title: Hydrogel-beta-TCP scaffolds and stem cells for tissue engineering bone.
abstract: Trabecular bone is a material of choice for reconstruction after trauma and tumor resection and for correction of congenital defects. Autologous bone grafts are available in limited shapes and sizes; significant donor site morbidity is another major disadvantage to this approach. To overcome these limitations, we used a tissue engineering approach to create bone replacements in vitro, combining bone-marrow-derived differentiated mesenchymal stem cells (MSCs) suspended in hydrogels and 3-dimensionally printed (3DP) porous scaffolds made of beta-tricalcium-phosphate (beta-TCP). The scaffolds provided support for the formation of bone tissue in collagen I, fibrin, alginate, and pluronic F127 hydrogels during culturing in oscillating and rotating dynamic conditions. Histological evaluation including toluidine blue, alkaline phosphatase, and von Kossa staining was done at 1, 2, 4, and 6 weeks. Radiographic evaluation and high-resolution volumetric CT (VCT) scanning, expression of bone-specific genes and biomechanical compression testing were performed at 6 weeks. Both culture conditions resulted in similar bone tissue formation. Histologically collagen I and fibrin hydrogels specimens had superior bone tissue, although radiopacities were detected only in collagen I samples. VCT scan revealed density values in all but the Pluronic F127 samples, with Houndsfield unit values comparable to native bone in collagen I and fibrin glue samples. Expression of bone-specific genes was significantly higher in the collagen I samples. Pluronic F127 hydrogel did not support formation of bone tissue. All samples cultured in dynamic oscillating conditions had slightly higher mechanical strength than under rotating conditions. Bone tissue can be successfully formed in vitro using constructs comprised of collagen I hydrogel, MSCs, and porous beta-TCP scaffolds.
authors.affiliation: Laboratory for Tissue Engineering and Organ Fabrication, Warren 11-1157, Massachusetts General Hospital, Harvard, Medical School, 55 Fruit Street, Boston, MA 02114, USA.
authors.forename: Christian
authors.initials: C
authors.lastname: Weinand
authors.forename: Irina
authors.initials: I
authors.lastname: Pomerantseva
authors.forename: Craig M
authors.initials: CM
authors.lastname: Neville
authors.forename: Rajiv
authors.initials: R
authors.lastname: Gupta
authors.forename: Eli
authors.initials: E
authors.lastname: Weinberg
authors.forename: Ijad
authors.initials: I
authors.lastname: Madisch
authors.forename: Frederic
authors.initials: F
authors.lastname: Shapiro
authors.forename: Harutsugi
authors.initials: H
authors.lastname: Abukawa
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Troulis
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Vacanti
mesh_terms: D000464:Alginates; D000818:Animals; D001483:Base Sequence; D001696:Biomechanical Phenomena; D001842:Bone and Bones; D002130:Calcium Phosphates; D024042:Collagen Type I; D017931:DNA Primers; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D020100:Hydrogels; D059630:Mesenchymal Stem Cells / Q000166:cytology; D020442:Poloxamer; D013552:Swine; D013556:Swine, Miniature; D023822:Tissue Engineering; D014158:Transcription, Genetic
chemical_list: D000464:Alginates; D002130:Calcium Phosphates; D024042:Collagen Type I; D017931:DNA Primers; D006603:Hexuronic Acids; D020100:Hydrogels; C485817:beta-tricalcium phosphate; D020442:Poloxamer; D020723:Glucuronic Acid