Saliva and Serum Levels of B-Cell Activating Factors and Tumor Necrosis Factor-α in Patients With Periodontitis

Background: B-lymphocytes play a central and critical role in the adaptive immune response against invading pathogens. This study evaluates saliva and serum levels of APRIL (a proliferation-inducing ligand), B-cell activating factor (BAFF), tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-6, and IL-10 in patients with chronic periodontitis (CP) or aggressive periodontitis (AgP) and periodontally healthy individuals. Methods: Twenty-five patients with AgP, 20 patients with CP, and 20 periodontally healthy individuals were included. Smoking status was recorded, and all individuals were divided into non-smokers and smokers. Saliva and serum samples were collected before clinical periodontal measurements. APRIL, BAFF, TNF-alpha, IL-6, and IL-10 levels in serum and saliva samples were determined by enzyme-linked immunosorbent assay. Statistical analysis was performed using multivariate analysis of variance and bivariate correlation. Results: Serum and saliva levels of TNF-alpha, APRIL, BAFF, IL-6, and IL-10 were similar in CP and AgP groups. Serum levels of TNF-alpha, APRIL, and BAFF and saliva levels of BAFF were significantly higher in periodontitis groups than healthy controls (P < 0.05). Non-smokers with CP or AgP had lower levels of saliva TNF-alpha and APRIL and serum APRIL and IL-6 than smokers with CP or AgP (P < 0.05). Saliva APRIL and serum TNF-alpha and IL-6 levels were significantly higher in healthy smokers than healthy non-smokers (P < 0.05). Clinical periodontal parameters correlated positively with TNF-family cytokines and negatively with IL-10 (P < 0.05). Conclusions: Within the limits of this study, it may be suggested that elevated salivary and serum TNF-alpha, APRIL, and BAFF in patients with periodontitis may contribute to the dominance of B cells in periodontitis lesions. Moreover, higher levels in healthy smokers than non-smoking counterparts may play a role in detrimental effects of smoking on periodontal tissues.