title: Bone marrow stromal cell sheets may promote axonal regeneration and functional recovery with suppression of glial scar formation after spinal cord transection injury in rats.
abstract: OBJECTIVE Transplantation of bone marrow stromal cells (BMSCs) is a theoretical potential as a therapeutic strategy in the treatment of spinal cord injury (SCI). Although a scaffold is sometimes used for retaining transplanted cells in damaged tissue, it is also known to induce redundant immunoreactions during the degradation processes. In this study, the authors prepared cell sheets made of BMSCs, which are transplantable without a scaffold, and investigated their effects on axonal regeneration, glial scar formation, and functional recovery in a completely transected SCI model in rats. METHODS BMSC sheets were prepared from the bone marrow of female Fischer 344 rats using ascorbic acid and were cryopreserved until the day of transplantation. A gelatin sponge (GS), as a control, or BMSC sheet was transplanted into a 2-mm-sized defect of the spinal cord at the T-8 level. Axonal regeneration and glial scar formation were assessed 2 and 8 weeks after transplantation by immunohistochemical analyses using anti-Tuj1 and glial fibrillary acidic protein (GFAP) antibodies, respectively. Locomotor function was evaluated using the Basso, Beattie, and Bresnahan scale. RESULTS The BMSC sheets promoted axonal regeneration at 2 weeks after transplantation, but there was no significant difference in the number of Tuj1-positive axons between the sheet- and GS-transplanted groups. At 8 weeks after transplantation, Tuj1-positive axons elongated across the sheet, and their numbers were significantly greater in the sheet group than in the GS group. The areas of GFAP-positive glial scars in the sheet group were significantly reduced compared with those of the GS group at both time points. Finally, hindlimb locomotor function was ameliorated in the sheet group at 4 and 8 weeks after transplantation. CONCLUSIONS The results of the present study indicate that an ascorbic acid-induced BMSC sheet is effective in the treatment of SCI and enables autologous transplantation without requiring a scaffold.
authors.affiliation: Department of Orthopaedic Surgery, Nara Medical University, Kashihara.|Department of Anatomy and Cell Biology, Faculty of Medicine, Nara Medical University, Kashihara.
authors.forename: Akinori
authors.initials: A
authors.lastname: Okuda
authors.affiliation: Department of Anatomy and Cell Biology, Faculty of Medicine, Nara Medical University, Kashihara.
authors.forename: Noriko
authors.initials: N
authors.lastname: Horii-Hayashi
authors.affiliation: Department of Anatomy and Cell Biology, Faculty of Medicine, Nara Medical University, Kashihara.
authors.forename: Takayo
authors.initials: T
authors.lastname: Sasagawa
authors.affiliation: Department of Orthopaedic Surgery, Nara Medical University, Kashihara.
authors.forename: Takamasa
authors.initials: T
authors.lastname: Shimizu
authors.affiliation: Department of Orthopaedic Surgery, Nara Medical University, Kashihara.
authors.forename: Hideki
authors.initials: H
authors.lastname: Shigematsu
authors.affiliation: Department of Orthopaedic Surgery, Nara Medical University, Kashihara.
authors.forename: Eiichiro
authors.initials: E
authors.lastname: Iwata
authors.affiliation: Department of Orthopaedic Surgery, Nara Medical University, Kashihara.
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Morimoto
authors.affiliation: Department of Orthopaedic Surgery, Nara Medical University, Kashihara.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Masuda
authors.affiliation: Spine and Spinal Cord Surgery Center, Nara Prefecture General Medical Center; and.
authors.forename: Munehisa
authors.initials: M
authors.lastname: Koizumi
authors.affiliation: Department of Public Health, Health Management, and Policy, Nara Medical University, Kashihara, Nara, Japan.
authors.forename: Manabu
authors.initials: M
authors.lastname: Akahane
authors.affiliation: Department of Anatomy and Cell Biology, Faculty of Medicine, Nara Medical University, Kashihara.
authors.forename: Mayumi
authors.initials: M
authors.lastname: Nishi
authors.affiliation: Department of Orthopaedic Surgery, Nara Medical University, Kashihara.
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Tanaka
mesh_terms: D000818:Animals; D001369:Axons / Q000473:pathology; D016026:Bone Marrow Transplantation / Q000379:methods; D002454:Cell Differentiation / Q000502:physiology; D004195:Disease Models, Animal; D005260:Female; D045164:Mesenchymal Stem Cell Transplantation / Q000379:methods; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D009416:Nerve Regeneration / Q000187:drug effects*; D009457:Neuroglia / Q000473:pathology; D011916:Rats, Inbred F344; D020127:Recovery of Function / Q000187:drug effects*; D013116:Spinal Cord / Q000473:pathology; D013119:Spinal Cord Injuries / Q000503:physiopathology / Q000628:therapy*
keywords: AscP = l-ascorbic acid phosphate; BBB = Basso, Beattie, and Bresnahan; BMSC = bone marrow stromal cell; DAPI = 4′,6-diamidino-2-phenylindole; ECM = extracellular matrix; GFAP = glial fibrillary acidic protein; GS = gelatin sponge; PBS = phosphate-buffered saline; PBST = PBS with Triton X-100; SCI = spinal cord injury; ascorbic acid; axonal regeneration; bone marrow stromal cell; cell sheet; glial scar; spinal cord injury