Role of lipopolysaccharide in the production of plasma cell tumors in mice given mineral oil injections.

The lipopolysaccharide (LPS) content of peritoneal fluids of BALB/c mice given mineral oil injections and of normal mice was measured. Peritoneal fluids were passed through DEAE-Bio-Gel columns to remove an inhibitor to the Limulus amebocyte lysate reaction and then were assayed for LPS by a spectrophotometric Limulus amebocyte lysate test. A highly significant difference between control animals and animals given mineral oil injections was found. A clear correlation between LPS concentration and time after first oil injection was shown. P-200 gel chromatography and heat stability of the active material were consistent with the behavior of LPS. The possible role of LPS in the pathogenesis of plasma cell tumor is discussed.