3D-printed gelatin scaffolds of differing pore geometry modulate hepatocyte function and gene expression

Area of Science:

• Biomaterials Engineering
• Tissue Engineering
• Cell Biology

Background:

• Three dimensional (3D) printing offers precise control over scaffold architecture for tissue engineering.
• The impact of specific scaffold geometries on hepatocyte function remains underexplored.
• Controlling cellular aggregation and nutrient diffusion is crucial for engineered tissues.

Purpose of the Study:

• To investigate the effect of varying 3D-printed scaffold geometries on hepatocyte function, while controlling for pore size.
• To assess hepatocyte viability, proliferation, and specific functions in response to different 3D-printed gelatin scaffold designs.
• To compare the performance of 3D cultures with traditional 2D cultures.

Main Methods:

• Fabrication of gelatin scaffolds with precisely controlled, repetitive pore geometries using 3D printing.
• Seeding of undifferentiated hepatocyte cell line (HUH7) onto 3D scaffolds and 2D controls.
• Assessment of cell viability, proliferation, albumin secretion, CYP activity, and bile transport.
• Analysis of gene expression and protein function.

Main Results:

• HUH7 cells exhibited high viability and proliferation on 3D-printed scaffolds of different geometries.
• Hepatocyte-specific functions (albumin secretion, CYP activity, bile transport) were significantly increased in more interconnected 3D scaffolds compared to less interconnected ones.
• A disparity between gene expression and protein function was observed in 2D cultures, which was mitigated in 3D environments.

Conclusions:

• 3D-printed gelatin scaffolds with controlled pore geometry can significantly modulate hepatocyte function.
• Interconnected scaffold architectures are superior to less interconnected ones and 2D cultures for promoting hepatocyte-specific functions.
• A physiologically mimetic 3D environment is essential for inducing both gene expression and protein function in cultured hepatocytes.