3D-Printed Submicron Patterns Reveal the Interrelation between Cell Adhesion, Cell Mechanics, and Osteogenesis

Area of Science:

• Biomaterials Science
• Cellular Mechanics
• Surface Engineering

Background:

• Surface topography is critical for implantable device integration.
• Quantitative data linking topography to cellular response cascades is limited.

Purpose of the Study:

• To systematically investigate the relationship between surface topography and cellular responses.
• To understand how 3D-printed submicron pillar dimensions and arrangements influence cell adhesion, cytoskeletal organization, and matrix mineralization.

Main Methods:

• Direct laser writing to fabricate 3D-printed submicron pillars with controlled dimensions.
• Single-cell force spectroscopy to measure cell adhesion forces and work of adhesion.
• Cell morphology, focal adhesion, and cytoskeletal organization analysis.
• Osteopontin expression analysis for matrix mineralization.

Main Results:

• Pillar height and density significantly influenced cell adhesion, focal adhesion formation, and cell settlement ('top state').
• Tall, dense pillars promoted enhanced actin stress fibers, higher elastic modulus, and organized cytoskeletal networks.
• Submicron pillar topography upregulated osteopontin expression, indicating enhanced matrix mineralization.

Conclusions:

• Surface topography, specifically tall and dense submicron pillars, can guide the cascade of cellular events from adhesion to matrix mineralization.
• These findings provide insights for designing instructive surfaces for medical devices using physical cues.