Adipose-derived Mesenchymal Cells Research Articles

Mitogenic and chondrogenic effects of fibroblast growth factor-2 in adipose-derived mesenchymal cells

Adipose-derived mesenchymal cells (AMCs) have demonstrated a great capacity for differentiating into bone, cartilage, and fat. Studies using bone marrow-derived mesenchymal cells (BMSCs) have shown that fibroblast growth factor (FGF)-2, a potent mitogenic factor, plays an important role in tissue engineering due to its effects in proliferation and differentiation for mesenchymal cells. The aim of this study was to investigate the function of FGF-2 in AMC chondrogenic differentiation and its possible contributions to cell-based therapeutics in skeletal tissue regeneration. Data demonstrated that FGF-2 significantly promoted the proliferation of AMCs and enhanced chondrogenesis in three-dimensional micromass culture. Moreover, priming AMCs with treatment of FGF-2 at 10 ng/ml demonstrated that cells underwent chondrogenic phenotypic differentiation, possibly by inducing N-Cadherin, FGF-receptor 2, and transcription factor Sox9. Our results indicated that FGF-2 potentiates chondrogenesis in AMCs, similar to its functions in BMSCs, suggesting the versatile potential applications of FGF-2 in skeletal regeneration and cartilage repair.

Effect of reduced oxygen tension on chondrogenesis and osteogenesis in adipose-derived mesenchymal cells

Recent studies have demonstrated that adipose-derived mesenchymal cells (AMCs) offer great promise for cell-based therapies because of their ability to differentiate toward bone, cartilage, and fat. Given that cartilage is an avascular tissue and that mesenchymal cells experience hypoxia during prechondrogenic condensation in endochondral ossification, the goal of this study was to understand the influence of oxygen tension on AMC differentiation into bone and cartilage. In vitro chondrogenesis was induced using a three-dimensional micromass culture model supplemented with TGF-beta1. Collagen II production and extracellular matrix proteoglycans were assessed with immunohistochemistry and Alcian blue staining, respectively. Strikingly, micromasses differentiated in reduced oxygen tension (2% O(2)) showed markedly decreased chondrogenesis. Osteogenesis was induced using osteogenic medium supplemented with retinoic acid or vitamin D and was assessed with alkaline phosphatase activity and mineralization. AMCs differentiated in both 21 and 2% O(2) environments. However, osteogenesis was severely diminished in a low-oxygen environment. These data demonstrated that hypoxia strongly inhibits in vitro chondrogenesis and osteogenesis in AMCs.

The Osteogenic Potential of Adipose-Derived Mesenchymal Cells Is Maintained with Aging

Adipose-derived mesenchymal cells are multipotent progenitor cells derived from the vascular-stromal compartment of adipose tissue. Although we have recently shown that these cells, from both juvenile and adult animals, are capable of forming bone in vivo, a detailed examination of the differences in the biology of these two populations (and in particular their ability to form bone) has not been performed. Adipose-derived mesenchymal cells were harvested from juvenile (6-day-old) and adult (60-day-old) mice. Differences in cellular attachment, proliferation, and proliferating cell nuclear antigen production were assessed. The ability of cells to undergo adipogenic differentiation was determined by Oil Red O staining. Early osteogenic differentiation was determined with alkaline phosphatase staining, and terminal differentiation with von Kossa staining as well as determination of extracellular matrix calcium content. All experiments were performed in triplicate. Greater attachment, proliferation, and proliferating cell nuclear antigen production were seen in juvenile as compared with adult adipose-derived mesenchymal cells. The juvenile cells underwent significantly greater adipogenic differentiation than did adult cells (p < 0.001). Interestingly, the adult cells were capable of robust early and terminal osteogenic differentiation, with levels of all three osteo-genic assays being similar to those seen in juvenile cells. Differences were not statistically significant. Although biologic differences exist between adipose-derived mesenchymal cells from juveniles and adults, the osteogenic capacity of these cells appears to be minimally affected by donor age. This suggests that these cells may be a particularly useful cellular resource in the design of cell-based therapies for skeletal regeneration in an aging population.

The effect of pre-exposure to hypoxia on in vitro chondrogenesis of adipose-derived mesenchymal cells (AMCs)

The effect of pre-exposure to hypoxia on in vitro chondrogenesis of adipose-derived mesenchymal cells (AMCs)

Mouse adipose-derived mesenchymal stromal cells undergo osteogenic differentiation in vitro and in vivo

Abstract Introduction: Although the multilineage potential of human processed lipoaspirate has previously been demonstrated, few studies exist utilizing mouse adipose-derived mesenchymal cells (ADMSCs) in vitro or in vivo. Here, we develop a method for osteogenic differentiation of ADMSCs in vitro and utilize them to repair calvarial defects in vivo. Methods: ADMSCs were harvested from 3 week old female FVB mice. ADMSCs were cultured in standard osteogenic media with various concentrations of BMP-2 or retinoic acid (RA) for 3 weeks. Growth and differentiation were assessed via cell counting, Oil Red O (ORO), alkaline phosphatase (AP), and von Kossa (VK) staining. Apatite-coated poly-lactic co-glycolic acid (PLGA) scaffolds were then seeded with ADMSCs and implanted into critical sized (4mm) calvarial defects in adult male mice. Calvarial regeneration was assessed using histology and radiography. Results: Only slight differences in proliferation were seen in response to BMP2, RA, or BMP2 + RA. ORO staining was dramatically decreased in treated cells. AP and von Kossa staining were induced in a synergistic fashion by BMP2 + RA. In vivo experiments revealed successful healing of calvarial defects by 12 weeks after surgery. ADMSC-seeded scaffolds produced significant intramembranous bone formation by 2 weeks, and areas of complete bony bridging by 12 weeks as demonstrated by X-ray and histology. Conclusions: Our data demonstrate successful osteogenic differentiation of ADMSCs in vitro and in vivo. This novel mouse model potentiates further investigation into the mechanisms governing osteogenesis and the epigenetic manipulations that can be used to enhance this process.