FIG. 3.

Translocation of wild-type S. enterica to the intestinal submucosa with and without pretreatment of intestine with sterile bacterial extract. Ligated intestinal loops were injected with sterile extracts (equivalent of 0.2 μg [dry weight]) of serovar Typhi, which triggers CFTR redistribution, or with negative control extracts of E. coli, which does not trigger CFTR redistribution. After incubation with extract, 2 × 10⁴ CFU of live serovar Typhi strain Ty2 (A) or serovar Typhimurium strain LT2 (B) was injected into the intestinal lumen, and the number of bacteria was determined 2 h later by antibiotic treatment to kill extracellular/nontranslocated bacteria. Columns indicate means of seven replicate samples, and error bars indicate the standard errors. ∗, significantly different from “no extract” by ANOVA and Fisher PLSD (P = 0.01).