Research Article

Monitoring the Bystander Killing Effect of Human Multipotent Stem Cells for Treatment of Malignant Brain Tumors

Figure 7

Quantification of in vivo imaging data to monitor suicide gene therapy using hMultistem as cellular vehicles in the Hs683 oligodendroglioma model. (a) Quantification of the volume of hypointense voxels in animals receiving SPIO labeled hMultistem cells indicates sufficient contrast to detect the therapeutic cells in the Hs683 tumor model (sham (no cells): , PBS treated: , and GCV treated: ). (b) Bioluminescent imaging data showed that the stem cells were detectable through BLI, but no statistically significant difference in stem cell viability between the PBS and GCV receiving animals could be detected following treatment. However, there was a small decrease in the BLI signal before and after treatment in the GCV treated group. (c) Tumor volume measurements proved no statistical differences between sham operated, PBS treated, or GCV treated animals (green bar: hMultistem injection; red bar: duration of GCV/PBS treatment). (d) T1-weighted MRI pre- and postcontrast injection showed BBB integrity loss in the Hs683 tumor compared to the contralateral hemisphere and the extracranial muscle at all time points (). Levels of significance are expressed as , , , and .