Veronica R. Fortino

Progress of mesenchymal stem cell therapy for neural and retinal diseases

Complex circuitry and limited regenerative power make central nervous system (CNS) disorders the most challenging and difficult for functional repair. With elusive disease mechanisms, traditional surgical and medical interventions merely slow down the progression of the neurodegenerative diseases. However, the number of neurons still diminishes in many patients. Recently, stem cell therapy has been proposed as a viable option. Mesenchymal stem cells (MSCs), a widely-studied human adult stem cell population, have been discovered for more than 20 years. MSCs have been found all over the body and can be conveniently obtained from different accessible tissues: bone marrow, blood, and adipose and dental tissue. MSCs have high proliferative and differentiation abilities, providing an inexhaustible source of neurons and glia for cell replacement therapy. Moreover, MSCs also show neuroprotective effects without any genetic modification or reprogramming. In addition, the extraordinary immunomodulatory properties of MSCs enable autologous and heterologous transplantation. These qualities heighten the clinical applicability of MSCs when dealing with the pathologies of CNS disorders. Here, we summarize the latest progress of MSC experimental research as well as human clinical trials for neural and retinal diseases. This review article will focus on multiple sclerosis, spinal cord injury, autism, glaucoma, retinitis pigmentosa and age-related macular degeneration.

Neurogenesis of neural crest-derived periodontal ligament stem cells by EGF and bFGF

Neuroregenerative medicine is an ever‐growing field in which regeneration of lost cells/tissues due to a neurodegenerative disease is the ultimate goal. With the scarcity of available replacement alternatives, stem cells provide an attractive source for regenerating neural tissue. While many stem cell sources exist, including: mesenchymal stem cells, embryonic stem cells, and induced pluripotent stem cells, the limited cellular potency, technical difficulties, and ethical considerations associated with these make finding alternate sources a desirable goal. Periodontal ligament stem cells (PDLSCs) derived from the neural crest were induced into neural‐like cells using a combination of epidermal growth factor, and basic fibroblast growth factor. Morphological changes were evident in our treated group, seen under both light microscopy and scanning electron microscopy. A statistically significant increase in the expression of neuron‐specific β‐tubulin III and the neural stem/progenitor cell marker nestin, along with positive immunohistochemical staining for glial fibrillary acidic protein, demonstrated the success of our treatment in inducing both neuronal and glial phenotypes. Positive staining for synaptophysin demonstrated neural connections and electrophysiological recordings indicated that when subjected to whole‐cell patch clamping, our treated cells displayed inward currents conducted through voltage‐gated sodium (Na+) channels. Taken together, our results indicate the success of our treatment in inducing PDLSCs to neural‐like cells. The ease of sourcing and expansion, their embryologic neural crest origin, and the lack of ethical implications in their use make PDLSCs an attractive source for use in neuroregenerative medicine. J. Cell. Physiol. 229: 479–488, 2014.

Concise Review: Stem Cell Therapies for Neuropathic Pain

Neuropathic pain is a chronic condition that is heterogeneous in nature and has different causes. Different from and more burdensome than nociceptive pain, neuropathic pain more severely affects peoples quality of life. Understanding the various mechanisms of the onset and progression of neuropathic pain is important in the development of an effective treatment. Research is being done to replace current pharmacological treatments with cellular therapies that will have longer lasting effects. Stem cells present an exciting potential therapy for neuropathic pain. In this review, we describe the neuroprotective effects of stem cells along with special emphasis on the current translational research using stem cells to treat neuropathic pain.

Work in progress: Video tutorials that enhance laboratory learning

Laboratories are a means by which students take a hands-on approach and practice concepts learned in class lectures under real or close-to-real world settings. This provides a kinesthetic method of learning which rounds out the auditory methods typical of a lecture course. Unfortunately, many students spend most of the lab time troubleshooting their experiment instead of deepening their understanding of the concepts taught in class. This causes frustration and anxiety amongst students. In our opinion, this is due to a lack of knowledge of equipment used in the lab as well as training on different equipment in previous classes. We have developed a video tutorial series for our Biomedical Measurements class that teaches basic circuit building, equipment set-up, and equipment use - students may watch these videos before the lab and at any moment during the lab. Thus far, post-semester surveys have indicated that all respondents, whether bio-electrical, pre-medical, or bio-mechanical concentration in biomedical engineering, find the video tutorials helpful in the lab. The incorporation of technology in the lab session ensures that the lab time is spent deepening conceptual knowledge instead of troubleshooting circuits.

MicroRNA-132 directs human periodontal ligament-derived neural crest stem cell neural differentiation

Neurogenesis is the basis of stem cell tissue engineering and regenerative medicine for central nervous system (CNS) disorders. We have established differentiation protocols to direct human periodontal ligament‐derived stem cells (PDLSCs) into neuronal lineage, and we recently isolated the neural crest subpopulation from PDLSCs, which are pluripotent in nature. Here, we report the neural differentiation potential of these periodontal ligament‐derived neural crest stem cells (NCSCs) as well as its microRNA (miRNA) regulatory mechanism and function in NCSC neural differentiation. NCSCs, treated with basic fibroblast growth factor and epidermal growth factor‐based differentiation medium for 24 days, expressed neuronal and glial markers (βIII‐tubulin, neurofilament, NeuN, neuron‐specific enolase, GFAP, and S100) and exhibited glutamate‐induced calcium responses. The global miRNA expression profiling identified 60 upregulated and 19 downregulated human miRNAs after neural differentiation, and the gene ontology analysis of the miRNA target genes confirmed the neuronal differentiation‐related biological functions. In addition, overexpression of miR‐132 in NCSCs promoted the expression of neuronal markers and downregulated ZEB2 protein expression. Our results suggested that the pluripotent NCSCs from human periodontal ligament can be directed into neural lineage, which demonstrate its potential in tissue engineering and regenerative medicine for CNS disorders.

Neurogenesis from Stem Cells

This review discusses the present field of neurogenesis using adult stem cells. The authors highlight different methods of differentiating adult stem cells into neural cells: Growth factor and chemical induction, transfection, scaffold and/or 3D culture, and bioreactor and external stimuli. These different methods will be discussed using relevant patents and recent (< 5 year) scientific literature. Additionally, the authors present where they believe the future of neurogenesis from stem cells is headed - the use of neural crest stem cells as the ideal cell source for neurogenesis.

Pluripotent Adult Stem Cells: A Potential Revolution in Regenerative Medicine and Tissue Engineering

Stem cells are undifferentiated cells defined by their abilities to self-renew and differentiate into mature cells. Stem cells found in fully developed tissues are defined as adult stem cells. The function of adult stem cells is the maintenance of adult tissue specificity by homeostatic cell replacement and tissue regeneration (Wagers and Weissman, 2004). Adult stem cells are presumed quiescent within adult tissues, but divide infrequently to generate a stem cell clone and a transiently-amplifying cell. The transiently-amplifying cells will undergo a lim‐ ited number of cell divisions before terminal differentiation into mature functional tissue cells. The existence of adult stem cells has been reported in multiple organs; these include: brain, heart, skin, intestine, testis, muscle and blood, among others. This chapter focuses on four adult stem cell populations: hematopoietic, mesenchymal, periodontal ligament-de‐ rived, and spermatogonial (Table 1).

Novel Pluripotent Adult Stem Cell Source for Neurogenesis

A novel pluripotent stem cell population discovered by our laboratory, periodontal ligament stem cells (PDLSCs) are a viable source for regenerative medicine. We have demonstrated that these cells form all three germ layers in-vivo, and hypothesized that PDLSCs would be an ideal cell source for neurogenesis in-vitro. In our study, we evaluate the potential of Connexin 43+ PDLSCs to differentiate into a neural lineage. Control Connexin 43+ PDLSCs were cultured in complete culture media. Neuro-induced Connexin 43+PDLSCs were grown in a neurogenic cocktail media. Media was changed every three days for a total of 6 days of treatment. Following treatment, cell morphology, gene expression, and immunohistochemistry were evaluated. Gene expression data was analyzed using a two-tailed t-test, with p<;0.05 considered significant. Morphological differences were evident in neuro-induced Connexin 43+ PDLSCs, along with a significant increase in gene expression of neuro filament medium over control samples. Immunohistochemical staining in neuro-induced Connexin 43+ PDLSCs demonstrated neurite-like processes and synaptophysin not found in control samples. Conclusion: Our neuro-induction protocol successfully induces Connexin 43+ PDLSCs to a neural lineage.