Expression of tuberculosis antigen ESAT-6 in Nicotiana tabacum using a potato virus X-based vector

Expression of highly immunogenic tuberculosis proteins in plants using a versatilePotato virus X-based expression system

“…Our findings indicate that ESAT-6 and CFP-10 should be expressed in a fusion form with a larger "carrier" molecule, in order to accumulate the two T-cell antigens for the production of plant-derived TB vaccines. Consistent with this idea, previous attempts to express in Arabidopsis or tobacco plants were achieved by fusing ESAT-6 either to the enterotoxigenic Escherichia coli heat-labile toxin B-subunit, or to PVX coat protein, or to other proteins (Rigano et al, 2004;2006;Zelada et al, 2006;Dorokhov et al, 2007). These tagged proteins are used, not only as a carrier to protect the antigen, but also as an adjuvant or even as antigens to elicit mucosal immunity.…”

An overview of tuberculosis plant-derived vaccines

“…Zelada et al applied a viral vector-based expression approach [73]. This approach has allowed for substantial strides in the field relying on the high replicative capacity of plant viruses [39].…”

“…These levels are substantially higher than those reached by conventional nuclear expression approaches but are very low levels when compared with other viral vector-mediated expression approaches, such as the MagnIcon method. Although virion formation and immunogenic properties of this candidate vaccine have yet to be evaluated, it is proposed that this approach will lead to highly immunogenic products as complex viral structures confer high antigenicity, being efficiently processed by antigen-presenting cells; thus these candidates represent attractive prospects [73]. This platform is also limited to the production of parenteral or intranasal vaccines following a purification process.…”

Developments in Plant-Based Vaccines Against Diseases of Concern in Developing Countries

“…ESAT 6 was also expressed in Nicotiana benthamiana by the Agrobacterium-mediated delivery of TMV-based vectors along with Ag85B, other TB antigen [47]. It was also expressed in Nicotiana tabacum using a potato virus X (PVX)-derived vector as a fusion protein with the capsid protein (CP) [48]. Neither of these two last transiently transformed plants was evaluated as immunogen in animal models.…”