ABSTRACT
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 /= 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