title: Evaluation of the effects of sulfamethoxazole on Toxoplasma gondii loads and stage conversion in IFN-gamma knockout mice using QC-PCR.
abstract: Toxoplasma gondii abundance with or without sulfamethoxazole treatment was evaluated by quantitative competitive polymerase chain reaction (QC-PCR) assay in various organs of IFN-gamma knockout BALB/c (B/c) mice after peroral infection with the cyst-forming Fukaya strain. T. gondii infection was observed in the brain, skin, tongue, heart, and skeletal muscle of the mice treated with sulfamethoxazole, although the parasite was not observed during the treatment in the mesenteric lymph node, spleen, small intestine or kidney. After discontinuing the therapy, T. gondii reappeared within five days in all organs. Reverse transcriptase (RT)-PCR showed that sulfamethoxazole treatment accelerated the stage conversion of T. gondii from tachyzoites into bradyzoites in the brain, lung, and heart. In contrast, after discontinuing sulfamethoxazole treatment, T. gondii underwent stage conversion from bradyzoites into tachyzoites in these organs. These results indicate that we successfully established an animal model for evaluating chemotherapy regimens in immunocompromised hosts infected with T. gondii.
authors.affiliation: Department of Infection & Host Defense, Graduate School of Medicine, Chiba University, Japan.
authors.forename: Usama S
authors.initials: US
authors.lastname: Belal
authors.forename: Kazumi
authors.initials: K
authors.lastname: Norose
authors.forename: Fumie
authors.initials: F
authors.lastname: Aosai
authors.forename: Hye-Seong
authors.initials: HS
authors.lastname: Mun
authors.forename: Azza K
authors.initials: AK
authors.lastname: Ahmed
authors.forename: Mei
authors.initials: M
authors.lastname: Chen
authors.forename: Rabie M
authors.initials: RM
authors.lastname: Mohamed
authors.forename: Lian-Xun
authors.initials: LX
authors.lastname: Piao
authors.forename: Yoichiro
authors.initials: Y
authors.lastname: Iwakura
authors.forename: Akihiko
authors.initials: A
authors.lastname: Yano
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D007371:Interferon-gamma / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout / Q000469:parasitology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013420:Sulfamethoxazole / Q000494:pharmacology*; D014122:Toxoplasma / Q000187:drug effects* / Q000502:physiology; D014124:Toxoplasmosis, Animal / Q000235:genetics / Q000469:parasitology
chemical_list: D007371:Interferon-gamma; D013420:Sulfamethoxazole