Recombinant antigens cloned from the oncosphere life cycle stage of the cestode parasite Taenia solium (T. solium) have been proven to be effective as vaccines for protecting pigs against infections with T. solium. Previous studies have defined three different host protective oncosphere antigens, TSOL18, TSOL16 and TSOL45. In this study, we evaluated the potential for combining the antigens TSOL16 and TSOL18 as a practical vaccine. Firstly, in a laboratory trial, we compared the immunogenicity of the combined antigens (TSOL16/18) versus the immunogenicity of the antigens separately. Secondly, in a field trial, we tested the ability of the TSOL16/18 vaccine to induce detectable antibody responses in animals living under environmental stress and traditionally reared in areas where T. solium cysticercosis is endemic; and finally, we characterised the immune response of the study population. Pigs of 8-16 weeks of age were vaccinated with 200μg each of TSOL16 and TSOL18, plus 5mg of Quil-A. Specific total IgG, IgG1 and IgG2 antibody responses induced by TSOL16 and TSOL18 were determined with ELISA. The immunogenicity of both antigens was retained in the combined TSOL16/18 vaccine. The combined vaccine TSOL16/18 induced detectable specific anti-TSOL18 antibody responses in 100% (113/113) and specific anti-TSOL16 in 99% (112/113) of the vaccinated animals measured at 2 weeks following the booster vaccination. From the two IgG antibody subtypes analysed we found there was stronger response to IgG2.
Bibliographical noteFunding Information:
The authors thank Juan Chanta for his outstanding support during the field studies, the Cysticercosis Working Group in Peru staff in Tumbes, and the staff of the Veterinary Preventive Medicine Laboratory at the Veterinary Faculty of San Marcos University in Lima, for their technical support and assistance. Funding from the Wellcome Trust (grant number GR075818 ) and the Australian National Health and Medical Research Council (grant numbers 350279 , 628320 , 100354 ) is acknowledged.
- T. solium