Adipose Stromal Vascular Fraction Cells Research Articles

Induction of dedifferentiated male mouse adipose stromal vascular fraction cells to primordial germ cell-like cells.

The adipose stromal vascular fraction (SVF) contains abundant mesenchymal stem cell populations that have a limited ability to self-renew and differentiate. Male mouse adipose SVF cells were dedifferentiated by reprogramming factors (c-Myc, Oct4, Sox2, and Klf4) to form embryonic stem cell-like cells (ESCLCs), which upgraded their limited differentiation potential. The ESCLCs were induced to differentiate toward epiblast-like cells (EpiLCs) and primordial germ cell-like cells (PGCLCs) by culturing in media supplied with activin A and BMP-4, respectively. The derived ESCLCs possess embryonic stem cell features and can automatically form embryonic bodies. After culture in EpiLC induction medium for 2-3 days, ESCLCs formed flattened epithelial structures that were different from their original water drop-like colonies, and the expression of pluripotency-related genes decreased. When the cells that had been cultured in EpiLC induction medium for 2 days were isolated and cultured in PGCLC induction medium for 4-6 days, they formed typical water drop-like colonies again. Moreover, expression of the pluripotency-related genes and the primordial germ cell (PGC) specification-related genes increased. During progression from ESCLCs toward EpiLCs and PGCLCs, the levels of histone methylases H3K9me2 and H3K27me3 kept changing, which resembled those seen in PGC specification. The derived PGCLCs expressed SSEA-1, Blimp-1, and Stella. Furthermore, methylation of Igf2r and Snrpn was retained, but H19 and Kcnq1ot1 methylation levels were slightly reduced compared to non-PGCLCs, suggesting that the derived PGCLCs may have initiated the process of imprint erasure.

Autologous Adipose-derived Stromal Stem Cell Implantation to Resolve Critical Limb Ischemia: Case Report

Critical limb ischemia (CLI) is a debilitating condition for which limited therapeutic options exist. Characterized by ischemia of the lower limb due to vascular deficiency, attempts have been made to stimulate angiogenesis utilizing cell and gene-based approaches. Adipose stromal vascular fraction (SVF) cells are a practical source of autologous tissue that can be prepared inexpensively in a same-day procedure. Recent studies have demonstrated SVF to be highly angiogenic, as well as clinically safe in a variety of contexts. Here, we describe the rationale and, to our knowledge, the first successful clinical implementation of autologous SVF cells for the treatment of a no-option CLI patient.

Encapsulation of Adipose Stromal Vascular Fraction Cells in Alginate Hydrogel Spheroids Using a Direct-Write Three-Dimensional Printing System

The study of tissue function in vitro has been aided by the development of three-dimensional culture systems that more accurately duplicate the complex cell components of tissues and organs. Bioprinting of cells provides a rapid tissue fabrication technique that can be used to evaluate normal and pathologic conditions in vitro as well as to construct complex three-dimensional tissue structures for implantation in regenerative medicine therapies. Studies were performed using a direct write three-dimensional bioprinting system to fabricate adipose-derived stromal vascular fraction cell spheroids. Human fat–derived stromal vascular fraction cells were mixed in 1.5% (w/v) alginate solutions, and fabrication conditions were varied to produce an array of spheroids. The spheroids were placed in spinner culture, and spheroid integrity and encapsulated cell viability were assessed for 16 days. Results establish the ability to tightly control adipose SVF spheroids in the range of 800–1500 μm. Fabrication conditions were used to control spheroid size, and the results illustrate the ability to construct spheroids of precise size and shape. The adipose SVF cell population remains viable and the spheroid integrity was maintained for 16 days in suspension culture. The direct-write printing of adipose stromal vascular fraction cell containing spheroids provides a rapid fabrication technology to support in vitro microphysiologic system studies.

Abstract 31: Vascular Repair by Adipose Stromal Fraction (SVF) cells in a Murine Model of Small Vessel Inflammation

The relatively few therapeutic options for treating small vessel disease creates a significant clinical challenge. The stromal vascular fraction (SVF) derived from adipose tissue is a rich source of regenerative cells shown to have anti-inflammatory and vascular reparative capabilities. We explored the ability of these SVF cells to reverse vascular insult in a murine model of artery inflammation induced by the placement of a 2 mm long polyethylene cuff around the left femoral artery in male wildtype FVB/n mice. One week after cuffing, freshly isolated SVF cells harvested from syngeneic FVB/n Tg(CAG-luc,-GFP) mice ubiquitously and constitutively expressing the firefly luciferase and green fluorescent protein genes were injected via a tail vein. Sham mice, which underwent femoral exposure without receiving a cuff, were treated identically. Bioluminescence confirmed delivery and the persistent presence of SVF cells. Histological analysis of vessels indicated cuffed femoral arteries were surrounded by granulation tissue and exhibited intimal lesions associated with significant medial inward remodeling. In contrast, intravenous delivery of SVF cells after lesion formation, regardless of the dose, lessened intimal lesions, reversed medial remodeling, and reduced perivascular fibrosis. Immunostaining for luciferase identified SVF cells throughout the vessel wall and the surrounding extra-vascular tissue that were also positive for markers of M1 and M2 macrophages. In conclusion, intravenous delivery of freshly isolated adipose SVF cells reversed the vascular insult and peri-vascular granulation tissue due to inflammation.

Adipose Stromal Vascular Fraction Cells Isolated Using an Automated Point of Care System Improve the Patency of Expanded Polytetrafluoroethylene Vascular Grafts

We evaluated the use of an automated, point-of-care instrument to derive canine adipose stromal vascular fraction cells, and the subsequent deposition of these cells onto the luminal surface of an expanded polytetrafluoroethylene (ePTFE) vascular graft for use as a bypass graft. The hypothesis evaluated was that an instrument requiring minimal user interface will provide a therapeutic dose of cells to improve the patency of synthetic vascular grafts in an autologous animal model of graft patency. The stromal vascular fraction (SVF) cells were isolated using an automated adipose tissue processing and cell isolation system and cells sodded onto the surface of an ePTFE vascular graft. Control grafts, used off-the-shelf without cell treatment were used as a control to assess patency effects. Each animal received a control, untreated graft implanted in one carotid artery, and the cell-treated graft implanted in the carotid artery on the contralateral side. The grafts were implanted for 6 months utilizing 12 animals. Results indicate a fully automated adipose tissue processing system will consistently produce functional autologous cells for immediate use in the operating room. Cell-sodded polymeric grafts exhibited improved patency compared to control grafts after 6 month implantation in the canine carotid artery model.

Human adipose stromal vascular cell delivery in a fibrin spray.

Adipose tissue represents a practical source of autologous mesenchymal stromal cells (MSCs) and vascular-endothelial progenitor cells, available for regenerative therapy without in vitro expansion. One of the problems confronting the therapeutic application of such cells is how to immobilize them at the wound site. We evaluated in vitro the growth and differentiation of human adipose stromal vascular fraction (SVF) cells after delivery through the use of a fibrin spray system. SVF cells were harvested from four human adult patients undergoing elective abdominoplasty, through the use of the LipiVage system. After collagenase digestion, mesenchymal and endothelial progenitor cells (pericytes, supra-adventitial stromal cells, endothelial progenitors) were quantified by flow cytometry before culture. SVF cells were applied to culture vessels by means of the Tisseel fibrin spray system. SVF cell growth and differentiation were documented by immunofluorescence staining and photomicrography. SVF cells remained viable after application and were expanded up to 3 weeks, when they reached confluence and adipogenic differentiation. Under angiogenic conditions, SVF cells formed endothelial (vWF+, CD31+ and CD34+) tubules surrounded by CD146+ and α-smooth muscle actin+ perivascular/stromal cells. Human adipose tissue is a rich source of autologous stem cells, which are readily available for regenerative applications such as wound healing, without in vitro expansion. Our results indicate that mesenchymal and endothelial progenitor cells, prepared in a closed system from unpassaged lipoaspirate samples, retain their growth and differentiation capacity when applied and immobilized on a substrate using a clinically approved fibrin sealant spray system.

Experimental study on the best concentration of SVFs for promoting survival rate of fat graft

To investigate the effect of different concentrations of human adipose stromal vascular fraction cells (SVFs) on the survival rate of fat transplantation. 0.3 ml fat tissue, derived and refined from clinical liposuction patients, was mixed with different concentrations of SVFs as 5 x 10(5)/ml in Group A, or 1 x 10(6)/ml in Group B, or 2 x 10(6)/ml in Group C, or completely medium in control group D. Then the mixture was injected randomly under the back skin of 6 nude mice. The transplanted fat tissue in four groups was harvested at 3 months after implantation. Wet weight of fat grafts was measured for macroscopic aspects. After HE staining, blood vessel density, viable adipocytes and fibrous proliferation were counted respectively for histological evaluation. The wet weight of fat grafts in group B (81.670 +/- 7.528) mg was significantly higher than that in group A, C, D [(60.000 +/- 6.325) mg, (68.330 +/- 7.528) mg, (48.330 +/- 7.528) mg, respectively, P < 0.05)], but the difference between group A and group C was not statistically significant (P > 0.05). The grafts in group A, B and C had significantly higher blood vessel density than those in the control group D, whereas blood vessel density was the highest in group B (P < 0.05) and there was no significant difference between group A and C (P > 0.05). Compared with group A, C and D, histological analysis revealed that the fat grafts in group B was consisted predominantly of adipose tissue with less fat necrosis and fibrosis (P < 0.05). However, fibrosis counts were significant lower in group A, B and C than those in group D (P < 0.05), and there was no significant difference between group A and C (P > 0.05). The human isolated SVFs has the advantages to improve the survival rate of fat transplantation, and the magnitude of 1 x 10(6)/ml is more practical and safe, indicating a wide clinical application in the future.

Experimental study of the effect of adipose stromal vascular fraction cells with VEGF on the neovascularization of free fat transplantation

To investigate the effect of adipose stromal vascular fraction cells (SVFs) with VEGF on the neovascularization of free fat transplantation. SVFs were obtained from subcutaneous fat and labelled with DiI. 0.3 ml autologous fat tissue was mixed with 0.2 ml cells: 1) autologous SVFs with VEGF (Group A); 2) autologous SVFs (Group B); 3) complete DMEM (Group C) And then the mixture was injected randomly under the back skin of 12 nude mice. The transplanted fat tissue in three groups was harvested at 2 months after implantation. Wet weight and diameter of fat grafts was measured. After HE and CD31 staining,blood vessel density, viable adipocytes and fibrous proliferation were observed. Trace of SVFs labeled by DiI in vivo could be detected by fluorescent microscope. The wet weight of fat grafts was (191.90 +/- 9.81) mg in group A, (177.01 +/- 10.50) mg in group B, and (92.05 +/- 8.30) mg in group C (P<0.01). The diameter of fat grafts was (0.49 +/- 0.24) cm in group A, (0.40 +/- 0.26) cm in group B, and (0.32 +/- 0.28) cm in group C (P<0.01). Histological analysis showed the blood vessel density was (14.58 +/- 2.06)/HPL in group A, (11.55 +/- 2.18)/HPL in group B, (7.87 +/- 1.55)/HPL in group C. Compared with group B and group C, group A had more adipose tissue with less fat necrosis and fibrosis and had significantly higher capillary density. The autologous adipose stromal vascular fraction cells with VEGF could improve the neovascularization of free fat significantly. It indicates a wide clinical application in the future.

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

To investigate the effect of adipose stromal vascular fraction cells (SVFs) on the survival rate of fat transplantation. 0. 5 ml autologous fat tissue was mixed with: 1) Di-labeled autologous SVFs ( Group A); 2) Di-labeled autologous adipose-derived stem cells (ASCs) (Group B); 3)Complete DMEM (Group C). And then the mixture was injected randomly under the back skin of 14 rabbits. The transplanted fat tissue in three groups was harvested at 6 months after implantation. Wet weight of fat grafts was measured for macroscopic aspects. After HE staining, blood vessel density, viable adipocytes and fibrous proliferation were counted respectively for histological evaluation. Trace of DiI-labeled ASCs in vivo was detected by fluorescent microscope. The wet weight of fat grafts in group A (291.0 +/- 72.1) mg and group B (269.3 +/- 67.3) mg was significantly higher than that in group C (177.8 +/- 60.0) mg, but the difference between Group A and Group B was not significant. Histological analysis revealed that the fat grafts in group A and B was consisted predominantly of adipose tissue with less fat necrosis and fibrosis, compared with the fat grafts in group C. The grafts in both group A and B had significantly higher capillary density than those in the control group. Part of vascular endothelial cells were observed to origin from ectogenic DiI-labeled SVFs and ASCs. The autologous isolated SVFs has a similar effect as autologous cultured ASCs to improve the survival rate of fat transplantation. And the former is more practical and safe, indicating a wide clinical application in the future.

Comparative analysis of the secretory proteome of human adipose stromal vascular fraction cells during adipogenesis

Adipogenesis is a complex process that is accompanied by a number of molecular events. In this study, a proteomic approach was adopted to identify secretory factors associated with adipogenesis. A label-free shotgun proteomic strategy was implemented to analyze proteins secreted by human adipose stromal vascular fraction cells and differentiated adipocytes. A total of 474 proteins were finally identified and classified according to quantitative changes and statistical significances. Briefly, 177 proteins were significantly upregulated during adipogenesis (Class I), whereas 60 proteins were significantly downregulated (Class II). Changes in the expressions of several proteins were confirmed by quantitative RT-PCR and immunoblotting. One obvious finding based on proteomic data was that the amounts of several extracellular modulators of Wnt and transforming growth factor-beta (TGF-beta) signaling changed during adipogenesis. The expressions of secreted frizzled-related proteins, dickkopf-related proteins, and latent TGF-beta-binding proteins were found to be altered during adipogenesis, which suggests that they participate in the fine regulation of Wnt and TGF-beta signaling. This study provides useful tools and important clues regarding the roles of secretory factors during adipogenic differentiation, and provides information related to obesity and obesity-related metabolic diseases.

Obesity-associated mouse adipose stem cell secretion of monocyte chemotactic protein-1

Studies showed that monocyte chemotactic protein-1 (MCP-1) concentrations are increased in obesity. In our current study, we demonstrate that plasma MCP-1 level in leptin-deficient ob/ob mice is significantly higher than in lean mice. Furthermore, we determined that basal adipose tissue MCP-1 mRNA levels are significantly higher in ob/ob mice compared with lean mice. To determine the mechanisms underlying obesity-associated increases in plasma and adipose tissue MCP-1 levels, we determined adipose tissue cell type sources of MCP-1 production. Our data show that adipose tissue stem cells (CD34(+)), macrophages (F4/80(+)), and stromal vascular fraction (SVF) cells express significantly higher levels of MCP-1 compared with adipocytes under both basal and lipopolysaccharide (LPS)-stimulated conditions. Furthermore, basal and LPS-induced MCP-1 secretion levels were the same for both adipose F4/80(+) and CD34(+) cells, whereas adipose CD34(+) cells have twofold higher cell numbers (30% of total SVF cells) compared with F4/80(+) macrophages (15%). Our data also show that CD34(+) cells from visceral adipose tissue depots secrete significantly higher levels of MCP-1 ex vivo when compared with CD34(+) cells from subcutaneous adipose tissue depots. Taken together, our data suggest that adipose CD34(+) stem cells may play an important role in obesity-associated increases in plasma MCP-1 levels.