Development and optimization of a high-throughput screening method utilizing Ancylostoma ceylanicum egg hatching to identify novel anthelmintics

PLoS One. 2019 Jun 3;14(6):e0217019. doi: 10.1371/journal.pone.0217019. eCollection 2019.

Abstract

Hookworms remain a major health burden in the developing world, with hundreds of millions currently afflicted by these blood-feeding parasites. There exists a vital need for the discovery of novel drugs and identification of parasite drug targets for the development of chemotherapies. New drug development requires the identification of compounds that target molecules essential to parasite survival and preclinical testing in robust, standardized animal models of human disease. This process can prove costly and time consuming using conventional, low-throughput methods. We have developed a novel high-throughput screen (HTS) to identify anthelmintics for the treatment of soil-transmitted helminths. Our high-throughput, plate reader-based assay was used to rapidly assess compound toxicity to Ancylostoma ceylanicum L1 larva. Using this method, we screened 39,568 compounds from several small molecule screening libraries at 10 μM and identified 830 bioactive compounds that inhibit egg hatching of the human hookworm A. ceylanicum by >50%. Of these, 132 compounds inhibited hookworm egg hatching by >90% compared to controls. The nematicidal activities of 268 compounds were verified by retesting in the egg hatching assay and were also tested for toxicity against the human HeLa cell line at 10 μM. Fifty-nine compounds were verified to inhibit A. ceylanicum egg hatching by >80% and were <20% toxic to HeLa cells. Half-maximal inhibitory concentration (IC50) values were determined for the 59 hit compounds and ranged from 0.05-8.94 μM. This stringent advancement of compounds was designed to 1) systematically assess the nematicidal activity of novel compounds against the egg stage of A. ceylanicum hookworms in culture and 2) define their chemotherapeutic potential in vivo by evaluating their toxicity to human cells. Information gained from these experiments may directly contribute to the development of new drugs for the treatment of human hookworm disease.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ancylostoma / drug effects*
  • Ancylostoma / physiology*
  • Animals
  • Anthelmintics / pharmacology*
  • Drug Evaluation, Preclinical / methods*
  • HeLa Cells
  • High-Throughput Screening Assays / methods*
  • Humans
  • Oviposition / drug effects*

Substances

  • Anthelmintics

Associated data

  • figshare/10.6084/m9.figshare.7961051.v1
  • figshare/10.6084/m9.figshare.7971341.v1

Grants and funding

This work was funded by a private Yale-sponsored grant (Yale Center for Molecular Discovery, High-Throughput Screening Pilot Project Award) to JJV and an NIH/NIAID K22 RSDA awarded to JJV. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.