Platelet-Derived Cytokines in Human Gingival Crevicular Fluid

Objectives: Periodontitis is an oral infection that affects ~50% of the North American population. However, the molecular factors that determine disease progression from gingivitis to periodontitis are not defined. Cytokines secreted by immune cells in the periodontium are detectable in gingival crevicular fluid (GCF), which is readily collected from human subjects. Platelets are cells that control blood clotting but also release growth factors and cytokines that mediate inflammation. The objective of this study is to evaluate the presence of platelet-derived cytokines in the context of inflammatory periodontal disease.
Methods: To evaluate the role of platelets in periodontal disease, we evaluated the presence of platelet factor 4 (PF4), a platelet-specific cytokine, in the gingival crevicular fluid (GCF) of periodontal patients with varying degree of disease severity. Using a micropipette, GCF was collected from healthy (n=25), gingivitis (n=20) and periodontitis sites (n=22). The concentration of PF4 in the GCF was determined by enzyme-linked immunosorbent assay (ELISA).
Results: PF4 was detectable in the GCF in the majority of sites with periodontitis. The mean concentration of PF4 was approximately 20 times higher in the GCF of periodontitis sites compared to healthy sites or gingivitis sites. Conversely, the complete absence of PF4 was observed ~3 times more frequently in health (64%) than in periodontitis (22%).
Conclusions: The prevalence and abundance of PF4 in human GCF is higher in sites with periodontitis, suggesting a possible association between platelet activation and chronic inflammation.