Human dental pulp stem cells (hDPSCs) are some of the most promising stem cell types for regenerative therapies given their ability to grow in the absence of serum and their realistic possibility to be used in autologous grafts. In this review, we describe the particular advantages of hDPSCs for neuroregenerative cell therapies. We thoroughly discuss the knowledge about their embryonic origin and characteristics of their postnatal niche, as well as the current status of cell culture protocols to maximize their multilineage differentiation potential, highlighting some common issues when assessing neuronal differentiation fates of hDPSCs. We also review the recent progress on neuroprotective and immunomodulatory capacity of hDPSCs and their secreted extracellular vesicles, as well as their combination with scaffold materials to improve their functional integration on the injured central nervous system (CNS) and peripheral nervous system (PNS). Finally, we offer some perspectives on the current and possible future applications of hDPSCs in neuroregenerative cell therapies.

Stem cell-based therapies have shown promising results for the regeneration of the nervous system. However, the survival and integration of the stem cells in the neural circuitry is suboptimal and might compromise the therapeutic outcomes of this approach. The development of functional scaffolds capable of actively interacting with stem cells may overcome the current limitations of stem cell-based therapies. In this study, three-dimensional hydrogels based on graphene derivatives and cerium oxide (CeO₂) nanoparticles are presented as prospective supports allowing neural stem cell adhesion, migration and differentiation. The morphological, mechanical and electrical properties of the resulting hydrogels can be finely tuned by controlling several parameters of the self-assembly of graphene oxide sheets, namely the amount of incorporated reducing agent (ascorbic acid) and CeO₂ nanoparticles. The intrinsic properties of the hydrogels, as well as the presence of CeO₂ nanoparticles, clearly influence the cell fate. Thus, stiffer adhesion substrates promote differentiation to glial cell lineages, while softer substrates enhance mature neuronal differentiation. Remarkably, CeO₂ nanoparticle-containing hydrogels support the differentiation of neural stem cells to neuronal, astroglial and oligodendroglial lineage cells, promoting the in vitro generation of nerve tissue grafts that might be employed in neuroregenerative cell therapies.

Bioresorbable nanopatterned scaffolds functionalized with polydopamine (PDA) and graphene oxide (GO) have been shown to promote the differentiation of murine neural stem cells (mNSCs) toward neural and glial lineages. Herein, we aim to evaluate the compatibility of these scaffolds for the culture and differentiation of both human embryonic (hESCs) and induced pluripotent (hiPSCs) stem cells. Our results indicate that PDA and GO scaffolds support the topographic alignment of hESCs and hiPSCs cultures, while preserving their pluripotency characteristics. Upon differentiation, PDA and GO scaffolds guide cell specification toward the neuroectoderm germ layer and the neural crest. This promotes enhanced differentiation into both neural and supportive glial cells of the central nervous system (CNS), as well as Schwann cells of the peripheral nervous system (PNS). Moreover, nanopatterned scaffolds also support the differentiation of hESCs and hiPSCs toward endothelial precursors. These findings establish a novel culture platform that enables combined differentiation pathways, potentially relevant for applications in personalized medicine and regenerative cell therapy.

Stem cell therapy represents a promising strategy for the replacement and functional restoration of damaged neural tissue in neurodegenerative conditions. Human dental pulp stem cells (hDPSCs) have emerged as potential candidates for neuroregeneration due to their ease of isolation, neural crest origin, neurotrophic and anti-inflammatory capacity, and demonstrated ability to differentiate in vitro into neuronal-like cells exhibiting electrophysiological activity. Although the immunomodulatory and neuroprotective properties of hDPSCs have been reported in multiple models of brain disease, their capacity to functionally integrate into host neuronal circuits remain poorly understood. In this study, we have grafted green fluorescent protein (GFP)-transduced, neural preconditioned hDPSCs into the CA1 region of the hippocampus of C57BL/6J mice. One month after transplantation, GFP ⁺ -hDPSCs survived in the brains of non-immunosuppressed mice and remained localized within the grafted area. Notably, the transplanted cells underwent in situ differentiation and exhibited a neuroblast-like phenotype, characterized by positive doublecortin expression and immature neuronal-like electrophysiological properties, like high membrane input resistance, low capacitance, and the ability to generate single action potentials after stimulation. Together, these findings provide the first evidence that hDPSCs can survive and integrate into the hippocampal network of the mouse brain at one-month post graft, supporting their potential use for future therapeutic applications in acute brain lesions and neurodegenerative disorders.