PB0390 - Identification of novel inhibitors of the platelet collagen receptor GPVI by a phenotypic screening assay

Sunday, July 10, 2022

6:30 PM – 7:30 PM

Location: Exhibition

Presentation Format: In-Person

Presenting Author(s)

Sara Troitiño

PhD Student
Platelet Proteomics Group, Center for Research in Molecular Medicine and Chronic Diseases (CiMUS), Universidade de Santiago de Compostela, Santiago de Compostela, Spain
Santiago de Compostela, Galicia, Spain

Co-Author(s)

II

Irene Izquierdo

PhD
Platelet Proteomics Group, Center for Research in Molecular Medicine and Chronic Diseases (CiMUS), Universidade de Santiago de Compostela, Santiago de Compostela, Spain
Santiago De Compostela, Galicia, Spain
NG

Nuria Gómez-Romero

Master Student
Platelet Proteomics Group, Center for Research in Molecular Medicine and Chronic Diseases (CiMUS), Universidade de Santiago de Compostela, Santiago de Compostela, Spain
Santiago De Compostela, Galicia, Spain
FR

Francisco J. Rodríguez Del Río

Degree Student
Platelet Proteomics Group, Center for Research in Molecular Medicine and Chronic Diseases (CiMUS), Universidade de Santiago de Compostela, Santiago de Compostela, Spain
Santiago De Compostela, Galicia, Spain
GP

Gema Prieto Da Cuña

Master Student
Platelet Proteomics Group, Center for Research in Molecular Medicine and Chronic Diseases (CiMUS), Universidade de Santiago de Compostela, Santiago de Compostela, Spain
Santiago De Compostela, Galicia, Spain
Lidia Hermida-Nogueira

PhD
Platelet Proteomics Group, Center for Research in Molecular Medicine and Chronic Diseases (CiMUS), Universidade de Santiago de Compostela, Santiago de Compostela, Spain
Santiago de Compostela, Galicia, Spain
ED

Eduardo Domínguez

PhD
Innopharma Screening Platform, BioFarma Research group, Center for Research in Molecular Medicine and Chronic Diseases (CIMUS), Universidade de Santiago de Compostela, Santiago de Compostela, Spain
Santiago De Compostela, Galicia, Spain
ML

María I. Loza

Professor
Head of Innopharma Screening Platform, BioFarma Research group, Center for Research in Molecular Medicine and Chronic Diseases (CIMUS), Universidade de Santiago de Compostela, Santiago de Compostela, Spain
Santiago De Compostela, Galicia, Spain
AG

Angel Garcia

Professor
Universidade de Santiago de Compostela
Santiago de Compostela, Galicia, Spain

Background: Current antiplatelet therapies are often associated with significant risks of bleeding and haemorrhage by seriously compromising platelet function. Finding antiplatelet drugs modulating thrombus formation without significantly altering haemostasis is a need. The collagen receptor glycoprotein VI (GPVI) is a promising candidate, since not only is uniquely expressed in platelets and megakaryocytes, but also its blockade inhibits thrombosis.

Aims: To identify GPVI potential inhibitors by phenotypic screening that can progress into preclinical trials as novels antithrombotic candidates.

Methods: Platelet-based intracellular calcium mobilization (FLIPR Calcium 4) phenotypic screen assay was used to identify inhibitors. Label-free dynamic mass redistribution assay was carried out to confirm ligand binding. Series of derivatives of the hits obtained were synthesized by using a medicinal chemistry strategy. Functional studies were based on platelet aggregation and spreading assays. Viability Calcein-AM assay by flow cytometry was used to test the potential toxicity of ligands.

Results: Two molecules showing efficacy at inhibiting intracellular calcium release and platelet aggregation through GPVI modulation, SIL-ENA and SEDN2, were identified as ligands. SEDN2 was the most potent aggregation inhibitor and was used as a scaffold to obtain 19 chemical derivatives. Two of those derivatives showed a potent antiplatelet activity and were prioritized, together with SEDN2, as candidates for preclinical thrombosis studies. The candidates have negligible effects in platelet viability at micromolar doses. We are performing studies to further characterize their antithrombotic potential in vivo by evaluating their selectivity and bioavailability.

Conclusion(s): Novel antiplatelet agents targeting GPVI were identified and prioritized by combining relevant phenotypic screens and functional studies in human platelets.