Correlation between the levels of pro-inflammatory cytokines in serum, tissue and gingival crevicular fluid in patients with chronic periodontitis

Abstract

Several studies have focused on the evaluation of the immunoinflammatory process related to periodontitis to understand the disease etiopathogenesis, its possible influence in the systemic condition as well as to monitor the effects of different therapies. Therefore, the identification and quantification of biomarkers, particularly cytokines, have been performed using different biological sources, especially serum, tissue and gingival crevicular fluid. However, the levels of correlation between the expression/levels of biomarkers in these different biological sources are not clear so far. Therefore, the aim of this study will be to correlate the tissue gene expression and the protein levels of interleukin (IL)-1 beta, IL-6 e tumoral necrosis factor (TNF)- alpha in serum, tissue and gingival crevicular fluid (GCF) of patients with chronic periodontitis. Thirty patients with generalized chronic periodontitis will be included in this study. The subjects will be submitted to tissue and GCF sampling around two teeth indicated to exodontia due to advanced periodontitis as well as to blood sampling. Tissue, GCF and serum samples will be evaluated in relation to the protein levels of IL-1 beta, TNF- alpha e IL-6 by means of the multiplex immunoassay. In addition, a portion of the gingival tissue will be evaluated in relation to the levels of mRNA for these cytokines by means of real time PCR. The statistical analysis will involve correlations (Spearman correlation) between the protein levels of these biomarkers in serum, tissue and GCF and their gene expression in tissue. A significance level of 5% will be set for all analyzes. (AU)