Rabies virus glycoprotein produced in Nicotiana benthamiana is an immunogenic antigen in mice

Rabies remains an infectious disease among humans and animals, and requires the development of an effective vaccine essential to prevent rabies. Advances in molecular biology and biotechnology have led to the development and improvement of many rabies vaccines. Before the third-generation of the vaccine, rabies vaccines were based on the virus itself. Thus, even if effective, these vaccines may not be completely safe, resulting in a strong demand for the development of effective subunit vaccines that do not raise concerns about virus replication and infection in the host. This study investigated the ability of the glycoprotein of the rabies virus to be expressed in tobacco plants (Nicotiana benthamiana) and to induce an immune response in mice. Using a transient transfection, a soluble glycoprotein was successfully expressed in N. benthamiana. Fusing of five histidine residues at the C-terminus enabled the glycoprotein to be easily purified by affinity chromatography. The glycoprotein expressed in the plants was found to be N-glycosylated post-translationally, and the mice immunised with this glycoprotein generated neutralising antibodies against the rabies virus. These results suggest that a glycoprotein produced in the endoplasmic reticulum of N. benthamiana is bioactive, and might be used to generate a subunit vaccine against the rabies virus.