Equibiaxial Stretching Device for High Magnification Live-Cell Confocal Fluorescence Microscopy.

Area of Science:

• Mechanobiology
• Cellular mechanics
• Biomedical engineering

Background:

• Cells experience mechanical forces in physiological and pathological states.
• Understanding cellular responses to mechanical stress is crucial for tissue engineering and disease research.
• Existing tools for in vitro mechanical stress application have limitations.

Purpose of the Study:

• To design, fabricate, and characterize a versatile stretching device for in vitro mechanobiology studies.
• To enable high-resolution live-imaging of cells under controlled mechanical loading.
• To provide a platform for investigating cellular responses to tensile and compressive stresses.

Main Methods:

• A vacuum-actuated polydimethylsiloxane (PDMS) membrane system for equibiaxial stretching.
• Integration with high-resolution optical and fluorescence microscopy.
• Methods for applying controlled tensile and compressive stresses, including cyclic loading.
• Substrate modification for cell adhesion, topographical patterning, and stiffness variation using polyacrylamide gels.

Main Results:

• The device produces homogeneous, reproducible, and controlled sample strain.
• It accommodates various stretching protocols, from immediate to cyclic stretch-release.
• Live-cell imaging under mechanical stress is feasible with fluorescent reporters.
• The system allows multimodal imaging (fluorescence and electron microscopy) and substrate stiffness modulation.

Conclusions:

• The developed stretching device is a valuable tool for mechanobiology research.
• It facilitates the study of cellular responses to diverse mechanical stimuli in vitro.
• This system supports a wide range of investigations into cell-material interactions and mechanotransduction.