State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Engineering Research Center of Oral Translational Medicine, Ministry of Education & National Engineering Laboratory for Oral Regenerative Medicine, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China; Department of Oral and Maxillofacial Surgery, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China.
State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Engineering Research Center of Oral Translational Medicine, Ministry of Education & National Engineering Laboratory for Oral Regenerative Medicine, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China.
Acta Biomater. 2022 May;144:242-257. doi: 10.1016/j.actbio.2022.03.045. Epub 2022 Mar 30.
Combined injectable cell-laden microspheres and angiogenesis approaches are promising for functional vascularized endodontic regeneration. However, advanced microsphere designs and production techniques that benefit practical applications are rarely developed. Herein, gelatin methacryloyl (GelMA)-alginate core-shell microcapsules were fabricated to co-encapsulate human dental pulp stem cells (hDPSCs) and human umbilical vein endothelial cells (HUVECs) based on a coaxial electrostatic microdroplet technique. This technique enables high-throughput production, convenient collection, and minimal material waste. The average diameter of core-shell microcapsules was ∼359 µm, and that of GelMA cores was ∼278 µm. There were higher proliferation rates for hDPSCs and HUVECs co-encapsulated in the GelMA cores than for hDPSCs or HUVECs monoculture group. HUVECs assembled to form 3D capillary-like networks in co-culture microcapsules. Moreover, HUVECs promoted the osteo/odontogenic differentiation of hDPSCs in microcapsules. After 14 days of cultivation, prevascularized microtissues formed in microcapsules that contained abundant deposited extracellular matrix (ECM); no microcapsule aggregation occurred. In vivo studies confirmed that better microvessel formation and pulp-like tissue regeneration occurred in the co-culture group than in hDPSCs group. Thus, an effective platform for prevascularization microtissue preparation was proposed and showed great promise in endodontic regeneration and tissue engineering applications. STATEMENT OF SIGNIFICANCE: Cell-laden microspheres combined with the proangiogenesis approach are promising in endodontic regeneration. We proposed GelMA-alginate core-shell microcapsules generated via the coaxial electrostatic microdroplet (CEM) method, which utilizes a double-lumen needle to allow for core-shell structures to form. The microcapsules were used for co-culturing hDPSCs and HUVECs to harvest large amounts of prevascularized microtissues, which further showed improved vascularization and pulp-like tissue regeneration in vivo. This CEM method and the microcapsule system have advantages of high-throughput generation, convenient collection, and avoid aggregation during long-term culturing. We proposed a high-effective platform for mass production of prevascularized microtissues, which exhibit great promise in the clinical transformation of endodontic regeneration and other applications in regenerative medicine.
将载细胞的可注射微球与血管生成方法相结合，有望实现功能性血管化牙髓再生。然而，很少有开发有利于实际应用的先进微球设计和生产技术。在此，基于同轴静电微滴技术，制备了明胶甲基丙烯酰（GelMA）-海藻酸盐核壳微胶囊，以共包封人牙髓干细胞（hDPSCs）和人脐静脉内皮细胞（HUVECs）。该技术可实现高通量生产、方便收集和最小的材料浪费。核壳微胶囊的平均直径约为 359μm，GelMA 核的平均直径约为 278μm。共包封在 GelMA 核中的 hDPSCs 和 HUVECs 的增殖率高于 hDPSCs 或 HUVECs 单培养组。HUVECs 在共培养微胶囊中组装形成 3D 毛细血管样网络。此外，HUVECs 促进了微胶囊中 hDPSCs 的成骨/成牙本质分化。培养 14 天后，在含有丰富细胞外基质（ECM）沉积的微胶囊中形成了预血管化的微组织；微胶囊没有聚集。体内研究证实，共培养组的微血管形成和牙髓样组织再生优于 hDPSCs 组。因此，提出了一种有效的预血管化微组织制备平台，在牙髓再生和组织工程应用中具有广阔的应用前景。
载细胞微球与促血管生成方法相结合有望应用于牙髓再生。我们提出了一种基于同轴静电微滴（CEM）方法的 GelMA-海藻酸盐核壳微胶囊，该方法使用双腔针形成核壳结构。微胶囊用于共培养 hDPSCs 和 HUVECs 以获得大量预血管化的微组织，进一步在体内显示出更好的血管化和牙髓样组织再生。该 CEM 方法和微胶囊系统具有高通量生成、方便收集和避免长期培养过程中聚集的优点。我们提出了一种高效的大规模生产预血管化微组织的平台，该平台在牙髓再生的临床转化和再生医学的其他应用中具有广阔的应用前景。
