Human Umbilical Cord-Derived Schwann-Like Cell Transplantation Combined with Neurotrophin-3 Administration in Dyskinesia of Rats with Spinal Cord Injury

Application of Human Umbilical Cord Mesenchymal Stem Cells in Rat Spinal Cord Injury Model

The treatment of spinal cord injury (SCI) is a hot topic in clinic. In this study, female rats were selected and randomly divided into four groups (normal, sham, SCI, and mesenchymal stem cells [MSCs] groups). Hemostatic forceps were used to clamp the spinal cord for 1 min to establish the SCI animal model in rats. The levels of proinflammatory factors in the blood of each group were compared 4 h after operation. The motor function of hind limb was estimated by Basso, Beattie & Bresnahan Locomotor rating scale (BBB scale) at 3 months after surgery, the spinal cord tissue from the experimental area was obtained and stained histologically and immunohistochemically. Basso, Beattie & Bresnahan Locomotor rating scale results indicated that human umbilical cord (HUC) MSCs transplantation could improve the walking ability in rats with the SCI. Human umbilical cord mesenchymal stem cells substantially upregulated the secretion of anti-inflammatory factors and downregulated the secretion of proinflammatory factors, and promoted the repair of the SCI and inhibited the increase of glial cells induced by the SCI. Human umbilical cord mesenchymal stem cells transplantation can partially recovered the motor ability of rats with the SCI through promoting the regeneration of nerve cell and the expression of neural related genes, and inhibiting inflammatory reaction.

Human Schwann Cell Transplantation for Spinal Cord Injury: Prospects and Challenges in Translational Medicine

The benefits of transplanting cultured Schwann cells (SCs) for the treatment of spinal cord injury (SCI) have been systematically investigated in experimental animals since the early 1990s. Importantly, human SC (hSC) transplantation for SCI has advanced to clinical testing and safety has been established via clinical trials conducted in the USA and abroad. However, multiple barriers must be overcome to enable accessible and effective treatments for SCI patients. This review presents available information on hSC transplantation for SCI with the intention to uncover gaps in our knowledge and discuss areas for future development. To this end, we introduce the historical progression of the work that supports existing and prospective clinical initiatives and explain the reasons for the choice of hSCs while also addressing their limitations as cell therapy products. A search of the relevant literature revealed that rat SCs have served as a preclinical model of reference since the onset of investigations, and that hSC transplants are relatively understudied, possibly due to the sophisticated resources and expertise needed for the traditional processing of hSC cultures from human nerves. In turn, we reason that additional experimentation and a reexamination of the available data are needed to understand the therapeutic value of hSC transplants taking into consideration that the manufacturing of the hSCs themselves may require further development for extended uses in basic research and clinical settings.

Curcumin Improves Human Umbilical Cord-Derived Mesenchymal Stem Cell Survival via ERK1/2 Signaling and Promotes Motor Outcomes After Spinal Cord Injury

Human umbilical cord-derived mesenchymal stem cell (hUC-MSC) transplantation is thought to be a promising strategy for treating spinal cord injury (SCI). However, the low survival rate of transplanted hUC-MSCs limits their clinical application in cell replacement therapy. Curcumin can suppress inflammation after SCI; however, it remains unknown whether curcumin can modulate the survival of transplanted hUC-MSCs. In this study, to investigate whether curcumin could strengthen the therapeutic effects of hUC-MSC transplantation on SCI, we induced hUC-MSC apoptosis with TNF-α, transplanted hUC-MSC into SCI rats, and assessed the antiapoptotic effect and mechanism of curcumin. LDH release analysis and flow cytometry demonstrated that TNF-α led to hUC-MSC apoptosis and that curcumin increased the hUC-MSC survival rate in a dose-dependent manner. In addition, we showed that the phosphorylation levels of ERK1/2, JNK, and P38 were upregulated in apoptotic hUC-MSCs, while curcumin increased the phosphorylation of ERK1/2 but did not activate JNK or P38, and these effects were reversed by the p42/44 antagonist U0126. Furthermore, we found that the motor function scores and number of surviving HNA-positive cells were significantly increased after curcumin and hUC-MSC transplantation therapy 8 weeks post-SCI, while U0126 markedly attenuated these effects. These data confirmed that curcumin suppressed hUC-MSC apoptosis through the ERK1/2 signaling pathway and that combined curcumin and hUC-MSC treatment improved motor function in rats after SCI. The current research provides a strong basis for hUC-MSC replacement therapy in conjunction with curcumin in the treatment and management of SCI in humans.

Umbilical cord-derived mesenchymal stem cells in neurodegenerative disorders: from literature to clinical practice

Mesenchymal stem cells (MSCs) have provided a promising tool for cell therapy. Umbilical cord (UC) is one of the best sources of MSCs since its collection is noninvasive, and effortless, and the cells from this source are more capable and prolific. It has been proven that the differentiation, migration and protective properties of UC-MSCs are superior compared with other kinds of stem cells. Moreover, incurable neurodegenerative diseases, such as Alzheimer's disease, multiple sclerosis, Parkinson's disease and Huntington, encourage scientists to apply UC-MSCs transplantation in order to find a definite treatment. This review will focus on the preclinical and clinical use of mesenchymal stem cells derived from human umbilical cord in the treatment of neurodegenerative disorders.

The Science and Clinical Applications of Placental Tissues in Spine Surgery

STUDY DESIGN

Narrative literature review.

OBJECTIVES

Placental tissue, amniotic/chorionic membrane, and umbilical cord have seen a recent expansion in their clinical application in various fields of surgery. It is important for practicing surgeons to know the underlying science, especially as it relates to spine surgery, to understand the rationale and clinical indication, if any, for their usage.

METHODS

A literature search was performed using PubMed and MEDLINE databases to identify studies reporting the application of placental tissues as it relates to the practicing spine surgeon. Four areas of interest were identified and a comprehensive review was performed of available literature.

RESULTS

Clinical application of placental tissue holds promise with regard to treatment of intervertebral disc pathology, preventing epidural fibrosis, spinal dysraphism closure, and spinal cord injury; however, there is an overall paucity of high-quality evidence. As such, evidence-based guidelines for its clinical application are currently unavailable.

CONCLUSIONS

There is no high-level clinical evidence to support the application of placental tissue for spinal surgery, although it does hold promise for several areas of interest for the practicing spine surgeon. High-quality research is needed to define the clinical effectiveness and indications of placental tissue as it relates to spine surgery.

Analysis of differentially expressed microRNA of TNF-α-stimulated mesenchymal stem cells and exosomes from their culture supernatant

INTRODUCTION

To analyze the microRNA expression of tumor necrosi factor α (TNF-α) stimulated mesenchymal stem cells (MSCs) and exosomes from their culture supernatant.

MATERIAL AND METHODS

TNF-α (20 ng/ml) was used to stimulate MSCs, which were then regarded as TNF-α cells (TC), while unstimulated cells were the normal control cells (NCC). MSCs and their culture supernatant were harvested after 48 h. Subsequently, exosomes were isolated from culture supernatants with ExoQuick-TC and were divided into two groups, TNF-α exosomes (TE) and normal control exosomes (NCE). Then, the microRNAs were measured by high-throughput sequencing and the results were differentially analyzed. Finally, the correlation of the target genes corresponding to differently expressed microRNAs was analyzed by gene ontology (GO) and KEGG pathway analysis.

RESULTS

High-throughput sequencing showed that the cellular compartment (TC vs. NCC) had 280 microRNAs. miR-146a-5p was a uniquely up-regulated microRNA (p < 0.001) and the most significantly down-regulated microRNA among the 279 microRNAs included was miR-150-5p (p < 0.001). There were 180 differentially expressed microRNAs in the exosome compartment (TE vs. NCE), where miR-146-5p (p < 0.001) was one of 176 upregulated microRNAs and miR-203b-5p (p < 0.001) was one of 4 downregulated microRNAs. Coincidentally, bioinformatics analysis showed that IRAK1 was a critical target gene of miR-146-5p related to the Toll-like receptor (TLR) signaling pathway.

CONCLUSIONS

In contrast with the control group, there were significantly differentially expressed microRNAs in both MSCs and exosomes. Interestingly, miR-146a-5p was up-regulated in both comparative groups, and its target gene IRAK1 plays a crucial part in the TLR signaling pathway. These investigations demonstrate a new direction for subsequent inflammation mechanistic studies.

Phase I-II Clinical Trial Assessing Safety and Efficacy of Umbilical Cord Blood Mononuclear Cell Transplant Therapy of Chronic Complete Spinal Cord Injury

Umbilical cord blood-derived mononuclear cell (UCB-MNC) transplants improve recovery in animal spinal cord injury (SCI) models. We transplanted UCB-MNCs into 28 patients with chronic complete SCI in Hong Kong (HK) and Kunming (KM). Stemcyte Inc. donated UCB-MNCs isolated from human leukocyte antigen (HLA ≥4:6)-matched UCB units. In HK, four patients received four 4-μl injections (1.6 million cells) into dorsal entry zones above and below the injury site, and another four received 8-μl injections (3.2 million cells). The eight patients were an average of 13 years after C5-T10 SCI. Magnetic resonance diffusion tensor imaging of five patients showed white matter gaps at the injury site before treatment. Two patients had fiber bundles growing across the injury site by 12 months, and the rest had narrower white matter gaps. Motor, walking index of SCI (WISCI), and spinal cord independence measure (SCIM) scores did not change. In KM, five groups of four patients received four 4-μl (1.6 million cells), 8-μl (3.2 million cells), 16-μl injections (6.4 million cells), 6.4 million cells plus 30 mg/kg methylprednisolone (MP), or 6.4 million cells plus MP and a 6-week course of oral lithium carbonate (750 mg/day). KM patients averaged 7 years after C3-T11 SCI and received 3-6 months of intensive locomotor training. Before surgery, only two patients walked 10 m with assistance and did not need assistance for bladder or bowel management before surgery. The rest could not walk or do their bladder and bowel management without assistance. At about a year (41-87 weeks), WISCI and SCIM scores improved: 15/20 patients walked 10 m ( p = 0.001) and 12/20 did not need assistance for bladder management ( p = 0.001) or bowel management ( p = 0.002). Five patients converted from complete to incomplete (two sensory, three motor; p = 0.038) SCI. We conclude that UCB-MNC transplants and locomotor training improved WISCI and SCIM scores. We propose further clinical trials.

Stem cell therapies in age-related neurodegenerative diseases and stroke

Aging, a complex process associated with various structural, functional and metabolic changes in the brain, is an important risk factor for neurodegenerative diseases and stroke. These diseases share similar neuropathological changes, such as the formation of misfolded proteins, oxidative stress, loss of neurons and synapses, dysfunction of the neurovascular unit (NVU), reduction of self-repair capacity, and motor and/or cognitive deficiencies. In addition to gray matter dysfunction, the plasticity and repair capacity of white matter also decrease with aging and contribute to neurodegenerative diseases. Aging not only renders patients more susceptible to these disorders, but also attenuates their self-repair capabilities. In addition, low drug responsiveness and intolerable side effects are major challenges in the prevention and treatment of senile diseases. Thus, stem cell therapies-characterized by cellular plasticity and the ability to self-renew-may be a promising strategy for aging-related brain disorders. Here, we review the common pathophysiological changes, treatments, and the promises and limitations of stem cell therapies in age-related neurodegenerative diseases and stroke.

The efficacy of Schwann cell transplantation on motor function recovery after spinal cord injuries in animal models: A systematic review and meta-analysis

AIM

This article aimed to assess the efficacy of Schwann cell transplantation on motor function recovery in animal model of spinal cord injuries via meta-analysis.

METHODS

An extended search was carried out in the electronic databases of Medline (via PubMed), EMBASE (via OvidSP), CENTRAL, SCOPUS, Web of Science (BIOSIS), and ProQuest. Finally, 41 eligible studies conducted on 1046 animals including 517 control animals and 529 transplanted animals were included in the meta-analysis. Pooled standardized mean difference (SMD) and odds ratio (OR) with 95% confidence interval (95% CI) were reported.

RESULTS

The findings showed that treatment with Schwann cells leads to a modest motor function recovery after spinal cord injury (SMD=0.85; 95% CI: 0.63-1.07; p<0.001). Transplantation of these cells in acute phase of the injury (immediately after the injury) (OR=4.30; 95% CI: 1.53-12.05; p=0.007), application of mesenchymal/skin-derived precursors (OR=2.34; 95% CI: 1.28-4.29; p=0.008), and cells with human sources are associated with an increase in efficacy of Schwann cells (OR=10.96; 95% CI: 1.49-80.77; p=0.02). Finally, it seems that the efficacy of Schwann cells in mice is significantly lower than rats (OR=0.03; 95% CI: 0.003-0.41; p=0.009).

CONCLUSION

Transplantation of Schwann cells can moderately improve motor function recovery. It seems that inter-species differences might exist regarding the efficacy of this cells. Therefore, this should be taken into account when using Schwann cells in clinical trials regarding spinal cord injuries.

Cell Therapy Augments Functional Recovery Subsequent to Spinal Cord Injury under Experimental Conditions

The spinal cord injury leads to enervation of normal tissue homeostasis ultimately leading to paralysis. Until now there is no proper cure for the treatment of spinal cord injury. Recently, cell therapy in animal spinal cord injury models has shown some progress of recovery. At present, clinical trials are under progress to evaluate the efficacy of cell transplantation for the treatment of spinal cord injury. Different types of cells such as pluripotent stem cells derived neural cells, mesenchymal stromal cells, neural stem cells, glial cells are being tested in various spinal cord injury models. In this review we highlight both the advances and lacuna in the field of spinal cord injury by discussing epidemiology, pathophysiology, molecular mechanism, and various cell therapy strategies employed in preclinical and clinical injury models and finally we discuss the limitations and ethical issues involved in cell therapy approach for treating spinal cord injury.

Schwann cell transplantation and descending propriospinal regeneration after spinal cord injury

After spinal cord injury (SCI), poor ability of damaged axons of the central nervous system (CNS) to regenerate causes very limited functional recovery. Schwann cells (SCs) have been widely explored as promising donors for transplantation to promote axonal regeneration in the CNS including the spinal cord. Compared with other CNS axonal pathways, injured propriospinal tracts display the strongest regenerative response to SC transplantation. Even without providing additional neurotrophic factors, propriospinal axons can grow into the SC environment which is rarely seen in supraspinal tracts. Propriospinal tract has been found to respond to several important neurotrophic factors secreted by SCs. Therefore, the SC is considered to be one of the most promising candidates for cell-based therapies for SCI. Since many reviews have already appeared on topics of SC transplantation in SCI repair, this review will focus particularly on the rationale of SC transplantation in mediating descending propriospinal axonal regeneration as well as optimizing such regeneration by using different combinatorial strategies. This article is part of a Special Issue entitled SI: Spinal cord injury.

Multiple injections of human umbilical cord-derived mesenchymal stromal cells through the tail vein improve microcirculation and the microenvironment in a rat model of radiation myelopathy

Background

At present, no effective clinical treatment is available for the late effects of radiation myelopathy. The aim of the present study was to assess the therapeutic effects of human umbilical cord-derived mesenchymal stromal cells (UC-MSCs) in a rat model of radiation myelopathy.

Methods

An irradiated cervical spinal cord rat model was generated. UC-MSCs were injected through the tail vein at 90, 97, 104 and 111 days post-irradiation. Behavioral tests were performed using the forelimb paralysis scoring system, and histological damage was examined using Nissl staining. The microcirculation in the spinal cord was assessed using von Willebrand factor (vWF) immunohistochemical analysis and laser-Doppler flowmetry. The microenvironment in the spinal cord was determined by measuring the pro-inflammatory cytokines interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in the serum and the anti-inflammatory cytokines brain-derived neurotrophic factor (BDNF) and glial cell-derived neurotrophic factor (GDNF) in the spinal cord.

Results

Multiple injections of UC-MSCs through the tail veil decreased the forelimb paralysis, decreased spinal cord histological damage, increased the number of neurons in the anterior horn of the spinal cord, increased the endothelial cell density and the microvessel density in the white matter and gray matter of the spinal cord, increased the relative magnitude of spinal cord blood flow, down-regulated pro-inflammatory cytokine expression in the serum, and increased anti-inflammatory cytokine expression in the spinal cord.

Conclusion

Multiple injections of UC-MSCs via the tail vein in a rat model of radiation myelopathy significantly improved the microcirculation and microenvironment through therapeutic paracrine effects.

Stem cell-based cell therapy for glomerulonephritis

Glomerulonephritis (GN), characterized by immune-mediated inflammatory changes in the glomerular, is a common cause of end stage renal disease. Therapeutic options for glomerulonephritis applicable to all cases mainly include symptomatic treatment and strategies to delay progression. In the attempt to yield innovative interventions fostering the limited capability of regeneration of renal tissue after injury and the uncontrolled pathological process by current treatments, stem cell-based therapy has emerged as novel therapy for its ability to inhibit inflammation and promote regeneration. Many basic and clinical studies have been performed that support the ability of various stem cell populations to ameliorate glomerular injury and improve renal function. However, there is a long way before putting stem cell-based therapy into clinical practice. In the present article, we aim to review works performed with respect to the use of stem cell of different origins in GN, and to discuss the potential mechanism of therapeutic effect and the challenges for clinical application of stem cells.

Use of umbilical cord and cord blood-derived stem cells for tissue repair and regeneration

INTRODUCTION

Potential use of umbilical cord (UC) is one of the most exciting frontiers in medicine for repairing damaged tissues. UC and cord blood-derived stem cells are the world's largest potential sources of stem cells. UC contains a mixture of stem and progenitor cells at different lineage commitment stages and UC has been verified as a candidate for cell-based therapies and tissue engineering applications due to the capability of these cells for extensive self-renewal and multi-lineage character in differentiation potential.

AREAS COVERED

UC-based repair or regeneration of organs (i.e., heart, nerve, skin, etc.) is a high-priority research worldwide.

EXPERT OPINION

The aim of this review is to summarize the knowledge about UC with main focus on its applications for tissue repair and regeneration.

Human umbilical mesenchymal stem cells attenuate the progression of focal segmental glomerulosclerosis

Previous studies have suggested the potential of mesenchymal stem cells (MSCs) to repair damaged kidney diseases. However, the effect of human umbilical cord MSCs (HuMSCs) on the progression of focal segmental glomerulosclerosis (FSGS) remains poorly understood. Adriamycin-induced nephropathy is a rodent model of chronic kidney disease that has been studied extensively and has enabled a greater understanding of the processes underlying the progression of FSGS. This study aimed to investigate the role of HuMSCs on the progression of kidney disease using a model of adriamycin-induced nephropathy. Human MSCs were labeled with 5-bromo-2'-deoxyuridine to track their localization to the kidneys after infusion. Clinical parameters and histology suggested amelioration of FSGS in MSC-treated animals at 12 weeks, especially in those that received repeated doses. These results were associated with reduced serum interleukin (IL)-6 and tumor necrosis factor-α, transforming growth factor-β levels, connective tissue growth factor messenger RNA expression and upregulated serum IL-10 levels. In short, this experiment found that HuMSCs improved kidney fibrosis and modulated the inflammatory response, suggesting that xenogenic transplantation of HuMSCs is a novel approach for improving the progression of FSGS and may be a promising therapeutic intervention in the future.

Tackling the physiological barriers for successful mesenchymal stem cell transplantation into the central nervous system

Over the past decade a lot of research has been performed towards the therapeutic use of mesenchymal stem cells (MSCs) in neurodegenerative and neuroinflammatory diseases. MSCs have shown to be beneficial in different preclinical studies of central nervous system (CNS) disorders due to their immunomodulatory properties and their capacity to secrete various growth factors. Nevertheless, most of the transplanted cells die within the first hours after transplantation and induce a neuroinflammatory response. In order to increase the efficacy of MSC transplantation, it is thus imperative to completely characterise the mechanisms mediating neuroinflammation and cell death following MSC transplantation into the CNS. Consequently, different components of these cell death- and neuroinflammation-inducing pathways can be targeted in an attempt to improve the therapeutic potential of MSCs for CNS disorders.

Cell transplantation for spinal cord injury: a systematic review

Cell transplantation, as a therapeutic intervention for spinal cord injury (SCI), has been extensively studied by researchers in recent years. A number of different kinds of stem cells, neural progenitors, and glial cells have been tested in basic research, and most have been excluded from clinical studies because of a variety of reasons, including safety and efficacy. The signaling pathways, protein interactions, cellular behavior, and the differentiated fates of experimental cells have been studied in vitro in detail. Furthermore, the survival, proliferation, differentiation, and effects on promoting functional recovery of transplanted cells have also been examined in different animal SCI models. However, despite significant progress, a "bench to bedside" gap still exists. In this paper, we comprehensively cover publications in the field from the last years. The most commonly utilized cell lineages were covered in this paper and specific areas covered include survival of grafted cells, axonal regeneration and remyelination, sensory and motor functional recovery, and electrophysiological improvements. Finally we also review the literature on the in vivo tracking techniques for transplanted cells.

Optimal time-point for neural stem cell transplantation to delay denervated skeletal muscle atrophy

INTRODUCTION

Transplantation of neural stem cells (NSCs) is a promising treatment to delay denervated skeletal muscle atrophy; however, the optimal time-point between peripheral nerve injury and NSC transplantation needs to be determined.

METHODS

Improvement in rat gastrocnemius muscle function was evaluated after NSCs were transplanted into sectioned distal tibial nerves. We also assessed survival and differentiation. ANOVA was used to compare the mean value of the number of neuron-like cells, cross-sectional area amelioration, the amount of activated fibers, and latency and amplitude of the gastrocnemius compound muscle action potential.

RESULTS

The group in which the NSCs were transplanted 1 week after tibial nerve transection had the largest number of neuron-like cells, maximum cross-sectional area amelioration, and maximum amount of activated gastrocnemius fibers compared with all other groups (P < 0.01).

CONCLUSIONS

The optimal time-point for NSC transplantation for delaying denervated skeletal muscle atrophy is 1 week after severing the nerve.