Expression and Immunogenicity of the Mycobacterial Ag85B/ESAT-6 Antigens Produced in Transgenic Plants by Elastin-Like Peptide Fusion Strategy

Abstract

This study explored a novel system combining plant-based production and the elastin-like peptide (ELP) fusion strategy to produce vaccinal antigens against tuberculosis. Transgenic tobacco plants expressing the mycobacterial antigens Ag85B and ESAT-6 fused to ELP (TBAg-ELP) were generated. Purified TBAg-ELP was obtained by the highly efficient, cost-effective, inverse transition cycling (ICT) method and tested in mice. Furthermore, safety and immunogenicity of the crude tobacco leaf extracts were assessed in piglets. Antibodies recognizing mycobacterial antigens were produced in mice and piglets. A T-cell immune response able to recognize the native mycobacterial antigens was detected in mice. These findings showed that the native Ag85B and ESAT-6 mycobacterial B- and T-cell epitopes were conserved in the plant-expressed TBAg-ELP. This study presents the first results of an efficient plant-expression system, relying on the elastin-like peptide fusion strategy, to produce a safe and immunogenic mycobacterial Ag85B-ESAT-6 fusion protein as a potential vaccine candidate against tuberculosis.

Elastin-like polypeptides: Therapeutic applications for an emerging class of nanomedicines

“…The preferential IgG binding to rSj67 (4.7-fold greater median fluorescence) in the sera of 13 schistosomiasis japonica infected volunteers relative to five uninfected controls was confirmed using bead-based ELISA. Additional diseases for which potential ELP-based vaccines are being explored include tuberculosis [157, 158], influenza[159, 160], and Psittacine beak and feather disease[161]. …”

Chikungunya virus vaccines: Current strategies and prospects for developing plant-made vaccines

“…The efforts on plant-derived vaccines against human diseases using this approach are limited. One of the few studies comprises the M. tuberculosis antigens Ag85B and ESAT-6, which were fused to ELP and expressed in transgenic tobacco [96]. The subcutaneous immunization of mice with either 5 g or 10 g of ICs on days 0, 14, and 28; induced long-lasting humoral immune responses after 84 days.…”

TUBERCULOSIS AND BRUCELLOSIS IN WOOD BISON (BISON BISON ATHABASCAE) IN NORTHERN CANADA: A RENEWED NEED TO DEVELOP OPTIONS FOR FUTURE MANAGEMENT

“…Combined bTB and brucellosis vaccines are more efficacious than either vaccine component alone in cattle (Hu et al 2009a(Hu et al , b, 2010. Similarly, there is progress in modeling different brucellosis vaccine strategies in Yellowstone National Park (Treanor et al 2010;White et al 2011) and in vaccine-delivery mechanisms, including injectable (Denisov et al 2010) and oral plant-based formulations (Musiychuk et al 2005;Rigano et al 2006;Streatfield 2006;Floss et al 2010). Plant-based, purified, subunit vaccines could potentially be applied in forage crops, such as alfalfa or clover, for mass vaccination delivery to freeranging bison herds (Rigano et al 2006).…”