Packed‐Bed Type Reactor to Attain High Density Culture of Hepatocytes for Use as a Bioartificial Liver

Abstract

In an attempt to develop a bioartificial liver using cultured hepatocytes, we investigated the short-term and long-term viability and metabolic functions of hepatocytes cultured in a new type of packed-bed type reactor using reticulated polyvinyl formal (PVF) resin as a supporting material. Perfusion culture experiments using this reactor, as well as monolayer cultures using conventional collagen-coated Petri dishes as control experiments, were performed. It was found that the highest density of immobilized hepatocytes attained with PVF resin was on the order of lo7 cells/cm3 PVF and that hepatocytes cultured in this type of module for up to a week showed a sufficient level of liver-specific metabolic functions, such as ammonium metabolism, urea-N synthesis, and albumin secretion, to be comparable to those in the monolayer culture. It is concluded that the packed-bed reactor system utilizing PVF resin is a promising means to develop a bioartificial organ using hepatocytes.

Integration of Technologies for Hepatic Tissue Engineering

“…Designs include hepatocytes cultured on polyvinyl formal resin [107], entrapped in alginate particles [108], or hepatocyte aggregates packed between silica beads [109]. One interesting design, introduced by investigators at MIT, is a microfabricated array bioreactor (Fig.…”

“…Wells are 300 µm wide and 235 µm in height, designed for physiological shear [110,111]. Hepatocyte aggregates seeded in packed-bed reactors such as the one described maintain albumin and urea secretion as well as cytochrome P450 activity for weeks in culture [107][108][109]112]. The microfabricated array bioreactor was more recently used to study drug toxicity and hepatitis B virus infection [113].…”

Medical Devices

“…In a bioartificial liver device, the animal or human liver cells can conceivably be cultured and used in several forms, including (i) independent single-cell suspensions; (ii) spheroid (i.e., globular) aggregates of cells of 100-150 μm diameter; (iii) cylindroid, rod-like aggregates of cells of 100-150 μm diameter; (iv) encapsulated cells; and (v) cells attached to solid surfaces, such as microcarriers, flat surfaces, and the inside or outside of hollow fibers. Here, the hepatocytes are cultured on the inside surfaces of small pieces of highly porous resin that are packed randomly in a vertical cylindrical reactor [21]. Among the various types of bioartificial liver devices tested to date, four distinct groups can be identified [19]: 1) Hollow Fibers.…”

Cells, scaffolds and bioreactors for tissue-engineered heart valves: a journey from basic concepts to contemporary developmental innovations☆

“…The simplest examples for this category are represented by common and/or modified Petri dishes or multiwell plates on which the acellular scaffold (biological or biopolymeric) is cultured after cell seeding in nonstirred conditions or by means of packed-bed reactors with porous substrate to perfuse the culture [57]. Cell culture tests have also been performed in both microgravity and zero-gravity environments [58] using specific bioreactors to investigate the activity and proliferation of microorganisms.…”