Abstract: Objective To study the proliferation of Toxoplasma gondii RH strain tachyzoites in human foreskin fibroblast （HFF） cells and HeLa cells. Methods HFF cells and HeLa cells were cultured in 35 mm cell culture dishes with glass cover slip. Confluent cells were co-cultured with tachyzoites which purified by 3 μm filter membrane. At 0.5, 1 , 2, 4, 8, 12, 24, 36, 48, 72, and 96 h after co-culture, the invasion of tachyzoites into the cells and proliferation in cells were observed with Giemsa staining. Results In 4 h after co-culture, there were dozens of T.gondii tachyzoites in the HFF cells. At 24 h many pseudocysts emerged. At 72 h most of the cells were destroyed by tachyzoites. While cultured in HeLa cells for 8 h, there were only 3-5 tachyzoites in one cell, and pseudocysts emerged at 48 h. At 96 h after co-culture, most cells were destroyed. Conclusion T. gondii tachyzoites can be cultured in HFF cells and HeLa cells. The proliferation of tachyzoites in HFF cells was quicker than that in HeLa cells.

Key words: Toxoplasma gondii, Tachyzoite, In vitro culture, HFF cell, HeLa cell