Human monocyte response to cementum extracts from periodontally diseased teeth: Effect of conditioning with tetracycline
The purpose of the present study was to test the ability of extracts of cementum from periodontally diseased teeth to induce the secretion of TNF-theta and IL- 1beta by monocytes, to evaluate the role of adsorbed endotoxin in this process, and to test the effect of cementum conditioning with tetracycline on the monocyte response. Extracted, untreated, periodontally diseased (n = 20) and impacted teeth (healthy controls [n = 20]) were used for the experiment. Human monocytes were incubated with varying concentrations of cementum extracts, and TNF-theta and IL-1beta levels in the media were measured. The results showed that while the extracts of healthy cementum had no effect on monocyte secretion, concentrations as low as 0.5 mg/ml of cementum from diseased sites raised the levels of TNFtheta and IL-1beta secretion tenfold. This response was dose related.
Pretreatment of diseased cementum with tetracycline (50 mg/ml) was found to block the secretion of TNF-theta from cementum-stimulated monocytes. Pretreatment of the diseased cementum with 10 mg/ml of tetracycline was no more effective than saline and HCL control, with all treatments reducing cytokine secretion by 80%. The results suggest that extracts from diseased cementum are potent stimulators of monocyte secretion, and that endotoxin, as well as other factors, appears to be involved. [M.R.]
Shapira, L.,Y. Houri, V. Barak, A. Halabi W.A. Soskolne, and A. Stabholz, J Periodont, 67:682, 1996