The Immunization of Protoscolices P29 DNA Vaccine on Experimental Cystic Echinococosis in Balb/c Mice

Purpose: Cystic Echinococosis is one of the important parasitic diseases that is considered as a problem economics and health in many parts of the world. Many efforts have been performed for controlling the disease in the world. To reach a reliable vaccine against Cystic Echinococosis is one of the important duty of governments. Several antigen of hydatid cyst for vaccine candidate have been evaluated. In this study, P-29 antigen has been used for this purpose.

Methods: E.g P29 antigen was cloned in Escherichia coli and transfected into the Chinese hamster ovary cell for antigen proliferation and used for vaccination in Balb/c mice. The recombinant antigen E.g-29 was shown using Western blot test. Two dilution of DNA vaccine (pCEgP-29) including 50 µg/100 µl and 100 µg/100 µl were prepared. Twenty four Balb/C male 6-8 week mouse were divided in 4 groups. The groups were included in 2 vaccination groups (pcEg.P29 50 µg/100 µl and 100 µg/100 µl dilution) as immunized groups and 2 groups of plasmid and PBS as control. The mice were injected intramuscularly 3 times with 2 weeks interval. After 3 weeks from last injection, all groups were challenged intraperitonealy with 2000 protoscolices. After 5 months, the mice were euthanized by ketamine/xylasine injection and number, size, and weight of cysts were recorded.

Results: Immunization rate was up to 93% in vaccinated group when compared with the control group.

Conclusion: The results of this study showed that rEg.P29 could be considered as an effective vaccine for controlling of E. granulosus prevalence in intermediated host.