Chuang Chia-Hui, Lin Ruei-Zeng, Tien Han-Wen, Chu Ya-Chun, Li Yen-Cheng, Melero-Martin Juan M, Chen Ying-Chieh
Department of Applied Science, National Hsinchu University of Education, Hsinchu 30014, Taiwan, ROC.
Department of Cardiac Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.
Acta Biomater. 2015 Jun;19:85-99. doi: 10.1016/j.actbio.2015.02.024. Epub 2015 Mar 6.
To manufacture tissue engineering-based functional tissues, scaffold materials that can be sufficiently vascularized to mimic the functionality and complexity of native tissues are needed. Currently, vascular network bioengineering is largely carried out using natural hydrogels as embedding scaffolds, but most natural hydrogels have poor mechanical stability and durability, factors that critically limit their widespread use. In this study, we examined the suitability of gelatin-phenolic hydroxyl (gelatin-Ph) hydrogels that can be enzymatically crosslinked, allowing tuning of the storage modulus and the proteolytic degradation rate, for use as injectable hydrogels to support the human progenitor cell-based formation of a stable and mature vascular network. Porcine gelatin-Ph hydrogels were found to be cytocompatible with human blood-derived endothelial colony-forming cells and white adipose tissue-derived mesenchymal stem cells, resulting in >87% viability, and cell proliferation and spreading could be modulated by using hydrogels with different proteolytic degradability and stiffness. In addition, gelatin was extracted from mouse dermis and murine gelatin-Ph hydrogels were prepared. Importantly, implantation of human cell-laden porcine or murine gelatin-Ph hydrogels into immunodeficient mice resulted in the rapid formation of functional anastomoses between the bioengineered human vascular network and the mouse vasculature. Furthermore, the degree of enzymatic crosslinking of the gelatin-Ph hydrogels could be used to modulate cell behavior and the extent of vascular network formation in vivo. Our report details a technique for the synthesis of gelatin-Ph hydrogels from allogeneic or xenogeneic dermal skin and suggests that these hydrogels can be used for biomedical applications that require the formation of microvascular networks, including the development of complex engineered tissues.
为制造基于组织工程的功能性组织，需要能够充分血管化以模拟天然组织的功能和复杂性的支架材料。目前，血管网络生物工程主要使用天然水凝胶作为包埋支架来进行，但大多数天然水凝胶的机械稳定性和耐久性较差，这些因素严重限制了它们的广泛应用。在本研究中，我们研究了可通过酶交联来调节储能模量和蛋白水解降解速率的明胶-酚羟基（gelatin-Ph）水凝胶作为可注射水凝胶以支持基于人类祖细胞形成稳定且成熟的血管网络的适用性。发现猪明胶-Ph水凝胶与人血源性内皮集落形成细胞和白色脂肪组织源性间充质干细胞具有细胞相容性，细胞活力>87%，并且通过使用具有不同蛋白水解降解性和硬度的水凝胶可调节细胞增殖和扩散。此外，从小鼠真皮中提取明胶并制备了小鼠明胶-Ph水凝胶。重要的是，将负载人类细胞的猪或小鼠明胶-Ph水凝胶植入免疫缺陷小鼠体内会导致生物工程化的人类血管网络与小鼠脉管系统之间迅速形成功能性吻合。此外，明胶-Ph水凝胶的酶交联程度可用于调节体内细胞行为和血管网络形成的程度。我们的报告详细介绍了一种从同种异体或异种皮肤合成明胶-Ph水凝胶的技术，并表明这些水凝胶可用于需要形成微血管网络的生物医学应用，包括复杂工程组织的开发。
