S100A8 Polymorphisms and Plasma Calprotectin in Aggressive Periodontitis

Objectives: Calprotectin is a heterodimer of S100A8 and S100A9, and play an important pro-inflammatory role in various inflammatory diseases. Levels of calprotectin in gingival crevicular fluid from diseased sites of periodontal patients were significantly higher than those from healthy sites. Gene polymorphisms of S100A8 might be associated with periodontitis susceptibility. The aim of this study is to investigate the influence of aggressive periodontitis on plasma levels of calprotectin, and relationship between gene polymorphisms of S100A8 and calprotectin levels. Methods: Plasma concentrations of calprotectin were measured in 139 aggressive periodontitis patients and 88 control subjects. Clinical parameters including probing depth, attachment loss and severe sites percent were recorded. S100A8 +445 (A>G) and -581 (A>G) polymorphisms were measured by polymerase chain reaction amplification. Results: Plasma concentrations of calprotectin in aggressive periodontitis patients were significantly higher than those of controls (2.17mg/l vs. 1.72mg/l, respectively, P=0.001), and positively correlated with probing depth, attachment level (P=0.002 and P=0.024, respectively). No significant differences of calprotectin levels were found in aggressive periodontitis patients with different genotypes (+445, P=0.11; -581, P=0.15). Plasma levels of calprotectin were significantly related with probing depth and neutrophil count in aggressive periodontitis patients with AA genotype of these two polymorphisms of S100A8 (+445, P=0.015 and P=0.002; -581, P=0.012 and P=0.001), while patients with GA+GG genotype did not show any relationship between calprotectin levels and all the evaluated variables. Conclusions: These findings suggest that aggressive periodontitis up-regulate plasma levels of calprotectin. Gene polymorphisms of S100A8 may affect the response of aggressive periodontitis patients to periodontal infection, especially response of neutrophil.