Fabrication and Characterization of Heparin/Collagen Sponge for in Vitro Differentiation of Wharton's Jelly-Derived Mesenchymal Stem Cells into Hepatocytes

Recapitulating the native cell niche and extracellular matrix (ECM) architecture in vitro helps reconstruct injured tissues. Collagen I and heparin are two important constituents of the ECMs, which play crucial roles in regulating cell behaviors. Specifically in the liver, these components can affect the differentiation and functionality of the cells..
The aims of this study were to first fabricate and characterize a heparin/collagen scaffold and then investigate the scaffold’s efficiency in directing the differentiation of Wharton’s jelly-derived mesenchymal stem cells (WJ-MSCs) towards hepatocyte..
After fabricating the rat tail collagen I sponge-shaped scaffolds, heparin was chemically immobilized on the scaffolds using N-(3-dimethylaminopropyl)-N-ethylcarbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS). The scaffold chemical characteristics and architecture were evaluated by Fourier-transformed infrared (FTIR) spectroscopy and scanning electron microscopy (SEM), respectively. In the next step, Wharton’s jelly-derived mesenchymal stem cells were seeded on the scaffolds and cell viability and morphology were assessed using MTT assay and SEM, respectively. Moreover, followed by exposing the WJ-MSCs to the hepatogenic media for 3 weeks, liver-specific marker expression and indocyanine green (ICG) clearance tests were performed..
The data showed that 0.25 mg/mL heparin had no detrimental effects on the cell viability and proliferation compared to the observed effects in non-heparinized conditions. SEM micrographs showed that while immobilizing heparin had no considerable effect on the porosity of the scaffolds, the mean value of the pore sizes of heparinized sponges was higher than that of non-heparinized ones. The hepatocyte differentiation appeared to be enhanced in the cells cultured in heparinized sponges as indicated by higher percentage of the cells expressing cytokeratin 19 and albumin as well as improved indocyanine green clearance levels..
Heparin/collagen scaffold serves as a good platform for promoting differentiation into hepatocytes and therefore, it has the potential to be considered for drug discovery and liver regenerative medicine..