A method to cleave target molecules in a neocartilage.

Area of Science:

• Biomaterials Science
• Biochemistry
• Tissue Engineering

Background:

• Determining the mechanical function of extracellular matrix molecules is crucial for understanding tissue properties.
• Traditional methods rely on specific enzymes to digest molecules, but suitable enzymes are unavailable for many candidates.
• This limitation hinders the evaluation of potential load-bearing structural molecules.

Purpose of the Study:

• To introduce a novel method for evaluating the mechanical function of matrix molecules when specific lytic enzymes are absent.
• To demonstrate the utility of this method using decorin and its dermatan sulfate glycosaminoglycan chain in engineered neocartilage.

Main Methods:

• Engineered a target molecule (decorin) with an inserted thrombin cleavage site.
• Expressed the engineered decorin in cells within a neocartilage tissue construct.
• Performed mechanical testing, followed by thrombin digestion to remove the glycosaminoglycan chain, and retested mechanical properties.

Main Results:

• Decorin protein was successfully expressed and localized within the engineered neocartilage.
• Thrombin digestion effectively removed the dermatan sulfate glycosaminoglycan chain from decorin.
• No significant changes in tissue mechanical properties (tension and compression) were observed after thrombin digestion.

Conclusions:

• The developed method allows for the functional assessment of matrix molecules lacking specific enzymatic cleavage sites.
• Decorin's dermatan sulfate chain does not appear to be essential for the mechanical integrity of this engineered neocartilage model.
• This approach supports the investigation of numerous candidate structural molecules in tissue engineering and biomaterials research.