Antihelminthic Vaccine from Transgenic Rice

Scientists from the University of Tokyo, Gifu University and the Japanese National Institute of Agrobiological Sciences have developed transgenic rice accumulating significant levels of an antihelminthic vaccine. The transgenic rice expresses As16—an antigen protective against the roundworm Ascaris suum—fused with cholera toxin B subunit (CTB). Ascaris roundworms are gastrointestinal nematodes infecting both humans and animals, and the infection is widespread in many parts of the world.

The cholera toxin was used as a mucosal adjuvant for the efficient induction of an immune response. The scientists reported that expression level of the chimeric fusion protein in the endosperm reached 50 μg/g seed. GM rice fed-mice orally administered with nematode eggs had a lower lung worm burden than control mice. The scientists noted that this is the first study that demonstrates how a rice-based oral vaccine can provide protection against a parasite, in an animal model.

The paper is available at http://dx.doi.org/10.1007/s11248-008-9205-4