Deconvoluting the mode of action of a suite of novel antileishmanials

Lead Research Organisation: Durham University
Department Name: Chemistry

Abstract

Leishmania spp protozoan parasites are responsible for the Neglected Tropical Disease leishmaniasis, affecting over 12 million people worldwide, with more than 1 billion at risk. With an increasing number of cases in an ever wider geographical area, and rising antimicrobial resistance, the battle against has been described as a 'losing one'. Current therapies are limited, expensive, difficult to administer and not widely accessible. Working in partnership, GSK has identified many new promising antileishmanials. To develop these further, we need to understand how they work (the Mode of Action; MoA). In this project we will using biological and biophysical technologies to uncover the mode of action of 17 hits selected for their efficacy, non-toxic profile and physical-chemical properties:
Work Package 1: Laboratory induction of antimicrobial resistance has long been observed and Next Generation Sequencing (NGS) now allows the relatively rapid identification of associated mutations in Leishmania species. Leishmania (New World L. mexicana and Old World L. major) resistance to the GSK compounds (Month 1 to 12) will be induced by in vitro evolution via stepwise increase in compound concentrations. Whole genome sequencing and evaluation of the Mode of Resistance (MoR, Month 12 to 18) using available NGS and analytical platforms will allow mutations associated with resistance will be evaluated. Validation of MoR by using gene editing technology by mutation reversal and restoration of compound sensitivity will then complete the Work Package (Month 18-36).
Work Package 2: Compounds with induced MoR mutations which have been genetically validated will then enter stage 2, where further validation will be undertaken using mass spectrometry approaches. Such technologies are now well established for the characterization of the response of cells to chemical stress and are widely utilised in the deconvolution of drug MoA, including in the laboratories of the Newcastle supervisor, Prof Matthias Trost. With Trost, leading edge mass spectrometry-based cellular thermal shift assay (MS-CeTSA; thermal proteomics) will be employed to further deconvolute the MoA of the triaged compounds (Month 24-36). MS-CeTSA allows changes in protein thermal stability associated with ligand (e.g. drug) interaction to be identified and quantified, thus facilitating the identification of drug targets in live cells (Miettinen et al, 2018). These data will be added and compared to that generated above.
Work Package 3: Compound targets fully validated in Work Packages 1 and 2 will be assessed at GSK for 'druggability', triaged and formatted into assay platforms for future HTS campaigns. In parallel, GSK medicinal chemistry expertise will assess the compounds directed at these targets for entry into hit-to-lead programmes (Month 36-42).
Write up: Month 42-48.

Publications

10 25 50

Studentship Projects

Project Reference Relationship Related To Start End Student Name
EP/S022791/1 01/05/2019 31/10/2027
2304113 Studentship EP/S022791/1 01/10/2019 30/09/2023 Laura Nunes Filipe