Images show synthesis of immuno-PET antibody composed of native daratumumab labeled with positron-emitting radionuclide zirconium 89 (89Zr) through chelator deferoxamine (DFO), or 89Zr-DFO-daratumumab, and evaluation in murine model of multiple myeloma. (a) Schematic representation illustrates conjugation of DFO chelator to daratumumab with subsequent labeling with 89Zr (not to scale). (b) Bioluminescent imaging of OPM2-injected (top) and healthy (bottom) mice demonstrates location of cancer cells in disease model (left, prone; right, supine). Bioluminescence images were taken no more than 24 hours before administration of radiotracer. (c) PET/CT images of OPM2-injected and healthy mice 144 hours after injection of 89Zr-DFO-daratumumab. OPM2 mice exhibit higher level of tracer uptake than do healthy mice. Uptake pattern of 89Zr-DFO-daratumumab matches pattern of cancer localization as seen in bioluminescence images. MIP = maximum intensity projection. White arrows indicate knees, green arrows indicate lumbar spine, and yellow arrows indicate pelvis. Dotted line on coronal images defines plane of trans-axial images. (d) Biodistribution of 89Zr-DFO-daratumumab at 144 hours after injection. %ID/g = percent injected dose per gram. LI = large intestine, SI = small intestine.