Lactobacillus rhamnosus GG Activation of Dendritic Cells and Neutrophils Depends on the Dose and Time of Exposure

Figure 1

LGG and BCG induced dose and time dependent effects on DC cytokine production by direct or indirect stimulation via neutrophils. LGG was assessed at 5 : 1, 10 : 1, and 100 : 1 ratios and BCG at 5 : 1 ratios. (a) Production of IL-10, TNF-α, and IL-12p70 after 18 h of continuous coculture of DCs with LGG/BCG (white bar), 2 h of exposure of DCs (black bar) or neutrophil (striped bar) to LGG/BCG, followed by 18 h of bacteria free incubation and 18 h of DC coculture with neutrophils pretreated with LGG/BGC for 2 h (crisscross bar). “” indicates a significant difference () compared to low dose (5 : 1). For BCG “” indicates a significant difference from neutrophils and for TNF-α significance with respect to DC. Data are presented as the mean ± SEM. (b) Neutrophils were prestimulated with low (5 : 1) and high (100 : 1) dose of LGG for 2 h before they were cocultured with DC for 18 h in the presence and absence of a COX-2 inhibitor, NS398 (crisscross bar); COX-2 inhibitor solvent control (black bar); IL-10 neutralizing antibody (IL-10 Ab) (striped bar); and the isotype control for the antibody (double striped bar). The impact on PGE₂, IL-10, and IL-12p70 secretion is shown. “†” indicates a significant difference from the respective controls (). Data are presented as the mean ± SEM.

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