A comparative study on the secretion of various cytokines by pulp stem cells at different passages and their neurogenic potential.

Aims. By measuring the extent of cytokines secreted by human dental pulp stem cells (hDPSCs) from passages 2 through 10, the optimal passage of hDPSCs was determined. This offers a potential theoretical basis for the treatment of neurological disorders. Method. After isolation and culture of hDPSCs from human teeth, the morphological features of the cells were observed under an inverted microscope. hDPSCs were identified by their immunophenotypes and their multiple differentiation capability. Cytokine concentrations secreted in the supernatants at passages 2-10 were detected by ELISA. Results. hDPSCs were viewed as fusiform or polygonal in shape, with a bulging cell body, homogenized cytoplasm, and a clear nucleus. Moreover, they could differentiate into neuroblasts in vitro. hDPSCs at passage 3 were positive for CD29 (91.5%), CD73 (94.8%) and CD90 (96.7%), but negative for the hematopoietic markers CD34 (0.13%). ELISA results showed that hDPSCs at passage 3 had the highest secretion levels of vascular endothelial growth factor (VEGF), brain-derived neurotrophic factor (BDNF), and nerve growth factor (NGF), with the highest secretion level of Neurotrophin-3 (NT-3) being at passage 2. Conclusion. hDPSCs have steady biological features of stem cells and exhibit optimal proliferation potential. hDPSCs at different passages have different capacities in the secretion of VEGF, BDNF, NGF, and NT-3. In conclusion cytokines secreted by hDPSCs may prove to be appropriate in the treatment of neurological diseases.