interleukin-8 and dihydrorhodamine-123

Patients with periodontal disease are reported to generate more reactive oxygen species (ROS) than matched controls, suggesting increased inflammatory defense activity. The purpose of this study is to determine whether there are subpopulations of peripheral neutrophils in patients with chronic periodontitis (CP) that generate different levels of intracellular ROS when primed with tumor necrosis factor-α (TNF-α) or the chemokine interleukin-8 (IL-8, CXCL8) compared to controls.. Venous blood was collected from 13 patients with CP despite careful maintenance over 2 to 8 years and from 13 healthy age- and sex-matched controls. Neutrophils were separated from whole blood over a Percoll gradient and then activated via the Fcγ receptor with opsonized Staphylococcus aureus after priming with TNF-α or IL-8. The samples were analyzed by flow cytometry using the fluorescent probe dihydrorhodamine 123. Generation of ROS was measured as the intensity of fluorescence (IFL).. Two subpopulations were found in both patients and controls: one with low and one with high generation of IFL. The subpopulation with high generation of IFL in patients with CP was more responsive to IL-8 (P <0.05) than the same subpopulation in healthy controls. No other differences in generation of ROS or priming effects were found between patients with CP and controls. Generation of ROS was dependent on nicotinamide adenine dinucleotide phosphate oxidase, and the intracellular ROS was primarily the oxygen anion.. Patients with CP had a subpopulation of peripheral neutrophils that were more responsive to IL-8 priming than controls.

Topics: Adult; Aged; C-Reactive Protein; Case-Control Studies; Chronic Periodontitis; Female; Fibrinogen; Fluorescent Dyes; Haptoglobins; Humans; Interleukin-8; Leukocyte Count; Male; Middle Aged; Neutrophils; Periodontal Pocket; Reactive Oxygen Species; Receptors, IgG; Respiratory Burst; Rhodamines; Staphylococcus aureus; Tumor Necrosis Factor-alpha

Cytokines play a major role in the control of inflammatory responses, participate in the regulation of blood phagocyte activities and as such are used for immunomodulatory therapy. In the present study, the influence of IL-10 on human blood phagocyte activity in the presence/absence of IL-6, IL-8 and TNF-alpha was tested in vitro. Our research analyzed the effects of cytokines on the production of reactive oxygen species measured by chemiluminescence and flow cytometry, and on the expression of surface molecules (CD11b, CD15, CD62L, CD31) measured by flow cytometry. IL-10 had no inhibitory effect on reactive oxygen species production and the expression of any examined adhesion molecule by resting or stimulated blood phagocytes within 3 h of incubation. Conversely, TNF-alpha, IL-6, and IL-8 increased reactive oxygen species production and the expression of CD11b and CD15 on both neutrophils and monocytes and decreased the expression of CD62L. These priming effects of the tested pro-inflammatory cytokines were not affected by IL-10. The obtained results suggest that IL-10 does not directly control blood phagocyte activation. These results also provide better information about the contribution of IL-6, IL-8 and TNF-alpha to the regulation of blood phagocyte-mediated inflammatory processes.

Topics: Antigens, CD; CD11b Antigen; Flow Cytometry; Humans; Interleukin-10; Interleukin-6; Interleukin-8; L-Selectin; Leukocytes; Lewis X Antigen; Luminescent Measurements; Monocytes; Neutrophils; Phagocytes; Platelet Endothelial Cell Adhesion Molecule-1; Reactive Oxygen Species; Respiratory Burst; Rhodamines; Tetradecanoylphorbol Acetate; Time Factors; Tumor Necrosis Factor-alpha; Zymosan