Comparison of multiplexed mAb imaging with bioluminescence. (A) NSG mice (n = 6) previously injected intravenously with 5 × 106 MOLM-13luc cells were imaged for fluorescence and bioluminescence after 4 and 5 weeks. Images were acquired on the same day 24 hours after mAb injection (CD13/45/HLA ABC, total 1 μg/g, 0.33 μg/g of each antibody) and 10 minutes after luciferin administration (150 mg/kg IP). Images depict the maximum to minimum fluorescence/bioluminescence for each mouse. Bioluminescence images on weeks 4 and 5 are shown with both log and linear scaling to permit optimal visualization of leukemic infiltrates. (B) A very good correlation with Pearson correlation coefficient = 0.80 was noted between total bioluminescence and the fold increase in fluorescence. (C) All leukemic infiltrates were confirmed histologically. EP indicates epiphyseal plate; LBM, leukemic bone marrow; LC, leukemic cells; NBM, normal bone marrow; and PC, photon counts.