NT-3 with the delivery system resulted in an increase in neural fiber density compared to fibrin alone. These results demonstrate that the controlled release of NT-3 from fibrin scaffolds can enhance neural fiber sprouting even when treatment is delayed 2 weeks following injury.
Johnson
Philip J
PJ
Department of Biomedical Engineering, Washington University, St. Louis, Missouri 63130, USA.
Parker
Stanley R
SR
Sakiyama-Elbert
Shelly E
SE
D000818:Animals; D005260:Female; D005337:Fibrin; D009412:Nerve Fibers / Q000187:drug effects*; D009416:Nerve Regeneration; D020933:Neurotrophin 3 / Q000493:pharmacokinetics*; D051381:Rats; D020318:Rats, Long-Evans; D013116:Spinal Cord / Q000473:pathology; D013119:Spinal Cord Injuries / Q000628:therapy*; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry*
D020933:Neurotrophin 3; D005337:Fibrin