A higher basal secretion from PBMCs of patients with periodontitis compared to healthy controls was in the present study seen for IFN- γ, IL-6, IL-12p70, IL-17, and MCP-1, showing some similarities with the results reported from measurements in gingival crevicular fluid in the aforementioned systematic review and meta-analysis that compared periodontitis patients and healthy controls [21]. This evidence concerns the gene CCL2 and periodontitis.