High-resolution imaging using a novel atomic force microscope and confocal laser scanning microscope hybrid...

Area of Science:

• Cell Biology
• Biophysics
• Microscopy

Background:

• Advances in 'omics' technologies necessitate tools for subcellular analysis.
• Understanding biomarker roles in pathogenicity requires detailed cellular investigation.

Purpose of the Study:

• To develop an efficient sample preparation method for coupled atomic force microscopy and confocal laser scanning microscopy (AFM-CLSM).
• To enable concurrent high-resolution structural and fluorescence imaging of nanoscale cellular components.
• To investigate the ultra-structure and molecular composition of filopodia.

Main Methods:

• Developed a novel sample preparation protocol using methanol-free formaldehyde fixation and quantum dot nanocrystal labeling.
• Applied coupled AFM-CLSM for multi-modal imaging of epithelial cell filopodia.
• Optimized protocols to maximize fluorescence and preserve ultra-structure.

Main Results:

• Achieved high-quality AFM-CLSM images, revealing a "quilted" surface structure of filopodia.
• Correlated AFM-detected apical cell surface ridges with punctate moesin clusters.
• Provided direct visualization of moesin linkages between transmembrane proteins and the cytoskeleton.

Conclusions:

• The novel AFM-CLSM technique offers unprecedented insights into cellular topography, molecular composition, and biophysical properties.
• This multi-modal imaging approach significantly enhances understanding of cellular structure-function relationships.
• The developed methodology is crucial for analyzing nanoscale features in cell biology.