Increased release of elastase from in vitro activated peripheral neutrophils in patients with adult periodontitis

The main object of this study was to determine if there was a difference between patients with adult periodontitis and healthy controls in the release of elastase. We also wanted to test the release of alpha-1-antitrypsin and lactoferrin from in vitro-activated peripheral neutrophils. A leukocyte-rich preparation from venous blood was made by lysing the red blood cells. The leukocytes were stimulated for 1 h at 37 degrees C with opsonized Staphylococcus aureus and the released elastase was measured with a chromogenic substrate. The release of elastase after stimulation with bacteria was significantly higher in patients than in controls. The amounts of elastase from unstimulated cells, i.e., both released extracellularly and extracted from the pellet, were similar in the 2 groups. However, after stimulation, the amount of elastase in the patient group, but not in the control group, was significantly increased. Similar releases of alpha-1-antitrypsin (A1AT) and lactoferrin were Found in both groups of subjects. In conclusion, this study shows that peripheral neutrophils from patients with adult periodontitis release more active elastase after in vitro activation compared to healthy controls. The release elf A1AT and lactoferrin showed no differences, indicating that the increased elastase activity was not due to a impaired inhibition by A1AT and that the differences in degranulation were limited to the primary granula.