Objective: To investigate the protective immunity induced by the anti-idiotypic monoclonal antibody NP30 of Schistosoma japonicum in mice.
Methods: An orthogonal table L(16) (4 x 2(12)) was selected as the experimental design. Eight-week-old Kunming outbred mice (male and female) were randomly divided into 16 experimental groups and 2 control groups. Control groups were injected with SP2/0 ascites intraperitoneally. Mice from each group were infected with 100 +/- 2 cercariae of Schistosoma japonicum in the abdominal skin and were sacrificed on the thirtieth day postchallenge. Adult worms were recovered and counted by perfusion of the left ventricle-portal vein. The SP2/0 ascites injected mice were used as controls and the percentage of protection was calculated.
Results: Active immunization of mice with NP30 could produce protection levels ranging from 22.36% to 50.46% depending on the different immunity protocols. The best immunization protocol was established from the results.
Conclusions: Active immunization with NP30 can induce a degree of protection to infection with Schistosoma japonicum cercariae and NP30 is a potential vaccine candidate against Schistosoma japonicum.