[Expression of lipopolysaccharides signal receptors CD14 and TLR4 in human dental pulp tissue and fibroblasts].
OBJECTIVE
To investigate the expression of lipopolysaccharides (LPS) receptors CD14 and TLR4 in normal and inflamed human dental pulp tissue and fibroblasts and to determine the signal transduction pathway of LPS in pulpitis.


METHODS
CD14 and TLR4 expression in healthy and inflammatory pulps was observed by immunohistochemistry. The rates of CD14 and TLR4 positive cells and the mean fluorescence intensity in in vitro cultured pulp fibroblasts before and after being stimulated by LPS.


RESULTS
CD14 and TLR4 were not detected in healthy pulp tissues, but they were strongly positively stained in inflammatory pulps. Ratio of TLR4 positive cells and mean fluorescence intensity produced by the cells stimulated by LPS increased significantly compared with normal pulp cells. However, there were no CD14 expression in human dental pulp cells before and after LPS stimulation.


CONCLUSIONS
This study revealed a significant increase in the expression of CD14 and TLR4 in inflamed human dental pulp tissue. Human dental pulp cells could be induced by LPS to express TLR4, which may play an important role in the process of pulpitis.
Zhang
Chen
C
Department of Operative Dentistry and Endodontics, Faculty of Stamatology, Capital University of Medical Sciences, Beijing 100050, China.
Hou
Ben-xiang
BX
Li
Yu-jing
YJ
Zhang
Min
M
D002478:Cells, Cultured; D003782:Dental Pulp / Q000166:cytology / Q000378:metabolism*; D005347:Fibroblasts / Q000378:metabolism*; D005434:Flow Cytometry; D006801:Humans; D018950:Lipopolysaccharide Receptors / Q000378:metabolism*; D015398:Signal Transduction; D051197:Toll-Like Receptor 4 / Q000378:metabolism*
D018950:Lipopolysaccharide Receptors; C495345:TLR4 protein, human; D051197:Toll-Like Receptor 4