PRIMING EFFECT OF PORPHYROMONAS-GINGIVALIS LIPOPOLYSACCHARIDE ON SUPEROXIDE PRODUCTION BY NEUTROPHILS FROM HEALTHY AND RAPIDLY PROGRESSIVE PERIODONTITIS SUBJECTS

PRE-INCUBATION OF NEUTROPHILS from rapidly progressive periodontitis ( RPP) patients with lipopolysaccharide (LPS) extracted from Polphyromon as gingivalis was found to prime the neutrophils for enhanced FMLP-sti mulated superoxide production in a dose-dependent manner. The priming effect of P. gingivalis LPS on neutrophils from control subjects was s canty or without effect at all. Inclusion of human serum in the experi mental priming conditions increased the control and RPP neutrophil res ponse by 2 to 3 fold. Blocking of the CD14 receptor on the neutrophil surface with monoclonal antibody eliminated the priming effect. Furthe rmore, incubation of control neutrophils with P. gingivalis LPS in the presence of serum from RPP patients generated a higher response as co mpared to incubation with control serum. The data suggest that neutrop hil priming described in RPP patients is dependent on a serum factor w hich alters the neutrophil response to priming agents such as LPS.