FIG. 8.

Effect of osmotic stress on egress. Parasites were allowed to invade for 1 h and to develop in HFFs for 30 h. At 30 h postinvasion, the normal tissue culture medium was switched to either a hypertonic medium consisting of normal medium plus 20 mM, 40 mM, or 60 mM stachyose (A), a hypotonic medium consisting of either 95% normal medium plus 5% H₂O, 90% normal medium plus 10% H₂O, or 75% normal medium plus 25% H₂O (B), or normal medium as a control (solid bars in both panels). Percent egress is the percentage of lysed vacuoles at 42 h relative to the level at 30 h postinvasion. Data are means from three independent experiments. Each error bar equals 1 standard deviation.