Three dimensional polyvinyl alcohol scaffolds modified with collagen for HepG2 cell culture

Abstract

The creation of in vitro functional hepatic tissue simulating micro environmental niche of the native liver is a keen area of research due to its demand in bioartificial liver. However, it is still unclear how to maintain benign cell function while achieving the sufficient cell quantity. In this work, we aim to prepare a novel scaffold for the culture of HepG2 cells, a liver cell line, by modifying polyvinyl alcohol (PVA) scaffold with collagen (COL). PVA is a kind of synthetic biostable polymer with high hydrophilicity in the human body, has been widely used in the biomedical field. However, the use of PVA is limited in cell cultures due to lack of biologically active functional groups. In this study, amino silane (KH-550), glutaraldehyde and native type I collagen were used to modify three-dimensional PVA scaffold to establish a suitable composite scaffold for hepatocyte culture. Three types of composite scaffolds were prepared for different collagen content, named as PVA/COL (0.2%), PVA/COL (0.5%) and PVA/COL (0.8%), respectively. The composite scaffolds were characterized by SEM, XPS, FTIR, MS, porosity estimation and water contact angle measurement. The PVA/COL (0.8%) scaffolds had the highest collagen content of 12.13%. The composite scaffold showed high porosity with interconnected pores. Furthermore, the biocompatibility between HepG2 cells and scaffolds was evaluated by the ability of cell proliferation, albumin secretion, as well as urea synthesis. The coating of collagen on PVA scaffolds promoted hydrophilicity and HepG2 cell adhesion. Additionally, enhanced cell proliferation, increased albumin secretion and urea synthesis were observed in HepG2 cells growing on collagen-coated three-dimensional PVA scaffolds.

Gelatin-Based Hybrid Hydrogel Scaffolds: Toward Physicochemical Liver Mimicry

“…Other 3D-constructs involve the use of hydrogel scaffolds (e.g., alginate dialdehyde-gelatin, gelatin methacryloyl, and collagen/chitosan), in combination with primary human hepatocytes (PHH), , primary rat hepatocytes, or hepatic cell lines. , Those constructs exhibit a decreasing viability and functionality over time, leading to a limited or discontinued secretion of important metabolic enzymes that render them inappropriate toward hepatocyte support, mainly due to inadequate resemblance with the native liver’s physicochemical properties. , …”

The native liver as inspiration to create superior in vitro hepatic models

“…103 Often used coating compounds in this regard include laminin, Fibronectin and collagen. [104][105][106] Alternative strategies described in literature include the application of decellularized native ECM (dECM) compounds used as biomaterial ink for scaffold fabrication/ printing or the decellularization and subsequent recellularization of natural liver tissue matrix. Although these strategies show significant improvement of hepatocyte function and generation of complex multicellular models, 107,108 they are not suitable to realize high throughput toxicity screening models.…”

A Review of Recent Progress on Collagen‐Based Biomaterials

“…Researchers have investigated multiple types tissueengineered products, including artificial blood vessels, [212,213] tendons, [214] cartilages, [215,216] livers. [217,218] So far, Apligraf, Dermahave, and Carticle were approved by the Food and Drug Administration (U.S.), whereas Antifu, Bio-Gene, and Bio-Tendon were approved by the National Medical Products Administra- tion (China). Collagen is widely used in tissue engineering fields such as bone/cartilage tissue engineering, skin tissue engineering, neural tissue engineering, and tendon tissue engineering after proper modification with multifunctional biological small molecules or macromolecules, biocompatible polymers, and other bioactive materials.…”