Project description:Improving the poor microenvironment in the joint cavity has potential for treating cartilage injury, and mesenchymal stem cell (MSC)-derived exosomes (MSC-Exos), which can modulate cellular behavior, are becoming a new cell-free therapy for cartilage repair. Here, we used acellular cartilage extracellular matrix (ACECM) to prepare 3D scaffolds and 2D substrates by low-temperature deposition modeling (LDM) and tape casting. We aimed to investigate whether MSC-Exos cultured on scaffolds of different dimensions could improve the poor joint cavity microenvironment caused by cartilage injury and to explore the related mechanisms. In vitro experiments showed that exosomes derived from MSCs cultured on three-dimensional (3D) scaffolds (3D-Exos) had increased efficiency. In short-term animal experiments, compared with exosomes derived from MSCs cultured in a two-dimensional (2D) environment (2D-Exos), 3D-Exos had a stronger ability to regulate the joint cavity microenvironment. Long-term animal studies confirmed the therapeutic efficacy of 3D-Exos over 2D-Exos. Thus, 3D-Exos were applied in the rat knee osteochondral defect model after adsorption in the micropores of the scaffold and combined with subsequent articular cavity injections, and they showed a stronger cartilage repair ability. These findings provide a new strategy for repairing articular cartilage damage. Furthermore, miRNA sequencing indicated that the function of 3D-Exos may be associated with high expression of miRNAs. Thus, our study provides valuable insights for the design of 3D-Exos to promote cartilage regeneration.
Project description:In the field of regenerative medicine, umbilical cord-derived mesenchymal stem cells (UC-MSCs) have a plausible potential. However, traditional two-dimensional (2D) culture systems remain limited in replicating the complex in vivo microenvironment. Thus, three-dimensional (3D) cultures offer a more physiologically relevant model. This study explored the impact of 3D culture conditions on the UC-MSC secretome and its ability to promote angiogenesis, both in vitro and in vivo. In this study, using two distinct methods, we successfully cultured UC-MSCs: in a monolayer (2D-UC-MSCs) and as spheroids formed in U-shaped 96-well plates (3D-UC-MSCs). The presence and expression of proangiogenic miRNAs in the conditioned media (CM) of these cultures were investigated, and differential expression patterns were explored. Particularly, the CM of 3D-UC-MSCs revealed significantly higher levels of miR-21-5p, miR-126-5p, and miR-130a-3p compared to 2D-UC-MSCs. Moreover, the CM from 3D-UC-MSCs revealed a higher effect on endothelial cell proliferation, migration, and tube formation than did the CM from 2D-UC-MSCs, indicating their proangiogenic potential. In an in vivo Matrigel plug mouse model, 3D-UC-MSCs (cells) stimulated greater vascular formation compared to 2D-UC-MSCs (cells). 3D culture of UC-MSCs' secretome improves the promotion of angiogenesis.
Project description:Stem cell-derived exosomes are emerging as novel and clinically relevant cell-free therapeutics for regenerative therapy. This work focused on investigating the stimulation of fibroblasts by exosomes derived from umbilical cord-derived mesenchymal stem cells (ucMSC) in a defined serum-free three-dimensional (3D) culture. 3D culture of ucMSC was carried out in medium supplemented with KnockOut serum replacement (KO-medium) using the Aggrewell system. ucMSC in KO-medium formed spheroids with maintained size and integrity throughout culture. This enabled the isolation of vesicles from ucMSC spheroids in KO-medium with sizes that fall within the exosomal size range and were positive for the expression of canonical exosomal markers CD63, CD9, CD81, Alix, and TSG101. The ucMSC-derived exosomes (ExoucMSC ) were shown to significantly increase the migration and proliferation of murine fibroblasts in vitro. To conclude, 3D culture of ucMSC in defined serum-free KO-medium formed viable spheroids which enabled the isolation of ExoucMSC with the potential of accelerating wound healing.
Project description:Colorectal cancer demonstrates intra-tumour heterogeneity formed by a hierarchical structure comprised of cancer stem cells (CSCs) and their differentiated progenies. The mechanism by which CSCs are maintained and differentiated needs to be further elucidated, and there is evidence that the tumour microenvironment governs cancer stemness. Using PLR123, a colon cancer cell line with CSC properties, we determined the culture conditions necessary to establish a pair of three-dimensional (3D) culture models grown in Matrigel, designated stemCO and diffCO. The conditions were determined by comparing the phenotypes in the models with PLR123 mouse xenografts colonising lung and liver. StemCO resembled LGR5-positive undifferentiated tumours in the lung, and diffCO had lumen structures composed of polarised cells that were similar to the ductal structures found in differentiated tumours in the liver. In a case using the models for biomedical research, treatment with JAG-1 peptide or a γ-secretase inhibitor modified the Notch signaling and induced changes indicating that the signal participates in lumen formation in the models. Our results demonstrate that culture conditions affect the stemness of 3D culture models generated from CSCs and show that comparing models with different phenotypes is useful for studying how the tumour environment regulates cancer.
Project description:BackgroundMesenchymal stem cells (MSCs) have shown a positive effect on Osteoarthritis (OA), but the efficacy is still not significant in clinical. Conventional two-dimensional (2D) monolayer culture method is prone to cause MSCs undergoing replication senescence, which may affect the functions of MSCs. Three-dimensional (3D) culture strategy can sustain cell proliferative capacity and multi-differentiation potential. This study aimed to investigate the therapeutic potential of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) cultured by 3D hanging drop method on OA.MethodshUC-MSCs were isolated from umbilical cord and cultured by 3D hanging drop method for 48 h. Scanning electron microscopy (SEM) was used to observe gross morphology 2D and 3D hUC-MSCs. Transcriptome comparison of gene expression differences between 2D and 3D hUC-MSCs. GO enrichment analysis, KEGG pathway enrichment analysis and GSEA enrichment analysis were used to analyze the impact of 3D hanging drop culture on the biological functions of hUC-MSCs. Female New Zealand rabbits (n = 12) were divided into 4 groups: Normal group, Model group, 2D hUC-MSCs treatment group and 3D hUC-MSCs treatment group. After 8 weeks, the gross and histological appearance of the cartilage was evaluated by safranin O-fast green staining and Mankin scoring system. The expression of type I collagen and type II collagen was detected by immunohistochemistry. The levels of IL-6, IL-7, TNFα, TGFβ1 and IL-10 in the knee joint fluid were tested by ELISA.Results3D hanging drop culture changed cell morphology but did not affect phenotype. The MSCs transcriptome profiles showed that 3D hanging drop culture method enhanced cell-cell contact, improved cell responsiveness to external stimuli and immunomodulatory function. The animal experiment results showed that hUC-MSCs could promote cartilage regeneration compared with Model group. 3D hUC-MSCs treatment group had a higher histological score and significantly increased type II collagen secretion. In addition, 3D hUC-MSCs treatment group increased the expression of anti-inflammatory factors TGFβ1 and IL-10.ConclusionThe above experimental results illustrated that 3D hanging drop culture method could enhance the therapeutic effect of hUC-MSCs, and showed a good clinical application prospect in the treatment of OA.
Project description:Human umbilical cord mesenchymal stem cells (hUCMSCs) are considered to be an ideal replacement for bone marrow MSCs. However, up to date, there is no convenient and efficient method for hUCMSC isolation and culture. The present study was carried out to explore the modified enzyme digestion for hUCMSC in vitro. Conventional enzyme digestion, modified enzyme digestion, and tissue explant were used on hUCMSCs to compare their efficiencies of isolation and culture, to observe primary cell growth and cell subculture. The results show that the cells cultured using the tissue explant method had a longer culture cycle (P < 0.01) and lower yield of primary cells per centimetre of umbilical cord (P < 0.01) compared with the two enzyme digestion methods. Subculture adherence and cell doubling took significantly less time with the tissue explant method (P < 0.05) than with the conventional enzyme digestion method; however, there was no significant difference between the tissue explant method and the modified enzyme digestion method (P > 0.05). Comparing two enzyme digestion methods, the modified method yielded more cells than did the conventional method (P < 0.01), and primary cell adherence took significantly less time with the modified method than with the conventional method (P < 0.05). Cell cycle analysis of the third-generation hUCMSCs cultured by modified enzyme digestion method indicated that most cells were quiescent. Immunofluorescence staining showed that these cells expressed MSC markers CD44 and CD90. And Von Kossa and oil red O staining detection showed that they could be differentiated into osteoblasts and adipocytes with induction medium in vitro. This study suggests that hUCMSC isolation and culture using 0.2 % collagenase II at 37 °C for digestion of 16-20 h is an effective and simple modified enzyme digestion method.
Project description:BackgroundSilicosis is an occupational respiratory disease caused by long-term excessive silica inhalation, which is most commonly encountered in industrial settings. Unfortunately, there is no effective therapy to delay and cure the progress of silicosis. In the recent years, stem cell therapy has emerged as an attractive tool against pulmonary fibrosis (PF) owing to its unique biological characteristics. However, the direct use of stem cells remains limitation by many risk factors for therapeutic purposes. The exclusive utility of exosomes secreted from stem cells, rather than cells, has been considered a promising alternative to overcome the limitations of cell-based therapy while maintaining its advantages.Methods and resultsIn this study, we first employed a three-dimensional (3D) dynamic system to culture human umbilical cord mesenchymal stem cell (hucMSC) spheroids in a microcarrier suspension to yield exosomes from serum-free media. Experimental silicosis was induced in C57BL/6J mice by intratracheal instillation of a silica suspension, with/without exosomes derived from hucMSC (hucMSC-Exos), injection via the tail vein afterwards. The results showed that the gene expression of collagen I (COL1A1) and fibronectin (FN) was upregulated in the silica group as compared to that in the control group; however, this change decreased with hucMSC-Exo treatment. The value of FEV0.1 decreased in the silica group as compared to that in the control group, and this change diminished with hucMSC-Exo treatment. These findings suggested that hucMSC-Exos could inhibit silica-induced PF and regulate pulmonary function. We also performed in vitro experiments to confirm these findings; the results revealed that hucMSC-Exos decreased collagen deposition in NIH-3T3 cells exposed to silica.ConclusionsTaken together, these studies support a potential role for hucMSC-Exos in ameliorating pulmonary fibrosis and provide new evidence for improving clinical treatment induced by silica.
Project description:Despite advances in ex vivo expansion of cord blood-derived hematopoietic stem/progenitor cells (CB-HSPC), challenges still remain regarding the ability to obtain, from a single unit, sufficient numbers of cells to treat an adolescent or adult patient. We and others have shown that CB-HSPC can be expanded ex vivo in two-dimensional (2D) cultures, but the absolute percentage of the more primitive stem cells decreases with time. During development, the fetal liver is the main site of HSPC expansion. Therefore, here we investigated, in vitro, the outcome of interactions of primitive HSPC with surrogate fetal liver environments. We compared bioengineered liver constructs made from a natural three-dimensional-liver-extracellular-matrix (3D-ECM) seeded with hepatoblasts, fetal liver-derived (LvSt), or bone marrow-derived stromal cells, to their respective 2D culture counterparts. We showed that the inclusion of cellular components within the 3D-ECM scaffolds was necessary for maintenance of HSPC viability in culture, and that irrespective of the microenvironment used, the 3D-ECM structures led to the maintenance of a more primitive subpopulation of HSPC, as determined by flow cytometry and colony forming assays. In addition, we showed that the timing and extent of expansion depends upon the biological component used, with LvSt providing the optimal balance between preservation of primitive CB HSPC and cellular differentiation. Stem Cells Translational Medicine 2018;7:271-282.
Project description:Considerable research has been dedicated to restoring myocardial cell slippage and limiting ventricular remodeling after myocardial infarction (MI). We examined the ability of a three-dimensional (3D) engineered fibrin patch filled with human umbilical cord blood-derived mesenchymal stem cells (UCBMSCs) to induce recovery of cardiac function after MI. The UCBMSCs were modified to coexpress luciferase and fluorescent protein reporters, mixed with fibrin, and applied as an adhesive, viable construct (fibrin-cell patch) over the infarcted myocardium in mice (MI-UCBMSC group). The patch adhered well to the heart. Noninvasive bioluminescence imaging demonstrated early proliferation and differentiation of UCBMSCs within the construct in the postinfarct mice in the MI-UCBMSC group. The implanted cells also participated in the formation of new, functional microvasculature that connected the fibrin-cell patch to both the subjacent myocardial tissue and the host circulatory system. As revealed by echocardiography, the left ventricular ejection fraction and fractional shortening at sacrifice were improved in MI-UCBMSC mice and were markedly reduced in mice treated with fibrin alone and untreated postinfarction controls. In conclusion, a 3D engineered fibrin patch composed of UCBMSCs attenuated infarct-derived cardiac dysfunction when transplanted locally over a myocardial wound.
Project description:It is unclear whether extracellular vesicles (EVs) from mesenchymal stem cells (MSCs) have a direct protective effect on pancreatic islets. In addition, whether culturing MSCs in three dimensions (3D) instead of a monolayer (2D) can induce changes in the cargo of EVs that facilitate the polarization of macrophages into an M2 phenotype has not been investigated. We sought to determine whether EVs from MSCs cultured in 3D can prevent inflammation and dedifferentiation in pancreatic islets and, if so, whether the protective effect is superior to that of EVs from 2D MSCs. Human umbilical cord blood- (hUCB-) MSCs cultured in 3D were optimized according to cell density, exposure to hypoxia, and cytokine treatment based on the ability of the hUCB-MSC-derived EVs to induce the M2 polarization of macrophages. Islets isolated from human islet amyloid polypeptide (hIAPP) heterozygote transgenic mice were cultured in serum-deprived conditions with hUCB-MSC-derived EVs. EVs derived from 3D hUCB-MSCs had more abundant microRNAs involved in M2 polarization of macrophages and had an enhanced M2 polarization ability on macrophages, which was optimized when the 3D culture condition was 2.5 × 104 cells per spheroid without preconditioning with hypoxia and cytokine exposure. When islets isolated from hIAPP heterozygote transgenic mice were cultured in serum-deprived conditions with hUCB-MSC-derived EVs, the EVs derived from 3D hUCB-MSCs suppressed the expression of proinflammatory cytokines and caspase-1 in pancreatic islets and increased the proportion of M2-polarized islet-resident macrophages. They improved glucose-stimulated insulin secretion, reduced the expression of Oct4 and NGN3, and induced the expression of Pdx1 and FoxO1. The greater suppression of IL-1β, NLRP3 inflammasome, caspase-1, and Oct4 and induction of Pdx1 and FoxO1 were found in islets cultured with the EVs derived from 3D hUCB-MSCs. In conclusion, EVs derived from 3D hUCB-MSCs optimized for M2 polarization attenuated nonspecific inflammation and preserved β-cell identity of pancreatic islets.