Cell-printed 3D liver-on-a-chip possessing a liver microenvironment and biliary system

Abstract

To overcome the drawbacks of in vitro liver testing during drug development, numerous liver-on-a-chip models have been developed. However, current liver-on-a-chip technologies are labor-intensive, lack extracellular matrix (ECM) essential for liver cells, and lack a biliary system essential for excreting bile acids, which contribute to intestinal digestion but are known to be toxic to hepatocytes. Therefore, fabrication methods for development of liver-on-a-chip models that overcome the above limitations are required. Cell-printing technology enables construction of complex 3D structures with multiple cell types and biomaterials. We used cell-printing to develop a 3D liver-on-a-chip with multiple cell types for co-culture of liver cells, liver decellularized ECM bioink for a 3D microenvironment, and vascular/biliary fluidic channels for creating vascular and biliary systems. A chip with a biliary fluidic channel induced better biliary system creation and liver-specific gene expression and functions compared to a chip without a biliary system. Further, the 3D liver-on-a-chip showed better functionalities than 2D or 3D cultures. The chip was evaluated using acetaminophen and it showed an effective drug response. In summary, our results demonstrate that the 3D liver-on-a-chip we developed is promising in vitro liver test platform for drug discovery.

Engineered Liver-On-A-Chip Platform to Mimic Liver Functions and Its Biomedical Applications: A Review

“…This printed liver organoid also showed higher albumin and cytochrome P450 expression compared with the monolayer control over 14 days of cultivation. Furthermore, Lee et al generated a 3D liver-on-a-chip with multiple cell types using decellularized ECM bio ink and integrated it with a microfluidic device containing vascular and biliary fluidic channels [10]. Their results demonstrated that the liver functionalities were significantly enhanced by the formation of the biliary system on a chip, which becomes an effective potential candidate for drug discovery.…”

“…Based on these facts, it is necessary to establish a reliable liver model in vitro for in-depth understanding of the physiological/pathological processes in the liver and the development of drugs for liver diseases. Currently, the liver models used for in vitro studies commonly include bioreactors (perfusion model of an isolated liver system) [7], 2D planar primary rat hepatocytes [8,9], 3D-printed liver tissue [10,11], liver organoids [12,13], and liver-on-a-chip systems [14][15][16]. To date, many previous reviews have discussed the differences in these models [17][18][19][20].…”

Fabrication of Muco-Adhesive Oral Films by the 3D Printing of Hydroxypropyl Methylcellulose-Based Catechin-Loaded Formulations

“…17) 3D bioprinters have been studied for possible applications in tissue engineering, for example by using hydrogel/paste-based materials to prepare cell-incorporated bioinks. The manufacture of skin and body parts using a 3D bioprinter holds promise for future transplantation therapy, 18) and 3D printing of organs-on-a-chip (e.g., liver) that can replicate organ-level functions which would transform the screening and testing of drugs. 19,20) Pharmaceutical applications of 3D bioprinters may allow the preparation of temperature-sensitive drugs and biopharmaceuticals by using a hydrogel/paste-based drug formulation 17) because bioprinters do not require high temperature, in contrast to typical 3D printers (e.g., the conventional fused deposition modeling (FDM)-type 3D printer used to prepare tablets).…”

Biofabrication Strategies and Engineered In Vitro Systems for Vascular Mechanobiology

“…Investigation of flow‐associated liver function and clearance has been conducted in vitro in several on‐chip platforms ( Figure ). [ 362,371–374 ] In particular, comparative studies of hepatocyte culture in static versus perfused conditions reveal the important role of flow in albumin and urea secretion, cytochrome P450 metabolism, toxicity modulation of drug compounds, liver zonation, and overall long‐term maintenance of hepatocyte viability. [ 285,375–377 ] One study uncovered the role of vessel perfusion in stretching of LSECs, activating integrin β 1 and vascular endothelial growth factor receptor 3 (VEGFR3), upregulating HGF secretion, and resulting in increased hepatocyte proliferation and survival.…”