基于iPSC-MSCs细胞的3D打印生物材料构建及牙周再生效果评价

Periodontal regeneration is extremely challenging due to the complexity of structure and function of periodontal supporting tissues. Stem cell-based tissue engineering technologies hold great potential in achieving periodontal regeneration. Induced pluripotent stem cells-derived mesenchymal stem cells (iPSC-MSCs) have multi-lineage differential potential and high proliferation capacity, and they have been recognized as a promising source for patient-specific stem cells. 3D printing technology provides a new approach for multiple tissue regeneration. It enables fabrication of defect-matched tissue engineering scaffolds with precise microstructures. Combination of both iPSC-MSCs and 3D printing is favorable for achieving personalized and accurate periodontal regeneration. Through utilization of clinically easily accessible gingival tissues, we have recently successfully established iPSCs from human gingival fibroblasts. In this study, iPSCs will be induced into iPSC-MSCs. Based on 3D scanning data of periodontal defect, a rhGDF-5-delivary multiphasic scaffold will be fabricated via 3D printing of materials with excellent biological properties including hyaluronic acid hydrogel, beta-tricalcium phosphate and polycaprolactone. By mimicking the “bone-periodontal ligament-cementum” interfaces of periodontal supporting tissue, the 3D scaffold is characterized by a multiphasic structure of “mineralized tissue-fibrous tissue-mineralized tissue”. It will be used as a carrier of iPSC-MSCs to regenerate the alveolar bone, periodontal ligament and cementum. The effects of this iPSC-MSCs-based 3D printing biological material on regeneration of periodontal tissues are evaluated in a periodontal defect model in rats. This study will provide a novel strategy for periodontal regeneration.

由于牙周支持组织结构和功能的复杂性，牙周再生治疗极具挑战性，以干细胞为基础的组织再生技术有望实现牙周再生。诱导多能干细胞来源的间充质干细胞（iPSC-MSCs）是很有前景的患者特异性干细胞来源。3D打印技术能够制备具有精确显微结构的组织工程支架，为多组织再生提供了新的途径。两者的结合有助于实现牙周再生的个性化和精准治疗。我们前期建立了人牙龈成纤维细胞来源的iPSCs，本研究拟将其诱导为iPSC-MSCs；根据牙周缺损三维数据，选择生物学性能优良的透明质酸水凝胶、β-磷酸三钙和聚己内酯，利用3D打印技术制备rhGDF-5 缓释“矿化组织-纤维组织-矿化组织”多相支架，模拟牙周支持组织“骨-牙周膜-牙骨质”界面，并作为iPSC-MSCs的载体以修复牙周组织。通过植入大鼠牙周损模型，评价这一基于iPSC-MSCs的3D打印生物材料在体内再生牙周组织的效果，为牙周再生提供新的策略。

牙周病是一类发病率高，且对牙周支持组织和全身健康造成威胁的炎症性疾病。传统意义上的牙周治疗难以使牙周组织得到完全的修复再生，真正的牙周再生要求形成新的牙骨质和牙槽骨，并且有新生的牙周膜纤维嵌入并连接新生的牙骨质和骨组织。由于牙周支持组织结构和功能的复杂性，牙周再生治疗非常具有挑战性。以干细胞为基础的组织再生技术有望实现牙周再生。本研究将人牙龈成纤维细胞来源的非整合iPSCs成功分化为MSCs（iPSC-MSCs），证实iPSC-MSCs在体外rhGDF-5的作用下具有向牙骨质细胞方向分化的潜能；制备能够有效促进组织再生的三维纳米微球多孔结构，将其作为iPSC-MSCs的载体，制造免疫缺陷大鼠的牙周缺损模型，将能够缓释rhGDF-5的纳米微球多孔结构以及iPSC-MSCs植入体内缺损部位，评价动物体内实现牙周组织再生的效果。通过体外定向分化及植入牙周组织缺损模型的体内再生效果评价，为牙周再生提供新的策略。