Extracellular Vesicles from Human Teeth Stem Cells Trigger ATP Release and Promote Migration of Human Microglia...

Area of Science:

• Neuroscience
• Cell Biology
• Immunology

Background:

• Extracellular vesicles (EVs) show promise in suppressing neuroinflammation and offering neuroprotection.
• The precise mechanisms by which EVs modulate microglial neuroinflammatory responses are not fully understood.

Purpose of the Study:

• To investigate the molecular mechanisms underlying the effects of stem cell-derived extracellular vesicles (SHED-EVs) on human microglial cell function.
• To elucidate the role of purinergic receptors and specific protein interactions in EV-mediated microglial responses.

Main Methods:

• Treatment of immortalized human microglial cells with SHED-EVs.
• Measurement of intracellular calcium (Ca2+) and adenosine triphosphate (ATP) release.
• Boyden chamber assays for cell migration.
• Pharmacological inhibition of purinergic receptors (e.g., P2X4R) and integrins (αVβ3/αVβ5).
• Proximity ligation and co-immunoprecipitation assays to assess protein interactions (MFG-E8 and P2X4R).

Main Results:

• SHED-EVs rapidly increased intracellular Ca2+ and ATP release in microglial cells.
• EVs significantly enhanced microglial migration by 20%, primarily through the P2X4 receptor (P2X4R) pathway.
• EVs promoted an association between milk fat globule-epidermal growth factor-factor VIII (MFG-E8) and P2X4R.
• Inhibition of αVβ3/αVβ5 integrin blocked EV-induced microglial migration and lipid raft formation.

Conclusions:

• Extracellular vesicles promote microglial motility via P2X4R/MFG-E8-dependent pathways.
• These findings reveal novel molecular mechanisms of EV interaction with microglia.
• This research provides potential therapeutic strategies for targeting neuroinflammation.