Microglia in Human Postmortem Brain Samples: Quantitative Ultrastructural Analysis of Scanning Electron Microscopy...

Area of Science:

• Neuroscience
• Cell Biology
• Microscopy

Background:

• Microglial cells are crucial for brain health and disease.
• Understanding microglial ultrastructure is vital for neurological research.
• Existing methods for postmortem brain tissue analysis have limitations.

Purpose of the Study:

• To provide a detailed protocol for preparing human postmortem brain samples for ultrastructural microglial analysis.
• To optimize sample quality for high-resolution imaging of microglia.
• To enable detailed examination of microglial morphology and function.

Main Methods:

• Aldehyde fixation and immunoperoxidase staining for myeloid cell marker (AIF1/IBA1) and phagolysosomal activity marker (CD68).
• Osmium-thiocarbohydrazide-osmium (OTO) post-fixation for enhanced membrane contrast.
• Scanning electron microscopy (SEM) for imaging microglial cell bodies.

Main Results:

• The protocol yields high-quality ultrastructural preservation of human postmortem brain samples.
• Immunostaining effectively labels microglial cells and their phagolysosomal activity.
• OTO fixation significantly improves cellular membrane visualization.
• SEM imaging allows detailed analysis of microglial cytoplasmic organelles and interactions.

Conclusions:

• This protocol offers a robust method for ultrastructural microglial analysis in human postmortem brain tissue.
• The described techniques facilitate detailed investigation of microglial morphology, organelle function, and cellular interactions.
• This approach will advance research into neurological disorders by providing deeper insights into microglial behavior.