title: Imaging of genetically engineered T cells by PET using gold nanoparticles complexed to Copper-64.
abstract: Adoptive transfer of primary T cells genetically modified to have desired specificity can exert an anti-tumor response in some patients. To improve our understanding of their therapeutic potential we have developed a clinically-appealing approach to reveal their in vivo biodistribution using nanoparticles that serve as a radiotracer for imaging by positron emission tomography (PET). T cells electroporated with DNA plasmids from the Sleeping Beauty transposon-transposase system to co-express a chimeric antigen receptor (CAR) specific for CD19 and Firefly luciferase (ffLuc) were propagated on CD19(+) K562-derived artificial antigen presenting cells. The approach to generating our clinical-grade CAR(+) T cells was adapted for electro-transfer of gold nanoparticles (GNPs) functionalized with (64)Cu(2+) using the macrocyclic chelator (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid, DOTA) and polyethyleneglycol (GNP-(64)Cu/PEG2000). MicroPET/CT was used to visualize CAR(+)EGFPffLucHyTK(+)GNP-(64)Cu/PEG2000(+) T cells and correlated with bioluminescence imaging. These data demonstrate that GNPs conjugated with (64)Cu(2+) can be prepared as a radiotracer for PET and used to image T cells using an approach that has translational implications.
authors.affiliation: Baylor College of Medicine & Texas Children's Hospital, Department of Obstetrics & Gynecology, Division of Maternal Fetal Medicine, Houston, TX 77030, USA.
authors.forename: Parijat
authors.initials: P
authors.lastname: Bhatnagar
authors.forename: Zheng
authors.initials: Z
authors.lastname: Li
authors.forename: Yoonsu
authors.initials: Y
authors.lastname: Choi
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Guo
authors.forename: Feng
authors.initials: F
authors.lastname: Li
authors.forename: Daniel Y
authors.initials: DY
authors.lastname: Lee
authors.forename: Matthew
authors.initials: M
authors.lastname: Figliola
authors.forename: Helen
authors.initials: H
authors.lastname: Huls
authors.forename: Dean A
authors.initials: DA
authors.lastname: Lee
authors.forename: Tomasz
authors.initials: T
authors.lastname: Zal
authors.forename: King C
authors.initials: KC
authors.lastname: Li
authors.forename: Laurence J N
authors.initials: LJ
authors.lastname: Cooper
mesh_terms: D000818:Animals; D058948:Cell Tracking / Q000379:methods*; D003301:Copper Radioisotopes; D005818:Genetic Engineering / Q000379:methods; D006046:Gold; D053768:Metal Nanoparticles; D051379:Mice; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D013601:T-Lymphocytes / Q000000981:diagnostic imaging* / Q000502:physiology*
chemical_list: D003301:Copper Radioisotopes; D019275:Radiopharmaceuticals; D006046:Gold