Enterococcus faecalis promotes osteoclast differentiation within an osteoblast/osteoclast co-culture system
To investigate the effects of heat-killed Enterococcus faecalis ATCC 29212 and P25RC clinical strain (derived from an obturated root canal with apical periodontitis) on osteoclast differentiation within an osteoblast/osteoclast co-culture system.
Heat-killed E. faecalis significantly increased the proportion of multinucleated osteoclastic cells (MNCs) within the co-culture system. The IL-6 level was significantly increased upon exposure to heat-killed E. faecalis. Gene expression levels of NFATc1 and cathepsin K were significantly up-regulated compared to the untreated control. EphrinB2 and EphB4 expressions at both the mRNA and protein levels were also significantly upregulated compared to the untreated control.
Heat-killed E. faecalis can induce osteoclast differentiation within the osteoblast/osteoclast co-culture system in vitro, possibly through ephrinB2-EphB4 bidirectional signaling.
KeywordsEnterococcus faecalis EphrinB2 EphB4 Multinucleated osteoclastic cells Osteoblasts Osteoclasts Osteoclast differentiation
This work was supported by RFCID/HHSRF HMRF Grant No. 12110772 and Shenzhen Key Laboratory of ENT (No. ZDSYS 201506050935272).
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Conflict of interest
The authors declare that there are no conflicts of interest.
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