Immunization of rabbits against Hyalomma anatolicum anatolicum using larval and nymphal extracts

The protective capacity of the crude extracts from larval and nymphal stages of Hyalomma anatolicum anatolicum was examined in the New Zealand white rabbits. The rabbits were randomly divided into 3 groups of five animals. The rabbits in groups 1 and 2 were immunized with crude extracts of larval and nymphal antigens, respectively and group 3 was served as control. Following challenge of each rabbit with 2000 larvae of H. a. anatolicum, engorged nymphs were collected, weighed and then cultured in an incubator. A significant decrease in weight of engorged nymphs was only observed in group 1 that immunized with crude extracts of tick's larvae [P<0.05]. Polypeptide profile of the larval and nymphal extracts was analysed by SDS-PAGE, and antigenic pattern with serum of immunized rabbits was evaluated by Dot and Western blot test. The molecular weight of the fraction of larval extract after SDS-PAGE showed six polypeptide bands as follows: 97, 84, 66, 55, 45 and 36 kDa, and in nymphal extract 13 polypeptide bands of 205, 116, 97, 84, 66, 55, 45, 36, 29, 24 and 20 kDa and two bands between 116 and 205 kDa were found. In Western blotting, positive reaction was only observed with sera of group 1 in the bands with 97, 84 and 66 kDa. It seems that the larval extract of H. a. anatolicum can be used as a source of biological material for isolation of protective antigen

Immunization of lambs with whole body Echinococcus granulosus

We conducted this study to determine the level of immunity after vaccination of lambs with whole body Echinococcus granulosus. To do so, 200 mature E. granulosus parasites, which were kept in 10% formaline for 8 months, were obtained from the Department of Parasitology, School of Veterinary Medicine, Ferdowsi University of Mashhad. The soluble protein of the parasite was prepared. The sample was homogenized in a blender, sonicated on ice and then centrifugated for 15 min at 10,000 g. Final yield was kept at -20°C until used. Eight 4-6-month-old lambs of mixed sex, were divided into 2 equal groups; each lamb in the test group was vaccinated subcutaneously in the neck with 2 ml of the vaccine [1 mg of whole body of E. granulosus protein dissolved in 1 ml of PBS plus 1 ml of Freund's complete adjuvant [FCA]]. The control lambs were vaccinated only with adjuvant in PBS. Lambs were re-vaccinated four weeks after the first vaccination with the same preparation except that FCA was replaced by Freund's incomplete adjuvant [FIA]. Three weeks later, each lamb was administered a challenge infection dose of 2000 protoscolices intraperitoneally and 10 adult E. granulosus. After 7 months, all lambs were killed and examined for hydatid cysts. We found two cysts in the liver and and one in the lung of only one of the vaccinated lambs. The number of cysts in vaccinated lambs were significantly lower than that in the control group [P<0.001]. This means that the protective immunity in lambs with whole body of E. granulosus was approximately 90%