Figure 4.

PBMCs (1 × 10⁶/ml) were incubated in either serum-free culture medium (SFM) or 10% Hp-free serum (HFS)-supplemented medium. At the beginning of the culture, 1 μg of LPS and Hp was added, the latter at final concentrations of 0, 50, 250, 500, or 1000 μg/ml. TNF-α production was assessed using ELISA after 72 hr of culture. Results are reported as mean ± SEM of four independent experiments. *P < 0·05, **P < 0·01 versus control.