Using a co-culture microsystem for cell migration under fluid shear stress

Area of Science:

• Biomedical Engineering
• Cell Biology
• Microfluidics

Background:

• Cell-cell interactions and migration are crucial in physiological processes and tissue repair.
• Understanding the influence of physical forces like shear stress on cell behavior is vital.
• Conventional co-culture methods face challenges in controlling gap size and observing cell dynamics.

Purpose of the Study:

• To develop and validate a microsystem for co-culturing endothelial cells (ECs) and smooth muscle cells (SMCs) with defined gap sizes.
• To quantitatively investigate the impact of varying gap sizes and fluid shear stress on cell migration.
• To explore the mutual influence of cell migration velocity and distance in a co-culture setting.

Main Methods:

• Utilized hydrostatic pressure for seeding ECs and SMCs across micro-gaps (50-500 μm).
• Applied controlled fluid shear stress (7 and 12 dyne cm⁻²) to co-cultures.
• Observed and analyzed cell migration patterns and velocities using the developed microsystem.

Main Results:

• Smaller gap sizes (50 μm and 100 μm) significantly promoted cell migration, suggesting paracrine signaling.
• Fluid shear stress inhibited cell migration onset in a dose-dependent manner, irrespective of gap size.
• The inhibitory effect of shear stress on cell migration was more pronounced at larger gap sizes (500 μm).

Conclusions:

• The developed co-culture microsystem effectively overcomes limitations of traditional methods for studying cell interactions.
• Gap size and fluid shear stress are critical modulators of EC and SMC migration.
• This technology holds potential for bio-manipulation and advancing tissue repair engineering strategies.