Phenotypic changes in NG2+ cells after spinal cord injury

Area of Science:

• Neuroscience
• Cell Biology
• Regenerative Medicine

Background:

• Spinal cord injury (SCI) leads to rapid oligodendrocyte loss.
• NG2-expressing cells proliferate post-SCI and may replenish lost oligodendrocytes and astrocytes.
• Understanding adult NG2(+) cell characteristics is crucial for SCI repair strategies.

Purpose of the Study:

• To compare NG2(+) cells from adult injured spinal cords with those from uninjured adult and early postnatal cords.
• To investigate the antigenic and physiological properties of NG2(+) cells after SCI.
• To assess the potential of NG2(+) cells to differentiate into mature oligodendrocytes post-injury.

Main Methods:

• Isolation and dissociation of NG2(+) cells from adult injured and uninjured, and early postnatal spinal cords.
• Immunocytochemistry for NG2, nestin, A2B5, O4, and O1 markers.
• Patch clamp analysis to evaluate voltage-gated potassium currents.
• Assessment of cellular response to GABA and glutamate.

Main Results:

• More NG2(+) cells were isolated from injured cords, but microglia/macrophages predominated.
• Adult NG2(+) cells showed distinct antigenic profiles (NG2+/A2B5-) compared to postnatal cells (NG2-/A2B5+).
• NG2(+) cells from injured adults exhibited altered potassium currents and reduced responsiveness to GABA/glutamate versus postnatal cells.

Conclusions:

• Adult NG2(+) cells are antigenically and physiologically distinct from early postnatal NG2(+) cells.
• Contusive SCI induces significant changes in adult NG2(+) cell properties.
• These alterations may affect the capacity of NG2(+) cells to contribute to spinal cord repair after injury.