Development of an in vitro drug sensitivity assay based on newly excysted larvae of Echinostoma caproni

Panic, Gordana and Ingram, Katrin and Keiser, Jennifer. (2013) Development of an in vitro drug sensitivity assay based on newly excysted larvae of Echinostoma caproni. Parasites and Vectors, 6 (237).

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


Official URL: http://edoc.unibas.ch/dok/A6174419

Downloads: Statistics Overview


Echinostomiasis is one of the major food-borne trematodiases and the species Echinostoma caproni serves as a useful model for trematocidal drug discovery. The current in vitro drug sensitivity assay uses adult E. caproni worms that are incubated with candidate drugs and scored microscopically for viability at 72 hrs. The aim of this study was to investigate the use of newly excysted larvae (NEL) of E. caproni for in vitro drug testing, which would be faster, more cost effective and more ethical compared to adult worm assays.; Larvae were obtained by collecting metacercariae from snails and triggering their excystation using the trypsin-bile salt excystation method. Studies concerning various parameters of this chemical transformation process as well as appropriate NEL culturing conditions were carried out and findings evaluated. NEL and adult worms were incubated with praziquantel, tribendimidine, albendazole and quinine and evaluated microscopically 72 hrs post-incubation. In addition, the colorimetric markers resazurin, CellTiter-Glo(R) and Vybrant(R) were tested as an alternative assay read-out method.; The chemical excystation method successfully induced E. caproni metacercariae to excyst at a rate of about 20-60% larvae excysted. NEL remained viable in culture medium for 5--7 days. The results of an in vitro drug assay using NEL mirrored the results of an assay using adult worms incubated with the same drugs. None of the markers could reliably produce signals proportional to NEL viability or cytotoxicity without significant complications.; NEL are adequate for in vitro drug testing. Challenges remain in further improving the excystation yield and the practicability of the assay setup. Resolving these issues could also improve read-outs using colorimetric markers. Using NEL is in alignment with the 3 R rules of the ethical use of laboratory animals and can greatly increase the rate and affordability with which drugs are screened in vitro against this intestinal trematode.
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
Item Type:Article, refereed
Article Subtype:Research Article
Publisher:BioMed Central
Note:Publication type according to Uni Basel Research Database: Journal article
Identification Number:
edoc DOI:
Last Modified:16 Nov 2016 08:34
Deposited On:27 Mar 2014 13:13

Repository Staff Only: item control page