Increase of gingival matured dendritic cells number in elderly patients with chronic periodontitis

The purpose of this study was to evaluate the inflammatory cell subset proportions in the upper gingival connective tissue, including mature dendritic cells (DC) in elderly and younger patients with generalized chronic periodontitis in order to further understand the effect of aging on gingival inflammatory phenomenon.

Gingival tissue specimens presenting chronic periodontitis from 8 elderly patients aged >75 (test group, group T) and from 8 younger patients aged 50-60 (considered as controls, group C) were analysed by immunohistochemistry using monoclonal antibodies against CD45RB, CD4, CD8, CD19, CD68, DC-SIGN, DC-LAMP molecules. The number of each immunolabelled cells subset was counted using image analysis.

The difference in the number of CD45RB+leucocytes in the upper gingival connective tissue between groups was not significant permitting to use it as reference. As compared to group C, the lymphocyte subsets/CD45RB+leucocytes ratios tended to decrease in group T but the decrease was significant only for CD4+T lymphocytes/CD45RB+cells ratio (p<0.03). On the opposite, the ratios of antigen-presenting cells DC-SIGN+cells/CD45RB+cells and DC-LAMP+cells/CD45RB+cells were significantly increased (p<0.03 and <0.0001, respectively) in group T. Moreover, in group T the DC-LAMP+cells/DC-SIGN+cells ratio was significantly increased (p<0.05) showing an increased number of matured dendritic cells.

During chronic periodontitis in elderly patients, our results show a decrease in the ratio of gingival CD4+lymphocyte subset associated with an increase in the ratios of antigen-presenting cells subsets and more particularly maturated DC-LAMP+dendritic cells.