Quantitative assessment of cell contractility using polarized light microscopy.

Area of Science:

• Cellular mechanics
• Biophysics
• Microscopy

Background:

• Cell contractility is crucial for biological processes, but measuring it in complex samples is difficult.
• Existing methods for measuring cell contractility have significant limitations.
• A need exists for a versatile and accessible method to quantify cell contractility.

Purpose of the Study:

• To develop and validate a novel method for measuring cell contractility.
• To demonstrate the utility of quantitative polarization microscopy for assessing cellular forces.
• To provide a straightforward and tractable approach for cell contractility measurements.

Main Methods:

• Quantitative polarization microscopy was employed to measure optical retardance.
• The relationship between optical retardance and cell contractility was investigated.
• The method was tested on 2D and 3D platforms, various cell types, and in situ mouse tumor tissues.

Main Results:

• Optical retardance signal is directly proportional to cell contractility.
• The method is effective in both 2D and 3D environments.
• Label-free contractility measurements were achieved in fixed and live cells, including those in tumor tissues.

Conclusions:

• Quantitative polarization microscopy provides a novel, flexible, and easily implementable method for assessing cell contractility.
• This technique overcomes limitations of current methods, enabling measurements in diverse biological systems.
• The method has significant potential to advance the field of cell mechanics.