Umbilical Cord Mesenchymal Stem Cells Treatment Research Articles

Human Umbilical Cord Mesenchymal Stem Cells Improve Lung Function in Chronic Obstructive Pulmonary Disease Rat Model Through Regulating Lung Microbiota.

The use of human umbilical cord mesenchymal stem cells (UC-MSCs) has shown promise in improving the pathophysiological characteristics of rats with chronic obstructive pulmonary disease (COPD). However, more research is needed to understand the exact mechanism behind their therapeutic effects and their impact on lung microbiota. To investigate this, rats were randomly assigned to one of 3 groups: Control, COPD + vehicle, and COPD + UC-MSCs group. Lung function changes after UC-MSCs therapy were evaluated weekly for 6 weeks. Additionally, lactate dehydrogenase (LDH), TNF (tumor necrosis factor)-α, IL (interleukin)-6, and IL-1β level in bronchoalveolar lavage fluid (BALF) were analyzed. Arterial blood gas and weight were recorded. Hematoxylin and eosin (HE) staining was used to examine lung pathology, while changes in the lung microbiota were evaluated through 16S rRNA sequencing. The administration of UC-MSCs in rats led to a progressive amelioration of COPD, as demonstrated by enhanced lung function and reduced inflammatory response. UC-MSCs treatment significantly altered the structure and diversity of the lung microbiota, effectively preventing microbiota dysbiosis. This was achieved by increasing the abundance of Bacteroidetes and reducing the levels of Proteobacteria. Additionally, treatment with UC-MSCs reduced the activation of pathways associated with COPD, including microbial metabolism, ABC transporters, and Quorum sensing. The group of UC-MSCs showed increased metabolic pathways, such as amino acid biosynthesis, purine metabolism, starch and sucrose metabolism, and biosynthesis of secondary metabolites, compared to the COPD group. The use of UC-MSCs was found to reduce inflammation and improve lung function in rats with COPD. The mechanism may be related to the lung microbiota, as UC-MSCs improved the communities of lung microbiota and regulated dysregulated metabolic pathways.

Umbilical cord mesenchymal stem cells relieve osteoarthritis in rats through immunoregulation and inhibition of chondrocyte apoptosis

This study aims to investigate the effectiveness of umbilical cord mesenchymal stem cells (UCMSCs) in treating osteoarthritis (OA). Sprague–Dawley rats were used in in vivo experiments and divided into four groups: normal, OA model, saline, and UCMSC-treated groups (n = 6). An OA model was established by injecting iodoacetic acid into the joint cavity. The results indicate that UCMSC transplantation significantly reduced joint surface and articular cartilage damage, and the levels of IL-1β, TNF-α, and MMP13 in the joint fluid were significantly reduced after UCMSC treatment. In vitro experiments showed that co-culturing UCMSCs and chondrocytes promoted the expression of aggrecan, COL2, SOX9, and BCL-2; downregulated the expression of BAX and BAD in chondrocytes; and promoted the expression of IL-10 and TGF-β1 in UCMSCs. Additionally, the supernatant of UCMSCs inhibited the expression of IL-1β and TNF-α in the articular cavity and promoted the expression of COL2 and aggrecan in vivo. These effects were impaired when IL-10 and TGF-β1 were removed. Collectively, UCMSC transplantation appears to improve joint pathology, reduce inflammatory factors, and decrease chondrocyte apoptosis, likely through the involvement of IL-10 and TGF-β1, thus providing a potential therapeutic option for patients with OA.

Human Umbilical Cord Mesenchymal Stem Cells Inhibit Pyroptosis of Renal Tubular Epithelial Cells through miR-342-3p/Caspase1 Signaling Pathway in Diabetic Nephropathy.

Diabetic nephropathy (DN) is one of the microvascular complications of diabetes. Recent studies suggest that the pyroptosis of renal tubular epithelial cell plays a critical role in DN. Currently, effective therapeutic strategies to counteract and reverse the progression of DN are lacking. Mesenchymal stem cells (MSCs) represent an attractive therapeutic tool for tissue damage and inflammation owing to their unique immunomodulatory properties. However, the underlying mechanisms remain largely unknown. In the present study, we found that human umbilical cord MSCs (UC-MSCs) can effectively ameliorate kidney damage and reduce inflammation in DN rats. Importantly, UC-MSC treatment inhibits inflammasome-mediated pyroptosis in DN. Mechanistically, we performed RNA sequencing and identified that miR-342-3p was significantly downregulated in the kidneys of DN rats. Furthermore, we found that miR-342-3p was negatively correlated with renal injury and pyroptosis in DN rats. The expression of miR-342-3p was significantly increased after UC-MSC treatment. Moreover, miR-342-3p decreased the expression of Caspase1 by targeting its 3'-UTR, which was confirmed by double-luciferase assay. Using miRNA mimic transfection, we demonstrated that UC-MSC-derived miR-342-3p inhibited pyroptosis of renal tubular epithelial cells through targeting the NLRP3/Caspase1 pathway. These findings would provide a novel intervention strategy for the use of miRNA-modified cell therapy for kidney diseases.

Clinical experience: Outcomes of mesenchymal stem cell transplantation in five stroke patients.

Stem cell therapy, which has promising results in acute disorders such as stroke, supports treatment by providing rehabilitation in the chronic stage patients. In acute stroke, thrombolytic medical treatment protocols are clearly defined in neurologic emergencies, but in neurologic patients who miss the "thrombolytic treatment intervention window," or in cases of hypoxic-ischemic encephalopathy, our hands are tied, and we are still unfortunately faced with hopeless clinical implementations. We consider mesenchymal stem cell therapy a viable option in these cases. In recent years, novel research has focused on neuro-stimulants and supportive and combined therapies for stroke. Currently, available treatment options are limited, and only certain patients are eligible for acute treatment. In the scope of our experience, five stroke patients were evaluated in this study, who was treated with a single dose of 1-2 × 106 cells/kg allogenic umbilical cord-mesenchymal stem cells (UC-MSCs) with the official confirmation of the Turkish Ministry of Health Stem Cell Commission. The patients were followed up for 12 months, and clinical outcomes are recorded. NIH Stroke Scale/Scores (NIHSS) decreased significantly (p = 0.0310), and the Rivermead Assessment Scale (RMA) increased significantly (p = 0.0234) for all patients at the end of the follow-up. All the patients were followed up for 1 year within a rehabilitation program. Major clinical outcome improvements were observed in the overall clinical conditions of the UC-MSC treatment patients. We observed improvement in the patients' upper extremity and muscle strength, spasticity, and fine motor functions. Considering recent studies in the literature together with our results, allogenic stem cell therapies are introduced as promising novel therapies in terms of their encouraging effects on physiological motor outcomes.

Human Umbilical Cord Mesenchymal Stem Cells Promote Macrophage PD-L1 Expression and Attenuate Acute Lung Injury in Mice.

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) remains a serious clinical problem but has no approved pharmacotherapy. Mesenchymal stem cells (MSCs) represent an attractive therapeutic tool for tissue damage and inflammation owing to their unique immunomodulatory properties. The present study aims to explore the therapeutic effect and underlying mechanisms of human umbilical cord MSCs (UC-MSCs) in ALI mice. In this study, we identify a novel mechanism for human umbilical cord-derived MSCs (UC-MSCs)-mediated immunomodulation through PGE2-dependent reprogramming of host macrophages to promote their PD-L1 expression. Our study suggests that UC-MSCs or primed- UC-MSCs offer new therapeutic approaches for lung inflammatory diseases. Lipopolysaccharide (LPS)-induced ALI mice were injected with 5×105 UC-MSCs via the tail vein after 4 hours of LPS exposure. After 24 hours of UC-MSC administration, the total protein concentration and cell number in the bronchoalveolar lavage fluid (BALF) and cytokine levels in the lung tissue were measured. Lung pathological changes and macrophage infiltration after UCMSC treatment were analyzed. Moreover, in vitro co-culture experiments were performed to analyze cytokine levels of RAW264.7 cells and Jurkat T cells. UC-MSC treatment significantly improved LPS-induced ALI, as indicated by decreased total protein exudation concentration and cell number in BALF and reduced pathological damage in ALI mice. UC-MSCs could inhibit pro-inflammatory cytokine levels (IL-1β, TNF-α, MCP-1, IL-2, and IFN-γ), while enhancing anti-inflammatory cytokine IL-10 expression, as well as reducing macrophage infiltration into the injured lung tissue. Importantly, UC-MSC administration increased programmed cell death protein ligand 1 (PD-L1) expression in the lung macrophages. Mechanistically, UC-MSCs upregulated cyclooxygenase-2 (COX2) expression and prostaglandin E2 (PGE2) secretion in response to LPS stimulation. UC-MSCs reduced the inflammatory cytokine levels in murine macrophage Raw264.7 through the COX2/PGE2 axis. Furthermore, UC-MSC- derived PGE2 enhanced PD-L1 expression in RAW264.7 cells, which in turn promoted programmed cell death protein 1 (PD-1) expression and reduced IL-2 and IFN-γ production in Jurkat T cells. Our results suggest that UC-MSCs attenuate ALI via PGE2-dependent reprogramming of macrophages to promote their PD-L1 expression.

UC-MSCs promote frozen-thawed ovaries angiogenesis via activation of the Wnt/β-catenin pathway in vitro ovarian culture system

BackgroundOvarian tissue cryopreservation and transplantation are novel therapeutic approaches for fertility preservation. However, follicle loss caused by ischemic and hypoxic damage is one of the issues after frozen-thawed ovarian tissue transplantation. Promoting angiogenesis in grafts is the key to restore cryopreserved ovarian function. Mesenchymal stem cells (MSCs) have been reported to facilitate angiogenesis in the cryopreserved ovarian tissue transplantation. However, the risk of embolization, immunogenic effect and tumorigenesis hinders the clinical application of MSCs to human organ transplantation. In this study, we established an in vitro ovarian culture system to restore frozen-thawed ovarian function before transplantation with the application of umbilical cord mesenchymal stem cells (UC-MSCs), and explored the effects of UC-MSCs on frozen-thawed ovaries in vitro ovarian culture system and the mechanisms of UC-MSCs on the angiogenesis of frozen-thawed ovaries.MethodsA simple in vitro three dimensional (3D) ovarian culture system using Matrigel was established to support to an ideal niche, and ovary was alone cultured in the 24-well plate as a control. We also evaluated the effects of UC-MSCs treatment on ovarian function with or without Matrigel support. All thawed ovaries were randomly divided into control group (Matrigel−/UC-MSCs−), Matrigel group (Matrigel+/UC-MSCs−), UC-MSCs group (Matrigel−/UC-MSCs+) and UC-MSCs + Matrigel group (Matrigel+/UC-MSCs+). HE staining was used to detect the histological structure of follicles and TUNEL staining was used to detect cell apoptosis. The number of microvessels was counted to evaluate neovascularization. The mRNA expression of VEGFA, IGF1 and ANGPT2 were detected by RT-PCR. Western blotting was used to measure the expression of GSK-3β, β-catenin and p-β-catenin.ResultsIn the absence of UC-MSCs, 3D culture system supported by Matrigel showed significantly improved follicular development and microvascular number. Additionally, UC-MSCs were also found to effectively improve follicular development and microvascular number regardless of the culture condition used. However, alleviated follicular apoptosis, increased mRNA expression of angiogenesis-related gene and activated Wnt/β-catenin pathway occurred only in the UC-MSCs + Matrigel group. Besides, with the application of IWP-2 in UC-MSCs + Matrigel group, Wnt//β-catenin pathway could be blocked by IWP-2 serving as one of Wnt/β-catenin pathway inhibitors.ConclusionsThis in vitro study showed the beneficial effects of UC-MSCs on thawed ovaries and explored a potential mechanism inducing angiogenesis. In particular, 3D ovarian culture system supported by Matrigel further improved UC-MSCs treatment. The in vitro culture system using Matrigel and UC-MSCs may provide a potential treatment strategy for improving the success rate of thawed ovaries transplantation.

Umbilical Cord Mesenchymal Stem Cells Ameliorate Kidney Injury in MRL/Ipr Mice Through the TGF-β1 Pathway.

The therapeutic effects and mechanism of umbilical cord mesenchymal stem cells (UC-MSC) on kidney injury in MRL/Ipr mice were studied. UC-MSC, methylprednisolone (MP), and their combination were used to treat MRL/Ipr mice. The therapeutic effects were evaluated by renal function assessment, and HE, PAS, and Masson staining were carried out on renal tissues and visualized by electron microscopy. Subsequently, podocyte injury was detected by the presence of podocin in renal tissues by immunofluorescence. To further explore the mechanism, serum TGF-β1 was measured, and TGF-β1, p-Smad3, and TRAF6 in the renal tissue were detected by Western blotting. In vitro, TGF-β1 was used to stimulate podocytes, and the podocyte activity and changes in synaptopodin were observed after UC-MSC treatment. Significant improvements in renal function and pathological injury were observed in the UC-MSC group compared to the lupus nephritis (LN) model group. UC-MSC and MP treatment improved podocyte injury in MRL/Ipr mice. Western blot examination showed a significant increase in TGF-β1, p-Smad3, and TRAF6 expression in renal tissues of the LN model group, while significant downregulation of those proteins was observed in the UC-MSC group. After TGF-β1 stimulation in vitro, podocyte activity decreased, and UC-MSC treatment improved podocyte activity and restored synaptopodin expression. UC-MSC therapy could improve the deterioration of renal function and the pathological changes of the renal tissues in MRL/Ipr mice. Our study suggested that UC-MSC may improve kidney injury and podocyte injury in LN mice by inhibiting the TGF-β1 pathway.

Human Umbilical Cord Mesenchymal Stem Cells Improve Locomotor Function in Parkinson's Disease Mouse Model Through Regulating Intestinal Microorganisms.

Parkinson’s disease (PD) is a progressive neurological disorder characterized by loss of neurons that synthesize dopamine, and subsequent impaired movement. Umbilical cord mesenchymal stem cells (UC-MSCs) exerted neuroprotection effects in a rodent model of PD. However, the mechanism underlying UC-MSC-generated neuroprotection was not fully elucidated. In the present study, we found that intranasal administration of UC-MSCs significantly alleviated locomotor deficits and rescued dopaminergic neurons by inhibiting neuroinflammation in a PD mouse model induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP, a toxic agent which selectively destroys nigrostriatal neurons but does not affect dopaminergic neurons elsewhere). Furthermore, UC-MSC treatment altered gut microbiota composition characterized by decreased phylum Proteobacteria, class Gammaproteobacteria, family Enterobacteriaceae, and genus Escherichia-Shigella. In addition, the neurotransmitter dopamine in the striatum and 5-hydroxytryptamine in the colon were also modulated by UC-MSCs. Meanwhile, UC-MSCs significantly maintained intestinal goblet cells, which secrete mucus as a mechanical barrier against pathogens. Furthermore, UC-MSCs alleviate the level of TNF-α and IL-6 as well as the conversion of NF-κB expression in the colon, indicating that inflammatory responses were blocked by UC-MSCs. PICRUSt showed that some pathways including bacterial invasion of epithelial cells, fluorobenzoate degradation, and pathogenic Escherichia coli infection were significantly reversed by UC-MSCs. These data suggest that the beneficial effects were detected following UC-MSC intranasal transplantation in MPTP-treated mice. There is a possible neuroprotective role of UC-MSCs in MPTP-induced PD mice by cross talk between the brain and gut.

Transplantation of umbilical cord-derived mesenchymal stem cells promotes the recovery of thin endometrium in rats

The endometrium plays a critical role in embryo implantation and pregnancy, and a thin uterus is recognized as a key factor in embryo implantation failure. Umbilical cord mesenchymal stem cells (UC-MSCs) have attracted interest for the repair of intrauterine adhesions. The current study investigated the repair of thin endometrium in rats using the UC-MSCs and the mechanisms involved. Rats were injected with 95% ethanol to establish a model of thin endometrium. The rats were randomly divided into normal, sham, model, and UC-MSCs groups. Endometrial morphological alterations were observed by hematoxylin–eosin staining and Masson staining, and functional restoration was assessed by testing embryo implantation. The interaction between UC-MSCs and rat endometrial stromal cells (ESCs) was evaluated using a transwell 3D model and immunocytochemistry. Microarray mRNA and miRNA platforms were used for miRNA-mRNA expression profiling. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) analyses were performed to identify the biological processes, molecular functions, cellular components, and pathways of endometrial injury and UC-MSCs transplantation repair and real-time quantitative reverse transcription PCR (qRT-PCR) was performed to further identify the expression changes of key molecules in the pathways. Endometrium thickness, number of glands, and the embryo implantation numbers were improved, and the degree of fibrosis was significantly alleviated by UC-MSCs treatment in the rat model of thin endometrium. In vitro cell experiments showed that UC-MSCs migrated to injured ESCs and enhanced their proliferation. miRNA microarray chip results showed that expression of 45 miRNAs was downregulated in the injured endometrium and upregulated after UC-MSCs transplantation. Likewise, expression of 39 miRNAs was upregulated in the injured endometrium and downregulated after UC-MSCs transplantation. The miRNA-mRNA interactions showed the changes in the miRNA and mRNA network during the processes of endometrial injury and repair. GO and KEGG analyses showed that the process of endometrial injury was mainly attributed to the decomposition of the extracellular matrix (ECM), protein degradation and absorption, and accompanying inflammation. The process of UC-MSCs transplantation and repair were accompanied by the reconstruction of the ECM, regulation of chemokines and inflammation, and cell proliferation and apoptosis. The key molecules involved in ECM-receptor interaction pathways were further verified by qRT-PCR. Itga1 and Thbs expression decreased in the model group and increased by UC-MSCs transplantation, while Laminin and Collagen expression increased in both the model group and MSCs group, with greater expression observed in the latter. This study showed that UC-MSCs transplantation could promote recovery of thin endometrial morphology and function. Furthermore, it revealed the expression changes of miRNA and mRNA after endometrial injury and UC-MSCs transplantation repair processed, and signaling pathways that may be involved in endometrial injury and repair.

The impact of recipient age on the effects of umbilical cord mesenchymal stem cells on HBV-related acute-on-chronic liver failure and liver cirrhosis

BackgroundThe results of a previous study verified that umbilical cord mesenchymal stem cells (UCMSCs) have good therapeutic effects for the treatment of HBV-related acute-on-chronic liver failure (ACLF) and liver cirrhosis (LC). Nevertheless, it is still unknown whether the effects of UCMSCs are affected by recipient age.MethodsPatients treated with UCMSCs who met the criteria of HBV-related ACLF and liver cirrhosis were identified in this retrospective observational study. Patients were divided into subgroups according to the World Health Organization (WHO) age criteria (< 45 vs. ≥ 45 years). Group A included young ACLF patients (< 45 y), and group B included older ACLF patients (≥ 45 y). Young LC patients (< 45 y) were assigned to group C, and group D included older LC patients (≥ 45 y). Patients’ clinical characteristics, demographics, biochemical factors, and model for end-stage liver disease (MELD) scores were compared for 24 weeks.ResultsSixty-four ACLF patients and 59 LC patients were enrolled in this study. Compared with patients in groups B and C, patients in group A did not show significant superiority in terms of the levels of ALT, AST, TBIL, AFP, and PTA and MELD scores. However, the median decrease and cumulative decrease in the TBIL and ALT levels of patients in group C were larger than those of patients in group D after four weeks of UCMSC transfusions. For older patients (≥ 45 y), the cumulative decrease and the median decrease in the TBIL of ACLF patients were significantly greater than those of LC patients after UCMSC treatment. However, the median decrease in ALT levels of ACLF patients was significantly greater than that of LC patients during UCMSC treatment, and the cumulative decrease in ALT levels of ACLF patients was significantly greater than that of LC patients at all time points.ConclusionThe therapeutic effects of UCMSCs for HBV-related acute-on-chronic liver failure and liver cirrhosis varied partly by patient age. Assessing patient age is necessary prior to UCMSC clinical use.

Therapeutic potential of human umbilical cord mesenchymal stem cells on aortic atherosclerotic plaque in a high-fat diet rabbit model

BackgroundAtherosclerosis (AS) is a complex disease caused in part by dyslipidemia and chronic inflammation. AS is associated with serious cardiovascular disease and remains the leading cause of mortality worldwide. Mesenchymal stem cells (MSCs) have evolved as an attractive therapeutic agent in various diseases including AS. Human umbilical cord MSCs (UCSCs) have been used in cell therapy trials due to their ability to differentiate and proliferate. The present study aimed to investigate the effect of UCSCs treatment on atherosclerotic plaque formation and the progression of lesions in a high-fat diet rabbit model.MethodsRabbits were fed a high-fat diet and then randomly divided into three groups: control, model, and treatment groups. Rabbits in the treatment group were injected with UCSCs (6 × 106 in 500 μL phosphate buffered saline) after 1 month of high-fat diet, once every 2 weeks, for 3 months. The model group was given PBS only. We analyzed serum biomarkers, used ultrasound and histopathology to detect arterial plaques and laser Doppler imaging to measure peripheral blood vessel blood filling, and analyzed the intestinal flora and metabolism.ResultsHistological analysis showed that the aortic plaque area was significantly reduced in the treatment group. We also found a significant decrease in macrophage accumulation and apoptosis, an increase in expression of scavenger receptors CD36 and SRA1, a decrease in uptake of modified low–density protein (ox-LDL), and a decrease in levels of pro-inflammatory cytokines interleukin (IL)-6 and tumor necrosis factor (TNF)-α following UCSCs treatment. We also found that anti-inflammatory cytokines IL-10 and transforming growth factor (TGF)-β expression increased in the aorta atherosclerotic plaque of the treatment group. UCSCs treatment improved the early peripheral blood filling, reduced the serum lipid level, and inhibited inflammation progression by regulating the intestinal flora dysbiosis caused by the high-fat diet. More specifically, levels of the microbiota-dependent metabolite trimethylamine-N-oxide (TMAO) were down-regulated in the treatment group.ConclusionsUCSCs treatment alleviated atherosclerotic plaque burden by reducing inflammation, regulating the intestinal flora and TMAO levels, and repairing the damaged endothelium.

Umbilical Cord-derived Mesenchymal Stem Cells modulate TNF and soluble TNF Receptor 2 (sTNFR2) in COVID-19 ARDS patients.

We aimed at explaining the mechanism of therapeutic effect of Umbilical Cord Mesenchymal Stem Cells (UC-MSC) in subjects with COVID-19 Acute Respiratory Distress Syndrome (ARDS). Patients with COVID-19 ARDS present with a hyperinflammatory response characterized by high levels of circulating pro-inflammatory mediators, including tumor necrosis factor α and β (TNFα and TNFβ). Inflammatory functions of these TNFs can be inhibited by soluble TNF Receptor 2 (sTNFR2). In patients with COVID-19 ARDS, UC-MSC appear to impart a robust anti-inflammatory effect, and treatment is associated with remarkable clinical improvements. We investigated the levels of TNFα, TNFβ and sTNFR2 in blood plasma samples collected from subjects with COVID-19 ARDS enrolled in our trial of UC-MSC treatment. We analyzed plasma samples from subjects with COVID-19 ARDS (n=24) enrolled in a Phase 1/2a randomized controlled trial of UC-MSC treatment. Plasma samples were obtained at Day 0 (baseline, before UC-MSC or control infusion), and Day 6 post infusion. Plasma concentrations of sTNFR2, TNFα, and TNFβ were evaluated using a quantitative multiplex protein array. Our data indicate that at Day 6 after infusion, UC-MSC recipients develop significantly increased levels of plasma sTNFR2 and significantly decreased levels of TNFα and TNFβ, compared to controls. These observations suggest that sTNFR2 plays a mechanistic role in mediating UC-MSC effect on TNFα and TNFβ plasma levels, determining a decrease in inflammation in COVID-19 ARDS.

Umbilical cord mesenchymal stem cells enhance the therapeutic effect of imipenem by regulating myeloid-derived suppressor cells in septic mice

BackgroundUmbilical cord mesenchymal stem cells (UC-MSCs), which possess potent immunomodulatory effects and low immunogenicity, are considered to be a promising stem cell-based therapy for sepsis. In the current study, we aimed to investigate whether the combined use of UC-MSCs and imipenem has a better effect than imipenem alone in treating Escherichia coli (E. coli)-induced sepsis and to explore the mechanism by which UC-MSCs exert their therapeutic effect in septic mice.MethodsWe randomly divided mice into five groups with 10 mice in each group: the normal control group (control group), the sepsis group (vehicle group), the MSCs treatment group (MSCs group), the imipenem treatment group (imipenem group), and the imipenem plus MSCs treatment group (imipenem + MSCs group). We monitored the survival rate in each group every 12 h for 3 days. After observing the survival rate, another 50 mice were also randomly divided into five groups, and the mice were sacrificed after 24 h. Bacterial colonies from the blood and peritoneal lavage fluid were counted in a blinded manner. Organ injury was analyzed by hematoxylin and eosin (HE) staining. Frequencies of myeloid-derived suppressor cells (MDSCs) in the blood, spleen, and bone marrow (BM) were determined by flow cytometry. Plasma levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-6, IL-1β, and IL-10 were detected by enzyme-linked immunosorbent assay (ELISA).ResultsCompared with imipenem treatment, the co-administration of UC-MSCs and imipenem dramatically improved the survival rate, decreased the bacterial load, and ameliorated organ injury. Furthermore, UC-MSCs treatment, either alone or in combination with imipenem, significantly increased plasma levels of IL-10 and the percentage of MDSCs by inducing arginase-1 in septic mice.ConclusionsOur results indicated that UC-MSCs protect mice against sepsis by acting on MDSCs. Combination therapy of UC-MSCs and imipenem may be a new approach for the future clinical treatment of sepsis.

Intra-articular injection of human umbilical cord mesenchymal stem cells ameliorates monosodium iodoacetate-induced osteoarthritis in rats by inhibiting cartilage degradation and inflammation.

AimsThis study aimed to investigate whether human umbilical cord mesenchymal stem cells (UC-MSCs) can prevent articular cartilage degradation and explore the underlying mechanisms in a rat osteoarthritis (OA) model induced by monosodium iodoacetate (MIA).MethodsHuman UC-MSCs were characterized by their phenotype and multilineage differentiation potential. Two weeks after MIA induction in rats, human UC-MSCs were intra-articularly injected once a week for three weeks. The therapeutic effect of human UC-MSCs was evaluated by haematoxylin and eosin, toluidine blue, Safranin-O/Fast green staining, and Mankin scores. Markers of joint cartilage injury and pro- and anti-inflammatory markers were detected by immunohistochemistry.ResultsHistopathological analysis showed that intra-articular injection of human UC-MSCs significantly inhibited the progression of OA, as demonstrated by reduced cartilage degradation, increased Safranin-O staining, and lower Mankin scores. Immunohistochemistry showed that human UC-MSC treatment down-regulated the expression of matrix metalloproteinase-13 (MMP13) and a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS-5), and enhanced the expression of type II collagen and ki67 in the articular cartilage. Furthermore, human UC-MSCs significantly decreased the expression of interleukin (IL)-1β and tumour necrosis factor-α (TNF-α), while increasing TNF-α-induced protein 6 and IL-1 receptor antagonist.ConclusionOur results demonstrated that human UC-MSCs ameliorate MIA-induced OA by preventing cartilage degradation, restoring the proliferation of chondrocytes, and inhibiting the inflammatory response, which implies that human UC-MSCs may be a promising strategy for the treatment of OA.Cite this article: Bone Joint Res 2021;10(3):226–236.

Effect of human umbilical cord-derived mesenchymal stem cells on lung damage in severe COVID-19 patients: a randomized, double-blind, placebo-controlled phase 2 trial

Treatment of severe Coronavirus Disease 2019 (COVID-19) is challenging. We performed a phase 2 trial to assess the efficacy and safety of human umbilical cord-mesenchymal stem cells (UC-MSCs) to treat severe COVID-19 patients with lung damage, based on our phase 1 data. In this randomized, double-blind, and placebo-controlled trial, we recruited 101 severe COVID-19 patients with lung damage. They were randomly assigned at a 2:1 ratio to receive either UC-MSCs (4 × 107 cells per infusion) or placebo on day 0, 3, and 6. The primary endpoint was an altered proportion of whole lung lesion volumes from baseline to day 28. Other imaging outcomes, 6-minute walk test (6-MWT), maximum vital capacity, diffusing capacity, and adverse events were recorded and analyzed. In all, 100 COVID-19 patients were finally received either UC-MSCs (n = 65) or placebo (n = 35). UC-MSCs administration exerted numerical improvement in whole lung lesion volume from baseline to day 28 compared with the placebo (the median difference was −13.31%, 95% CI −29.14%, 2.13%, P = 0.080). UC-MSCs significantly reduced the proportions of solid component lesion volume compared with the placebo (median difference: −15.45%; 95% CI −30.82%, −0.39%; P = 0.043). The 6-MWT showed an increased distance in patients treated with UC-MSCs (difference: 27.00 m; 95% CI 0.00, 57.00; P = 0.057). The incidence of adverse events was similar in the two groups. These results suggest that UC-MSCs treatment is a safe and potentially effective therapeutic approach for COVID-19 patients with lung damage. A phase 3 trial is required to evaluate effects on reducing mortality and preventing long-term pulmonary disability. (Funded by The National Key R&D Program of China and others. ClinicalTrials.gov number, NCT04288102.

Human umbilical cord-derived mesenchymal stem cells prevent the progression of early diabetic nephropathy through inhibiting inflammation and fibrosis

BackgroundDiabetic nephropathy (DN) is one of the most serious complications of diabetes and the leading cause of end-stage chronic kidney disease. Currently, there are no effective drugs for treating DN. Therefore, novel and effective strategies to ameliorate DN at the early stage should be identified. This study aimed to explore the effectiveness and underlying mechanisms of human umbilical cord mesenchymal stem cells (UC-MSCs) in DN.MethodsWe identified the basic biological properties and examined the multilineage differentiation potential of UC-MSCs. Streptozotocin (STZ)-induced DN rats were infused with 2 × 106 UC-MSCs via the tail vein at week 6. After 2 weeks, we measured blood glucose level, levels of renal function parameters in the blood and urine, and cytokine levels in the kidney and blood, and analyzed renal pathological changes after UC-MSC treatment. We also determined the colonization of UC-MSCs in the kidney with or without STZ injection. Moreover, in vitro experiments were performed to analyze cytokine levels of renal tubular epithelial cell lines (NRK-52E, HK2) and human renal glomerular endothelial cell line (hrGECs).ResultsUC-MSCs significantly ameliorated functional parameters, such as 24-h urinary protein, creatinine clearance rate, serum creatinine, urea nitrogen, and renal hypertrophy index. Pathological changes in the kidney were manifested by significant reductions in renal vacuole degeneration, inflammatory cell infiltration, and renal interstitial fibrosis after UC-MSC treatment. We observed that the number of UC-MSCs recruited to the injured kidneys was increased compared with the controls. UC-MSCs apparently reduced the levels of pro-inflammatory cytokines (IL-6, IL-1β, and TNF-α) and pro-fibrotic factor (TGF-β) in the kidney and blood of DN rats. In vitro experiments showed that UC-MSC conditioned medium and UC-MSC-derived exosomes decreased the production of these cytokines in high glucose-injured renal tubular epithelial cells, and renal glomerular endothelial cells. Moreover, UC-MSCs secreted large amounts of growth factors including epidermal growth factor, fibroblast growth factor, hepatocyte growth factor, and vascular endothelial growth factor.ConclusionUC-MSCs can effectively improve the renal function, inhibit inflammation and fibrosis, and prevent its progression in a model of diabetes-induced chronic renal injury, indicating that UC-MSCs could be a promising treatment strategy for DN.

Effectiveness of umbilical cord mesenchymal stem cells in patients with critical limb ischemia

Introduction and objectiveTransplantation of umbilical cord mesenchymal stem cells (UC-MSCs) has been shown to be effective in treating critical limb ischemia (CLI). However, the mechanism of MSCs-mediated improvements, especially on the immune-inflammatory aspects of this disease, is still unknown. In this study, we investigated the changes in T-lymphocyte subpopulations and inflammatory mediators (such as IL-6, IL-10 and TNF-α) in PBMCs from CLI patients after UC-MSCs treatment and correlation between inflammatory mediators and EPCs. Patients and methods8 patients received UC-MSCs transplantation. Before the treatment, at 24h and 1 month thereafter, peripheral blood samples were collected from 8 patients and 8 healthy volunteers. Patients were evaluated for changes in IL-6, IL-10, TNF-α and levels of circulating EPCs. ResultsTNF-α and IL-6 serum levels increased at 24h (p=0.017, p=0.099) after treatment and then decreased at 1 month (p=0.031, p=0.072) compared with those before treatment. The percentages of CD3+T, CD3+CD4+T-lymphocytes and NK cells decreased significantly after UC-MSCs treatment (p=0.002, p=0.012 and p=0.029, respectively). TNF-α (r=−0.602, p=0.038) was shown to be inversely correlated with the number of circulating EPCs. ConclusionsThis study demonstrates that UC-MSCs have anti-inflammatory and immunomodulation properties in CLI and suggests that UC-MSCs promote healing of non-healing wounds.

[Interference research of umbilical cord mesenchymal stem cells on the pulmonary fibrosis in silicosis rats].

Objective: To explore the effect of the umbilical cord mesenchymal stem cells(UC-MSCs) on the pulmonary fibrosis in silicosis rats. Methods: SPF male Sprague Dawley rats were randomly divided into control group, silica model group and UC-MSCs treatment group with 12 rats each group. SiO(2) intra-tracheal injection(0.5 ml of 50 mg/ml/rat) were applied to silica model group and UC-MSCs treatment groups. After that UC-MSCs treatment group received 1 ml UC-MSCs suspension (3×10(6) cells/ml) by tail vein injection on the 29th, 36th, 43th and 50th day after exposure to the first silica suspension. On the 60th and 75th day after exposure to silica suspension, all animals were examed for pulmonary CT. Then the rats were euthanized on 75th day after the first exposure to silica.Lung's histopathological examination of the rats from all the groups were carried out. The content of hydroxyproline in lungs, TGF-β1 and IL-6 in serum were examined. Results: The lung's histopathological examination showed no obvious inflammatory cell and no fibrosis in the lung tissue of the control group, there were a lot of inflammatory cell aggregation and collagen fiber deposition in silica model group, while in the UC-MSCs intervention group and treatment group, there were less inflammatory cells and collagen fiber. The rats from silica model groups had higher HYP, TGF-β1 and IL-6 than the rats from UC-MSCs treatment group and control group. Lung fields of rats in the control group were clear and no obvious high-density shadow. Different-sized granular high-density shadows or reticular fibrous shadows were found diffusely distributed in the lungs of the rats in silica model group. Lung field of rats in UC-MSCs intervention group and treatment group were less high density shadows, and more clear. Conclusion: UC-MSCs can alleviate the pulmonary fibrosis in silica model rats through regulating the secretion of some fibrosis related cytokines.

Effectiveness of umbilical cord mesenchymal stem cells in patients with critical limb ischemia

Introduction and objectiveTransplantation of umbilical cord mesenchymal stem cells (UC-MSCs) has been shown to be effective in treating critical limb ischemia (CLI). However, the mechanism of MSCs-mediated improvements, especially on the immune-inflammatory aspects of this disease, is still unknown. In this study, we investigated the changes in T-lymphocyte subpopulations and inflammatory mediators (such as IL-6, IL-10 and TNF-α) in PBMCs from CLI patients after UC-MSCs treatment and correlation between inflammatory mediators and EPCs. Patients and methods8 patients received UC-MSCs transplantation. Before the treatment, at 24h and 1 month thereafter, peripheral blood samples were collected from 8 patients and 8 healthy volunteers. Patients were evaluated for changes in IL-6, IL-10, TNF-α and levels of circulating EPCs. ResultsTNF-α and IL-6 serum levels increased at 24h (p=0.017, p=0.099) after treatment and then decreased at 1 month (p=0.031, p=0.072) compared with those before treatment. The percentages of CD3+T, CD3+CD4+T-lymphocytes and NK cells decreased significantly after UC-MSCs treatment (p=0.002, p=0.012 and p=0.029, respectively). TNF-α (r=−0.602, p=0.038) was shown to be inversely correlated with the number of circulating EPCs. ConclusionsThis study demonstrates that UC-MSCs have anti-inflammatory and immunomodulation properties in CLI and suggests that UC-MSCs promote healing of non-healing wounds.

Loss of A20 in BM-MSCs regulates the Th17/Treg balance in Rheumatoid Arthritis

Mesenchymal stem cells (MSCs) are multi-potent cells that are self-renewable and possess the potential to differentiate into multiple lineages. Several studies demonstrated that MSCs could regulate a Th17/Treg balance and could be a potential therapeutic target for Rheumatoid Arthritis (RA). A20 is highly expressed in many cell types after the stimulation of TNF-α, where it may inhibit pro-inflammatory cytokine secretion. However, the expression of A20 in BM-MSCs in RA is not fully understood. In our study, we found that A20 was decreased in RA patients’ bone marrow MSCs (BM-MSCs), and with more IL-6 secretion, the balance of Th17/Treg was broken. In CIA mice, we found a moderate A20 decrease in mice MSCs as compared with those of control group in mRNA and protein levels. However, the IL-6 expression was increased. After umbilical cord MSCs treatment, A20 and IL-6 expressions were equal to the control group. Thus, our study indicates that loss of A20 in MSCs regulates the Th17/Treg balance in RA and the regulatory role of A20 in pro-inflammatory IL-6 production could be a potential target for the transfer of MSCs in RA adoptive therapy.