Figure 1

Inhibition in human mononuclear cells of tumor-necrosis-factor (TNF)-α, induced by lipopolysaccharide (LPS) from Salmonella minnesota Ra (strain R60), by the lead peptide Pep19-2.5 at three different [LPS]:[Pep] weight ratios. Stimulation was performed as described before [34]. Briefly, mononuclear cells (MNC) were isolated from heparinized blood of healthy donors. For stimulation, 200 μl MNC (1 × 10⁶cells) were transferred into each well of a 96-well culture plate. LPS R60 and the LPS:peptide mixtures were preincubated for 30 min at 37°C, and added to the cultures at 20 μl per well and incubated for 4 h at 37°C under 5% CO₂. Supernatants were collected after centrifugation of the culture plates for 10 min at 400xg and stored at -20°C until immunological determination of TNF-α, carried out in a Sandwich ELISA using a monoclonal antibody against TNF. The [LPS]:[Pep19-2.5] 1:1 weight% corresponds to 1.5:1 M/M, the 1:3 weight% to 1:2 M/M, and the 1:10 weight% to 1:6.7 M/M.