Coculture Method to Obtain Endothelial Networks Within Human Tissue-Engineered Skeletal Muscle

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Skeletal muscle tissue engineering seeks to create functional muscle constructs in vitro.
• Current limitations in construct thickness are due to passive nutrient and oxygen diffusion.
• Integrating vascular networks is crucial for overcoming diffusion limitations in engineered tissues.

Purpose of the Study:

• To engineer in vitro skeletal muscle constructs with aligned human myofibers and interspersed endothelial networks.
• To develop a bio-artificial muscle (BAM) that overcomes diffusion limitations for thicker tissue engineering.

Main Methods:

• Co-culture of human muscle progenitor cells and human umbilical vein endothelial cells (HUVECs) in a fibrin hydrogel.
• Casting the cell-gel mixture into silicone molds with end attachment sites.
• Culture in endothelial growth medium (EGM-2) for one week, allowing passive forces to align myogenic cells.

Main Results:

• Formation of aligned, multinucleated myofibers due to cell alignment and fusion.
• Development of interspersed endothelial networks within the muscle construct.
• Successful creation of a ~1.5 mm thick, 2 cm long human bio-artificial muscle (BAM) construct.

Conclusions:

• This study demonstrates a novel method for engineering vascularized skeletal muscle tissue in vitro.
• The developed bio-artificial muscle (BAM) constructs show potential for regenerative medicine and as models for myogenesis and myopathology.
• Integration of endothelial networks successfully addresses diffusion limitations, enabling thicker tissue development.