TY - JOUR T1 - In Vivo Labeling of Serum Albumin for PET JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 1150 LP - 1156 DO - 10.2967/jnumed.114.139642 VL - 55 IS - 7 AU - Gang Niu AU - Lixin Lang AU - Dale O. Kiesewetter AU - Ying Ma AU - Zhongchan Sun AU - Ning Guo AU - Jinxia Guo AU - Chenxi Wu AU - Xiaoyuan Chen Y1 - 2014/07/01 UR - http://jnm.snmjournals.org/content/55/7/1150.abstract N2 - The purpose of this study was to develop a novel in vivo albumin-labeling method to allow PET of cardiac function after myocardial infarction and vascular leakage and increased permeability in inflammatory diseases and malignant tumors. Methods: To label albumin in vivo, we synthesized a NOTA (1,4,7-triazacyclononane-N,N′,N″-triacetic acid)-conjugated truncated form of Evans blue (NEB). 18F labeling was achieved by the formation of an 18F-aluminum fluoride (18F-AlF) complex, and 64Cu labeling was obtained by a standard chelation method. Sixty-minute dynamic PET imaging was performed on normal mice to evaluate the distribution of 18F-AlF-NEB, which was compared with in vitro–labeled mouse serum albumin (18F-fluorobenzyl-MSA). Electrocardiography-gated PET imaging was performed in a mouse model of myocardial infarction. Both dynamic and static PET scans were obtained in a mouse inflammation model induced by local injection of turpentine to evaluate vascular leakage. Tumor permeability was studied by dynamic and late-point static PET using 64Cu-NEB in a UM-22B xenograft model. Results: NEB was successfully synthesized, and 18F labeling including work-up took about 20–30 min, with a radiochemical purity greater than 95% without the need for high-performance liquid chromatography purification. Most of the radioactivity was retained in the circulation system at 60 min after injection (26.35 ± 1.52 percentage injected dose per gram [%ID/g]). With electrocardiography-gated PET, ventricles of the heart and major arteries were clearly visualized. The myocardial infarction mice showed much lower left ventricular ejection fraction than the control mice. Inflammatory muscles showed significantly higher tracer accumulation than the contralateral healthy ones. UM-22B tumor uptake of 64Cu-NEB gradually increased with time (5.73 ± 1.11 %ID/g at 1 h and 8.03 ± 0.77 %ID/g at 2 h after injection). Conclusion: The distribution and local accumulation of serum albumin can be noninvasively visualized and quantified by 18F-AlF-NEB and 64Cu-NEB PET. The simple labeling and broad applications make these imaging probes attractive for clinical translation. ER -