EFFECTS OF LIPOPOLYSACCHARIDES ON HUMAN DENTAL-PULP CELLS

Human dental pulp cells were treated with 1, 10, and 100 mu g/ml of li popolysaccharide (LPS). The effects of treatment were examined by meas urement of the DNA content, protein content, and alkaline phosphatase activity of the cells. LPS samples were purified from Porphyromonas gi ngivalis, Porphyromonas endodontalis, and Fusobacterium nucleatum isol ated from root canals, and Escherichia coli 0111:B4 LPS was used as a positive control. At a concentration of 1 mu g/ml, none of the LPSs ca used any change in the production of DNA or protein, whereas the amoun t of DNA was increased at 10 mu g/ml and inhibited at 100 mu g/ml. Pro tein synthesis was decreased by LPSs at both 10 and 100 mu g/ml. Alkal ine phosphatase activity was not changed at any concentration of LPS t ested.