Figure 6: In vitro and in vivo bioluminescence imaging (BLI) of the hNSCs. (a) In vitro  imaging analysis of genetically engineered hNSCs shows increasing fluc activity with cell density and a linear correlation ( ). (b) Data are representative of three independent experiments performed in triplicate. Representative BLI of stroke-lesioned rats transplanted with the hNSCs and monitored for (c) 4 weeks and (d) 8 weeks posttransplantation survival times. Quantitative analysis of the fluc activity in these animals shows a stable BLI signal, which suggests the survival of the grafts and the nonproliferative property of the hNSCs. Color scale bar is in photon/s/cm2/sr.