BACKGROUND: The effects of human umbilical cord-derived mesenchymal stem cell (UC-MSC) treatment on coronavirus disease 2019 (COVID-19) patients have been preliminarily characterized. However, real-world data on the safety and efficacy of intravenous transfusions of MSCs in hospitalized COVID-19 patients at the convalescent stage remain to be reported. METHODS: This was a single-arm, multicenter, real-word study in which a contemporaneous external control was included as the control group. Besides, severe and critical COVID-19 patients were considered together as the severe group, given the small number of critical patients. For a total of 110 patients, 21 moderate patients and 31 severe patients were enrolled in the MSC treatment group, while 26 moderate patients and 32 severe patients were enrolled in the control group. All patients received standard treatment. The MSC treatment patients additionally received intravenous infusions of MSCs at a dose of 4 × 10 7 cells on days 0, 3, and 6, respectively. The clinical outcomes, including adverse events (AEs), lung lesion proportion on chest computed tomography, pulmonary function, 6-min walking distance (6-MWD), clinical symptoms, and laboratory parameters, were measured on days 28, 90, 180, 270, and 360 during the follow-up visits. RESULTS: In patients with moderate COVID-19, MSC treatment improved pulmonary function parameters, including forced expiratory volume in the first second (FEV1) and maximum forced vital capacity (VCmax) on days 28 (FEV1, 2.75 [2.35, 3.23] vs . 2.11 [1.96, 2.35], P  = 0.008; VCmax, 2.92 [2.55, 3.60] vs . 2.47 [2.18, 2.68], P  = 0.041), 90 (FEV1, 2.93 [2.63, 3.27] vs . 2.38 [2.24, 2.63], P  = 0.017; VCmax, 3.52 [3.02, 3.80] vs . 2.59 [2.45, 3.15], P  = 0.017), and 360 (FEV1, 2.91 [2.75, 3.18] vs . 2.30 [2.16, 2.70], P  = 0.019; VCmax,3.61 [3.35, 3.97] vs . 2.69 [2.56, 3.23], P  = 0.036) compared with the controls. In addition, in severe patients, MSC treatment notably reduced the proportion of ground-glass lesions in the whole lung volume on day 90 ( P  = 0.045) compared with the controls. No difference in the incidence of AEs was observed between the two groups. Similarly, no significant differences were found in the 6-MWD, D-dimer levels, or interleukin-6 concentrations between the MSC and control groups. CONCLUSIONS: Our results demonstrate the safety and potential of MSC treatment for improved lung lesions and pulmonary function in convalescent COVID-19 patients. However, comprehensive and long-term studies are required to confirm the efficacy of MSC treatment. TRIAL REGISTRATION Chinese Clinical Trial Registry, ChiCTR2000031430.
Humans ; COVID-19/therapy* ; Female ; Male ; Mesenchymal Stem Cell Transplantation/adverse effects* ; Middle Aged ; Adult ; Umbilical Cord/cytology* ; Mesenchymal Stem Cells/cytology* ; SARS-CoV-2 ; Aged ; Treatment Outcome

Objective To investigate the effects and underlying mechanisms of human placental chorionic plate-derived mesenchymal stem cells (hpcMSCs) on cognitive dysfunction, neuroinflammation, neuronal damage and synaptic plasticity in a mouse model of stroke. Methods A mouse model of middle cerebral artery occlusion (MCAO) was adopted. The mice were randomly divided into three groups: sham operation group, MCAO group and hpcMSCs treatment group, with seven mice in each group. The hpcMSCs treatment group received hpcMSCs transplantation on the 1st, 3rd and 10th day after MCAO. One month after MCAO, the cognitive ability of the mice was evaluated by Morris water maze and Y maze behavioral tests; the morphological changes and synaptic functions of hippocampal neurons were analyzed by HE staining, Nissl staining, Golgi staining and immunofluorescence staining techniques; the density and activation status of microglia was analyzed by Fluorescent labeling method; the levels of tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β) and IL-6 in brain tissue were analyzed by ELISA; the expressions of phosphorylated-mitogen-activated protein kinase kinase 1 (p-MEK1), phosphorylated-extracellular regulated protein kinase (p-ERK) and phosphorylated-cAMP-response element binding protein (p-CREB) and other proteins related to neuroprotection in the signal pathways were detected by Western blotting; and electrophysiological detection was performed using hippocampal slices in vitro. Results Compared with the MCAO group, mice in the hpcMSCs treatment group showed significant improvements, including improved cognitive ability, alleviated neuroinflammation (demonstrated by reduced microglial activation and decreased levels of inflammatory factors TNF-α, IL-1β and IL-6), and increased neuronal density with normalized morphology of neurons in the hippocampal CA1 region. The treatment group also demonstrated a significantly increased number of Nissl-positive cells and density of dendritic spines of hippocampal neurons, along with restored frequency of miniature excitatory postsynaptic potential (mEPSP). Moreover, hpcMSCs treatment significantly increased the expression levels of p-MEK1, p-ERK and p-CREB in the hippocampus. Conclusion Transplantation of hpcMSCs ameliorates cognitive dysfunction and hippocampal neuronal injury in stroke mice through the reduction of neuroinflammation, restoration of hippocampal neuronal function, promotion of synaptic plasticity and activation of the MEK/ERK/CREB signaling pathway. These findings suggest a new potential therapeutic approach for post-stroke neural repair.
Animals ; Hippocampus/physiopathology* ; Mice ; Cognitive Dysfunction/etiology* ; Mesenchymal Stem Cell Transplantation ; Male ; Neurons/metabolism* ; Stroke/metabolism* ; Humans ; Neuroinflammatory Diseases/therapy* ; Female ; Cyclic AMP Response Element-Binding Protein/metabolism* ; Disease Models, Animal ; Mesenchymal Stem Cells/cytology* ; Mice, Inbred C57BL

Stem cell treatment may enhance erectile dysfunction (ED) in individuals with cavernous nerve injury (CNI). Nevertheless, no investigations have directly ascertained the implications of varying amounts of human umbilical cord-derived mesenchymal stem cells (HUC-MSCs) on ED. We compare the efficacy of three various doses of HUC-MSCs as a therapeutic strategy for ED. Sprague-Dawley rats (total = 175) were randomly allocated into five groups. A total of 35 rats underwent sham surgery and 140 rats endured bilateral CNI and were treated with vehicles or doses of HUC-MSCs (1 × 10 6 cells, 5 × 10 6 cells, and 1 × 10 7 cells in 0.1 ml, respectively). Penile tissues were harvested for histological analysis on 1 day, 3 days, 7 days, 14 days, 28 days, 60 days, and 90 days postsurgery. It was found that varying dosages of HUC-MSCs enhanced the erectile function of rats with bilateral CNI and ED. Moreover, there was no significant disparity in the effectiveness of various dosages of HUC-MSCs. However, the expression of endothelial markers (rat endothelial cell antigen-1 [RECA-1] and endothelial nitric oxide synthase [eNOS]), smooth muscle markers (alpha smooth muscle actin [α-SMA] and desmin), and neural markers (neurofilament [RECA-1] and neurogenic nitric oxide synthase [nNOS]) increased significantly with prolonged treatment time. Masson's staining demonstrated an increased in the smooth muscle cell (SMC)/collagen ratio. Significant changes were detected in the microstructures of various types of cells. In vivo imaging system (IVIS) analysis showed that at the 1 st day, the HUC-MSCs implanted moved to the site of damage. Additionally, the oxidative stress levels were dramatically reduced in the penises of rats administered with HUC-MSCs.
Male ; Animals ; Erectile Dysfunction/metabolism* ; Rats, Sprague-Dawley ; Mesenchymal Stem Cell Transplantation/methods* ; Rats ; Penis/pathology* ; Humans ; Disease Models, Animal ; Umbilical Cord/cytology* ; Peripheral Nerve Injuries/complications* ; Mesenchymal Stem Cells ; Nitric Oxide Synthase Type III/metabolism* ; Actins/metabolism* ; Nitric Oxide Synthase Type I/metabolism*

This report describes two cases of severe immune-mediated thrombocytopenia after allogeneic hematopoietic stem cell transplantation (HSCT) who were treated with umbilical cord mesenchymal stem cells (UC-MSCs). Case 1 was a child with severe aplastic anemia who underwent haploidentical bone marrow and peripheral blood HSCT, with a chimerism rate of 99.8% on day +25 and severe immune-mediated thrombocytopenia on day +60. After intravenous immunoglobulin (IVIG) pulse therapy, platelet count increased temporarily but then decreased, while cyclosporine, methylprednisolone, and rituximab had a poor therapeutic effect. Case 2 was a child with Gaucher's disease who underwent unrelated umbilical cord blood HSCT, with a chimerism rate of 96.35% on day +41 and severe immune-mediated thrombocytopenia on day +153. After three sessions of IVIG pulse therapy, the platelet count increased initially but subsequently decreased. Therapies with dexamethasone, prednisone, cyclosporine, and recombinant human thrombopoietin also yielded a poor response. Both children received three sessions of UC-MSCs infusion, and platelet counts increased and were subsequently maintained within the normal range. Case 1 has been followed up for 10 years and remains in disease-free survival. UC-MSCs infusion may be effective for severe immune-mediated thrombocytopenia that is unresponsive to first- and second-line therapies after HSCT and could potentially improve the quality of life and disease-free survival rate.
Child ; Humans ; Hematopoietic Stem Cell Transplantation/adverse effects* ; Mesenchymal Stem Cell Transplantation ; Purpura, Thrombocytopenic, Idiopathic/etiology* ; Thrombocytopenia/therapy* ; Transplantation, Homologous ; Umbilical Cord/cytology*

OBJECTIVES: To investigate whether human umbilical cord mesenchymal stem cells (HUC-MSCs) play protective effects against white matter injury (WMI) in neonatal rats via activation of the nuclear factor-erythroid 2-related factor 2 (Nrf2)/Kelch-like ECH-associated protein 1 (Keap1)/heme oxygenase-1 (HO-1) signaling pathway. METHODS: A neonatal WMI model was established in 3-day-old Sprague-Dawley rats by unilateral common carotid artery ligation combined with hypoxia. The study comprised two parts. (1) Rats were randomized into sham, hypoxia-ischemia (HI), and HUC-MSC groups (n=36 per group); brain tissues were collected at 7, 14, and 21 days after modeling. (2) Rats were randomized into sham, HI, HUC-MSC, and HUC-MSC+ML385 (Nrf2 inhibitor) groups (n=12 per group); tissues were collected 14 days after modeling. Hematoxylin-eosin staining assessed histopathology, and Luxol fast blue staining evaluated myelination. Immunohistochemistry examined the localization and expression of Nrf2, myelin basic protein (MBP), and proteolipid protein (PLP). Immunofluorescence assessed synaptophysin (SYP) and postsynaptic density-95 (PSD-95). Western blotting quantified Nrf2, Keap1, HO-1, SYP, PSD-95, MBP, and PLP. Spatial learning and memory were evaluated by the Morris water maze. RESULTS: At 7, 14, and 21 days after modeling, the sham group showed intact white matter, whereas the HI group exhibited white matter disruption, cellular vacuolation, and disorganized nerve fibers. These pathological changes were attenuated in the HUC-MSC group. Compared with the HI group, the HUC-MSC group showed increased Nrf2 immunopositivity and protein levels, increased HO-1 protein levels, and decreased Keap1 protein levels (P<0.05). Compared with the HI group, the HUC-MSC group had higher SYP and PSD-95 immunofluorescence intensities and protein levels, higher MBP and PLP positivity and protein levels, increased mean optical density of myelin, more platform crossings, and longer time in the target quadrant (all P<0.05). These improvements were reduced in the HUC-MSC+ML385 group compared with the HUC-MSC group (P<0.05). CONCLUSIONS HUC-MSCs may promote oligodendrocyte maturation and synaptogenesis after neonatal WMI by activating the Nrf2/Keap1/HO-1 pathway, thereby improving spatial cognitive function.
NF-E2-Related Factor 2/physiology* ; Animals ; Rats, Sprague-Dawley ; Signal Transduction/physiology* ; Humans ; Rats ; White Matter/pathology* ; Kelch-Like ECH-Associated Protein 1/physiology* ; Umbilical Cord/cytology* ; Heme Oxygenase-1/physiology* ; Animals, Newborn ; Male ; Mesenchymal Stem Cell Transplantation ; Heme Oxygenase (Decyclizing)/physiology* ; Mesenchymal Stem Cells/physiology* ; Female ; Hypoxia-Ischemia, Brain

OBJECTIVE: To investigate the mechanism of human embryonic stem cell-derived mesenchymal stem cells (hESC-MSC) in alleviating brain injury after resuscitation in swine with cardiac arrest (CA). METHODS: Twenty-nine healthy male large white swine were randomly divided into Sham group (n = 9), cardiopulmonary resuscitation (CPR) group (n = 10) and hESC-MSC group (n = 10). The Sham group only completed animal preparation. In CPR group and hESC-MSC group, the swine model of CA-CPR was established by inducing ventricular fibrillation for 10 minutes with electrical stimulation and CPR for 6 minutes. At 5 minutes after successful resuscitation, hESC-MSC 2.5×10⁶/kg was injected via intravenous micropump within 1 hour in hESC-MSC group. Venous blood samples were collected before resuscitation and at 4, 8, 24, 48 and 72 hours of resuscitation. The levels of neuron specific enolase (NSE) and S100B protein (S100B) were detected by enzyme linked immunosorbent assay (ELISA). At 24, 48 and 72 hours of resuscitation, neurological deficit score (NDS) and cerebral performance category (CPC) were used to evaluate the neurological function of the animals. Three animals from each group were randomly selected and euthanized at 24, 48, and 72 hours of resuscitation, and the hippocampus tissues were quickly obtained. Immunofluorescence staining was used to detect the distribution of hESC-MSC in hippocampus. Immunohistochemical staining was used to detect the activation of astrocytes and microglia and the survival of neurons in the hippocampus. The degree of apoptosis was detected by TdT-mediated dUTP nick end labeling (TUNEL). RESULTS: The serum NSE and S100B levels of brain injury markers in CPR group and hESC-MSC group were significantly higher than those in Sham group at 24 hours of resuscitation, and then gradually increased. The levels of NSE and S100B in serum at each time of resuscitation in hESC-MSC group were significantly lower than those in CPR group [NSE (μg/L): 20.69±3.62 vs. 28.95±3.48 at 4 hours, 27.04±5.56 vs. 48.59±9.22 at 72 hours; S100B (μg/L): 2.29±0.39 vs. 3.60±0.73 at 4 hours, 2.38±0.15 vs. 3.92±0.50 at 72 hours, all P < 0.05]. In terms of neurological function, compared with the Sham group, the NDS score and CPC score in the CPR group and hESC-MSC group increased significantly at 24 hours of resuscitation, and then gradually decreased. The NDS and CPC scores of hESC-MSC group were significantly lower than those of CPR group at 24 hours of resuscitation (NDS: 111.67±20.21 vs. 170.00±21.79, CPC: 2.33±0.29 vs. 3.00±0.00, both P < 0.05). The expression of hESC-MSC positive markers CD73, CD90 and CD105 in the hippocampus of hESC-MSC group at 24, 48 and 72 hours of resuscitation was observed under fluorescence microscope, indicating that hESC-MSC could homing to the damaged hippocampus. In addition, compared with Sham group, the proportion of astrocytes, microglia and apoptotic index in hippocampus of CPR group were significantly increased, and the proportion of neurons was significantly decreased at 24, 48 and 72 hours of resuscitation. Compared with CPR group, the proportion of astrocytes, microglia and apoptotic index in hippocampus of hESC-MSC group decreased and the proportion of neurons increased significantly at 24 hours of resuscitation [proportion of astrocytes: (14.33±1.00)% vs. (30.78±2.69)%, proportion of microglia: (12.00±0.88)% vs. (27.89±5.68)%, apoptotic index: (12.89±3.86)% vs. (52.33±7.77)%, proportion of neurons: (39.44±3.72)% vs. (28.33±1.53)%, all P < 0.05]. CONCLUSIONS Application of hESC-MSC at the early stage of resuscitation can reduce the brain injury and neurological dysfunction after resuscitation in swine with CA. The mechanism may be related to the inhibition of immune cell activation, reduction of cell apoptosis and promotion of neuronal survival.
Animals ; Heart Arrest/therapy* ; Cardiopulmonary Resuscitation ; Swine ; Humans ; Male ; Human Embryonic Stem Cells/cytology* ; Mesenchymal Stem Cell Transplantation ; Mesenchymal Stem Cells/cytology* ; Phosphopyruvate Hydratase/blood* ; Brain Injuries/therapy* ; S100 Calcium Binding Protein beta Subunit ; Apoptosis ; Disease Models, Animal

OBJECTIVE: To compare the therapeutic efficacy of portal and tail vein transplantation of bone marrow-derived mesenchymal stem cells (BMSCs) against cholestatic liver fibrosis in mice. METHODS: BMSCs were isolated and co-cultured with starvation-activated hepatic stellate cells (HSCs). HSC activation markers were identified using immunofluorescence and qRT-PCR. BMSCs were injected into the liver tissues of bile duct ligation (BDL) mice via the tail and portal veins. Histomorphology, liver function, inflammatory cytokines, and the expression of key proteins were all determined in the liver tissues. RESULTS: BMSCs inhibited HSC activation by reducing α-SMA and collagen I expression. Compared to tail vein injection, DIL-labeled BMSCs injected through the portal vein maintained a high homing rate in the liver. Moreover, BMSCs transplanted through the portal vein resulted in greater improvement in liver color, hardness, and gallbladder size than did those transplanted through the tail vein. Furthermore, BMSCs injected by portal vein, but not tail vein, markedly ameliorated liver function, reduced the secretion of inflammatory cytokines, including TNF-α, IL-6, and IL-1β, and decreased α-SMA + hepatic stellate cell (HSC) activation and collagen fiber formation. CONCLUSION The therapeutic effect of BMSCs on cholestatic liver fibrosis in mice via portal vein transplantation was superior to that of tail vein transplantation. This comparative study provides reference information for further BMSC studies focused on clinical cholestatic liver diseases.
Animals ; Mice ; Mesenchymal Stem Cell Transplantation ; Liver Cirrhosis/etiology* ; Male ; Cholestasis/therapy* ; Mice, Inbred C57BL ; Hepatic Stellate Cells ; Mesenchymal Stem Cells

Mesenchymal stem cells (MSCs) are an effective therapeutic strategy to delay aging in dogs, they are prone to aging and have poor genetic stability when cultured for a long time in vitro. Therefore, it is of great significance to explore a method to improve the anti-aging ability of MSCs. Previous studies have shown that sirtuin 6 (SIRT6) plays an important role in anti-aging. This study constructed MSCs with overexpressed SIRT6 gene. Through Giemsa staining and senescence-associated β-galactosidase staining, it was found that SIRT6 significantly enhances the anti-aging capacity of MSCs. Transmission electron microscopy imaging and the detection of oxidative stress-related indicators revealed that SIRT6 improves the anti-aging capacity of MSCs by maintaining mitochondrial homeostasis and reducing oxidative stress levels. Transcriptome sequencing analysis revealed that SIRT6 mainly acted on phosphatidylinositol-3-kinase, mitogen-activated protein kinase and other aging and inflammation related pathways. In the establishment and verification of aging models in mice and dogs, it was found that the spatial memory ability of the model mice was significantly increased after intravenous transplantation of SIRT6 overexpression cells, the organ index was also significantly changed, and the anti-oxidative capacity of the dogs and mice blood was improved. The morphology of the spleens and livers in the SIRT6 overexpression cell treatment group could be effectively restored, and the expression levels of aging and inflammation-related proteins were significantly decreased. This study provides a new idea for the study of SIRT6-mediated anti-aging of MSCs.
Animals ; Dogs ; Mesenchymal Stem Cells/metabolism* ; Sirtuins/genetics* ; Aging/physiology* ; Mice ; Oxidative Stress ; Mesenchymal Stem Cell Transplantation

Liver disease involves a complex interplay of pathological processes, including inflammation, hepatocyte necrosis, and fibrosis. End-stage liver disease (ESLD), such as liver failure and decompensated cirrhosis, has a high mortality rate, and liver transplantation is the only effective treatment. However, to overcome problems such as the shortage of donor livers and complications related to immunosuppression, there is an urgent need for new treatment strategies that need to be developed for patients with ESLD. For instance, hepatocytes derived from donor livers or stem cells can be engrafted and multiplied in the liver, substituting the host hepatocytes and rebuilding the liver parenchyma. Stem cell therapy, especially mesenchymal stem cell therapy, has been widely proved to restore liver function and alleviate liver injury in patients with severe liver disease, which has contributed to the clinical application of cell therapy. In this review, we discussed the types of cells used to treat ESLD and their therapeutic mechanisms. We also summarized the progress of clinical trials around the world and provided a perspective on cell therapy.
Humans ; Cell- and Tissue-Based Therapy/methods* ; End Stage Liver Disease/therapy* ; Hepatocytes ; Mesenchymal Stem Cell Transplantation ; Stem Cell Transplantation

OBJECTIVE: To review the research progress on bone repair biomaterials with the function of recruiting endogenous mesenchymal stem cells (MSCs). METHODS: An extensive review of the relevant literature on bone repair biomaterials, particularly those designed to recruit endogenous MSCs, was conducted, encompassing both domestic and international studies from recent years. The construction methods and optimization strategies for these biomaterials were summarized. Additionally, future research directions and focal points concerning this material were proposed. RESULTS: With the advancement of tissue engineering technology, bone repair biomaterials have increasingly emerged as an ideal solution for addressing bone defects. MSCs serve as the most critical "seed cells" in bone tissue engineering. Historically, both MSCs and their derived exosomes have been utilized in bone repair biomaterials; however, challenges such as limited sources of MSCs and exosomes, low survival rates, and various other issues have persisted. To address these challenges, researchers are combining growth factors, bioactive peptides, specific aptamers, and other substances with biomaterials to develop constructs that facilitate stem cell recruitment. By optimizing mechanical properties, promoting vascular regeneration, and regulating the microenvironment, it is possible to create effective bone repair biomaterials that enhance stem cell recruitment. CONCLUSION In comparison to cytokines, phages, and metal ions, bioactive peptides and aptamers obtained through screening exhibit more specific and targeted recruitment functions. Future development directions for bone repair biomaterials will involve the modification of peptides and aptamers with targeted recruitment capabilities in biological materials, as well as the optimization of the mechanical properties of these materials to enhance vascular regeneration and adjust the microenvironment.
Mesenchymal Stem Cells/metabolism* ; Biocompatible Materials/chemistry* ; Tissue Engineering/methods* ; Humans ; Bone Regeneration ; Tissue Scaffolds/chemistry* ; Animals ; Bone and Bones ; Mesenchymal Stem Cell Transplantation/methods* ; Exosomes/metabolism* ; Intercellular Signaling Peptides and Proteins/metabolism* ; Osteogenesis