Objectives: The objective of the study is to investigate the role of neurotrophic factors in the DPSCs mediated tissue regeneration.

Methods: Human DPSCs cells were gift from Dr. Songtao Shi, Chair and Professor Department of Anatomy & Cell Biology, University of Pennsylvania School of Dental Medicine DPSCs mRNA was extracted from samples of five different patients, and reverse transcripted into cDNA. Primer sequences were designed with Primer3web online software. Quantitative PCR was performed on the cDNA samples using a 7900HT detection system (Applied Biosystems). All PCR reactions were carried out in triplicate. Quantification of the samples was calculated with the threshold cycle by ΔΔCt method. Immunofluorescent staining images were acquired using a Leica TCS SPE confocal microscope. Scratch assay images were acquired using a Leica DMiL inverted microscope.

Results: The expression of the neurotrophic family members and the corresponding receptors in the DPSC were determined using quantitative PCR. Human DPSCs cells express high level of GDNF family of ligands PSPN and the corresponding receptor GFRa4. Preliminary data indicated that neurotrophic factor PSPN has a dose dependent effect on the DPSCs migration in vitro.

Conclusions: Neurotrophic factors may promote DPSCs regeneration by promoting stem cells migration to the damaged pulp. This work will be important to understand the molecular mechanism of the dental pulp mediated tissue regeneration. The future direction is to investigate the effect of different neurotrophic factors on DPSCs behavior, and the downstream signaling pathways involved in the process.