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

• Published in: International journal for parasitology 2002-07, Vol.32 (8), p.1053-1064
• Main Authors: DUBEY, J. P, LINDSAY, D. S, ROSENTHAL, B. M, SREEKUMAR, C, HILL, D. E, SHEN, S. K, KWOK, O. C. H, RICKARD, L. G, BLACK, S. S, RASHMIR-RAVEN, A
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Cats; Cattle; Cell Culture Techniques - methods; Cell Line; Cercopithecus aethiops; Coccidiosis - parasitology; Coccidiosis - transmission; Freezing; Fundamental and applied biological sciences. Psychology; Interferon-gamma - genetics; Interferon-gamma - physiology; Life cycle. Host-agent relationship. Pathogenesis; Liver - parasitology; Lymph Nodes - parasitology; Mice; Mice, Knockout; Microscopy, Electron; Molecular Sequence Data; Monocytes - parasitology; Opossums - parasitology; Protozoa; Sarcocystidae - genetics; Sarcocystidae - growth & development; Sarcocystidae - isolation & purification; Sarcocystidae - ultrastructure; Time Factors
• ISSN: 0020-7519; 1879-0135
• DOI: 10.1016/S0020-7519(02)00060-7

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.