Dental pulp stem cells: function, isolation and applications in regenerative medicine

Human Dental Pulp Stem Cells Differentiate into Oligodendrocyte Progenitors Using the Expression of Olig2 Transcription Factor

The helix-loop-helix transcription factor Olig2 is essential for lineage determination of oligodendrocytes. Differentiation of stem cells into oligodendrocytes and transplanting them is a novel strategy for the repair of different demyelination diseases. Dental pulp stem cells (DPSCs) are of great interest in regenerative medicine due to their potential for repairing damaged tissues. In this study, DPSCs were isolated from human third molars and transfected with the human Olig2 gene as a differentiation inducer for the oligodendrogenic pathway. Following the differentiation procedure, the expression of Sox2, NG2, PDGFRα, Nestin, MBP, Olig2, Oct4, glial fibrillary acidic protein and A2B5 as stage-specific markers was studied by real-time RT-qPCR, immunocytochemistry and Western blot analysis. The cells were transplanted into a mouse model of local sciatic damage by lysolecithin as a model for demyelination. Oligodendrocyte progenitor cells (OPCs) actively remyelinated and recovered the lysolecithin-induced damages in the sciatic nerve as revealed by treadmill exercise, the von Frey filament test and hind paw withdrawal in response to a thermal stimulus. Recovery of behavioral reflexes occurred 2-6 weeks after OPC transplantation. The results demonstrate that the expression of Olig2 in DPSCs reduces the expression of stem cell markers and induces the development of oligodendrocyte progenitors as revealed by the emergence of oligodendrocyte markers. DPSCs could be programmed into oligodendrocyte progenitors and considered as a simple and valuable source for the cell therapy of neurodegenerative diseases.

The regenerative medicine in oral and maxillofacial surgery: the most important innovations in the clinical application of mesenchymal stem cells

Regenerative medicine is an emerging field of biotechnology that combines various aspects of medicine, cell and molecular biology, materials science and bioengineering in order to regenerate, repair or replace tissues. The oral surgery and maxillofacial surgery have a role in the treatment of traumatic or degenerative diseases that lead to a tissue loss: frequently, to rehabilitate these minuses, you should use techniques that have been improved over time. Since 1990, we started with the use of growth factors and platelet concentrates in oral and maxillofacial surgery; in the following period we start to use biomaterials, as well as several type of scaffolds and autologous tissues. The frontier of regenerative medicine nowadays is represented by the mesenchymal stem cells (MSCs): overcoming the ethical problems thanks to the use of mesenchymal stem cells from adult patient, and with the increasingly sophisticated technology to support their manipulation, MSCs are undoubtedly the future of medicine regenerative and they are showing perspectives unimaginable just a few years ago. Most recent studies are aimed to tissues regeneration using MSCs taken from sites that are even more accessible and rich in stem cells: the oral cavity turned out to be an important source of MSCs with the advantage to be easily accessible to the surgeon, thus avoiding to increase the morbidity of the patient. The future is the regeneration of whole organs or biological systems consisting of many different tissues, starting from an initial stem cell line, perhaps using innovative scaffolds together with the nano-engineering of biological tissues.

Dental pulp stem cells differentiation into retinal ganglion-like cells in a three dimensional network

The loss of retinal ganglion cells (RGCs) in majority of retinal degenerative diseases is the first seen pathological event. A lot of studies aim to discover suitable cell sources to replace lost and damaged RGCs. Among them dental pulp stem cells (DPSCs) have a great potential of differentiating into neuronal lineages as well as RGCs. Moreover, three-dimensional (3D) networks and its distribution for growing and differentiation of stem cells as much as possible mimic to native tissue holds great potential in retinal tissue engineering. In this study, we isolate DPSCs from rat incisors and validate them with flow cytometry. Briefly, we differentiated cells using DMEM/F12 containing FGF2, Shh and 0.5% FBS into retinal ganglion-like cells (RGLCs) in two conditions; 3D state in biocompatible fibrin hydrogel and two-dimensional (2D) or conventional culture in polystyrene plates. Immuncytochemical and gene expression analysis revealed the expression of Pax6, Atoh7 and BRN3B increased in 3D fibrin culture compared to 2D conventional culture. In combination, these data demonstrate that using 3D networks can resemble near natural tissue properties for effective generating RGCs which used to treat neurodegenerative diseases such as glaucoma.

The neural crest: a versatile organ system

The neural crest is the name given to the strip of cells at the junction between neural and epidermal ectoderm in neurula-stage vertebrate embryos, which is later brought to the dorsal neural tube as the neural folds elevate. The neural crest is a heterogeneous and multipotent progenitor cell population whose cells undergo EMT then extensively and accurately migrate throughout the embryo. Neural crest cells contribute to nearly every organ system in the body, with derivatives of neuronal, glial, neuroendocrine, pigment, and also mesodermal lineages. This breadth of developmental capacity has led to the neural crest being termed the fourth germ layer. The neural crest has occupied a prominent place in developmental biology, due to its exaggerated migratory morphogenesis and its remarkably wide developmental potential. As such, neural crest cells have become an attractive model for developmental biologists for studying these processes. Problems in neural crest development cause a number of human syndromes and birth defects known collectively as neurocristopathies; these include Treacher Collins syndrome, Hirschsprung disease, and 22q11.2 deletion syndromes. Tumors in the neural crest lineage are also of clinical importance, including the aggressive melanoma and neuroblastoma types. These clinical aspects have drawn attention to the selection or creation of neural crest progenitor cells, particularly of human origin, for studying pathologies of the neural crest at the cellular level, and also for possible cell therapeutics. The versatility of the neural crest lends itself to interlinked research, spanning basic developmental biology, birth defect research, oncology, and stem/progenitor cell biology and therapy.