FIGURE 2.
Cytotoxicity of single alpha solutions. The influence of 212Pb-TCMC-TP-3 or 212Pb-TCMC-rituximab (RTX) on OHS spheroid growth after 1 or 4 h treatment at (A) increasing 212Pb-activities and (B,C) over time. The normalized volume was calculated by dividing the volume of the treated spheroid by the volume of untreated spheroids (0 kBq/ml) at each time point. (C) Microscope images (4× magnification, scale bar = 500 μm) were taken from the day of treatment (day 0, 8.5 ± 0.5 × 106 μm3) to week 3. At the experimental end point (week 3), spheroids were stained with fluorescein diacetate and propidium iodide to observe live and dead cells, respectively. All spheroid images were taken by an inverted Axiovert 200M microscope (Carl Zeiss AG) and analyzed with the AxioVision Rel. 4.8 software (Carl Zeiss AG). Specific activities were 7.3–15.4 MBq/mg.