Effect of Inter-Domain Linker Composition on Biodistribution of ABD-Fused Affibody-Drug Conjugates Targeting HER2
Tianqi Xu,
Jie Zhang,
Maryam Oroujeni,
Maria S. Tretyakova,
Vitalina Bodenko,
Mikhail V. Belousov,
Anna Orlova,
Vladimir Tolmachev,
Anzhelika Vorobyeva,
Torbjörn Gräslund
Affiliations
Tianqi Xu
Department of Immunology, Genetics and Pathology, Uppsala University, 751 85 Uppsala, Sweden
Jie Zhang
Department of Protein Science, KTH Royal Institute of Technology, Roslagstullsbacken 21, 114 17 Stockholm, Sweden
Maryam Oroujeni
Department of Immunology, Genetics and Pathology, Uppsala University, 751 85 Uppsala, Sweden
Maria S. Tretyakova
Research Centrum for Oncotheranostics, Research School of Chemistry and Applied Biomedical Sciences, Tomsk Polytechnic University, 634050 Tomsk, Russia
Vitalina Bodenko
Research Centrum for Oncotheranostics, Research School of Chemistry and Applied Biomedical Sciences, Tomsk Polytechnic University, 634050 Tomsk, Russia
Mikhail V. Belousov
Department of Pharmaceutical Analysis, Siberian State Medical University, Ministry of Health of the Russian Federation, 634050 Tomsk, Russia
Anna Orlova
Research Centrum for Oncotheranostics, Research School of Chemistry and Applied Biomedical Sciences, Tomsk Polytechnic University, 634050 Tomsk, Russia
Vladimir Tolmachev
Department of Immunology, Genetics and Pathology, Uppsala University, 751 85 Uppsala, Sweden
Anzhelika Vorobyeva
Department of Immunology, Genetics and Pathology, Uppsala University, 751 85 Uppsala, Sweden
Torbjörn Gräslund
Department of Protein Science, KTH Royal Institute of Technology, Roslagstullsbacken 21, 114 17 Stockholm, Sweden
Targeted drug conjugates based on Affibody molecules fused to an albumin-binding domain (ABD) for half-life extension have demonstrated potent anti-tumor activity in preclinical therapeutic studies. Furthermore, optimization of their molecular design might increase the cytotoxic effect on tumors and minimize systemic toxicity. This study aimed to investigate the influence of length and composition of a linker between the human epidermal growth factor receptor 2 (HER2)-targeted affibody molecule (ZHER2:2891) and the ABD domain on functionality and biodistribution of affibody-drug conjugates containing a microtubulin inhibitor mertansin (mcDM1) (AffiDCs). Two conjugates, having a trimeric (S3G)3 linker or a trimeric (G3S)3 linker were produced, radiolabeled with 99mTc(CO)3, and compared side-by-side in vitro and in vivo with the original ZHER2:2891-G4S-ABD-mcDM1 conjugate having a monomeric G4S linker. Both conjugates with longer linkers had a decreased affinity to HER2 and mouse and human serum albumin in vitro, however, no differences in blood retention were observed in NMRI mice up to 24 h post injection. The use of both (S3G)3 and (G3S)3 linkers reduced liver uptake of AffiDCs by approximately 1.2-fold compared with the use of a G4S linker. This finding provides important insights into the molecular design for the development of targeted drug conjugates with reduced hepatic uptake.
