Mesenchymal stem cells (MSCs) have been officially approved in many countries to treat graft-versus-host disease, autoimmune disorders and those associated with tissue regeneration after hematopoietic stem cell transplantation. Studies in recent years have confirmed that MSC acts mainly through paracrine mechanism, in which extracellular vesicles secreted by MSC (MSC-EV) play a central role. MSC-EV has overwhelming advantages over MSC itself in the setting of adverse effects in clinical application, indicating that MSC-EV might take the place of its parent cells to be a potentially therapeutic tool for "cell-free therapy". The pharmaceutical properties of MSC-EV largely depend upon the practical and optimal techniques including large-scale expansion of MSC, the modification of MSC based on the indications and the in vivo dynamic features of MSC-EV, and the methods for preparing and harvesting large amounts of MSC-EV. The recent progresses on the issues above will be briefly reviewed.
Humans ; Extracellular Vesicles ; Hematopoietic Stem Cell Transplantation/adverse effects* ; Mesenchymal Stem Cell Transplantation/methods* ; Mesenchymal Stem Cells ; Pharmaceutical Preparations

OBJECTIVE: To analyze the prognostic factors of haplo-HSCT combined with MSC in the treatment of SAA. METHODS: 127 SAA patients who had undergone haplo-HSCT with co-infusion of MSC in our center from January 2014 to August 2019 were analyzed retrospectively. Median age was 11 (1-37) years, and median follow-up time was 39.8 (1-74) months. RESULTS: The median time for neutrophil and platelet engraftment was 14 d and 18 d respectively. The cumulative incidences of grade III-IV aGVHD was 4.4%±1.9% at day +100. The 2-year cumulative incidence of extensive cGVHD was 8.3%± 2.7%. The estimated 3-year OS was 86.1%±3.1%. Univariate analysis showed that high-dose CD34⁺ cells (>6.69×106/kg) could promote the engraftment of neutrophil (97.9%±0.05% vs 88.6%±0.13% at day +21, P=0.0006) and platelet (81.2%±0.33% vs 70.8%±0.26% at day +28, P=0.002) and did not increase the incidence of aGVHD (10.4%±0.1% vs 18.9%±0.1% at day +100, P=0.18). More nucleated cells (>12.78×10⁸/kg) caused a lower incidence of grade II-IV aGVHD (8.6%±0.13% vs 21.7%±0.25% at day+100, P=0.04) and a higher incidence of 3-year OS (91.3%±3.2% vs 78.1%±6.5%, P=0.03) than less nucleated cells (≤12.78×10⁸/kg). Younger patients (age≤12 y) had faster neutrophil engraftment (94.9%±0.06% vs 87.5%±0.24% at day+21, P=0.02), higher 3-year OS (93.6%±2.8% vs 75.9%±6.4%, P=0.006) and higher 3-year FFS (93.6%±2.8% vs 68.3%±7.1%, P=0.000) than older patients (age>12 y). The shorter the time from diagnosis to HSCT (≤29.5 months), the higher the 3-year FFS of patients (88.8%±3.5% vs 74.2%±7.2%, P=0.028). Male patients with female donors had higher cumulative incidence of extensive cGVHD than others (20.0%±0.8% vs 4.6%±0.1%, P=0.01). CONCLUSION In the haplo-HSCT of SAA, the prognosis of children patients is better than that of adults patients. More CD34⁺ cells and nucleated cells can promote engraftment, reduce the incidence of aGVHD and improve OS. HSCT should be performed as early as possible, and the occurrence of cGVHD should be reduced in male patients by avoiding female donors.
Adult ; Anemia, Aplastic/therapy* ; Child ; Female ; Graft vs Host Disease ; Hematopoietic Stem Cell Transplantation/adverse effects* ; Humans ; Male ; Mesenchymal Stem Cells ; Retrospective Studies ; Transplantation Conditioning/adverse effects* ; Treatment Outcome

Severe graft-versus-host disease (GVHD) is an often lethal complication of allogeneic hematopoietic stem cell transplantation (HSCT). The safety of clinical-grade mesenchymal stem cells (MSCs) has been validated, but mixed results have been obtained due to heterogeneity of the MSCs. In this phase I study, the safety of bone marrow-derived homogeneous clonal MSCs (cMSCs) isolated by a new subfractionation culturing method was evaluated. cMSCs were produced in a GMP facility and intravenously administered to patients who had refractory GVHD to standard treatment resulting after allogeneic HSCT for hematologic malignancies. After administration of a single dose (1x10(6) cells/kg), 11 patients were evaluated for cMSC treatment safety and efficacy. During the trial, nine patients had 85 total adverse events and the rate of serious adverse events was 27.3% (3/11 patients). The only one adverse drug reaction related to cMSC administration was grade 2 myalgia in one patient. Treatment response was observed in four patients: one with acute GVHD (partial response) and three with chronic GVHD. The other chronic patients maintained stable disease during the observation period. This study demonstrates single cMSC infusion to have an acceptable safety profile and promising efficacy, suggesting that we can proceed with the next stage of the clinical trial.
Bone Marrow ; Drug-Related Side Effects and Adverse Reactions ; Graft vs Host Disease* ; Hematologic Neoplasms ; Hematopoietic Stem Cell Transplantation ; Humans ; Mesenchymal Stromal Cells* ; Myalgia ; Population Characteristics

Currently, the most effective treatment for end-stage liver fibrosis is liver transplantation; however, transplantation is limited by a shortage of donor organs, surgical complications, immunological rejection, and high medical costs. Recently, mesenchymal stem cell (MSC) therapy has been suggested as an effective alternate approach for the treatment of hepatic diseases. MSCs have the potential to differentiate into hepatocytes, and therapeutic value exists in their immune-modulatory properties and secretion of trophic factors, such as growth factors and cytokines. In addition, MSCs can suppress inflammatory responses, reduce hepatocyte apoptosis, increase hepatocyte regeneration, regress liver fibrosis and enhance liver functionality. Despite these advantages, issues remain; MSCs also have fibrogenic potential and the capacity to promote tumor cell growth and oncogenicity. This paper summarizes the properties of MSCs for regenerative medicine and their therapeutic mechanisms and clinical application in the treatment of liver fibrosis. We also present several outstanding risks, including their fibrogenic potential and their capacity to promote pre-existing tumor cell growth and oncogenicity.
Animals ; Cell Differentiation ; Cell Proliferation ; Hepatocytes/immunology/metabolism/pathology/*transplantation ; Humans ; Liver/immunology/metabolism/pathology/physiopathology/*surgery ; Liver Cirrhosis/diagnosis/immunology/metabolism/physiopathology/*surgery ; Liver Regeneration ; *Mesenchymal Stem Cell Transplantation/adverse effects ; *Mesenchymal Stromal Cells/immunology/metabolism/pathology ; Phenotype ; Regenerative Medicine/*methods ; Risk Factors ; Signal Transduction ; Treatment Outcome

Based on their ability to differentiate into multiple cell types including hepatocytes, the transplantation of mesenchymal stem cells (MSCs) has been suggested as an effective therapy for chronic liver diseases. The aim of this study was to evaluate the safety, efficacy and therapeutic effects of MSCs in patients with chronic liver disease through a literature-based examination. We performed a systematic review (SR) and meta-analysis (MA) of the literature using the Ovid-MEDLINE, EMBASE and Cochrane Library databases (up to November 2014) to identify clinical studies in which patients with liver diseases were treated with MSC therapy. Of the 568 studies identified by the initial literature search, we analyzed 14 studies and 448 patients based on our selection criteria. None of the studies reported the occurrence of statistically significant adverse events, side effects or complications. The majority of the analyzed studies showed improvements in liver function, ascites and encephalopathy. In particular, an MA showed that MSC therapy improved the total bilirubin level, the serum albumin level and the Model for End-stage Liver Disease (MELD) score after MSC treatment. Based on these results, MSC transplantation is considered to be safe for the treatment of chronic liver disease. However, although MSCs are potential therapeutic agents that may improve liver function, in order to obtain meaningful insights into their clinical efficacy, further robust clinical studies must be conducted to evaluate the clinical outcomes, such as histological improvement, increased survival and reduced liver-related complications, in patients with chronic liver disease.
Cell Differentiation/physiology ; Cell- and Tissue-Based Therapy/adverse effects/*methods ; Hepatocytes/cytology ; Humans ; Liver/physiopathology/surgery ; Liver Diseases/*therapy ; Liver Function Tests ; Mesenchymal Stem Cell Transplantation/adverse effects/*methods ; Mesenchymal Stromal Cells/*cytology

Recent studies suggest that the intracoronary administration of bone marrow (BM)-derived mesenchymal stem cells (MSCs) may improve left ventricular function in patients with acute myocardial infarction (AMI). However, there is still argumentative for the safety and efficacy of MSCs in the AMI setting. We thus performed a randomized pilot study to investigate the safety and efficacy of MSCs in patients with AMI. Eighty patients with AMI after successful reperfusion therapy were randomly assigned and received an intracoronary administration of autologous BM-derived MSCs into the infarct related artery at 1 month. During follow-up period, 58 patients completed the trial. The primary endpoint was changes in left ventricular ejection fraction (LVEF) by single-photon emission computed tomography (SPECT) at 6 month. We also evaluated treatment-related adverse events. The absolute improvement in the LVEF by SPECT at 6 month was greater in the BM-derived MSCs group than in the control group (5.9%+/-8.5% vs 1.6%+/-7.0%; P=0.037). There was no treatment-related toxicity during intracoronary administration of MSCs. No significant adverse cardiovascular events occurred during follow-up. In conclusion, the intracoronary infusion of human BM-derived MSCs at 1 month is tolerable and safe with modest improvement in LVEF at 6-month follow-up by SPECT. (ClinicalTrials.gov registration number: NCT01392105)
Adult ; Aged ; Bone Marrow Cells/cytology ; Cell- and Tissue-Based Therapy/*adverse effects ; Echocardiography ; Female ; Heart/physiopathology ; Humans ; Male ; Mesenchymal Stem Cell Transplantation/*adverse effects ; Mesenchymal Stromal Cells/*cytology ; Middle Aged ; Myocardial Infarction/*therapy ; Pilot Projects ; Stroke Volume ; Tomography, Emission-Computed, Single-Photon ; Transplantation, Autologous ; Treatment Outcome ; Ventricular Function, Left ; Young Adult

BACKGROUNDRadiation-induced injury after accidental or therapeutic total body exposure to ionizing radiation has serious pathophysiological consequences, and currently no effective therapy exists. This study was designed to investigate whether transplantation of allogeneic murine compact bone derived-mesenchymal stem cells (CB-MSCs) could improve the survival of mice exposed to lethal dosage total body irradiation (TBI), and to explore the potential immunoprotective role of MSCs.

METHODSBALB/c mice were treated with 8 Gy TBI, and then some were administered CB-MSCs isolated from C57BL/6 mice. Survival rates and body weight were analyzed for 14 days post-irradiation. At three days post-irradiation, we evaluated IFN-γ and IL-4 concentrations; CD4(+)CD25(+)Foxp3(+) regulatory T cell (Treg) percentage; CXCR3, CCR5, and CCR7 expressions on CD3(+) T cells; and splenocyte T-bet and GATA-3 mRNA levels. CB-MSC effects on bone marrow hemopoiesis were assessed via colony-forming unit granulocyte/macrophage (CFU-GM) assay.

RESULTSAfter lethal TBI, compared to non-transplanted mice, CB-MSC-transplanted mice exhibited significantly increased survival, body weight, and CFU-GM counts of bone marrow cells (P < 0.05), as well as higher Treg percentages, reduced IFN-γ, CXCR3 and CCR5 down-regulation, and CCR7 up-regulation. CB-MSC transplantation suppressed Th1 immunity. Irradiated splenocytes directly suppressed CFU-GM formation from bone marrow cells, and CB-MSC co-culture reversed this inhibition.

CONCLUSIONAllogeneic CB-MSC transplantation attenuated radiation-induced hematopoietic toxicity, and provided immunoprotection by alleviating lymphocyte-mediated CFU-GM inhibition, expanding Tregs, regulating T cell chemokine receptor expressions, and skewing the Th1/Th2 balance toward anti-inflammatory Th2 polarization.

Animals ; Bone and Bones ; cytology ; Cytokines ; metabolism ; Female ; Granulocyte-Macrophage Progenitor Cells ; cytology ; Male ; Mesenchymal Stem Cell Transplantation ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Whole-Body Irradiation ; adverse effects

The therapeutic potential of human multipotent mesenchymal stromal cells, especially human adipose tissue-derived stem cells (hASC), is promising. However, there are concerns about the safety of infusion of hASC in human. Recently, we have experienced pulmonary embolism and infarct among family members who have taken multiple infusions of intravenous autologous hASC therapy. A 41-year-old man presented with chest pain for one month. Chest CT showed multiple pulmonary artery embolism and infarct at right lung. Serum D-dimer was 0.8 microg/mL (normal; 0-0.5 microg/mL). He had received intravenous autologous adipose tissue-derived stem cell therapy for cervical herniated intervertebral disc three times (one, two, and three months prior to the visit). His parents also received the same therapy five times and their chest CT also showed multiple pulmonary embolism. These cases represent artificial pulmonary embolisms and infarct after IV injection of hASC. Follow-up chest CT showed spontaneous resolution of lesions in all three patients.
Adipose Tissue/cytology ; Adult ; Cell- and Tissue-Based Therapy/*adverse effects ; Female ; Humans ; Male ; Mesenchymal Stem Cell Transplantation/*adverse effects ; Pulmonary Embolism/*etiology/radiography ; Pulmonary Infarction/etiology/radiography ; Tomography, X-Ray Computed

This study was aimed to investigate the curative effect and safety of human umbilical cord mesenchymal stem cells (hUCMSC) to treat acute graft-versus-host disease (aGVHD) of children after hematopoietic stem cell transplantation (HSCT). HUCMSC were isolated and cultured by collagenase digestion and passage culture. The 3rd to the 5th passage of hUCMSC were used for clinical treatment. Five cases of children acute leukemia achieved complete remission after chemotherapy. Two cases received HLA 3/6 loci matched haploidentical bone marrow HSCT. One case received HLA-matched sibling bone marrow and peripheral blood HSCT. One case received unrelated HLA 4/6 loci matched umbilical cord blood HSCT. One case received unrelated HLA 5/6 loci matched umbilical cord blood HSCT. The children received immunosuppressive therapy after III-IV aGVHD occurring. They received 0.5×10(6)/kg hUCMSC infusion when conventional therapy was ineffective. The results showed that 5 cases of children acute leukemia achieved hematopoietic reconstitution and developed the III-IV grade aGVHD. The five cases of children were infused with hUCMSC. The rash subsided, the liver function was normalized and the gastrointestinal symptoms were improved. The infusion-related adverse reaction did not happen. At present, the 5 children are in remission. It is concluded that allogeneic HSCT is an effective therapeutic method for children with acute leukemia. HUCMSC infusion can be safely and effectively used for the treatment of refractory aGVHD.
Child ; Child, Preschool ; Cord Blood Stem Cell Transplantation ; Female ; Graft vs Host Disease ; therapy ; Hematopoietic Stem Cell Transplantation ; adverse effects ; Humans ; Male ; Mesenchymal Stem Cell Transplantation ; Treatment Outcome

Mesenchymal stem cells (MSCs) are self-renewing, multipotent progenitor cells with multilineage potential to differentiate into cell types of mesodermal origin, such as adipocytes, osteocytes, and chondrocytes. In addition, MSCs can migrate to sites of inflammation and exert potent immunosuppressive and anti-inflammatory effects through interactions between lymphocytes associated with both the innate and adaptive immune system. Along with these unique therapeutic properties, their ease of accessibility and expansion suggest that use of MSCs may be a useful therapeutic approach for various disorders. In the clinical setting, MSCs are being explored in trials of various conditions, including orthopedic injuries, graft versus host disease following bone marrow transplantation, cardiovascular diseases, autoimmune diseases, and liver diseases. Furthermore, genetic modification of MSCs to overexpress antitumor genes has provided prospects for clinical use as anticancer therapy. Here, we highlight the currently reported uses of MSCs in clinical trials and discuss their efficacy as well as their limitations.
Animals ; Cell Differentiation ; Cell Lineage ; Cell Movement ; Cell Proliferation ; Gene Expression Regulation ; Humans ; *Mesenchymal Stem Cell Transplantation/adverse effects ; Mesenchymal Stromal Cells/immunology/*physiology ; *Regeneration ; Regenerative Medicine/*methods ; Treatment Outcome