Introducing micro physiological systems to evaluate new radiopharmaceuticals: A binding study with radiolabeled cetuximab

Abstract Radiopharmaceuticals can be used for targetspecific functional diagnostics, such as PET or SPECT imaging, radionuclide therapy of diseased tissue, depending on the incorporated radionuclide. Following initial in vitro testing, radiopharmaceutical candidates are usually further characterized small animals. Since reduction, replacement and refinement (3R) animal testing is a central precept preclinical research it would beneficial to replace at least some these tests by alternative methods. Using micro physiological system technology, various organ-on-chip models created with human cell systems/organoids, which operated circulatory under defined conditions. Here we present first attempts introduce systems evaluating radiopharmaceuticals using radiolabeled anti-EGFR antibody cetuximab reference compound. In equipped six 96-well plate-like microwells flow chamber, binding 64Cu 68Ga-labeled cells spheroids grown from A431 (EGFR-positive) MDA-MB435S (EGFR-negative) was measured compared conventional microplates. Specific saturation increasing concentrations analyzed phosphor imaging system. The affinity towards same range that Within assays systems, results showed trend increased monolayers spheroids. values capacity 2D 3D culture were order magnitude when Building promising results, work will continue MPS modules containing advanced spheroid/ organoid models.