Bradyzoite replication and conversion to tachyzoites in 2D cell culture.

(A) Representative fluorescent images of parasite replication in HFF, Caco-2, and HIEC-6 cells infected with ME49 mCherry brain bradyzoites, either activated by pepsin for 30 min or subjected to mechanical lysis, at 7 days post-infection. Graph shows parasite kinetics of growth in HFF, Caco-2 and HIEC-6 cells for pepsin-activated versus inactivated bradyzoites. (B) Representative fluorescent images of tachyzoite conversion in HFF infected with EGS <i>in vitro</i> differentiated bradyzoites activated by pepsin for 30 min. Conversion and replication were followed up to 4 days post-infection. Top graph shows parasite kinetics of growth in the HFFs cells activated by pepsin for 2 or 30 minutes or inactivated. Bottom graph shows EGS bradyzoite conversion to tachyzoites kinetics in the HFFs cells activated by pepsin for 30 minutes. (PDF)