Localized mechanical stimulation of single cells with engineered spatio-temporal profile

Area of Science:

• Cell Biology
• Biophysics
• Materials Science

Background:

• Cells in vivo experience diverse mechanical stimuli from their environment, influencing biological functions.
• Current in vitro methods struggle to replicate the complex spatio-temporal mechanical signals cells encounter.
• Understanding cellular responses to mechanical forces is crucial for various biological processes.

Purpose of the Study:

• To introduce a novel platform for studying cell-extracellular environment mechanical coupling.
• To enable in vitro replication of complex, dynamic mechanical stimuli on single cells.
• To investigate the impact of tunable mechanical forces on cellular behavior.

Main Methods:

• Developed an active cell culture substrate using iron-coated polymeric micropillars.
• Utilized quasi-static magnetic fields to control micropillar deflection and apply localized forces.
• Applied synchronous, tunable mechanical stimuli to specific cell membrane regions.
• Validated the platform using NIH3T3 fibroblasts subjected to periodic stimuli.

Main Results:

• Demonstrated the platform's ability to apply complex stress fields and localized forces with controlled intensity and temporal profiles.
• Observed that low-frequency mechanical stimulation impacts the actin cytoskeleton and nuclear morphology.
• Found that mechanical stimuli affect H2B core-histone dynamics and induce MKL transcription-cofactor translocation.

Conclusions:

• The new platform effectively replicates dynamic in vivo mechanical environments for cell studies.
• Mechanotransduction mechanisms can be investigated with high parallelism and tunable stimuli.
• This technology offers significant potential for advancing mechanobiology research in cells and tissues.