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Determination of Chemical Inhibitor Efficiency against Intracellular Toxoplasma Gondii Growth Using a Luciferase-Based Growth Assay
Published on: April 29, 2020
Induction of sulfadiazine resistance in vitro in Toxoplasma gondii
C Doliwa1, S Escotte-Binet, D Aubert
1Laboratoire de Parasitologie-Mycologie, EA 3800, SFR CAP-Santé FED 4231, Université de Reims Champagne-Ardenne, 51 rue Cognacq-Jay, 51095 Reims Cedex, France. christelle.doliwa@univ-reims.fr
Abstract:
We induced sulfadiazine resistance in two sulfadiazine sensitive strains of Toxoplasma gondii, RH (Type I) and ME-49 (Type II) in vitro by using drug pressure. At first, sulfadiazine susceptibility of the two sensitive strains and two naturally resistant strains of T. gondii was evaluated on Vero cells using an enzyme-linked immunosorbent assay (ELISA). The IC(50) values of sulfadiazine were 77 μg/mL for RH, 51 μg/mL for ME-49 and higher than 1000 μg/mL for the two natural resistant strains. Secondly, induced resistance of the strains by gradually increase sulfadiazine concentration was verified by this test, which resulted IC(50) values at higher than 1000 μg/mL. In conclusion we developed in vitro two sulfadiazine resistant strains called RH-R(SDZ) and ME-49-R(SDZ). These strains resistant to sulfadiazine would be useful to characterize resistance mechanisms to sulfadiazine.

