Ectopic osteogenesis of tissue-engineered bone using allogenic bone marrow mesenchymal stem cells in beagle dogs
Wu Jing-guo
Ma Yan
Cao Fei-fei
Wang De-feng
Zang Qing-fu
Zhang Xi-shan
Li Yong
Abstract：BACKGROUND:Al ogenic bone marrow mesenchymal stem cel s as seed cel s for tissue engineering have become the future trend of development. OBJECTIVE:To investigate the osteogenic effects of al ogenic bone marrow mesenchymal stem cel s and the outcome in vivo. METHODS:Bone marrow mesenchymal stem cel s from beagle dogs were marked with chloromethylbenzoyl ammonia fluorescent dye (CM-Dil), and the proliferation of labeled cel s was measured using MTT assay in vitro. Autologous or al ogenic bone marrow mesenchymal stem cel s were inoculated into coral andβ-tricalcium phosphate scaffolds for 7 days osteogenic induction and then subcutaneously implanted into the back of beagle dogs. Dogs undergoing blank scaffold implantation served as negative controls. Hematoxylin-eosin staining was used to observe new bone formation at 3 days, 1, 2, 4, 8, 12 weeks after surgery. Bone formation area was statistical y analyzed using ipp software. In the CM-Dil group, frozen sections were made to trace the in vivo outcome of bone marrow mesenchymal stem cel s under a fluorescence microscope. RESULTS AND CONCLUSION:The osteogenesis speed in the al ogenic bone tissue engineering group was faster than that in the autologous bone tissue engineering group at 4-8 weeks after implantation, but no significant difference between the two groups was found beginning at the 12th week. At 4 weeks after implantation, the expression ofγ-carboxy glutamic acid protein in the autologous bone tissue engineering group was higher than that in the al ogenic bone tissue engineering group, prompting the bone mineralization appeared earlier in the latter group than the former one. ELISA results showed that the expression of alkaline phosphatase and osteocalcin in the autologous bone tissue engineering group was higher than that in the al ogenic bone tissue engineering group at 4 weeks after implantation, and then the expression showed no difference at 12 weeks. CM-Dil labeling results showed that the number of al ogenic bone marrow mesenchymal stem cel s was reduced significantly compared with that of autologous bone marrow mesenchymal stem cel s. Al these findings indicate that the ectopic osteogenesis of the al ogenic tissue-engineered bone in large animals is found within 12 weeks after implantation, but the osteogenesis efficiency at early stage (within 8 weeks) is lower compared with the autologous tissue-engineered bone. This difference may be related to the post-implantation immunoreactions that lead to the reduction in cel number.
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Publication Date：2016-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 6845-6853 )