Inveon micropet microct hybrid scanner

B6 mice were injected iv or sc with 3–7 MBq of ⁶⁴Cu-labeled ALT-803 [12 (link),15 (link)]. Static PET scans were performed on anesthetized animals at various time-points after injection using an Inveon microPET/microCT hybrid scanner (Siemens). Data acquisition, image reconstruction, and region-of-interest analysis to calculate the percentage injected dose per gram of tissue (%ID/g) for major organs were conducted as previously described [12 (link),15 (link)].

Protein conjugation methods with 2-S-(4-isothiocyanatobenzyl)-1,4,7-triazacyclononane-1,4,7-triacetic acid (p-SCN-Bn-NOTA) (Macrocyclics), radiolabeling with ⁶⁴CuCl₂ (UW-Madison cyclotron facility), and subsequent purification were conducted as previously described (33 (link)). For serial PET imaging, C57BL/6 mice were injected intravenously (i.v.) with 3-7 MBq of ⁶⁴Cu-labeled ALT-803 or IL-15 (~3.7 GBq/mg protein). Static PET scans were performed on anesthetized animals at various times post-injection using an Inveon microPET/microCT hybrid scanner (Siemens). Data acquisition, image reconstruction, and region-of-interest analysis to calculate the percentage injected dose per gram of tissue (%ID/g) for major organs were conducted as previously described (33 (link), 34 (link)). At various times post-injection, mice were euthanized and blood, lymph nodes, thymus, and major organs/tissues were collected and weighed. The radioactivity in each tissue was measured using a gamma-counter (Perkin Elmer) and presented as %ID/g.