FIG. 2.

TNF-α induction by S. aureus strains (A) and synthetic MDPs (B). (A) Increasing numbers of S. aureus wild-type (gray bars) or femC mutant bacteria (white bars) were incubated with whole human blood, and TNF-α levels were determined. (B) MDP(iQ) (gray bars) or MDP(E) (white bars) was incubated with whole human blood, and TNF-α levels were determined. The means and standard errors of the means (error bars) of four independent experiments, run in duplicates, are shown. The small differences between the strains in panel A are not significant as calculated by Student's t test.