IL17A and periodontitis: Inactivation of the STAT3 signaling remarkably restored the ability of periodontitis mandibular-derived BM-MSCs in immune suppression, as evidenced by significant reductions in the ratio of Th17 population (Figure 6D and 6E), decreased expression of RORC mRNA (Figure 6F), reduced production of IL-17 (Figure 6G), as well as increased ratio of Treg cells (Figure 6H and Figure 6I), increased FoxP3 mRNA expression and increase secretion of IL-10 (Figure 6J), when compared to the group with vehicle treatment.