FIG. 1.

Induction of IL-1β and IL-8 by live and disrupted C. jejuni. MM6 cells (A) and chicken HD11 cells (B) were stimulated for 2 h with 5 × 10⁷ CFU of live or lysed C. jejuni strain 81116 ml⁻¹. As a positive control, 1 μg of LPS from serovar Enteritidis was used. IL-1β and IL-8 transcripts were analyzed by RT-PCR and are presented as the fold increase mRNA levels after stimulation compared to nonstimulated cells. Live Campylobacter induced statistically significant levels of IL-1β and IL-8 mRNA in MM6 cells (P < 0.05), whereas in HD11 cells only the induction of IL-1β was statistically significant (P < 0.05). Stimulation of MM6 and HD11 cells with lysed Campylobacter resulted in significantly higher levels of IL-1β and IL-8 mRNA compared to mock stimulation or stimulation with live bacteria (P < 0.05). Values are means ± the standard errors of the mean (SEM) of three independent experiments.