Differentiation potential of stem cells from human dental origin - promise for tissue engineering.

TLDR

Stem cells have been identified in multiple human tissues, including dental structures. The study aimed to isolate primary cultures from dental pulp and periodontal ligament, identify multipotential stem cells, and assess their osteogenic and neuronal differentiation potential. Dental pulp and periodontal ligament were isolated from extracted wisdom teeth, enzymatically dissociated, and cultured, followed by a novel three‑step neurodifferentiation protocol involving epigenetic reprogramming, PKC/PKA activation, and neurotrophic medium. The isolated cultures displayed high proliferation, expressed the STRO‑1 marker, and differentiated into mineralized cells with osteogenic cues or robust neuronal cells using the new protocol, underscoring their potential for dental, bone, and neuroregenerative applications.

Abstract

Recent studies have revealed the existence of stem cells in various human tissues including dental structures. We aimed to establish primary cell cultures from human dental pulp and periodontal ligament, to identify multipotential adult stem cells in these cultures, and to study the differentiation capacity of these cells to osteogenic and to neuronal fates. Dental pulp and the periodontal ligament were isolated from extracted human wisdom teeth. The extracellular matrix was enzymatically degraded to obtain isolated cells for culturing. Both dental pulp and periodontal ligament derived cultures showed high proliferative capacity and contained a cell population expressing the STRO-1 mesenchymal stem cell marker. Osteogenic induction by pharmacological stimulation resulted in mineralized differentiation as shown by Alizarin red staining in both cultures. When already described standard neurodifferentiation protocols were used, cultures exhibited only transient neurodifferentiation followed by either redifferentiation into a fibroblast-like phenotype or massive cell death. Our new three-step neurodifferentiation protocol consisting of (1) epigenetic reprogramming, then (2) simultaneous PKC/PKA activation, followed by (3) incubation in a neurotrophic medium resulted in robust neurodifferentiation in both pulp and periodontal ligament cultures shown by cell morphology, immunocytochemistry and real time PCR for vimentin and neuron-specific enolase. In conclusion, we report the isolation, culture and characterization of stem cell containing cultures from both human dental pulp and periodontal ligament. Furthermore, our data clearly show that both cultures differentiate into mineralized cells or to a neuronal fate in response to appropriate pharmacological stimuli. Therefore, these cells have high potential to serve as resources for tissue engineering not only for dental or bone reconstruction, but also for neuroregenerative treatments.