ABSTRACT
Aim: The aim of this study was to analyze the expression level and localization of Toll-like receptor (TLR) 4 in gingival samples of healthy and chronic periodontitis subjects by indirect immunofluorescence technique (IFT). Materials and Methods: In this study, gingival tissue samples were obtained from 25 healthy and 25 periodontitis individuals. The tissues were processed and the initial characterization was done by hematoxylin and eosin staining. The expression and localization of the TLR4 receptor were determined in the epithelial and connective layer cells of the gingival tissue using the indirect IFT. Immunofluorescence images were acquired and quantitative expression of TLRs was analyzed by calculating the percentage of cells showing positive results. Results: We found that the healthy control group exhibited significantly lower values of TLR4 expression in comparison with the periodontitis patients. We also found that in patients with periodontitis the concentration of TLR4 was higher in the epithelium as compared to their expression in connective tissue cells. Conclusions: These data suggested a definite involvement of TLR4 in initiating and progression of an inflammatory response in periodontitis.