State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan 610041, China; Biomaterials & Tissue Engineering Division, Department of Endodontics, Prosthodontics and Operative Dentistry, University of Maryland Dental School, Baltimore, MD 21201, USA.
Biomaterials. 2013 Dec;34(38):9917-25. doi: 10.1016/j.biomaterials.2013.09.002. Epub 2013 Sep 18.
Human umbilical cord mesenchymal stem cells (hUCMSCs) are inexhaustible and can be harvested at a low cost without an invasive procedure. However, there has been no report on comparing hUCMSCs with human bone marrow MSCs (hBMSCs) for bone regeneration in vivo. The aim of this study was to investigate hUCMSC and hBMSC seeding on macroporous calcium phosphate cement (CPC), and to compare their bone regeneration in critical-sized cranial defects in rats. Cell attachment, osteogenic differentiation and mineral synthesis on RGD-modified macroporous CPC were investigated in vitro. Scaffolds with cells were implanted in 8-mm defects of athymic rats. Bone regeneration was investigated via micro-CT and histological analysis at 4, 12, and 24 weeks. Three groups were tested: CPC with hUCMSCs, CPC with hBMSCs, and CPC control without cells. Percentage of live cells and cell density on CPC in vitro were similarly good for hUCMSCs and hBMSCs. Both cells had high osteogenic expressions of alkaline phosphatase, osteocalcin, collagen I, and Runx2. Bone mineral density and trabecular thickness in hUCMSC and hBMSC groups in vivo were greater than those of CPC control group. New bone amount for hUCMSC-CPC and hBMSC-CPC constructs was increased by 57% and 88%, respectively, while blood vessel density was increased by 15% and 20%, than CPC control group at 24 weeks. hUCMSC-CPC and hBMSC-CPC groups generally had statistically similar bone mineral density, new bone amount and vessel density. In conclusion, hUCMSCs seeded on CPC were shown to match the bone regeneration efficacy of hBMSCs in vivo for the first time. Both hUCMSC-CPC and hBMSC-CPC constructs generated much more new bone and blood vessels than CPC without cells. Macroporous RGD-grafted CPC with stem cell seeding is promising for craniofacial and orthopedic repairs.
人脐带间充质干细胞（hUCMSCs）是取之不尽的，可以以非侵入性的方式低成本地收获，而无需进行侵入性手术。然而，目前还没有关于 hUCMSCs 与人类骨髓间充质干细胞（hBMSCs）在体内骨再生方面的比较报告。本研究旨在研究 hUCMSC 和 hBMSC 在大孔磷酸钙水泥（CPC）上的接种情况，并比较它们在大鼠临界尺寸颅骨缺损中的骨再生情况。在体外研究了 RGD 修饰的大孔 CPC 上的细胞附着、成骨分化和矿物合成。将带有细胞的支架植入无胸腺大鼠的 8mm 缺损中。通过 micro-CT 和组织学分析在 4、12 和 24 周时研究骨再生情况。测试了三组：CPC 加 hUCMSCs、CPC 加 hBMSCs 和 CPC 对照组（无细胞）。体外 hUCMSCs 和 hBMSCs 的活细胞百分比和细胞密度相似。两种细胞的碱性磷酸酶、骨钙素、I 型胶原和 Runx2 的成骨表达均较高。体内 hUCMSC 和 hBMSC 组的骨矿物质密度和小梁厚度均大于 CPC 对照组。hUCMSC-CPC 和 hBMSC-CPC 构建体的新骨量分别增加了 57%和 88%，而血管密度分别增加了 15%和 20%，与 CPC 对照组相比，在 24 周时。hUCMSC-CPC 和 hBMSC-CPC 组的骨矿物质密度、新骨量和血管密度总体上具有统计学相似性。总之，首次证明 hUCMSCs 接种在 CPC 上与体内 hBMSCs 的骨再生效果相当。与无细胞的 CPC 相比，hUCMSC-CPC 和 hBMSC-CPC 构建体产生了更多的新骨和血管。大孔 RGD 接枝 CPC 与干细胞接种具有促进颅面和骨科修复的潜力。
