HYPER-REACTIVE PERIPHERAL NEUTROPHILS IN ADULT PERIODONTITIS - GENERATION OF CHEMILUMINESCENCE AND INTRACELLULAR HYDROGEN-PEROXIDE AFTER IN-VITRO PRIMING AND FC-GAMMA-R-STIMULATION

We have earlier reported a higher Fc gamma-receptor (Fc gamma R)-media ted generation of reactive oxygen species, measured as luminol-enhance d chemiluminescence (CL) from peripheral neutrophils in adult periodon titis patients. The aims of this study were to confirm our previous re sults and to elucidate the mechanism of this phenomenon by measuring C L in parallel with the intracellular production of hydrogen peroxide, after stimulation with opsonized bacteria. To determine whether the hi gher CL was associated with altered responsiveness to priming, the cel ls were preincubated with tumor necrosis factor alpha (TNF alpha) and lipopolysaccharide (LPS). While CL was significantly higher in subject s with periodontitis, there was no difference in hydrogen peroxide pro duction between the patients and the controls, indicating that the hyp erreactivity is related to the generation of other oxygen species than H2O2 and/or to processes in the outer cell membrane. The responsivene ss to priming with LPS on CL was slightly but not significantly higher in the periodontitis group, suggesting that priming could be of value for distinguishing subjects with periodontitis. When assaying intrace llular production of H2O2, TNF alpha and LPS had both a priming and an activating effect. There were no significant differences between the two groups. In conclusion, this study shows a higher Fc gamma R-mediat ed CL of peripheral neutrophils from adult patients with periodontitis , thus confirming our earlier results. The hyperreactivity seems to be related to the outer cell membrane or to oxygen species other than H2 O2.