Evaluation of the Effects of Chronic Periodontitis on TLR-2 and TLR-4 Gene Expression in Gingival Tissues

In periodontal diseases, pathogen discrimination by the immune system is an essential factor for triggering host responses. The Toll-like receptor family is responsible for recognition of evolutionarily conserved microbial structures like bacterial lipopolysaccharide (LPS) and activates signaling pathways that eventually lead to immune responses. The aim of the present study was to use real-time PCR to compare TLR-2 and TLR-4 gene expression levels in diseased sites and healthy sites of gingival tissue from periodontitis patients. Gingival biopsies were harvested from healthy sites (BOP- and PD≤3mm) and diseased sites (BOP+ and PD≥5mm) of 20 patients with moderate to severe chronic periodontitis. RNA was extracted from all gingival biopsies. Real-time PCR was performed to evaluate relative quantities of TLR-2 and TLR-4 mRNA. Statistical analyses were done using the Paired Wilcoxon test (2 related sample tests). The relative expression levels of both TLR-2 and TLR-4 were significantly higher at diseased sites (2.41±2.06 and 1.25±1.16) than at healthy sites (0.91±1.04 and 0.41±0.60) (P≤0.01). Periodontal disease can significantly increase TLR-2 and TLR-4 gene expression in gingival tissues.