A Simple Method to Test Mechanical Strain on Epithelial Cell Monolayers Using a 3D-Printed Stretcher.

Area of Science:

• Biophysics
• Cell Biology
• Biomaterials Engineering

Background:

• Mechanical forces significantly influence biological processes and disease.
• Existing in vitro mechanical strain devices are often expensive and lack specific applications for extracellular matrix (ECM)-driven strain on epithelial cells and cell-cell adhesion.
• There is a need for accessible and specialized equipment to study mechanotransduction.

Purpose of the Study:

• To introduce a novel, cost-efficient, and user-friendly 3D-printed stretching device for in vitro mechanical strain experiments.
• To evaluate the reliability and strain distribution of the developed device.
• To investigate the effects of mechanical strain on cell-cell adhesion in epithelial cell monolayers.

Main Methods:

• Development of a 3D-printed stretching device.
• Evaluation of strain distribution using speckle-tracking at 2.5% and 5% strains.
• Application of the device to Caco2 colon epithelial cell monolayers to assess effects on cell-cell adhesion.
• Immunofluorescence staining to quantify E-cadherin localization at cell-cell contacts and in the cytoplasm.

Main Results:

• The 3D-printed device demonstrated homogeneous strain distribution at 2.5% and 5% strains, confirming its reliability.
• Mechanical strain induced a significant reduction in E-cadherin at cell-cell contact sites in Caco2 cell monolayers.
• Increased translocation of E-cadherin to the cytoplasm was observed under mechanical strain, indicating impaired cell-cell adhesion.

Conclusions:

• A new, cost-effective, and reliable 3D-printed device for applying mechanical strain to cultured cells has been developed.
• The device effectively assesses the impact of mechanical strain on epithelial cell monolayers and cell-cell adhesion.
• Results confirm that increased extracellular matrix-driven strain negatively affects cell-cell adhesion by altering E-cadherin localization.