FIG. 4.

In vivo growth curves of S. epidermidis 1457 (A and B) and S. aureus RN 6390 (C and D) and their respective ica mutants injected together into the tissue cages of mice at ratios of 1:1 (left panels) and 1:100 (right panels). Numbers of viable counts (CFU/ml) at the time point of infection, at day 2 (2d), and at 8d postinfection are shown. Solid lines represent the wild-type strains, and dotted lines represent the ica mutants. Data from three to eight mice from two experiments were pooled. At 2d, CFU counts of the ica-deficient S. aureus strains were lower than those of the wild-type strains, but this was not the case for S. epidermidis. At 8d, the ica mutants of both S. epidermidis and S. aureus reached significantly lower CFU counts than the corresponding wild-type strains (P < 0.05).