Figure 4.

The immunogenicity of LT33 in mice. (A) At 6 weeks after the last immunization, the splenic lymphocytes were separated and stimulated with mixed antigens of ESAT6, CFP10, and Rv1738 in vitro for 12h. Flow cytometric analysis of IFN-γ and producing CD4 T cells and CD8 T cells. (B) At 12 weeks after the last immunization, the mice were stimulated with ESAT6 in vivo at 3 days before the mice were euthanized. Then, the splenic lymphocytes were separated and stimulated with ESAT6 in vitro for 12h. Intracellular cytokine staining was analyzed using flow cytometry. (C) Flow cytometric analysis of IFN-γ-producing CD4⁺ T cells by re-stimulation. The above panel is the representing figure. Results are presented as means ± SD, n = 3–4. *p < 0.05, **p < 0.01.