{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["MacPherson DS"],"funding":["Academy of Finland","NIBIB NIH HHS","NCRR NIH HHS","NIEHS NIH HHS","National Cancer Institute","NCI NIH HHS","National Institute of Biomedical Imaging and Bioengineering","NIH HHS"],"pagination":["775-782"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC10263003"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["20(1)"],"pubmed_abstract":["Site-specifically modified radioimmunoconjugates exhibit superior <i>in vitro</i> and <i>in vivo</i> behavior compared to analogues synthesized via traditional stochastic methods. However, the development of approaches to site-specific bioconjugation that combine high levels of selectivity, simple reaction conditions, and clinical translatability remains a challenge. Herein, we describe a novel solution to this problem: the use of dual-variable domain immunoglobulins (DVD-IgG). More specifically, we report the synthesis, <i>in vitro</i> evaluation, and <i>in vivo</i> validation of a <sup>177</sup>Lu-labeled radioimmunoconjugate based on <sup>HER2</sup>DVD, a DVD-IgG containing the HER2-targeting variable domains of trastuzumab and the catalytic variable domains of IgG h38C2. To this end, we first modified <sup>HER2</sup>DVD with a phenyloxadiazolyl methlysulfone-modified variant of the chelator CHX-A″-DTPA (PODS-CHX-A''-DTPA) and verified the site-specificity of the conjugation for the reactive lysines within the catalytic domains via chemical assay, MALDI-ToF mass spectrometry, and SDS-PAGE. The chelator-bearing immunoconjugate was subsequently labeled with [<sup>177</sup>Lu]Lu<sup>3+</sup> to produce the completed radioimmunoconjugate, [<sup>177</sup>Lu]Lu-CHX-A″-DTPA<sub>PODS</sub>-<sup>HER2</sup>DVD, in >80% radiochemical conversion and a specific activity of 29.5 ± 7.1 GBq/μmol. [<sup>177</sup>Lu]Lu-CHX-A″-DTPA<sub>PODS</sub>-<sup>HER2</sup>DVD did not form aggregates upon prolonged incubation in human serum, displayed 87% stability to demetalation over a 7 days of incubation in serum, and exhibited an immunoreactive fraction of 0.95 with HER2-coated beads. Finally, we compared the pharmacokinetic profile of [<sup>177</sup>Lu]Lu-CHX-A″-DTPA<sub>PODS</sub>-<sup>HER2</sup>DVD to that of a <sup>177</sup>Lu-labeled variant of trastuzumab in mice bearing subcutaneous HER2-expressing BT-474 human breast cancer xenografts. The <i>in vivo</i> performance of [<sup>177</sup>Lu]Lu-CHX-A″-DTPA<sub>PODS</sub>-<sup>HER2</sup>DVD matched that of <sup>177</sup>Lu-labeled trastuzumab, with the former producing a tumoral activity concentration of 34.1 ± 12.1 %ID/g at 168 h and tumor-to-blood, tumor-to-liver, and tumor-to-kidney activity concentration ratios of 10.5, 9.6, and 21.8, respectively, at the same time point. Importantly, the DVD-IgG did not exhibit a substantially longer serum half-life than the traditional IgG despite its significantly larger size (202 kDa for the former vs 148 kDa for the latter). Taken together, these data suggest that DVD-IgGs represent a viable platform for the future development of highly effective site-specifically labeled radioimmunoconjugates for diagnostic imaging, theranostic imaging, and radioimmunotherapy."],"journal":["Molecular pharmaceutics"],"pubmed_title":["Leveraging a Dual Variable Domain Immunoglobulin to Create a Site-Specifically Modified Radioimmunoconjugate."],"pmcid":["PMC10263003"],"funding_grant_id":["S10 RR020892","R01 CA244327","331659","K99 ES034053","P30 CA008748","R21 EB030275","S10 OD016207","U01CA221046","U01 CA221046","R01CA240963","R01 CA174844","R01 CA204167","R01 CA204484","R01CA204484","R01 CA240963","R21EB030275","R01CA244327","R01CA204167"],"pubmed_authors":["Rader C","MacPherson DS","Hwang D","Keinanen O","Sarrett SM","Rodriguez C","Zeglis BM"],"additional_accession":[]},"is_claimable":false,"name":"Leveraging a Dual Variable Domain Immunoglobulin to Create a Site-Specifically Modified Radioimmunoconjugate.","description":"Site-specifically modified radioimmunoconjugates exhibit superior <i>in vitro</i> and <i>in vivo</i> behavior compared to analogues synthesized via traditional stochastic methods. However, the development of approaches to site-specific bioconjugation that combine high levels of selectivity, simple reaction conditions, and clinical translatability remains a challenge. Herein, we describe a novel solution to this problem: the use of dual-variable domain immunoglobulins (DVD-IgG). More specifically, we report the synthesis, <i>in vitro</i> evaluation, and <i>in vivo</i> validation of a <sup>177</sup>Lu-labeled radioimmunoconjugate based on <sup>HER2</sup>DVD, a DVD-IgG containing the HER2-targeting variable domains of trastuzumab and the catalytic variable domains of IgG h38C2. To this end, we first modified <sup>HER2</sup>DVD with a phenyloxadiazolyl methlysulfone-modified variant of the chelator CHX-A″-DTPA (PODS-CHX-A''-DTPA) and verified the site-specificity of the conjugation for the reactive lysines within the catalytic domains via chemical assay, MALDI-ToF mass spectrometry, and SDS-PAGE. The chelator-bearing immunoconjugate was subsequently labeled with [<sup>177</sup>Lu]Lu<sup>3+</sup> to produce the completed radioimmunoconjugate, [<sup>177</sup>Lu]Lu-CHX-A″-DTPA<sub>PODS</sub>-<sup>HER2</sup>DVD, in >80% radiochemical conversion and a specific activity of 29.5 ± 7.1 GBq/μmol. [<sup>177</sup>Lu]Lu-CHX-A″-DTPA<sub>PODS</sub>-<sup>HER2</sup>DVD did not form aggregates upon prolonged incubation in human serum, displayed 87% stability to demetalation over a 7 days of incubation in serum, and exhibited an immunoreactive fraction of 0.95 with HER2-coated beads. Finally, we compared the pharmacokinetic profile of [<sup>177</sup>Lu]Lu-CHX-A″-DTPA<sub>PODS</sub>-<sup>HER2</sup>DVD to that of a <sup>177</sup>Lu-labeled variant of trastuzumab in mice bearing subcutaneous HER2-expressing BT-474 human breast cancer xenografts. The <i>in vivo</i> performance of [<sup>177</sup>Lu]Lu-CHX-A″-DTPA<sub>PODS</sub>-<sup>HER2</sup>DVD matched that of <sup>177</sup>Lu-labeled trastuzumab, with the former producing a tumoral activity concentration of 34.1 ± 12.1 %ID/g at 168 h and tumor-to-blood, tumor-to-liver, and tumor-to-kidney activity concentration ratios of 10.5, 9.6, and 21.8, respectively, at the same time point. Importantly, the DVD-IgG did not exhibit a substantially longer serum half-life than the traditional IgG despite its significantly larger size (202 kDa for the former vs 148 kDa for the latter). Taken together, these data suggest that DVD-IgGs represent a viable platform for the future development of highly effective site-specifically labeled radioimmunoconjugates for diagnostic imaging, theranostic imaging, and radioimmunotherapy.","dates":{"release":"2023-01-01T00:00:00Z","publication":"2023 Jan","modification":"2025-04-05T11:27:29.509Z","creation":"2025-04-05T11:27:29.509Z"},"accession":"S-EPMC10263003","cross_references":{"pubmed":["36377696"],"doi":["10.1021/acs.molpharmaceut.2c00700"]}}