Fig. 1.

Neutrophil induce a dose-dependent proliferation of A549 cells. A549 cells were co-incubated with isolated neutrophils at given concentrations in the absence or presence of LPS [0.1 µg/ml] in a total volume of 1 ml. 6 h after incubation, the neutrophil-containing supernatant was removed, cells were washed three times, and 500 µl of fresh medium were added containing 75 µl MTS solution. After 2.5 h, absorbance was read at 490 nm. Values are expressed as percentage of MTS activity of A549 cells in the absence of neutrophils, which was set to 100 %. Means and 95 % confidence intervals of at least five independent experiments, each performed in triplicates, are given. Asterisks indicate p < 0.05 for the comparisons to the respective controls