Axenic cultivation of Entamoeba hitolytica.

Entamoeba histolytica (National Institutes of Health strain 200) has been maintained in axenic culture through 50 transfers over a period of 6 months. The medium used is diphasic and contains a cell-free extract of chick embryo which is essential for growth. Inocula of 50,000 amoebas yield 150,000 to 200,000 organisms in 72 hours of incubation at 35 degrees C. An extract prepared from boiled embryos supports growth equally well.