Annafrancesca Rigato1 Felix Rico1

1, U1006 Inserm & Aix-Marseille Université, Marseilles, , France

The mechanical properties of living cells provide structural stability and mechanical flexibility, crucial for their function. Thus, molecular understanding of the mechanics of the cell is relevant to understand biological function. High-speed atomic force microscopy (HS-AFM) is a unique technology that combines nanometric-imaging capabilities at video rate (1). We have recently adapted a HS-AFM system to develop high-frequency microrheology to probe the viscoelastic response of living cells from 1 Hz to 100 kHz (2). We report the viscoelasticity of different cell types under cytoskeletal drug treatments. At high frequencies, cells exhibit rich viscoelastic responses that reflect the state of the cytoskeleton filaments. The comparison of benign and malignant cancer cells revealed remarkably different scaling laws at short timescales. Microrheology over a wide dynamic range provides mechanistic understanding of cell mechanics and a univocal fingerprint, applicable for diagnosis or prognosis of disease.

1. T. Ando et al., A high-speed atomic force microscope for studying biological macromolecules. Proceedings of the National Academy of Sciences 98, 12468 (2001).
2. A. Rigato, A. Miyagi, S. Scheuring, F. Rico, High-frequency microrheology reveals cytoskeleton dynamics in living cells. Nat Phys 13, 771 (2017).