Abstract
Rationale: CR3022 is a human antibody which binds to the SARS-CoV-2 virus. Here, we explore the use of CR3022 as a molecularly targeted radiotherapeutic. Methods: CR3022 was labeled with Iodine-131 using the Iodogen-method and purified, yielding 131I-CR3022. Using a magnetic bead assay and a recombinant SARS-CoV-2 spike protein fragment, we tested binding of 131I-CR3022 in the presence and absence of CR3022. Results: We conjugated the antibody CR3022 with a purity > 98% and a molar activity >7.9 mCi/mg. Using a bead-based assay, we confirmed that binding of 131I-CR3022 is selective, and is significantly reduced in the presence of unlabeled antibody (3.14 ± 0.14 specific uptake and 0.10 ± 0.01 specific uptake, respectively; P < 0.0001). Conclusion: Our results confirm the potential of CR3022 as a molecularly targeted probe for SARS-CoV-2. A labeled version of CR3022 could potentially be used for Auger radiotherapy or non-invasive imaging.
Footnotes
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