Abstract: PURPOSE: To detect the effect of DKK1 on biological behaviors of human dental pulp cells exposed to lipopolysaccharide (LPS). METHODS: The dental pulp cells were isolated and cultured by modified enzyme-tissue block method and identified by immunofluorescence staining. The effect of DKK1 on proliferation and migration of human dental pulp cells exposed to LPS were measured by cell counting kit (CCK-8) and Transwell assay. Meanwhile, the effect of DKK1 on differentiation of human dental cells exposed to LPS were studied by alizarin red staining and real-time PCR experiment, statistical analysis was performed using SPSS 20.0 software package. RESULTS: The results of immunofluorescence showed that the cultured cells were in consistent with the mesenchymal stem cells. The result of CCK-8 indicated that DKK1 had no significant effect on proliferation of dental pulp cells exposed to LPS; The result of transwell assay showed that DKK1 significantly promoted the cell migration of dental pulp cells exposed to LPS. The results of Alizarin red staining and real-time PCR revealed that DKK1 could promote cytodifferentiation of dental pulp cells exposed to LPS. CONCLUSIONS: DKK1 promotes the ability of cell migration and cytodifferentiation of LPS treated dental pulp cells, which may be resulted from inhibition of Wnt/β-catenin pathway.

Key words: Dental pulp cells, Lipopolysaccharide, Wnt/β-catenin signaling pathway, Cell migration, Cytodifferentiation