Expanded 3D Nanofiber Scaffolds: Cell Penetration, Neovascularization, and Host Response

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Nanofiber scaffolds are crucial in tissue engineering.
• Controlling scaffold architecture is key for biological interaction.
• Existing methods may limit scaffold expansion and integration.

Purpose of the Study:

• To develop a method for fabricating expanded nanofiber scaffolds with controlled dimensions.
• To investigate the in vivo biological response to expanded nanofiber scaffolds.
• To evaluate the potential of these scaffolds for tissue repair and regeneration.

Main Methods:

• Fabrication of nanofiber scaffolds using a modified gas-foaming process with a custom mold.
• Computational fluid modeling to simulate scaffold expansion.
• Subcutaneous implantation of expanded and non-expanded scaffolds in rats.
• Histological analysis and cell marker quantification (CD68, CD163, CCR7) post-implantation.

Main Results:

• Expanded nanofiber scaffolds demonstrated significantly enhanced cellular infiltration compared to non-expanded scaffolds.
• Increased presence of macrophages (CD68+, CD163+) and T cells (CCR7+) within expanded scaffolds.
• Evidence of neovascularization (new blood vessel formation) at week 2 post-implantation.
• Heterogeneous multinucleated giant cells expressing macrophage markers were observed.

Conclusions:

• The developed expanded nanofiber scaffolds promote robust cellular infiltration and tissue integration.
• These scaffolds facilitate a regenerative response, including macrophage recruitment and neovascularization.
• Expanded electrospun nanofiber scaffolds represent a promising platform for in situ tissue regeneration and 3D tissue model development.