FIG. 2.

Vaccination with either BCG or the DNA cocktail resulted in a significant decline in lung and spleen bacterial burdens in CD4^−/− mice (left) and WT mice (right). Organ bacterial CFU values were assessed 28 days after a low-dose aerosol challenge with M. tuberculosis Erdman. The vaccine-induced reduction in bacterial burden is represented as the difference between the CFU values (log₁₀) of naïve controls and immunized mice. For this representative experiment, the CFU values (log₁₀) for the CD4^−/− mice were 8.6 (lung) and 6.6 (spleen) 28 days after the aerogenic infection. For the WT mice, the lung and spleen CFU values were 6.8 and 5.6, respectively.