title: Tissue engineered regeneration of completely transected spinal cord using human mesenchymal stem cells.
abstract: The present study employed a combinatorial strategy using poly(D,L-lactide-co-glycolide) (PLGA) scaffolds seeded with human mesenchymal stem cells (hMSCs) to promote cell survival, differentiation, and neurological function in a completely transected spinal cord injury (SCI) model. The SCI model was prepared by complete removal of a 2-mm length of spinal cord in the eighth-to-ninth spinal vertebra, a procedure that resulted in bilateral hindlimb paralysis. PLGA scaffolds 2 mm in length without hMSCs (control) or with different numbers of hMSCs (1 × 10(5), 2 × 10(4), and 4 × 10(3)) were fitted into the completely transected spinal cord. Rats implanted with hMSCs received Basso-Beattie-Bresnahan scores for hindlimb locomotion of about 5, compared with ~2 for animals in the control group. The amplitude of motor-evoked potentials (MEPs) averaged 200-300 μV in all hMSC-implanted SCR model rats. In contrast, the amplitude of MEPs in control group animals averaged 135 μV at 4 weeks and then declined to 100 μV at 8 weeks. These results demonstrate functional recovery in a completely transected SCI model under conditions that exclude self-recovery. hMSCs were detected at the implanted site 4 and 8 weeks after transplantation, indicating in vivo survival of implanted hMSCs. Immunohistochemical staining revealed differentiation of implanted hMSCs into nerve cells, and immunostained images showed clear evidence for axonal regeneration only in hMSC-seeded PLGA scaffolds. Collectively, our results indicate that hMSC-seeded PLGA scaffolds induced nerve regeneration in a completely transected SCI model, a finding that should have significant implications for the feasibility of therapeutic and clinical hMSC-delivery using three-dimensional scaffolds, especially in the context of complete spinal cord transection.
authors.affiliation: Department of Molecular Science and Technology, Ajou University, Suwon 443-749, Republic of Korea.
authors.forename: Kkot Nim
authors.initials: KN
authors.lastname: Kang
authors.forename: Da Yeon
authors.initials: DY
authors.lastname: Kim
authors.forename: So Mi
authors.initials: SM
authors.lastname: Yoon
authors.forename: Ju Young
authors.initials: JY
authors.lastname: Lee
authors.forename: Bit Na
authors.initials: BN
authors.lastname: Lee
authors.forename: Jin Seon
authors.initials: JS
authors.lastname: Kwon
authors.forename: Hyo Won
authors.initials: HW
authors.lastname: Seo
authors.forename: Il Woo
authors.initials: IW
authors.lastname: Lee
authors.forename: Ha Cheol
authors.initials: HC
authors.lastname: Shin
authors.forename: Young Man
authors.initials: YM
authors.lastname: Kim
authors.forename: Hyun Soo
authors.initials: HS
authors.lastname: Kim
authors.forename: Jae Ho
authors.initials: JH
authors.lastname: Kim
authors.forename: Byoung Hyun
authors.initials: BH
authors.lastname: Min
authors.forename: Hai Bang
authors.initials: HB
authors.lastname: Lee
authors.forename: Moon Suk
authors.initials: MS
authors.lastname: Kim
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D004594:Electrophysiology; D005260:Female; D006801:Humans; D019344:Lactic Acid / Q000737:chemistry; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D011100:Polyglycolic Acid / Q000737:chemistry; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011916:Rats, Inbred F344; D013119:Spinal Cord Injuries / Q000628:therapy*; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid