BV2 Microglial Cell Activation/Polarization Is Influenced by Extracellular Vesicles Released from Mutated SOD1 NSC-34...

Area of Science:

• Neuroscience
• Cell Biology
• Immunology

Background:

• Microglia-mediated neuroinflammation is crucial in amyotrophic lateral sclerosis (ALS) pathogenesis.
• Neuroinflammation contributes to motor neuron (MN) degeneration in ALS.

Purpose of the Study:

• Investigate the role of extracellular vesicles (EVs) from mSOD1 NSC-34 MN-like cells in activating BV2 microglial cells.
• Determine the impact of small (<200 nm) and large (>200 nm) EVs on microglial inflammatory responses.

Main Methods:

• Isolated small and large EVs from NSC-34 cell culture medium via differential ultracentrifugation.
• Incubated BV2 cells with EV fractions for 12, 24, and 48 hours.
• Analyzed microglial inflammation (IL-1β, IL-6, IL-4, IL-10), inflammasome activation (IL-1β, caspase 1), cell death (caspase 3), glial recruitment (CXCR1), and TGFβ-R2 expression.

Main Results:

• mSOD1 EVs induced BV2 cell polarization towards an early neurotoxic and late neuroprotective phenotype.
• Observed mixed M1 and M2 microglia subpopulations.
• Identified the TGFβ/CX3CR1 axis as significant in driving microglial activation.

Conclusions:

• mSOD1-derived EVs modulate microglial polarization, influencing neuroinflammation in ALS.
• Targeting dysregulated microglial responses and neuroinflammation presents a promising therapeutic avenue for ALS.