Toxoplasma gondii: Identification and immune response against a group of proteins involved in cellular invasion

► Toxoplasma gondii tachyzoites secreted a group of proteins into the medium. ► These proteins caused cell permeability and facilitated the parasite penetration. ► We immunized infected BALb/C mice with the proteins purified form the medium. ► Immunization increased the survival rate to 80%. ► The purified protein induced a mixed Th1/Th2 response.