New Compound Sets Identified from High Throughput Phenotypic Screening Against Three Kinetoplastid Parasites: An Open Resource

Abstract

Using whole-cell phenotypic assays, the GlaxoSmithKline high-throughput screening (HTS) diversity set of 1.8 million compounds was screened against the three kinetoplastids most relevant to human disease, i.e. Leishmania donovani, Trypanosoma cruzi and Trypanosoma brucei. Secondary confirmatory and orthogonal intracellular anti-parasiticidal assays were conducted, and the potential for non-specific cytotoxicity determined. Hit compounds were chemically clustered and triaged for desirable physicochemical properties. The hypothetical biological target space covered by these diversity sets was investigated through bioinformatics methodologies. Consequently, three anti-kinetoplastid chemical boxes of ~200 compounds each were assembled. Functional analyses of these compounds suggest a wide array of potential modes of action against kinetoplastid kinases, proteases and cytochromes as well as potential host–pathogen targets. This is the first published parallel high throughput screening of a pharma compound collection against kinetoplastids. The compound sets are provided as an open resource for future lead discovery programs, and to address important research questions.

Cos-Seq for high-throughput identification of drug target and resistance mechanisms in the protozoan parasite Leishmania

“…It is conceivable that these antiquated drugs act on multiple minor targets, which may correspond to some of the cosmids identified via Cos-Seq. More specific drugs are needed, and several active lead compounds are now publicly available (55). The Cos-Seq technique could be used with these new molecules to pinpoint their putative targets, which could be helpful for further drug improvements.…”

A Replicative In Vitro Assay for Drug Discovery against Leishmania donovani

“…Compound 1 (Table 1) was assayed as part of the highthroughput screening campaign against the kinetoplastids L. donovani, Trypanosoma cruzi, and Trypanosoma brucei (16). This compound, when tested in the FBS-containing media, exhibited a pEC 50 of 7.8 in the intramacrophage assay, as measured by the number of amastigotes/cell.…”

“…For in vitro screens and assays, this has ranged from the need to develop methods that (i) are adaptable to and enable high-throughput screens against the replicative intracellular-macrophage amastigote stage of Leishmania donovani, one of the causative species of VL (7); and (ii) include high-throughput technologies that enable the collection of more information compared to the traditionally used assays based on manual counting and reporter genes (8, 9). For example, highcontent screening (HCS) systems that permit the screening of large sets of compounds using imaging techniques that also capture information about compound toxicity against host cells and mode of action (10, 11) have been applied to antileishmanial drug discovery (12)(13)(14)(15)(16)(17).…”

“…The intramacrophage assay was adapted from de Rycker et al (14) and Peña et al (16). THP-1 cells were grown in Cell Master roller bottles (Greiner catalog no.…”

Open Lab as a source of hits and leads against tuberculosis, malaria and kinetoplastid diseases

“…The first step in GSK's open-innovation strategy involved the public release of proprietary data generated during various drugscreening campaigns, exemplified in the Tres Cantos antimalarial, antitubercular and antikinetoplastid compound collections and data sets [2][3][4][5] . The objective of releasing this information through a number of freely accessible databases was to provide small molecules as starting points for synthetic drug lead generation by the wider scientific community.…”