Leaflet Tissue Generation from Microfibrous Heart Valve Leaflet Scaffolds with Native Characteristics

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Cardiovascular Engineering

Background:

• Current mechanical and bioprosthetic heart valves have limitations.
• Heart valve tissue engineering offers a potential solution.
• Native heart valve leaflets possess a complex trilayered, oriented structure crucial for function.

Purpose of the Study:

• To develop microfibrous leaflet scaffolds that replicate the native trilayered, oriented structure of heart valve leaflets.
• To evaluate the in vivo efficacy of these scaffolds in generating functional tissue-engineered heart valve constructs.

Main Methods:

• Fabrication of microfibrous leaflet scaffolds using electrospinning to achieve a native trilayered and oriented structure.
• Subcutaneous implantation of scaffolds in rats for 3 months to assess tissue regeneration.
• Analysis of the structural, mechanical, and cellular properties of the in vivo generated tissue constructs.

Main Results:

• In vivo constructs exhibited a native-like trilayered, oriented structure.
• Tensile properties demonstrated the constructs' ability to withstand native heart valve hydrodynamic loads.
• Constructs contained sufficient native extracellular matrix components (collagen, glycosaminoglycans, elastin) and expressed cellular markers (vimentin, α-smooth muscle actin), indicating a viable, growing state.

Conclusions:

• The developed trilayered, oriented fibrous leaflet scaffolds are effective in generating functional tissue-engineered heart valve constructs in vivo.
• These scaffolds hold significant potential for the development of advanced heart valve replacements.