IL17A and periodontitis: Of these, Th1 (IL-12, IFN-γ) and Treg (IL-2 and TGF-β, IL-10 family), have been associated with pleiotropic and anti-inflammatory effects in periodontitis; Th17 (IL-17 and IL-23) and Th2 (IL-4, IL-5, IL-13) also have been associated with pleiotropic effects.