Developing an artificial intelligence-generated peptide targeting platelet-type von Willebrand disease

Platelet-type von Willebrand disease (PT-VWD) refers to a rare bleeding disorder caused by gain-of-function mutations in platelet glycoprotein Ibα (GPIbα). These mutations lead to a hyperactive protein-protein interaction (PPI) with von Willebrand factor (VWF) and pathological platelet aggregation. Counterintuitively, patients with PT-VWD present with a bleeding diathesis as opposed to thrombosis. Despite well-defined genetic etiology, no targeted therapy exists for PT-VWD. Here, we sought to develop a peptide inhibitor that selectively targets the aberrant interaction in PT-VWD. Using the In Silico Protein Synthesizer, we designed and screened 10 000 peptides for predicted affinity and specificity toward GPIbαMet239Val. Functional validation of top-ranked peptides included a combination of in vitro functional assays using GPIbαGly233Val, Met239Val and ex vivo platelet assays from patients with PT-VWD. One peptide, G14, emerged as a potent and selective inhibitor of the GPIbαGly233Val, Met239Val-VWF PPI. Functional assays demonstrated that G14 disrupts this interaction without binding GPIbαWT or VWF alone. The peptide also displays picomolar affinity (6.6 pM) for GPIbαGly233Val, Met239Val. Structural modeling predicted G14 binds the β-switch region of GPIbαGly233Val, Met239Val involving the disease-associated Val239 residue. In platelet-rich plasma from a patient with PT-VWD, G14 selectively inhibited platelet-VWF binding and ristocetin-induced agglutination, with no measurable effect on healthy samples. The G14 peptide appears to be a highly specific inhibitor of the GPIbαGly233Val, Met239Val-VWF interaction, providing proof-of-concept data for therapeutic development in PT-VWD. Furthermore, the protein and platelet specificity of these data suggest that G14 may be a potential diagnostic tool for PT-VWD. The approach highlights the utility of artificial intelligence in targeting disease-specific PPIs with high precision.