Mimicking Physiologically Relevant Hepatocyte Zonation Using Immunomodulatory Silk Liver Extracellular Matrix Scaffolds toward a Bioartificial Liver Platform

Abstract

Mimicking nativelike metabolic zonation is indispensable to develop an efficient bioartificial liver model, as it facilitates physiological cues, hepatocyte polarity, and phenotypic functions. The present study shows the first evidence of hepatocyte metabolic heterogeneity in an in vitro liver model encompassing liver extracellular matrix (ECM)-functionalized silk scaffolds (LECM-SF) by altering ECM proportion. Upon static culture, individual LECM-SF scaffold supports differential synthetic and metabolic functions of cultured primary neonatal rat hepatocytes (PNRHs), owing to discrete biophysical attributes. A single in vitro liver system comprising PNRHs seeded LECM-SF scaffolds assisting periportal to pericentral gradient functions is stacked and matured in a perfusion bioreactor to simulate oxygen gradient. The scaffold with high ECM supports periportal-specific albumin synthesis, urea secretion, and bile duct formation, albeit scaffold with low ECM supports pericentral-specific cytochrome P450 activity. Extensive physicochemical characterizations confirmed the stability and interconnected porous network of scaffolds, signifying cellular infiltration and bidirectional nutrient diffusion. Furthermore, scaffolds demonstrate minimal thrombogenicity, reduced foreign-body response, and enhanced pro-remodeling macrophage activation, supporting constructive tissue remodeling. The developed liver model with zone-specific functions would be a promising avenue in bioartificial liver and drug screening.

Temporal dynamics of metabolic acquisition in grafted engineered human liver tissue

“…Intensive engineered devices that establish gradients of nutrients or oxygen exposure are necessary to study human zonation in vitro. [35][36][37][38][39][40][41][42][43][44][45][46][47] To our knowledge, this is the first report of an engineered human-derived zonated phenotype in vivo. Future studies could leverage this system to uncover mechanisms of both human hepatocyte expansion and zonation in vivo or to create zonated human liver tissues for the treatment of liver disease.…”

Silk‐Based Bioengineered Diaphyseal Cortical Bone Unit Enclosing an Implantable Bone Marrow toward Atrophic Nonunion Grafting

“…The HSC seeded TEBN was matured in perfusion bioreactor (3D Biotek, USA) under operating conditions previously described. [ 45 ] Briefly, two HSC seeded TEBN (from one group either BMC or BAC) were stacked per polycarbonate chamber separated by sterile O‐rings, with a flow rate of 0.5 mL min −1 equilibrated with 50 mL maturation media in media reservoirs, which was replenished 50% with fresh media every 7 days.…”

Bioinspired silk fibroin materials: From silk building blocks extraction and reconstruction to advanced biomedical applications

“…By using a complex RSF scaffold fabricated by blending mulberry ( Bombyx mori ) SF with cell adhesion motif contained non-mulberry ( Antheraea assamensis ) SF, Janani et al. generated a functional liver construct in vitro, which enhanced liver-specific functions of cultured hepatocytes according to the evaluation of albumin synthesis, urea synthesis and cytochrome P450 enzyme activity [ 157 , 158 ]. This kind of complex RSF scaffold offers a suitable microenvironment by influencing spheroidal growth of hepatocytes with enhanced biological activity.…”