Research Article

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

Figure 8

Assessment of the humoral response during the piglet experiment. Four groups of 2 piglets were immunized on days 0, 7, and 14 through an intradermal route. Group 1 was injected with E. coli ESAT-6, group 2 with TLE-TBAg-ELP, group 3 with E. coli ESAT-6 and boosted two times with TLE-TBAg-ELP, and group 4 received PBS, as the control. Sera were harvested weekly and diluted ( 1 0 − 2 , 1 0 − 3 , a n d 1 0 − 4 ). The IgG antibody response against the different TB antigens was measured by ELISA (a) and Western blot (b). (a) ELISA analysis of the piglet IgG response on day 28 against E. coli ESAT-6, Ag85B, and plant-expressed TBAg-ELP. Results represent the mean optical densities ( ± SEM, 𝑛 = 2 , each in triplicate). (b) Western blot analysis of the piglet antibody response on day 0 and 28. Lane 1: rabbit antisera, lanes 2 and 6: sera from piglets immunized with E. coli ESAT-6 (group 1), lanes 3 and 7: sera from piglets immunized with TLE-TBAg-ELP (group 2), lanes 4 and 8: sera from piglets sensitized with E. coli ESAT-6 and boosted with TLE-TBAg-ELP (group 3), and lanes 5 and 9: sera from control piglets receiving PBS (group 4).