FIG. 4.

T-cell responses of (a) spleens and (b) MLNs. At 40 days after Mycobacterium challenge, mice were sacrificed and the amounts of IFN-γ in the supernatants from cultures of lymphocytes from spleens and MLNs stimulated with ConA or ESAT-6 were examined by ELISA. Groups 2 to 5 were challenged with 10⁶ CFU of virulent M. bovis. Group 1, naïve mice; group 2, nonvaccinated challenged mice; group 3, mice immunized with wt PR8; group 4, BCG-vaccinated mice; group 5, mice vaccinated twice with Flu/ESAT-6 vectors (H1N1-H3N2). Error bars indicate standard errors of the means.