The capacity of lipopolysaccharides from bacteroides, fusobacterium and veillonella to produce skin inflammation and the local and generalized Shwartzman reaction in rabbits

Purified lipopolysaccharides (LPS) from strains of Bacteroides, Fusobacterium and Veillonella were tested for endotoxic activity, utilizing the primary skin reaction and the Shwartzman phenomena in rabbits. Comparisons were made to Salmonella LPS. Each LPS preparation produced the primary skin reaction in a typical dose‐response fashion. Skin sites injected with 400 μg of Fusobacterium LPS often produced necrotic lesions. In the comparisons made between the skin lesion doses (SLD50) of the Veitlonella LPS and the Salmonella LPS, the difference was either non‐significant or the Salmonella LPS was only slightly more active (P <0.02). LPS from the Fusobacterium and the Bacteroides were significantly less toxic than the Salmonella LPS (P <0.005). All LPS preparations did prepare the skin for the local and the specific organs for the generalized Shwartzman reaction. The toxicity of the Bacteroides LPS was, however, very low in the local reaction (P <0.005). For all LPS preparations the sensitivity of the primary skin test (SLD50) was superior to the local Schwartzman reaction (SPD50) (P <0.005). Twenty‐four hours after challenge for the generalized Shwartzman reaction, extensive fibrin thrombi in the capillaries of the renal glomeruli were found, as well as thrombi containing necrotic blood cells, both in the veins of the liver and in the arteries of the lungs. The high endotoxic activity of the Fusobacterium and the Veillonella LPS may reflect a similarity between their lipid A and that of the Salmonella LPS.