Acute-phase proteins in gingival crevicular fluid during experimentally induced gingivitis

The dynamics of four acute-phase proteins were investigated in gingival crevicular fluid (GCF) during the course of a 21 day experimental gingivitis study. These acute-phase proteins were the protease inhibitors alpha 2-macroglobulin (alpha 2-M) and alpha 1-antitrypsin (alpha 1-AT) and the iron-binding proteins transferrin (TF) and lactoferrin (LF). 6 healthy volunteers ceased all oral hygiene procedures for 3 weeks. GCF was sampled at seven day intervals from two sites per subject by paper strips for 30 s during the experimental gingivitis period and for two additional weeks after the reinstitution of oral hygiene. The mainly serum derived alpha 2-M, alpha 1-AT and TF exhibited very similar dynamics which reflects their common origin in GCF. Their levels increased significantly from baseline and remained high for at least one week after the reinstitution of oral hygiene measures (repeated measures MANOVA; alpha 2-M: p = 0.015; alpha 1-AT: p = 0.012; TF: p = 0.02). This probably reflects increased vascular permeability in the gingivae and, to a lesser degree, local production by gingival inflammatory cells. In contrast to the serum derived acute-phase proteins, the neutrophil derived LF rose significantly from baseline (repeated measures MANOVA; p = 0.001) but dropped rapidly after the reinstitution of oral hygiene measures. This could be because dental plaque was removed and thus neutrophil chemotactic agents in the crevice were decreased.