The tachyzoites of NC-1 isolate were cultured
on a 24-h-old monolayer of Vero cell line and maintained
in DMEM Medium (Sigma Co., USA) supplemented with 2% fetal
calf serum, penicillin/ml (10,000 U), streptomycin/ml (100 lg)
and streptomycin (25 lg) (Invitrogen, USA) at 37 C with 5% CO2