title: Separation of Isospora (Toxoplasma) gondii cysts and cystozoites from mouse brain tissue by continuous density-gradient centrifugation.
abstract: A simple, quick and reproducible method consisting of density-gradient centrifugation of homogenized infected mouse brain tissue on Percoll is described for the isolation and purification of cysts of Isospora (Toxoplasma) gondii. A 100% recovery of cysts, with 74.2% in a single fraction with a specific gravity of 1.056, was obtained by overlaying homogenates of infected mouse brains on a pre-formed Percoll gradient and centrifugation at low g forces. With this procedure recovery was independent of the age of the cysts. Titration of purified cystozoites showed there to be no loss of infectivity.
mesh_terms: D000818:Animals; D001921:Brain / Q000469:parasitology*; D002499:Centrifugation, Density Gradient; D007549:Isospora / Q000254:growth & development / Q000302:isolation & purification*; D051379:Mice; D010274:Parasitology / Q000379:methods; D011205:Povidone; D012822:Silicon Dioxide
chemical_list: C016039:Percoll; D012822:Silicon Dioxide; D011205:Povidone