Signs of the presence of Th17 cells in chronic periodontal disease

Abstract

The aim of this study was to identify the specific markers of T helper 17 (Th17) cells and their variations in people suffering from chronic periodontal disease in comparison with normal control subjects. In 30 patients with periodontitis and 30 normal control subjects, the mRNA expressions of interleukin (IL)-17A and retinoic orphan receptor C2 (RORC2) were measured by quantitative RT-PCR. The protein levels of IL-17A and RORC2 were also evaluated by immunohistochemistry. The levels of these markers were compared between healthy and diseased periodontal tissues by the Mann-Whitney U-test. In periodontal lesions, IL-17A and RORC2 were significantly overexpressed compared with normal tissues. According to our immunohistochemical analysis, the number of IL-17A-positive cells and RORC2-positive cells was significantly greater in periodontal lesions compared with control sites. Moreover, there was a positive correlation between the presence of IL-17A and RORC2 transcript and protein content levels in the gingiva of diseased patients. The results demonstrated a significant increase in the number of some specific markers of Th17 cells in patients suffering from periodontal disease in comparison with normal control subjects.