Dental Pulp Stem Cells: Bipotential for Central Nervous System Repair?

Objectives:   This study aims to investigate the potential of DPSCs to differentiate into neurons and oligodendrocytes in vitro.

Methods:   Dental pulp was removed from murine incisors and enzymatically digested to a cellular suspension. Following selection by preferential adherence to fibronectin, heterogeneous and clonal populations were expanded in vitro, and characterised for multipotency markers using RT-PCR and immunocytochemistry techniques. DPSCs were then grown in oligodendrocyte or neural progenitor mediums to induce oligodendrocyte or neuronal differentiation respectively, confirmed by immunostaining.

Results: Isolated pulp cells express various stem cell markers including mesenchymal markers CD90 & SCA1, neural precursor markers nestin & musashi, and oligodendrocyte precursor markers A2B5 & SOX10. Following culture in neuronal-induction medium, DPSCs extend long processes to form networks and co-express Tuj1 and MAP-2. Oligodendrocyte-inducing culture conditions result in DPSCs adopting a highly branched morphology typical of oligodendrocytes combined with expression of Olig2, Myelin Basic Protein (MBP) and CNPase.

Conclusions: Cells expressing markers associated with both neural and oligodendrocyte progenitors can be isolated from the dental pulp. In vitro these cells demonstrate the capacity to differentiate down both neural and oligodendrocytic lineages. The dental pulp may, therefore, provide a suitable alternative source of progenitor cells for repair and regeneration following damage to the central nervous system.  This study is funded by a Royal Society URF award and ERC starting grant to BS (No: 243261)