Clinical Significance of IL-23 Regulating IL-17A and/or IL-17F Positive Th17 Cells in Chronic Periodontitis

OBJECTIVE: To investigate the expression level and clinical significance of (IL-17A(+) and/or IL-17F(+)) Th17 cells under IL-23 regulation in patients of chronic periodontitis (CP) and healthy controls (HC). MATERIALS AND METHODS: The whole peripheral blood samples were collected from 30 CP patients and 25 healthy controls. Flow cytometry was used to test the (IL-17A(+) and/or IL-17F(+)) Th17 expression level. Recombinant human IL-23 (rhIL-23) was used to detect Th17 differentiation and expansion. Correlation coefficient analysis between Th17 expression level and clinical parameters was analyzed by SPSS software. RESULTS: Flow cytometry results showed that IL-17A(+)IL-17F(-) and IL-17A(-)IL-17F(+) Th17 were both increased in CP group than in HC group (P < 0.01), while, under recombinant human IL-23 (rhIL-23) stimulation, the number of IL-17A(+)IL-17F(-) Th17 cells was significantly increased in both CP and HC groups (P < 0.01). Interestingly, IL-17A(-)IL-17F(+) Th17 cells were only increased in CP group after rhIL-23 stimulation. Additionally, correlation coefficient analysis showed significant correlation between IL-17A(+)IL-17F(-) Th17 cell and attachment loss or probing depth (P < 0.05). CONCLUSIONS: This study indicates that both the IL-17A(+)IL-17F(-) and IL-17A(-)IL-17F(+) Th17 cells may be involved in pathogenesis of periodontitis. The role of these Th17 cells in the disease pathogenesis needs to be further investigated.