(127b) Membrane Capacitance As a Label-Free Marker of Neural Stem Cell Fate

Understanding the factors regulating cell fate in the neural lineage is key for optimizing the use of neural stem and progenitor cells (NSPCs) for repair of the brain and spinal cord. However, little is known regarding the specific cell biological properties of neuron and astrocyte progenitors (NPs and APs) in this lineage.  We found whole cell plasma membrane capacitance measured by dielectrophoresis is sufficient to distinguish and prospectively isolate NPs and APs from heterogeneous NSPCs without the use of labels.

These specific properties tied to cell fate may indicate the presence of cell membrane molecules involved in directing progenitors along neuronal or astrocytic fates. We hypothesized cell surface carbohydrates may contribute to fate-specific membrane capacitance. N-glycosylation controls cell surface expression and ligand binding of multiple classes of receptors affecting cell fate, and thus could regulate how cells respond to environmental cues. 

We analyzed glycosylation enzymes by qRT-PCR and quantitated cell surface N-glycans by lectin binding and MALDI-TOF and found differences in glycosylation patterns between NPs and APs. Treatment of cells with specific agents to modify glycosylation pathways led to shifts in membrane capacitance. Furthermore, alteration of the glycosylation patterns on the cell surface was sufficient to change cell fate. Accurate patterns of glycosylation are critical for neural development in humans and rodents, highlighting the importance of glycosylation to NPs and APs in vivo. Our data indicate clear links among cell surface glycosylation, membrane capacitance, and cell fate, suggesting N-glycosylation is a critical regulator of cell fate in the neural lineage.