Peripheral T helper cell profiles during management of periodontitis

Periodontitis has been associated with other systemic diseases with underlying inflammation responsible for the shared link. This study evaluated longitudinal variation in peripheral T helper cells in periodontitis patients undergoing management over 1 year.

Periodontal parameters and peripheral blood mononuclear cells (PBMCs) were collected from 54 periodontitis patients at baseline, and 3-, 6- and 12-months post-treatment and 40 healthy controls. IFN-γ⁺ , IL-4⁺ , IL-17⁺ and Foxp3⁺ and their double-positive expression were identified in CD4⁺ and TCRαβ⁺ cells using flow cytometry. PBMCs were incubated with P. gingivalis, and IFN-γ, IL-4, IL-17 and IL-10 in cell supernatant were measured by ELISA. Cells and cytokines were also assessed based on clinical response to treatment where good (<10% of sites), moderate (10-20%) and poor (>20%) treatment outcome (TxO) groups had probing depths of ≥5 mm at study conclusion.

IFN-γ⁺ cells were lower at baseline, and 3- and 6-months compared to health, whereas Foxp3⁺ cells were increased at 12-months compared to all preceding timepoints and health. The good TxO group showed treatment-related variation in IFN-γ⁺ and Foxp3⁺ cells, whereas the poor TxO group did not. IFN-γ and IL-17 cytokine expression in cell supernatants was significantly lower at baseline compared to health, and IFN-γ and IL-10 showed treatment-related decrease.

This study suggests that IFN-γ⁺ and Foxp3⁺ cells may have a role in the systemic compartment in periodontitis. Periodontal management has local and systemic effects, and thus, assessment and management of periodontitis should form an integral part of overall systemic health.