Interleukin-6 Receptor Gene rs1800795 Polymorphism and Expression of Interleukin-6 in Gingival Tissue in Patients with Periodontitis

Periodontitis is a multifactorial inflammatory disease. This chronic periodontal disease is caused by a bacterial infection in the gums, which triggers a host inflammatory response. To eliminate the bacterial infection, immune response mechanisms are activated, leading to inflammation and damage to the periodontal tissues. This process involves many cytokines, including IL-6, a cytokine with antibacterial properties. An ongoing bacterial infection in the periodontal tissues leads to its excessive production, which increases inflammation. In this study, we examined <i>IL-6</i> receptor gene rs1800795 polymorphism in patients with periodontitis in comparison with healthy subjects, as well as the correlation between rs1800795 genotypes and clinical parameters. Additionally we examined the expression of <i>IL-6</i> in gingival tissue in patients with periodontitis and control subjects, as well as the correlation between gingival expression of <i>IL-6</i> and clinical parameters. This study included 200 patients with periodontitis and 158 healthy subjects as the control group. Biopsy specimens of gingival tissue in which <i>IL-6</i> expression was detected were taken from 14 patients with periodontitis and 8 controls who had undergone minor surgery. There were no statistically significant differences in the distribution of <i>IL-6</i> rs1800795 genotypes and alleles between patients with periodontitis and control subjects. There were also no statistically significant correlations between <i>IL-6</i> rs1800795 genotypes and clinical parameters in patients with periodontitis. There were no differences in <i>IL-6</i> expression in the gingival tissue between patients with periodontitis and controls. There was also no correlation between <i>IL-6</i> expression in the gingival tissue of patients with periodontitis and clinical parameters. In the control group, <i>IL-6</i> expression in gingival tissue correlated negatively with the approximal plaque index, which reflects the size of bacterial plaques. The results of our study suggest a protective role for IL-6 against bacterial growth in the periodontal tissue. However, it should be noted that several parameters directly or indirectly affect the accumulation of bacterial plaque.