Toxoplasma gondii in vitro cultivation: economic and efficient mass production

Based on a serum-free and CO,-independent culture of Toxoplasma go&ii in vitro, a simple single arrangement mass production of trophozoites of the highly virulent BK strain of this parasite was developed. Starting simultaneously, lo7 host cells (HEp-2) and 10’ Toxoplasma trophozoites were cultured in one cell-factory@ for 5 days, removing unattached cells, cell remnants and extracellular parasites by flushing daily. Each unit yielded about 0.5X 10’ parasites, which were almost free of any contamination with host cells and cell debris. As extensive manipulation of the cultures were avoided, a simple and reliable method for a mass production of Toxoplasma trophozoites has been developed, distinguishing itself by a low medium consumption and a low work-expenditure.