Figure 6

Intra-colonic administration of IL-1β-producing B. subtilis provokes fever and shock in rabbits. Increase in body temperature in rabbits receiving a single intra-colonic instillation of 1 × 10⁹ live cells of B. subtilis pSM261 (producing IL-1β; ●) or pSM214 (β-lactamase control; ○). As positive control, rabbits received a single intra-colonic administration of 250 μg purified human recombinant IL-1β (■). Data are the mean ± SEM of values of 5 rabbits within a single representative experiment. In the group treated with IL-1β-producing pSM261 bacteria, 2/5 animals died within 30 h of hypotensive shock. From 0.5 to 3 h after treatment, body temperature of pSM216-treated rabbits was significantly higher than that of animals receiving control pSM214 (§p < 0.05;,* p < 0.01).