Microvesicles and neutrophil aggression factors in the pathogenesis of chronic periodontitis

Background. It is known that the number of polymorphonuclear leukocytes increases with the development of periodontitis. However, their role in the pathogenesis of chronic periodontitis has not been fully defined.

Aim. To study the pathogenetic role of polymorphonuclear leukocytes in the development of chronic periodontitis, realized by microvesicles and aggression factors (metalloproteinases, myeloperoxidase, calprotectin, lipocaine 2).

Material and methods. 30 patients aged 30 to 50 years with a diagnosis of “chronic generalized periodontitis of moderate severity (K05.3)” and no severe somatic pathology were under observation. The comparison group included 20 people with no inflammatory diseases in the oral cavity, comparable with the main group in terms of gender, age, nationality, and the presence of bad habits. Using a standard set of indices, the state of periodontal tissues was assessed, and all examined patients underwent X-ray examination. In the oral fluid of the examined, the total number of microvesicles and their phenotype, the concentration of matrix metalloproteinases-2 and -9, myeloperoxidase, calprotectin, lipocaine 2 were determined. The parameters were determined using a flow cytometer. Descriptive statistics are represented by the median and interquartile range (25th and 75th percentiles). Two independent sample sets were compared using the Mann–Whitney test. Correlation analysis was carried out according to the Spearman method.

Results. The total number of microvesicles in the oral fluid in patients with chronic periodontitis was 11 times higher than in healthy volunteers (p=0.00001). More than a third of them had neutrophil markers. The levels of neutrophil aggression factors were also higher in patients with periodontitis and correlated with the value of the periodontal index, the depth of the periodontal pocket, bleeding index, indicators of periodontal health. Thus, a strong positive relationship was found between the total number of microvesicles and the value of the periodontal index (r=0.675), the depth of the periodontal pocket (r=0.763), the bleeding index (r=0.704); the number of neutrophilic microvesicles and indicators of periodontal health — r=0.816, r=0.837 and r=0.776, respectively. The content of metalloproteinase-2 correlated with the depth of the periodontal pocket (r=0.754), bleeding index (r=0.811), papillary-marginal-alveolar index (r=0.675).

Conclusion. Neutrophils contribute to the pathogenesis of chronic periodontitis through the secretion of aggression factors: metalloproteinases, myeloperoxidase, calprotectin, lipocaine 2, and microvesicles.