Department of Ophthalmology, Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, P. R. China.
Invest Ophthalmol Vis Sci. 2011 Mar 25;52(3):1735-41. doi: 10.1167/iovs.10-5988.
To repair the segmental orbital rim defects of dogs with three-dimensional (3D) tissue-engineered constructs derived from culturing autogenous bone marrow stromal cells (BMSCs) on β-tricalcium phosphate (β-TCP) scaffolds.
A 25-mm segmental defect on the canine inferior orbital rim was created. BMSCs were isolated and osteogenically induced in vitro, then were seeded onto 3D β-TCP scaffolds and implanted to repair the orbital defects after 5 days of cultivation. The group of noninduced BMSC/β-TCP, β-TCP alone, and the normal inferior orbital rim were set as controls. The orbits of all groups had spiral computed tomography (CT) scans 1, 4, 8, and 12 weeks after surgery. Gross examination, bone density, microCT, and histologic measurements were performed 12 weeks after surgery. The results were analyzed to evaluate the extent of bone repair.
Twelve weeks after surgery, CT examination revealed good inferior orbital rim recovery in the induced BMSC/β-TCP group, and the bone density was 0.30 ± 0.03 g/cm(2) with no dominant variance, compared with the normal control (P > 0.05). MicroCT and histologic examination confirmed that the implantations led to good repair of the defects. Pore-like spongy bone surrounded the implants through the section plane, with some residue remaining in the center. In contrast, the noninduced BMSC/β-TCP implants were not fully repaired, and nonunion was evident. The bony density for this group was 0.23 ± 0.07 g/cm(2), which was significantly lower than that of the control group (P < 0.05). The β-TCP group was largely held by fibrous tissues.
Engineered bone from induced BMSCs and 3D biodegradable β-TCP can efficiently repair critical-sized segmental orbital defects in dogs.
用培养自体骨髓基质细胞（BMSCs）于β-磷酸三钙（β-TCP）支架上所形成的三维（3D）组织工程构建物来修复犬的节段性眶缘缺损。
在犬的下眶缘创建一个 25mm 的节段性缺损。BMSCs 被分离出来并在体外成骨诱导，然后接种到 3D β-TCP 支架上，并在培养 5 天后植入以修复眶缺损。未诱导的 BMSC/β-TCP 组、单纯β-TCP 组和正常下眶缘组被设为对照组。所有组别的眼眶在手术后 1、4、8 和 12 周时均行螺旋 CT（CT）扫描。手术后 12 周时进行大体检查、骨密度、微 CT 和组织学测量。分析结果以评估骨修复的程度。
手术后 12 周时，CT 检查显示诱导的 BMSC/β-TCP 组下眶缘恢复良好，其骨密度为 0.30±0.03g/cm²，无明显差异，与正常对照组相比（P＞0.05）。微 CT 和组织学检查证实植入物导致了良好的缺损修复。多孔海绵状骨沿植入物的剖面环绕，中心仍有一些残留。相比之下，未诱导的 BMSC/β-TCP 植入物未完全修复，且有明显的骨不连。该组的骨密度为 0.23±0.07g/cm²，明显低于对照组（P＜0.05）。β-TCP 组主要被纤维组织所占据。
诱导的 BMSCs 和 3D 可生物降解的β-TCP 所形成的工程化骨可以有效地修复犬的临界尺寸节段性眶缘缺损。
