Super-resolution Analysis of Astrocyte Morphology Using Expansion Microscopy.

Area of Science:

• Neuroscience
• Cell Biology
• Microscopy

Background:

• Astrocyte morphology is crucial for cellular functions, signal propagation, and intercellular communication within the brain.
• Diffraction-limited microscopy struggles to resolve fine astrocytic processes, hindering detailed structural analysis.
• Electron microscopy provides high resolution but is complex; expansion microscopy (ExM) offers an accessible alternative.

Purpose of the Study:

• To present a comprehensive protocol for visualizing astrocytes and their associated structures using expansion microscopy.
• To detail the localization of synaptic and astrocytic proteins within the fixed brain tissue.
• To overcome the limitations of conventional microscopy in resolving fine astrocytic processes.

Main Methods:

• Utilizing expansion microscopy (ExM) to physically expand fixed brain tissue.
• Preserving the relative spatial positioning of fluorescent labels marking cellular structures and proteins.
• Employing confocal fluorescence microscopy for imaging the expanded samples.

Main Results:

• Successfully visualized fine astrocytic processes and their perisynaptic arrangements with enhanced resolution.
• Enabled detailed localization of synaptic structures and key astrocytic and synaptic proteins.
• Demonstrated the efficacy of ExM for detailed astrocyte structural analysis.

Conclusions:

• Expansion microscopy provides a cost-effective and accessible method for high-resolution imaging of astrocytes.
• This protocol facilitates a deeper understanding of astrocyte morphology and its role in brain function.
• ExM is a valuable tool for studying astrocyte-synapse interactions and cellular architecture.