Neural Stem Cell Therapy Research Articles

Isolation and Purification of Self-Renewable Human Neural Stem Cells from iPSCs for Cell Therapy in Experimental Model of Ischemic Stroke.

Neural stem cell therapy has been galvanized by the discovery of pluripotent stem cells. The possibility to generate specialized central nervous system-specific differentiated cells using human somatic cells engineered to become induced pluripotent stem cells (iPSCs) was a game changer. This technology has broad applications in the field of regenerative medicine, in vitro disease modeling, targeted drug discovery, and precision medicine. Currently, iPSCs are one of the most promising cell sources amenable for commercialization and off-the-shelf neural stem cell therapy products. iPSCs exhibit a strong self-renewable ability that supports the development of a virtually unlimited source of neural cells for structural repair in neurological disorders. However, along with this strong proliferative capacity of iPSCs comes the tumorigenic potential of these cells after transplantation. Thus, the isolation and purification of a homogeneous population of human neural stem cells (hNSCs) are of paramount importance to ensure consistency in the composition of the cellular product and to avoid tumor formation in the host brain. This chapter describes the isolation, neuralization, and long-term perpetuation of hNSCs derived from iPSCs through the use of specific growth medium and the preparation of hNSCs for transplantation in an experimental model of stroke. Additionally, we will describe methods to analyze the ischemic stroke and size of grafts using magnetic resonance imaging and OsiriX software and neuroanatomical tracing procedures to study axonal remodeling after ischemic stroke and cell transplantation.

Effect of combination therapy with neural stem cell transplantation and teramethylpyrazine in rats following acute spinal cord injury.

This study was to explore the effects of teramethylpyrazine (TMP) administered in conjunction with neural stem cell transplantation on motor function, pathological lesions and the Janus kinase (JAK)2/signal transducer and activator of transcription 3 signal transduction pathway in rats following acute spinal cord injury (SCI). Female Sprague-Dawley rats were randomly divided into sham, model, neural stem cells (NSCs) and NSCs+TMP groups. Motor function was evaluated using the Basso, Beattie, Bresnahan scale. Spinal cord neuropathies and neuron apoptosis were observed by HE and TUNEL staining. The brain-derived neurotrophic factor (BDNF), Nogo-A, JAK2 and p-JAK2 protein levels were measured by western blot analysis. NSCs+TMP significantly improved rat motor function, attenuated impaired spinal cords, and decreased cellular apoptosis, compared with NSCs therapy alone (P < 0.05). In addition, expression of BDNF protein was significantly higher in NSCs+TMP rats compared with other groups regardless of time postinjury (P < 0.05). The highest expression levels of Nogo-A protein were observed in the model group. The expression of p-JAK2 in the NSCs+TMP group was relatively lower than the model and NSCs groups (P < 0.05). In rats with SCI, NSCs+TMP effectively improved motor function and offered spinal cord protection by increasing BDNF and decreasing Nogo-A levels, as well as inhibiting the JAK2/STAT3 signal transduction pathway, suggesting that TMP could be a useful agent in NSCs transplantation in the treatment of SCI.

Neural stem cell treatment for perinatal brain injury: A systematic review and meta-analysis of preclinical studies.

Perinatal brain injury can lead to significant neurological and cognitive deficits and currently no therapies can regenerate the damaged brain. Neural stem cells (NSCs) have the potential to engraft and regenerate damaged brain tissue. The aim of this systematic review was to evaluate the preclinical literature to determine whether NSC administration is more effective than controls in decreasing perinatal brain injury. Controlled interventional studies of NSC therapy using animal models of perinatal brain injury were identified using MEDLINE and Embase. Primary outcomes were brain infarct size, motor, and cognitive function. Data for meta‐analysis were synthesized and expressed as standardized mean difference (SMD) with 95% confidence intervals (CI), using a random effects model. We also reported secondary outcomes including NSC survival, migration, differentiation, and effect on neuroinflammation. Eighteen studies met inclusion criteria. NSC administration decreased infarct size (SMD 1.09; CI: 0.44, 1.74, P = .001; I 2 = 74%) improved motor function measured via the impaired forelimb preference test (SMD 2.27; CI: 0.85, 3.69, P = .002; I 2 = 86%) and the rotarod test (SMD 1.88; CI: 0.09, 3.67, P = .04; I 2 = 95%). Additionally, NSCs improved cognitive function measured via the Morris water maze test (SMD of 2.41; CI: 1.16, 3.66, P = .0002; I 2 = 81%). Preclinical evidence suggests that NSC therapy is promising for the treatment of perinatal brain injury. We have identified key knowledge gaps, including the lack of large animal studies and uncertainty regarding the necessity of immunosuppression for NSC transplantation in neonates. These knowledge gaps should be addressed before NSC treatment can effectively progress to clinical trial.

Mesenteric Neural Stem Cell for Chronic Spinal Cord Injury: A Literature Review

Spinal cord injury (SCI) is a common and potentially life-threatening condition with no established treatment to treat the primary injury. Mesenteric neural stem cell (NSC) therapy is a promising stem cell therapy to treat primary SCI in the chronic phase. We aimed to review the literature narratively to describe current evidence regarding mesenteric NSC in SCI. Primary SCI refers to tissue damage that occurs at the time of trauma that leads to the death of neuronal cells. In chronic SCI, the ability of neuronal regeneration is compromised by the development of gliotic scar. NSC is a stem cell therapy that targeted SCI in the chronic phase. Enteric NSC is one of the sources of NSC, and autologous gut harvesting in the appendix using endoscopic surgery provides a more straightforward and low-risk procedure. Intramedullary transplantation of stem cell with ultrasound guiding is administration technique which offers long-term regeneration. Mesenteric NSC is a promising stem cell therapy to treat chronic SCI with low risk and easier procedure to isolate cells compared to other NSC sources.

Understanding neural stem cell regulation in vivo and applying the insights to cell therapy for strokes.

The use of neural stem cell (NSC) therapy for the treatment of stroke patients is successfully paving its way into advanced phases of large-scale clinical trials. To understand how to optimize NSC therapeutic approaches, it is fundamental to decipher the crosstalk between NSC and other cells that comprise the NSC microenvironment (niche) and regulate their function, in vivo; namely, the endothelial cells of the microvasculature. In this mini review, we first provide a concise summary of preclinical findings describing the signaling mechanisms between NSC and vascular endothelial cells and vice versa. Second, we describe the progress made in the development of NSC therapy for the treatment of strokes.

Neural stem cells as a promising therapeutic approach in neurological diseases

The central nervous system lacks the ability to undergo neuronal regeneration. Neurological diseases such as neurotrauma and neurovascular diseases impact many people around the world. Neural stem cell-based treatment for neurological diseases limits clinical damage by providing and by regeneration local support for damaged and lost neural cells. Neural stem cells (NSCs) have a vital role in cell therapy as they can give rise to neurons or glial cells and repair neurological injuries. NSCs were able to secrete constitutively neuroprotective factors that have an important role in neurological repair. Moreover, upon transplantation, NSCs were shown capable of migration into lesioned sites and improved functional recovery after neurological diseases due to their important role in neurogenesis, immunomodulation, and brain plasticity. This review focuses on the roles of NSCs-based therapies in neurological diseases and summarise current advancements in NSC transplantation into rodent models of neurological disorders as well as shed the light on the progress of NSCs therapies in clinical trials.

Immunological Responses to Transgene-Modified Neural Stem Cells After Transplantation.

Neural stem cell (NSC) therapy is a promising therapeutic strategy for stroke. Researchers have frequently carried out genetic modification or gene editing of stem cells to improve survival or therapeutic function. However, NSC transplantation carries the risk of immune rejection, and genetic modification or gene-editing might further increase this risk. For instance, recent studies have reported on manipulating the stem cell genome and transplantation via the insertion of an exogenous gene derived from magnetotactic bacteria. However, whether transgene-modified stem cells are capable of inducing immunological reactions has not been explored. Although NSCs rarely express the major histocompatibility complex (MHC), they can still cause some immunological issues. To investigate whether transgene-modified NSCs aggravate immunological responses, we detected the changes in peripheral immune organs and intracerebral astrocytes, glial cells, and MHC-I and MHC-II molecules after the injection of GFP-labeled or mms6-GFP-labeled NSCs in a rat model. Xenogeneic human embryonic kidney (HEK-293T) cells were grafted as a positive control group. Our results indicated that xenogeneic cell transplantation resulted in a strong peripheral splenic response, increased astrocytes, enhanced microglial responses, and upregulation of MHC-I and MHC-II expression on the third day of transplantation. But they decreased obviously except Iba-1 positive cells and MHC-II expression. When injection of both mms6-GFP-labeled NSCs and GFP-labeled NSCs also induced similar responses as HEK-293T cells on the third days, but MHC-I and MHC-II expression decreased 3 weeks after transplantation. In addition, mms6 transgene-modified NSCs did not produce peripheral splenic response responses as well as astrocytes, microglial cells, MHC-I and MHC-II positive cells responses when compared with non-modified NSCs. The present study provides preliminary evidence that transgenic modification does not aggravate immunological responses in NSC transplantation.

Development of next-generation tumor-homing induced neural stem cells to enhance treatment of metastatic cancers.

Engineered tumor-homing neural stem cells (NSCs) have shown promise in treating cancer. Recently, we transdifferentiated skin fibroblasts into human-induced NSCs (hiNSC) as personalized NSC drug carriers. Here, using a SOX2 and spheroidal culture-based reprogramming strategy, we generated a new hiNSC variant, hiNeuroS, that was genetically distinct from fibroblasts and first-generation hiNSCs and had significantly enhanced tumor-homing and antitumor properties. In vitro, hiNeuroSs demonstrated superior migration to human triple-negative breast cancer (TNBC) cells and in vivo rapidly homed to TNBC tumor foci following intracerebroventricular (ICV) infusion. In TNBC parenchymal metastasis models, ICV infusion of hiNeuroSs secreting the proapoptotic agent TRAIL (hiNeuroS-TRAIL) significantly reduced tumor burden and extended median survival. In models of TNBC leptomeningeal carcinomatosis, ICV dosing of hiNeuroS-TRAIL therapy significantly delayed the onset of tumor formation and extended survival when administered as a prophylactic treatment, as well as reduced tumor volume while prolonging survival when delivered as established tumor therapy.

Human-Induced Neural and Mesenchymal Stem Cell Therapy Combined with a Curcumin Nanoconjugate as a Spinal Cord Injury Treatment.

We currently lack effective treatments for the devastating loss of neural function associated with spinal cord injury (SCI). In this study, we evaluated a combination therapy comprising human neural stem cells derived from induced pluripotent stem cells (iPSC-NSC), human mesenchymal stem cells (MSC), and a pH-responsive polyacetal–curcumin nanoconjugate (PA-C) that allows the sustained release of curcumin. In vitro analysis demonstrated that PA-C treatment protected iPSC-NSC from oxidative damage in vitro, while MSC co-culture prevented lipopolysaccharide-induced activation of nuclear factor-κB (NF-κB) in iPSC-NSC. Then, we evaluated the combination of PA-C delivery into the intrathecal space in a rat model of contusive SCI with stem cell transplantation. While we failed to observe significant improvements in locomotor function (BBB scale) in treated animals, histological analysis revealed that PA-C-treated or PA-C and iPSC-NSC + MSC-treated animals displayed significantly smaller scars, while PA-C and iPSC-NSC + MSC treatment induced the preservation of β-III Tubulin-positive axons. iPSC-NSC + MSC transplantation fostered the preservation of motoneurons and myelinated tracts, while PA-C treatment polarized microglia into an anti-inflammatory phenotype. Overall, the combination of stem cell transplantation and PA-C treatment confers higher neuroprotective effects compared to individual treatments.

Poly (L-lactic acid) nanofibrous scaffolds support the proliferation and neural differentiation of mouse neural stem and progenitor cells.

The distribution and growth of cells on nanofibrous scaffolds seem to be an indispensable precondition in cell tissue engineering. The potential use of biomaterial scaffolds in neural stem cell therapy is increasingly attracting attention. In this study, we produced porous nanofibrous scaffolds fabricated from random poly-L-lactic acid (PLLA) to support neurogenic differentiation of neural stem and progenitor cells (NSPCs), isolated from the subventricular zone (SVZ) of the adult mouse brain. The viability and proliferation of the NSPCs on the nanofibrous PLLA scaffold were also tested by nuclear staining with 4, 6-diamidino-2-phenylindole dihydrochloride (DAPI), 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay and scanning electron microscopy (SEM). To investigate the differentiation potential of NSPCs on the scaffolds, the cells were treated with a neurogenic differentiation medium, and immunostaining was done to detect neuronal and glial cells after 14 and 21days of cultivation. Furthermore, the morphology of differentiated cells on the scaffold was examined using SEM. The DAPI staining revealed the proliferation of NSPCs onto the surface of the nanofibrous PLLA scaffold. DAPI-positive cells were counted on days 2 and 5 after cultivation. The mean number of cells in each microscopic field was significantly (p<.05) increased (51±19 on day 2 compared to 77±25 cells on day 5). The results showed that the cell viability on PLLA scaffolds significantly increased compared to control groups. Moreover, cell viability was significantly increased 5days after culturing (262.3±50.2) as compared to 2days culture in Vitro (174.2±28.3, p<.05). Scanning electron micrographs also showed that the NSPCs adhered and differentiated on PLLA scaffolds. We found that the neural cell markers, microtubule-associated protein 2 (MAP2) and glial fibrillary acidic protein (GFAP), were expressed in NSPCs seeded on random PLLA scaffolds after 21days of cultivation. These results suggest that the PLLA nano-scaffolds, due to their biocompatible property, are an appropriate structure for the proliferation, differentiation, and normal growth of NSPCs.

The Rotary Cell Culture System increases NTRK3 expression and promotes neuronal differentiation and migratory ability of neural stem cells cultured on collagen sponge

BackgroundRecently, neural stem cell (NSC) therapy has shown promise for the treatment of many neurological diseases. Enhancing the quality of implanted cells and improving therapeutic efficacy are currently research hotspots. It has been reported that collagen sponge material provided sufficient room for cell growth in all directions and promoted the absorption of nutrients and removal of wastes. And also, the Rotary Cell Culture System (RCCS), which mimics the microgravity environment, can be used to culture cells for tissue engineering.Materials and methodsWe performed the mRNA and miRNA sequencing to elucidate the regulatory mechanism of NSCs cultured on the collagen sponge in the RCCS system. The luciferase assay and Western blot revealed a direct regulatory role between let-7i-5p and neurotrophic receptor tyrosine kinase 3 (NTRK3; also called TrkC). And then, the neural differentiation markers Tuj1 and Map2 were detected by immunofluorescence staining. In the meantime, the migratory ability of NSCs was detected both in vitro and in spinal cord injury animals.ResultsIn this study, we demonstrated that the expression of NTRK3 was elevated in NSCs cultured on collagen sponge in the RCCS system. Furthermore, increased NTRK3 expression was regulated by the downregulation of let-7i-5p. Compared to traditionally cultured NSCs, the NSCs cultured on collagen sponge in the RCCS system exhibited better neuronal differentiation and migratory ability, especially in the presence of NT-3.ConclusionsAs the biological properties and quality of transplanted cells are critical for therapeutic success, the RCCS system combined with the collagen sponge culture system shows promise for applications in clinical practice in the future.

Orexin-A Attenuates Inflammatory Responses in Lipopolysaccharide-Induced Neural Stem Cells by Regulating NF-KB and Phosphorylation of MAPK/P38/Erk Pathways.

BackgroundNeuronal damage is the main cause of neurological diseases. Neural stem cells (NSCs) have the functions of cell repair and replacement of neurons, secretion of neurotrophic factors, and immune regulation of the neural microenvironment.ObjectivePrevious study found that Orexin-A had a protective effect on neurons in the central nervous system, but it is lacking in making great efforts on the function of Orexin-A on NSCs. This study aimed to investigate the anti-inflammatory responses and signaling mechanisms of Orexin-A on lipopolysaccharide (LPS)-induced NSCs.MethodsQuantitative real-time polymerase chain reaction was used to detect the mRNA level. Signaling pathway-related protein expression was detected by Western blot. The proliferation and migration of NSCs were investigated by Cell Counting Kit-8 (CCK-8) detection kit and transwell assay. Besides, the staining of hematoxylin and eosin (HE) was performed to study the morphology of cell.ResultsOrexin-A decreased the pro-inflammatory cytokines of IL-1β, TNF-α, and IL-6 induced by LPS by regulating nuclear factor-k-gene binding (NF-kB) and phosphorylation of P38/Erk-mitogen-activated protein kinases (MAPKs) pathways, but not p-JNK signaling.ConclusionOur findings indicate that Orexin-A can alleviate the inflammatory response of NSC. It can provide beneficial help in neural stem cell therapy applications.

A Nanoformulation-Mediated Multifunctional Stem Cell Therapy with Improved Beta-Amyloid Clearance and Neural Regeneration for Alzheimer's Disease.

Alzheimer's disease (AD) is a common dementia that is currently incurable. The existing treatments can only moderately relieve the symptoms of ADto slow down its progress. How to achieve effective neural regeneration to ameliorate cognitive impairments is a major challenge for current ADtreatment. Here, the therapeutic potential of a nanoformulation-mediated neural stem cell (NSC) therapy capable of simultaneous Aβ clearance and neural regeneration is investigated in a murine model. Genetically engineered NSCs capable of stably and continuously expressing neprilysin (NEP) are developed to enhance Aβdegradation and NSC survival in the brain. A PBAE-PLGA-Ag2 S-RA-siSOX9 (PPAR-siSOX9) nanoformulation with high gene/drug deliverability is synthesized to overcome AD microenvironment-associated adverse effects and to promote neuronal differentiation of the NEP-expressing NSCs. For achieving accurate stereotactic transplantation, Ag2 S quantum-dot-based fluorescence imaging is used to guide NSC transplantation in real time. This strategy shows numerous benefits, including efficient and long-lasting Aβ degradation, improved neural regeneration, and accurate cell transplantation. It is shown that a single administration of this therapy achieves long-term efficacy (6months) with respect to memory reversal and improvement of learning deficits.

Neural Stem Cells Therapy to Treat Neurodegenerative Diseases

Neural stem cells have the ability to proliferation, differentiate and renew, which plays an important role in the growth, maturation and senescence of the human brain. But according to researches, neural stem cells in the brain do not remain active throughout an organism's lifetime. Many neural stem cells become dormant when the brain matures, and may be activated when the body is sick to selectively heal the disease. In recent years, there are many studies on neural stem cells. Joshua[1] and Ting Zhang[2] show that neurodegenerative diseases such as ischemic stroke, Alzheimer's disease and Parkinson's disease can be improved by the transplantation of neural stem cells, however the specific mechanism is not clear. This paper investigates three main questions: Why neural stem cell transplantation is chosen as a treatment? Where does NSCs derive from in clinical transplantation? How does neural stem cell transplantation treat brain diseases? And we also figure out the answers to these three questions. Firstly, transplantation of hypothalamic NSCs can delay the process of aging in the host, and Chemokines and EVs which secreted by neural stem cells can delay aging and defend neurodegenerative diseases. Secondly, the sources of NSCs can be divided into three types. The first is to isolate NSCs from primary tissue and cultivate them in vitro. The second is to produce the required cells by inducing pluripotent stem cells and embryonic stem cells. The third way to get NCS is through transdifferentiation of somatic cells. Thirdly, in brain diseases, transplanted NSCs can migrate from the aggregation site to the site of the disease, reducing damage to the blood-brain barrier, repairing learning and memory abilities that depend on the hippocampus and secreting neurotrophic factors.

EXTH-02. TUMOR-HOMING INDUCED NEURAL STEM CELL THERAPY INHIBITS THE PROGRESSION OF BREAST CANCER BRAIN METASTASIS AND LEPTOMENINGEAL CARCINOMATOSIS

Abstract INTRODUCTION Breast cancer brain metastasis, including leptomeningeal carcinomatosis (LC), remains one of the most lethal CNS diseases. New therapies are urgently needed to treat this highly aggressive disease. Here we used models of both breast cancer brain parenchymal metastasis and leptomeningeal metastasis to investigate the efficacy of engineered tumor-homing neural stem cells (NSCs) therapy. METHODS Personalized NSCs were created using Sox2 overexpression to transdifferentiate human fibroblasts into induced NSCs (iNSCs), followed by genetic engineering to enable iNSCs to secrete cytotoxic TRAIL (iNSC-TRAIL). For the parenchymal metastasis study, iNSC-TRAIL therapy was infused intracerebroventricularly (ICV) into Nude mice bearing established intracranial MDA-MB-231-Br human breast cancer cells expressing fluorescent and bioluminescent reporters. For LC studies, we established the disease model by inoculating Nude mice with MDA-MB-231-Br tumor cells via intracisternal infusion. iNSC-TRAIL therapy was evaluated by infusing therapy ICV either 1 week prior to or 3 days after tumor inoculation to mirror prophylactic or established tumor treatment, respectively. Tumor progression in the brain and spine was monitored by serial bioluminescence imaging (BLI), and survival was analyzed. RESULTS Serial BLI showed ICV-infused iNSC-TRAIL reduced parenchymal tumor volumes by 72% 3 weeks post-ICV infusion, and extended median survival from 37 to 52 days. Testing iNSC-TRAIL therapy against established LC tumors, serial BLI showed ICV iNSC-TRAIL therapy reduced established tumors 196-fold in the brain and 500-fold in the spine within 2 weeks post-infusion, while extending median survival from 25 to 47 days. In the prophylactic LC model, iNSC-TRAIL therapy markedly delayed tumor development with tumors in the brain remaining &amp;gt; 1000-fold smaller than control, and tumors in the spine below the limit of detection through 1 month post-treatment. The therapy also eliminated mortality through 50 days post-therapy. CONCLUSION These data suggest iNSC therapy could be a promising treatment option for breast cancer brain metastasis patients.

Developing Bioinspired Three-Dimensional Models of Brain Cancer to Evaluate Tumor-Homing Neural Stem Cell Therapy.

Engineered neural stem cells (NSCs) have recently emerged as a promising therapy. Acting as a tumor-homing drug-delivery system, NSCs migrate through brain tissue to seek out primary and invasive tumor foci. NSCs can deliver therapeutic agents, such as TNFα-related apoptosis-inducing ligand, directly to the tumor and suppress glioblastoma (GBM) in murine models. While the mainstays for evaluating NSC migration and efficacy have been two-dimensional chemotaxis assays and mouse models, these low-throughput and small-scale systems limit our ability to implant and track these cells for human translation. To circumvent these challenges, we developed a three-dimensional culture system using a matrix of poly-l-lactic acid 6100 microfibers suspended in agar. These bioinspired brain matrices were used to model tumor growth, NSC migration, and efficacy of NSC therapy at small and human scale. Kinetic fluorescent imaging confirmed growth of tumors in both small and human-sized bioinspired brain matrix. Tumors proliferated 50-fold and 3-fold for GBM and human metastatic breast cancer, respectively, over 7 days. We next explored the impact of tumor location on NSC migration. When NSCs were implanted 2 mm lateral from the tumor foci, NSCs colocalized with the GBM within 7 days. In models of multifocal disease, NSCs were found to colocalize with multiple tumors, preferentially migrating to tumor foci closest to the site of NSC implantation. Lastly, therapeutic NSCs were implanted at increasing distances (0, 2, 5, or 10 mm) laterally from GBM foci to investigate the effects of distance on NSC efficacy. Serial imaging showed reduced fluorescence at tumor sites, implicating GBM apoptosis across all distances. NSCs coinjected with tumor induced a near-complete response in <10 days, while NSCs implanted 10 mm laterally from the tumor induced a near-complete response by day 30. Lastly, GBM foci were established in each hemisphere of the model and control or therapeutic NSCs were implanted adjacent to tumor cells in the right hemisphere. Kinetic imaging showed that NSC therapy attenuated progression of GBM foci, while GBM cells treated with control NSC expanded rapidly over 21 days. In conclusion, we developed a new bioinspired model that supports growth of human brain cancer cells and enables rapid tracking of NSC therapy. Impact statement Tumor-homing and tumor-killing-engineered neural stem cell (NSC) therapies have shown immense promise in both preclinical and clinical trials. However, as cell therapies continue to evolve, cost-effective and high-throughput screening assays are needed to assess the proliferation, migration, and efficacy of these cells. In this study, we developed a bioinspired brain matrix for the evaluation of engineered NSCs. Importantly, this matrix is easy to fabricate, scalable, and allows for sterile real-time, noninvasive imaging using our custom bioreactor. We then utilized the bioinspired brain matrix system to answer key questions around the tumor-homing migration and efficacy of engineered NSC therapies that are challenging to address with traditional models.

Bioactive Elastic Scaffolds Loaded with Neural Stem Cells Promote Rapid Spinal Cord Regeneration.

Despite decades of research, spinal cord injury (SCI) still causes irreparable damage to the human body. Key challenges that hinder the regeneration and extension of neurons following SCI must be overcome, including the overexpressed glial scar formation and strong inflammatory responses in lesion tissue. Transplantation of neural stem cells (NSCs) represents a promising therapeutic method due to its beneficial roles like growth factor secretion and anti-inflammation. However, NSCs usually differentiate into astrocytes, which is considered as one potential limitation of current NSC therapy. Herein, we fabricate an elastic poly(sebacoyl diglyceride) (PSeD) scaffold to mimic the mechanical properties of the natural spinal cord. The PSeD scaffold is coated with poly(sebacoyl diglyceride)-isoleucine-lysine-valine-alanine-valine-serine (PSeD-IKVAVS) to create a bioactive interface. The core point of this topic is divided into two parts. First, PSeD is a bioelastomer and its mechanical properties are similar to those of the natural spinal cord. This feature reduces the direct stimulation to the spinal cord tissue by the elastomer and then reduces the immune response or resistance caused by the host spinal cord tissue. Second, the IKVAVS peptide modifies PSeD to create a bioactive interface to support NSC growth and differentiation. In the in vivo study, the number of CD68-positive macrophages decreased in the PSeD-IKVAVS/NSC group compared to that in the SCI group (20% vs 60%). The low inflammation induced by the scaffold was beneficial to NSCs, resulting in increased locomotor recovery, as indicated by the increased Basso-Beattie-Bresnahan score (5, the average score in the PSeD-IKVAVS/NSC group, vs 2, the average score in the SCI group). Based on the above two characteristics, a PSeD-IKVAVS bioelastomer is fabricated, which provides a beneficial and bioactive microenvironment for NSCs after transplantation.

Neuroregeneration and functional recovery after stroke: advancing neural stem cell therapy toward clinical application.

Stroke is a main cause of death and disability worldwide. The ability of the brain to self-repair in the acute and chronic phases after stroke is minimal; however, promising stem cell-based interventions are emerging that may give substantial and possibly complete recovery of brain function after stroke. Many animal models and clinical trials have demonstrated that neural stem cells (NSCs) in the central nervous system can orchestrate neurological repair through nerve regeneration, neuron polarization, axon pruning, neurite outgrowth, repair of myelin, and remodeling of the microenvironment and brain networks. Compared with other types of stem cells, NSCs have unique advantages in cell replacement, paracrine action, inflammatory regulation and neuroprotection. Our review summarizes NSC origins, characteristics, therapeutic mechanisms and repair processes, then highlights current research findings and clinical evidence for NSC therapy. These results may be helpful to inform the direction of future stroke research and to guide clinical decision-making.

56. TUMOR-HOMING STEM CELL THERAPY INHIBITS THE PROGRESSION OF BREAST CANCER LEPTOMENINGEAL CARCINOMATOSIS

INTRODUCTIONLeptomeningeal carcinomatosis remains one of the most lethal forms of central nervous system metastasis, with a median survival of only 4 months. Effective new therapies are urgently needed to treat this highly aggressive cancer. In this study, we used models of both prophylactic and established leptomeningeal disease to investigate the efficacy of engineered tumor-homing neural stem cells (NSCs) therapy for breast cancer leptomeningeal carcinomatosis.METHODSPersonalized NSC carriers were created using Sox2 overexpression to transdifferentiate human fibroblasts into induced NSCs (iNSCs) that home to cancer cells and carry therapeutic agents to induce tumor kill. Leptomeningeal models were created by engineering MDA-MB231-Br human breast cancer cells with fluorescent and bioluminescent reporters, then using intracisternal injection to inoculate Nude mice with the tumor cells. iNSC therapy was evaluated by infusing iNSCs releasing the pro-apoptotic agent TRAIL into the lateral ventricle of mice either 1 week prior to or 3 days after tumor inoculation for prophylactic or established tumor treatment respectively. Tumor progression in the brain and spinal cord was monitored by serial bioluminescence imaging (BLI).RESULTSSerial BLI showed that intracerebroventricular (ICV) iNSC-TRAIL therapy reduced the volume of metastatic tumor burden 99.49% in the brain and 99.80% in the spine within 2 weeks post-infusion and extended survival from 24 to 42 days. Additionally, prophylactic iNSC-TRAIL therapy delivered ICV markedly delayed tumor development, with tumors in the brain remaining >1000-fold smaller than control through 1-month post-treatment, below the limit of detection in the spinal cord through 1 month, and eliminating mortality through 50 days post-therapy.CONCLUSIONThese data suggest that iNSC therapy could be a promising treatment option for breast cancer patients with leptomeningeal carcinomatosis.

Oriented Neural Spheroid Formation and Differentiation of Neural Stem Cells Guided by Anisotropic Inverse Opals.

Isotropic inverse opal structures have been extensively studied for the ability to manipulate cell behaviors such as attachment, migration, and spheroid formation. However, their use in regulate the behaviors of neural stem cells has not been fully explored, besides, the isotropic inverse opal structures usually lack the ability to induce the oriented cell growth which is fundamental in neural regeneration based on neural stem cell therapy. In this paper, the anisotropic inverse opal substrates were obtained by mechanically stretching the poly (vinylidene fluoride) (PVDF) inverse opal films. The anisotropic inverse opal substrates possessed good biocompatibility, optical properties and anisotropy, provided well guidance for the formation of neural spheroids, the alignment of neural stem cells, the differentiation of neural stem cells, the oriented growth of derived neurons and the dendritic complexity of the newborn neurons. Thus, we conclude that the anisotropic inverse opal substrates possess great potential in neural regeneration applications.