Intraoperative bioprinting of composite tissues with zonal stratification for craniomaxillofacial reconstruction

项目摘要/摘要 目前修复颅颌面(CMF)缺损的方法具有一定的局限性。 CMF缺陷的无缝重建是非常具有挑战性的，因为多个 组织隔间不是微不足道的。这种划分需要精确和有效地使用 干细胞和分化因子，并将干细胞分化为多个谱系是至关重要的，以便 概括一下天然的组织解剖学。随着三维(3D)生物打印、重建 由于3D生物打印使复合体能够实现复合体，原位复合组织用于CMF修复最近变得可行 组织异质性在解剖学上的准确性和美观上的吸引力。术中 生物打印，这可以被定义为在手术中直接生物打印到缺损区以修复损伤 设置是一种高效的CMF重建过程，其中可以快速地提取缺陷信息 只需最少的人工干预即可获得，实现了准确的个性化重建 缺陷的表征。在这个项目中，我们假设术中生物打印的多层 携带分化因子的复合组织，包括microRNA(MiRNA)转染人 造血祖细胞和脂肪来源的细胞外基质成分(AdECM)诱导 软组织和硬组织，重述了无性系大鼠模型上的CMF组织解剖。为了测试我们的 假设，具体目的我将使用术中骨组织生物打印来揭示miR-148B- 以不同剂量转染人脂肪源性干细胞(ADSCs)促进骨组织再生。在……里面 具体目标二，我们将在术中活检多层皮肤组织，包括脂肪层和真皮层，在 目的探讨人ADSCs和ADECM成分在不同条件下本地化输送的影响。 剂量和浓度对皮肤组织再生的影响。特别是，我们将观察ADSC是否 分化为脂肪细胞，并了解脂肪层的存在对真皮的影响 再生。在特定的目标III中，我们将术中活组织打印三层复合组织，包括 颅层、脂肪层和真皮层，以了解血管化在软硬组织中的作用 再生。此外，我们还将探讨miR-210在血管形成中的作用。在这方面，我们已经成立了 一个互补的合作，融合了生物打印、再生医学、 CMF手术、整形外科手术、基因治疗、基因传递、骨力学以及骨和皮肤生物学 推动拟议工作取得有意义进展所需的深度，否则这些进展将不会 有可能。拟议工作的成功完成预计将带来先进的生物打印 揭示工程组织分层之间复杂相互作用的技术 免疫缺陷啮齿动物模型，从而提供了一种新的理解如何局部传递 分化因素影响颅颌面重建。

PROJECT SUMMARY/ABSTRACT Current approaches in repairing craniomaxillofacial (CMF) defects possess several limitations and the reconstruction of CMF defects seamlessly is highly challenging, as precise layer-by-layer stacking of multiple tissue compartments is not trivial. Such compartmentalization necessitates the precision and effective use of stem cells and differentiation factors, and differentiating stem cells into multiple lineages is crucial in order to recapitulate the native tissue anatomy. With the advances in three-dimensional (3D) bioprinting, reconstruction of composite tissues in situ for CMF repair has recently become feasible as 3D bioprinting enables complex tissue heterogeneity in an anatomically accurate and cosmetically appealing manner. Intraoperative bioprinting, which can be defined as bioprinting directly into the defect area for repairing injuries in a surgery setting, is a highly effective process for CMF reconstruction, where the defect information can be rapidly acquired with minimum manual interventions, enabling accurate personalized reconstructions immediately after characterization of the defect. In this project, we hypothesize that intraoperatively bioprinted multi-layer composite tissues loaded with differentiation factors including microRNA(miRNA)-transfected human progenitor cells and adipose-derived extracellular matrix components (adECM) induce compartmentalization of soft and hard tissues that recapitulates CMF tissue anatomy on an athymic rat model. In order to test our hypothesis, Specific Aim I will use intraoperative bone tissue bioprinting to reveal the impact of miR-148b- transfected human adipose-derived stem cells (ADSCs) at respective dosages on bone tissue regeneration. In Specific Aim II, we will intraoperatively bioprint multi-layer skin tissues, including adipose and dermis layers, in order to explore the impact of localized delivery of human ADSCs and adECM components at different dosages and concentrations on skin tissue regeneration, respectively. Particularly, we will observe if ADSCs differentiate into adipocytes and also understand the impact of the presence of adipose layer on dermis regeneration. In Specific Aim III, we will intraoperatively bioprint three-layer composite tissues, including cranium, adipose and dermis layers, in order to understand the role of a vascularization on soft and hard tissue regeneration. In addition, we will explore the role of miR-210 in vascularization. In this regard, we have formed a complementary collaboration that merges essential domain knowledge in bioprinting, regenerative medicine, CMF surgery, plastic surgery, gene therapy, gene delivery, bone mechanics, and bone and skin biology with the depth necessary to propel the proposed work towards meaningful advances that would otherwise not be possible. Successful completion of the proposed work is anticipated to give rise to an advanced bioprinting technology revealing the complex interactions between stratified layers of engineered tissues in an immunodeficient rodent model and thereby provide a novel understanding of how localized delivery of differentiation factors impacts craniomaxillofacial reconstruction.