Streptococcus mitis cell walls and lipopolysaccharide induce lethality in D-galactosamine-sensitized mice by a tumor necrosis factor-dependent pathway.

Purified cells walls of Streptococcus mitis induced tumor necrosis factor in vitro in whole blood of both lipopolysaccharide (LPS)-sensitive OF1 and LPS-resistant C3H/HeJ mice. They were as effective as heat-killed bacteria in inducing death in both strains of mice sensitized with D-galactosamine. Lethality was suppressed by anti-tumor necrosis factor antibodies. The histopathophysiological findings in mice after challenge with LPS or gram-positive cell walls were indistinguishable.