Alternative Methods of Vaccine Delivery: An Overview of Edible and Intradermal Vaccines

Criscuolo, E.; Caputo, V.; Diotti, R. A.; Sautto, G. A.; Kirchenbaum, G. A.; Clementi, N.

To obtain high quantities of the protein of interest, both nuclear and chloroplast genomes have been successfully engineered. However, the latter option is preferred owing to some advantages including high levels of transgene expression (up to 70% of total soluble proteins (TSP)) [34, 35] , bioencapsulation effect, and regulatory concerns since transgene containment is assured by the fact that plastids are not spread via pollen in most plants. Moreover, incorporation of vaccine antigens into the chloroplast genome would also enable the expression of multiple genes in a single operon, which would be very attractive for multivalent vaccine development. Likewise, this approach may enable the production of vaccines conferring protection against multiple infectious agents and would serve to further reduce costs associated with vaccine production and administration [36] .