State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang Province 310003, China.
Department of Bioengineering, University of California Berkeley, Berkeley, CA 94720, USA.
Biomater Sci. 2020 May 19;8(10):2814-2824. doi: 10.1039/c9bm01879d.
Although bioartificial liver support systems (BLSSs) play an essential role in maintaining partial liver functions and detoxification for liver failure patients, hepatocytes are unanimously seeded in biomaterials, which lack the hierarchal structures and mechanical cues of native liver tissues. To address this challenge, we developed a new BLSS by combining a decellularized liver matrix (DLM)/GelMA-based bioengineered whole liver and a perfusion-based, oxygenated bioreactor. The novel bioengineered whole liver was fabricated by integrating photocrosslinkable gelatin (GelMA) and hepatocytes into a DLM. The combination of GelMA and the DLM not only provided a biomimetic extracellular microenvironment (ECM) for enhanced cell immobilization and growth with elevated hepatic functions (e.g., albumin secretion and CYP activities), but also provided biomechanical support to maintain the native structure of the liver. In addition, the perfusion-based, oxygenated bioreactor helped deliver oxygen to the interior tissues of the bioengineered liver, which was of importance for long-term culture. Most importantly, this new bioengineered whole liver decreased ammonia concentration by 45%, whereas direct seeding of hepatocytes in a naked DLM showed no significant reduction. Thus, the developed BLSS integrated with the DLM/GelMA-based bioengineered whole liver can potentially help elevate liver functions and prevent HE in liver failure patients while waiting for liver transplantation.
尽管生物人工肝脏支持系统 (BLSS) 在维持肝功能和肝脏衰竭患者的解毒方面发挥着重要作用,但肝细胞一致地种植在生物材料上,这些生物材料缺乏天然肝脏组织的层次结构和机械线索。为了解决这一挑战,我们开发了一种新的 BLSS,它将脱细胞肝脏基质 (DLM)/GelMA 基生物工程全肝和基于灌注的充氧生物反应器结合在一起。新型生物工程全肝是通过将光交联明胶 (GelMA) 和肝细胞整合到 DLM 中制成的。GelMA 和 DLM 的结合不仅为增强细胞固定和生长提供了仿生细胞外微环境 (ECM),并提高了肝脏功能(例如白蛋白分泌和 CYP 活性),而且为维持肝脏的天然结构提供了生物力学支持。此外,基于灌注的充氧生物反应器有助于向生物工程肝脏的内部组织输送氧气,这对于长期培养非常重要。最重要的是,这种新的生物工程全肝可将氨浓度降低 45%,而直接将肝细胞种植在裸露的 DLM 中则没有显著降低。因此,与 DLM/GelMA 基生物工程全肝集成的开发 BLSS 可以在等待肝移植的同时帮助提高肝脏功能并预防肝衰竭患者的肝性脑病。