Microglia Morphological Response to Mesenchymal Stromal Cell Extracellular Vesicles Demonstrates EV Therapeutic...

Area of Science:

• Neuroscience
• Immunology
• Cell Biology

Background:

• Mesenchymal stromal cell derived extracellular vesicles (MSC-EVs) show therapeutic potential for neuroinflammation.
• Microglia, the brain's immune cells, undergo phenotypic changes in response to inflammation, but their interaction with MSC-EVs is not fully understood.
• A lack of disease-relevant screening tools hinders the clinical translation of MSC-EVs.

Purpose of the Study:

• To develop a quantitative, high-throughput morphological profiling approach to assess microglial responses to neuroinflammation.
• To determine if microglial morphological changes can indicate the bioactivity of MSC-EVs.

Main Methods:

• Utilized an immortalized human microglia cell-line.
• Stimulated microglia with interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α).
• Assessed morphological changes using quantitative profiling and analyzed cytokine secretion, proteomic profiles, and mitochondrial morphology after MSC-EV treatment.

Main Results:

• MSC-EV treatment shifted microglial morphology towards an unstimulated state, indicating bioactivity.
• MSC-EVs altered the secretion of numerous chemokines and cytokines and significantly changed the cellular proteome.
• Observed modulation of immune response pathways and microglia mitochondrial morphology, suggesting effects on metabolism.

Conclusions:

• The study demonstrates MSC-EVs' comprehensive effects on microglial morphology, secretion, proteome, and mitochondria.
• A high-throughput morphological approach enables efficient screening of MSC-EV batches and manufacturing conditions.
• This adaptable method can enhance EV function and mitigate heterogeneity for therapeutic applications.