Isolation and immunoelectromicroscopical characterization of Theileria annulata macroschizonts.

Theileria annulata macroschizonts were isolated from bovine lymphoblastoid cells grown in cell culture. To release the parasites, the cells were homogenized under hypotonic conditions. Intact host lymphocyte nuclei were lysed and the resulting chromatin precipitate was degraded by DNase. Host cell fragments were removed by ion-exchange chromatography. As revealed by electron microscopy, the preparations were free of intact host lymphocytes, lymphocyte nuclei and organelles. Antisera raised in rabbits against purified macroschizonts showed a specific reaction with the intracellular parasite in the indirect immunofluorescence test and in immuno-electron microscopy.