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Updated: Nov 11, 2025

A High-Throughput Luciferase Assay to Evaluate Proteolysis of the Single-Turnover Protease PCSK9
Published on: August 28, 2018
Increased Valency Improves Inhibitory Activity of Peptides Targeting Proprotein Convertase Subtilisin/Kexin Type 9
Benjamin J Tombling1, Carmen Lammi2, Carlotta Bollati2
1Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Qld, 4072, Australia.
Abstract:
Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a clinically validated target for treating hypercholesterolemia. Peptide-based PCSK9 inhibitors have attracted pharmaceutical interest, but the effect of multivalency on bioactivity is poorly understood. Here we designed bivalent and tetravalent dendrimers, decorated with the PCSK9 inhibitory peptides Pep2-8[RRG] or P9-38, to study relationships between peptide binding affinity, peptide valency, and PCSK9 inhibition. Increased valency resulted in improved PCSK9 inhibition for both peptides, with activity improvements of up to 100-fold achieved for the P9-38-decorated dendrimers compared to monomeric P9-38 in in vitro competition binding assays. Furthermore, the P9-38-decorated dendrimers showed improved potency at restoring functional low-density lipoprotein (LDL) receptor levels and internalizing LDL in the presence of PCSK9, demonstrating significant cell-based activity at picomolar concentrations. This study demonstrates the potential of increasing valency as a strategy for increasing the efficacy of peptide-based PCSK9 therapeutics.
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