Atomic force microscopy imaging of live mammalian cells

Area of Science:

• Cell Biology
• Biophysics
• Microscopy

Background:

• Understanding cell locomotion is crucial for various biological processes.
• Live cell imaging presents challenges in maintaining cell viability and immobilization.
• Atomic force microscopy (AFM) offers high-resolution imaging of cellular structures.

Purpose of the Study:

• To investigate the morphology and locomotion dynamics of live mammalian adherent and suspended cells using AFM.
• To characterize the cytoskeletal rearrangements during cell movement.
• To develop and evaluate effective immobilization strategies for suspended cells.

Main Methods:

• Utilized time-lapse Atomic Force Microscopy (AFM) to observe live cell dynamics.
• Examined MCF-7 (adherent) and Neuro-2a (elongated) cell lines.
• Developed a novel immobilization method for suspended cells using polydimethylsiloxane (PDMS) wells and poly-L-lysine (PLL) adsorption.

Main Results:

• Observed formation and reorganization of sawtooth-like filopodia during MCF-7 cell retraction.
• Documented increased lamellipodium thickness during MCF-7 cell retraction.
• Revealed cytoskeleton reorganization from irregular to parallel morphology in elongated Neuro-2a cells.
• Successfully imaged the morphology of a single live lymphoma cell using the developed immobilization technique.

Conclusions:

• AFM provides valuable insights into the dynamic morphological changes during cell locomotion.
• The observed cytoskeletal dynamics are key to understanding cell movement.
• The combined PDMS well and PLL adsorption method is effective for immobilizing suspended cells for AFM imaging.
• This research contributes to a better understanding of cell locomotion and offers improved cell immobilization strategies.