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Goulas P, Karakwta M, Zatagias A, Bakoutsi M, Zevgaridis A, Ioannidis A, Krokou D, Michalopoulos A, Zevgaridis V, Koliakos G. A Simple and Effective Mechanical Method for Adipose-Derived Stromal Vascular Fraction Isolation. Cureus 2024; 16:e57137. [PMID: 38681268 PMCID: PMC11055620 DOI: 10.7759/cureus.57137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/27/2024] [Indexed: 05/01/2024] Open
Abstract
Over the last decades, there has been ongoing and evolving research concerning regenerative medicine, specifically, stem cells. The most common source of adult mesenchymal stem cells (MSCs) remains the adipose tissue and the easiest way to obtain such tissue is lipoaspirate. The fatty tissue obtained can be processed either in an enzymatic way, which is time-consuming and expensive and carries several dangers for the viability of the stem cells included, or with mechanical means which are fast, inexpensive, yield enough viable cells, and can be readily used for autologous transplantation in one-stage procedures. Herein, we demonstrate our non-enzymatic method for obtaining adipose-derived stromal vascular fraction comprising MSCs. The stromal vascular fraction was isolated via centrifugation, and the characteristics and numbers of the cells isolated have been tested with flow cytometry assay, cell culture, and differentiation. Over 91% of viable MSCs were isolated using the mechanical method. The cells retained the ability to differentiate into osteocytes, adipocytes, and chondrocytes. The method presented is simple, requiring no special equipment, and yields a viable population of stem cells in large numbers. These cells can be readily used in several operations (orthopedic, dentistry, fistulas, etc.) making feasible "one-stage" procedures, thus proving their benefits for the patient and the health care system.
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Affiliation(s)
- Patroklos Goulas
- 1st Propedeutic Surgical Department, American Hellenic Educational Progressive Association (AHEPA) University Hospital, Aristotle University of Thessaloniki, Thessaloniki, GRC
| | - Maria Karakwta
- Laboratory of Biological Chemistry, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, GRC
| | - Apostolos Zatagias
- 1st Propedeutic Surgical Department, American Hellenic Educational Progressive Association (AHEPA) University Hospital, Aristotle University of Thessaloniki, Thessaloniki, GRC
| | - Maria Bakoutsi
- Laboratory of Biological Chemistry, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, GRC
| | | | - Aristeidis Ioannidis
- Department of Surgery, American Hellenic Educational Progressive Association (AHEPA) University Hospital, Thessaloniki, GRC
| | - Despoina Krokou
- 1st Propedeutic Surgical Department, American Hellenic Educational Progressive Association (AHEPA) University Hospital, Aristotle University of Thessaloniki, Thessaloniki, GRC
| | - Antonios Michalopoulos
- 1st Propedeutic Surgical Department, American Hellenic Educational Progressive Association (AHEPA) University Hospital, Aristotle University of Thessaloniki, Thessaloniki, GRC
| | - Vasileios Zevgaridis
- 1st Surgical Department, Aristotle University of Thessaloniki, Thessaloniki, GRC
| | - George Koliakos
- Laboratory of Biological Chemistry, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, GRC
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Mesenchymal Stem Cells Combined with Tissue Fusion Technology Promoted Wound Healing in Porcine Bowel Anastomosis. Stem Cells Int 2020; 2020:5142797. [PMID: 32104185 PMCID: PMC7038387 DOI: 10.1155/2020/5142797] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 11/21/2019] [Accepted: 12/10/2019] [Indexed: 12/13/2022] Open
Abstract
Objective To evaluate the possible biological effect of allogenic mesenchymal stem cells (MSCs) combined with tissue fusion technology on the anastomosis. Methods Sixteen pigs were divided into a 7 d group and 14 d group, each of which was further subdivided into an MSC-treated group and a control group. Five anastomoses per animal were established using LigaSure ForceTriad (Covidien, MA, USA), a tissue sealing system. Cell migration and tissue-specific differentiation potency, in addition to potential cytokine and genetic changes, were investigated. Results There were no significant between-group differences in postoperative complications and anastomosis burst pressure. The number of proliferating cell nuclear antigen- (PCNA-) positive cells was significantly higher in the MSC-treated group as compared with that in the control group (P = 0.021). Labeled MSCs were found in the mucosal layer, villus, and lamina propria, as well as in the lamina muscularis mucosae, where they exhibited characteristics of smooth muscle cells. Conclusions Grafted MSCs significantly promoted epithelial and connective cell proliferation and maintained their cell migration capacity and differentiation potential in the fused anastomotic tissues, without causing severe postoperative complications.
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Angiogenesis in a 3D model containing adipose tissue stem cells and endothelial cells is mediated by canonical Wnt signaling. Bone Res 2017; 5:17048. [PMID: 29263938 PMCID: PMC5727463 DOI: 10.1038/boneres.2017.48] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 03/25/2017] [Accepted: 04/10/2017] [Indexed: 02/05/2023] Open
Abstract
Adipose-derived stromal cells (ASCs) have gained great attention in regenerative medicine. Progress in our understanding of adult neovascularization further suggests the potential of ASCs in promoting vascular regeneration, although the specific cues that stimulate their angiogenic behavior remain controversial. In this study, we established a three-dimensional (3D) angiogenesis model by co-culturing ASCs and endothelial cells (ECs) in collagen gel and found that ASC-EC-instructed angiogenesis was regulated by the canonical Wnt pathway. Furthermore, the angiogenesis that occurred in implants collected after injections of our collagen gel-based 3D angiogenesis model into nude mice was confirmed to be functional and also regulated by the canonical Wnt pathway. Wnt regulation of angiogenesis involving changes in vessel length, vessel density, vessel sprout, and connection numbers occurred in our system. Wnt signaling was then shown to regulate ASC-mediated paracrine signaling during angiogenesis through the nuclear translocation of β-catenin after its cytoplasmic accumulation in both ASCs and ECs. This translocation enhanced the expression of nuclear co-factor Lef-1 and cyclin D1 and activated the angiogenic transcription of vascular endothelial growth factor A (VEGFA), basic fibroblast growth factor (bFGF), and insulin-like growth factor 1 (IGF-1). The angiogenesis process in the 3D collagen model appeared to follow canonical Wnt signaling, and this model can help us understand the importance of the canonical Wnt pathway in the use of ASCs in vascular regeneration.
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You D, Nilsson E, Tenen DE, Lyubetskaya A, Lo JC, Jiang R, Deng J, Dawes BA, Vaag A, Ling C, Rosen ED, Kang S. Dnmt3a is an epigenetic mediator of adipose insulin resistance. eLife 2017; 6:30766. [PMID: 29091029 PMCID: PMC5730374 DOI: 10.7554/elife.30766] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 10/29/2017] [Indexed: 12/21/2022] Open
Abstract
Insulin resistance results from an intricate interaction between genetic make-up and environment, and thus may be orchestrated by epigenetic mechanisms like DNA methylation. Here, we demonstrate that DNA methyltransferase 3a (Dnmt3a) is both necessary and sufficient to mediate insulin resistance in cultured mouse and human adipocytes. Furthermore, adipose-specific Dnmt3a knock-out mice are protected from diet-induced insulin resistance and glucose intolerance without accompanying changes in adiposity. Unbiased gene profiling studies revealed Fgf21 as a key negatively regulated Dnmt3a target gene in adipocytes with concordant changes in DNA methylation at the Fgf21 promoter region. Consistent with this, Fgf21 can rescue Dnmt3a-mediated insulin resistance, and DNA methylation at the FGF21 locus was elevated in human subjects with diabetes and correlated negatively with expression of FGF21 in human adipose tissue. Taken together, our data demonstrate that adipose Dnmt3a is a novel epigenetic mediator of insulin resistance in vitro and in vivo.
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Affiliation(s)
- Dongjoo You
- Nutritional Sciences and Toxicology Department, University of California, Berkeley, Berkeley, United States
| | - Emma Nilsson
- Epigenetics and Diabetes Unit, Department of Clinical Sciences, Lund University Diabetes Centre, Scania University Hospital, Malmö, Sweden
| | - Danielle E Tenen
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Boston, United States
| | | | - James C Lo
- Weill Cornell Medical College, New York, United States
| | - Rencong Jiang
- Nutritional Sciences and Toxicology Department, University of California, Berkeley, Berkeley, United States
| | - Jasmine Deng
- Nutritional Sciences and Toxicology Department, University of California, Berkeley, Berkeley, United States
| | - Brian A Dawes
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Boston, United States
| | - Allan Vaag
- Diabetes and Metabolism, Department of Endocrinology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.,Early Clinical Development, AstraZeneca, Innovative Medicines, Göteborg, Sweden
| | - Charlotte Ling
- Epigenetics and Diabetes Unit, Department of Clinical Sciences, Lund University Diabetes Centre, Scania University Hospital, Malmö, Sweden
| | - Evan D Rosen
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Boston, United States.,Broad Institute of Harvard and MIT, Cambridge, United States
| | - Sona Kang
- Nutritional Sciences and Toxicology Department, University of California, Berkeley, Berkeley, United States
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Bateman ME, Strong AL, Hunter RS, Bratton MR, Komati R, Sridhar J, Riley KE, Wang G, Hayes DJ, Boue SM, Burow ME, Bunnell BA. Osteoinductive effects of glyceollins on adult mesenchymal stromal/stem cells from adipose tissue and bone marrow. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2017; 27:39-51. [PMID: 28314478 DOI: 10.1016/j.phymed.2017.02.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 01/04/2017] [Accepted: 02/12/2017] [Indexed: 06/06/2023]
Abstract
BACKGROUND While current therapies for osteoporosis focus on reducing bone resorption, the development of therapies to regenerate bone may also be beneficial. Promising anabolic therapy candidates include phytoestrogens, such as daidzein, which effectively induce osteogenesis of adipose-derived stromal cells (ASCs) and bone marrow stromal cells (BMSCs). PURPOSE To investigate the effects of glyceollins, structural derivatives of daidzein, on osteogenesis of ASCs and BMSCs. STUDY DESIGN Herein, the osteoinductive effects of glyceollin I and glyceollin II were assessed and compared to estradiol in ASCs and BMSCs. The mechanism by which glyceollin II induces osteogenesis was further examined. METHODS The ability of glyceollins to promote osteogenesis of ASCs and BMSCs was evaluated in adherent and scaffold cultures. Relative deposition of calcium was analyzed using Alizarin Red staining, Bichinchoninic acid Protein Assay, and Alamar Blue Assay. To further explore the mechanism by which glyceollin II exerts its osteoinductive effects, docking studies of glyceollin II, RNA isolation, cDNA synthesis, and quantitative RT-PCR (qPCR) were performed. RESULTS In adherent cultures, ASCs and BMSCs treated with estradiol, glyceollin I, or glyceollin II demonstrated increased calcium deposition relative to vehicle-treated cells. During evaluation on PLGA scaffolds seeded with ASCs and BMSCs, glyceollin II was the most efficacious in inducing ASC and BMSC osteogenesis compared to estradiol and glyceollin I. Dose-response analysis in ASCs and BMSCs revealed that glyceollin II has the highest potency at 10nM in adherent cultures and 1µM in tissue scaffold cultures. At all doses, osteoinductive effects were attenuated by fulvestrant, suggesting that glyceollin II acts at least in part through estrogen receptor-mediated pathways to induce osteogenesis. Analysis of gene expression demonstrated that, similar to estradiol, glyceollin II induces upregulation of genes involved in osteogenic differentiation. CONCLUSION The ability of glyceollin II to induce osteogenic differentiation in ASCs and BMSCs indicates that glyceollins hold the potential for the development of pharmacological interventions to improve clinical outcomes of patients with osteoporosis.
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Affiliation(s)
- Marjorie E Bateman
- Center for Stem Cell Research and Regenerative Medicine, Tulane University School of Medicine, New Orleans, LA, USA
| | - Amy L Strong
- Center for Stem Cell Research and Regenerative Medicine, Tulane University School of Medicine, New Orleans, LA, USA
| | - Ryan S Hunter
- Center for Stem Cell Research and Regenerative Medicine, Tulane University School of Medicine, New Orleans, LA, USA
| | - Melyssa R Bratton
- Cell and Molecular Biology Core Facility, Xavier University of Louisiana, New Orleans, LA, USA
| | - Rajesh Komati
- Department of Chemistry, Xavier University of Louisiana, New Orleans, LA, USA
| | - Jayalakshmi Sridhar
- Department of Chemistry, Xavier University of Louisiana, New Orleans, LA, USA
| | - Kevin E Riley
- Department of Chemistry, Xavier University of Louisiana, New Orleans, LA, USA
| | - Guangdi Wang
- Department of Chemistry, Xavier University of Louisiana, New Orleans, LA, USA
| | - Daniel J Hayes
- Department of Biological and Agricultural Engineering, Louisiana State University and Agricultural Center, Baton Rouge, LA, USA
| | - Stephen M Boue
- Southern Regional Research Center, US Department of Agriculture, 1100 Robert E. Lee Blvd, New Orleans, LA, USA
| | - Matthew E Burow
- Department of Medicine, Tulane University School of Medicine, New Orleans, LA, USA
| | - Bruce A Bunnell
- Center for Stem Cell Research and Regenerative Medicine, Tulane University School of Medicine, New Orleans, LA, USA; Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA; Division of Regenerative Medicine, Tulane National Primate Research Center, Tulane University, Covington, LA USA.
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Forghani A, Kriegh L, Hogan K, Chen C, Brewer G, Tighe TB, Devireddy R, Hayes D. Fabrication and characterization of cell sheets using methylcellulose and PNIPAAm thermoresponsive polymers: A comparison Study. J Biomed Mater Res A 2017; 105:1346-1354. [PMID: 28130868 DOI: 10.1002/jbm.a.36014] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2016] [Revised: 12/29/2016] [Accepted: 01/23/2017] [Indexed: 12/31/2022]
Abstract
Culturing cells on thermoresponsive polymers enables cells to be harvested as an intact cell sheet without disrupting the extracellular matrix or compromising cell-cell junctions. Previously, cell sheet fabrication methods using methylcellulose (MC) gel and PNIPAAm were independently demonstrated. In this study, MC and PNIPAAm fabrication methods are detailed and the resulting cell sheets characterized in parallel studies for direct comparison of human adipose derived stromal/stem cell (hASCs) sheet formation, cell morphology, viability, proliferation, and osteogenic potential over 21 days. A cell viability study revealed that hASCs in MC and PNIPAAm cell sheets remained viable for 21 days and proliferated until confluency. Osteogenic cell sheets exhibited upregulation of alkaline phosphatase (ALP) at day 7, as well as calcium deposition at 21 days. Additionally, expression of osteocalcin (OCN), a late-stage marker of osteogenesis, was quantified at days 14 and 21 using RT-PCR. OCN was upregulated in MC cell sheets at day 14 and PNIPAAm cell sheets at days 14 and 21. These results indicate that hASCs formed into cell sheets commit to an osteogenic lineage when cultured in osteogenic conditions. Cell sheets composed of hASCs may be used for further studies of hASC differentiation or surgical delivery of undifferentiated cells to defect sites. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1346-1354, 2017.
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Affiliation(s)
- Anoosha Forghani
- Department of Biomedical Engineering, Millennium Science Complex, Pennsylvania State University, University Park, Pennsylvania, 16802
| | - Lisa Kriegh
- Department of Biological and Agricultural Engineering, Louisiana State University & Agricultural, Center, E.B. Doran Building, Baton Rouge, Louisiana, 70803
| | - Katie Hogan
- Department of Biological and Agricultural Engineering, Louisiana State University & Agricultural, Center, E.B. Doran Building, Baton Rouge, Louisiana, 70803
| | - Cong Chen
- Department of Biomedical Engineering, Millennium Science Complex, Pennsylvania State University, University Park, Pennsylvania, 16802
| | - Gabrielle Brewer
- Department of Biological and Agricultural Engineering, Louisiana State University & Agricultural, Center, E.B. Doran Building, Baton Rouge, Louisiana, 70803
| | - Timothy B Tighe
- Materials Research Institute, Materials Characterization Lab, Millennium Science Complex, Pennsylvania State University, University Park, Pennsylvania, 16802
| | - Ram Devireddy
- Department of Mechanical Engineering, Louisiana State University, Patrick F. Taylor Hall, Baton Rouge, Louisiana, 70803
| | - Daniel Hayes
- Department of Biomedical Engineering, Millennium Science Complex, Pennsylvania State University, University Park, Pennsylvania, 16802
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Abstract
Adipose tissue has been shown to be particularly advantageous as source of mesenchymal stem cells (MSCs), because of its easy accessibility, and the possibility of obtaining stem cells in high yields. MSCs are obtained from the so-called Stromal Vascular Fraction, (SVF), exploiting their property of adhering to plastic surfaces and can be further purified by positive or negative immunomagnetic selection with appropriately chosen antibodies. These cells (Stromal Stem Cells, SSCs) can then be directly analyzed, frozen in liquid nitrogen, or expanded for further applications, e.g., for tissue engineering and regenerative medicine. The methodology described here in detail for SSCs isolated from mouse subcutaneous adipose tissue can be applied to human tissues, such as epicardium.
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Affiliation(s)
- Maria Prat
- Department of Health Sciences, Università del Piemonte Orientale "A.Avogadro", Via Solaroli, 17, 28100, Novara, Italy.
| | - Francesca Oltolina
- Department of Health Sciences, Università del Piemonte Orientale "A.Avogadro", Via Solaroli, 17, 28100, Novara, Italy
| | - Silvia Antonini
- Department of Health Sciences, Università del Piemonte Orientale "A.Avogadro", Via Solaroli, 17, 28100, Novara, Italy
| | - Andrea Zamperone
- Department of Health Sciences, Università del Piemonte Orientale "A.Avogadro", Via Solaroli, 17, 28100, Novara, Italy
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Marble HD, Sutermaster BA, Kanthilal M, Fonseca VC, Darling EM. Gene expression-based enrichment of live cells from adipose tissue produces subpopulations with improved osteogenic potential. Stem Cell Res Ther 2014; 5:145. [PMID: 25287061 PMCID: PMC4619280 DOI: 10.1186/scrt502] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 09/08/2014] [Indexed: 12/11/2022] Open
Abstract
Introduction Mesenchymal stem cells have been increasingly used for cell-based therapies. Adipose-derived stem/stromal cells (ASCs) from the stromal vascular fraction (SVF) of fat tissue are a particularly attractive option for cell based therapy given their accessibility and relative abundance. However, their application in both clinical and basic science investigations is complicated by the isolation of differentiable cells within the SVF. Current enrichment strategies, such as monolayer passaging and surface marker-based sorting, can be time-consuming or overly stringent. Ideally, a population of cells with great regenerative capacity could be isolated with high yields so that extensive in vitro manipulation is not necessary. The objective of this study was to determine whether SVF cells sorted based on expression of alkaline phosphatase liver/bone/kidney (ALPL) resulted in populations with increased osteogenic differentiation potential. Methods SVF samples were obtained from four, human donors and processed to isolate initial, heterogeneous cell populations. These SVF cells underwent a four day osteogenic priming period, after which they were treated with a fluorescent, oligodeoxynucleotide molecular beacon probe specific for ALPL mRNA. Cells were separated into positive and negative groups using fluorescence-activated cell sorting (FACS) then differentiated down the osteogenic lineage. Differentiation was assessed by measuring calcified matrix production in each sample. Results Cells positive for ALPL expression (ALPL+) represented approximately 34% of the gated population, while cells negative for ALPL expression (ALPL-) represented approximately 18%. ALPL+ cells produced 3.7-fold and 2.1-fold more calcified matrix than ALPL- and unsorted SVF cells, respectively, indicating a significant improvement in osteogenic differentiation. Further, ALPL+ cells showed increases in metabolite production for both adipogenesis and chondrogenesis, suggesting that the enrichment process yields an enhanced multipotent phenotype. Osteogenic differentiation response and cell yields for ALPL+ cells were markedly improved over surface marker-sorted samples. Conclusion This study demonstrates a novel method to enrich heterogeneous SVF cells for increased osteogenic potential. The procedure requires less time and results in higher yields of therapeutically useful cells than other existing approaches. Gene expression-based sorting of MSCs is a potentially paradigm-shifting approach that could benefit applications spanning from basic science to clinical therapy. Electronic supplementary material The online version of this article (doi:10.1186/scrt502) contains supplementary material, which is available to authorized users.
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Laschke MW, Schank TE, Scheuer C, Kleer S, Shadmanov T, Eglin D, Alini M, Menger MD. In vitro osteogenic differentiation of adipose-derived mesenchymal stem cell spheroids impairs their in vivo vascularization capacity inside implanted porous polyurethane scaffolds. Acta Biomater 2014; 10:4226-35. [PMID: 24998773 DOI: 10.1016/j.actbio.2014.06.035] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 06/06/2014] [Accepted: 06/24/2014] [Indexed: 12/22/2022]
Abstract
Undifferentiated adipose-derived mesenchymal stem cell (adMSC) spheroids are attractive vascularization units for tissue engineering. Their osteogenic differentiation further offers the possibility of directed generation of bone constructs. The aim of this study was to analyze how this differentiation affects their in vivo vascularization capacity. Green fluorescent protein (GFP)-positive adMSCs were isolated from C57BL/6-TgN(ACTB-EGFP)1Osb/J mice for the generation of undifferentiated and differentiated spheroids using the liquid overlay technique. Subsequently, polyurethane scaffolds were seeded with these spheroids and successful osteogenic differentiation was proven by von Kossa staining and high-resolution microtomography. The scaffolds were then implanted into dorsal skinfold chambers of C57BL/6 wild-type mice to analyze their vascularization and incorporation using intravital fluorescence microscopy, histology and immunohistochemistry. Scaffolds seeded with differentiated spheroids exhibited a markedly impaired vascularization. Immunohistochemical analyses revealed that this was caused by the lost ability of differentiated spheroids to form GFP-positive microvascular networks inside the scaffolds. This was associated with a reduced tissue incorporation of the implants. Moreover, they no longer exhibited a mineralized matrix after the 14day implantation period, indicating the dedifferentiation of the spheroids under the given in vivo conditions. These findings indicate that osteogenic differentiation of adMSC spheroids markedly impairs their vascularization capacity. Hence, it may be reasonable to combine adMSC spheroids of varying differentiation stages in scaffolds for bone tissue engineering to promote both vascularization and bone formation.
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