Changes in proliferation and osteogenic differentiation of stem cells from deep caries in vitro

It is suggested that dental pulp stem cells are involved in tooth regeneration and play an important role in maintaining pulp homeostasis. Previously, normal dental pulps were more widely used for experimental models than carious dental pulps. The aim of this study was to isolate and culture the dental pulp stem cells from carious and normal teeth and to evaluate stem cell parameters.

Pulp tissues were obtained and dissociated from normal and carious teeth. Single-cell suspensions were seeded into 6-well plates and purified by collecting multiple colonies. Normal dental pulp stem cells (DPSCs) and carious dental pulp stem cells (CDPSCs) were compared for morphologic appearance and for their capacity to differentiate into 3 lineages. Colony-forming and MTT assays, cell cycle analysis, gene expression, and alkaline phosphatase activity were also evaluated.

Stem cells were cultured successfully from normal and carious dental pulps. CDPSCs displayed increased proliferation ability compared with DPSCs. CDPSCs also showed enhanced ALP activity, mineralization ability, and expression of osteogenesis/dentinogenesis-related genes. All cultures differentiated into 3 cell types.

Our data suggest that caries as a local microenvironment should be taken into account when DPSCs are intended to be used for investigations and application. Furthermore, the mechanism of the underlying changes in cell properties requires further study.