Immortalization and characterization of rat microglial cells

Area of Science:

• Neuroscience
• Cell Biology
• Immunology

Background:

• Microglia are crucial immune cells of the central nervous system.
• Establishing stable microglial cell lines is essential for studying their functions.
• Previous methods for microglial culture have limitations in long-term study.

Purpose of the Study:

• To develop immortalized rat microglial cell lines for research.
• To characterize the phenotype and function of these novel cell lines.
• To assess the stability of microglial properties in long-term culture.

Main Methods:

• Rat microglial cells were infected with a retrovirus carrying a temperature-sensitive simian virus 40 large T antigen.
• Cells were cultured in the presence of neomycin and granulocyte-macrophage colony-stimulating factor (GM-CSF).
• Phenotypic characterization included immunoreactivity assays and phagocytosis tests at different temperatures.

Main Results:

• Immortalized microglial cell lines were successfully established and proliferated at 33°C.
• At 39°C (non-functional T antigen), cells displayed a distinct microglial phenotype and phagocytic activity.
• Cell surface antigen expression decreased after 15 passages, but could be partially restored by specific cytokines.

Conclusions:

• The simian virus 40 large T antigen is effective for immortalizing rat microglial cell lines.
• These cell lines retain key microglial characteristics and functions, making them valuable research tools.
• Long-term culture stability and potential modulation of microglial properties were demonstrated.