Paracrine Factor Local Gradient-Generating System for Engineering Perfusable Vascularized Hepatocyte Tissues with...

Area of Science:

• Biomedical Engineering
• Regenerative Medicine
• Hepatology

Background:

• Donor organ shortages necessitate engineered liver tissues.
• Vascular integration is a key challenge in liver tissue engineering.
• Achieving perfusable microvessels within engineered tissues remains difficult.

Purpose of the Study:

• To develop a system for creating vascularized, perfusable hepatocyte tissues.
• To recapitulate perfusion-mediated proliferative activity of primary hepatocytes in vitro.
• To overcome limitations in current liver tissue engineering vascularization strategies.

Main Methods:

• A paracrine factor local gradient (PFLG)-generating system was developed.
• Fibroblast-loaded cryogels were integrated with a microfluidic device.
• Angiogenesis was directed prior to hepatocyte seeding to enable microvessel penetration.

Main Results:

• Microvessels successfully penetrated the 3D hepatocyte tissue, mimicking in vivo architecture.
• Engineered tissues showed enhanced hepatocyte polarity and functional bile canaliculi.
• Perfusion culture significantly induced hepatocyte proliferation (increased Ki67-positive cells) without polarity loss.

Conclusions:

• Perfusion-mediated cues are critical for inducing hepatocyte cell-cycle re-entry while maintaining polarity.
• The developed platform supports vascularized, functional liver tissue engineering.
• This modular system provides a foundation for scalable, transplantable liver tissues.