Figure 4.

Trypan blue cell exclusion assay results reveal no significant increase in hNPC death after 24 hour exposure to 100 μM MnCl₂, a concentration on the order of that expected in the brain after systemic MnCl₂ delivery. At this concentration, consistent results are observed for hNPC-WT and hNPC-DMT1. Cell death is observed at 0 μM due to the potentially toxic effects of the transfection solution and procedure on cells. The positive control dose of 1000 μM resulted in a significant increase in cell death for both cell types as well as a significant increase of hNPC-DMT1 death compared to hNPC-WT. #: p<0.05 compared to corresponding cell type supplemented with 0 μM MnCl₂; *: p<0.05 compared to hNPC-WT supplemented with same dose.