Figure 2.

MV-NIS promotes radioiodine uptake in infected medulloblastoma cells. Radionuclide uptake assays were performed with A. UW426 and B. D283med. Each cell line was infected with MV-NIS or MV-GFP (MOI of 0.1) and then exposed to 1 × 10⁵ cpm of ¹²⁵I at 24, 48 or 72 hours post infection. Due to excessive cell death at 72 hours, only data from the 24 and 48 hour timepoints are shown. The addition of KClO₄ to the cells effectively blocked incorporation of ¹²⁵I. Each sample was run in triplicate, with error bars representing one standard deviation. +/− denotes the presence or absence of KClO₄ respectively. C. Radioiodine kinetics in UW426 and D283med 48 hours after MV-NIS infection. Efflux of ¹²⁵I is rapid, with a t_1/2 retention time of approximately 1.5 minutes for each cell line. Data points are the average of four independent samples. D. Medulloblastoma xenografts incorporate ¹³¹I following MV-NIS infection. The mouse in the left panels received a 2 × 10⁵ TCID₅₀ intratumoral injection of MV-NIS three days following tumor implantation whereas the mouse in the right panels was given an equal volume of OptiMEM to serve as a vehicle control. Tumor bioluminescence was visualized 48 hours later, and the mice were subsequently given an IP injection of 37 MBq ¹³¹I. Cherenkov luminescence from the irradiated tumors was then visualized the following day.