A polymer-extracellular matrix composite with improved thromboresistance and recellularization properties

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Decellularized scaffolds offer a solution to donor organ shortages in organ engineering.
• Thrombosis in small vessels of these scaffolds limits their clinical application due to exposed extracellular matrix (ECM) components.
• Incomplete recellularization leads to adverse interactions with blood components.

Purpose of the Study:

• To design and evaluate a polymer-ECM composite to mitigate thrombosis in decellularized vascular scaffolds.
• To assess the composite's ability to reduce platelet adhesion and inhibit blood clotting.
• To investigate the composite's potential for facilitating re-endothelialization.

Main Methods:

• Rat aortas were decellularized, achieving 96.5% DNA removal while preserving ECM and mechanical properties.
• A biodegradable poly(1,8 octanediol citrate) (POC) elastomer was infused into the ECM and functionalized with heparin.
• The polymer-ECM composite's effects on platelet adhesion and whole blood clotting were evaluated in vitro.

Main Results:

• The POC-ECM composite significantly reduced platelet adhesion by up to 82.7%.
• Whole blood clotting was inhibited by up to 87.0% compared to untreated ECM.
• The composite supported endothelial cell adhesion in vitro, indicating potential for re-endothelialization.

Conclusions:

• The novel heparin-functionalized POC-ECM composite effectively reduces thrombosis in decellularized scaffolds.
• This biomaterial composite shows promise for improving the functionality of vascular grafts in tissue engineering.
• The findings suggest a potential solution for thrombosis complications in engineered vascular conduits.