Localized elasticity measured in epithelial cells migrating at a wound edge using atomic force microscopy

Area of Science:

• Cell Biology
• Biophysics
• Pulmonary Medicine

Background:

• Lung homeostasis relies on epithelial wound healing, involving cell spreading and migration.
• Cellular mechanical properties may guide epithelial cell migration during wound repair.

Purpose of the Study:

• To investigate variations in the stiffness of human bronchial epithelial cells (16HBE cells) near a scratch wound.
• To determine if RhoA signaling influences cell stiffness and migration cues.

Main Methods:

• Atomic Force Microscopy (AFM) was used to measure cell stiffness in human bronchial epithelial cells.
• Cells were analyzed at varying distances from a scratch wound edge.
• The role of RhoA was assessed using adenovirus-mediated expression of a dominant-negative form.

Main Results:

• Cell stiffness was significantly lower within 5 microm of the wound edge, peaking between 10-15 microm.
• Cells far from the wound edge (>2.75 mm) had lower median stiffness values (<5 kPa).
• Inhibition of RhoA reduced cell stiffness and abolished the stiffness peak near the wound edge.

Conclusions:

• Localized changes in cell stiffness near wound edges provide signals for epithelial cell migration.
• RhoA signaling plays a critical role in regulating cell stiffness and directing migration during lung epithelial wound healing.