The findings reported herein strongly support the notion that adaptive immunity utilizes autophagy to confer resistance against an intracellular pathogen because: i) CD40 induced entrapment of the parasite by an LC3+ structure; ii) Beclin 1, Atg5 and Atg7 were required for killing of T. gondii within CD40-activated microglia and macrophages; iii) Deficiency of two autophagy proteins, Beclin 1 and Atg7, led to susceptibility to toxoplasmosis while leaving unaffected IFN-γ-induced anti-parasite activity and the induction of an IFN-γ-mediated immune response. This evidence concerns the gene IFNG and toxoplasmosis.