High level expression of surface glycoprotein of rabies virus in tobacco leaves and its immunoprotective activity in mice

Abstract

A synthetic gene coding for the surface glycoprotein (G protein) of rabies virus was strategically designed to achieve high-level expression in transgenic plants. The native signal peptide was replaced by that of the pathogenesis related protein, PR-S of Nicotiana tabacum. An endoplasmic reticulum retention signal was included at C-terminus of the G protein. Tobacco plants were genetically engineered by nuclear transformation. Selected transgenic lines expressed the chimeric G protein at 0.38% of the total soluble leaf protein. Mice immunized intraperitoneally with the G protein purified from tobacco leaf microsomal fraction elicited high level of immune response as compared to the inactivated commercial viral vaccine. The plant-derived G protein induced complete protective immunity in mice against intracerebral lethal challenge with live rabies virus. The results establish that plants can provide a safe and effective production system for the expression of immunoprotective rabies virus surface protein.

Immune response after rabies oral immunization in mice

“…This study showed for the first time that an immune response could be elicited against a PV strain virus using vaccination via oral route in a paste form without creating lesions in the oral mucosa, or forcing oral ingestion of the vaccine. Although no viral challenge was performed, results demonstrated that a paste form of PV vaccine was capable of inducing an antibody immune response, similar to the effect observed in intraduodenal (Atanasiu et al 1982) and intraperitoneal (Ashraf et al 2005) vaccinations.…”

Transgenic Plant Vaccine: A Breakthrough in Immunopharmacotherapeutics

“…The plant-derived G-protein induced complete protective immunity in mice against intracerebral lethal challenge with live rabies virus. The result established that plants can provide a safe and effective production system for the expression of immunoprotective rabies virus surface protein [4].…”

Biotechnological leap in biopharmaceuticals: Current status and challenges ahead

“…The G-protein which is derived from plants for the purpose of immunity is very effective in case of intracerebral lethal challenge occurred by live rabies virus. This lead to the conclusion that the most effective and safe production system to express immunoprotective surface protein related to rabies virus is the imunization through plants [90].…”