[Expression of IL-6 in cyclosporin A-induced gingival overgrowth].

Purpose: To estimate the role of IL-6 in cyclosporin A(CsA)-induced gingival overgrowth(GO) and collect the evidence of pathomechanism for CsA-induced GO.

Methods: Gingival fibroblasts and epithelial cells were treated with CsA of three different concentrations (600ng/mL, 800ng/mL, and 1000ng/mL) with different time (48h, 72h). After cell stretched preparation, the secretion of IL-6 was analyzed by ELISA while expression of IL-6 was analyzed by immunohistochemistry (ABC). SAS 6.0 software package was used for statistical analysis.

Results: The growth speed of gingival epithelial cells in the group treated with CsA was significantly faster than the control group (P<0.05). The IL-6 expression of gingival epithelial cells and fibroblasts had no significance difference, but changed depending on the concentration and treated time with CsA. During the first 24h, there was no significant difference between the experimental and control groups of gingival fibroblasts, while after stimulation of 1000ng/mL CsA for 24h or longer, the secretion of IL-6 in gingival fibroblasts was significantly higher than the control group (P<0.05).

Conclusions: IL-6 is not the main cytokine of gingival epithelial cells, IL-6 in CsA-induced GO probably secreted by the gingival fibroblasts; the effect of CsA on the secretion of IL-6 in the gingival epithelial cells and gingival fibroblasts is associated with the time and concentrations of CsA.