Drug-Induced Changes of Topography and Elasticity in Living B Lymphoma Cells Based on Atomic Force Microscopy

Atomic force microscopy (AFM) provides a means for characterizing the surface topography and biophysical properties of individual living cells under near-physiological conditions. However, owing to the lack of adequate cellular immobilization methods, AFM imaging of living, suspended mammalian cells is still a big challenge. In this paper, a method is presented for immobilizing individual living B lymphoma cells that combines mechanical trapping with pillar arrays and electrostatic adsorption with poly-L-lysine. In this way, the topography and elasticity changes of individual B lymphoma cells that were stimulated with different concentrations of Rituximab were observed and measured dynamically. When the cell is stimulated by 0.2 mg . mL(-1) Rituximab for 2 h, the cell topography becomes more corrugated and Young's modulus decreases from 196 to 183 kPa. When the cell is stimulated by 0.5 mg . mL(-1) Rituximab for 2 h, the cell topography changes more significantly and some tubercles appear, and Young's modulus decreases from 234 to 175 kPa. These results thus provide a unique insight into the effects of Rituximab on individual cells.