Genetic transformation of cantaloupe melon (Cucumis melo L.) with the rabies virus glycoprotein gene (PRGSpRgp) and immunisation studies in mice

Abstract

SummaryVaccination is the only means to control rabies, a deadly neuroviral disease with no cure. The use of genetically-altered plants to produce vaccines is gaining importance as it is cost-effective and guarantees freedom from human or animal pathogens. This study reports on Agrobacterium-mediated transformation of Cucumis melo with a rabies virus (strain ERA) glycoprotein gene (PRGSpRgp). The presence of the rabies glycoprotein gene in the DNA of transformed melon leaves was confirmed by PCR amplification. Synthesis of the rabies glycoprotein was detected in transformed cantaloupe fruit by SDS-PAGE and western immunoblotting. Partially purified, recombinant rabies glycoprotein from transformed cantaloupe melon fruit was injected intramuscularly and intraperitoneally into mice, and resulted in the induction of anti-PRGSpRgp antibodies.When these mice were challenged with rabies virus strain ERA they survived infection due to the accumulation of sufficient quantities of anti-rabies glycoprotein antibodies (0.6 – 1.6 IU ml–1). These results demonstrate the accumulation of rabies glycoprotein in edible transgenic cantaloupe melon fruit, which offers the promise of biomedical exploitation.