University Center of Orthopaedic, Trauma and Plastic Surgery and Center for Translational Bone, Joint and Soft Tissue Research, University Hospital Carl Gustav Carus at Technische Universität Dresden, 01307 Dresden, Germany.
Department of Orthopaedic Surgery and Bioengineering, Stanford University, 94305 Stanford, USA.
Curr Stem Cell Res Ther. 2022;17(5):480-491. doi: 10.2174/1574888X17666220215100732.
While bone marrow-derived mesenchymal stromal cells (BM-MSCs) have been used for many years in bone tissue engineering applications, the procedure still has drawbacks such as painful collection methods and damage to the donor site. Dental pulp-derived stem cells (DPSCs) are readily accessible, occur in high amounts, and show a high proliferation and differentiation capability. Therefore, DPSCs may be a promising alternative for BM-MSCs to repair bone defects.
The aim of this study was to investigate the bone regenerative potential of DPSCs in comparison to BM-MSCs in vitro and in vivo.
In vitro investigations included analysis of cell doubling time as well as proliferation and osteogenic differentiation. For the in vivo study, 36 male NMRI nude mice were randomized into 3 groups: 1) control (cell-free mineralized collagen matrix (MCM) scaffold), 2) MCM + DPSCs, and 3) MCM + BMMSCs. Critical size 2 mm bone defects were created at the right femur of each mouse and stabilized by an external fixator. After 6 weeks, animals were euthanized, and microcomputed tomography scans (μCT) and histological analyses were performed.
In vitro DPSCs showed a 2-fold lower population doubling time and a 9-fold higher increase in proliferation when seeded onto MCM scaffolds as compared to BM-MSCs, but DPSCs showed a significantly lower osteogenic capability than BM-MSCs. In vivo, the healing of the critical bone defect in NMRI nude mice was comparable among all groups.
Pre-seeding of MCM scaffolds with DPSCs and BM-MSCs did not enhance bone defect healing.
虽然骨髓间充质基质细胞（BM-MSCs）在骨组织工程应用中已经使用了多年，但该过程仍存在一些缺点，如采集方法疼痛和供体部位损伤。牙髓干细胞（DPSCs）易于获取，数量多，增殖和分化能力高。因此，DPSCs 可能是修复骨缺损的 BM-MSCs 的一种有前途的替代物。
本研究旨在比较 DPSCs 和 BM-MSCs 在体外和体内的骨再生潜力。
体外研究包括分析细胞倍增时间以及增殖和成骨分化。对于体内研究，将 36 只雄性 NMRI 裸鼠随机分为 3 组：1）对照组（无细胞矿化胶原基质（MCM）支架）、2）MCM+DPSCs 和 3）MCM+BM-MSCs。在每只小鼠的右侧股骨上创建 2mm 大小的临界骨缺损，并通过外固定器稳定。6 周后，处死动物，并进行 microCT 扫描（μCT）和组织学分析。
与 BM-MSCs 相比，DPSCs 在接种到 MCM 支架上时，倍增时间缩短了 2 倍，增殖增加了 9 倍，但 DPSCs 的成骨能力明显低于 BM-MSCs。在体内，NMRI 裸鼠的临界骨缺损愈合在所有组之间相当。
在 MCM 支架上预接种 DPSCs 和 BM-MSCs 并没有增强骨缺损的愈合。
