Combination of flow and micropattern alignment affecting flow-resistant endothelial cell adhesion

Area of Science:

• Biomaterials Science
• Cell Biology
• Biomedical Engineering

Background:

• Endothelial cell (EC) adhesion to biomaterials is critical for vascular graft success.
• In vivo, ECs experience both surface topography and mechanical forces from blood flow.
• Previous studies often overlooked the combined effects of topography and flow on EC adhesion.

Purpose of the Study:

• To investigate how biomaterial surface topography and blood flow interact to influence EC adhesion.
• To determine the optimal alignment of surface micropatterns relative to flow for enhanced EC adhesion.

Main Methods:

• Cultured human umbilical vein endothelial cells (HUVECs) on fibronectin (FN) micropatterns.
• Exposed cells to physiological shear stress (15 dyne/cm²) under sustained flow.
• Utilized experimental and numeric modeling to analyze cell adhesion and mechanical responses.

Main Results:

• Micropattern alignment parallel to flow direction significantly enhanced flow-resistant EC adhesion.
• Perpendicular alignment of micropatterns attenuated EC adhesion.
• Flow-induced pressure on cells played a more critical role than shear stress in EC adhesion.

Conclusions:

• Integrating topographical cues with flow conditions is essential for improving EC adhesion.
• Parallel alignment of surface micropatterns with flow offers a promising strategy for vascular graft design.
• Findings suggest new approaches for developing functional vascular grafts with enhanced cell integration.