Biodegradable sponges for hepatocyte transplantation

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Hepatology

Background:

• Liver cell transplantation is a potential therapy for liver tissue replacement.
• Current limitations include the need for effective delivery devices and methods to guide tissue integration.
• Biodegradable scaffolds are being explored to address these challenges.

Purpose of the Study:

• To evaluate poly-L-lactic acid (PLA) sponges infiltrated with polyvinyl alcohol (PVA) as a scaffold for hepatocyte delivery and liver tissue regeneration.
• To assess the sponges' properties for cell seeding and their performance in vivo.

Main Methods:

• Highly porous (90-95%) PLA sponges were fabricated using particulate leaching.
• Sponges were infiltrated with PVA to enhance hydrophilicity and facilitate cell seeding.
• Hepatocytes were seeded onto the sponges, and seeded devices were implanted into the mesentery of rats.

Main Results:

• PVA infiltration reduced the contact angle of PLA sponges, improving water absorption and enabling even, high-density hepatocyte seeding (5 x 10^7 cells/mL).
• Following implantation, approximately 6 x 10^5 hepatocytes engrafted per sponge.
• In vivo, fibrovascular tissue invaded the sponges, forming a composite tissue of hepatocytes, blood vessels, and fibrous tissue within the scaffold.

Conclusions:

• PLA-PVA sponges are suitable scaffolds for hepatocyte transplantation, demonstrating good cell adherence, seeding efficiency, and in vivo engraftment.
• The porous structure supports fibrovascular tissue integration, indicating potential for guided liver tissue regeneration.