key: cord-0970446-qh2077zo authors: Shrestha, Aruna; Ruttkowski, Bärbel; Greber, Patricia; Whitman, Grant R.; Hulverson, Matthew A.; Choi, Ryan; Michaels, Samantha A.; Ojo, Kayode K.; Van Voorhis, Wesley C.; Joachim, Anja title: Reduced treatment frequencies with bumped kinase inhibitor 1369 are effective against porcine cystoisosporosis date: 2020-08-21 journal: Int J Parasitol Drugs Drug Resist DOI: 10.1016/j.ijpddr.2020.08.005 sha: 227cc1fc8db7a3a68ebf9abb02f4c53c2e32652f doc_id: 970446 cord_uid: qh2077zo Bumped kinase inhibitors (BKIs) are a new class of antiprotozoal drugs that target calcium-dependent protein kinase 1 (CDPK1) in various apicomplexan parasites. A multiple dose regimen of BKI 1369 has been shown to be highly effective against Cystoisospora suis (syn. Isospora suis), the causative agent of neonatal porcine coccidiosis. However, multiple dosing may not be widely applicable in the field. The present study aimed to determine the efficacy of reduced treatment frequencies with BKI 1369 against porcine cystoisosporosis in vitro and in vivo. Pre-incubation of sporozoites with BKI 1369 completely failed to inhibit the infection in vitro unless treatment was prolonged post-infection. Notably, a single treatment of infected cell cultures 2 days post-infection (dpi) resulted in a significant reduction of merozoite replication. In an experimental infection model, treatment of suckling piglets experimentally infected with C. suis 2 and 4 dpi with 20 mg BKI 1369/kg body weight completely suppressed oocyst excretion. A single treatment on the day of infection or 2 dpi suppressed oocyst excretion in 50% and 82% of the piglets and reduced the quantitative excretion in those that shed oocysts by 95.2% and 98.4%, respectively. Moreover, a significant increase in body weight gain and reduced number of diarrhea days were observed in BKI 1369 treated piglets compared to the control piglets, irrespective of time points and frequencies of treatment. Given that reduced treatment frequencies with BKI 1369 are comparable in efficacy to repeated applications without any adverse effects, this could be considered as a practical therapeutic alternative against porcine cystoisosporosis. counting free merozoites 9 days post-infection (dpi) from culture supernatants. Supernatants were collected and free merozoites were counted in pooled samples at 126 9 dpi from quadruplicate wells in C-Chip disposable hemocytometers 127 (NanoEnTek/Roth Lactan, Graz, Austria). All assays included DMSO and no-128 treatment controls in quadruplicate. 129 Study animals 130 Two separate animal experiments were conducted. In each of the experiments, 131 conventionally raised healthy piglets from three crossbred sows (Landrace x Large 132 White) were randomly allocated to four treatment groups (Table 1) . Two weeks 133 before farrowing, the sows were transferred to the animal facility of the Institute of 134 Parasitology, University of Veterinary Medicine Vienna, Austria to acclimatize to the 135 housing conditions. Sows were housed on straw in individual farrowing crates and 136 fed once daily with a commercial feed free of coccidiostats. All rooms were equipped 137 with daylight and ventilation, and a room temperature of 18-20 °C was maintained 138 throughout the trials. The piglets received milk from the sow followed by starter feed 139 from the second week of life. Fresh drinking water was provided ad libitum to the 140 sows and piglets. The first day after the birth of piglets was considered as study day 141 (SD) 1. All piglets were ear-tagged and received 200 mg iron dextran on SD 2 to 142 prevent iron deficiency anemia. The clinical study lasted for 29 days (SD 29) and 143 followed a blinded and randomized experimental block design with the individual 144 piglet as an experimental unit. 145 All the procedures involving animals were approved by the Animal Ethics Committee One piglet from control group was found dead on SD 11. Only those piglets that completed the study were included in the analysis of efficacy. § One piglet in the control group was found dead on SD 20. Only those piglets that completed the study were included in the analysis of efficacy. Control-D 1,2,3 11 10 # 1 x mock* SD 3 Experiment II W 1,2,3 10 10 1 x 20 SD 5 (2 dpi) X 1,2,3 10 10 1 x 10 SD 5 (2 dpi) Y 1,2,3 9 9 1 x 5 SD 5 (2 dpi) Control-Z 1,2,3 10 9 § 1 x mock* SD 5 Bumped kinase inhibitors as therapy for 592 apicomplexan parasitic diseases: lessons learned Autofluorescence microscopy for 594 the detection of nematode eggs and protozoa, in particular Isospora suis, in swine 595 faeces Bumped kinase 597 inhibitor 1294 treats established Toxoplasma gondii infection Statement from Health Canada about the veterinary drug Cystoisospora suis control in Europe is not always 603 effective 607 dependent protein kinase 1 is not required for host cell invasion W A A V P guideline for evaluating the 619 efficacy of anticoccidials in mammals (pigs, dogs, cattle, sheep) Efficacy of sulfonamides and Baycox ® against Isospora suis 622 in experimental infections of suckling piglets Coccidiosis of pigs Companion Animals, and Humans Toxoplasma gondii calcium-dependent protein kinase 1 (TgCDPK1) inhibitors with 630 potent anti-Toxoplasma activity Influence of toltrazuril treatment on 642 parasitological parameters and health performance of piglets in the field -An Austrian 643 experience Calcium-dependent protein kinases as drug 645 targets in Apicomplexan parasites Molecular Approaches toward Targeted Drug Development Effects of experimentally induced Isospora 648 suis infection on morbidity, mortality and weight gains in nursing pigs Distinct signalling pathways control Toxoplasma 651 egress and host-cell invasion Baycox Efficacy of various 655 anticoccidials against experimental porcine neonatal isosporosis Neospora caninum calcium-dependent protein kinase 1 is an 670 effective drug target for neosporosis therapy Clinical measurement of pain, distress and discomfort in pigs The Detetction and Relief of Pain in Animals Cystoisospora suis - A model of mammalian cystoisosporosis Experimentally confirmed toltrazuril resistance in a field isolate of Cystoisospora suis Bumped kinase 683 inhibitor 1369 is effective against Cystoisospora suis in vivo and in vitro Lessons from BKIs: Why it may be 696 hard to get a drug that treats cryptosporidiosis and cystoisosporosis but also 697 toxoplasmosis, sarcocystosis, besnoitiosis and neosporosis Development of an orally available and central nervous system 705 (CNS) penetrant Toxoplasma gondii calcium-dependent protein kinase inhibitor with minimal human ether-a-go-go-related gene (hERG) activity for the 707 treatment of toxoplasmosis Isospora suis in an epithelial cell culture system -An in vitro model for sexual 710 development in coccidia bin CONTRIBUTING.md cord css DEPENDENCIES.md etc GUIDE.md js lib LICENSE log README.md requirements.txt solr_README.md tmp tutorial-04.txt www