IL17A and periodontitis: In addition, Cx3cr1+ iOCs expressed immunosuppressive factors and controlled the immune function of Cx3cr1− iOCs, revealing heterogeneity in OC populations.13 Of note, IL-17A has been shown to be a key inducer of iOC formation.11,135 Several studies have looked for links between DCs and alveolar bone loss associated with periodontitis.