Dental follicle stem cells and tissue engineering

Proteomics approaches in the identification of molecular signatures of mesenchymal stem cells

Mesenchymal stem cells (MSCs) are undifferentiated, multi-potent stem cells with the ability to renew. They can differentiate into many types of terminal cells, such as osteoblasts, chondrocytes, adipocytes, myocytes, and neurons. These cells have been applied in tissue engineering as the main cell type to regenerate new tissues. However, a number of issues remain concerning the use of MSCs, such as cell surface markers, the determining factors responsible for their differentiation to terminal cells, and the mechanisms whereby growth factors stimulate MSCs. In this chapter, we will discuss how proteomic techniques have contributed to our current knowledge and how they can be used to address issues currently facing MSC research. The application of proteomics has led to the identification of a special pattern of cell surface protein expression of MSCs. The technique has also contributed to the study of a regulatory network of MSC differentiation to terminal differentiated cells, including osteocytes, chondrocytes, adipocytes, neurons, cardiomyocytes, hepatocytes, and pancreatic islet cells. It has also helped elucidate mechanisms for growth factor-stimulated differentiation of MSCs. Proteomics can, however, not reveal the accurate role of a special pathway and must therefore be combined with other approaches for this purpose. A new generation of proteomic techniques have recently been developed, which will enable a more comprehensive study of MSCs.

β-tricalcium-phosphate stimulates the differentiation of dental follicle cells

The use of dental progenitor cells is a straightforward strategy for regenerative dentistry. For example a cell based therapy with dental follicle cells (DFCs) could be a novel therapeutic strategy for the regeneration of oral tissues in the future. For the regeneration of large bone defects for example dental progenitor cells have to be combined with bone substitutes as scaffolds. This study therefore investigated cell attachment (scanning electron microscopy), cell vitality/proliferation (WST-1 assay) and cell differentiation (under in vitro conditions) of human DFCs on synthetic β-tricalcium phosphate (TCP). DFCs showed considerable cell attachment and proliferation on TCP. Moreover, TCP stimulates osteogenic differentiation in comparison to DFCs with a standard protocol. Here, for example, the osteoblast marker bone sialoprotein (BSP) was highly expressed on TCP, but almost absent in differentiated DFCs without TCP. In conclusion, our study shows that TCP is an excellent scaffold for DFCs for oral tissue regeneration.