Scaffolds for engineering smooth muscle under cyclic mechanical strain conditions

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Cellular Mechanics

Background:

• Cyclic mechanical strain improves engineered smooth muscle (SM) tissue development and function.
• Existing scaffolds often lack the necessary elastic properties for effective SM tissue engineering under dynamic conditions.
• Scaffolds must induce appropriate smooth muscle cell (SMC) phenotypes in response to mechanical cues.

Purpose of the Study:

• To characterize commonly used tissue engineering scaffolds for their elastic properties under cyclic strain.
• To evaluate the ability of selected scaffolds to promote an appropriate SMC phenotype in engineered SM tissues under cyclic strain.

Main Methods:

• Characterization of scaffold mechanical properties, including elasticity and permanent deformation, under cyclic strain.
• Analysis of SMC phenotype and tissue composition (e.g., elastin content) in engineered SM tissues cultured on different scaffolds with cyclic strain.

Main Results:

• Type I collagen sponges and poly(L-lactic acid)-bonded polyglycolide scaffolds showed partial elasticity, but synthetic scaffolds exhibited permanent deformation.
• SM tissues engineered with type I collagen sponges under cyclic strain had increased elastin and SMCs with a contractile phenotype.
• Control tissues and tissues on synthetic scaffolds showed SMCs with a synthetic, non-differentiated phenotype.

Conclusions:

• Scaffold selection for mechanically dynamic tissue engineering depends on the duration of mechanical stimulation.
• Elastic scaffolds enable mechanically directed control over cell phenotype in engineered tissues.
• Type I collagen sponges are suitable for engineering SM tissues requiring a contractile phenotype under cyclic strain.