Clinical effects of intrathecal administration of expanded Wharton jelly mesenchymal stromal cells in patients with chronic complete spinal cord injury: a randomized controlled study

Background aimsSpinal cord injury (SCI) represents a devastating condition leading to severe disability related to motor, sensory and autonomic dysfunction. Stem cell transplantation is considered a potential emerging therapy to stimulate neuroplastic and neuroregenerative processes after SCI. In this clinical trial, the authors investigated the safety and clinical recovery effects of intrathecal infusion of expanded Wharton jelly mesenchymal stromal cells (WJ-MSCs) in chronic complete SCI patients.MethodsThe authors designed a randomized, double-blind, crossover, placebo-controlled, phase 1/2a clinical trial (NCT03003364). Participants were 10 patients (7 males, 3 females, age range, 25–47 years) with chronic complete SCI (American Spinal Injury Association A) at dorsal level (T3-11). Patients were randomly assigned to receive a single dose of intrathecal ex vivo-expanded WJ-MSCs (10 × 10⁶ cells) from human umbilical cord or placebo and were then switched to the other arm at 6 months. Clinical evaluation (American Spinal Injury Association impairment scale motor and sensory score, spasticity, neuropathic pain, electrical perception and pain thresholds), lower limb motor evoked potentials (MEPs) and sensory evoked potentials (SEPs), Spinal Cord Independence Measure and World Health Organization Quality of Life Brief Version were assessed at baseline, 1 month, 3 months and 6 months after each intervention. Urodynamic studies and urinary-specific quality of life (Qualiveen questionnaire) as well as anorectal manometry, functional assessment of bowel dysfunction (Rome III diagnostic questionnaire) and severity of fecal incontinence (Wexner score) were conducted at baseline and at 6 months after each intervention.ResultsIntrathecal transplantation of WJ-MSCs was considered safe, with no significant side effects. Following MSC infusion, the authors found significant improvement in pinprick sensation in the dermatomes below the level of injury compared with placebo. Other clinically relevant effects, such as an increase in bladder maximum capacity and compliance and a decrease in bladder neurogenic hyperactivity and external sphincter dyssynergy, were observed only at the individual level. No changes in motor function, spasticity, MEPs, SEPs, bowel function, quality of life or independence measures were observed.ConclusionsIntrathecal transplantation of human umbilical cord-derived WJ-MSCs is a safe intervention. A single intrathecal infusion of WJ-MSCs in patients with chronic complete SCI induced sensory improvement in the segments adjacent to the injury site.     

Clinical analysis of the treatment of spinocerebellar ataxia and multiple system atrophy-cerebellar type with umbilical cord mesenchymal stromal cells

Background aimsThe aims of this study were to observe the safety and effectiveness of umbilical cord mesenchymal stromal cells (UC-MSC) in the treatment of spinocerebellar ataxia (SCA) and multiple system atrophy-cerebellar type (MSA-C).MethodsFrom October 2009 to September 2010, 14 cases of SCA and 10 cases of MSA-C were given UC-MSC by weekly intrathecal injection, at a dose of 1 × 10⁶/kg four times as one course. All the patients received one course of treatment, except three patients who received two courses. The movement ability and quality of daily life were evaluated with the International Cooperative Ataxia Rating Scale (ICARS) and Activity of Daily Living Scale (ADL) and the scores compared with those before cell therapy. A follow-up of 6–15 months was carried out for all of the patients.ResultsThe results showed that the ICARS and ADL scores were significantly decreased 1 month after treatment (P < 0.01). The symptoms, including unstable walking and standing, slow movement, fine motor disorders of the upper limbs, writing difficulties and dysarthria, were greatly improved except for one patient, who had no response. The observed side-effects included dizziness (four patients), back pain (two cases) and headache (one case), which disappeared within 1–3 days. During the follow-up, 10 cases remained stable for half a year or longer, while 14 cases had regressed to the status prior to the treatment within 1–14 months (an average of 3 months).ConclusionsIntrathecal injection of UC-MSC is safe and can delay the progression of neurologic deficits for SCA and MSA-C patients.     

Efficacy of mesenchymal stromal cells intraspinal transplantation for patients with different degrees of spinal cord injury: A systematic review and meta-analysis

Background aimsSeveral studies have reported that mesenchymal stromal cells (MSCs) may improve neurological functions in patients with spinal cord injury (SCI). In this study, we conducted a systematic review and meta-analysis to summarize the effects of MSC treatment on different degrees of severity of SCI.MethodsSystematic searching of studies reporting outcomes of MSCs on specific injury severities of patients with SCI was performed in The National Library of Medicine (MEDLINE), Embase and Cochrane for published articles up to the 6 July 2022. Two investigators independently reviewed the included studies and extracted the relevant data. The standardized mean differences of American Spinal Injury Association (ASIA) motor score, ASIA light touch scores, ASIA pinprick scores and the Barthel index between baseline and follow-ups were pooled.ResultsA total of eight studies were included. A large majority focused on patients with ASIA grade A classification. The pooled mean differences of ASIA motor scores, ASIA light touch scores, ASIA pinprick scores and the Barthel index were –2.78 (95% confidence interval [CI] –5.12 to –0.43, P = 0.02), –18.26 (95% CI –26.09 to –10.43, P < 0.01), –17.08 (95% CI –24.10 to –10.07, P < 0.01) and –4.37 (95% CI –10.96 to 2.22, P = 0.19), respectively.ConclusionsMSC transplantation was a significantly effective therapy for patients with SCI with ASIA grade A. In the future, further studies are warranted to confirm the potential beneficial effects of MSC therapy.     

Repeated subarachnoid administrations of allogeneic human umbilical cord mesenchymal stem cells for spinal cord injury: a phase 1/2 pilot study

Background aimsStem cell transplantation is a potential treatment for intractable spinal cord injury (SCI), and allogeneic human umbilical cord mesenchymal stem cells (hUC-MSCs) are a promising candidate because of the advantages of immune privilege, paracrine effect, immunomodulatory function, convenient collection procedure and little ethical concern, and there is an urgent need to develop a safe and effective protocol regarding their clinical application.MethodsA prospective, single-center, single-arm study in which subjects received four subarachnoid transplantations of hUC-MSCs (1 × 10⁶ cells/kg) monthly and were seen in follow-up four times (1, 3, 6 and 12 months after final administration) was conducted. At each scheduled time point, safety and efficacy indicators were collected and analyzed accordingly. Adverse events (AEs) were used as a safety indicator. American Spinal Injury Association (ASIA) and SCI Functional Rating Scale of the International Association of Neurorestoratology (IANR-SCIFRS) total scores at the fourth follow-up were determined as primary efficacy outcomes, whereas these two indicators at the remaining time points as well as scores of pinprick, light touch, motor and sphincter, muscle spasticity and spasm, autonomic system, bladder and bowel functions, residual urine volume (RUV) and magnetic resonance imaging (MRI) were secondary efficacy outcomes. Subgroup analysis of primary efficacy indicators was also performed.ResultsSafety and efficacy assessments were performed on 102 and 41 subjects, respectively. Mild AEs involving fever (14.1%), headache (4.2%), transient increase in muscle tension (1.6%) and dizziness (1.3%) were observed following hUC-MSC transplantation and resolved thoroughly after conservative treatments. There was no serious AE. ASIA and IANR-SCIFRS total scores revealed statistical increases when compared with the baselines at different time points during the study, mainly reflected in the improvement of pinprick, light touch, motor and sphincter scores. Moreover, subjects showed a continuous and remarkable decrease in muscle spasticity. Regarding muscle spasm, autonomic system, bladder and bowel functions, RUV and MRI, data/imaging at final follow-up showed significant improvements compared with those at first collection. Subgroup analysis found that hUC-MSC transplantation improved neurological functions regardless of injury characteristics, including level, severity and chronicity.ConclusionsThe authors’ present protocol demonstrates that intrathecal administration of' allogeneic hUC-MSCs at a dose of 10⁶ cells/kg once a month for 4 months is safe and effective and leads to significant improvement in neurological dysfunction and recovery of quality of life.     

Safety and possible outcome assessment of autologous Schwann cell and bone marrow mesenchymal stromal cell co-transplantation for treatment of patients with chronic spinal cord injury

Background aimsCell replacement therapy has become a promising issue that has raised much hope in the regeneration of central nervous system injury. Evidence indicates that successful functional recovery in patients with spinal cord injury will not simply emphasize a single therapeutic strategy. Therefore, many recent studies have used combination strategies for spinal cord regeneration.MethodsWe assessed the safety and feasibility of a bone marrow mesenchymal stromal cell and Schwann cell combination for the treatment of patients with chronic spinal cord injury. Eight subjects who received a complete traumatic spinal cord injury (American Spinal Injury Association [ASIA] classification A) enrolled in this study. The patients received this autologous combination of cells directly into the injury site. The mean duration of follow-up was approximately 24 months.ResultsNo magnetic resonance imaging evidence of neoplastic tissue overgrowth, syringomyelia or psuedomeningocele in any of the patients was seen during the study. There was no deterioration in sensory or motor function in any of the patients during the course of the study. Three patients had negligible improvement in ASIA sensory scale. No motor score improvement and no change in ASIA classification was seen. The patients had widely subjective changes in the course of the study such as urination and defecation sensation and more stability and trunk equilibrium in the sitting position.ConclusionsThere were no adverse findings at least 2 years after autologous transplantation of Schwann cell and mesenchymal stromal cell combination into the injured spinal cord. It appears that the use of this combination of cells is safe for clinical application to spinal cord regeneration.     

Effect of naftopidil,an alpha1D/A-adrenoceptor antagonist,on the urinary bladder in rats with spinal cord injury

AimsAlpha_1D-adrenoceptors (α_1D-ARs) located in the spinal cord are involved in the control of lower urinary tract function. In order to clarify the effect of α_1D-ARs on storage function in the spinal cord, we examined the effect of oral administration and intrathecal injection of the α_1D/A-AR antagonist, naftopidil, on bladder activity, as well as the effect of naftopidil on bladder wall histology, in female rats with spinal cord injury (SCI).Main methodsAdult female Sprague–Dawley rats with Th9–10 spinal cord transection were used. In SCI rats with or without 5 mg/day of naftopidil for 4 weeks, bladder activity was examined via continuous cystometry. In other SCI rats, bladder activity was examined before and after intrathecal injection of naftopidil. In addition, bladder wall histology was compared between SCI rats with or without oral administration of naftopidil for 4 weeks.Key findingsOral administration of naftopidil decreased the number of non-voiding contractions (NVCs). Intrathecal injection of naftopidil prolonged the interval between voiding contractions, decreased the maximum voiding contraction pressure and the number of NVCs, and increased bladder capacity without affecting the residual urine volume. Oral administration of naftopidil also decreased bladder wall fibrosis.SignificanceThe α_1D/A-AR antagonist naftopidil might act on the bladder and spinal cord to improve detrusor hyperreflexia in the storage state in SCI female rats. Naftopidil also suppressed bladder wall fibrosis, suggesting that it may be effective for the treatment of neurogenic lower urinary tract dysfunction after SCI.     

Intrathecal administration of autologous mesenchymal stromal cells for spinal cord injury: Safety and efficacy of the 100/3 guideline

Background aims

Cell therapy with autologous mesenchymal stromal cells (MSCs) in patients with spinal cord injury (SCI) is beginning, and the search for its better clinical application is an urgent need.

人脐带间充质干细胞移植治疗脊髓损伤的研究进展

脊髓损伤（SCI）由于复杂病理生理和神经修复再生困难,至今仍旧是难以攻克的医学难题,而干细胞因其神经再生和神经保护特性被认为是治疗SCI最有希望的方法。其中人脐带间充质干细胞（HUC-MSCs）近年培养分化方法不断改进、神经修复机制初步阐明,联合移植等综合治疗方案也不断实践,使HUC-MSCs移植治疗效果提高。另外关于HUC-MSCs治疗SCI的临床试验逐渐开展,术后患者神经功能恢复改善且无严重并发症出现,表明干细胞移植应用于人体是安全有效的。本文就HUC-MSCs治疗SCI的研究状况及进展进行综述。     

Co-transplantation of olfactory ensheathing glia and mesenchymal stromal cells does not have synergistic effects after spinal cord injury in the rat

Background aimsOlfactory ensheathing glia (OEG) and mesenchymal stromal cells (MSC) are suitable candidates for transplantation therapy of spinal cord injury (SCI). Both facilitate functional improvement after SCI by producing trophic factors and cytokines. In this study, the co-transplantation of both types of cells was studied to clarify their additive and/ or synergistic effects on SCI.MethodsA balloon-induced compression lesion was used to produce SCI in rats. OEG, MSC or both OEG and MSC (3 × 10⁵ cells of each cell type) were implanted by intraspinal injection 1 week after SCI. The effect of transplantation was assessed using behavioral, electrophysiologic and histologic methods.ResultsHindlimb function was examined with Basso, Beattie and Bresnahan (BBB) and Plantar tests. Improvement was found in all three groups of transplanted rats with different time–courses, but there was no significant difference among the groups at the end of the experiment. Motor-evoked potentials after SCI decreased in amplitude from 7 mV to 10 µV. Linear regression analysis showed a modest recovery in amplitude following transplantation, but no change in the control rats. Histologic findings showed that the white and gray matter were significantly spared by transplantation after SCI.ConclusionsFunctional improvement was achieved with transplantation of OEG and/or MSC, but the co-transplantation of OEG and MSC did not show synergistic effects. The poor migration of OEG and MSC might prevent their concerted action. Pre-treatment with a Rho antagonist and a combination of intraspinal and intravenous injection of the cells might be beneficial for SCI therapy.     

Co-transplantation of mesenchymal stromal cells and cord blood cells in treatment of diabetes

Background aimsStem cells provide a promising source for treatment of type 1 diabetes, but the treatment strategy and mechanism remain unclear. The aims of this study were to investigate whether co-transplantation of umbilical cord-derived mesenchymal stromal cells (UC-MSCs) and cord blood mononuclear cells (CB-MNCs) could reverse hyperglycemia in type 1 diabetic mice and to determine the appropriate ratio for co-transplantation. The treatment mechanism was also studied.MethodsA simple and efficient isolation method was developed to generate qualified UC-MSCs. UC-MSCs and CB-MNCs were then transplanted into type 1 diabetic mice at different ratios (UC-MSCs to CB-MNCs = 1:1, 1:4, 1:10) to observe the change in blood glucose concentration. Histology, immunohistochemistry, and human Alu polymerase chain reaction assay were performed to evaluate for the presence of donor-derived cells and the repair of endogenous islets. We also induced UC-MSCs into islet-like cells under specific culture conditions to determine their differentiate potential in vitro.ResultsCo-transplantation of UC-MSCs and CB-MNCs at a ratio of 1:4 effectively reversed hyperglycemia in diabetic mice. The detection of human Alu sequence indicated that the engraftment of donor-derived cells had homed into the recipient's pancreas and kidney. Although neither human insulin nor human nuclei antigen was detected in the regenerated pancreas, UC-MSCs could differentiate into insulin-secreted cells in vitro.ConclusionsCo-transplantation of UC-MSCs and CB-MNCs at a ratio of 1:4 could efficiently reverse hyperglycemia and repair pancreatic tissue.     

HSP70 alleviates spinal cord injury by activating the NF-kB pathway

Objectives:Spinal cord injury (SCI) is an acute traumatic lesion of neurons in the spinal cord which has a high prevalence in the world, and has no effective surgical treatment. HSP70 is a molecular chaperone protein, serves a protective role in several different models of nervous system injury. The aim of the present study was to investigate the anti-inflammatory role of HSP70 in spinal cord injury and explore its mechanism.Methods:In vivo and in vitro models were constructed to mimic SCI. The Basso Mouse Scale (BMS) was applied to assess SCI degrees of the mouse model. Immunofluorescence (IF) was used for visualizing HSP70 and Iba1 in the spinal cord. Western blot assay was employed to quantify HSP70 and p65, and ELISA was for IL-1β and TNF-α.Results:The results showed that HSP70 expression decreased after SCI. HSP70 and Iba1 showed a decrease of co-localization in SCI mice. Further studies revealed that p65 was upregulated during the process of SCI. Overexpression of HSP70 inhibited the expression of p65 both in vitro and in vivo, and promoted the recovery of SCI mice.Conclusions:HSP70 was involved in the pathological process of spinal cord injury, HSP70 alleviated the spinal cord injury via inhibiting NF-κB signaling pathway.     

Intrathecal cell therapy with autologous stromal cells increases cerebral glucose metabolism and can offer a new approach to the treatment of Alzheimer's type dementia

Background aimsAfter recent observations that intrathecal administration of autologous bone marrow mesenchymal stromal cells (MSCs) increases cerebral metabolism in patients with severe traumatic brain injury (TBI), we examined this type of cell therapy in Alzheimer's type dementia.MethodsThree patients with clinical diagnosis of Alzheimer's disease received every 3 months 100million autologous MSCs by intrathecal route, until a total dose of 300million.ResultsDuring cell therapy the patients showed arrest in neurological deterioration and two of them manifested clear improvement of previous symptoms. A global increase in cerebral glucose metabolism, measured using 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET), was observed after every administration of cell therapy.ConclusionsOur present findings suggest that intrathecal administrations of autologous MSCs can be a new strategy for the treatment of Alzheimer's dementia.     

Review of operative considerations in spinal cord stem cell therapy

Spinal cord injury (SCI) can permanently impair motor and sensory function and has a devastating cost to patients and the United States healthcare system. Stem cell transplantation for treatment of SCI is a new technique aimed at creating biological functional recovery. Operative techniques in stem cell transplantation for SCI are varied. We review various clinical treatment paradigms, surgical techniques and technical considerations important in SCI treatment. The NCBI PubMed database was queried for “SCI” and “stem cell” with a filter placed for “clinical trials”. Thirty-nine articles resulted from the search and 29 were included and evaluated by study authors. A total of 10 articles were excluded (9 not SCI focused or transplantation focused, 1 canine model). Key considerations for stem cell transplantation include method of delivery (intravenous, intrathecal, intramedullary, or excision and engraftment), time course of treatment, number of treatments and time from injury until treatment. There are no phase III clinical trials yet, but decreased time from injury to treatment and a greater number of stem cell injections both seem to increase the chance of functional recovery.     

Improvement of contusive spinal cord injury in rats by co-transplantation of gamma-aminobutyric acid-ergic cells and bone marrow stromal cells

Background aimsCell therapy is considered a promising option for treatment of spinal cord injury (SCI). The purpose of this study is to use combined therapy of bone marrow stromal cells (BMSCs) and BMSC-derived gamma-aminobutyric acid (GABA)ergic inhibitory neurotransmitter cells (BDGCs) for the contusion model of SCI in rats.MethodsBDGCs were prepared from BMSCs by pre-inducing them with β-mercaptoethanol followed by retinoic acid and then inducing them by creatine. They were immunostained with BMSC, proneuronal, neural and GABA markers. The BDGCs were intraspinally transplanted into the contused rats, whereas the BMSCs were delivered intravenously. The animals were sacrificed after 12 weeks.ResultsThe Basso, Beattie and Bresnahan test showed improvement in the animals with the combined therapy compared with the untreated animals, the animals treated with GABAergic cells only and the animals that received BMSCs. The immunohistochemistry analysis of the tissue sections prepared from the animals receiving the combined therapy showed that the transplanted cells were engrafted and integrated into the injured spinal cord; in addition, a significant reduction was seen in the cavitation.ConclusionsThe study shows that the combination of GABAergic cells with BMSCs can improve SCI.     

Current evidence on mesenchymal stem cell therapy for traumatic spinal cord injury: systematic review and meta-analysis

Background aimsThe authors aim to analyze the evidence in the literature regarding the efficacy and safety of mesenchymal stem cell (MSC) therapy in human subjects with traumatic spinal cord injury (SCI) and identify its potential role in the management of SCI.MethodsThe authors conducted independent and duplicate searches of electronic databases, including PubMed, Embase and the Cochrane Library, until May 2020 for studies analyzing the efficacy and safety of stem cell therapy for SCI. American Spine Injury Association (ASIA) impairment scale (AIS) grade improvement, ASIA sensorimotor score, activities of daily living score, residual urine volume, bladder function improvement, somatosensory evoked potential (SSEP) improvement and adverse reactions were the outcomes analyzed. Analysis was performed in R platform using OpenMeta[Analyst] software.ResultsNineteen studies involving 670 patients were included for analysis. On analysis, the intervention group showed statistically significant improvement in AIS grade (P < 0.001), ASIA sensory score (P < 0.017), light touch (P < 0.001), pinprick (P = 0.046), bladder function (P = 0.012), residual urine volume (P = 0.023) and SSEP (P = 0.002). However, no significant difference was noted in motor score (P = 0.193) or activities of daily living score (P = 0.161). Although the intervention group had a significant increase in complications (P < 0.001), no serious or permanent adverse events were reported. On subgroup analysis, low concentration of MSCs (<5 × 10⁷ cells) and initial AIS grade A presentation showed significantly better outcomes than their counterparts.ConclusionsThe authors’ analysis establishes the efficacy and safety of MSC transplantation in terms of improvement in AIS grade, ASIA sensory score, bladder function and electrophysiological parameters like SSEP compared with controls, without major adverse events. However, further research is needed to standardize dose, timing, route and source of MSCs used for transplantation.     

Expression and role of Toll-like receptors on human umbilical cord mesenchymal stromal cells

Background aimsToll-like receptors (TLRs) play an important role in innate and adaptive immunity by recognizing pathogen-associated molecular patterns (PAMPs).MethodsIn the present study, we investigated the expression and role of TLRs on human umbilical cord mesenchymal stromal cells (UC-MSCs). The proliferation, differentiation and immunoregulatory activity of UC-MSCs primed with or without TLR ligands were determined.ResultsAt the RNA level, the expression of TLR2, 4, 6 and 9 was relatively higher than that of other TLRs. However, TLR3 and TLR4 expression were relatively higher at the protein level. UC-MSCs expressed functional TLRs by nuclear factor-κB activation and cytokine expression assay. Poly-inosinic acid:cytidylic acid [Poly(I:C)] stimulation inhibited the proliferation of UC-MSCs, but the ligand of other TLRs had no significant effect. Poly(I:C) stimulation enhanced the adipogenic differentiation capability of UC-MSCs, but lipopolysaccharide inhibited the adipogenic differentiation. Poly(I:C) and CpG-oligonucleotide promoted the immunosuppressive potentiality of UC-MSCs, accompanied with the phosphorylation of interferon regulatory factor 3 (IRF3) and increased expression of indoleamine 2,3-dioxygenase and interferon β, whereas activation of other TLR ligands (synthetic analog fibroblast-stimulating lipopeptide-1 and lipopolysaccharide) failed to affect the immunoregulatory activity of UC-MSCs.ConclusionsTaken together, our data demonstrated that TLR activation influenced the function of UC-MSCs, which might have important implications in future efforts to explore the clinical potentials of UC-MSCs.     

Infusion of haploidentical hematopoietic stem cells combined with mesenchymal stem cells for treatment of severe aplastic anemia in adult patients yields curative effects

Background aimsDespite the great advances in immunosuppressive therapy for severe aplastic anemia (SAA), most patients are not completely cured. Haploidentical hematopoietic stem cell transplantation (haplo-HSCT) has been recommended as an alternative treatment in adult SAA patients. However, haplo-HSCT presents a higher incidence of graft failure and graft-versus-host disease (GVHD). The authors designed a combination of haplo-HSCT and umbilical cord-derived mesenchymal stem cells (UC-MSCs) for treatment of SAA in adult patients and evaluated its effects.MethodsAdult patients (≥18 years) with SAA (N = 25) were given HLA-haploidentical hematopoietic stem cells (HSCs) combined with UC-MSCs after a conditioning regimen consisting of busulfan, cyclophosphamide, fludarabine and anti-thymocyte globulin and intensive GVHD prophylaxis, including cyclosporine, basiliximab, mycophenolate mofetil and short-term methotrexate. Additionally, the effects of the protocol in adult SSA patients were compared with those observed in juvenile SAA patients (N = 75).ResultsAll patients achieved myeloid engraftment after haplo-HSCT at a median of 16.12 days (range, 11–26). The median time of platelet engraftment was 28.30 days (range, 13–143). The cumulative incidence of grade II acute GVHD (aGVHD) at day +100 was 32.00 ± 0.91%. No one had grade III–IV aGVHD at day +100. The cumulative incidence of total chronic GVHD was 28.00 ± 0.85%. The overall survival was 71.78 ± 9.05% at a median follow-up of 42.08 months (range, 2.67–104). Promisingly, the protocol yielded a similar curative effect in both young and adult SAA patients.ConclusionsThe authors’ data suggest that co-transplantation of HLA-haploidentical HSCs and UC-MSCs may provide an effective and safe treatment for adult SAA.     

Therapeutic potential of human umbilical cord mesenchymal stem cells in the treatment of rheumatoid arthritis

Introduction

Rheumatoid arthritis (RA) is a T-cell-mediated systemic autoimmune disease, characterized by synovium inflammation and articular destruction. Bone marrow mesenchymal stem cells (MSCs) could be effective in the treatment of several autoimmune diseases. However, there has been thus far no report on umbilical cord (UC)-MSCs in the treatment of RA. Here, potential immunosuppressive effects of human UC-MSCs in RA were evaluated.

Methods

The effects of UC-MSCs on the responses of fibroblast-like synoviocytes (FLSs) and T cells in RA patients were explored. The possible molecular mechanism mediating this immunosuppressive effect of UC-MSCs was explored by addition of inhibitors to indoleamine 2,3-dioxygenase (IDO), Nitric oxide (NO), prostaglandin E2 (PGE2), transforming growth factor β1 (TGF-β1) and interleukin 10 (IL-10). The therapeutic effects of systemic infusion of human UC-MSCs on collagen-induced arthritis (CIA) in a mouse model were explored.

Results

In vitro, UC-MSCs were capable of inhibiting proliferation of FLSs from RA patients, via IL-10, IDO and TGF-β1. Furthermore, the invasive behavior and IL-6 secretion of FLSs were also significantly suppressed. On the other hand, UC-MSCs induced hyporesponsiveness of T cells mediated by PGE2, TGF-β1 and NO and UC-MSCs could promote the expansion of CD4⁺ Foxp3⁺ regulatory T cells from RA patients. More importantly, systemic infusion of human UC-MSCs reduced the severity of CIA in a mouse model. Consistently, there were reduced levels of proinflammatory cytokines and chemokines (TNF-α, IL-6 and monocyte chemoattractant protein-1) and increased levels of the anti-inflammatory/regulatory cytokine (IL-10) in sera of UC-MSCs treated mice. Moreover, such treatment shifted Th1/Th2 type responses and induced Tregs in CIA.

Conclusions

In conclusion, human UC-MSCs suppressed the various inflammatory effects of FLSs and T cells of RA in vitro, and attenuated the development of CIA in vivo, strongly suggesting that UC-MSCs might be a therapeutic strategy in RA. In addition, the immunosuppressive activitiy of UC-MSCs could be prolonged by the participation of Tregs.