T-cell suppression mediated by mesenchymal stem cells is deficient in patients with severe aplastic anemia

Abstract Bone marrow mesenchymal stem cells (MSC) have potent immunosuppressive properties and are being evaluated in human trials of graft versus host disease (GVHD). The nature of their suppressive capacity is not well understood but attributed to their stem cell function. Evidence that adult stromal cells such as fibroblasts (Fb) also modulate T cell functions has important implications for immunoregulation and cellular therapy. We have investigated the phenomenon of MSC-mediated immunosuppression by comparing MSC with Fb of different origins in in vitro assays of T cell suppression and modulation. We have then isolated RNA from paired samples of dermal Fb and MSC from 6 healthy volunteers for comparative gene expression studies. Adherent Fb were isolated from digested dermis, synovium and lung. MSC were obtained from BM aspirate. Fb from the dermis, lung and synovium possess potent immunomodulatory properties. Fb suppress allogeneic T cell activation by autologously derived cutaneous antigen presenting cells and other stimulators. Fb-mediated suppression through soluble factors is dependent on IFNγ from activated T cells. IFNγ induces indoleamine-2, 3, dioxygenase in Fb with accelerated tryptophan metabolism being partly responsible for suppressing T cell proliferation. T cell suppression is reversible and exposure to stromal cells during activation reprogrammes T cells, increasing secretion of interleukin-4 2.3 fold, interleukin-10 4.3 fold and interleukin-13 15 fold (means of 4 experiments) upon restimulation. Increased Th2 polarization by stromal cells is associated with amelioration of pathological changes in an in vitro human GVHD model. Our findings also show that Fb from different sources are indistinguishable from MSC with respect to morphology, phenotype, growth and differentiation capacity in vitro. Clonogenicity (ratio of CFU to CD73+CD45- cells) of Fb and MSC are similar (range 0.2 to 0.46 CFU/cell) proving that the immunosuppressive effects of Fb from adult tissues are not due to the expansion of rare ‘stem’ cells. Using paired isolates of dermal Fb and MSC to control for inter-individual variation, we were able to define consistent differences in gene expression. Microarray assays were performed using a Human Genome Focus Affymetrix array and analysed with GeneSpring GX. 143 of 9600 probesets showed reproducible differences in transcript levels between dermal Fb and MSC. Probesets upregulated in MSC include genes encoding immunomodulatory mediators: vascular endothelial growth factor (7 fold), hydroxysteroid 17β dehydrogenase (10 fold) and jagged1 (5 fold); extracellular adhesion molecules: proteoglycan1 (264 fold), vascular cell adhesion molecule (175 fold), transglutaminase (67 fold) and procollagen (8 fold); and developmental regulators in the Hedgehog and Wnt signalling pathways. Our findings are further evidence that immunosuppression is a generic property of Fb isolated from several sources and not restricted to MSC. We have for the first time identified a differential expression profile of MSC compared with Fb. These differences may not confer unique in vivo immunosuppressive properties and the potential of Fb as an alternative source of cellular therapy remains untested.

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Combination of umbilical cord mesenchymal stem cells and standard immunosuppressive regimen for pediatric patients with severe aplastic anemia

BMC Pediatrics ◽

10.1186/s12887-021-02562-x ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Yang Lan ◽

Fang Liu ◽

Lixian Chang ◽

Lipeng Liu ◽

Yingchi Zhang ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Aplastic Anemia ◽

Umbilical Cord ◽

Pediatric Patients ◽

Statistical Significance ◽

Severe Aplastic Anemia ◽

Control Group ◽

Open Label ◽

Cell Counts

Abstract Background Defects of bone marrow mesenchymal stem cells (BM-MSCs) in proliferation and differentiation are involved in the pathophysiology of aplastic anemia (AA). Infusion of umbilical cord mesenchymal stem cells (UC-MSCs) may improve the efficacy of immunosuppressive therapy (IST) in childhood severe aplastic anemia (SAA). Methods We conducted an investigator-initiated, open-label, and prospective phase IV trial to evaluate the safety and efficacy of combination of allogenic UC-MSCs and standard IST for pediatric patients with newly diagnosed SAA. In mesenchymal stem cells (MSC) group, UC-MSCs were injected intravenously at a dose of 1 × 106/kg per week starting on the 14th day after administration of rabbit antithymocyte globulin (ATG), for a total of 3 weeks. The clinical outcomes and adverse events of patients with UC-MSCs infusion were assessed when compared with a concurrent control group in which patients received standard IST alone. Results Nine patients with a median age of 4 years were enrolled as the group with MSC, while the data of another 9 childhood SAA were analysed as the controls. Four (44%) patients in MSC group developed anaphylactic reactions which were associated with rabbit ATG. When compared with the controls, neither the improvement of blood cell counts, nor the change of T-lymphocytes after IST reached statistical significance in MSC group (both p > 0.05) and there were one (11%) patient in MSC group and two (22%) patients in the controls achieved partial response (PR) at 90 days after IST. After a median follow-up of 48 months, there was no clone evolution occurring in both groups. The 4-year estimated overall survival (OS) rate in two groups were both 88.9% ± 10.5%, while the 4-year estimated failure-free survival (FFS) rate in MSC group was lower than that in the controls (38.1% ± 17.2% vs. 66.7% ± 15.7%, p = 0.153). Conclusions Concomitant use of IST and UC-MSCs in SAA children is safe but may not necessarily improve the early response rate and long-term outcomes. This clinical trial was registered at ClinicalTrials.gov, identifier: NCT02218437 (registered October 2013).

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Poor Potential of Proliferation and Differentiation in Bone Marrow Mesenchymal Stem Cells Derived From Children with Severe Aplastic Anemia.

Blood ◽

10.1182/blood.v114.22.5081.5081 ◽

2009 ◽

Vol 114 (22) ◽

pp. 5081-5081

Author(s):

Ching-Tien Peng

Keyword(s):

Stem Cells ◽

Bone Marrow ◽

Mesenchymal Stem Cells ◽

Aplastic Anemia ◽

Severe Aplastic Anemia ◽

Population Doubling ◽

Bone Marrow Mscs ◽

Proliferative Capacity ◽

Differentiation Potential ◽

Proliferation And Differentiation

Abstract 5081 Introduction Idiopathic severe aplastic anemia (SAA), characterized by failure of hematopoiesis, is rare and potentially life-threatening to children. However, the pathogenesis has not been completely understood, and insufficiency in the hematopoietic microenvironment can be an important factor. Mesenchymal stem cells (MSCs) play an important role in maintaining bone marrow microenvironment. Therefore, we aimed at the intrinsic defects of bone marrow MSCs derived from SAA children. Materials and Methods Bone marrow MSCs were obtained from 5 SAA children and 5 controls. The morphology, immunophenotyping, proliferative capacity and differentiation potential of MSCs from SAA children were determined and compared with those of MSCs from controls. Results In vitro, MSCs of SAA and control group shared a similar spindle-shaped morphology. Both revealed a consistent immunophenotypic profile which was negative for CD45, CD14 and CD34, and positive for CD105, CD73, and CD44. However, SAA MSCs had slower expansion rate and smaller cumulative population doubling from passage 4 to 6 (1.83± 1.21 vs 3.36± 0.87; p = 0.046), indicating lower proliferative capacity. Besides, only 3 of 5 cultures of SAA group retained the ability to continue expansion till 80%-90% confluent cell layer beyond passage 6, suggesting earlier senescence of SAA MSCs. After osteogenic induction, SAA MSCs showed lower alkaline phosphatase activity (1.46± 0.04 vs 2.27± 0.32; p = 0.013), less intense von Kossa staining and lower gene expression of core binding factora1 (0.0015± 0.0005 vs 0.0056± 0.0017; p = 0.013). Following adipogenic induction, SAA MSCs showed less intense Oil red O staining (0.86± 0.22 vs 1.73± 0.42; p = 0.013) and lower lipoproteinlipase expression (0.0105± 0.0074 vs 0.0527± 0.0254; p = 0.013).The results of real time-PCR analysis for the assessment of lineage-specific genes were consistent with the findings of histochemical stains, and both indicated that SAA MSCs had poor osteogenic and adipogenic potential. Conclusions In this study, we demonstrated that bone marrow MSCs from children with SAA had poor potential of proliferation and differentiation. These alterations in MSCs may contribute to the failure of hematopoiesis, and lead to the development of the disease. Further studies are needed to elucidate the relationship between MSCs and SAA. Disclosures No relevant conflicts of interest to declare.

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Clinical Observation for the Treatment of Umibilical Cord Mesenchymal Stem Cells(UCMSC) on Severe Aplastic Anemia(SAA)

Blood ◽

10.1182/blood.v128.22.5054.5054 ◽

2016 ◽

Vol 128 (22) ◽

pp. 5054-5054 ◽

Cited By ~ 1

Author(s):

Qingchi Liu ◽

Zhuanzhen Zheng

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Aplastic Anemia ◽

Conventional Therapy ◽

Culture System ◽

Adverse Reactions ◽

Effective Rate ◽

Severe Aplastic Anemia ◽

Significant Progress ◽

Serum Free

Abstract Objective To investigate the safety and the efficacy of Umibilical cord mesenchymal stem cells(UCMSC) on severe aplastic anemia(SAA). Methods 30 cases who diagnosed SAA in our department from October 2013to January 2016 and treated with UCMSC on the basis of conventional treatment,were enrolled in this study prospectively.The cultured UCMSC using Serum-free culture system in vitro were given to patients with AA, interval of 15 days, 3 times for a course.the conventional treatments include CsA,male hormone and Chinese herb.Observed the changes of Th / Ts before and after treatmen ,Clinical efficacy and UCMSC infusion adverse reactions. Compared the efficacy of UCMSC therapy with conventional therapy of 30 cases of SAA at the same time. Results:Among 30 cases using umbilical cord mesenchymal stem cell infusion with UCMSC each infusion volume 3.2 × 106 / kg ~ 4.2 × 106 / kg, the average of 2.9 × 106 / kg, the average influsinon three times , 8 cases acquired basic cure, 8 cases acquired remission , 6 cases acquired significant progress in 6 cases, 8 cases were ineffective,with an effective rate of 73.3%.Before UCMSC treatment Th / Ts 0.67 ± 0.41, after1.33 ± 0.45, there was significant difference (P <0.05). There were 4 patients experienced transient fever during the influsion ,disappeared after symptomatic treatment, no other serious adverse reactions.Among 30 cases of SAA recived conventional therapy at the same period , 3cases acquired basic cure, 5cases acquired remission ,8cases acquired significant progress in 6 cases, 14 cases were ineffective,with an effective rate of 53.3%.The difference was significant (P <0.05). Conclusions:In vitro serum-free culture system can be used to culture and expand clinical scale UCMSC.UCMSC infusion can improve the SAA patient's Th / Ts proportion of T lymphocyte subpopulation , can improve the efficacy of new SAA, also more secure, no serious adverse reactions. Disclosures No relevant conflicts of interest to declare.

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