Comparison of the Accuracy of FMT/CT and PET/MRI for the Assessment of Antibody Biodistribution in Squamous Cell Carcinoma Xenografts

• DOI: 10.2967/jnumed.117.197178
• Publication Date: 2017-08-29T00:10:32Z
• Authors: Carina Hage; Felix Gremse; Christoph M. Grie...; Andreas Maurer; Sabrina H.L. Hoff...; Franz Osl; Bernd J. Pichler; Fabian Kiessling; Werner Scheuer; Thomas Pöschinger
• Keywords: Biodistribution; Ex vivo; Imaging agent

Noninvasive imaging technologies are increasingly used in preclinical drug research for the pharmacokinetic analysis of therapeutic compounds living animals over time. The different modalities available differ intrinsically their detection principle and thus might exhibit limitations a specific application. Here, we systematically investigated performance advanced fluorescence-mediated tomography (FMT)/CT comparison to PET/MRI quantitative biodistribution antibody formats dependence on required label squamous cell carcinoma xenografts. <b>Methods:</b> Different an (monoclonal antigen binding fragments F(ab′)₂ Fab) targeting epidermal growth factor receptor were labeled with Alexa750 or ⁶⁴Cu-NODAGA injected intravenously into separate cohorts nude mice bearing subcutaneous A-431 tumors. Two 24 h after injection, measured by FMT/CT PET/MRI. Probe accumulation was quantitatively assessed organs In vivo data compared between correlated ex fluorescence, γ-counting, electrochemiluminescence immunoassay. <b>Results:</b> Both methods faithfully monitored elimination routes compounds, organ significantly measurements. addition, kidney, muscle, tumor tissue However, pharmacokinetics Alexa750-labeled showed shorter blood half-times higher liver uptake than radiolabeled counterparts. <b>Conclusion:</b> allows quantifying antibodies provides alternative PET research. even large molecules, such as monoclonal antibodies, labeling can change trigger uptake.