Cytokine Expression of Stem Cells Originating from the Apical Complex and Corona! Pulp of Immature Teeth

Introduction: The aim of this study was to measure and compare the expression levels of cytokines from developing apical complex cells (DACCs) and dental pulp stem cells (DPSCs) of the immature tooth. Methods: DPSC-conditioned medium (CM) and DACCs-CM were obtained from human young teeth, and 174 cytokines secreted from each CM were identified and compared. A cytokine membrane array and enzyme-linked immunosorbent assay were used to measure and compare the expression levels of the cytokines. Immunocytochemistry targeting insulin-like growth factor-1 and neurotrophin-3 was additionally performed. Results: There were statistically significant differences in the expression levels of 25 cytokines: 22 and 3 were expressed more strongly in DPSCs-CM and DACCs-CM, respectively. Odontoblast differentiation-related cytokines were more strongly expressed in DPSCs-CM, while cell-proliferation related cytokines were more strongly expressed in DACCs-CM. Proinflammatory and anti-inflammatory cytokines were predominantly expressed in DPSCs-CM and DACCs-CM, respectively. Conclusions: DPSCs may exert a stronger paracrine effect than DACCs on regeneration of the dentin pulp complex, in terms of odontoblast differentiation.