Microparticle traction force microscopy reveals subcellular force exertion patterns in immune cell-target...

Area of Science:

• Cellular Mechanics
• Biophysics
• Microscopy Techniques

Background:

• Cellular force exertion is critical for biological processes.
• Traditional traction force microscopy (TFM) is limited by planar geometry.
• A need exists for 3D force sensing in cellular studies.

Purpose of the Study:

• To develop a particle-based force sensing strategy for studying cellular interactions in three dimensions.
• To overcome the geometric limitations of classical TFM.
• To enable high-sensitivity inference of traction forces from particle shape.

Main Methods:

• Synthesized uniform, deformable, and tuneable hydrogel particles via a batch approach.
• Resolved 3D particle shape with super-resolution accuracy (<50 nm) using confocal microscopy.
• Developed a reference-free computational method for inferring traction forces directly from particle deformation.

Main Results:

• Demonstrated the ability to resolve subcellular force patterns during phagocytic engulfment.
• Revealed force dynamics within the cytotoxic T-cell immunological synapse.
• Validated a sensitive, 3D particle-based approach for cellular force measurement.

Conclusions:

• The developed particle-based strategy offers a versatile tool for studying cellular forces in 3D.
• This method overcomes the limitations of planar TFM, enabling broader applications.
• The approach provides high-resolution insights into cell mechanics and cell-cell interactions.