Flow-cytometric analysis of T-lymphocyte subsets after different treatment methods in patients with pericoronitis

Role of TNF-α and Its Receptors in Pericoronitis

The classic stimulus for cellular cytokine production is bacterial lipopolysaccharide (endotoxin). It was therefore hypothesized that tumor necrosis factor-α (TNF-α) may be responsible for pericoronitis. TNF-α and its receptors were detected by immunohistochemical staining in third molar pericoronitis in ten patients and ten healthy control samples. The percentage of TNF-α positive cells was high in pericoronitis (p = 0.0317). TNF receptors TNF-R1 and TNF-R2 were found in macrophage- and fibroblast-like cells, vascular endothelial cells in post-capillary venules, and basal epithelial cells in pericoronitis, but were only weakly expressed in controls. Increased expression of interleukin-1β and vascular cell adhesion molecule-1 was found as a biological indicator of TNF-α ligand-receptor interaction. Explanted tissues acquired destructive potential upon TNF-α stimulation, whereas TNF-α blockers controlled it in inflamed tissues. These findings suggest that, in pericoronitis, inflammatory and resident cells produce and respond to potent pro-inflammatory cytokine TNF-α, with pathogenic and potential therapeutic relevance.