FIG. 1.

Elimination of internalized FimH⁺ or FimH⁻ E. coli by resident BALB/c peritoneal macrophages when λ (A) or gentamicin (B) was used as an extracellular killing agent. The FimH⁺ strains were mixed (1:1) with the FimH⁻ strains and incubated with macrophages. See the text and Table 1, footnotes a to c, for descriptions of the specific bacterial strains employed and the curve parameters compared. Values on the y axis indicate the percentage of internalized bacteria surviving at the times indicated along the x axis. One hundred percent defines that population of macrophage-bound bacteria that survived the 30-min treatment with the extracellular agent. The values shown are averages of four experiments, each performed in duplicate. Error bars denote standard errors of the means. The time points denoted are approximate to allow values from separate experiments to be averaged.