PLGA nanometer surface features manipulate fibronectin interactions for improved vascular cell adhesion.

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Vascular Biology

Background:

• Atherosclerotic vascular disease is a leading cause of mortality, often necessitating synthetic vascular grafts.
• Small diameter (<6 mm) vascular grafts exhibit low patency rates (30% at 5 years), highlighting a critical need for improved graft materials.
• Current strategies involve random nanostructured surfaces to enhance vascular cell functions, but controlled nanostructure design is key.

Purpose of the Study:

• To formulate highly-controllable, ordered nanostructured surfaces on poly(lactic-co-glycolic acid) (PLGA).
• To investigate the effect of specific nanometer surface feature sizes on fibronectin spreading and vascular cell adhesion.
• To identify optimal nanostructure characteristics for enhancing small diameter vascular graft success.

Main Methods:

• Ordered nanostructured roughness was created on PLGA surfaces using polystyrene nanospheres (500, 200, or 100 nm) as templates.
• Inverse poly(dimethylsiloxane) molds were fabricated from the nanosphere templates.
• PLGA was cast using these molds to create surfaces with controlled nanostructure.

Main Results:

• Atomic Force Microscopy (AFM) revealed greater initial fibronectin spreading on PLGA with 200 nm spherical features compared to other formulations.
• PLGA surfaces with 200 nm spherical features significantly promoted vascular cell (endothelial and smooth muscle cell) adhesion compared to smooth PLGA or surfaces with 500/100 nm features.
• A specific nanometer surface feature size (200 nm) was identified as critical for promoting key cellular interactions.

Conclusions:

• This study demonstrates that precisely controlled 200 nm spherical nanostructures on PLGA surfaces enhance fibronectin spreading.
• These specific nanostructures effectively promote vascular cell adhesion, a crucial factor for improving small diameter vascular graft patency.
• The findings provide a targeted approach for designing next-generation vascular grafts with enhanced biocompatibility and performance.