User Story: Prof. Emiliano Biasini, University of Trento, Italy

User:

Prof. Emiliano Biasini, Department of Cellular, Computational and Integrative Biology (CIBIO), University of Trento, Italy
Prof. Maria Letizia Barreca and Prof. Giuseppe Manfroni, Department of Pharmaceutical Sciences, University of Perugia, Italy
Prof. Francesca Fallarino, Department of Medicine and Surgery, University of Perugia, Italy

EU-OPENSCREEN-DRIVE screening partner

Prof. Dr Kuster, Technische Universität München (TUM), Germany
Dr Guillaume Médard, Technische Universität München (TUM), Germany

Prion diseases are rare and fatal neurodegenerative disorders, characterised by the formation of pathogenic protein aggregates, which can affect the brains of mammals. In humans, known prion diseases include Creutzfeldt−Jakob disease (CJD), Gerstmann-Sträussler-Scheinker (GSS) syndrome, and Fatal Familial Insomnia (FFI). These pathologies can be genetic in origin, be transmitted horizontally, or manifest spontaneously.

All forms of prion disease share a common pathogenic mechanism: the conversion of a normal host protein (PrP) into a toxic and infectious form (PrPSc). PrPSc, a misfolded version of PrP, can propagate as an infectious agent by inducing the misfolding of PrP molecules on the surface of nearby neurons, thereby generating new PrPSc molecules. PrPSc molecules subsequently accumulate in the brain and cause neuronal death. A similar mechanism occurs in genetic forms of prion diseases, in which specific mutations alter the stability and normal function of PrP.
Currently, there are no effective treatments or cures for prion disease. The research group of Prof. Emiliano Biasini, Department of Cellular, Computational and Integrative Biology (CIBIO), University of Trento, Italy, however, aims to develop a novel therapeutic strategy for this group of diseases.

Emiliano’s group has employed a laboratory test to identify pharmacological agents counteracting the toxicity of mutant PrP molecules, which has yielded a class of compounds capable of strongly suppressing the toxic effects of mutant PrP in various experimental settings. Over the past seven years, they have worked to optimise these chemicals for use in patients with prion disease. However, they have now recognised a need for more knowledge about the pharmacological targets and mechanisms of action of these compounds.

To overcome this key limitation, Emiliano and his colleagues Prof. Maria Letizia Barreca, Prof. Giuseppe Manfroni, and Prof. Francesca Fallarino, University of Perugia, Italy, collaborated with researchers Luna Bergamasco and Dr Guillaume Médard of the EU-OPENSCREEN-DRIVE site, Technische Universität München (TUM), to explore potential applications for chemoproteomics in their research. This cutting-edge technology defines how small molecules interact with target proteins across an entire proteome. The approach has already been employed to elucidate the mode of action of several drug candidates and, in this project, was exploited to identify the pharmacological targets of candidate compounds for the treatments of prion disease.

To do so, two potent compounds were subjected to chemoproteomic target deconvolution experiments at TUM. Briefly, a linkable version of the molecules was immobilised on sepharose beads. The free compounds of interest were pre-incubated with complex native HEK293 lysate to enable target protein binding. Then, free and immobilised compounds could compete for the same binding site, leading to a dose-dependent signal reduction of target proteins in a quantitative label-free proteomics readout. This experimental setup revealed three protein targets bound by both compounds of interest with nanomolar affinity.

According to Emiliano, the collaboration with TUM was instrumental in the identification of a promising candidate protein as a primary pharmacological target. The validation of the identified protein could profoundly impact the field's understanding of the neurotoxic mechanisms underlying prion diseases and may provide an opportunity for the structure-based rational optimisation of candidate compounds.

Emiliano and his group are now in the planning and implementation phase for several in vitro, cell-based, and in vivo experiments to validate the protein identified in this EU-OPENSCREEN-DRIVE project as the target of their compounds. They further aim to assess its precise role in prion disease toxicity.