Cell Structure Controls Endothelial Cell Migration under Fluid Shear Stress

Area of Science:

• Cell biology
• Biomechanics
• Biophysics

Background:

• Endothelial cells exhibit mechanotaxis, changing migration in response to shear stress.
• Cellular response to shear stress is altered on micropatterned substrates.
• The role of cytoskeletal structure versus adhesion area in micropatterned endothelial mechanotaxis is unclear.

Purpose of the Study:

• To investigate the mechanisms suppressing endothelial mechanotaxis on micropatterned substrates.
• To determine whether cytoskeletal structure or adhesion area limits mechanosensitivity in aligned endothelial cells.

Main Methods:

• Examined endothelial cells on wide (100-200 μm) micropatterned lines under shear stress.
• Assessed cell morphology and migration patterns in central and edge regions of micropatterned lines.
• Introduced scratch wounds perpendicular to micropatterns and observed cell migration.

Main Results:

• Cells in the center of micropatterned lines showed cobblestone morphology and triphasic mechanotaxis.
• Cells at the edges of micropatterned lines migrated parallel to the line axis, irrespective of flow direction.
• Elongated cells on upstream edges of sparsely populated lines initially migrated parallel to the edge before aligning with shear stress.

Conclusions:

• Cytoskeletal structure, not available adhesion area, is the primary determinant of endothelial mechanotaxis.
• Elongated cytoskeletal organization in micropatterned endothelial cells suppresses mechanosensitivity to shear stress.
• Endothelial cell migration behavior is context-dependent, influenced by substrate topography and cellular alignment.