Development of a hookworm egg hatching assay to determine the ovicidal effects of anthelminthics

Easland, E. and Biendl, S. and Keiser, J.. (2023) Development of a hookworm egg hatching assay to determine the ovicidal effects of anthelminthics. Parasit Vectors, 16. p. 157.

[img] PDF - Published Version
Available under License CC BY (Attribution).


Official URL: https://edoc.unibas.ch/94877/

Downloads: Statistics Overview


BACKGROUND: Few anthelminthics are currently available, manifesting the urgent need for new treatment options. In vitro profiling of current anthelminthics against larval and adult stage helminths displayed varying effects on closely related worm species and between life stages of the same species. Conversely, limited research has been performed on the egg stage of human hookworms, and the effects of investigational compounds on the egg stage are not routinely assessed. METHODS: We profiled the development and hatching of Heligmosomoides polygyrus, Ancylostoma duodenale and Necator americanus eggs isolated from rodent faeces in liquid media with various nutrient levels, osmolar concentrations, and acidities in dependence on incubation temperature and light exposure. Incubation conditions were optimised to allow the study of drug effect on immature and embryonated eggs. We analysed concentration-effect relationships of commercially available anthelminthics over 72 h. RESULTS: Rapid embryonation and hatching were observed at room temperature with and without light exposure without nutrient supplementation in a wide range of acidities. Hookworms hatched optimally at room temperature in PBS achieving > 75% hatching over 34 h. Developmental delays were seen when eggs were stored at 4 degrees C with no effect on viability. Similar delays were also seen with increased osmolar concentrations resulting in decreased viability. Benzimidazole anthelminthics effectively reduced the viability and prevented hatching of hookworm eggs, with albendazole and thiabendazole eliciting particularly potent effects at EC(50) values below 1 microM. Macrolide anthelminthics as well as emodepside, oxantel pamoate, and pyrantel pamoate were inactive while monepantel, levamisole, and tribendimidine displayed varied potencies among the hookworm species. CONCLUSION: The presented egg-hatching assay will complement ongoing anthelminthic drug discovery and allow a full characterisation of drug activity against all life stages. In the development and application of the egg-hatching assay, good accordance was observed between the three hookworm species evaluated. Marketed anthelminthics show differences of drug action compared to larval and adult stages highlighting the importance of profiling drug activity against all life stages.
Faculties and Departments:09 Associated Institutions > Swiss Tropical and Public Health Institute (Swiss TPH)
09 Associated Institutions > Swiss Tropical and Public Health Institute (Swiss TPH) > Department of Medical Parasitology and Infection Biology (MPI) > Helminth Drug Development (Keiser)
UniBasel Contributors:Keiser, Jennifer and Easland, Erin and Biendl, Stefan
Item Type:Article, refereed
Article Subtype:Research Article
ISSN:1756-3305 (Electronic)1756-3305 (Linking)
Note:Publication type according to Uni Basel Research Database: Journal article
Related URLs:
Identification Number:
edoc DOI:
Last Modified:07 Jun 2023 06:32
Deposited On:07 Jun 2023 06:32

Repository Staff Only: item control page