Carmon Idan, Kalmus Shira, Zobrab Anna, Alterman Michael, Emram Raphaelle, Gussarsky May, Kandel Leonid, Reich Eli, Casap Nardi, Dvir-Ginzberg Mona
Laboratory of Cartilage Biology, Institute of Bio-Medical and Oral Research, Faculty of Dental Medicine, Hebrew University of Jerusalem, Jerusalem, Israel.
Deptatement. of Maxillofacial Surgery, Faculty of Dental Medicine, Hadassah-Hebrew University, Jerusalem, Israel.
J Tissue Eng. 2023 Mar 18;14:20417314231159740. doi: 10.1177/20417314231159740. eCollection 2023 Jan-Dec.
In cranial flat bone fractures, spontaneous bone repair will occur only when the fracture ends are in close contact. However, in cases wherein bone discontinuity is extensive, surgical interventions are often required. To this end, autologous bone is harvested and surgically integrated into the site of fracture. Here we propose to use cartilage, as an alternative autologous source, to promote cranial fracture repair. The advantage of this approach is the potential reduction in donor site morbidity, likely due to the avascular and aneural nature of cartilage. As a first step we attempted to induce cartilage mineralization in vitro, using micromass primary chondrocyte cultures, incubated with BMP2 and/or WISP1, which were examined histologically following a 3-week culture period. Next, chondrocyte seeded collagen scaffolds were evaluated in vitro for expression profiles and ALP activity. Finally, chondrocyte-seeded collagen scaffolds were implanted in a Lewis rats 8 mm critical calvaria defect model, which was imaged via live CT for 12 weeks until sacrifice. End points were analyzed for microCT, histology, and serum levels of bone related markers. Micromass cultures exhibited an osseous inducing trend following WISP1 administration, which was maintained in chondrocyte seeded scaffolds. Accordingly, in vivo analysis was carried out to assess the impact of WISP1-pretreated chondrocytes (WCS) versus untreated chondrocytes (UCS) in calvaria defect model and compared to untreated control comprised of a defect-associated blood clot (BC) or empty collagen scaffold (CS) implant. Live CT and microCT exhibited higher mineralization volumes in critical defect implanted with UCS, with some structural improvements in WCS. Histological analysis exhibited higher anabolic bone formation in WCS and trabecular bone was detected in WCS and UCS groups. Chondrocytes implanted into critical cranial defect expedite the formation of native-like osseous tissue, especially after WISP1 priming in culture. Ultimately, these data support the use of autologous chondrocytes to repair critical maxillofacial defects.
在颅骨扁平骨骨折中，只有当骨折端紧密接触时才会发生自发性骨修复。然而，在骨连续性广泛中断的情况下，通常需要手术干预。为此，采集自体骨并通过手术将其整合到骨折部位。在此，我们提议使用软骨作为替代自体来源，以促进颅骨骨折修复。这种方法的优点是可能降低供体部位的发病率，这可能是由于软骨无血管和无神经的特性。作为第一步，我们尝试在体外诱导软骨矿化，使用微团原代软骨细胞培养物，与BMP2和/或WISP1一起孵育，在培养3周后进行组织学检查。接下来，对接种软骨细胞的胶原支架进行体外表达谱和碱性磷酸酶活性评估。最后，将接种软骨细胞的胶原支架植入Lewis大鼠8毫米关键颅骨缺损模型中，通过实时CT成像12周，直至处死。对终点进行了显微CT、组织学和骨相关标志物血清水平分析。微团培养物在给予WISP1后呈现出成骨诱导趋势，并在接种软骨细胞的支架中得以维持。因此，在体内分析中，评估了WISP1预处理的软骨细胞（WCS）与未处理的软骨细胞（UCS）在颅骨缺损模型中的影响，并与由缺损相关血凝块（BC）或空胶原支架（CS）植入物组成的未处理对照组进行比较。实时CT和显微CT显示，植入UCS的关键缺损处矿化体积更高，WCS有一些结构改善。组织学分析显示，WCS中有更高的合成代谢性骨形成，并且在WCS和UCS组中检测到了小梁骨。植入关键颅骨缺损的软骨细胞加速了类天然骨组织的形成，尤其是在培养中用WISP1预处理后。最终，这些数据支持使用自体软骨细胞修复关键的颌面缺损。
