FIG. 2.

An sciS mutant is more numerous in J774 macrophages at 24 h postinfection. These images are representative fields from experiments performed at two separate MOIs. (A and B) Macrophages were infected on glass coverslips in 6-well plates for 24 h at an MOI of 80 and stained with DAPI (DNA stain; blue). (C and D) Macrophages were infected on glass coverslips in 6-well plates for 24 h at an MOI of 10 and stained with DAPI and FM4-64 (membrane stain; red). Macrophages were infected with 14028 (A and C) and ΔsciS (B and D). (E) The average number of bacteria per infected cell for 10 individual fields (P < 0.01, Student's t test). Data from the graph in panel E represent results from three separate experiments. w/t, wild type.