STED/AFM as a tool to investigate mechanical and adhesive properties of migrating keratinocytes

E-cadherin is a key component of adherens junctions which maintains epithelial integrity. In keratinocytes, wound healing requires dynamic modulation of adhesion and cytoskeletal organization. Using a wound healing assay combined with stimulated emission depletion/atomic force microscopy (STED/AFM), we analysed E-cadherin binding during murine keratinocyte migration. Wound closure occurred within 6 h and was accompanied by E-cadherin accumulation at the leading edge. Transient expression of E-Cadherin-SNAP enabled investigation of E-cadherin interactions. Inhibition of actin polymerization abolished E-cadherin binding and reduced cellular stiffness. Imaging of SiR-actin-labeled cells enabled simultaneous visualization of migration and measurement of binding and mechanical properties. E-cadherin retained functional binding properties during migration. These findings establish STED/AFM as a powerful method to investigate single-molecule binding properties in migrating cells.