Cystoisospora suis merozoite development assay for screening of drug efficacy in vitro.

Cystoisospora suis merozoite development assay for screening of drug efficacy in vitro. Exp Parasitol. 2020 Nov 12;:108035 Authors: Joachim A, Ruttkowski B Abstract Cystoisospora suis is a common diarrheal pathogen of piglets and typically controlled by metaphylactic toltrazuril application. Recently, toltrazuril resistance has been reported in the field; however, both evaluation of toltrazuril efficacy against field isolates and the anticoccidial drug development for pigs is hampered by costs and labor of animal experimentation. Therefore an in vitro merozoite development assay was developed to evaluate the efficacy of compounds against C. suis in vitro. Monolayers of IPEC-1 cells were infected with sporozoites derived from oocysts of defined C. suis laboratory strains and the optimal infection dose as well as concentration, time point and duration of treatment were evaluated by quantitative real-time PCR. Cell cultures were treated with bumped kinase inhibitor (BKI) 1369 at different time points to evaluate the possibility to delineate effects on different developmental stages in vitro during invasion and early infection, and to determine different inhibitory concentrations (IC50, IC95). BKI 1369 had an IC50 of 35 nM and an IC95 of 350 nM. Dose- and duration-dependent efficacy was seen when developing stages were treated with BKI 1369 after infection (days 0-1, 2-3 and 2-5) but not when sporozoites were pre-incubated with B...
Source: Experimental Parasitology - Category: Parasitology Authors: Tags: Exp Parasitol Source Type: research