title: Establishment of Besnoitia darlingi from opossums (Didelphis virginiana) in experimental intermediate and definitive hosts, propagation in cell culture, and description of ultrastructural and genetic characteristics.
abstract: Besnoitia darlingi from naturally infected opossums (Didelphis virginiana) from Mississippi, USA, was propagated experimentally in mice, cats, and cell culture and was characterised according to ultrastructural, genetic, and life-history characteristics. Cats fed tissue cysts from opossums shed oocysts with a prepatent period of nine or 11 days. Oocysts, bradyzoites, or tachyzoites were infective to outbred and interferon-gamma gene knockout mice. Tachyzoites were successfully cultivated and maintained in vitro in bovine monocytes and African green monkey cells and revived after an 18-month storage in liquid nitrogen. Schizonts were seen in the small intestinal lamina propria of cats fed experimentally-infected mouse tissues. These schizonts measured up to 45 x 25 microm and contained many merozoites. A few schizonts were present in mesenteric lymph nodes and livers of cats fed tissue cysts. Ultrastructurally, tachyzoites and bradyzoites of B. darlingi were similar to other species of Besnoitia. A close relationship to B. besnoiti and an even closer relationship to B. jellisoni was indicated for B. darlingi on the basis of the small subunit and ITS-1 portions of nuclear ribosomal DNA.
authors.affiliation: Parasite Biology Laboratory, Beltsville Agricultural Research Center, Animal and Natural Resources Institute, United States Department of Agriculture, Building 1001, BARC-East, Beltsville, MD 20705-2350, USA. jdubey@anri.barc.usda.gov
authors.forename: J P
authors.initials: JP
authors.lastname: Dubey
authors.forename: D S
authors.initials: DS
authors.lastname: Lindsay
authors.forename: B M
authors.initials: BM
authors.lastname: Rosenthal
authors.forename: C
authors.initials: C
authors.lastname: Sreekumar
authors.forename: D E
authors.initials: DE
authors.lastname: Hill
authors.forename: S K
authors.initials: SK
authors.lastname: Shen
authors.forename: O C H
authors.initials: OC
authors.lastname: Kwok
authors.forename: L G
authors.initials: LG
authors.lastname: Rickard
authors.forename: S S
authors.initials: SS
authors.lastname: Black
authors.forename: A
authors.initials: A
authors.lastname: Rashmir-Raven
mesh_terms: D000818:Animals; D002415:Cats; D002417:Cattle; D018929:Cell Culture Techniques / Q000379:methods*; D002460:Cell Line; D002522:Chlorocebus aethiops; D003048:Coccidiosis / Q000469:parasitology* / Q000635:transmission*; D005615:Freezing; D007371:Interferon-gamma / Q000235:genetics / Q000502:physiology; D008099:Liver / Q000469:parasitology; D008198:Lymph Nodes / Q000469:parasitology; D051379:Mice; D018345:Mice, Knockout; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D009000:Monocytes / Q000469:parasitology; D009893:Opossums / Q000469:parasitology*; D021745:Sarcocystidae / Q000235:genetics* / Q000254:growth & development / Q000302:isolation & purification / Q000648:ultrastructure*; D013997:Time Factors
chemical_list: D007371:Interferon-gamma