[Mitogenic activity of lipopolysaccharide from Bacteroides intermedius against C3H/HeJ mice spleen cells].

Bacteroides intermedius is one of the periodontal disease generative bacteria. Lipopolysaccharide preparation obtained from B. intermedius ATCC 25611 and ATCC 33563 strains was investigated as to Limulus activity observed with Pyrodic (endotoxin specific) reagent, and mitogenic activity in both normal and tolerant mice induced by Escherichia coli. Limulus activities of all LPS's were nearly similar to that of E. coli. LPS's preparation from B. intermedius were found to be strongly mitogenic for C3H/HeN mice spleen cells, whereas no LPS preparations were mitogenic for thymocytes of BALB/c mice. LPS-nonresponsive C3H/HeJ mice spleen cells were found to good mitogenic responses to LPS's from B. intermedius, as well as LPS from B. gingivalis 381 strain. Polymyxin B had remarkable inhibitory effect on the mitogenicity of LPS's from B. intermedius for C3H/HeN and C3H/HeJ mice spleen cells, also that activity of B. gingivalis LPS was inhibited by polymyxin B. The mitogenicity of the LPS from B. intermedius, as measured in C3H/HeJ mice spleen cells, was considerably resistant to the proteolytic effects of proteinase K.