Molecular farming of Plant Derived Edible Vaccines

Plant Derived Edible Vaccines Abstract Vaccines have been one of the most farreaching and important public health initiatives of the 20 century. Edible vaccine, in particular, might overcome some of the difficult of production, distribution and delivery associated with traditional vaccine. Transgenic potatoes expressing LT-B were found to induce both serum and secretory antibodies when fed to mice, these protective in bacterial toxin assays in vitro. This is the first proof of concept for the edible vaccine. The selection of a plant system for delivery of edible vaccines for human has been addressed. Recognising that it is necessary to express the desired protein in a food that is consumed raw (to avoid denaturation of the candidate vaccine protein), a system to transform banana plant has been developed. The expression of candidate vaccines in banana fruit will be dependant upon identification of suitable specific promoter to drive the desired gene expression. The concept of edible vaccine got impetus after Arntzen and co-workers expressed hepatitis B surface antigen in tobacco. Strategies for expression of foreign genes in high amounts in plants include use of strong and organ specific promoters targeting of the protein into endoplasmic reticulum by incorporating ERtargeting and ER-retention signals, creation of optimized translation start site context as well as alleviation of codons to suit the expression of prokaryotic genes in a plant. Retention of heat labile E.coli enterotoxin in ER of potato by using ER-retention signal has been reported to elevate the expression levels of the recombinant protein. Molecular farming of Plant Derived Edible Vaccines