Hydrogel-complexed small-diameter vascular graft loaded with tissue-specific vascular extracellular matrix components...

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Small diameter vascular grafts (SDVG) are crucial for treating vascular diseases, with tissue engineering offering promising solutions.
• Incorporating natural substances into synthetic SDVGs can enhance biocompatibility and in vivo regeneration.
• Variability in natural material properties necessitates source determination for optimizing SDVG fabrication.

Purpose of the Study:

• To fabricate bioactive SDVGs using vascular extracellular matrix (VECM) components for improved vascular regeneration.
• To evaluate the in vitro and in vivo performance of VECM-coated SDVGs compared to controls.

Main Methods:

• Bioactive SDVGs were created by coating heparin-modified poly-(ε-caprolactone) scaffolds with VECM precursor solution and in situ gelation.
• Mechanical properties, degradation, and morphology were characterized.
• In vitro cell proliferation assays and in vivo implantation studies in rat abdominal aortas were conducted.

Main Results:

• VECM promoted endothelial cell proliferation in vitro, outperforming skin-derived collagen.
• VECM-SDVGs demonstrated superior endothelium regeneration, appropriate intima formation, and no calcification in short-term implantation.
• Long-term implantation (6-12 months) showed a complete endothelial layer and near-native smooth muscle cell regeneration.

Conclusions:

• Vascular extracellular matrix exhibits tissue specificity, enhancing vascular graft regeneration.
• VECM-coated SDVGs (VECM-SDVGs) effectively modulate in vivo regenerative behavior.
• VECM-SDVGs offer a promising strategy for achieving satisfactory short- and long-term vascular regeneration.