Biofabrication of Hepatic Constructs by 3D Bioprinting of a Cell‐Laden Thermogel: An Effective Tool to Assess Drug‐Induced Hepatotoxic Response

Abstract

A thermoresponsive Pluronic/alginate semisynthetic hydrogel is used to bioprint 3D hepatic constructs, with the aim to investigate liver-specific metabolic activity of the 3D constructs compared to traditional 2D adherent cultures. The bioprinting method relies on a bioinert hydrogel and is characterized by high-shape fidelity, mild depositing conditions and easily controllable gelation mechanism. Furthermore, the dissolution of the sacrificial Pluronic templating agent significantly ameliorates the diffusive properties of the printed hydrogel. The present findings demonstrate high viability and liver-specific metabolic activity, as assessed by synthesis of urea, albumin, and expression levels of the detoxifying CYP1A2 enzyme of cells embedded in the 3D hydrogel system. A markedly increased sensitivity to a well-known hepatotoxic drug (acetaminophen) is observed for cells in 3D constructs compared to 2D cultures. Therefore, the 3D model developed herein may represent an in vitro alternative to animal models for investigating drug-induced hepatotoxicity.

Current Advances in 3D Bioprinting Technology and Its Applications for Tissue Engineering

“…Owing to the use of autologous MSCs, the cell-laden artificial structure was confirmed to have obtained better endothelialization with little inflammation. [193] gelatin. Consequently, high cell density showed a more liquefied bio-ink in the work of Freeman et al Recently, Jang et al biofabricated a vascular scaffold (inner diameter: 4 mm, outer diameter: 5 mm, length: 40 mm) using two different bio-inks: alginate and PCL [188].…”

“…The results showed that the cell viability, level of liver functional activities of albumin and blood urea nitrogen, and porosity were significantly higher than those in the absence of dECM. Gori et al biofabricated a porous structure using composite bio-inks composed of PF127 and alginate [193]. They found printed 3D structures had better liver functional metabolism activity when comparing with the 2D cell adherent method.…”

Colonization versus encapsulation in cell-laden materials design: porosity and process biocompatibility determine cellularization pathways

“…Nowadays, these materials are obtained using colonization of hydrogels [252] or three-dimensional printed constructs [253], or by cell encapsulation in hydrogels [254,255] with tuneable mechanical properties [252,256,257], three-dimensional printed gels [258] or microbeads [259]. Moreover, recent bioinspired scaffolds based on cell encapsulation in hydrogels have enabled to model angiogenesis [260], the osteochondral environment [261], bone [262], brain [263], gastric mucosa [264], and the liver [265]. The constant evolution of the materials processing techniques will continue to expand the cellularization pathways available to design new, more relevant healthy tissue models.…”

Bioengineered Liver Models for Investigating Disease Pathogenesis and Regenerative Medicine

“…Hepatocyte viability and functions have been assessed with different bioinks 256,257 ; however, these printing processes required cells to be seeded after the 3D construct was printed, limiting the control over cell organization throughout the tissue. Therefore, printing methods that allow for the simultaneous printing of the cells within bioinks, including HA in combination with gelatin, 258 collagen, 259 or alginate, [260][261][262][263] have provided the ability to fabricate more complex tissues that better mimic the liver microenvironment by controlling cellular placement.…”