ACTIVATION OF TRANSCRIPTION FACTORS AND IL-8 EXPRESSION IN NEUTROPHILS STIMULATED WITH LIPOPOLYSACCHARIDE FROM PORPHYROMONAS-GINGIVALIS

DNA binding activity of NF-kappa B and AP-1 were examined in neutrophi ls stimulated with LPS purified from P. gingivalis, a major pathogenic bacteria of periodontitis lesion. Porphyromonas gingivalis LPS enhanc ed the activity reaching a peak at a concentration of 500 ng/ml in the absence of serum. The NF-kappa B activation stimulated with 10 ng/ml of P. gingivalis LPS was suppressed approximately 44% by treatment of neutrophils with anti-CD14 antibody under the presence of serum. Incre ase in the steady-state IL-8 mRNA level was concomitantly observed by stimulation of neutrophils with 500 ng/ml of P. gingivalis LPS under t he absence of serum. These results indicate that P. gingivalis LPS act ivates NF-kappa B and AP-1 in both serum-dependent and -independent ma nners, followed by increased IL-8 transcription in neutrophils, and su ggested a role for P. gingivalis LPS in IL-8 synthesis by neutrophils in inflamed gingiva and GCF.