IL-17 Concentrations in Sera from Aggressive Periodontitis Patients

Objective: The aim of this study was to determine serum levels of IL-17 in subjects with aggressive periodontitis.

Methods: Serum samples were collected from 53 patients with localized aggressive periodontitis (LAgP), 49 patients with generalized aggressive periodontitis (GAgP), and 67 periodontally healthy control subjects (NP). Complete periodontal examinations were carried out, including pocket depth (PD), attachment loss (AL), plaque index (PlI), gingival index (GI), and bleeding index (BI), and demographic data were collected. Serum IL-17 levels were determined by ELISA using a commercially available assay. Differences between subject groups with respect to demographic and clinical variables were determined by Chi-square analyses or ANOVA with Tukey's post hoc test. Associations of IL-17 levels with demographic or clinical variables were determined using regression analyses or ANOVA.

Results: Significant differences were noted in IL-17 serum concentrations between the NP (1.9+1.9 pg/ml), LAgP (7.6+2.2 pg/ml), and GAgP (17.1+2.3 pg/ml) (p<.0001). Levels of Il-17 were positively correlated with pocket depth (p=.005, r2=.17) and attachment loss (p=.008, r2=.17), but not with GI, PlI, or BI. Patient's age (p=.008), but not race or sex, was significantly correlated with IL-17 concentrations. Multiple regression analysis incorporating age as a covariate indicated that diagnostic category remained strongly associated with serum IL-17 (p<.0002).

Conclusions: Serum IL-17 levels are significantly elevated in aggressive periodontitis patients compared to healthy control subjects, indicating that IL-17 could be an important mediator of periodontal inflammation in these destructive diseases.

Supported by R01DE018125 and P60MD002256