Zhang Shanshan, Qi Cheng, Zhang Wei, Zhou Hui, Wu Nihuan, Yang Ming, Meng Si, Liu Zhou, Kong Tiantian
Department of Biomedical Engineering, School of Medicine, Shenzhen University, Shenzhen, Guangdong, 518000, China.
College of Mechatronics and Control Engineering, Shenzhen University, Shenzhen, Guangdong, 518000, China.
Adv Mater. 2023 Feb;35(7):e2209263. doi: 10.1002/adma.202209263. Epub 2022 Dec 18.
The challenge of bioprinting vascularized tissues is structure retention and in situ endothelialization. The issue is addressed by adopting an aqueous-in-aqueous 3D embedded bioprinting strategy, in which the interfacial coacervation of the cyto-mimic aqueous two-phase systems (ATPS) are employed for maintaining the suspending liquid architectures, and serving as filamentous scaffolds for cell attachment and growth. By incorporating endothelial cells in the ink phase of ATPS, tubular lumens enclosed by coacervated complexes of polylysine (PLL) and oxidized bacteria celluloses (oxBC) can be cellularized with a confluent endothelial layer, without any help of adhesive peptides. By applying PLL/oxBC ATPS for embedded bioprinting, free-form 3D vascular networks with in situ endothelialization of interconnected tubular lumens are achieved. This simple approach is a one-step process without any sacrificed templates and post-treatments. The resultant functional vessel networks with arbitrary complexity are suspended in liquid medium and can be conveniently handled, opening new routes for the in vitro production of thick vascularized tissues for pathological research, regeneration therapy and animal-free drug development.
生物打印血管化组织面临的挑战是结构保留和原位内皮化。通过采用水包水3D嵌入式生物打印策略来解决这个问题，其中细胞模拟水两相系统（ATPS）的界面凝聚用于维持悬浮液结构，并作为细胞附着和生长的丝状支架。通过将内皮细胞掺入ATPS的墨水相中，由聚赖氨酸（PLL）和氧化细菌纤维素（oxBC）的凝聚复合物包围的管状腔可以被汇合的内皮细胞层细胞化，而无需任何粘附肽的帮助。通过将PLL/oxBC ATPS应用于嵌入式生物打印，可以实现具有相互连接的管状腔原位内皮化的自由形式3D血管网络。这种简单的方法是一个一步过程，无需任何牺牲模板和后处理。所得的具有任意复杂性的功能性血管网络悬浮在液体介质中，便于操作，为体外生产用于病理研究、再生治疗和无动物药物开发的厚血管化组织开辟了新途径。
