Probiotic Lactobacillus Strains Stimulate the Inflammatory Response and Activate Human Macrophages

Figure 4

Effect of lactobacillus on the bacterial activity of macrophages against the pathogens S. typhimurium, S. aureus, and E. coli. Human macrophages were infected with (a) S. typhimurium, (b) S. aureus, or (c) E. coli and then incubated for 90 min at 37°C to allow the bacteria to be internalized. External bacteria were then killed by applying gentamicin for 30 min at 37°C. Samples were taken immediately before gentamicin treatment (0 h) and every 120 min thereafter to determine viable counts following Triton X-100 lysis. The results are expressed as CFU per milliliter with means ± SD from no fewer than four separate experiments that were performed in duplicate using macrophages obtained from different human donors. Asterisks indicate a significant difference between conditions ().

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(b)

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