Proposed is the development of a simple, fast and universal strategy for incorporating radionuclides into biomolecules for applications for cancer imaging and pretargeted immunotherapy. The strategy is based on a bioconjugation reaction developed in the Fox laboratories: the reaction between tetrazines and trans- cyclooctenes (TCO). The fast kinetics of the 'tetrazine-TCO ligation'(k2 e 250,000 L?mol/s-1) enable fast reactivity at low micromolar concentrations within minutes and without an excess of either reactant. This fast reactivity provides unprecedented opportunities for protein and antibody modification and for performing reactions in vivo. This proposal involves collaborative effort from the Molecular Imaging Center (MIC) at University of Southern California (USC) and the Fox group (UD). An objective of this application is to use the tetrazine ligation to develop efficient methods for the construction of 18F labeled proteins with high specific activity for cancer imaging. Moreover, we will also develop a novel pretargeted imaging and radioimmunotherapy method that will allow for universal and straightforward tagging of monoclonal antibodies (mAbs) with an imaging/therapeutic isotope without severe radiation exposure towards normal organs. To achieve these objectives, we will first develop bioconjugation reactions with fast kinetics and robust in vivo stability based on the tetrazine-TCO ligation. As the fast kinetics of tetrazine-TCO ligation enable fast reactivity at low micromolar concentrations within minutes and without an excess of either reactant, we will transform this reaction into efficient methods that could be used for the construction of 18F labeled proteins with high specific activity. At last, we will also establish a chemical pretargeting approach that for pretargeted imaging/radioimmunotherapy of cancer based on the tetrazine-TCO ligation and anti-EphB4 antibody. In summary, in this application, we are developing efficient methods for proteins labeling with 18F, and a chemical pretargeting approach that could be used for pretargeted imaging and radioimmunotherapy of breast cancer. The feasibility of these approaches will be tested with EphB4 antibody, F(ab')2, and Fab. The success of these novel imaging and therapy approached could enable breast cancer diagnosis, make possible direct monitoring of responses to therapeutic interventions, and may significantly improve breast cancer treatment efficacy. Moreover, these newly developed approaches could have important applications in many other cancer types, and thus have a significant clinical impact on a very large number of cancer patients

Public Health Relevance

In this collaborative project, we will develop efficient methods for the construction of 18F labeled proteins (including antibody fragments) with high specific activity for breast cancer imaging. Moreover, we will develop a novel pretargeted method that would in principle allow universal and straightforward tagging of mAbs with an imaging or therapeutic isotope with only limit radiation exposure of normal organs.

National Institute of Health (NIH)
National Institute of Biomedical Imaging and Bioengineering (NIBIB)
Research Project (R01)
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Clinical Molecular Imaging and Probe Development (CMIP)
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Sastre, Antonio
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University of Southern California
Schools of Medicine
Los Angeles
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Smith, Natalee J; Rohlfing, Katarina; Sawicki, Lisa A et al. (2018) Fast, irreversible modification of cysteines through strain releasing conjugate additions of cyclopropenyl ketones. Org Biomol Chem 16:2164-2169
O'Brien, Jessica G K; Chintala, Srinivasa R; Fox, Joseph M (2018) Stereoselective Synthesis of Bicyclo[6.1.0]nonene Precursors of the Bioorthogonal Reagents s-TCO and BCN. J Org Chem 83:7500-7503
Fang, Yinzhi; Zhang, Han; Huang, Zhen et al. (2018) Photochemical syntheses, transformations, and bioorthogonal chemistry of trans-cycloheptene and sila trans-cycloheptene Ag(i) complexes. Chem Sci 9:1953-1963
Mao, Chengqiong; Qu, Ping; Miley, Michael J et al. (2018) P-glycoprotein targeted photodynamic therapy of chemoresistant tumors using recombinant Fab fragment conjugates. Biomater Sci 6:3063-3074
Lambert, William D; Scinto, Samuel L; Dmitrenko, Olga et al. (2017) Computationally guided discovery of a reactive, hydrophilic trans-5-oxocene dienophile for bioorthogonal labeling. Org Biomol Chem 15:6640-6644
Giglio, Benjamin C; Fei, Haiyang; Wang, Mengzhe et al. (2017) Synthesis of 5-[18F]Fluoro-?-methyl Tryptophan: New Trp Based PET Agents. Theranostics 7:1524-1530
Wang, Mengzhe; Mao, Chengqiong; Wang, Hui et al. (2017) Molecular Imaging of P-glycoprotein in Chemoresistant Tumors Using a Dual-Modality PET/Fluorescence Probe. Mol Pharm 14:3391-3398
Wang, Mengzhe; Svatunek, Dennis; Rohlfing, Katarina et al. (2016) Conformationally Strained trans-Cyclooctene (sTCO) Enables the Rapid Construction of (18)F-PET Probes via Tetrazine Ligation. Theranostics 6:887-95
Wang, Hui; Li, Dan; Liu, Shuanglong et al. (2015) Small-Animal PET Imaging of Pancreatic Cancer Xenografts Using a 64Cu-Labeled Monoclonal Antibody, MAb159. J Nucl Med 56:908-13
Chansaenpak, Kantapat; Wang, Mengzhe; Wu, Zhanhong et al. (2015) [(18)F]-NHC-BF3 adducts as water stable radio-prosthetic groups for PET imaging. Chem Commun (Camb) 51:12439-42

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