Major components of the immune response to hydatid cyst fluid in the host: Echinococcus granulosus-derived immune modulators and the main cytokines that regulate this response. Parasite-derived molecules as AgB, EgTeg, and EgEF-1β/δ could elicit a predominant Th2 activation whereas EgTPx and other HCF components can elicit a concomitant Th1/Th2 cell activation.