Aptamer BT200 blocks interaction of K1405-1408 in the VWF-A1 domain with macrophage LRP1

Chan Kwo Chion, Alain; Byrne, Ciara; Atiq, Ferdows; Doherty, Dearbhla; Aguila, Sonia; Fazavana, Judicael; Lopes, Patricia; Karampini, Ellie; Amin, Aamir; Preston, Roger J.S.; Baker, Ross Ian; McKinnon, Thomas AJ; Zhu, Shuhao; Gilbert, James C.; Emsley, Jonas; Jilma, Bernd; O'Donnell, James S.

Abstract

Rondaptivan pegol (previously BT200) is a PEGylated RNA aptamer that binds to the A1 domain of VWF. Recent clinical trials demonstrated that BT200 significantly increased plasma VWF-FVIII levels by attenuating VWF clearance. The biological mechanism(s) through which BT200 attenuates in vivo clearance of VWF have not been defined. We hypothesized that BT200 interaction with the VWF-A1 domain may increase plasma VWF levels by attenuating macrophage-mediated clearance. We observed that full length- and VWF-A1A2A3 binding to macrophages, and VWF-A1 domain binding to LRP1 cluster II and cluster IV, were concentration-dependently inhibited by BT200. Additionally, full length VWF binding to LRP1 expressed on HEK293T (HEK-LRP1) cells was also inhibited by BT200. Importantly, BT200 interacts with the VWF-A1 domain in proximity to a conserved cluster of four lysine residues (K1405, K1406, K1407 and K1408). Alanine mutagenesis of this K1405-K1408 cluster (VWF-4A) significantly (p<0.001) attenuated binding of VWF to both LRP1 clusters II and IV. Furthermore, in vivo clearance of VWF-4A was significantly (p<0.001) reduced compared to wild type VWF. BT200 did not significantly inhibit binding of VWF-4A to LRP1 cluster IV or HEK-LRP1 cells. Finally, BT200 interaction with the VWF-A1 domain also inhibited binding to macrophage galactose lectin (MGL) and the SR-AI scavenger receptor. Collectively, our findings demonstrate that BT200 prolongs VWF half-life by attenuating macrophage-mediated clearance and specifically the interaction of K1405-1408 in the VWF-A1 domain with macrophage LRP1. These data support the concept that targeted inhibition of VWF clearance pathways represent a novel therapeutic approach for VWD and hemophilia A.

Citation

Chan Kwo Chion, A., Byrne, C., Atiq, F., Doherty, D., Aguila, S., Fazavana, J., Lopes, P., Karampini, E., Amin, A., Preston, R. J., Baker, R. I., McKinnon, T. A., Zhu, S., Gilbert, J. C., Emsley, J., Jilma, B., & O'Donnell, J. S. (2024). Aptamer BT200 blocks interaction of K1405-1408 in the VWF-A1 domain with macrophage LRP1. Blood, https://doi.org/10.1182/blood.2024024055

• Journal Article Type: Article
• Acceptance Date: Jul 3, 2024
• Online Publication Date: Jul 12, 2024
• Publication Date: Jan 1, 2024
• Deposit Date: Jul 16, 2024
• Journal: Blood
• Print ISSN: 0006-4971
• Electronic ISSN: 1528-0020
• Publisher: American Society of Hematology
• Peer Reviewed: Peer Reviewed
• DOI: https://doi.org/10.1182/blood.2024024055
• Public URL: https://nottingham-repository.worktribe.com/output/37158567
• Publisher URL: https://ashpublications.org/blood/article/doi/10.1182/blood.2024024055/517007/Aptamer-BT200-blocks-interaction-of-K1405-1408-in