PET Imaging of 64Cu-Labeled LDH-BSA in 4T1 Tumors

Serial PET scans of ⁶⁴Cu-LDH-BSA were performed in 4T1 tumor-bearing mice (n = 3) using a microPET/microCT Inveon rodent model scanner (Siemens Medical Solutions USA, Inc.), at different time points (0.5 h, 3 h, 16 h , and 24 h) post-injection (p.i.) of ⁶⁴Cu-LDH-BSA via tail vein. Data acquisition, image reconstruction, and region-of-interest (ROI) analysis of the PET data were performed as previously described13 (link)42 (link)43 (link). Quantitative data of ROI analysis on tumor and other organs were presented as percentage injected dose per gram of tissue (%ID/g). To validate the labeling and imaging of ⁶⁴Cu-LDH-BSA, ⁶⁴Cu-BSA was also scanned in 4T1 tumor-bearing mice (n = 3) as a control group. After the last scan at 24 h p.i., mice were sacrificed under anesthesia for biodistribution studies. Tumor, blood and major organs/tissues were collected and weighted. The radioactivity in the tissue was measured using a γ counter (PerkinElmer) and presented as %ID/g (mean ± SD).