Toxoplasma gondii infected HFF cells were treated with cucurbitacin E (20,50 and 100 μmol/L) for 1 h, and the egress rate was evaluated statistically. Toxoplasma gondii infected HFF cells were pretreated with Cyto-D and 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetrakis acetoxymethyl ester(BAPTA-AM), followed by 50 μmol/L cucurbitacin E treatment for 1 h and egress determination. The virulence change of egressing Toxoplasma gondii, such parasites were collected and used to re-infect HFF or infect Kunming mice, was analyzed.

Cucurbitacin E could induce the egress of Toxoplasma gondii from host cells, and the egress rate increased with the concentration of cucurbitaci E. Cucurbitacin E-induced ergess depended on the gliding ability of Toxoplasma gondii and intra-parasite calcium. There was no difference between cucurbitacin E-induced egressing parasite and naturally egressing parasite in virulence.

Cucurbitacin E could induce the egress of Toxoplasma gondii from host cells, which provides new direction to study the interactions between Toxoplasma gondii and its host cells.