Imaging microglia in brain slices and slice cultures

Area of Science:

• Neuroscience
• Cell Biology
• Immunology

Background:

• Microglia (MG) are crucial immune cells in the central nervous system.
• Understanding MG behavior is vital for neurological research.
• Existing methods may limit real-time analysis of MG in native tissue environments.

Purpose of the Study:

• To develop and validate a method for imaging and analyzing microglial behavior in live rodent brain tissue slices.
• To enable real-time observation of microglial functions such as motility, migration, and phagocytosis.
• To provide a platform for dissecting the molecular mechanisms underlying microglial activity and testing potential therapeutic agents.

Main Methods:

• Utilizing multichannel confocal or two-photon time-lapse imaging of fluorescently labeled parenchymal microglia (MG).
• Applying the method to acutely prepared brain tissue slices from neonatal and adult rodents, as well as slice cultures.
• Employing bath application of reagents like ATP to induce spatial and temporal gradients for studying MG migration.

Main Results:

• Demonstrated real-time analysis of MG behaviors including motility, migration, chemotaxis, proliferation, and phagocytosis in live brain tissue.
• Confirmed applicability to various rodent models, including transgenic and green fluorescent protein reporter mice.
• Showcased the ability to induce MG migration using chemical gradients, facilitating studies on chemokinesis and chemotaxis.

Conclusions:

• The developed imaging method provides a powerful tool for studying microglia (MG) in semi-intact central nervous system preparations.
• This approach facilitates the dissection of the molecular basis of MG behaviors and the evaluation of candidate reagents.
• The technique is valuable for advancing our understanding of MG function in both development and disease states.