title: Intervertebral Disc Tissue Engineering with Natural Extracellular Matrix-Derived Biphasic Composite Scaffolds.
abstract: Tissue engineering has provided an alternative therapeutic possibility for degenerative disc diseases. However, we lack an ideal scaffold for IVD tissue engineering. The goal of this study is to fabricate a novel biomimetic biphasic scaffold for IVD tissue engineering and evaluate the feasibility of developing tissue-engineered IVD in vitro and in vivo. In present study we developed a novel integrated biphasic IVD scaffold using a simple freeze-drying and cross-linking technique of pig bone matrix gelatin (BMG) for the outer annulus fibrosus (AF) phase and pig acellular cartilage ECM (ACECM) for the inner nucleus pulposus (NP) phase. Histology and SEM results indicated no residual cells remaining in the scaffold that featured an interconnected porous microstructure (pore size of AF and NP phase 401.4 ± 13.1 μm and 231.6 ± 57.2 μm, respectively). PKH26-labeled AF and NP cells were seeded into the scaffold and cultured in vitro. SEM confirmed that seeded cells could anchor onto the scaffold. Live/dead staining showed that live cells (green fluorescence) were distributed in the scaffold, with no dead cells (red fluorescence) being found. The cell-scaffold constructs were implanted subcutaneously into nude mice and cultured for 6 weeks in vivo. IVD-like tissue formed in nude mice as confirmed by histology. Cells in hybrid constructs originated from PKH26-labeled cells, as confirmed by in vivo fluorescence imaging system. In conclusion, the study demonstrates the feasibility of developing a tissue-engineered IVD in vivo with a BMG- and ACECM-derived integrated AF-NP biphasic scaffold. As well, PKH26 fluorescent labeling with in vivo fluorescent imaging can be used to track cells and analyse cell--scaffold constructs in vivo.
authors.affiliation: Department of minimally invasive spine surgery, Tianjin Hospital, 406 Jie Fang Nan Road, Hexi District, Tianjin, 300211, People's Republic of China.
authors.forename: Baoshan
authors.initials: B
authors.lastname: Xu
authors.affiliation: Department of minimally invasive spine surgery, Tianjin Hospital, 406 Jie Fang Nan Road, Hexi District, Tianjin, 300211, People's Republic of China; Tianjin medical university, Tianjin, 300070, People's Republic of China.
authors.forename: Haiwei
authors.initials: H
authors.lastname: Xu
authors.affiliation: Department of minimally invasive spine surgery, Tianjin Hospital, 406 Jie Fang Nan Road, Hexi District, Tianjin, 300211, People's Republic of China; Tianjin medical university, Tianjin, 300070, People's Republic of China.
authors.forename: Yaohong
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Cell Engineering Laboratory of Orthopaedic Institute, Tianjin Hospital, Tianjin, 300211, People's Republic of China.
authors.forename: Xiulan
authors.initials: X
authors.lastname: Li
authors.affiliation: Cell Engineering Laboratory of Orthopaedic Institute, Tianjin Hospital, Tianjin, 300211, People's Republic of China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of minimally invasive spine surgery, Tianjin Hospital, 406 Jie Fang Nan Road, Hexi District, Tianjin, 300211, People's Republic of China.
authors.forename: Xinlong
authors.initials: X
authors.lastname: Ma
authors.affiliation: Department of minimally invasive spine surgery, Tianjin Hospital, 406 Jie Fang Nan Road, Hexi District, Tianjin, 300211, People's Republic of China; Tianjin medical university, Tianjin, 300070, People's Republic of China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Yang
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D001842:Bone and Bones / Q000378:metabolism; D002356:Cartilage / Q000378:metabolism; D003432:Cross-Linking Reagents / Q000737:chemistry; D005109:Extracellular Matrix / Q000737:chemistry*; D005260:Female; D005456:Fluorescent Dyes / Q000737:chemistry; D005780:Gelatin / Q000737:chemistry; D007403:Intervertebral Disc / Q000473:pathology*; D055959:Intervertebral Disc Degeneration / Q000473:pathology; D008297:Male; D051379:Mice; D008819:Mice, Nude; D008855:Microscopy, Electron, Scanning; D009930:Organic Chemicals / Q000737:chemistry; D013552:Swine; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D003432:Cross-Linking Reagents; D005456:Fluorescent Dyes; D009930:Organic Chemicals; C070080:PKH 26; D005780:Gelatin