This study describes a simple method for the large-scale isolation of pure Toxoplasma
gondii tachyzoites and bradyzoites. T. gondii tachyzoites were obtained from infected
human foreskin fibroblasts (HFFs) and peritoneal exudates of mice, while tissue cysts
containing bradyzoites were collected from chronically infected mice. Harvested cells
and brain tissues were incubated in Hanks balanced salt solution (HBSS), containing
0.25% trypsin and 0.5% taurodeoxycholic acid (TDC) for 5 min. Subsequent washes
in phosphate buffered saline (PBS) were conducted, and the cell viability of the preparations
was good, as determined by flow cytometry and ability to reinfect HFF cells
and propagate in mice. The purification procedure allowed for a rapid preparation of pure T. gondii tachyzoites and bradyzoites in sufficient quantity that can be used for
downstream procedures. The advantage of the new method is that it is convenient
and inexpensive.