Effect of Cytokines Secreted by Human Adipose Stromal Cells on Endothelial Cells

Summary： To isolate and culture adipose stromal cells （ASCs）, and study the effect of cytokines secreted by ASCs on endothelial cells, human adipose tissue was digested with collagenase type Ⅰ solution and ASCs were derived by culture. The cells surface phenotype was examined by flow cytometry. ELISA was used to detect the secretion of VEGF, HGF, SDF- 1α and RT-PCR was employed to detect the expression of their mRNA. Then the ASC medium was utilized to culture human umbilical vein endothelial cells ECV304. Cells were counted by hemacytometer to determine the proliferation and Annexin V/ PI was employed for the examination of the apoptosis rate of ECV304. ASCs were derived by culture and expressed CD34, CD105 while they did not express CD31 or CD45. ASCs secreted cytokines such as VEGF, HGF and SDF-1α so the ASC medium could stimulate proliferation and counteract apoptosis of endothelial cells （P〈0.05）. Bcl-2 mRNA was also found to be up-regulated in the endothelial cells. It is concluded that ASCs can secrete cytokines and has significant effect on the proliferation of endothelial cells and apoptosis.

Editor's Choice—Differentiation of adipose stromal cells into neuron-like cells

Adult adipose stromal cells are accessible, numerous, show multipotent differentiation potential and low immunogenicity, and are not subjected to ethical issues. Additionally, they can be induced to differentiate into neuron-like cells and astrocytes in vitro through addition of β-mercaptoethanol and 0,5% anhydrous ethanol.

Comparative effectiveness of adipose-derived mesenchymal stromal cells in the management of knee osteoarthritis:A meta-analysis

BACKGROUND Osteoarthritis(OA)is the most common joint disorder,is associated with an increasing socioeconomic impact owing to the ageing population.AIM To analyze and compare the efficacy and safety of bone-marrow-derived mesenchymal stromal cells(BM-MSCs)and adipose tissue-derived MSCs(AD-MSCs)in knee OA management from published randomized controlled trials(RCTs).METHODS Independent and duplicate electronic database searches were performed,including PubMed,EMBASE,Web of Science,and Cochrane Library,until August 2021 for RCTs that analyzed the efficacy and safety of AD-MSCs and BM-MSCs in the management of knee OA.The visual analog scale(VAS)score for pain,Western Ontario McMaster Universities Osteoarthritis Index(WOMAC),Lysholm score,Tegner score,magnetic resonance observation of cartilage repair tissue score,knee osteoarthritis outcome score(KOOS),and adverse events were analyzed.Analysis was performed on the R-platform using OpenMeta(Analyst)software.Twenty-one studies,involving 936 patients,were included.Only one study compared the two MSC sources without patient randomization;hence,the results of all included studies from both sources were pooled,and a comparative critical analysis was performed.RESULTS At six months,both AD-MSCs and BM-MSCs showed significant VAS improvement(P=0.015,P=0.012);this was inconsistent at 1 year for BM-MSCs(P<0.001,P=0.539),and AD-MSCs outperformed BM-MSCs compared to controls in measures such as WOMAC(P<0.001,P=0.541),Lysholm scores(P=0.006;P=0.933),and KOOS(P=0.002;P=0.012).BM-MSC-related procedures caused significant adverse events(P=0.003)compared to AD-MSCs(P=0.673).CONCLUSION Adipose tissue is superior to bone marrow because of its safety and consistent efficacy in improving pain and functional outcomes.Future trials are urgently warranted to validate our findings and reach a consensus on the ideal source of MSCs for managing knee OA.

Adipose stromal/stem cells in regenerative medicine:Potentials and limitations

This article presents the stem and progenitor cells from subcutaneous adipose tissue,briefly comparing them with their bone marrow counterparts,and discussing their potential for use in regenerative medicine.Subcutaneous adipose tissue differs from other mesenchymal stromal/stem cells(MSCs)sources in that it contains a pre-adipocyte population that dwells in the adventitia of robust blood vessels.Pre-adipocytes are present both in the stromal-vascular fraction(SVF;freshly isolated cells)and in the adherent fraction of adipose stromal/stem cells(ASCs;in vitro expanded cells),and have an active role on the chronic inflammation environment established in obesity,likely due their monocyticmacrophage lineage identity.The SVF and ASCs have been explored in cell therapy protocols with relative success,given their paracrine and immunomodulatory effects.Importantly,the widely explored multipotentiality of ASCs has direct application in bone,cartilage and adipose tissue engineering.The aim of this editorial is to reinforce the peculiarities of the stem and progenitor cells from subcutaneous adipose tissue,revealing the spheroids as a recently described biotechnological tool for cell therapy and tissue engineering.Innovative cell culture techniques,in particular 3D scaffold-free cultures such as spheroids,are now available to increase the potential for regeneration and differentiation of mesenchymal lineages.Spheroids are being explored not only as a model for cell differentiation,but also as powerful 3D cell culture tools to maintain the stemness and expand the regenerative and differentiation capacities of mesenchymal cell lineages.

Cartilage and bone tissue engineering using adipose stromal/stem cells spheroids as building blocks

Scaffold-free techniques in the developmental tissue engineering area are designed to mimic in vivo embryonic processes with the aim of biofabricating,in vitro,tissues with more authentic properties.Cell clusters called spheroids are the basis for scaffold-free tissue engineering.In this review,we explore the use of spheroids from adult mesenchymal stem/stromal cells as a model in the developmental engineering area in order to mimic the developmental stages of cartilage and bone tissues.Spheroids from adult mesenchymal stromal/stem cells lineages recapitulate crucial events in bone and cartilage formation during embryogenesis,and are capable of spontaneously fusing to other spheroids,making them ideal building blocks for bone and cartilage tissue engineering.Here,we discuss data from ours and other labs on the use of adipose stromal/stem cell spheroids in chondrogenesis and osteogenesis in vitro.Overall,recent studies support the notion that spheroids are ideal"building blocks"for tissue engineering by“bottom-up”approaches,which are based on tissue assembly by advanced techniques such as three-dimensional bioprinting.Further studies on the cellular and molecular mechanisms that orchestrate spheroid fusion are now crucial to support continued development of bottom-up tissue engineering approaches such as three-dimensional bioprinting.

Experimental study of the effect of adipose stromal vascular fraction cells on the survival rate of fat transplantation

Objective To investigate the effect of adipose stromal vascular fraction cells(SVFs)on the survival rate of fat ransplantation.Methods 0.5mL autologous fat tissue was mixed with: ① DiI-labeled autologous SVFs (Group A);②

Is 1, 25-dihydroxyvitamin D_3 an ideal substitute for dexamethasone for inducing osteogenic differentiation of human adipose tissue-derived stromal cells in vitro?

Background Human adipose tissue-derived stromal cells （hADSCs） can be induced to differentiate along an osteoblastic lineage under stimulation of dexamethasone （DEX）. Recent studies, however, have questioned the efficacy of glucocorticoids such as DEX in mediating the osteogenesis process of skeletal progenitor cells and processed lipoaspirate cells. Is it possible to find a substitute for DEX？ Therefore, this study was designed to investigate osteogenic capacity and regulating mechanisms for osteoblastic differentiation of hADSCs by comparing osteogenic media （OM） containing either 1, 25-dihydroxyvitamin D3 （VD） or DEX and determine if VD was an ideal substitute for DEX as an induction agent for the osteogenesis of hADSCs. Methods Osteogenic differentiation of hADSCs was induced by osteogenic medium （OM） containing either 10 nmol/L VD or 100 nmol/L DEX. Differentiation of hADSCs into osteoblastic lineage was identified by alkaline phosphatase （ALP） staining, von Kossa staining, and reverse transcription-polymerase chain reaction assays for mRNA expression of osteogenesis-related genes such as type Ⅰ collagen （COL Ⅰ）, bone sialoprotein （BSP）, osteocalcin （OC）, bone morphogenetic protein （BMP）-2, BMP-4, BMP-6, BMP-7, runt-related transcription factor 2/core binding factor α1 （Runx2/Cbfal）, osterix （Osx）, and LIM mineralization protein- 1 （LMP- 1）. Results von Kossa staining revealed that the differentiated cells induced by both VD and DEX were mineralized in vitro. They also expressed osteoblast-related markers, such as ALP, COL Ⅰ, BSP, and OC. Runx2/Cbfal, Osx, BMP-6, and LMP-1 were upregulated during VD and DEX-induced hADSC osteoblastic differentiation, but BMP-4, BMP-7 were not. BMP-2 was only expressed in VD-induced differentiated cells. Conclusions VD or DEX-induced hADSCs differentiate toward the osteoblastic lineage in vitro. Runx2/Cbfal, Osx, BMP-2, BMP-6, and LMP-1 are involved in regulating osteoblastic differentiation of hADSCs, but BMP-4, BMP-7 are not. VD, but not DEX, induces expression of BMP-2 during osteogenic induction of hADSCs. VD is an ideal substitute for DEX for osteogenic induction of hADSCs.

Compatibility of Chitosan-Gelatin Films with Adipose Tissue Derived Stromal Cells

Chitosan has been shown to be a promising material for various applications in tissue engineering. Recently, adipose tissue derived stromal cells （ADSCs） have been investigated as an alternative source of seed cells for tissue engineering. The compatibility of chitosan and chitosan-gelatin complexes with ADSCs is not known. In the present study, ADSCs were isolated and characterized by phenotype using fluorescence-activated cell sorting （FACS）. The morphology, viability, and the ability of the ADSCs to differentiate on chitosan and chitosan-gelatin composite films with 60 wt.% gelatin were evaluated. Results show that the ADSCs are positive for CD29, CD44, and CD105, but negative for CD31, CD34, and CD45. ADSCs adhere and grow better on the composite films than on the chitosan films. The ability of ADSCs to differentiate into osteogenic and adipogenic lineage cells is not affected by their being cultured on chitosan-gelatin composite films. Therefore, chitosan-gelatin composite films are compatible with ADSCs and do not impair the ability of ADSCs to differentiate into osteogenic and adipogenic lineage cells.