FIG. 1.

Survival of M. smegmatis containing pOLYG or p69 in U-937 cells. As described in Materials and Methods, surviving intracellular bacteria were counted at 3, 24, and 48 h after infection. Data are means ± standard deviations from three independent experiments performed on different days. ∗, P < 0.001 compared to pOLYG at each time point.