Propagation of Toxoplasma gondii in suspension cultures of HeLa cells.

A novel method of Toxoplasma gondii cultivation in suspension cultures has been introduced using silicone-coated glass vessels (working volume 100 ml). The cells were kept in suspension by a magnetic impeller at 75 rpm at a temperature of 37 degrees C. HeLa cells grown on MEM with calf serum were used as host substrate. The HeLa cells were infected with zoites of Toxoplasma gondii virulent P strain. After seven days the host cells were destroyed by the toxoplasmas and the number of zoites was up to 24 x 10(6)/ml.