Study on the expression of Toll like receptor 2 and interleukin-1 beta induced by Enterococcus faecalis lipoteichoic acid on human periodontal ligament cells

Abstract

To investigate the expression of Toll like receptor 2 (TLR2) and interleukin-1 beta (IL-1 beta) of cultured human periodontal ligament cells (HPDLCs) activated by Enterococcus faecalis (E. faecalis) lipoteichoic acid (LTA). HPDLCs that were obtained from the periodontal tissues of healthy humans were maintained in proper condition. Flow cytometry was used to detect the expression of TLR2 on normal HPDLCs and infectious HPDLCs which were incubated with 0.1, 1, 10 microg mL(-1) E. faecalis LTA for 24 h. IL-1 beta was detected by enzyme linked immunosorbent assay (ELISA) after incubating with LTA of the above concentration for 12, 24 and 48 h or pretreated with TLR2 neutralizing antibody for 1 h and then co-cultured with 1 microg mL(-1) LTA for 24 h. E. faecalis LTA promoted the expression of TLR2 in normal HPDLCs. The difference had statistical significance (P<0.05). IL-1 beta secretion could be detected 12h after stimulation with LTA and increasingly escalate within 48h (P<0.05). TLR2 neutralizing antibody had no evident effect on IL-1 beta generation stimulating by E. faecalis LTA. E. faecalis LTA can increase the expression of TLR2 and IL-1 beta in normal HPDLCs.