While Engebretson et al. and Mohamed et al. reported significantly higher concentrations of IL-8 in GCF in patients with T2DM+CP as compared to HC+ CP [23,25], IL-8 GCF levels did not correlate with the diabetic status in the recent study by Longo et al. [24]. This evidence concerns the gene CXCL8 and type 2 diabetes mellitus.