Abstract
Periodontitis is infectious disease by periodontopathic bacteria and characterized by gingival connective tissue loss, periodontal pocket formation and alveolar bone resorption. Unbalance of local immune responses may cause onset and progression of periodontitis. Gingival crevicular fluid (GCF) from the pocket of periodontitis patients contains immuno-competent cells, namely, polymorphonuclear leukocytes, lymphocytes, and macrophages.
Cell surface expression of Fcγ receptor II, III in GCF-polymorphonuclear leukocytes decreased in contrast to increase of complement receptor 3 as compared with those of autologous peripheral blood-polymorphonuclear leukocytes. Transcript levels of Fcγ receptor III and complement receptor 1, 3 significantly decreased. These phenomena may induce impaired phagocytosis of GCF-polymorphonuclear leukocytes and progression of periodontitis.
Regarding for GCF-lymphocytes, decreased T cell/B cell ratio and activated helper T cells and B cells were observed as compared with autologous peripheral blood-lymphocytes. ICAM-1 positive pocket epithelium and LFA-1 expression of GCF-lymphocytes may be related to cell exudation from connective tissue to gingival crevice.
HIV gag protein p24 positive macrophages in GCF increased dramatically in AIDS patients with periodontitis. PCR and RT-PCR of GCF-leukocytes yielded positive signals of p 24, demonstrating viral integration and production. These findings could be considered as a within-mouth source of viral reservoir.
These characteristics of immuno-competent cells in GCF may reflect local immune responses of inflammatory gingival tissues.
