Monitoring the Efficacy of Adoptively Transferred Prostate Cancer–Targeted Human T Lymphocytes with PET and Bioluminescence Imaging

Abstract

Noninvasive imaging technologies have the potential to enhance the monitoring and improvement of adoptive therapy with tumortargeted T lymphocytes. We established an imaging methodology for the assessment of spatial and temporal distributions of adoptively transferred genetically modified human T cells in vivo for treatment monitoring and prediction of tumor response in a systemic prostate cancer model. Methods: RM1 murine prostate carcinoma tumors transduced with human prostatespecific membrane antigen (hPSMA) and a Renilla luciferase reporter gene were established in SCID/beige mice. Human T lymphocytes were transduced with chimeric antigen receptors (CAR) specific for either hPSMA or human carcinoembryonic antigen (hCEA) and with a fusion reporter gene for herpes simplex virus type 1 thymidine kinase (HSV1tk) and green fluorescent protein, with or without click beetle red luciferase. The localization of adoptively transferred T cells in tumor-bearing mice was monitored with 29-18 F-fluoro-29-deoxy-1-b-D-arabinofuranosyl-5-ethyluracil ( 18 F-FEAU) small-animal PET and bioluminescence imaging (BLI). Results: Cotransduction of CAR-expressing T cells with the reporter gene did not affect CAR-mediated cytotoxicity. BLI of Renilla and click beetle red luciferase expression enabled concurrent imaging of adoptively transferred T cells and systemic tumors in the same animal. hPSMA-specific T lymphocytes persisted longer than control hCEA-targeted T cells in lung hPSMA-positive tumors, as indicated by both PET and BLI. Precise quantification of T-cell distributions at tumor sites by PET revealed that delayed tumor progression was positively correlated with the levels of 18 F-FEAU accumulation in tumor foci in treated animals. Conclusion: Quantitative noninvasive monitoring of genetically engineered human T lymphocytes by PET provides spatial and temporal information on T-cell trafficking and persistence. PET may be useful for predicting tumor response and for guiding adoptive T-cell therapy.

Biopolymers codelivering engineered T cells and STING agonists can eliminate heterogeneous tumors

“…Viable cells were isolated using Histopaque 1083 (Sigma-Aldrich) and expanded for 2 days without G418 before adoptive transfer. For bioluminescence imaging experiments, the targeted T cells were genetically tagged with CBR-luc (50). Six hours after spinoculation, 1 ml RPMI containing 50 IU mIL-2 was added, and the transduced T cells were used for experiments the next day.…”

Immuno-PET Imaging of Engineered Human T Cells in Tumors

“…Positron emission tomography (PET) imaging is a noninvasive imaging technology providing advantages due to high spatial and temporal information on cellular distribution with the potential for clinical translation (5). However, most T-cell imaging approaches using PET are far from clinical application and none has been yet clinically approved.…”

“…Promising novel approaches include the usage of reporter genes or antibody derivatives for imaging. Usage of reporter genes such as HSV1-tk has been closest to clinical translation with few patients treated, although technical and regulatory hurdles so far impede broader application (5,(11)(12)(13)(14)(15). In vivo imaging by Immuno-PET using antibody derivatives for targeting has been already clinically applied, although mainly for delineation of tumors (16).…”

Adoptively transferred TRAIL+ T cells suppress GVHD and augment antitumor activity

“…The final vector was labeled SFG-huTRAIL-IRES-GFP. The click beetle red luciferase encoding the SFG-CBRLuc-IRES-GFP retroviral vector was used as a GFP positive control vector (27). The PG13 viral producer cell line was transduced with the vectors mentioned above and selected based on GFP expression.…”

“…Forty-eight hours after stimulation with phytohemagglutinin (2 μg/ml; Fisher Scientific), T cells were transduced using GALV-pseudotyped retroviral particles obtained from transduced PG13 cells, as described previously (27), in the presence of human recombinant (hr)IL-2 (20 U/ml; R&D Systems). During T cell expansion, the medium was supplemented with hrIL-15 at a concentration of 10 ng/ml (R&D Systems).…”