Rapid casting of patterned vascular networks for perfusable engineered three-dimensional tissues

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Three-dimensional (3D) engineered tissues often suffer from central necrosis due to the lack of functional vascular networks.
• Developing methods for rapid and general construction of perfusable vascular systems in 3D tissue constructs is a significant challenge.

Purpose of the Study:

• To present a novel, versatile approach for fabricating perfusable vascular networks within 3D engineered tissues.
• To demonstrate the capability of this method to support cell viability and function in engineered tissues.

Main Methods:

• Printing rigid 3D filament networks from carbohydrate glass as sacrificial templates.
• Utilizing these templates within engineered tissues containing living cells to create vascular channels.
• Lining the channels with endothelial cells and perfusing them with blood under pulsatile flow.

Main Results:

• Successful generation of perfusable cylindrical vascular networks using the sacrificial template method.
• Demonstrated compatibility with diverse cell types, extracellular matrices, and crosslinking strategies.
• Maintained metabolic function of primary rat hepatocytes in engineered tissues via perfused vascular channels.

Conclusions:

• This vascular casting approach provides independent control over network geometry, endothelialization, and extravascular tissue.
• The method effectively overcomes core necrosis in 3D engineered tissues by establishing functional vasculature.
• The technique holds promise for advancing the development of complex, metabolically active engineered tissues.