Peripheral PMN cells in juvenile periodontitis. Increased release of elastase and of oxygen radicals after stimulation with opsonized bacteria.

In 12 patients with juvenile periodontitis (JP), stimulation of peripheral polymorphonuclear neutrophils (PMN) by opsonized bacteria showed increased release of free oxygen radicals and of elastase activity in relation to that of pair-matched healthy controls. The elastase increase was not associated with higher intracellular content of elastase, since the measurement of homogenized PMN cells did not differ between the patient group and the control group; nor did the spontaneous elastase activity of nonstimulated cells differ. Release of elastase by contaminating lymphocytes and platelets could be excluded, since no elastase activity from these cells or interference by these cells could be demonstrated in the assay system used. When formyl-methionyl-leucyl-phenylalanine was used as a stimulant, the chemiluminescence in the patient PMN cells did not differ with statistical significance from their pair-matched controls. The increased release of free oxygen radicals and of elastase seems to be a characteristic of the PMN cells in juvenile periodontitis, indicating hyperactive cells with possible pathogenic effects.