Protective Immunity in Mice with Whole Body of Echinococcus granulosus

Despite the establishment of extensive and successful control programmes in some countries or regions, Echinococcus granulosus still has a very wide geographical distribution. Mature E. granulosus (n = 120) obtained from Parasitology Department, School of Veterinary Medicine, Ferdowsi University of Mashhad (Iran). Soluble protein of whole body of parasite was prepared by freeze-thawing in liquid nitrogen and at 42ºC for three times. The sample was homogenized in a blender, sonicated at 110 V, 170 W for 3 times for 15 s each and then centrifuged at 10,000 ×g for 15 min. Final yield was kept in -20ºC. Ten mice were randomly divided into 2 groups of 5. Each mouse in test group was vaccinated subcutaneously with 100 µg (100 µl) of whole body of E. granulosus plus 100 µl of Freund’s complete adjuvant (FCA), respectively. Mice in control group were vaccinated with adjuvant in PBS. Second vaccination was conducted after four weeks with the same preparation except that FCA was replaced by Freund’s incomplete adjuvant (FIA). Three weeks after the second vaccination, each mouse was challenged with 2000 protoscolices, intraperitoneally. Mouse autopsy was carried out eight months post challenge. Our results show that none of the vaccinated mice with the whole body of E. granulosus had cysts that indicate 100% protective immunity.